Cerebral morphology and dopamine D2/D3receptor distribution in humans: A combined [18F]fallypride and voxel-based morphometry study

PubMed Central

Woodward, Neil D.; Zald, David H.; Ding, Zhaohua; Riccardi, Patrizia; Ansari, M. Sib; Baldwin, Ronald M.; Cowan, Ronald L.; Li, Rui; Kessler, Robert M.

2009-01-01

The relationship between cerebral morphology and the expression of dopamine receptors has not been extensively studied in humans. Elucidation of such relationships may have important methodological implications for clinical studies of dopamine receptor ligand binding differences between control and patient groups. The association between cerebral morphology and dopamine receptor distribution was examined in 45 healthy subjects who completed T1-weighted structural MRI and PET scanning with the D2/D3 ligand [18F]fallypride. Optimized voxel-based morphometry was used to create grey matter volume and density images. Grey matter volume and density images were correlated with binding potential (BPND) images on a voxel-by-voxel basis using the Biological Parametric Mapping toolbox. Associations between cerebral morphology and BPND were also examined for selected regions-of-interest (ROIs) after spatial normalization. Voxel-wise analyses indicated that grey matter volume and density positively correlated with BPND throughout the midbrain, including the substantia nigra. Positive correlations were observed in medial cortical areas, including anterior cingulate and medial prefrontal cortex, and circumscribed regions of the temporal, frontal, and parietal lobes. ROI analyses revealed significant positive correlations between BPND and cerebral morphology in the caudate, thalamus, and amygdala. Few negative correlations between morphology and BPND were observed. Overall, grey matter density appeared more strongly correlated with BPND than grey matter volume. Cerebral morphology, particularly grey matter density, correlates with [18F]fallypride BPND in a regionally specific manner. Clinical studies comparing dopamine receptor availability between clinical and control groups may benefit by accounting for potential differences in cerebral morphology that exist even after spatial normalization. PMID:19457373

Cerebral morphology and dopamine D2/D3 receptor distribution in humans: a combined [18F]fallypride and voxel-based morphometry study.

PubMed

Woodward, Neil D; Zald, David H; Ding, Zhaohua; Riccardi, Patrizia; Ansari, M Sib; Baldwin, Ronald M; Cowan, Ronald L; Li, Rui; Kessler, Robert M

2009-05-15

The relationship between cerebral morphology and the expression of dopamine receptors has not been extensively studied in humans. Elucidation of such relationships may have important methodological implications for clinical studies of dopamine receptor ligand binding differences between control and patient groups. The association between cerebral morphology and dopamine receptor distribution was examined in 45 healthy subjects who completed T1-weighted structural MRI and PET scanning with the D(2)/D(3) ligand [(18)F]fallypride. Optimized voxel-based morphometry was used to create grey matter volume and density images. Grey matter volume and density images were correlated with binding potential (BP(ND)) images on a voxel-by-voxel basis using the Biological Parametric Mapping toolbox. Associations between cerebral morphology and BP(ND) were also examined for selected regions-of-interest (ROIs) after spatial normalization. Voxel-wise analyses indicated that grey matter volume and density positively correlated with BP(ND) throughout the midbrain, including the substantia nigra. Positive correlations were observed in medial cortical areas, including anterior cingulate and medial prefrontal cortex, and circumscribed regions of the temporal, frontal, and parietal lobes. ROI analyses revealed significant positive correlations between BP(ND) and cerebral morphology in the caudate, thalamus, and amygdala. Few negative correlations between morphology and BP(ND) were observed. Overall, grey matter density appeared more strongly correlated with BP(ND) than grey matter volume. Cerebral morphology, particularly grey matter density, correlates with [(18)F]fallypride BP(ND) in a regionally specific manner. Clinical studies comparing dopamine receptor availability between clinical and control groups may benefit by accounting for potential differences in cerebral morphology that exist even after spatial normalization.

Improved performance by morphology control via fullerenes in PBDT-TBT-alkoBT based organic solar cells

DOE PAGES

Khatiwada, Devendra; Venkatesan, Swaminathan; Chen, QIliang; ...

2015-07-03

In this work, we report improved performance by controlling morphology using different fullerene derivatives in poly{2-octyldodecyloxy-benzo[1,2-b;3,4-b]dithiophene-alt-5,6-bis(dodecyloxy)-4,7- di(thieno[3,2-b]thiophen-2-yl)-benzo[c][1,2,5]thiadiazole} (PBDT-TBT-alkoBT) based organic solar cells. PC60BM and PC70BM fullerenes were used to investigate the characteristic change in morphology and device performance. Fullerene affects device efficiency by changing active layer morphology. PC70BM with broader absorption than PC 60BM resulted in reduced device performance which was elucidated by the intermixed granular morphology separating each larger grain in the PC70BM/polymer composite layer which created higher density of traps. However after adding additive 1,8-diiodooctane (DIO), the fibrous morphology was observed due to reduced solubility of polymer andmore » increased solubility of PC 70BM in chloroform. The fibrous morphology improved charge transport leading to increase in overall device performance. Atomic force microscopies (AFM), photo induced charge extraction by linearly increasing voltage (photo-CELIV), and Kelvin prove force microscope (KPFM) were used to investigate nanoscale morphology of active layer with different fullerene derivatives. For PC 60BM based active layer, AFM images revealed dense fibrous morphology and more distinct fibrous morphology was observed by adding DIO. The PC 70BM based active layer only exhibited intermixed granular morphology instead of fibrous morphology observed in PC60BM based active layer. However, addition of DIO in PC 70BM based active layer led to fibrous morphology. When additive DIO was not used, a wider distribution of surface potential was observed for PC 70BM than PC 60BM based active layer by KPFM measurements, indicating 2 polymer and fullerene domains are separated. When DIO was used, narrower distribution of surface potential for both PC 70BM and PC 60BM based active layers was observed. Photo-CELIV experiment showed larger extracted charge carrier density and mobility in PC 70BM/DIO film.« less

Improved performance by morphology control via fullerenes in PBDT-TBT-alkoBT based organic solar cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khatiwada, Devendra; Venkatesan, Swaminathan; Chen, QIliang

In this work, we report improved performance by controlling morphology using different fullerene derivatives in poly{2-octyldodecyloxy-benzo[1,2-b;3,4-b]dithiophene-alt-5,6-bis(dodecyloxy)-4,7- di(thieno[3,2-b]thiophen-2-yl)-benzo[c][1,2,5]thiadiazole} (PBDT-TBT-alkoBT) based organic solar cells. PC60BM and PC70BM fullerenes were used to investigate the characteristic change in morphology and device performance. Fullerene affects device efficiency by changing active layer morphology. PC70BM with broader absorption than PC 60BM resulted in reduced device performance which was elucidated by the intermixed granular morphology separating each larger grain in the PC70BM/polymer composite layer which created higher density of traps. However after adding additive 1,8-diiodooctane (DIO), the fibrous morphology was observed due to reduced solubility of polymer andmore » increased solubility of PC 70BM in chloroform. The fibrous morphology improved charge transport leading to increase in overall device performance. Atomic force microscopies (AFM), photo induced charge extraction by linearly increasing voltage (photo-CELIV), and Kelvin prove force microscope (KPFM) were used to investigate nanoscale morphology of active layer with different fullerene derivatives. For PC 60BM based active layer, AFM images revealed dense fibrous morphology and more distinct fibrous morphology was observed by adding DIO. The PC 70BM based active layer only exhibited intermixed granular morphology instead of fibrous morphology observed in PC60BM based active layer. However, addition of DIO in PC 70BM based active layer led to fibrous morphology. When additive DIO was not used, a wider distribution of surface potential was observed for PC 70BM than PC 60BM based active layer by KPFM measurements, indicating 2 polymer and fullerene domains are separated. When DIO was used, narrower distribution of surface potential for both PC 70BM and PC 60BM based active layers was observed. Photo-CELIV experiment showed larger extracted charge carrier density and mobility in PC 70BM/DIO film.« less

The Morphologies of the Semiconductor Oxides and Their Gas-Sensing Properties

PubMed Central

Lv, Xin; Li, Shuang; Wang, Qingji

2017-01-01

Semiconductor oxide chemoresistive gas sensors are widely used for detecting deleterious gases due to low cost, simple preparation, rapid response and high sensitivity. The performance of gas sensor is greatly affected by the morphology of the semiconductor oxide. There are many semiconductor oxide morphologies, including zero-dimensional, one-dimensional, two-dimensional and three-dimensional ones. The semiconductor oxides with different morphologies significantly enhance the gas-sensing performance. Among the various morphologies, hollow nanostructures and core-shell nanostructures are always the focus of research in the field of gas sensors due to their distinctive structural characteristics and superior performance. Herein the morphologies of semiconductor oxides and their gas-sensing properties are reviewed. This review also proposes a potential strategy for the enhancement of gas-sensing performance in the future. PMID:29189714

The Potential of Computational Fluid Dynamics Simulation on Serial Monitoring of Hemodynamic Change in Type B Aortic Dissection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Simon C. H., E-mail: simonyu@cuhk.edu.hk; Liu, Wen; Wong, Randolph H. L.

PurposeWe aimed to assess the potential of computational fluid dynamics simulation (CFD) in detecting changes in pressure and flow velocity in response to morphological changes in type B aortic dissection.Materials and MethodsPressure and velocity in four morphological models of type B aortic dissection before and after closure of the entry tear were calculated with CFD and analyzed for changes among the different scenarios. The control model (Model 1) was patient specific and built from the DICOM data of CTA, which bore one entry tear and three re-entry tears. Models 2–4 were modifications of Model 1, with two re-entry tears lessmore » in Model 2, one re-entry tear more in Model 3, and a larger entry tear in Model 4.ResultsThe pressure and velocity pertaining to each of the morphological models were unique. Changes in pressure and velocity findings were accountable by the changes in morphological features of the different models. There was no blood flow in the false lumen across the entry tear after its closure, the blood flow direction across the re-entry tears was reversed after closure of the entry tear.ConclusionCFD simulation is probably useful to detect hemodynamic changes in the true and false lumens of type B aortic dissection in response to morphological changes, it may potentially be developed into a non-invasive and patient-specific tool for serial monitoring of hemodynamic changes of type B aortic dissection before and after treatment.« less

Global Diversity of the Placozoa

PubMed Central

Eitel, Michael; Osigus, Hans-Jürgen; DeSalle, Rob; Schierwater, Bernd

2013-01-01

The enigmatic animal phylum Placozoa holds a key position in the metazoan Tree of Life. A simple bauplan makes it appear to be the most basal metazoan known and genetic evidence also points to a position close to the last common metazoan ancestor. Trichoplax adhaerens is the only formally described species in the phylum to date, making the Placozoa the only monotypic phylum in the animal kingdom. However, recent molecular genetic as well as morphological studies have identified a high level of diversity, and hence a potential high level of taxonomic diversity, within this phylum. Different taxa, possibly at different taxonomic levels, are awaiting description. In this review we firstly summarize knowledge on the morphology, phylogenetic position and ecology of the Placozoa. Secondly, we give an overview of placozoan morphological and genetic diversity and finally present an updated distribution of placozoan populations. We conclude that there is great potential and need to erect new taxa and to establish a firm system for this taxonomic tabula rasa. PMID:23565136

Brain Potentials for Derivational Morphology: An ERP Study of Deadjectival Nominalizations in Spanish

ERIC Educational Resources Information Center

Havas, Viktoria; Rodriguez-Fornells, Antoni; Clahsen, Harald

2012-01-01

This study investigates brain potentials to derived word forms in Spanish. Two experiments were performed on derived nominals that differ in terms of their productivity and semantic properties but are otherwise similar, an acceptability judgment task and a reading experiment using event-related brain potentials (ERPs) in which correctly and…

The Epoch of Disk Formation: z is Approximately l to Today

NASA Technical Reports Server (NTRS)

Kassin, Susan; Gardner, Jonathan; Weiner, Ben; Faber, Sandra

2012-01-01

We present data on galaxy kinematics, morphologies, and star-formation rates over 0.1 less than z less than 1.2 for approximately 500 blue galaxies. These data show how systems like our own Milky-Way have come into being. At redshifts around 1, about half the age of the Universe ago, Milky-Way mass galaxies were different beasts than today. They had a significant amount of disturbed motions, disturbed morphologies, shallower potential wells, higher specific star-formation rates, and likely higher gas fractions. Since redshift approximately 1, galaxies have decreased in disturbed motions, increased in rotation velocity and potential well depth, become more well-ordered morphologically, and decreased in specific star-formation rate. We find interrelationships between these measurements. Galaxy kinematics are correlated with morphology and specific star-formation rate such that galaxies with the fastest rotation velocities and the least amounts of disturbed motions have the most well-ordered morphologies and the lowest specific star-formation rates. The converse is true. Moreover, we find that the rate at which galaxies become more well-ordered kinematically (i.e., increased rotation velocity, decreased disturbed motions) and morphologically is directly proportional to their stellar mass.

What can morphology tell us about ecology of four invasive goby species?

PubMed

Jakubčinová, K; Simonović, P; Števove, B; Čanak Atlagić, J; Kováč, V

2017-05-01

This study presents a detailed comparative analysis of external morphology of four of the most invasive goby species in Europe (round goby Neogobius melanostomus, bighead goby Ponticola kessleri, monkey goby Neogobius fluviatilis and racer goby Ponticola gymnotrachelus) and interprets some ecological requirements of these species based on their morphological attributes. The results are evaluated within an ontogenetic context, and the morphological differences between the species are discussed in terms of the question: can special external shape adaptations help to assess the invasive potential of each species? The morphometric analyses demonstrate important differences between the four invasive gobies. Neogobius melanostomus appears to have the least specialized external morphology that may favour its invasive success: little specialization to habitat or diet means reduced restraints on overall ecological requirements. The other three species were found to possess some morphological specializations (P. kessleri to large prey, N. fluviatilis to sandy habitats and P. gymnotrachelus to macrophytes), but none of these gobies have managed to colonize such large areas or to reach such overall abundances as N. melanostomus. © 2017 The Fisheries Society of the British Isles.

Whole-genome sequencing in a pair of monozygotic twins with discordant cleft lip and palate subtypes.

PubMed

Takahashi, Masahiro; Hosomichi, Kazuyoshi; Yamaguchi, Tetsutaro; Nagahama, Ryo; Yoshida, Hiroshi; Maki, Koutaro; Marazita, Mary L; Weinberg, Seth M; Tajima, Atsushi

2018-06-06

Orofacial clefts (OFCs) are common and aetiologically complex birth defects. This study explored potential genetic differences in a pair of Japanese monozygotic (MZ) twins with different forms of OFC using whole-genome sequencing. One co-twin (MZ-1) presented with non-syndromic bilateral cleft lip and palate; the other co-twin (MZ-2) had non-syndromic bilateral cleft lip and unilateral left-sided cleft alveolus. Neither parent had an OFC. Craniofacial morphologic features and potential genetic differences were compared using standard cephalometry and whole-genome sequencing, respectively. Morphologically, MZ-1 had a smaller vertical mandibular height, compared to MZ-2. However, no discordant genetic differences were detected. Moreover, both twins and their parents harboured rare candidate gene variants (GRHL3; TPM1) considered to be associated with OFCs. The observed differences between MZ-1 and MZ-2 in craniofacial morphology assessed by cephalograms might be directly attributable to the effects of the OFC on growth and/or differences in surgical history, given the lack of any differences in genetic background. However, comparisons of discordant MZ twins should continue to identify novel candidates that might control OFC or that might partly explain the missing heritability for this common birth defect, in addition to understanding craniofacial growth and development. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Effects of electrode distance and nature of electrolyte on the diameter of titanium dioxide nanotube

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abbasi, S., E-mail: sum.abbasi@gmail.com; Mohamed, N. M., E-mail: noranimuti-mohamed@petronas.com.my; Singh, B. S. M., E-mail: balbir@petronas.com.my

2015-07-22

The titanium nanotubes were synthesized using viscous electrolytes consisting of ethylene glycol and non-viscous electrolytes consisting of aqueous solution of hydrofluoric acid. Sodium fluoride and ammonium fluoride were utilized as the source of fluorine ions. The samples were then characterized by field emission scanning electron microscope (FE-SEM). Their morphologies were investigated under different anodic potentials and various electrolyte compositions. It was found out that nanotubes can be obtained in fluoride ions and morphology is dependent on various parameters like anodic potential, time, electrolyte composition and the effects by varying the distance between the electrodes on the morphology was also investigated.more » It was found that by altering the distance between the electrodes, change in the diameter and the porosity was observed.« less

Cryptic or pseudocryptic: can morphological methods inform copepod taxonomy? An analysis of publications and a case study of the Eurytemora affinis species complex

PubMed Central

Lajus, Dmitry; Sukhikh, Natalia; Alekseev, Victor

2015-01-01

Interest in cryptic species has increased significantly with current progress in genetic methods. The large number of cryptic species suggests that the resolution of traditional morphological techniques may be insufficient for taxonomical research. However, some species now considered to be cryptic may, in fact, be designated pseudocryptic after close morphological examination. Thus the “cryptic or pseudocryptic” dilemma speaks to the resolution of morphological analysis and its utility for identifying species. We address this dilemma first by systematically reviewing data published from 1980 to 2013 on cryptic species of Copepoda and then by performing an in-depth morphological study of the former Eurytemora affinis complex of cryptic species. Analyzing the published data showed that, in 5 of 24 revisions eligible for systematic review, cryptic species assignment was based solely on the genetic variation of forms without detailed morphological analysis to confirm the assignment. Therefore, some newly described cryptic species might be designated pseudocryptic under more detailed morphological analysis as happened with Eurytemora affinis complex. Recent genetic analyses of the complex found high levels of heterogeneity without morphological differences; it is argued to be cryptic. However, next detailed morphological analyses allowed to describe a number of valid species. Our study, using deep statistical analyses usually not applied for new species describing, of this species complex confirmed considerable differences between former cryptic species. In particular, fluctuating asymmetry (FA), the random variation of left and right structures, was significantly different between forms and provided independent information about their status. Our work showed that multivariate statistical approaches, such as principal component analysis, can be powerful techniques for the morphological discrimination of cryptic taxons. Despite increasing cryptic species designations, morphological techniques have great potential in determining copepod taxonomy. PMID:26120427

Non-invasive metabolomic profiling of embryo culture media and morphology grading to predict implantation outcome in frozen-thawed embryo transfer cycles.

PubMed

Li, Xiong; Xu, Yan; Fu, Jing; Zhang, Wen-Bi; Liu, Su-Ying; Sun, Xiao-Xi

2015-11-01

Assessment of embryo viability is a crucial component of in vitro fertilization and currently relies largely on embryo morphology and cleavage rate. Because morphological assessment remains highly subjective, it can be unreliable in predicting embryo viability. This study investigated the metabolomic profiling of embryo culture media using near-infrared (NIR) spectroscopy for predicting the implantation potential of human embryos in frozen-thawed embryo transfer (FET) cycles. Spent embryo culture media was collected on day 4 after thawed embryo transfer (n = 621) and analysed using NIR spectroscopy. Viability scores were calculated using a predictive multivariate algorithm of fresh embryos with known pregnancy outcomes. The mean viability indices of embryos resulting in clinical pregnancy following FET were significantly higher than those of non-implanted embryos and differed between the 0, 50, and 100 % implantation groups. Notably, the 0 % group index was significantly lower than the 100 % implantation group index (-0.787 ± 0.382 vs. 1.064 ± 0.331, P < 0.01). To predict implantation outcomes, we examined the area under the ROC curve (AUCROC), which was significantly higher for the viability than for the morphology score (0.94 vs. 0.55; P < 0.01); however, the AUCROCs for the composite and viability scores did not differ significantly (0.92 vs. 0.94; P > 0.05). NIR metabolomic profiling of thawed embryo culture media is independent of morphology and correlates with embryo implantation potential in FET cycles. The viability score alone or in conjunction with morphologic grading is a more objective marker for implantation outcome in FET cycles than morphology alone.

Concentration gradient induced morphology evolution of silica nanostructure growth on photoresist-derived carbon micropatterns

NASA Astrophysics Data System (ADS)

Liu, Dan; Shi, Tielin; Xi, Shuang; Lai, Wuxing; Liu, Shiyuan; Li, Xiaoping; Tang, Zirong

2012-09-01

The evolution of silica nanostructure morphology induced by local Si vapor source concentration gradient has been investigated by a smart design of experiments. Silica nanostructure or their assemblies with different morphologies are obtained on photoresist-derived three-dimensional carbon microelectrode array. At a temperature of 1,000°C, rope-, feather-, and octopus-like nanowire assemblies can be obtained along with the Si vapor source concentration gradient flow. While at 950°C, stringlike assemblies, bamboo-like nanostructures with large joints, and hollow structures with smaller sizes can be obtained along with the Si vapor source concentration gradient flow. Both vapor-liquid-solid and vapor-quasiliquid-solid growth mechanisms have been applied to explain the diverse morphologies involving branching, connecting, and batch growth behaviors. The present approach offers a potential method for precise design and controlled synthesis of nanostructures with different features.

Effect of bath temperature on structure, morphology and thermoelectric properties of CoSb{sub 3} thin films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yadav, Suchitra, E-mail: suchitrayadav87@gmail.com; Pandya, Dinesh K.; Chaudhary, Sujeet

2016-05-23

CoSb{sub 3} thin films are deposited on conducting glass substrates (FTO) by electrodeposition at different bath temperatures (60°C, 70°C and 80°C) and the resulting influence of the bath temperature on the structure, morphology and electrical properties of films is investigated. X-ray diffraction confirms the formation of CoSb{sub 3} phase in the films. Scanning electron microscopy reveals that different morphologies ranging from branched nano-flakes to nano-needles evolve as bath temperature increases. It is concluded that a growth temperature of 80°C is suitable for producing CoSb{sub 3} films with such properties that show potential feasibility for thermoelectric applications.

Simultaneous formation of multiscale hierarchical surface morphologies through sequential wrinkling and folding

NASA Astrophysics Data System (ADS)

Wang, Yu; Sun, Qingyang; Xiao, Jianliang

2018-02-01

Highly organized hierarchical surface morphologies possess various intriguing properties that could find important potential applications. In this paper, we demonstrate a facile approach to simultaneously form multiscale hierarchical surface morphologies through sequential wrinkling. This method combines surface wrinkling induced by thermal expansion and mechanical strain on a three-layer structure composed of an aluminum film, a hard Polydimethylsiloxane (PDMS) film, and a soft PDMS substrate. Deposition of the aluminum film on hard PDMS induces biaxial wrinkling due to thermal expansion mismatch, and recovering the prestrain in the soft PDMS substrate leads to wrinkling of the hard PDMS film. In total, three orders of wrinkling patterns form in this process, with wavelength and amplitude spanning 3 orders of magnitude in length scale. By increasing the prestrain in the soft PDMS substrate, a hierarchical wrinkling-folding structure was also obtained. This approach can be easily extended to other thin films for fabrication of multiscale hierarchical surface morphologies with potential applications in different areas.

Morphological processing in a second language: behavioral and event-related brain potential evidence for storage and decomposition.

PubMed

Hahne, Anja; Mueller, Jutta L; Clahsen, Harald

2006-01-01

This study reports the results of two behavioral and two event-related brain potential experiments examining the processing of inflected words in second-language (L2) learners with Russian as their native language. Two different subsystems of German inflection were studied, participial inflection and noun plurals. For participial forms, L2 learners were found to widely generalize the -t suffixation rule in a nonce-word elicitation task, and in the event-related brain potential experiment, they showed an anterior negativity followed by a P600-both results resembling previous findings from native speakers of German on the same materials. For plural formation, the L2 learners displayed different preference patterns for regular and irregular forms in an off-line plural judgment task. Regular and irregular plural forms also differed clearly with regard to their brain responses. Whereas overapplications of the -s plural rule produced a P600 component, overapplications of irregular patterns elicited an N400. In contrast to native speakers of German, however, the L2 learners did not show an anterior negativity for -s plural overapplications. Taken together, the results show clear dissociations between regular and irregular inflection for both morphological subsystems. We argue that the two processing routes posited by dual-mechanism models of inflection (lexical storage and morphological decomposition) are also employed by L2 learners.

Headless spermatozoa in infertile men.

PubMed

Sha, Y-W; Ding, L; Wu, J-X; Lin, S-B; Wang, X; Ji, Z-Y; Li, P

2017-10-01

Spermatozoa morphology, an important parameter in a semen specimen's potential fertility evaluation, is a significant factor for in vitro fertilisation in assisted reproductive technology. Eleven sterile men with headless spermatozoa, a type of human teratozoospermia, are presented. Their ejaculates' headless spermatozoa percentages were high with rare normal spermatozoa forms. Additionally, abnormal morphology (e.g. round-headed or microcephalic spermatozoa) was also found. Spermatozoa motility was somewhat affected, potentially because of the missing mitochondrial sheath at the sperm tail base. Patients who underwent assisted reproductive technology treatment experienced adverse pregnancy outcomes. Work types and corresponding environments seemed irrelevant, but specific family history may have prompted its genetic origin. Computer-assisted semen analysis systems easily mistake headless spermatozoa as oligozoospermia because of nonrecognition of the loose head. However, morphological testing, especially with an electronic microscope, clearly identifies abnormal spermatozoa. Future exploration requires more methods investigating the frequency and percentage of this morphological abnormality in different populations with varied fertility levels. Such research would estimate the probable correlation of the abnormality with other semen parameters and examine the potential developmental or genetic origins. During clinical work, medical staff should detect these cases, avoid misdiagnosis and provide proper consultation about diagnosis and assisted reproductive technology treatment. © 2016 Blackwell Verlag GmbH.

Contrasting light spectra constrain the macro and microstructures of scleractinian corals.

PubMed

Rocha, Rui J M; Silva, Ana M B; Fernandes, M Helena Vaz; Cruz, Igor C S; Rosa, Rui; Calado, Ricardo

2014-01-01

The morphological plasticity of scleractinian corals can be influenced by numerous factors in their natural environment. However, it is difficult to identify in situ the relative influence of a single biotic or abiotic factor, due to potential interactions between them. Light is considered as a major factor affecting coral skeleton morphology, due to their symbiotic relation with photosynthetic zooxanthellae. Nonetheless, most studies addressing the importance of light on coral morphological plasticity have focused on photosynthetically active radiation (PAR) intensity, with the effect of light spectra remaining largely unknown. The present study evaluated how different light spectra affect the skeleton macro- and microstructures in two coral species (Acropora formosa sensu Veron (2000) and Stylophora pistillata) maintained under controlled laboratory conditions. We tested the effect of three light treatments with the same PAR but with a distinct spectral emission: 1) T5 fluorescent lamps with blue emission; 2) Light Emitting Diodes (LED) with predominantly blue emission; and 3) Light Emitting Plasma (LEP) with full spectra emission. To exclude potential bias generated by genetic variability, the experiment was performed with clonal fragments for both species. After 6 months of experiment, it was possible to detect in coral fragments of both species exposed to different light spectra significant differences in morphometry (e.g., distance among corallites, corallite diameter, and theca thickness), as well as in the organization of their skeleton microstructure. The variability found in the skeleton macro- and microstructures of clonal organisms points to the potential pitfalls associated with the exclusive use of morphometry on coral taxonomy. Moreover, the identification of a single factor influencing the morphology of coral skeletons is relevant for coral aquaculture and can allow the optimization of reef restoration efforts.

Translational aspects of rectal evoked potentials: a comparative study in rats and humans

PubMed Central

Nissen, Thomas Dahl; Graversen, Carina; Coen, Steven J.; Hultin, Leif; Aziz, Qasim; Lykkesfeldt, Jens; Drewes, Asbjørn Mohr

2013-01-01

Inconsistencies between species has stunted the progress of developing new analgesics. To increase the success of translating results between species, improved comparable models are required. Twelve rats received rectal balloon distensions on 2 different days separated by 24.3 (SD 24.6) days. Rectal balloon distensions were also performed in 18 humans (mean age: 34 yr; range: 21–56 yr; 12 men) on two separate occasions, separated by 9.3 (SD 5.5) days. In rats, cerebral evoked potentials (CEPs) were recorded by use of implanted skull-electrodes to distension pressure of 80 mmHg. In humans surface electrodes and individualized pressure, corresponding to pain detection threshold, were used. Comparison of morphology was assessed by wavelet analysis. Within- and between-day reproducibility was assessed in terms of latencies, amplitudes, and frequency content. In rats CEPs showed triphasic morphology. No differences in latencies, amplitudes, and power distribution were seen within or between days (all P ≥ 0.5). Peak-to-peak amplitude between the first positive and negative potential were the most reproducible characteristic within and between days (evaluated by intraclass correlation coefficients, ICC) (ICC = 0.99 and ICC = 9.98, respectively). In humans CEPs showed a triphasic morphology. No differences in latencies, amplitudes, or power distribution were seen within or between days (all P ≥ 0.2). Latency to the second negative potential (ICC = 0.98) and the second positive potential (ICC = 0.95) was the most reproducible characteristic within and between days. A unique and reliable translational platform was established assessing visceral sensitivity in rats and humans, which may improve the translational process of developing new drugs targeting visceral pain. PMID:23703652

Associations between sperm abnormalities, breed, age, and scrotal circumference in beef bulls

PubMed Central

Menon, Ajitkumar G.; Barkema, Herman W.; Wilde, Randy; Kastelic, John P.; Thundathil, Jacob C.

2011-01-01

The objectives of this study were to determine the associations of breed, age, and scrotal circumference (SC), and their interaction, on the prevalence of sperm abnormalities in beef bulls in Alberta, Canada, and the percentage of satisfactory potential breeders identified during breeding soundness examination solely due to normal sperm morphology. Eosin-nigrosin stained semen smears and evaluation reports of 1642 bull breeding soundness evaluations were procured from 6 veterinary clinics in Alberta. Sperm morphology was determined for at least 100 sperm per bull. The most common defects were detached head [4.86% ± 5.71%; mean ± standard deviation (s)], distal midpiece reflex (6.19% ± 9.13%), and bent tail (1.01% ± 1.54%). Although breed, age, and SC did not significantly affect the prevalence of head or midpiece defects, morphologically normal or abnormal sperm, tail defects were more prevalent in Angus and Hereford bulls compared with other breeds. Overall, solely on the basis of sperm morphology, 1363 (83.0%) bulls were classified as satisfactory potential breeders and the remainder 279 (17.0%) as unsatisfactory (> 30% abnormal sperm, > 20% defective heads, or both). Although not significantly different, the breed with the highest percentage of satisfactory potential breeders was Limousin (90.6%) and the lowest was Hereford (78.8%). That 17% of bulls subjected to breeding soundness evaluation were designated as unsatisfactory solely on the basis of sperm morphology highlights its importance. PMID:22468020

Fast Census of Moth Diversity in the Neotropics: A Comparison of Field-Assigned Morphospecies and DNA Barcoding in Tiger Moths

PubMed Central

Zenker, Mauricio M.; Rougerie, Rodolphe; Teston, José A.; Laguerre, Michel; Pie, Marcio R.; Freitas, André V. L.

2016-01-01

The morphological species delimitations (i.e. morphospecies) have long been the best way to avoid the taxonomic impediment and compare insect taxa biodiversity in highly diverse tropical and subtropical regions. The development of DNA barcoding, however, has shown great potential to replace (or at least complement) the morphospecies approach, with the advantage of relying on automated methods implemented in computer programs or even online rather than in often subjective morphological features. We sampled moths extensively for two years using light traps in a patch of the highly endangered Atlantic Forest of Brazil to produce a nearly complete census of arctiines (Noctuoidea: Erebidae), whose species richness was compared using different morphological and molecular approaches (DNA barcoding). A total of 1,075 barcode sequences of 286 morphospecies were analyzed. Based on the clustering method Barcode Index Number (BIN) we found a taxonomic bias of approximately 30% in our initial morphological assessment. However, a morphological reassessment revealed that the correspondence between morphospecies and molecular operational taxonomic units (MOTUs) can be up to 94% if differences in genitalia morphology are evaluated in individuals of different MOTUs originated from the same morphospecies (putative cases of cryptic species), and by recording if individuals of different genders in different morphospecies merge together in the same MOTU (putative cases of sexual dimorphism). The results of two other clustering methods (i.e. Automatic Barcode Gap Discovery and 2% threshold) were very similar to those of the BIN approach. Using empirical data we have shown that DNA barcoding performed substantially better than the morphospecies approach, based on superficial morphology, to delimit species of a highly diverse moth taxon, and thus should be used in species inventories. PMID:26859488

Fast Census of Moth Diversity in the Neotropics: A Comparison of Field-Assigned Morphospecies and DNA Barcoding in Tiger Moths.

PubMed

Zenker, Mauricio M; Rougerie, Rodolphe; Teston, José A; Laguerre, Michel; Pie, Marcio R; Freitas, André V L

2016-01-01

The morphological species delimitations (i.e. morphospecies) have long been the best way to avoid the taxonomic impediment and compare insect taxa biodiversity in highly diverse tropical and subtropical regions. The development of DNA barcoding, however, has shown great potential to replace (or at least complement) the morphospecies approach, with the advantage of relying on automated methods implemented in computer programs or even online rather than in often subjective morphological features. We sampled moths extensively for two years using light traps in a patch of the highly endangered Atlantic Forest of Brazil to produce a nearly complete census of arctiines (Noctuoidea: Erebidae), whose species richness was compared using different morphological and molecular approaches (DNA barcoding). A total of 1,075 barcode sequences of 286 morphospecies were analyzed. Based on the clustering method Barcode Index Number (BIN) we found a taxonomic bias of approximately 30% in our initial morphological assessment. However, a morphological reassessment revealed that the correspondence between morphospecies and molecular operational taxonomic units (MOTUs) can be up to 94% if differences in genitalia morphology are evaluated in individuals of different MOTUs originated from the same morphospecies (putative cases of cryptic species), and by recording if individuals of different genders in different morphospecies merge together in the same MOTU (putative cases of sexual dimorphism). The results of two other clustering methods (i.e. Automatic Barcode Gap Discovery and 2% threshold) were very similar to those of the BIN approach. Using empirical data we have shown that DNA barcoding performed substantially better than the morphospecies approach, based on superficial morphology, to delimit species of a highly diverse moth taxon, and thus should be used in species inventories.

Exploring the nature of ecological specialization in a coral reef fish community: morphology, diet and foraging microhabitat use

PubMed Central

Brandl, Simon J.; Robbins, William D.; Bellwood, David R.

2015-01-01

Patterns of ecological specialization offer invaluable information about ecosystems. Yet, specialization is rarely quantified across several ecological niche axes and variables beyond the link between morphological and dietary specialization have received little attention. Here, we provide a quantitative evaluation of ecological specialization in a coral reef fish assemblage (f. Acanthuridae) along one fundamental and two realized niche axes. Specifically, we examined ecological specialization in 10 surgeonfish species with regards to morphology and two realized niche axes associated with diet and foraging microhabitat utilization using a recently developed multidimensional framework. We then investigated the potential relationships between morphological and behavioural specialization. These relationships differed markedly from the traditional ecomorphological paradigm. While morphological specialization showed no relationship with dietary specialization, it exhibited a strong relationship with foraging microhabitat specialization. However, this relationship was inverted: species with specialized morphologies were microhabitat generalists, whereas generalized morphotypes were microhabitat specialists. Interestingly, this mirrors relationships found in plant–pollinator communities and may also be applicable to other ecosystems, highlighting the potential importance of including niche axes beyond dietary specialization into ecomorphological frameworks. On coral reefs, it appears that morphotypes commonly perceived as most generalized may, in fact, be specialized in exploiting flat and easily accessible microhabitats. PMID:26354935

Locomotor activity influences muscle architecture and bone growth but not muscle attachment site morphology.

PubMed

Rabey, Karyne N; Green, David J; Taylor, Andrea B; Begun, David R; Richmond, Brian G; McFarlin, Shannon C

2015-01-01

The ability to make behavioural inferences from skeletal remains is critical to understanding the lifestyles and activities of past human populations and extinct animals. Muscle attachment site (enthesis) morphology has long been assumed to reflect muscle strength and activity during life, but little experimental evidence exists to directly link activity patterns with muscle development and the morphology of their attachments to the skeleton. We used a mouse model to experimentally test how the level and type of activity influences forelimb muscle architecture of spinodeltoideus, acromiodeltoideus, and superficial pectoralis, bone growth rate and gross morphology of their insertion sites. Over an 11-week period, we collected data on activity levels in one control group and two experimental activity groups (running, climbing) of female wild-type mice. Our results show that both activity type and level increased bone growth rates influenced muscle architecture, including differences in potential muscular excursion (fibre length) and potential force production (physiological cross-sectional area). However, despite significant influences on muscle architecture and bone development, activity had no observable effect on enthesis morphology. These results suggest that the gross morphology of entheses is less reliable than internal bone structure for making inferences about an individual's past behaviour. Copyright © 2014 Elsevier Ltd. All rights reserved.

Locomotor activity influences muscle architecture and bone growth but not muscle attachment site morphology

PubMed Central

Rabey, Karyne N.; Green, David J.; Taylor, Andrea B.; Begun, David R.; Richmond, Brian G.; McFarlin, Shannon C.

2014-01-01

The ability to make behavioural inferences from skeletal remains is critical to understanding the lifestyles and activities of past human populations and extinct animals. Muscle attachment site (enthesis) morphology has long been assumed to reflect muscle strength and activity during life, but little experimental evidence exists to directly link activity patterns with muscle development and the morphology of their attachments to the skeleton. We used a mouse model to experimentally test how the level and type of activity influences forelimb muscle architecture of spinodeltoideus, acromiodeltoideus, and superficial pectoralis, bone growth rate and gross morphology of their insertion sites. Over an 11-week period, we collected data on activity levels in one control group and two experimental activity groups (running, climbing) of female wild-type mice. Our results show that both activity type and level increased bone growth rates influenced muscle architecture, including differences in potential muscular excursion (fibre length) and potential force production (physiological cross-sectional area). However, despite significant influences on muscle architecture and bone development, activity had no observable effect on enthesis morphology. These results suggest that the gross morphology of entheses is less reliable than internal bone structure for making inferences about an individual’s past behaviour. PMID:25467113

Exploring the nature of ecological specialization in a coral reef fish community: morphology, diet and foraging microhabitat use.

PubMed

Brandl, Simon J; Robbins, William D; Bellwood, David R

2015-09-22

Patterns of ecological specialization offer invaluable information about ecosystems. Yet, specialization is rarely quantified across several ecological niche axes and variables beyond the link between morphological and dietary specialization have received little attention. Here, we provide a quantitative evaluation of ecological specialization in a coral reef fish assemblage (f. Acanthuridae) along one fundamental and two realized niche axes. Specifically, we examined ecological specialization in 10 surgeonfish species with regards to morphology and two realized niche axes associated with diet and foraging microhabitat utilization using a recently developed multidimensional framework. We then investigated the potential relationships between morphological and behavioural specialization. These relationships differed markedly from the traditional ecomorphological paradigm. While morphological specialization showed no relationship with dietary specialization, it exhibited a strong relationship with foraging microhabitat specialization. However, this relationship was inverted: species with specialized morphologies were microhabitat generalists, whereas generalized morphotypes were microhabitat specialists. Interestingly, this mirrors relationships found in plant-pollinator communities and may also be applicable to other ecosystems, highlighting the potential importance of including niche axes beyond dietary specialization into ecomorphological frameworks. On coral reefs, it appears that morphotypes commonly perceived as most generalized may, in fact, be specialized in exploiting flat and easily accessible microhabitats. © 2015 The Author(s).

Growth of elaborate microbial pinnacles in Lake Vanda, Antarctica.

PubMed

Sumner, D Y; Jungblut, A D; Hawes, I; Andersen, D T; Mackey, T J; Wall, K

2016-11-01

Microbial pinnacles in ice-covered Lake Vanda, McMurdo Dry Valleys, Antarctica, extend from the base of the ice to more than 50 m water depth. The distribution of microbial communities, their photosynthetic potential, and pinnacle morphology affects the local accumulation of biomass, which in turn shapes pinnacle morphology. This feedback, plus environmental stability, promotes the growth of elaborate microbial structures. In Lake Vanda, all mats sampled from greater than 10 m water depth contained pinnacles with a gradation in size from <1-mm-tall tufts to pinnacles that were centimeters tall. Small pinnacles were cuspate, whereas larger ones had variable morphology. The largest pinnacles were up to ~30 cm tall and had cylindrical bases and cuspate tops. Pinnacle biomass was dominated by cyanobacteria from the morphological and genomic groups Leptolyngbya, Phormidium, and Tychonema. The photosynthetic potential of these cyanobacterial communities was high to depths of several millimeters into the mat based on PAM fluorometry, and sufficient light for photosynthesis penetrated ~5 mm into pinnacles. The distribution of photosynthetic potential and its correlation to pinnacle morphology suggests a working model for pinnacle growth. First, small tufts initiate from random irregularities in prostrate mat. Some tufts grow into pinnacles over the course of ~3 years. As pinnacles increase in size and age, their interiors become colonized by a more diverse community of cyanobacteria with high photosynthetic potential. Biomass accumulation within this subsurface community causes pinnacles to swell, expanding laminae thickness and creating distinctive cylindrical bases and cuspate tops. This change in shape suggests that pinnacle morphology emerges from a specific distribution of biomass accumulation that depends on multiple microbial communities fixing carbon in different parts of pinnacles. Similarly, complex patterns of biomass accumulation may be reflected in the morphology of elaborate ancient stromatolites. © 2016 John Wiley & Sons Ltd.

Relationship between increasing concentrations of two carcinogens and statistical image descriptors of foci morphology in the cell transformation assay.

PubMed

Callegaro, Giulia; Corvi, Raffaella; Salovaara, Susan; Urani, Chiara; Stefanini, Federico M

2017-06-01

Cell Transformation Assays (CTAs) have long been proposed for the identification of chemical carcinogenicity potential. The endpoint of these in vitro assays is represented by the phenotypic alterations in cultured cells, which are characterized by the change from the non-transformed to the transformed phenotype. Despite the wide fields of application and the numerous advantages of CTAs, their use in regulatory toxicology has been limited in part due to concerns about the subjective nature of visual scoring, i.e. the step in which transformed colonies or foci are evaluated through morphological features. An objective evaluation of morphological features has been previously obtained through automated digital processing of foci images to extract the value of three statistical image descriptors. In this study a further potential of the CTA using BALB/c 3T3 cells is addressed by analysing the effect of increasing concentrations of two known carcinogens, benzo[a]pyrene and NiCl 2 , with different modes of action on foci morphology. The main result of our quantitative evaluation shows that the concentration of the considered carcinogens has an effect on foci morphology that is statistically significant for the mean of two among the three selected descriptors. Statistical significance also corresponds to visual relevance. The statistical analysis of variations in foci morphology due to concentration allowed to quantify morphological changes that can be visually appreciated but not precisely determined. Therefore, it has the potential of providing new quantitative parameters in CTAs, and of exploiting all the information encoded in foci. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

A Facile Methodology for Engineering the Morphology of CsPbX3 Perovskite Nanocrystals under Ambient Condition

NASA Astrophysics Data System (ADS)

Seth, Sudipta; Samanta, Anunay

2016-11-01

A facile and highly reproducible room temperature, open atmosphere synthesis of cesium lead halide perovskite nanocrystals of six different morphologies is reported just by varying the solvent, ligand and reaction time. Sequential evolution of the quantum dots, nanoplates and nanobars in one medium and nanocubes, nanorods and nanowires in another medium is demonstrated. These perovskite nanoparticles are shown to be of excellent crystalline quality with high fluorescence quantum yield. A mechanism of the formation of nanoparticles of different shapes and sizes is proposed. Considering the key role of morphology in nanotechnology, this simple method of fabrication of a wide range of high quality nanocrystals of different shapes and sizes of all-inorganic lead halide perovskites, whose potential is already demonstrated in light emitting and photovoltaic applications, is likely to help widening the scope and utility of these materials in optoelectronic devices.

Morphologies, Processing and Properties of Ceramic Foams from Pre-Ceramic Foams from Pre-Ceramic Polymer Routes

NASA Technical Reports Server (NTRS)

Stackpoole, Mairead; Simoes, Conan R.; Venkatapathy, Ethiras (Technical Monitor)

2002-01-01

The current research is focused on processing ceramic foams that have potential as a thermal protection material. Ceramic foams with different architectures were formed from the pyrolysis of pre-ceramic polymers at 1200 C in different atmospheres. In some systems a sacrificial polyurethane was used as the blowing agent. We have also processed foams using sacrificial fillers to introduce controlled cell sizes. Each sacrificial filler or blowing agent leads to a unique morphology. The effect of different fillers on foam morphologies will be presented. The presentation will also focus on characterization of these foams in terms of mechanical and thermal properties. Foams processed using these approaches having bulk densities ranging from 0.15 to 0.9 g per cubic centimeter and a cell sizes from 5 to 500 micrometers. Compression strengths ranged from 2 to 7 MPa for these materials.

The morphology and adhesion mechanism of Octopus vulgaris suckers.

PubMed

Tramacere, Francesca; Beccai, Lucia; Kuba, Michael; Gozzi, Alessandro; Bifone, Angelo; Mazzolai, Barbara

2013-01-01

The octopus sucker represents a fascinating natural system performing adhesion on different terrains and substrates. Octopuses use suckers to anchor the body to the substrate or to grasp, investigate and manipulate objects, just to mention a few of their functions. Our study focuses on the morphology and adhesion mechanism of suckers in Octopus vulgaris. We use three different techniques (MRI, ultrasonography, and histology) and a 3D reconstruction approach to contribute knowledge on both morphology and functionality of the sucker structure in O. vulgaris. The results of our investigation are two-fold. First, we observe some morphological differences with respect to the octopus species previously studied (i.e., Octopus joubini, Octopus maya, Octopus bimaculoides/bimaculatus and Eledone cirrosa). In particular, in O. vulgaris the acetabular chamber, that is a hollow spherical cavity in other octopuses, shows an ellipsoidal cavity which roof has an important protuberance with surface roughness. Second, based on our findings, we propose a hypothesis on the sucker adhesion mechanism in O. vulgaris. We hypothesize that the process of continuous adhesion is achieved by sealing the orifice between acetabulum and infundibulum portions via the acetabular protuberance. We suggest this to take place while the infundibular part achieves a completely flat shape; and, by sustaining adhesion through preservation of sucker configuration. In vivo ultrasonographic recordings support our proposed adhesion model by showing the sucker in action. Such an underlying physical mechanism offers innovative potential cues for developing bioinspired artificial adhesion systems. Furthermore, we think that it could possibly represent a useful approach in order to investigate any potential difference in the ecology and in the performance of adhesion by different species.

The Morphology and Adhesion Mechanism of Octopus vulgaris Suckers

PubMed Central

Tramacere, Francesca; Beccai, Lucia; Kuba, Michael; Gozzi, Alessandro; Bifone, Angelo; Mazzolai, Barbara

2013-01-01

The octopus sucker represents a fascinating natural system performing adhesion on different terrains and substrates. Octopuses use suckers to anchor the body to the substrate or to grasp, investigate and manipulate objects, just to mention a few of their functions. Our study focuses on the morphology and adhesion mechanism of suckers in Octopus vulgaris. We use three different techniques (MRI, ultrasonography, and histology) and a 3D reconstruction approach to contribute knowledge on both morphology and functionality of the sucker structure in O. vulgaris. The results of our investigation are two-fold. First, we observe some morphological differences with respect to the octopus species previously studied (i.e., Octopus joubini, Octopus maya, Octopus bimaculoides/bimaculatus and Eledone cirrosa). In particular, in O. vulgaris the acetabular chamber, that is a hollow spherical cavity in other octopuses, shows an ellipsoidal cavity which roof has an important protuberance with surface roughness. Second, based on our findings, we propose a hypothesis on the sucker adhesion mechanism in O. vulgaris. We hypothesize that the process of continuous adhesion is achieved by sealing the orifice between acetabulum and infundibulum portions via the acetabular protuberance. We suggest this to take place while the infundibular part achieves a completely flat shape; and, by sustaining adhesion through preservation of sucker configuration. In vivo ultrasonographic recordings support our proposed adhesion model by showing the sucker in action. Such an underlying physical mechanism offers innovative potential cues for developing bioinspired artificial adhesion systems. Furthermore, we think that it could possibly represent a useful approach in order to investigate any potential difference in the ecology and in the performance of adhesion by different species. PMID:23750233

Different characteristics of mesenchymal stem cells isolated from different layers of full term placenta

PubMed Central

Ha, Chul-Won; Kim, Jin A; Heo, Jin-Chul; Han, Woo-Jung; Oh, Soo-Young; Choi, Suk-Joo

2017-01-01

Background The placenta is a very attractive source of mesenchymal stem cells (MSCs) for regenerative medicine due to readily availability, non-invasive acquisition, and avoidance of ethical issues. Isolating MSCs from parts of placenta tissue has obtained growing interest because they are assumed to exhibit different proliferation and differentiation potentials due to complex structures and functions of the placenta. The objective of this study was to isolate MSCs from different parts of the placenta and compare their characteristics. Methods Placenta was divided into amniotic epithelium (AE), amniotic membrane (AM), chorionic membrane (CM), chorionic villi (CV), chorionic trophoblast without villi (CT-V), decidua (DC), and whole placenta (Pla). Cells isolated from each layer were subjected to analyses for their morphology, proliferation ability, surface markers, and multi-lineage differentiation potential. MSCs were isolated from all placental layers and their characteristics were compared. Findings Surface antigen phenotype, morphology, and differentiation characteristics of cells from all layers indicated that they exhibited properties of MSCs. MSCs from different placental layers had different proliferation rates and differentiation potentials. MSCs from CM, CT-V, CV, and DC had better population doubling time and multi-lineage differentiation potentials compared to those from other layers. Conclusions Our results indicate that MSCs with different characteristics can be isolated from all layers of term placenta. These finding suggest that it is necessary to appropriately select MSCs from different placental layers for successful and consistent outcomes in clinical applications. PMID:28225815

Effect of captivity on morphology: negligible changes in external morphology mask significant changes in internal morphology

PubMed Central

Munn, Adam J.; Byrne, Phillip G.

2018-01-01

Captive breeding programmes are increasingly relied upon for threatened species management. Changes in morphology can occur in captivity, often with unknown consequences for reintroductions. Few studies have examined the morphological changes that occur in captive animals compared with wild animals. Further, the effect of multiple generations being maintained in captivity, and the potential effects of captivity on sexual dimorphism remain poorly understood. We compared external and internal morphology of captive and wild animals using house mouse (Mus musculus) as a model species. In addition, we looked at morphology across two captive generations, and compared morphology between sexes. We found no statistically significant differences in external morphology, but after one generation in captivity there was evidence for a shift in the internal morphology of captive-reared mice; captive-reared mice (two generations bred) had lighter combined kidney and spleen masses compared with wild-caught mice. Sexual dimorphism was maintained in captivity. Our findings demonstrate that captive breeding can alter internal morphology. Given that these morphological changes may impact organismal functioning and viability following release, further investigation is warranted. If the morphological change is shown to be maladaptive, these changes would have significant implications for captive-source populations that are used for reintroduction, including reduced survivorship.

Morphomechanics of bacterial biofilms undergoing anisotropic differential growth

NASA Astrophysics Data System (ADS)

Zhang, Cheng; Li, Bo; Huang, Xiao; Ni, Yong; Feng, Xi-Qiao

2016-10-01

Growing bacterial biofilms exhibit a number of surface morphologies, e.g., concentric wrinkles, radial ridges, and labyrinthine networks, depending on their physiological status and nutrient access. We explore the mechanisms underlying the emergence of these greatly different morphologies. Ginzburg-Landau kinetic method and Fourier spectral method are integrated to simulate the morphological evolution of bacterial biofilms. It is shown that the morphological instability of biofilms is triggered by the stresses induced by anisotropic and heterogeneous bacterial expansion, and involves the competition between membrane energy and bending energy. Local interfacial delamination further enriches the morphologies of biofilms. Phase diagrams are established to reveal how the anisotropy and spatial heterogeneity of growth modulate the surface patterns. The mechanics of three-dimensional microbial morphogenesis may also underpin self-organization in other development systems and provide a potential strategy for engineering microscopic structures from bacterial aggregates.

Anterior cruciate ligament- and hamstring tendon-derived cells: in vitro differential properties of cells involved in ACL reconstruction.

PubMed

Ghebes, Corina Adriana; Kelder, Cindy; Schot, Thomas; Renard, Auke J; Pakvis, Dean F M; Fernandes, Hugo; Saris, Daniel B

2017-04-01

Anterior cruciate ligament (ACL) reconstruction involves the replacement of the torn ligament with a new graft, often a hamstring tendon (HT). Described as similar, the ACL and HT have intrinsic differences related to their distinct anatomical locations. From a cellular perspective, identifying these differences represents a step forward in the search for new cues that enhance recovery after the reconstruction. The purpose of this study was to characterize the phenotype and multilineage potential of ACL- and HT-derived cells. ACL- and HT-derived cells were isolated from tissue harvest from patients undergoing total knee arthroplasty (TKA) or ACL reconstruction. In total, three ACL and three HT donors were investigated. Cell morphology, self-renewal potential (CFU-F), surface marker profiling, expression of tendon/ligament-related markers (PCR) and multilineage potential were analysed for both cell types; both had fibroblast-like morphology and low self-renewal potential. No differences in the expression of tendon/ligament-related genes or a selected set of surface markers were observed between the two cell types. However, differences in their multilineage potential were observed: while ACL-derived cells showed a high potential to differentiate into chondrocytes and adipocytes, but not osteoblasts, HT-derived cells showed poor potential to form adipocytes, chondrocytes and osteoblasts. Our results demonstrated that HT-derived cells have low multilineage potential compared to ACL-derived cells, further highlighting the need for extrinsic signals to fully restore the function of the ACL upon reconstruction. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Fabrication of porous anodic alumina using normal anodization and pulse anodization

NASA Astrophysics Data System (ADS)

Chin, I. K.; Yam, F. K.; Hassan, Z.

2015-05-01

This article reports on the fabrication of porous anodic alumina (PAA) by two-step anodizing the low purity commercial aluminum sheets at room temperature. Different variations of the second-step anodization were conducted: normal anodization (NA) with direct current potential difference; pulse anodization (PA) alternate between potential differences of 10 V and 0 V; hybrid pulse anodization (HPA) alternate between potential differences of 10 V and -2 V. The method influenced the film homogeneity of the PAA and the most homogeneous structure was obtained via PA. The morphological properties are further elucidated using measured current-transient profiles. The absent of current rise profile in PA indicates the anodization temperature and dissolution of the PAA structure were greatly reduced by alternating potential differences.

De novo comparative transcriptome analysis of genes involved in fruit morphology of pumpkin cultivars with extreme size difference and development of EST-SSR markers.

PubMed

Xanthopoulou, Aliki; Ganopoulos, Ioannis; Psomopoulos, Fotis; Manioudaki, Maria; Moysiadis, Theodoros; Kapazoglou, Aliki; Osathanunkul, Maslin; Michailidou, Sofia; Kalivas, Apostolos; Tsaftaris, Athanasios; Nianiou-Obeidat, Irini; Madesis, Panagiotis

2017-07-30

The genetic basis of fruit size and shape was investigated for the first time in Cucurbita species and genetic loci associated with fruit morphology have been identified. Although extensive genomic resources are available at present for tomato (Solanum lycopersicum), cucumber (Cucumis sativus), melon (Cucumis melo) and watermelon (Citrullus lanatus), genomic databases for Cucurbita species are limited. Recently, our group reported the generation of pumpkin (Cucurbita pepo) transcriptome databases from two contrasting cultivars with extreme fruit sizes. In the current study we used these databases to perform comparative transcriptome analysis in order to identify genes with potential roles in fruit morphology and fruit size. Differential Gene Expression (DGE) analysis between cv. 'Munchkin' (small-fruit) and cv. 'Big Moose' (large-fruit) revealed a variety of candidate genes associated with fruit morphology with significant differences in gene expression between the two cultivars. In addition, we have set the framework for generating EST-SSR markers, which discriminate different C. pepo cultivars and show transferability to related Cucurbitaceae species. The results of the present study will contribute to both further understanding the molecular mechanisms regulating fruit morphology and furthermore identifying the factors that determine fruit size. Moreover, they may lead to the development of molecular marker tools for selecting genotypes with desired morphological traits. Copyright © 2017. Published by Elsevier B.V.

[Patterns of action potential firing in cortical neurons of neonatal mice and their electrophysiological property].

PubMed

Furong, Liu; Shengtian, L I

2016-05-25

To investigate patterns of action potential firing in cortical heurons of neonatal mice and their electrophysiological properties. The passive and active membrane properties of cortical neurons from 3-d neonatal mice were observed by whole-cell patch clamp with different voltage and current mode. Three patterns of action potential firing were identified in response to depolarized current injection. The effects of action potential firing patterns on voltage-dependent inward and outward current were found. Neurons with three different firing patterns had different thresholds of depolarized current. In the morphology analysis of action potential, the three type neurons were different in rise time, duration, amplitude and threshold of the first action potential evoked by 80 pA current injection. The passive properties were similar in three patterns of action potential firing. These results indicate that newborn cortical neurons exhibit different patterns of action potential firing with different action potential parameters such as shape and threshold.

The influence of rock strength on erosion processes and river morphology in central Arizona: the accumulation of damage from macro-abrasion

NASA Astrophysics Data System (ADS)

Larimer, J. E.; Yanites, B.

2017-12-01

River morphology reflects the interaction between the driving forces of erosion and the resisting properties of bedrock that limit erosion. Changes in energy dissipation at the riverbed are indicated by differences in channel geometry. To erode at the same rate, stronger rocks require more energy, and thus, an adjustment in river slope or width is necessary to accomplish this work. Therefore, morphological changes should reflect differences in the rock strength properties most relevant to the dominant erosion process. We investigate this hypothesis by comparing river morphology and rock-strength properties of reaches subject to different processes. Streams in Prescott National Forest, AZ expose bedrock through a variety of lithologies, which provides a natural testing ground. Measurements include channel geometry, surface P-wave velocity, fracture spacing, and bedload grain size distribution of 150 individual reaches, as well as 260 tensile and compressive-strength tests and P-wave velocity of cores up to depths of 20 cm. Based on observations, we infer that fluvial erosion processes in this region generally fall into three domains: (1) grain by grain abrasion, (2) progressive failure by damage accumulation due to bedload impacts or `macro-abrasion', and (3) `plucking' of jointed rocks. We focus analyses on the accumulation of damage from sub-critical stresses that weakens the surface of the bedrock, potentially leading to macroscopic fractures, fatigue, and rock failure. This plays a dual role facilitating the ease with which abrasion removes material and increasing the rate of production of pluck-able particles. We estimate the `damage potential' of saltating bedload using water discharge time-series, sediment transport models and grain size distribution. To determine the resistance to damage accumulation among different rocks, we measure the evolution of damage in core samples under uniaxial loading using strain energy and inherent flaw theory. Preliminary results suggest that tensile strength is a good predictor of channel morphology in abrasion dominated reaches, morphology is better predicted through a damage perspective in macro-abrasion dominated reaches, and reduction in P-wave velocity near the surface correlates with damage susceptibility.

Morphological and Molecular Identification of Anagrus ‘atomus’ Group (Hymenoptera: Mymaridae) Individuals from Different Geographic Areas and Plant Hosts in Europe

PubMed Central

Zanolli, P.; Martini, M.; Mazzon, L.; Pavan, F.

2016-01-01

Morphological identification and molecular study on the COI gene were simultaneously conducted on Anagrus Haliday ‘atomus’ group individuals collected in the field in Italy or supplied from a UK biofactory. Females were morphologically identified as A. atomus L. and A. parvus Soyka sensu Viggiani (=A. ustulatus sensu Chiappini). Alignment of COI gene sequences from this study permitted recognition of a total of 34 haplotypes. Phylogenetic and network analyses of molecular data not only confirmed that A. atomus is a species distinct from A. parvus, but also suggested that two species may be included within morphologically identified A. parvus. Different geographical distribution and frequency of haplotypes were also evidenced. For males considered in this study, morphometric analyses revealed a character that could be useful to discriminate A. atomus from A. parvus. Both species were found in vineyards and surrounding vegetation, confirming the potential role of spontaneous vegetation as a source of parasitoids for leafhopper control in vineyards. PMID:27126961

Morphological changes in the cellulose and lignin components of biomass occur at different stages of steam pretreatment

DOE PAGES

Pingali, Sai Venkatesh; O'Neill, Hugh Michael; Nishiyama, Yoshiharu; ...

2014-01-09

Morphological changes to the different components of lignocellulosic biomass were observed as they occurred during steam pretreatment by placing a pressure reaction cell in a neutron beam and collecting time-resolved neutron scattering data. Changes to cellulose morphology occurred mainly in the heating phase, whereas changes in lignin morphology occurred mainly in the holding and cooling phases. During the heating stage, water is irreversibly expelled from cellulose microfibrils as the elementary fibrils coalesce. During the holding phase lignin aggregates begin to appear and they increase in size most noticeably during the cooling phase. This experiment demonstrates the unique information that inmore » situ small angle neutron scattering studies of pretreatment can provide. This approach is potentially useful in optimizing the heating, holding and cooling stages of pretreatments to allow the exact size and nature of lignin aggregates to be controlled in order to enhance enzyme accessibility to cellulose and therefore the efficiency of biomass conversion.« less

Differences in Lateral Line Morphology between Hatchery- and Wild-Origin Steelhead

PubMed Central

Brown, Andrew D.; Sisneros, Joseph A.; Jurasin, Tyler; Nguyen, Chau; Coffin, Allison B.

2013-01-01

Despite identification of multiple factors mediating salmon survival, significant disparities in survival-to-adulthood among hatchery- versus wild-origin juveniles persist. In the present report, we explore the hypothesis that hatchery-reared juveniles might exhibit morphological defects in vulnerable mechanosensory systems prior to release from the hatchery, potentiating reduced survival after release. Juvenile steelhead (Oncorhynchus mykiss) from two different hatcheries were compared to wild-origin juveniles on several morphological traits including lateral line structure, otolith composition (a proxy for auditory function), and brain weight. Wild juveniles were found to possess significantly more superficial lateral line neuromasts than hatchery-reared juveniles, although the number of hair cells within individual neuromasts was not significantly different across groups. Wild juveniles were also found to possess primarily normal, aragonite-containing otoliths, while hatchery-reared juveniles possessed a high proportion of crystallized (vaterite) otoliths. Finally, wild juveniles were found to have significantly larger brains than hatchery-reared juveniles. These differences together predict reduced sensitivity to biologically important hydrodynamic and acoustic signals from natural biotic (predator, prey, conspecific) and abiotic (turbulent flow, current) sources among hatchery-reared steelhead, in turn predicting reduced survival fitness after release. Physiological and behavioral studies are required to establish the functional significance of these morphological differences. PMID:23554988

Local versus Generalized Phenotypes in Two Sympatric Aurelia Species: Understanding Jellyfish Ecology Using Genetics and Morphometrics

PubMed Central

Chiaverano, Luciano M.; Bayha, Keith W.; Graham, William M.

2016-01-01

For individuals living in environmentally heterogeneous environments, a key component for adaptation and persistence is the extent of phenotypic differentiation in response to local environmental conditions. In order to determine the extent of environmentally induced morphological variation in a natural population distributed along environmental gradients, it is necessary to account for potential genetic differences contributing to morphological differentiation. In this study, we set out to quantify geographic morphological variation in the moon jellyfish Aurelia exposed at the extremes of a latitudinal environmental gradient in the Gulf of Mexico (GoM). We used morphological data based on 28 characters, and genetic data taken from mitochondrial cytochrome oxidase I (COI) and nuclear internal transcribed spacer 1 (ITS-1). Molecular analyses revealed the presence of two genetically distinct species of Aurelia co-occurring in the GoM: Aurelia sp. 9 and Aurelia c.f. sp. 2, named for its divergence from (for COI) and similarity to (for ITS-1) Aurelia sp. 2 (Brazil). Neither species exhibited significant population genetic structure between the Northern and the Southeastern Gulf of Mexico; however, they differed greatly in the degree of geographic morphological variation. The morphology of Aurelia sp. 9 exhibited ecophenotypic plasticity and varied significantly between locations, while morphology of Aurelia c.f. sp. 2 was geographically invariant (i.e., canalized). The plastic, generalist medusae of Aurelia sp. 9 are likely able to produce environmentally-induced, “optimal” phenotypes that confer high relative fitness in different environments. In contrast, the non-plastic generalist individuals of Aurelia c.f. sp. 2 likely produce environmentally-independent phenotypes that provide the highest fitness across environments. These findings suggest the two Aurelia lineages co-occurring in the GoM were likely exposed to different past environmental conditions (i.e., different selective pressures) and evolved different strategies to cope with environmental variation. This study highlights the importance of using genetics and morphometric data to understand jellyfish ecology, evolution and systematics. PMID:27332545

Local versus Generalized Phenotypes in Two Sympatric Aurelia Species: Understanding Jellyfish Ecology Using Genetics and Morphometrics.

PubMed

Chiaverano, Luciano M; Bayha, Keith W; Graham, William M

2016-01-01

For individuals living in environmentally heterogeneous environments, a key component for adaptation and persistence is the extent of phenotypic differentiation in response to local environmental conditions. In order to determine the extent of environmentally induced morphological variation in a natural population distributed along environmental gradients, it is necessary to account for potential genetic differences contributing to morphological differentiation. In this study, we set out to quantify geographic morphological variation in the moon jellyfish Aurelia exposed at the extremes of a latitudinal environmental gradient in the Gulf of Mexico (GoM). We used morphological data based on 28 characters, and genetic data taken from mitochondrial cytochrome oxidase I (COI) and nuclear internal transcribed spacer 1 (ITS-1). Molecular analyses revealed the presence of two genetically distinct species of Aurelia co-occurring in the GoM: Aurelia sp. 9 and Aurelia c.f. sp. 2, named for its divergence from (for COI) and similarity to (for ITS-1) Aurelia sp. 2 (Brazil). Neither species exhibited significant population genetic structure between the Northern and the Southeastern Gulf of Mexico; however, they differed greatly in the degree of geographic morphological variation. The morphology of Aurelia sp. 9 exhibited ecophenotypic plasticity and varied significantly between locations, while morphology of Aurelia c.f. sp. 2 was geographically invariant (i.e., canalized). The plastic, generalist medusae of Aurelia sp. 9 are likely able to produce environmentally-induced, "optimal" phenotypes that confer high relative fitness in different environments. In contrast, the non-plastic generalist individuals of Aurelia c.f. sp. 2 likely produce environmentally-independent phenotypes that provide the highest fitness across environments. These findings suggest the two Aurelia lineages co-occurring in the GoM were likely exposed to different past environmental conditions (i.e., different selective pressures) and evolved different strategies to cope with environmental variation. This study highlights the importance of using genetics and morphometric data to understand jellyfish ecology, evolution and systematics.

Convergent Evolution of Unique Morphological Adaptations to a Subterranean Environment in Cave Millipedes (Diplopoda)

PubMed Central

Golovatch, Sergei; Wesener, Thomas; Tian, Mingyi

2017-01-01

Animal life in caves has fascinated researchers and the public alike because of the unusual and sometimes bizarre morphological adaptations observed in numerous troglobitic species. Despite their worldwide diversity, the adaptations of cave millipedes (Diplopoda) to a troglobitic lifestyle have rarely been examined. In this study, morphological characters were analyzed in species belonging to four different orders (Glomerida, Polydesmida, Chordeumatida, and Spirostreptida) and six different families (Glomeridae, Paradoxosomatidae, Polydesmidae, Haplodesmidae, Megalotylidae, and Cambalopsidae) that represent the taxonomic diversity of class Diplopoda. We focused on the recently discovered millipede fauna of caves in southern China. Thirty different characters were used to compare cave troglobites and epigean species within the same genera. A character matrix was created to analyze convergent evolution of cave adaptations. Males and females were analyzed independently to examine sex differences in cave adaptations. While 10 characters only occurred in a few phylogenetic groups, 20 characters were scored for in all families. Of these, four characters were discovered to have evolved convergently in all troglobitic millipedes. The characters that represented potential morphological cave adaptations in troglobitic species were: (1) a longer body; (2) a lighter body color; (3) elongation of the femora; and (4) elongation of the tarsi of walking legs. Surprisingly, female, but not male, antennae were more elongated in troglobites than in epigean species. Our study clearly shows that morphological adaptations have evolved convergently in different, unrelated millipede orders and families, most likely as a direct adaptation to cave life. PMID:28178274

Convergent Evolution of Unique Morphological Adaptations to a Subterranean Environment in Cave Millipedes (Diplopoda).

PubMed

Liu, Weixin; Golovatch, Sergei; Wesener, Thomas; Tian, Mingyi

2017-01-01

Animal life in caves has fascinated researchers and the public alike because of the unusual and sometimes bizarre morphological adaptations observed in numerous troglobitic species. Despite their worldwide diversity, the adaptations of cave millipedes (Diplopoda) to a troglobitic lifestyle have rarely been examined. In this study, morphological characters were analyzed in species belonging to four different orders (Glomerida, Polydesmida, Chordeumatida, and Spirostreptida) and six different families (Glomeridae, Paradoxosomatidae, Polydesmidae, Haplodesmidae, Megalotylidae, and Cambalopsidae) that represent the taxonomic diversity of class Diplopoda. We focused on the recently discovered millipede fauna of caves in southern China. Thirty different characters were used to compare cave troglobites and epigean species within the same genera. A character matrix was created to analyze convergent evolution of cave adaptations. Males and females were analyzed independently to examine sex differences in cave adaptations. While 10 characters only occurred in a few phylogenetic groups, 20 characters were scored for in all families. Of these, four characters were discovered to have evolved convergently in all troglobitic millipedes. The characters that represented potential morphological cave adaptations in troglobitic species were: (1) a longer body; (2) a lighter body color; (3) elongation of the femora; and (4) elongation of the tarsi of walking legs. Surprisingly, female, but not male, antennae were more elongated in troglobites than in epigean species. Our study clearly shows that morphological adaptations have evolved convergently in different, unrelated millipede orders and families, most likely as a direct adaptation to cave life.

One Dimensional Graphitic Carbon Nitrides as Effective Metal-Free Oxygen Reduction Catalysts

PubMed Central

Tahir, Muhammad; Mahmood, Nasir; Zhu, Jinghan; Mahmood, Asif; Butt, Faheem K.; Rizwan, Syed; Aslam, Imran; Tanveer, M.; Idrees, Faryal; Shakir, Imran; Cao, Chuanbao; Hou, Yanglong

2015-01-01

To explore the effect of morphology on catalytic properties of graphitic carbon nitride (GCN), we have studied oxygen reduction reaction (ORR) performance of two different morphologies of GCN in alkaline media. Among both, tubular GCN react with dissolved oxygen in the ORR with an onset potential close to commercial Pt/C. Furthermore, the higher stability and excellent methanol tolerance of tubular GCN compared to Pt/C emphasizes its suitability for fuel cells. PMID:26201998

Morphological, molecular and phylogenetic analyses of Diplotriaena bargusinica Skrjabin, 1917 (Nematoda: Diplotriaenidae).

PubMed

Dutra Vieira, Thainá; Pegoraro de Macedo, Marcia Raquel; Fedatto Bernardon, Fabiana; Müller, Gertrud

2017-10-01

The nematode Diplotriaena bargusinica is a bird air sac parasite, and its taxonomy is based mainly on morphological and morphometric characteristics. Increasing knowledge of genetic information variability has spurred the use of DNA markers in conjunction with morphological data for inferring phylogenetic relationships in different taxa. Considering the potential of molecular biology in taxonomy, this study presents the morphological and molecular characterization of D. bargusinica, and establishes the phylogenetic position of the nematode in Spirurina. Twenty partial sequences of the 18S region of D. bargusinica rDNA were generated. Phylogenetic trees were obtained through the Maximum Likelihood and Bayesian Inference methods where both had similar topology. The group Diplotriaenoidea is monophyletic and the topologies generated corroborate the phylogenetic studies based on traditional and previously performed molecular taxonomy. This study is the first to generate molecular data associated with the morphology of the species. Copyright © 2017 Elsevier B.V. All rights reserved.

Channel morphology effect on water transport through graphene bilayers.

PubMed

Liu, Bo; Wu, Renbing; Law, Adrian Wing-Keung; Feng, Xi-Qiao; Bai, Lichun; Zhou, Kun

2016-12-08

The application of few-layered graphene-derived functional thin films for molecular filtration and separation has recently attracted intensive interests. In practice, the morphology of the nanochannel formed by the graphene (GE) layers is not ideally flat and can be affected by various factors. This work investigates the effect of channel morphology on the water transport behaviors through the GE bilayers via molecular dynamics simulations. The simulation results show that the water flow velocity and transport resistance highly depend on the curvature of the graphene layers, particularly when they are curved in non-synergic patterns. To understand the channel morphology effect, the distributions of water density, dipole moment orientation and hydrogen bonds inside the channel are investigated, and the potential energy surface with different distances to the basal GE layer is analyzed. It shows that the channel morphology significantly changes the distribution of the water molecules and their orientation and interaction inside the channel. The energy barrier for water molecules transport through the channel also significantly depends on the channel morphology.

Channel morphology effect on water transport through graphene bilayers

PubMed Central

Liu, Bo; Wu, Renbing; Law, Adrian Wing-Keung; Feng, Xi-Qiao; Bai, Lichun; Zhou, Kun

2016-01-01

The application of few-layered graphene-derived functional thin films for molecular filtration and separation has recently attracted intensive interests. In practice, the morphology of the nanochannel formed by the graphene (GE) layers is not ideally flat and can be affected by various factors. This work investigates the effect of channel morphology on the water transport behaviors through the GE bilayers via molecular dynamics simulations. The simulation results show that the water flow velocity and transport resistance highly depend on the curvature of the graphene layers, particularly when they are curved in non-synergic patterns. To understand the channel morphology effect, the distributions of water density, dipole moment orientation and hydrogen bonds inside the channel are investigated, and the potential energy surface with different distances to the basal GE layer is analyzed. It shows that the channel morphology significantly changes the distribution of the water molecules and their orientation and interaction inside the channel. The energy barrier for water molecules transport through the channel also significantly depends on the channel morphology. PMID:27929106

Intra-Trackway Morphological Variations Due to Substrate Consistency: The El Frontal Dinosaur Tracksite (Lower Cretaceous, Spain)

PubMed Central

Razzolini, Novella L.; Vila, Bernat; Castanera, Diego; Falkingham, Peter L.; Barco, José Luis; Canudo, José Ignacio; Manning, Phillip L.; Galobart, Àngel

2014-01-01

An ichnological and sedimentological study of the El Frontal dinosaur tracksite (Early Cretaceous, Cameros basin, Soria, Spain) highlights the pronounced intra-trackway variation found in track morphologies of four theropod trackways. Photogrammetric 3D digital models revealed various and distinct intra-trackway morphotypes, which reflect changes in footprint parameters such as the pace length, the track length, depth, and height of displacement rims. Sedimentological analyses suggest that the original substrate was non-homogenous due to lateral changes in adjoining microfacies. Multidata analyses indicate that morphological differences in these deep and shallow tracks represent a part of a continuum of track morphologies and geometries produced by a gradient of substrate consistencies across the site. This implies that the large range of track morphologies at this site resulted from similar trackmakers crossing variable facies. The trackways at the El Frontal site present an exemplary case of how track morphology, and consequently potential ichnotaxa, can vary, even when produced by a single trackmaker. PMID:24699696

Influence of the applied potentials difference on structural and conductive properties of CoZnO nanotubes

NASA Astrophysics Data System (ADS)

Ibragimova, M. A.; Kozlovskiy, A. L.; Kenzhina, I. E.; Zdorovets, M. V.

2018-04-01

A series of CoZnO nanotubes was obtained by electrochemical deposition, with different atomic metal coefficients, due to a change in the applied potential difference. A systematic study of the morphology, structural and conductive properties of nanotubes was also carried out. It is established that the samples synthesized at the applied potentials difference of 1.5 and 1.75 V are three-component systems consisting of two oxide phases of ZnO and CoO1.92 cubic system and a phase of a solid solution of substitution Co0.65Zn0.35 of hexagonal type. The samples synthesized at a potential difference of 2.0 V represent an alloy of two oxide phases, ZnO and CoO1.92.

A non-invasive geometric morphometrics method for exploring variation in dorsal head shape in urodeles: sexual dimorphism and geographic variation in Salamandra salamandra.

PubMed

Alarcón-Ríos, Lucía; Velo-Antón, Guillermo; Kaliontzopoulou, Antigoni

2017-04-01

The study of morphological variation among and within taxa can shed light on the evolution of phenotypic diversification. In the case of urodeles, the dorso-ventral view of the head captures most of the ontogenetic and evolutionary variation of the entire head, which is a structure with a high potential for being a target of selection due to its relevance in ecological and social functions. Here, we describe a non-invasive procedure of geometric morphometrics for exploring morphological variation in the external dorso-ventral view of urodeles' head. To explore the accuracy of the method and its potential for describing morphological patterns we applied it to two populations of Salamandra salamandra gallaica from NW Iberia. Using landmark-based geometric morphometrics, we detected differences in head shape between populations and sexes, and an allometric relationship between shape and size. We also determined that not all differences in head shape are due to size variation, suggesting intrinsic shape differences across sexes and populations. These morphological patterns had not been previously explored in S. salamandra, despite the high levels of intraspecific diversity within this species. The methodological procedure presented here allows to detect shape variation at a very fine scale, and solves the drawbacks of using cranial samples, thus increasing the possibilities of using collection specimens and alive animals for exploring dorsal head shape variation and its evolutionary and ecological implications in urodeles. J. Morphol. 278:475-485, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Virtual taphonomy using synchrotron tomographic microscopy reveals cryptic features and internal structure of modern and fossil plants

PubMed Central

Smith, Selena Y.; Collinson, Margaret E.; Rudall, Paula J.; Simpson, David A.; Marone, Federica; Stampanoni, Marco

2009-01-01

While more commonly applied in zoology, synchrotron radiation X-ray tomographic microscopy (SRXTM) is well-suited to nondestructive study of the morphology and anatomy of both fossil and modern plants. SRXTM uses hard X-rays and a monochromatic light source to provide high-resolution data with little beam-hardening, resulting in slice data with clear boundaries between materials. Anatomy is readily visualized, including various planes of section from a single specimen, as clear as in traditional histological sectioning at low magnifications. Thus, digital sectioning of rare or difficult material is possible. Differential X-ray attenuation allows visualization of different layers or chemistries to enable virtual 3-dimensional (3D) dissections of material. Virtual potential fossils can be visualized and digital tissue removal reveals cryptic underlying morphology. This is essential for fossil identification and for comparisons between assemblages where fossils are preserved by different means. SRXTM is a powerful approach for botanical studies using morphology and anatomy. The ability to gain search images in both 2D and 3D for potential fossils gives paleobotanists a tool—virtual taphonomy—to improve our understanding of plant evolution and paleobiogeography. PMID:19574457

Controlled release of tocopherols from polymer blend films

NASA Astrophysics Data System (ADS)

Obinata, Noe

Controlled release packaging has great potential to increase storage stability of foods by releasing active compounds into foods continuously over time. However, a major limitation in development of this technology is the inability to control the release and provide rates useful for long term storage of foods. Better understanding of the factors affecting active compound release is needed to overcome this limitation. The objective of this research was to investigate the relationship between polymer composition, polymer processing method, polymer morphology, and release properties of active compounds, and to provide proof of principle that compound release is controlled by film morphology. A natural antioxidant, tocopherol was used as a model active compound because it is natural, effective, heat stable, and soluble in most packaging polymers. Polymer blend films were produced from combination of linear low density polyethylene (LLDPE) and high density polyethylene (HDPE), polypropylene (PP), or polystyrene (PS) with 3000 ppm mixed tocopherols using conventional blending method and innovative blending method, smart blending with a novel mixer using chaotic advection. Film morphologies were visualized with scanning electron microscopy (SEM). Release of tocopherols into 95% ethanol as a food simulant was measured by UV/Visible spectrophotometry or HPLC, and diffusivity of tocopherols in the polymers was estimated from this data. Polymer composition (blend proportions) and processing methods have major effects on film morphology. Four different types of morphologies, dispersed, co-continuous, fiber, and multilayer structures were developed by either conventional extrusion or smart blending. With smart blending of fixed polymer compositions, different morphologies were progressively developed with fixed polymer composition as the number of rod rotations increased, providing a way to separate effects of polymer composition and morphology. The different morphologies obtained using conventional and smart blending greatly affected tocopherol release. Strong correlation was observed between morphology and release rate: multilayer, slow release; co-continuous and fiber, moderate; disperse: fast release. Results indicate that morphology can be manipulated by polymer composition and processing method, and release rates of tocopherols are varied with polymer morphology. Manipulating polymer compositions and film morphologies may provide a means to control the release of tocopherols from food contact films.

Comparative morphology of the scales of roundscale spearfish Tetrapturus georgii and white marlin Kajikia albida.

PubMed

Loose, E L; Hilton, E J; Graves, J E

2017-04-01

The comparative morphology of the scales of roundscale spearfish Tetrapturus georgii and white marlin Kajikia albida was investigated. In addition, variation in scale morphology across different body regions within each species was analysed. Although considerable morphological variation was observed among scales from different body regions in both species, scales of K. albida generally have pointed anterior ends, fewer posterior points and are more heavily imbricated than those of T. georgii, which are frequently rounded anteriorly, often have many posterior points and are separated farther within the skin. In all sampled body regions and individuals, scales of T. georgii are significantly broader and have a lower length-to-width aspect ratio than those of K. albida. Superficial to the scales are denticular plates, which are ossified formations occurring on the surface layer of the epidermis; these were observed and described for T. georgii, K. albida and blue marlin Makaira nigricans. Detailed scale descriptions allow for a more accurate characterization of the variation within and differences between these two species and could potentially be a valuable tool for investigating istiophorid systematics. © 2017 The Fisheries Society of the British Isles.

In-Situ through-Plane Measurements of Ionic Potential Distributions in Non-Precious Metal Catalyst Electrode for PEFC

DOE PAGES

Komini Babu, S.; Chung, H. T.; Zelenay, P.; ...

2015-09-14

This manuscript presents micro-scale experimental diagnostics and nano-scale resolution X-ray imaging applied to the study of proton conduction in non-precious metal catalyst (NPMC) fuel cell cathodes. NPMC’s have the potential to reduce the cost of the fuel cell for multiple applications. But, NPMC electrodes are inherently thick compared to the convention Pt/C electrode due to the lower volumetric activity. Thus, the electric potential drop through the Nafion across the electrode thickness can yield significant performance loss. Ionomer distributions in the NPMC electrodes with different ionomer loading are extracted from morphological data using nanoscale X-ray computed tomography (nano-XCT) imaging of themore » cathode. Microstructured electrode scaffold (MES) diagnostics are used to measure the electrolyte potential at discrete points across the thickness of the catalyst layer. When using that apparatus, the electrolyte potential drop, the through-thickness reaction distribution, and the proton conductivity are measured and correlated with the corresponding Nafion morphology and cell performance.« less

The correlation of sperm morphology with unexplained recurrent spontaneous abortion: A systematic review and meta-analysis

PubMed Central

Cao, Xiaodan; Cui, Yun; Zhang, Xiaoxia; Lou, Jiangtao; Zhou, Jun; Wei, Renxiong

2017-01-01

Sperm morphology displays a potential impact on sperm function and may ultimately impact reproductive function. Current studies have investigated the correlation between sperm morphology with unexplained recurrent spontaneous abortion (RSA) but have shown inconsistent results. Hence, we systematically searched MEDLINE, EMBASE, CNKI databases, as well as the Cochrane Library for studies that examined the association between sperm morphology and unexplained RSA. Fifteen studies were identified, including 883 cases and 530 controls. Our meta-analysis results indicated that the percentage of normal sperm morphology from men with RSA partners was significantly lower than those from normal controls(SMD [95% CI]: − 0.60 [−0.81, −0.40]; P<0.00001) and the percentage of sperm morphologic alterations was significantly higher in patients with RSA compared with the control group (SMD [95% CI]: 0.92 [0.42, 1.43]; P=0.0004). The present study suggested that the percentage of normal sperm morphology may indeed decrease in men from RSA group compared with controls. However, there were some limitations in the study such as the differences in stain techniques and classification criteria. Further evidences are needed to better elucidate the relationship between sperm morphology and unexplained RSA. PMID:28903451

Three-dimensional geometric morphometric analysis of talar morphology in extant gorilla taxa from highland and lowland habitats.

PubMed

Knigge, Ryan P; Tocheri, Matthew W; Orr, Caley M; Mcnulty, Kieran P

2015-01-01

Western gorillas (Gorilla gorilla) are known to climb significantly more often than eastern gorillas (Gorilla beringei), a behavioral distinction attributable to major differences in their respective habitats (i.e., highland vs. lowland). Genetic evidence suggests that the lineages leading to these taxa began diverging from one another between approximately 1 and 3 million years ago. Thus, gorillas offer a special opportunity to examine the degree to which morphology of recently diverged taxa may be "fine-tuned" to differing ecological requirements. Using three-dimensional (3D) geometric morphometrics, we compared talar morphology in a sample of 87 specimens including western (lowland), mountain (highland), and grauer gorillas (lowland and highland populations). Talar shape was captured with a series of landmarks and semilandmarks superimposed by generalized Procrustes analysis. A between-group principal components analysis of overall talar shape separates gorillas by ecological habitat and by taxon. An analysis of only the trochlea and lateral malleolar facet identifies subtle variations in trochlear shape between western lowland and lowland grauer gorillas, potentially indicative of convergent evolution of arboreal adaptations in the talus. Lastly, talar shape scales differently with centroid size for highland and lowland gorillas, suggesting that ankle morphology may track body-size mediated variation in arboreal behaviors differently depending on ecological setting. Several of the observed shape differences are linked biomechanically to the facilitation of climbing in lowland gorillas and to stability and load-bearing on terrestrial substrates in the highland taxa, providing an important comparative model for studying morphological variation in groups known only from fossils (e.g., early hominins). © 2014 Wiley Periodicals, Inc.

Photomorphogenesis in Sinningia speciosa, cv. Queen Victoria I. Characterization of Phytochrome Control.

PubMed

Satter, R L; Wetherell, D F

1968-06-01

The morphological development of Sinningia speciosa plants that were exposed to supplementary far red light was very different from that of plants receiving dark nights. After several nights of such irradiation, stems and petioles were elongated, petioles were angulated, leaf blade expansion was inhibited, plants were chlorotic and the accumulation of shoot dry weight was retarded.Red reversibility of the morphological changes potentiated by far red light indicated control by the phytochrome system. A high P(FR) level during the last half of the night inhibited stem elongation and promoted leaf blade expansion, but both of these processes were hardly affected by the P(FR) level during the first half of the night. Thus sensitivity to P(FR) was cyclic.The interpretation of our experiments was complicated by quantitative morphological differences resulting from long, as compared to short, far red irradiations.

The impact of long-term water stress on relative growth rate and morphology of needles and shoots of Metasequoia glyptostroboides seedlings: research toward identifying mechanistic models.

PubMed

Zhang, Yanxiang; Equiza, Maria Alejandra; Zheng, Quanshui; Tyree, Melvin T

2011-09-01

Leaf morphology in the upper canopy of trees tends to be different from that lower down. The effect of long-term water stress on leaf growth and morphology was studied in seedlings of Metasequoia glyptostroboides to understand how tree height might affect leaf morphology in larger trees. Tree height increases water stress on growing leaves through increased hydraulic resistance to water flow and increased gravitational potential, hence we assume that water stress imposed by soil dehydration will have an effect equivalent to stress induced by height. Seedlings were subjected to well-watered and two constant levels of long-term water stress treatments. Drought treatment significantly reduced final needle count, area and mass per area (leaf mass area, LMA) and increased needle density. Needles from water-stressed plants had lower maximum volumetric elastic modulus (ε(max)), osmotic potential at full turgor (Ψ¹⁰⁰(π)) (and at zero turgor (Ψ⁰(π)) (than those from well-watered plants. Palisade and spongy mesophyll cell size and upper epidermal cell size decreased significantly in drought treatments. Needle relative growth rate, needle length and cell sizes were linear functions of the daily average water potential at the time of leaf growth (r² 0.88-0.999). We conclude that water stress alone does mimic the direction and magnitude of changes in leaf morphology observed in tall trees. The results are discussed in terms of various models for leaf growth rate. Copyright © Physiologia Plantarum 2011.

Interaction between Water and Wind as a Driver of Passive Dispersal in Mangroves

PubMed Central

Van der Stocken, Tom; Vanschoenwinkel, Bram; De Ryck, Dennis J. R.; Bouma, Tjeerd J.; Dahdouh-Guebas, Farid; Koedam, Nico

2015-01-01

Although knowledge on dispersal patterns is essential for predicting long-term population dynamics, critical information on the modalities of passive dispersal and potential interactions between vectors is often missing. Here, we use mangrove propagules with a wide variety of morphologies to investigate the interaction between water and wind as a driver of passive dispersal. We imposed 16 combinations of wind and hydrodynamic conditions in a flume tank, using propagules of six important mangrove species (and genera), resulting in a set of dispersal morphologies that covers most variation present in mangrove propagules worldwide. Additionally, we discussed the broader implications of the outcome of this flume study on the potential of long distance dispersal for mangrove propagules in nature, applying a conceptual model to a natural mangrove system in Gazi Bay (Kenya). Overall, the effect of wind on dispersal depended on propagule density (g l-1). The low-density Heritiera littoralis propagules were most affected by wind, while the high-density vertically floating propagules of Ceriops tagal and Bruguiera gymnorrhiza were least affected. Avicennia marina, and horizontally floating Rhizophora mucronata and C. tagal propagules behaved similarly. Morphological propagule traits, such as the dorsal sail of H. littoralis, explained another part of the interspecific differences. Within species, differences in dispersal velocities can be explained by differences in density and for H. littoralis also by variations in the shape of the dorsal sail. Our conceptual model illustrates that different propagule types have a different likelihood of reaching the open ocean depending on prevailing water and wind currents. Results suggest that in open water, propagule traits (density, morphology, and floating orientation) appear to determine the effect of water and wind currents on dispersal dynamics. This has important implications for inter- and intraspecific variation in dispersal patterns and the likelihood of reaching suitable habitat patches within a propagule's viable period. PMID:25811191

Mathematical modelling of the antibiotic-induced morphological transition of Pseudomonas aeruginosa

PubMed Central

Keen, Emma; Smith, David J.

2018-01-01

Here we formulate a mechanistic mathematical model to describe the growth dynamics of P. aeruginosa in the presence of the β-lactam antibiotic meropenem. The model is mechanistic in the sense that carrying capacity is taken into account through the dynamics of nutrient availability rather than via logistic growth. In accordance with our experimental results we incorporate a sub-population of cells, differing in morphology from the normal bacillary shape of P. aeruginosa bacteria, which we assume have immunity from direct antibiotic action. By fitting this model to experimental data we obtain parameter values that give insight into the growth of a bacterial population that includes different cell morphologies. The analysis of two parameters sets, that produce different long term behaviour, allows us to manipulate the system theoretically in order to explore the advantages of a shape transition that may potentially be a mechanism that allows P. aeruginosa to withstand antibiotic effects. Our results suggest that inhibition of this shape transition may be detrimental to bacterial growth and thus suggest that the transition may be a defensive mechanism implemented by bacterial machinery. In addition to this we provide strong theoretical evidence for the potential therapeutic strategy of using antimicrobial peptides (AMPs) in combination with meropenem. This proposed combination therapy exploits the shape transition as AMPs induce cell lysis by forming pores in the cytoplasmic membrane, which becomes exposed in the spherical cells. PMID:29481562

To feed or to breed: morphological constraints of mouthbrooding in coral reef cardinalfishes

PubMed Central

Hoey, Andrew S.; Bellwood, David R.; Barnett, Adam

2012-01-01

Functionally coupled biomechanical systems are widespread in nature and are viewed as major constraints on evolutionary diversification, yet there have been few attempts to explore the implications of performing multiple functions within a single anatomical structure. Paternally mouthbrooding cardinalfishes present an ideal system to investigate the constraints of functional coupling as the oral jaws of male fishes are directly responsible for both feeding and reproductive functions. To test the effects of (i) mouthbrooding on feeding and (ii) feeding on reproductive potential we compared the feeding apparatus between sexes of nine species of cardinalfish and compared brood characteristics among species from different trophic groups, respectively. Mouthbrooding was strongly associated with the morphology of the feeding apparatus in males. Male cardinalfishes possessed longer heads, snouts and jaws than female conspecifics irrespective of body size, trophic group or evolutionary history. Conversely, reproductive potential also appeared to be related to trophic morphology. Piscivorous cardinalfishes produced larger, but fewer eggs, and had smaller brood volumes than species from the two invertebrate feeding groups. These interrelationships suggest that feeding and reproduction in the mouth of cardinalfishes may be tightly coupled. If so this may, in part, have contributed to the limited morphological diversification exhibited by cardinalfishes. PMID:22319124

Influence of channel morphology and flow regime on larval drift of pallid sturgeon in the Lower Missouri River

USGS Publications Warehouse

Erwin, Susannah O.; Jacobson, Robert B.

2015-01-01

The transition from drifting free embryo to exogenously feeding larvae has been identified as a potential life-stage bottleneck for the endangered Missouri River pallid sturgeon. Previous studies have indicated that river regulation and fragmentation may contribute to the mortality of larval pallid sturgeon by reducing the extent of free-flowing river available to free embryos to complete ontogenetic development. Calculations of total drift distance based on mean velocity, however, do not address the potential for complex channels and flow patterns to increase retention or longitudinal dispersion of free embryos. We use a one-dimensional advection–dispersion model to estimate total drift distance and employ the longitudinal dispersion coefficient as a metric to quantify the tendency towards dispersion or retention of passively drifting larvae. We describe the effects of different styles of channel morphology on larval dispersion and consider the implications of flow regime modifications on retention of free embryos within the Lower Missouri River. The results illustrate the complex interactions of local morphology, engineered structures, and hydraulics that determine patterns of dispersion in riverine environments and inform how changes to channel morphology and flow regime may alter dispersion of drifting organisms.

To feed or to breed: morphological constraints of mouthbrooding in coral reef cardinalfishes.

PubMed

Hoey, Andrew S; Bellwood, David R; Barnett, Adam

2012-06-22

Functionally coupled biomechanical systems are widespread in nature and are viewed as major constraints on evolutionary diversification, yet there have been few attempts to explore the implications of performing multiple functions within a single anatomical structure. Paternally mouthbrooding cardinalfishes present an ideal system to investigate the constraints of functional coupling as the oral jaws of male fishes are directly responsible for both feeding and reproductive functions. To test the effects of (i) mouthbrooding on feeding and (ii) feeding on reproductive potential we compared the feeding apparatus between sexes of nine species of cardinalfish and compared brood characteristics among species from different trophic groups, respectively. Mouthbrooding was strongly associated with the morphology of the feeding apparatus in males. Male cardinalfishes possessed longer heads, snouts and jaws than female conspecifics irrespective of body size, trophic group or evolutionary history. Conversely, reproductive potential also appeared to be related to trophic morphology. Piscivorous cardinalfishes produced larger, but fewer eggs, and had smaller brood volumes than species from the two invertebrate feeding groups. These interrelationships suggest that feeding and reproduction in the mouth of cardinalfishes may be tightly coupled. If so this may, in part, have contributed to the limited morphological diversification exhibited by cardinalfishes.

Electrocatalytic reduction of carbon dioxide on electrodeposited tin-based surfaces

NASA Astrophysics Data System (ADS)

Alba, Bianca Christina S.; Camayang, John Carl A.; Mopon, Marlon L.; del Rosario, Julie Anne D.

2017-08-01

The electrocatalytic reduction of carbon dioxide to small organic molecular compounds provides a means of generating alternative fuel source while suppressing climate change. Suitable catalysts, however, are necessary to optimize its reaction kinetics towards more valuable products. Consequently, in this study, electrodeposited Sn electrodes have been developed as catalysts for CO2 electroreduction. Deposition potential was varied to produce different Sn catalysts. SEM showed varying morphologies and increasing amount as the applied potential becomes more negative. Cyclic voltammetry and chronoamperometry showed that the activity and stability of the catalysts towards CO2 reduction depend on the morphology and presence of tin oxides. These results provide a better understanding on the performance of electrodeposited Sn-based surfaces as catalysts for CO2 reduction.

Behavior of Human Bone Marrow-Derived Mesenchymal Stem Cells on Various Titanium-Based Coatings

PubMed Central

Qu, Chengjuan; Kaitainen, Salla; Kröger, Heikki; Lappalainen, Reijo; Lammi, Mikko J.

2016-01-01

The chemical composition and texture of titanium coatings can influence the growth characteristics of the adhered cells. An enhanced proliferation of the human mesenchymal stem cells (hMSCs) would be beneficial. The present study was aimed to investigate whether titanium deposited at different atmospheres would affect the cell growth properties, cellular morphology, and expression of surface markers of hMSCs. Titanium-based coatings were deposited on silicon wafers under oxygen, nitrogen, or argon atmospheres by ultra-short pulsed laser deposition using two different gas pressures followed by heating at 400 °C for 2 h. The characteristics of the coated surfaces were determined via contact angle, zeta potential, and scanning electron microscopy (SEM) techniques. Human MSCs were cultivated on differently coated silicon wafers for 48 h. Subsequently, the cell proliferation rates were analyzed with an MTT assay. The phenotype of hMSCs was checked via immunocytochemical stainings of MSC-associated markers CD73, CD90, and CD105, and the adhesion, spreading, and morphology of hMSCs on coated materials via SEM. The cell proliferation rates of the hMSCs were similar on all coated silicon wafers. The hMSCs retained the MSC phenotype by expressing MSC-associated markers and fibroblast-like morphology with cellular projections. Furthermore, no significant differences could be found in the size of the cells when cultured on all various coated surfaces. In conclusion, despite certain differences in the contact angles and the zeta potentials of various titanium-based coatings, no single coating markedly improved the growth characteristics of hMSCs. PMID:28773947

Unipolar atrial electrogram morphology from an epicardial and endocardial perspective.

PubMed

van der Does, Lisette J M E; Knops, Paul; Teuwen, Christophe P; Serban, Corina; Starreveld, Roeliene; Lanters, Eva A H; Mouws, Elisabeth M J P; Kik, Charles; Bogers, Ad J J C; de Groot, Natasja M S

2018-02-22

Endo-epicardial asynchrony (EEA) and the interplay between the endocardial and epicardial layers could be important in the pathophysiology of atrial arrhythmias. The morphologic differences between epicardial and endocardial atrial electrograms have not yet been described, and electrogram morphology may hold information about the presence of EEA. The purpose of this study was to directly compare epicardial to endocardial unipolar electrogram morphology during sinus rhythm (SR) and to evaluate whether EEA contributes to electrogram fractionation by correlating fractionation to spatial activation patterns. In 26 patients undergoing cardiac surgery, unipolar electrograms were simultaneously recorded from the epicardium and endocardium at the inferior, middle, and superior right atrial (RA) free wall during SR. Potentials were analyzed for epi-endocardial differences in local activation time, voltage, RS ratio, and fractionation. The surrounding and opposite electrograms of fractionated deflections were evaluated for corresponding local activation times in order to determine whether fractionation originated from EEA. The superior RA was predisposed to delayed activation, EEA, and fractionation. Both epicardial and endocardial electrograms demonstrated an S-predominance. Fractionation was mostly similar between the 2 sides; however, incidentally deflections up to 4 mV on 1 side could be absent on the other side. Remote activation was responsible for most fractionated deflections (95%) in SR, of which 4% could be attributed to EEA. Local epi-endocardial differences in electrogram fractionation occur occasionally during SR but will likely increase during arrhythmias due to increasing EEA and (functional) conduction disorders. Electrogram fractionation can originate from EEA, and this study demonstrated that unipolar electrogram fractionation can potentially identify EEA. Copyright © 2018 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Plant traits and decomposition: are the relationships for roots comparable to those for leaves?

PubMed Central

Birouste, Marine; Kazakou, Elena; Blanchard, Alain; Roumet, Catherine

2012-01-01

Background and Aims Fine root decomposition is an important determinant of nutrient and carbon cycling in grasslands; however, little is known about the factors controlling root decomposition among species. Our aim was to investigate whether interspecific variation in the potential decomposition rate of fine roots could be accounted for by root chemical and morphological traits, life history and taxonomic affiliation. We also investigated the co-ordinated variation in root and leaf traits and potential decomposition rates. Methods We analysed potential decomposition rates and the chemical and morphological traits of fine roots on 18 Mediterranean herbaceous species grown in controlled conditions. The results were compared with those obtained for leaves in a previous study conducted on similar species. Key Results Differences in the potential decomposition rates of fine roots between species were accounted for by root chemical composition, but not by morphological traits. The root potential decomposition rate varied with taxonomy, but not with life history. Poaceae, with high cellulose concentration and low concentrations of soluble compounds and phosphorus, decomposed more slowly than Asteraceae and Fabaceae. Patterns of root traits, including decomposition rate, mirrored those of leaf traits, resulting in a similar species clustering. Conclusions The highly co-ordinated variation of roots and leaves in terms of traits and potential decomposition rate suggests that changes in the functional composition of communities in response to anthropogenic changes will strongly affect biogeochemical cycles at the ecosystem level. PMID:22143881

Monolayer to MTS: using SEM, HIM, TEM and SERS to compare morphology, nanosensor uptake and redox potential in MCF7 cells

NASA Astrophysics Data System (ADS)

Jamieson, L. E.; Bell, A. P.; Harrison, D. J.; Campbell, C. J.

2015-06-01

Cellular redox potential is important for the control and regulation of a vast number of processes occurring in cells. When the fine redox potential balance within cells is disturbed it can have serious consequences such as the initiation or progression of disease. It is thought that a redox gradient develops in cancer tumours where the peripheral regions are well oxygenated and internal regions, further from vascular blood supply, become starved of oxygen and hypoxic. This makes treatment of these areas more challenging as, for example, radiotherapy relies on the presence of oxygen. Currently techniques for quantitative analysis of redox gradients are limited. Surface enhanced Raman scattering (SERS) nanosensors (NS) have been used to detect redox potential in a quantitative manner in monolayer cultured cells with many advantages over other techniques. This technique has considerable potential for use in multicellular tumour spheroids (MTS) - a three dimensional (3D) cell model which better mimics the tumour environment and gradients that develop. MTS are a more realistic model of the in vivo cellular morphology and environment and are becoming an increasingly popular in vitro model, replacing traditional monolayer culture. Imaging techniques such as transmission electron microscopy (TEM), scanning electron microscopy (SEM) and helium ion microscopy (HIM) were used to investigate differences in morphology and NS uptake in monolayer culture compared to MTS. After confirming NS uptake, the first SERS measurements revealing quantitative information on redox potential in MTS were performed.

Modeling the Relations Among Morphological Awareness Dimensions, Vocabulary Knowledge, and Reading Comprehension in Adult Basic Education Students

PubMed Central

Tighe, Elizabeth L.; Schatschneider, Christopher

2016-01-01

This study extended the findings of Tighe and Schatschneider (2015) by investigating the predictive utility of separate dimensions of morphological awareness as well as vocabulary knowledge to reading comprehension in adult basic education (ABE) students. We competed two- and three-factor structural equation models of reading comprehension. A three-factor model of real word morphological awareness, pseudoword morphological awareness, and vocabulary knowledge emerged as the best fit and accounted for 79% of the reading comprehension variance. The results indicated that the constructs contributed jointly to reading comprehension; however, vocabulary knowledge was the only potentially unique predictor (p = 0.052), accounting for an additional 5.6% of the variance. This study demonstrates the feasibility of applying a latent variable modeling approach to examine individual differences in the reading comprehension skills of ABE students. Further, this study replicates the findings of Tighe and Schatschneider (2015) on the importance of differentiating among dimensions of morphological awareness in this population. PMID:26869981

Three-Dimensional Morphological and Chemical Evolution of Nanoporous Stainless Steel by Liquid Metal Dealloying [3D Morphological and Chemical Evolution of Nanoporous Stainless Steel by Liquid Metal Dealloying

DOE PAGES

Zhao, Chonghang; Wada, Takeshi; De Andrade, Vincent; ...

2017-09-04

Nanoporous materials, especially those fabricated by liquid metal dealloying processes, possess great potential in a wide range of applications due to their high surface area, bicontinuous structure with both open pores for transport and solid phase for conductivity or support, and low material cost. Here, we used X-ray nanotomography and X-ray fluorescence microscopy to reveal the three-dimensional (3D) morphology and elemental distribution within materials. Focusing on nanoporous stainless steel, we evaluated the 3D morphology of the dealloying front and established a quantitative processing-structure-property relationship at a later stage of dealloying. The morphological differences of samples created by liquid metal dealloyingmore » and aqueous dealloying methods were also discussed. Here, we concluded that it is particularly important to consider the dealloying, coarsening, and densification mechanisms in influencing the performance-determining, critical 3D parameters, such as tortuosity, pore size, porosity, curvature, and interfacial shape.« less

Three-Dimensional Morphological and Chemical Evolution of Nanoporous Stainless Steel by Liquid Metal Dealloying [3D Morphological and Chemical Evolution of Nanoporous Stainless Steel by Liquid Metal Dealloying

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Chonghang; Wada, Takeshi; De Andrade, Vincent

Nanoporous materials, especially those fabricated by liquid metal dealloying processes, possess great potential in a wide range of applications due to their high surface area, bicontinuous structure with both open pores for transport and solid phase for conductivity or support, and low material cost. Here, we used X-ray nanotomography and X-ray fluorescence microscopy to reveal the three-dimensional (3D) morphology and elemental distribution within materials. Focusing on nanoporous stainless steel, we evaluated the 3D morphology of the dealloying front and established a quantitative processing-structure-property relationship at a later stage of dealloying. The morphological differences of samples created by liquid metal dealloyingmore » and aqueous dealloying methods were also discussed. Here, we concluded that it is particularly important to consider the dealloying, coarsening, and densification mechanisms in influencing the performance-determining, critical 3D parameters, such as tortuosity, pore size, porosity, curvature, and interfacial shape.« less

Modeling the Relations Among Morphological Awareness Dimensions, Vocabulary Knowledge, and Reading Comprehension in Adult Basic Education Students.

PubMed

Tighe, Elizabeth L; Schatschneider, Christopher

2016-01-01

This study extended the findings of Tighe and Schatschneider (2015) by investigating the predictive utility of separate dimensions of morphological awareness as well as vocabulary knowledge to reading comprehension in adult basic education (ABE) students. We competed two- and three-factor structural equation models of reading comprehension. A three-factor model of real word morphological awareness, pseudoword morphological awareness, and vocabulary knowledge emerged as the best fit and accounted for 79% of the reading comprehension variance. The results indicated that the constructs contributed jointly to reading comprehension; however, vocabulary knowledge was the only potentially unique predictor (p = 0.052), accounting for an additional 5.6% of the variance. This study demonstrates the feasibility of applying a latent variable modeling approach to examine individual differences in the reading comprehension skills of ABE students. Further, this study replicates the findings of Tighe and Schatschneider (2015) on the importance of differentiating among dimensions of morphological awareness in this population.

Accurate diagnosis of thyroid follicular lesions from nuclear morphology using supervised learning.

PubMed

Ozolek, John A; Tosun, Akif Burak; Wang, Wei; Chen, Cheng; Kolouri, Soheil; Basu, Saurav; Huang, Hu; Rohde, Gustavo K

2014-07-01

Follicular lesions of the thyroid remain significant diagnostic challenges in surgical pathology and cytology. The diagnosis often requires considerable resources and ancillary tests including immunohistochemistry, molecular studies, and expert consultation. Visual analyses of nuclear morphological features, generally speaking, have not been helpful in distinguishing this group of lesions. Here we describe a method for distinguishing between follicular lesions of the thyroid based on nuclear morphology. The method utilizes an optimal transport-based linear embedding for segmented nuclei, together with an adaptation of existing classification methods. We show the method outputs assignments (classification results) which are near perfectly correlated with the clinical diagnosis of several lesion types' lesions utilizing a database of 94 patients in total. Experimental comparisons also show the new method can significantly outperform standard numerical feature-type methods in terms of agreement with the clinical diagnosis gold standard. In addition, the new method could potentially be used to derive insights into biologically meaningful nuclear morphology differences in these lesions. Our methods could be incorporated into a tool for pathologists to aid in distinguishing between follicular lesions of the thyroid. In addition, these results could potentially provide nuclear morphological correlates of biological behavior and reduce health care costs by decreasing histotechnician and pathologist time and obviating the need for ancillary testing. Copyright © 2014 Elsevier B.V. All rights reserved.

Assessment of Mouse Germinal Vesicle Stage Oocyte Quality by Evaluating the Cumulus Layer, Zona Pellucida, and Perivitelline Space

PubMed Central

Liu, Ying-Lei; Chen, Ying; Zhou, Cheng-Jie; Wu, Sha-Na; Shen, Jiang-Peng; Liang, Cheng-Guang

2014-01-01

To improve the outcome of assisted reproductive technology (ART) for patients with ovulation problems, it is necessary to retrieve and select germinal vesicle (GV) stage oocytes with high developmental potential. Oocytes with high developmental potential are characterized by their ability to undergo proper maturation, fertilization, and embryo development. In this study, we analyzed morphological traits of GV stage mouse oocytes, including cumulus cell layer thickness, zona pellucida thickness, and perivitelline space width. Then, we assessed the corresponding developmental potential of each of these oocytes and found that it varies across the range measured for each morphological trait. Furthermore, by manipulating these morphological traits in vitro, we were able to determine the influence of morphological variation on oocyte developmental potential. Manually altering the thickness of the cumulus layer showed strong effects on the fertilization and embryo development potentials of oocytes, whereas manipulation of zona pellucida thickness effected the oocyte maturation potential. Our results provide a systematic detailed method for selecting GV stage oocytes based on a morphological assessment approach that would benefit for several downstream ART applications. PMID:25144310

Correlations between the Dielectric Properties and Exterior Morphology of Cells Revealed by Dielectrophoretic Field-Flow Fractionation

PubMed Central

Gascoyne, Peter R. C.; Shim, Sangjo; Noshari, Jamileh; Becker, Frederick F.; Stemke-Hale, Katherine

2013-01-01

Although dielectrophoresis (DEP) has great potential for addressing clinical cell isolation problems based on cell dielectric differences, a biological basis for predicting the DEP behavior of cells has been lacking. Here, the dielectric properties of the NCI-60 panel of tumor cell types have been measured by dielectrophoretic (DEP) field-flow fractionation, correlated with the exterior morphologies of the cells during growth, and compared with the dielectric and morphological characteristics of the subpopulations of peripheral blood. In agreement with earlier findings, cell total capacitance varied with both cell size and plasma membrane folding and the dielectric properties of the NCI-60 cell types in suspension reflected the plasma membrane area and volume of the cells at their growth sites. Therefore, the behavior of cells in DEP-based manipulations is largely determined by their exterior morphological characteristics prior to release into suspension. As a consequence, DEP is able to discriminate between cells of similar size having different morphological origins, offering a significant advantage over size-based filtering for isolating circulating tumor cells, for example. The findings provide a framework for anticipating cell dielectric behavior on the basis of structure-function relationships and suggest that DEP should be widely applicable as a surface marker-independent method for sorting cells. PMID:23172680

Comparative neuronal morphology of the cerebellar cortex in afrotherians, carnivores, cetartiodactyls, and primates

PubMed Central

Jacobs, Bob; Johnson, Nicholas L.; Wahl, Devin; Schall, Matthew; Maseko, Busisiwe C.; Lewandowski, Albert; Raghanti, Mary A.; Wicinski, Bridget; Butti, Camilla; Hopkins, William D.; Bertelsen, Mads F.; Walsh, Timothy; Roberts, John R.; Reep, Roger L.; Hof, Patrick R.; Sherwood, Chet C.; Manger, Paul R.

2014-01-01

Although the basic morphological characteristics of neurons in the cerebellar cortex have been documented in several species, virtually nothing is known about the quantitative morphological characteristics of these neurons across different taxa. To that end, the present study investigated cerebellar neuronal morphology among eight different, large-brained mammalian species comprising a broad phylogenetic range: afrotherians (African elephant, Florida manatee), carnivores (Siberian tiger, clouded leopard), cetartiodactyls (humpback whale, giraffe) and primates (human, common chimpanzee). Specifically, several neuron types (e.g., stellate, basket, Lugaro, Golgi, and granule neurons; N = 317) of the cerebellar cortex were stained with a modified rapid Golgi technique and quantified on a computer-assisted microscopy system. There was a 64-fold variation in brain mass across species in our sample (from clouded leopard to the elephant) and a 103-fold variation in cerebellar volume. Most dendritic measures tended to increase with cerebellar volume. The cerebellar cortex in these species exhibited the trilaminate pattern common to all mammals. Morphologically, neuron types in the cerebellar cortex were generally consistent with those described in primates (Fox et al., 1967) and rodents (Palay and Chan-Palay, 1974), although there was substantial quantitative variation across species. In particular, Lugaro neurons in the elephant appeared to be disproportionately larger than those in other species. To explore potential quantitative differences in dendritic measures across species, MARSplines analyses were used to evaluate whether species could be differentiated from each other based on dendritic characteristics alone. Results of these analyses indicated that there were significant differences among all species in dendritic measures. PMID:24795574

Neurochemical, morphologic, and laminar characterization of cortical projection neurons in the cingulate motor areas of the macaque monkey

NASA Technical Reports Server (NTRS)

Nimchinsky, E. A.; Hof, P. R.; Young, W. G.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

1996-01-01

The primate cingulate gyrus contains multiple cortical areas that can be distinguished by several neurochemical features, including the distribution of neurofilament protein-enriched pyramidal neurons. In addition, connectivity and functional properties indicate that there are multiple motor areas in the cortex lining the cingulate sulcus. These motor areas were targeted for analysis of potential interactions among regional specialization, connectivity, and cellular characteristics such as neurochemical profile and morphology. Specifically, intracortical injections of retrogradely transported dyes and intracellular injection were combined with immunocytochemistry to investigate neurons projecting from the cingulate motor areas to the putative forelimb region of the primary motor cortex, area M1. Two separate groups of neurons projecting to area M1 emanated from the cingulate sulcus, one anterior and one posterior, both of which furnished commissural and ipsilateral connections with area M1. The primary difference between the two populations was laminar origin, with the anterior projection originating largely in deep layers, and the posterior projection taking origin equally in superficial and deep layers. With regard to cellular morphology, the anterior projection exhibited more morphologic diversity than the posterior projection. Commissural projections from both anterior and posterior fields originated largely in layer VI. Neurofilament protein distribution was a reliable tool for localizing the two projections and for discriminating between them. Comparable proportions of the two sets of projection neurons contained neurofilament protein, although the density and distribution of the total population of neurofilament protein-enriched neurons was very different in the two subareas of origin. Within a projection, the participating neurons exhibited a high degree of morphologic heterogeneity, and no correlation was observed between somatodendritic morphology and neurofilament protein content. Thus, although the neurons that provide the anterior and posterior cingulate motor projections to area M1 differ morphologically and in laminar origin, their neurochemical profiles are similar with respect to neurofilament protein. This suggests that neurochemical phenotype may be a more important unifying feature for corticocortical projections than morphology.

Energetic benefits and adaptations in mammalian limbs: Scale effects and selective pressures.

PubMed

Kilbourne, Brandon M; Hoffman, Louwrens C

2015-06-01

Differences in limb size and shape are fundamental to mammalian morphological diversity; however, their relevance to locomotor costs has long been subject to debate. In particular, it remains unknown if scale effects in whole limb morphology could partially underlie decreasing mass-specific locomotor costs with increasing limb length. Whole fore- and hindlimb inertial properties reflecting limb size and shape-moment of inertia (MOI), mass, mass distribution, and natural frequency-were regressed against limb length for 44 species of quadrupedal mammals. Limb mass, MOI, and center of mass position are negatively allometric, having a strong potential for lowering mass-specific locomotor costs in large terrestrial mammals. Negative allometry of limb MOI results in a 40% reduction in MOI relative to isometry's prediction for our largest sampled taxa. However, fitting regression residuals to adaptive diversification models reveals that codiversification of limb mass, limb length, and body mass likely results from selection for differing locomotor modes of running, climbing, digging, and swimming. The observed allometric scaling does not result from selection for energetically beneficial whole limb morphology with increasing size. Instead, our data suggest that it is a consequence of differing morphological adaptations and body size distributions among quadrupedal mammals, highlighting the role of differing limb functions in mammalian evolution. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

'Ogura'-based 'CMS' lines with different nuclear backgrounds of cabbage revealed substantial diversity at morphological and molecular levels.

PubMed

Parkash, Chander; Kumar, Sandeep; Singh, Rajender; Kumar, Ajay; Kumar, Satish; Dey, Shyam Sundar; Bhatia, Reeta; Kumar, Raj

2018-01-01

A comprehensive study on characterization and genetic diversity analysis was carried out in 16 'Ogura'-based 'CMS' lines of cabbage using 14 agro-morphological traits and 29 SSR markers. Agro-morphological characterization depicted considerable variations for different horticultural traits studied. The genotype, ZHA-2, performed better for most of the economically important quantitative traits. Further, gross head weight (0.76), head length (0.60) and head width (0.83) revealed significant positive correlation with net head weight. Dendrogram based on 10 quantitative traits exhibited considerable diversity among different CMS lines and principle component analysis (PCA) indicated that net and gross head weight, and head length and width are the main components of divergence between 16 CMS lines of cabbage. In molecular study, a total of 58 alleles were amplified by 29 SSR primers, averaging to 2.0 alleles in each locus. High mean values of Shannon's Information index (0.62), expected (0.45) and observed (0.32) heterozygosity and polymorphic information content (0.35) depicted substantial polymorphism. Dendrogram based on Jaccard's similarity coefficient constructed two major groups and eight sub-groups, which revealed substantial diversity among different CMS lines. In overall, based on agro-morphological and molecular studies genotype RRMA, ZHA-2 and RCA were found most divergent. Hence, they have immense potential in future breeding programs for the high-yielding hybrid development in cabbage.

A morphological and functional basis for maximum prey size in piscivorous fishes

PubMed Central

Bellwood, David R.

2017-01-01

Fish predation is important in shaping populations and community structure in aquatic systems. These predator-prey interactions can be influenced by environmental, behavioural and morphological factors. Morphological constraints influence the feeding performance of species, and interspecific differences can thus affect patterns of resource use. For piscivorous fishes that swallow prey whole, feeding performance has traditionally been linked to three key morphological constraints: oral gape, pharyngeal gape, and the cleithral gape. However, other constraints may be important. We therefore examine 18 potential morphological constraints related to prey capture and processing, on four predatory species (Cephalopholis urodeta, Paracirrhites forsteri, Pterois volitans, Lates calcarifer). Aquarium-based experiments were then carried out to determine capture and processing behaviour and maximum prey size in two focal species, C. urodeta and P. forsteri. All four species showed a progressive decrease in gape measurements from anterior to posterior with oral gape ≥ buccal ≥ pharyngeal ≥ pectoral girdle ≥ esophagus ≥ stomach. C. urodeta was able to process prey with a maximum depth of 27% of the predators’ standard length; for P. forsteri it was 20%. C. urodeta captured prey head-first in 79% of successful strikes. In P. forsteri head-first was 16.6%, mid-body 44.4%, and tail-first 38.8%. Regardless of capture mode, prey were almost always swallowed head first and horizontally in both focal species. Most internal measurements appeared too small for prey to pass through. This may reflect the compressibility of prey, i.e. their ability to be dorsoventrally compressed during swallowing movements. Despite examining all known potential morphological constraints on prey size, horizontal maxillary oral gape in a mechanically stretched position appears to be the main morphological variable that is likely to affect maximum prey size and resource use by these predatory species. PMID:28886161

Surfactant-free Synthesis of CuO with Controllable Morphologies and Enhanced Photocatalytic Property

NASA Astrophysics Data System (ADS)

Wang, Xing; Yang, Jiao; Shi, Liuxue; Gao, Meizhen

2016-03-01

A green synthesis for nanoleave, nanosheet, spindle-like, rugby-like, dandelion-like and flower-like CuO nanostructures (from 2D to 3D) is successfully achieved through simply hydrothermal synthetic method without the assistance of surfactant. The morphology of CuO nanostructures can be easily tailored by adjusting the amount of ammonia and the source of copper. By designing a time varying experiment, it is verified that the flower- and dandelion-like CuO structures are synthesized by the self-assembly and Ostwald ripening mechanism. Structural and morphological evolutions are investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-visible diffuse reflectance spectra. Additionally, the CuO nanostructures with different morphologies could serve as a potential photocatalyst on the photodecomposition of rhodamine B (RhB) aqueous solutions in the presence of H2O2 under visible light irradiation.

Systemic estimation of the effect of photodynamic therapy of cancer

NASA Astrophysics Data System (ADS)

Kogan, Eugenia A.; Meerovich, Gennadii A.; Torshina, Nadezgda L.; Loschenov, Victor B.; Volkova, Anna I.; Posypanova, Anna M.

1997-12-01

The effects of photodynamic therapy (PDT) of cancer needs objective estimation and its unification in experimental as well as in clinical studies. They must include not only macroscopical changes but also the complex of following morphological criteria: (1) the level of direct tumor damage (direct necrosis and apoptosis); (2) the level of indirect tumor damage (ischemic necrosis); (3) the signs of vascular alterations; (4) the local and systemic antiblastome resistance; (5) the proliferative activity and malignant potential of survival tumor tissue. We have performed different regimes PDT using phthalocyanine derivatives. The complex of morphological methods (Ki-67, p53, c-myc, bcl-2) was used. Obtained results showed the connection of the tilted morphological criteria with tumor regression.

Morphology and solubility of multiple crystal forms of Taka-amylase A

NASA Astrophysics Data System (ADS)

Ninomiya, Kumiko; Yamamoto, Tenyu; Oheda, Tadashi; Sato, Kiyotaka; Sazaki, Gen; Matsuura, Yoshiki

2001-01-01

An α-amylase originating from a mold Aspergillus oryzae, Taka-amylase A (Mr of 52 kDa, pI of 3.8), has been purified to an electrophoretically single band grade. Crystallization behaviors were investigated using ammonium sulfate and polyethleneglycol 8000 as precipitants. The variations in the morphology of the crystals obtained with changing crystallization parameters are described. Five apparently different crystal forms were obtained, and their morphology and crystallographic data have been determined. Solubility values of four typical forms were measured using a Michelson-type two-beam interferometer. The results of these experiments showed that this protein can be a potentially interesting and useful model for crystal growth study with a gram-amount availability of pure protein sample.

Sex differences of gray matter morphology in cortico-limbic-striatal neural system in major depressive disorder.

PubMed

Kong, Lingtao; Chen, Kaiyuan; Womer, Fay; Jiang, Wenyan; Luo, Xingguang; Driesen, Naomi; Liu, Jie; Blumberg, Hilary; Tang, Yanqing; Xu, Ke; Wang, Fei

2013-06-01

Sex differences are observed in both epidemiological and clinical aspects of major depressive disorder (MDD). The cortico-limbic-striatal neural system, including the prefrontal cortex, amygdala, hippocampus, and striatum, have shown sexually dimorphic morphological features and have been implicated in the dysfunctional regulation of mood and emotion in MDD. In this study, we utilized a whole-brain, voxel-based approach to examine sex differences in the regional distribution of gray matter (GM) morphological abnormalities in medication-naïve participants with MDD. Participants included 29 medication-naïve individuals with MDD (16 females and 13 males) and 33 healthy controls (HC) (17 females and 16 males). Gray matter morphology of the cortico-limbic-striatal neural system was examined using voxel-based morphometry analyzes of high-resolution structural magnetic resonance imaging scans. The main effect of diagnosis and interaction effect of diagnosis by sex on GM morphology were statistically significant (p < 0.05, corrected) in the left ventral prefrontal cortex, right amygdala, right hippocampus and bilateral caudate when comparing the MDD and HC groups. Posthoc analyzes showed that females with MDD had significant GM decreases in limbic regions (p < 0.05, corrected), compared to female HC; while males with MDD demonstrated significant GM reduction in striatal regions, (p < 0.05, corrected), compared to HC males. The observed sex-related patterns of abnormalities within the cortico-limbic-strial neural system, such as predominant prefrontal-limbic abnormalities in MDD females vs. predominant prefrontal-striatal abnormalities in MDD males, suggest differences in neural circuitry that may mediate sex differences in the clinical presentation of MDD and potential targets for sex-differentiated treatment of the disorder. Copyright © 2013 Elsevier Ltd. All rights reserved.

An Assessment of Regional Variations in Martian Modified Impact Crater Morphology

NASA Astrophysics Data System (ADS)

Craddock, Robert A.; Bandeira, Lourenço.; Howard, Alan D.

2018-03-01

Impact craters on Mars have been extensively modified by ancient geologic processes that may have included rainfall and surface runoff, snow and ice, denudation by lava flows, burial by eolian material, or others. Many of these processes can leave distinct signatures on the morphometry of the modified impact crater as well as the surrounding landscape. To look for signs of potential regional differences in crater modification processes, we conducted an analysis of different morphometric parameters related to modified impact craters located in the Margaritifer Sinus, Sinus Sabaeus, Iapygia, Mare Tyrrhenum, Aeolis, and Eridania quadrangles, including depth, crater wall slope, crater floor slope, the curvature between the interior wall and the crater floor slope, and the curvature between the interior wall and surrounding landscape. A Welch's t test analysis comparing these parameters shows that fresh impact craters (Type 4) have consistent morphologies regardless of their geographic location examined in this study, which is not unexpected. Modified impact craters both in the initial (Type 3) and terminal stages (Type 1) of modification also have statistically consistent morphologies. This would suggest that the processes that operated in the late Noachian were globally ubiquitous, and that modified craters eventually reached a stable crater morphology. However, craters preserved in advanced (but not terminal) stages of modification (Type 2) have morphologies that vary across the quadrangles. It is possible that these variations reflect spatial differences in the types and intensity of geologic processes that operated during the Noachian, implying that the ancient climate also varied across regions.

Distinct Visual Evoked Potential Morphological Patterns for Apparent Motion Processing in School-Aged Children.

PubMed

Campbell, Julia; Sharma, Anu

2016-01-01

Measures of visual cortical development in children demonstrate high variability and inconsistency throughout the literature. This is partly due to the specificity of the visual system in processing certain features. It may then be advantageous to activate multiple cortical pathways in order to observe maturation of coinciding networks. Visual stimuli eliciting the percept of apparent motion and shape change is designed to simultaneously activate both dorsal and ventral visual streams. However, research has shown that such stimuli also elicit variable visual evoked potential (VEP) morphology in children. The aim of this study was to describe developmental changes in VEPs, including morphological patterns, and underlying visual cortical generators, elicited by apparent motion and shape change in school-aged children. Forty-one typically developing children underwent high-density EEG recordings in response to a continuously morphing, radially modulated, circle-star grating. VEPs were then compared across the age groups of 5-7, 8-10, and 11-15 years according to latency and amplitude. Current density reconstructions (CDR) were performed on VEP data in order to observe activated cortical regions. It was found that two distinct VEP morphological patterns occurred in each age group. However, there were no major developmental differences between the age groups according to each pattern. CDR further demonstrated consistent visual generators across age and pattern. These results describe two novel VEP morphological patterns in typically developing children, but with similar underlying cortical sources. The importance of these morphological patterns is discussed in terms of future studies and the investigation of a relationship to visual cognitive performance.

Distinct Visual Evoked Potential Morphological Patterns for Apparent Motion Processing in School-Aged Children

PubMed Central

Campbell, Julia; Sharma, Anu

2016-01-01

Measures of visual cortical development in children demonstrate high variability and inconsistency throughout the literature. This is partly due to the specificity of the visual system in processing certain features. It may then be advantageous to activate multiple cortical pathways in order to observe maturation of coinciding networks. Visual stimuli eliciting the percept of apparent motion and shape change is designed to simultaneously activate both dorsal and ventral visual streams. However, research has shown that such stimuli also elicit variable visual evoked potential (VEP) morphology in children. The aim of this study was to describe developmental changes in VEPs, including morphological patterns, and underlying visual cortical generators, elicited by apparent motion and shape change in school-aged children. Forty-one typically developing children underwent high-density EEG recordings in response to a continuously morphing, radially modulated, circle-star grating. VEPs were then compared across the age groups of 5–7, 8–10, and 11–15 years according to latency and amplitude. Current density reconstructions (CDR) were performed on VEP data in order to observe activated cortical regions. It was found that two distinct VEP morphological patterns occurred in each age group. However, there were no major developmental differences between the age groups according to each pattern. CDR further demonstrated consistent visual generators across age and pattern. These results describe two novel VEP morphological patterns in typically developing children, but with similar underlying cortical sources. The importance of these morphological patterns is discussed in terms of future studies and the investigation of a relationship to visual cognitive performance. PMID:27445738

Broiler Breeder Sperm Mobility Phenotype and its Effects on Female Fertility

USDA-ARS?s Scientific Manuscript database

Semen quality in poultry can be characterized by different phenotypic traits including volume, concentration, mobility, viability, and sperm morphology. To date, sperm mobility phenotype has been shown to be the most reliable indicator of male fertilizing potential under artificial insemination (AI...

Morphological Features of the Porcine Lacrimal Gland and Its Compatibility for Human Lacrimal Gland Xenografting

PubMed Central

Gaffling, Simone; Asano, Nagayoshi; Hampel, Ulrike; Garreis, Fabian; Hornegger, Joachim; Paulsen, Friedrich

2013-01-01

In this study, we present first data concerning the anatomical structure, blood supply and location of the lacrimal gland of the pig. Our data indicate that the porcine lacrimal gland may serve as a potential xenograft candidate in humans or as an animal model for engineering of a bioartificial lacrimal gland tissue construct for clinical application. For this purpose, we used different macroscopic preparation techniques and digital reconstruction of the histological gland morphology to gain new insights and important information concerning the feasibility of a lacrimal gland transplantation from pig to humans in general. Our results show that the lacrimal gland of the pig reveals a lot of morphological similarities to the analogous human lacrimal gland and thus might be regarded as a xenograft in the future. This is true for a similar anatomical location within the orbit as well as for the feeding artery supply to the organ. Functional differences concerning the composition of the tear fluid, due to a different secretory unit distribution within the gland tissue will, however, be a challenge in future investigations. PMID:24069265

Morphological features of the porcine lacrimal gland and its compatibility for human lacrimal gland xenografting.

PubMed

Henker, Robert; Scholz, Michael; Gaffling, Simone; Asano, Nagayoshi; Hampel, Ulrike; Garreis, Fabian; Hornegger, Joachim; Paulsen, Friedrich

2013-01-01

In this study, we present first data concerning the anatomical structure, blood supply and location of the lacrimal gland of the pig. Our data indicate that the porcine lacrimal gland may serve as a potential xenograft candidate in humans or as an animal model for engineering of a bioartificial lacrimal gland tissue construct for clinical application. For this purpose, we used different macroscopic preparation techniques and digital reconstruction of the histological gland morphology to gain new insights and important information concerning the feasibility of a lacrimal gland transplantation from pig to humans in general. Our results show that the lacrimal gland of the pig reveals a lot of morphological similarities to the analogous human lacrimal gland and thus might be regarded as a xenograft in the future. This is true for a similar anatomical location within the orbit as well as for the feeding artery supply to the organ. Functional differences concerning the composition of the tear fluid, due to a different secretory unit distribution within the gland tissue will, however, be a challenge in future investigations.

Morphology-controlled preparation of lead powders by electrodeposition from different PbO-containing choline chloride-urea deep eutectic solvent

NASA Astrophysics Data System (ADS)

Ru, Juanjian; Hua, Yixin; Xu, Cunying; Li, Jian; Li, Yan; Wang, Ding; Qi, Cancan; Jie, Yafei

2015-04-01

Lead powders with different morphologies, including corals, rods, wires, needles, ferns and dendritic forms, are prepared by electrodeposition onto a stainless steel substrate from different PbO-containing (10-60 mM) choline chloride-urea deep eutectic solvent at cell voltage 2.5 V and 343 K for 2 h. The electrochemical behavior of the PbO dissolved in this solvent is investigated with cyclic voltammetry. It is demonstrated that the increasing of PbO concentration makes the reduction potential EPb(II)/Pb shift positively and facilitates the electrodeposition of lead from PbO in the deep eutectic solvent. According to the analysis of the morphological and crystallographic characteristics of lead powders, the predominant origin of the growth layers is turned away from centre type towards the edge and corner types with the increase in PbO concentration. Due to the large number of growth centres at higher PbO concentration, fine and irregular grains are observed on the surface of formed particles which results in the development of primary and secondary branches in dendrites.

Trophic divergence despite morphological convergence in a continental radiation of snakes

PubMed Central

Grundler, Michael C.; Rabosky, Daniel L.

2014-01-01

Ecological and phenotypic convergence is a potential outcome of adaptive radiation in response to ecological opportunity. However, a number of factors may limit convergence during evolutionary radiations, including interregional differences in biogeographic history and clade-specific constraints on form and function. Here, we demonstrate that a single clade of terrestrial snakes from Australia—the oxyuranine elapids—exhibits widespread morphological convergence with a phylogenetically diverse and distantly related assemblage of snakes from North America. Australian elapids have evolved nearly the full spectrum of phenotypic modalities that occurs among North American snakes. Much of the convergence appears to involve the recurrent evolution of stereotyped morphologies associated with foraging mode, locomotion and habitat use. By contrast, analysis of snake diets indicates striking divergence in feeding ecology between these faunas, partially reflecting regional differences in ecological allometry between Australia and North America. Widespread phenotypic convergence with the North American snake fauna coupled with divergence in feeding ecology are clear examples of how independent continental radiations may converge along some ecological axes yet differ profoundly along others. PMID:24920479

Trophic divergence despite morphological convergence in a continental radiation of snakes.

PubMed

Grundler, Michael C; Rabosky, Daniel L

2014-07-22

Ecological and phenotypic convergence is a potential outcome of adaptive radiation in response to ecological opportunity. However, a number of factors may limit convergence during evolutionary radiations, including interregional differences in biogeographic history and clade-specific constraints on form and function. Here, we demonstrate that a single clade of terrestrial snakes from Australia--the oxyuranine elapids--exhibits widespread morphological convergence with a phylogenetically diverse and distantly related assemblage of snakes from North America. Australian elapids have evolved nearly the full spectrum of phenotypic modalities that occurs among North American snakes. Much of the convergence appears to involve the recurrent evolution of stereotyped morphologies associated with foraging mode, locomotion and habitat use. By contrast, analysis of snake diets indicates striking divergence in feeding ecology between these faunas, partially reflecting regional differences in ecological allometry between Australia and North America. Widespread phenotypic convergence with the North American snake fauna coupled with divergence in feeding ecology are clear examples of how independent continental radiations may converge along some ecological axes yet differ profoundly along others. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Morphological selection in an extreme flow environment: body shape and waterfall-climbing success in the Hawaiian stream fish Sicyopterus stimpsoni.

PubMed

Blob, Richard W; Bridges, William C; Ptacek, Margaret B; Maie, Takashi; Cediel, Roberto A; Bertolas, Morgan M; Julius, Matthew L; Schoenfuss, Heiko L

2008-12-01

Flow characteristics are a prominent factor determining body shapes in aquatic organisms, and correlations between body shape and ambient flow regimes have been established for many fish species. In this study, we investigated the potential for a brief period of extreme flow to exert selection on the body shape of juvenile climbing Hawaiian gobiid fishes. Because of an amphidromous life history, juvenile gobies that complete an oceanic larval phase return to freshwater habitats, where they become adults. Returning juveniles often must scale waterfalls (typically with the use of a ventral sucker) in order to reach the habitats they will use as adults, thereby exposing these animals to brief periods of extreme velocities of flow. Hydrodynamic theory predicts that bodies with larger suckers and with lower heights that reduce drag would have improved climbing success and, thus, be well suited to meet the demands of the flows in waterfalls. To test the potential for the flow environment of waterfalls to impose selection that could contribute to differences in body shape between islands, we subjected juvenile Sicyopterus stimpsoni to climbing trials up artificial waterfalls (∼100 body lengths) and measured differences in body shape between successful and unsuccessful climbers. Waterfalls appear to represent a significant selective barrier to these fishes, as nearly 30% failed our climbing test. However, the effects of selection on morphology were not straightforward, as significant differences in shape between successful and unsuccessful climbers did not always match hydrodynamic predictions. In both selection experiments and in adult fish collected from habitats with different prevailing conditions of flow (the islands of Hawai'i versus Kaua'i), lower head heights were associated with exposure to high-flow regimes, as predicted by hydrodynamic theory. Thus, a premium appears to be placed on the reduction of drag via head morphology throughout the ontogeny of this species. The congruence of phenotypic selection patterns observed in our experiments, with morphological character divergence documented among adult fish from Hawai'i and Kaua'i, suggests that differences in morphology between subpopulations of adult climbing gobies may result, at least in part, from the selective pressures of high-velocity flows encountered by migrating juveniles.

Integrating environmental, molecular, and morphological data to unravel an ice-age radiation of arctic-alpine Campanula in western North America

PubMed Central

DeChaine, Eric G; Wendling, Barry M; Forester, Brenna R

2014-01-01

Many arctic-alpine plant genera have undergone speciation during the Quaternary. The bases for these radiations have been ascribed to geographic isolation, abiotic and biotic differences between populations, and/or hybridization and polyploidization. The Cordilleran Campanula L. (Campanulaceae Juss.), a monophyletic clade of mostly endemic arctic-alpine taxa from western North America, experienced a recent and rapid radiation. We set out to unravel the factors that likely influenced speciation in this group. To do so, we integrated environmental, genetic, and morphological datasets, tested biogeographic hypotheses, and analyzed the potential consequences of the various factors on the evolutionary history of the clade. We created paleodistribution models to identify potential Pleistocene refugia for the clade and estimated niche space for individual taxa using geographic and climatic data. Using 11 nuclear loci, we reconstructed a species tree and tested biogeographic hypotheses derived from the paleodistribution models. Finally, we tested 28 morphological characters, including floral, vegetative, and seed characteristics, for their capacity to differentiate taxa. Our results show that the combined effect of Quaternary climatic variation, isolation among differing environments in the mountains in western North America, and biotic factors influencing floral morphology contributed to speciation in this group during the mid-Pleistocene. Furthermore, our biogeographic analyses uncovered asynchronous consequences of interglacial and glacial periods for the timing of refugial isolation within the southern and northwestern mountains, respectively. These findings have broad implications for understanding the processes promoting speciation in arctic-alpine plants and the rise of numerous endemic taxa across the region. PMID:25505522

Morphology-flow interactions lead to stage-selective vertical transport of larval sand dollars in shear flow.

PubMed

Clay, T W; Grünbaum, D

2010-04-01

Many larvae and other plankton have complex and variable morphologies of unknown functional significance. We experimentally and theoretically investigated the functional consequences of the complex morphologies of larval sand dollars, Dendraster excentricus (Eschscholtz), for hydrodynamic interactions between swimming and turbulent water motion. Vertical shearing flows (horizontal gradients of vertical flow) tilt organisms with simple geometries (e.g. spheres, ellipsoids), causing these organisms to move horizontally towards downwelling water and compromising their abilities to swim upwards. A biomechanical model of corresponding hydrodynamic interactions between turbulence-induced shear and the morphologically complex four-, six- and eight-armed stages of sand dollar larvae suggests that the movements of larval morphologies differ quantitatively and qualitatively across stages and shear intensities: at shear levels typical of calm conditions in estuarine and coastal environments, all modeled larval stages moved upward. However, at higher shears, modeled four- and eight-armed larvae moved towards downwelling, whereas six-armed larvae moved towards upwelling. We also experimentally quantified larval movement by tracking larvae swimming in low-intensity shear while simultaneously mapping the surrounding flow fields. Four- and eight-armed larvae moved into downwelling water, but six-armed larvae did not. Both the model and experiments suggest that stage-dependent changes to larval morphology lead to differences in larval movement: four- and eight-armed stages are more prone than the six-armed stage to moving into downwelling water. Our results suggest a mechanism by which differences can arise in the vertical distribution among larval stages. The ability to mitigate or exploit hydrodynamic interactions with shear is a functional consequence that potentially shapes larval evolution and development.

Polyploidy and the relationship between leaf structure and function: implications for correlated evolution of anatomy, morphology, and physiology in Brassica.

PubMed

Baker, Robert L; Yarkhunova, Yulia; Vidal, Katherine; Ewers, Brent E; Weinig, Cynthia

2017-01-05

Polyploidy is well studied from a genetic and genomic perspective, but the morphological, anatomical, and physiological consequences of polyploidy remain relatively uncharacterized. Whether these potential changes bear on functional integration or are idiosyncratic remains an open question. Repeated allotetraploid events and multiple genomic combinations as well as overlapping targets of artificial selection make the Brassica triangle an excellent system for exploring variation in the connection between plant structure (anatomy and morphology) and function (physiology). We examine phenotypic integration among structural aspects of leaves including external morphology and internal anatomy with leaf-level physiology among several species of Brassica. We compare diploid and allotetraploid species to ascertain patterns of phenotypic correlations among structural and functional traits and test the hypothesis that allotetraploidy results in trait disintegration allowing for transgressive phenotypes and additional evolutionary and crop improvement potential. Among six Brassica species, we found significant effects of species and ploidy level for morphological, anatomical and physiological traits. We identified three suites of intercorrelated traits in both diploid parents and allotetraploids: Morphological traits (such as leaf area and perimeter) anatomic traits (including ab- and ad- axial epidermis) and aspects of physiology. In general, there were more correlations between structural and functional traits for allotetraploid hybrids than diploid parents. Parents and hybrids did not have any significant structure-function correlations in common. Of particular note, there were no significant correlations between morphological structure and physiological function in the diploid parents. Increased phenotypic integration in the allotetraploid hybrids may be due, in part, to increased trait ranges or simply different structure-function relationships. Genomic and chromosomal instability in early generation allotetraploids may allow Brassica species to explore new trait space and potentially reach higher adaptive peaks than their progenitor species could, despite temporary fitness costs associated with unstable genomes. The trait correlations that disappear after hybridization as well as the novel trait correlations observed in allotetraploid hybrids may represent relatively evolutionarily labile associations and therefore could be ideal targets for artificial selection and crop improvement.

Quantifying Morphological Features of α-U3O8 with Image Analysis for Nuclear Forensics.

PubMed

Olsen, Adam M; Richards, Bryony; Schwerdt, Ian; Heffernan, Sean; Lusk, Robert; Smith, Braxton; Jurrus, Elizabeth; Ruggiero, Christy; McDonald, Luther W

2017-03-07

Morphological changes in U 3 O 8 based on calcination temperature have been quantified enabling a morphological feature to serve as a signature of processing history in nuclear forensics. Five separate calcination temperatures were used to synthesize α-U 3 O 8 , and each sample was characterized using powder X-ray diffraction (p-XRD) and scanning electron microscopy (SEM). The p-XRD spectra were used to evaluate the purity of the synthesized U-oxide; the morphological analysis for materials (MAMA) software was utilized to quantitatively characterize the particle shape and size as indicated by the SEM images. Analysis comparing the particle attributes, such as particle area at each of the temperatures, was completed using the Kolmogorov-Smirnov two sample test (K-S test). These results illustrate a distinct statistical difference between each calcination temperature. To provide a framework for forensic analysis of an unknown sample, the sample distributions at each temperature were compared to randomly selected distributions (100, 250, 500, and 750 particles) from each synthesized temperature to determine if they were statistically different. It was found that 750 particles were required to differentiate between all of the synthesized temperatures with a confidence interval of 99.0%. Results from this study provide the first quantitative morphological study of U-oxides, and reveals the potential strength of morphological particle analysis in nuclear forensics by providing a framework for a more rapid characterization of interdicted uranium oxide samples.

Global morphological analysis of marine viruses shows minimal regional variation and dominance of non-tailed viruses.

PubMed

Brum, Jennifer R; Schenck, Ryan O; Sullivan, Matthew B

2013-09-01

Viruses influence oceanic ecosystems by causing mortality of microorganisms, altering nutrient and organic matter flux via lysis and auxiliary metabolic gene expression and changing the trajectory of microbial evolution through horizontal gene transfer. Limited host range and differing genetic potential of individual virus types mean that investigations into the types of viruses that exist in the ocean and their spatial distribution throughout the world's oceans are critical to understanding the global impacts of marine viruses. Here we evaluate viral morphological characteristics (morphotype, capsid diameter and tail length) using a quantitative transmission electron microscopy (qTEM) method across six of the world's oceans and seas sampled through the Tara Oceans Expedition. Extensive experimental validation of the qTEM method shows that neither sample preservation nor preparation significantly alters natural viral morphological characteristics. The global sampling analysis demonstrated that morphological characteristics did not vary consistently with depth (surface versus deep chlorophyll maximum waters) or oceanic region. Instead, temperature, salinity and oxygen concentration, but not chlorophyll a concentration, were more explanatory in evaluating differences in viral assemblage morphological characteristics. Surprisingly, given that the majority of cultivated bacterial viruses are tailed, non-tailed viruses appear to numerically dominate the upper oceans as they comprised 51-92% of the viral particles observed. Together, these results document global marine viral morphological characteristics, show that their minimal variability is more explained by environmental conditions than geography and suggest that non-tailed viruses might represent the most ecologically important targets for future research.

Auditory attention in childhood and adolescence: An event-related potential study of spatial selective attention to one of two simultaneous stories.

PubMed

Karns, Christina M; Isbell, Elif; Giuliano, Ryan J; Neville, Helen J

2015-06-01

Auditory selective attention is a critical skill for goal-directed behavior, especially where noisy distractions may impede focusing attention. To better understand the developmental trajectory of auditory spatial selective attention in an acoustically complex environment, in the current study we measured auditory event-related potentials (ERPs) across five age groups: 3-5 years; 10 years; 13 years; 16 years; and young adults. Using a naturalistic dichotic listening paradigm, we characterized the ERP morphology for nonlinguistic and linguistic auditory probes embedded in attended and unattended stories. We documented robust maturational changes in auditory evoked potentials that were specific to the types of probes. Furthermore, we found a remarkable interplay between age and attention-modulation of auditory evoked potentials in terms of morphology and latency from the early years of childhood through young adulthood. The results are consistent with the view that attention can operate across age groups by modulating the amplitude of maturing auditory early-latency evoked potentials or by invoking later endogenous attention processes. Development of these processes is not uniform for probes with different acoustic properties within our acoustically dense speech-based dichotic listening task. In light of the developmental differences we demonstrate, researchers conducting future attention studies of children and adolescents should be wary of combining analyses across diverse ages. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Auditory attention in childhood and adolescence: An event-related potential study of spatial selective attention to one of two simultaneous stories

PubMed Central

Karns, Christina M.; Isbell, Elif; Giuliano, Ryan J.; Neville, Helen J.

2015-01-01

Auditory selective attention is a critical skill for goal-directed behavior, especially where noisy distractions may impede focusing attention. To better understand the developmental trajectory of auditory spatial selective attention in an acoustically complex environment, in the current study we measured auditory event-related potentials (ERPs) in human children across five age groups: 3–5 years; 10 years; 13 years; 16 years; and young adults using a naturalistic dichotic listening paradigm, characterizing the ERP morphology for nonlinguistic and linguistic auditory probes embedded in attended and unattended stories. We documented robust maturational changes in auditory evoked potentials that were specific to the types of probes. Furthermore, we found a remarkable interplay between age and attention-modulation of auditory evoked potentials in terms of morphology and latency from the early years of childhood through young adulthood. The results are consistent with the view that attention can operate across age groups by modulating the amplitude of maturing auditory early-latency evoked potentials or by invoking later endogenous attention processes. Development of these processes is not uniform for probes with different acoustic properties within our acoustically dense speech-based dichotic listening task. In light of the developmental differences we demonstrate, researchers conducting future attention studies of children and adolescents should be wary of combining analyses across diverse ages. PMID:26002721

Phylogeny-based comparative methods question the adaptive nature of sporophytic specializations in mosses.

PubMed

Huttunen, Sanna; Olsson, Sanna; Buchbender, Volker; Enroth, Johannes; Hedenäs, Lars; Quandt, Dietmar

2012-01-01

Adaptive evolution has often been proposed to explain correlations between habitats and certain phenotypes. In mosses, a high frequency of species with specialized sporophytic traits in exposed or epiphytic habitats was, already 100 years ago, suggested as due to adaptation. We tested this hypothesis by contrasting phylogenetic and morphological data from two moss families, Neckeraceae and Lembophyllaceae, both of which show parallel shifts to a specialized morphology and to exposed epiphytic or epilithic habitats. Phylogeny-based tests for correlated evolution revealed that evolution of four sporophytic traits is correlated with a habitat shift. For three of them, evolutionary rates of dual character-state changes suggest that habitat shifts appear prior to changes in morphology. This suggests that they could have evolved as adaptations to new habitats. Regarding the fourth correlated trait the specialized morphology had already evolved before the habitat shift. In addition, several other specialized "epiphytic" traits show no correlation with a habitat shift. Besides adaptive diversification, other processes thus also affect the match between phenotype and environment. Several potential factors such as complex genetic and developmental pathways yielding the same phenotypes, differences in strength of selection, or constraints in phenotypic evolution may lead to an inability of phylogeny-based comparative methods to detect potential adaptations.

Influence of carbon nanoparticle modification on the mechanical and electrical properties of epoxy in small volumes.

PubMed

Leopold, Christian; Augustin, Till; Schwebler, Thomas; Lehmann, Jonas; Liebig, Wilfried V; Fiedler, Bodo

2017-11-15

The influence of nanoparticle morphology and filler content on the mechanical and electrical properties of carbon nanoparticle modified epoxy is investigated regarding small volumes. Three types of particles, representing spherical, tubular and layered morphologies are used. A clear size effect of increasing true failure strength with decreasing volume is found for neat and carbon black modified epoxy. Carbon nanotube (CNT) modified epoxy exhibits high potential for strength increase, but dispersion and purity are critical. In few layer graphene modified epoxy, particles are larger than statistically distributed defects and initiate cracks, counteracting any size effect. Different toughness increasing mechanisms on the nano- and micro-scale depending on particle morphology are discussed based on scanning electron microscopy images. Electrical percolation thresholds in the small volume fibres are significantly higher compared to bulk volume, with CNT being found to be the most suitable morphology to form electrical conductive paths. Good correlation between electrical resistance change and stress strain behaviour under tensile loads is observed. The results show the possibility to detect internal damage in small volumes by measuring electrical resistance and therefore indicate to the high potential for using CNT modified polymers in fibre reinforced plastics as a multifunctional, self-monitoring material with improved mechanical properties. Copyright © 2017. Published by Elsevier Inc.

The specific diagnosis of gastrointestinal nematode infections in livestock: larval culture technique, its limitations and alternative DNA-based approaches.

PubMed

Roeber, Florian; Kahn, Lewis

2014-10-15

The specific diagnosis of gastrointestinal nematode infections in ruminants is routinely based on larval culture technique and on the morphological identification of developed third-stage larvae. However, research on the ecology and developmental requirements of different species suggests that environmental conditions (e.g., temperature and humidity) for optimal development to occur vary between the different species. Thus, employing a common culture protocol for all species will favour the development of certain species over others and can cause a biased result in particular when species proportions in a mixed infection are to be determined. Furthermore, the morphological identification of L3 larvae is complicated by a lack of distinctive, obvious features that would allow the identification of all key species. In the present paper we review in detail the potential limitations of larval culture technique and morphological identification and provide account to some modern molecular alternatives to the specific diagnosis of gastrointestinal nematode infection in ruminants. Copyright © 2014 Elsevier B.V. All rights reserved.

Modeling the Lexical Morphology of Western Handwritten Signatures

PubMed Central

Diaz-Cabrera, Moises; Ferrer, Miguel A.; Morales, Aythami

2015-01-01

A handwritten signature is the final response to a complex cognitive and neuromuscular process which is the result of the learning process. Because of the many factors involved in signing, it is possible to study the signature from many points of view: graphologists, forensic experts, neurologists and computer vision experts have all examined them. Researchers study written signatures for psychiatric, penal, health and automatic verification purposes. As a potentially useful, multi-purpose study, this paper is focused on the lexical morphology of handwritten signatures. This we understand to mean the identification, analysis, and description of the signature structures of a given signer. In this work we analyze different public datasets involving 1533 signers from different Western geographical areas. Some relevant characteristics of signature lexical morphology have been selected, examined in terms of their probability distribution functions and modeled through a General Extreme Value distribution. This study suggests some useful models for multi-disciplinary sciences which depend on handwriting signatures. PMID:25860942

Microbiota from Litopenaeus vannamei: digestive tract microbial community of Pacific white shrimp (Litopenaeus vannamei).

PubMed

Tzuc, Jaqueline Tuyub; Escalante, Diana Rendíz; Rojas Herrera, Rafael; Gaxiola Cortés, Gabriela; Ortiz, Maria Leticia Arena

2014-01-01

Bacteria capable of producing different extracellular enzymes of potential relevance in digestive processes were isolated from the stomach, hepatopancreas and intestine of Pacific white shrimp Litopenaeus vannamei. A total of 64 strains with proteolytic activity were isolated and grouped into 16 clusters based on morphological characteristics: 4 groups were isolated from the intestine; 5 from the hepatopancreas; and 7 from the stomach. Molecular methods (16S rRNA gene amplification and sequencing) and phenotypic criteria (Gram stain, catalase and oxidase tests, cell and colony morphology) were used to identify strains, which corresponded to Pseudoalteromonas and Vibrio genera. These genera are reported to form part of the digestive tract microbial community in shrimp. Both genera were isolated from all three tested tissues. One member of each morphologic group was selected for analysis of the presence of amylases, lipases/esterases and chitinases. Most of the strains had all the tested enzymes, indicating that the L. vannamei digestive tract microbiotic flora includes groups which have the potential to contribute to the degradation of dietary components.

Plasma Electrolytic Oxidation Coatings on Pure Ti Substrate: Effects of Na3PO4 Concentration on Morphology and Corrosion Behavior of Coatings in Ringer's Physiological Solution

NASA Astrophysics Data System (ADS)

Roknian, Masoud; Fattah-alhosseini, Arash; Gashti, Seyed Omid

2018-03-01

Plasma electrolytic oxidation has been used as a relatively new method for applying ceramic coatings having different features. In the present study, commercially pure titanium is used as substrate, and effects of trisodium phosphate electrolyte concentration on the microstructure, as well as corrosion behavior of the coating in Ringer's physiological solution are investigated. The morphology and phase compositions of coatings were analyzed by using scanning electron microscopy (SEM) and x-ray diffraction patterns. The study on the corrosion behavior of samples in a Ringer's physiological solution was carried out using open-circuit potential potentiodynamic polarization and electrochemical impedance spectroscopy. The results of electrochemical analysis proved that higher concentration of phosphate electrolyte leads to increase in the corrosion resistance of applied coatings. Accordingly, obtained results revealed that the optimum electrolyte concentration for the best corrosion behavior was 20 g L-1. Furthermore, SEM images and reduction in the dielectric breakdown potential indicated that increase in the electrolyte concentration leads to morphological improvement and smoothening of the surface.

Electrodeposition of gold thin films with controlled morphologies and their applications in electrocatalysis and SERS.

PubMed

Elias, Jamil; Gizowska, Magdalena; Brodard, Pierre; Widmer, Roland; Dehazan, Yoram; Graule, Thomas; Michler, Johann; Philippe, Laetitia

2012-06-29

Here, an easy and effective electrochemical route towards the synthesis of gold thin films with well-controlled roughness, morphology and crystallographic orientation is reported. To control these different factors, the applied potential during deposition played a major role. A tentative nucleation and growth mechanism is demonstrated by means of electrochemical characterizations and a formation mechanism is proposed. Interestingly, the differences in geometry and orientation of the different gold deposits have shown a clear correlation with the electrocatalytical activity in the case of oxygen sensing. In addition, not only the electrocatalytical activity but also the surface-enhanced Raman scattering of the gold deposits have been found to depend both on the roughness and on the size of the surface nanostructures, allowing a fine tuning by controlling these two parameters during deposition.

Electrodeposition of gold thin films with controlled morphologies and their applications in electrocatalysis and SERS

NASA Astrophysics Data System (ADS)

Elias, Jamil; Gizowska, Magdalena; Brodard, Pierre; Widmer, Roland; deHazan, Yoram; Graule, Thomas; Michler, Johann; Philippe, Laetitia

2012-06-01

Here, an easy and effective electrochemical route towards the synthesis of gold thin films with well-controlled roughness, morphology and crystallographic orientation is reported. To control these different factors, the applied potential during deposition played a major role. A tentative nucleation and growth mechanism is demonstrated by means of electrochemical characterizations and a formation mechanism is proposed. Interestingly, the differences in geometry and orientation of the different gold deposits have shown a clear correlation with the electrocatalytical activity in the case of oxygen sensing. In addition, not only the electrocatalytical activity but also the surface-enhanced Raman scattering of the gold deposits have been found to depend both on the roughness and on the size of the surface nanostructures, allowing a fine tuning by controlling these two parameters during deposition.

Crystal growth, structure and morphology of hydrocortisone methanol solvate

NASA Astrophysics Data System (ADS)

Chen, Jianxin; Wang, Jiangkang; Zhang, Ying; Wu, Hong; Chen, Wei; Guo, Zhichao

2004-04-01

Hydrocortisone (HC), an important grucocorticoid, was crystallized from methanol solvent in the form of its methanol solvate. Its crystal structure belongs to orthorhombic, space group P2 12 12 1, with the unit cell parameters a=7.712(3) Å, b=14.392(5) Å, c=18.408(6) Å, Z=4. The methanol takes part in intermolecular hydrogen bonding, so if we change the solvent, the crystal habit of HC maybe different. The long parallelepiped morphology was also predicted by Cerius 2TM simulation program. The influence of intermolecular interaction was taken into account in the attachment energy model. The morphology calculation performed on the potential energy minimized model using a generic DREIDING 2.21 force field and developed minimization protocol with derived partial charges fits the experimental crystal shape well.

Morphological awareness and reading comprehension: Examining mediating factors.

PubMed

Levesque, Kyle C; Kieffer, Michael J; Deacon, S Hélène

2017-08-01

The relation between morphological awareness-defined as the awareness of and ability to manipulate the smallest units of meaning in language-and reading comprehension remains in need of specification. In this study, we evaluated four potential intervening variables through which morphological awareness may contribute indirectly to reading comprehension. We assessed word reading and vocabulary as well as children's ability to read and analyze the meaning of morphologically complex words (morphological decoding and morphological analysis, respectively). Controls of phonological awareness and nonverbal ability were included in the model. Participants were 221 English-speaking children in Grade 3. Multivariate path analyses revealed evidence of two indirect relations and one direct relation between morphological awareness and reading comprehension. In the first indirect path, morphological awareness contributed to morphological decoding, which then influenced word reading and finally reading comprehension. In a second indirect path, morphological awareness contributed to morphological analysis, which contributed to reading comprehension. Finally, in a direct path, morphological awareness contributed to reading comprehension beyond all other variables. These findings inform as to the potential mechanisms underlying the relation between morphological awareness and reading comprehension in children. Copyright © 2017 Elsevier Inc. All rights reserved.

Repeated adaptive divergence of microhabitat specialization in avian feather lice.

PubMed

Johnson, Kevin P; Shreve, Scott M; Smith, Vincent S

2012-06-20

Repeated adaptive radiations are evident when phenotypic divergence occurs within lineages, but this divergence into different forms is convergent when compared across lineages. Classic examples of such repeated adaptive divergence occur in island (for example, Caribbean Anolis lizards) and lake systems (for example, African cichlids). Host-parasite systems in many respects are analogous to island systems, where host species represent isolated islands for parasites whose life cycle is highly tied to that of their hosts. Thus, host-parasite systems might exhibit interesting cases of repeated adaptive divergence as seen in island and lake systems.The feather lice of birds spend their entire life cycle on the body of the host and occupy distinct microhabitats on the host: head, wing, body and generalist. These microhabitat specialists show pronounced morphological differences corresponding to how they escape from host preening. We tested whether these different microhabitat specialists were a case of repeated adaptive divergence by constructing both morphological and molecular phylogenies for a diversity of avian feather lice, including many examples of head, wing, body and generalist forms. Morphological and molecular based phylogenies were highly incongruent, which could be explained by rampant convergence in morphology related to microhabitat specialization on the host. In many cases lice from different microhabitat specializations, but from the same group of birds, were sister taxa. This pattern indicates a process of repeated adaptive divergence of these parasites within host group, but convergence when comparing parasites across host groups. These results suggest that host-parasite systems might be another case in which repeated adaptive radiations could be relatively common, but potentially overlooked, because morphological convergence can obscure evolutionary relationships.

Repeated adaptive divergence of microhabitat specialization in avian feather lice

PubMed Central

2012-01-01

Background Repeated adaptive radiations are evident when phenotypic divergence occurs within lineages, but this divergence into different forms is convergent when compared across lineages. Classic examples of such repeated adaptive divergence occur in island (for example, Caribbean Anolis lizards) and lake systems (for example, African cichlids). Host-parasite systems in many respects are analogous to island systems, where host species represent isolated islands for parasites whose life cycle is highly tied to that of their hosts. Thus, host-parasite systems might exhibit interesting cases of repeated adaptive divergence as seen in island and lake systems. The feather lice of birds spend their entire life cycle on the body of the host and occupy distinct microhabitats on the host: head, wing, body and generalist. These microhabitat specialists show pronounced morphological differences corresponding to how they escape from host preening. We tested whether these different microhabitat specialists were a case of repeated adaptive divergence by constructing both morphological and molecular phylogenies for a diversity of avian feather lice, including many examples of head, wing, body and generalist forms. Results Morphological and molecular based phylogenies were highly incongruent, which could be explained by rampant convergence in morphology related to microhabitat specialization on the host. In many cases lice from different microhabitat specializations, but from the same group of birds, were sister taxa. Conclusions This pattern indicates a process of repeated adaptive divergence of these parasites within host group, but convergence when comparing parasites across host groups. These results suggest that host-parasite systems might be another case in which repeated adaptive radiations could be relatively common, but potentially overlooked, because morphological convergence can obscure evolutionary relationships. PMID:22717002

Sex-Related Effects in the Superhydrophobic Properties of Damselfly Wings in Young and Old Calopteryx splendens

PubMed Central

Kuitunen, Katja; Kovalev, Alexander; Gorb, Stanislav N.

2014-01-01

Numerous sex-related morphological adaptations are connected to reproductive behavior in animals. For example, females of some insect species can submerge during oviposition, which may lead to sex-related adaptations in the hydrophobicity (water-repellency) due to specialization of certain morphological structures. On the other hand, ageing can cause changes in hydrophobicity of the surface, because the morphological structures can wear with age. Here, we investigated sex-and age-related differences in wing hydrophobicity and in morphology (spine density, wax cover characteristics, size of females' pseudopterostigma) potentially related to hydrophobicity of Calopteryx splendens damselflies. Hydrophobicity was measured with two methods, by measuring the contact angle (CA) between a wing and water droplet, and by dipping a wing into water and measuring forces needed to submerge, withdraw, and pull-out a wing from water. We found that C. splendens wings are superhydrophobic, having mean CAs of 161°. The only sex and age related difference in the hydrophobicity measurements was that young females had stronger amplitude of force fluctuations during withdrawal of wings from water than young males. This suggests that young females may form less uniform air pockets on their wings while submerged. From the morphological structures measured here, the only sex related finding was that old females had denser spine cover than young females in their wing veins. The difference may be explained by better survival of females with denser spine cover. The most important morphological character that predicted superhydrophobicity was the prevalence of long wax rods on wing veins. In addition, female pseudopterostigma area (a trait present only in females) was negatively related to pull-out force, suggesting that large pseudopterostigmas might help females to emerge from water following oviposition. The subtle sex-related differences in hydrophobicity could be explained by the fact that both sexes must resist rain, and males are occasionally in contact with water. PMID:24520406

Selection of reference genes for quantitative real-time RT-PCR assays in different morphological forms of dimorphic zygomycetous fungus Benjaminiella poitrasii.

PubMed

Pathan, Ejaj K; Ghormade, Vandana; Deshpande, Mukund V

2017-01-01

Benjaminiella poitrasii, a dimorphic non-pathogenic zygomycetous fungus, exhibits a morphological yeast (Y) to hypha (H) reversible transition in the vegetative phase, sporangiospores (S) in the asexual phase and zygospores (Z) in the sexual phase. To study the gene expression across these diverse morphological forms, suitable reference genes are required. In the present study, 13 genes viz. ACT, 18S rRNA, eEF1α, eEF-Tu,eIF-1A, Tub-α, Tub-b, Ubc, GAPDH, Try, WS-21, NADGDH and NADPGDH were evaluated for their potential as a reference, particularly for studying gene expression during the Y-H reversible transition and also for other asexual and sexual life stages of B. poitrasii. Analysis of RT-qPCR data using geNorm, normFinder and BestKeeper software revealed that genes such as Ubc, 18S rRNA and WS-21 were expressed at constant levels in each given subset of RNA samples from all the morphological phases of B. poitrasii. Therefore, these reference genes can be used to elucidate the role of morpho-genes in B. poitrasii. Further, use of the two most stably expressed genes (Ubc and WS-21) to normalize the expression of the ornithine decarboxylase gene (Bpodc) in different morphological forms of B. poitrasii, generated more reliable results, indicating that our selection of reference genes was appropriate.

Predator-induced morphological plasticity across local populations of a freshwater snail.

PubMed

Brönmark, Christer; Lakowitz, Thomas; Hollander, Johan

2011-01-01

The expression of anti-predator adaptations may vary on a spatial scale, favouring traits that are advantageous in a given predation regime. Besides, evolution of different developmental strategies depends to a large extent on the grain of the environment and may result in locally canalized adaptations or, alternatively, the evolution of phenotypic plasticity as different predation regimes may vary across habitats. We investigated the potential for predator-driven variability in shell morphology in a freshwater snail, Radix balthica, and whether found differences were a specialized ecotype adaptation or a result of phenotypic plasticity. Shell shape was quantified in snails from geographically separated pond populations with and without molluscivorous fish. Subsequently, in a common garden experiment we investigated reaction norms of snails from populations' with/without fish when exposed to chemical cues from tench (Tinca tinca), a molluscivorous fish. We found that snails from fish-free ponds had a narrow shell with a well developed spire, whereas snails that coexisted with fish had more rotund shells with a low spire, a shell morphology known to increase survival rate from shell-crushing predators. The common garden experiment mirrored the results from the field survey and showed that snails had similar reaction norms in response to chemical predator cues, i.e. the expression of shell shape was independent of population origin. Finally, we found significant differences for the trait means among populations, within each pond category (fish/fish free), suggesting a genetic component in the determination of shell morphology that has evolved independently across ponds.

Rat-strain dependent changes of dendritic and spine morphology in the hippocampus after cocaine self-administration.

PubMed

Selvas, Abraham; Coria, Santiago M; Kastanauskaite, Asta; Fernaud-Espinosa, Isabel; DeFelipe, Javier; Ambrosio, Emilio; Miguéns, Miguel

2017-01-01

We previously showed that cocaine self-administration increases spine density in CA1 hippocampal neurons in Lewis (LEW) but not in Fischer 344 (F344) rats. Dendritic spine morphology is intimately related to its function. Thus, we conducted a 3D morphological analysis of CA1 dendrites and dendritic spines in these two strains of rats. Strain-specific differences were observed prior to cocaine self-administration: LEW rats had significantly larger dendritic diameters but lower spine density than the F344 strain. After cocaine self-administration, proximal dendritic volume, dendritic surface area and spine density were increased in LEW rats, where a higher percentage of larger spines were also observed. In addition, we found a strong positive correlation between dendritic volume and spine morphology, and a moderate correlation between dendritic volume and spine density in cocaine self-administered LEW rats, an effect that was not evident in any other condition. By contrast, after cocaine self-administration, F334 rats showed decreased spine head volumes. Our findings suggest that genetic differences could play a key role in the structural plasticity induced by cocaine in CA1 pyramidal neurons. These cocaine-induced alterations could be related to differences in the memory processing of drug reward cues that could potentially explain differential individual vulnerability to cocaine addiction. © 2015 Society for the Study of Addiction.

The effect of siblings on early development: a potential contributor to personality differences in mammals.

PubMed

Hudson, Robyn; Bautista, Amando; Reyes-Meza, Verónica; Montor, Jorge Morales; Rödel, Heiko G

2011-09-01

Although most mammals grow up in the company of same or different age sibs (or half sibs), surprisingly little attention has been given to how relations among them might influence the development of individual differences in morphology, physiology, and behavior. Here we review evidence from our work on domestic and wild European rabbits, and more recently on laboratory rats, mice, and domestic cats, supporting the proposition that in mammals early sibling relations contribute to the development of individual differences in these three domains and thereby to long-term behavioral differences of the kind we might consider part of an animal's behavioral style or personality. First we report a consistent and marked negative relation between litter size and individuals' body mass at birth and weaning, as well as marked within-litter differences in prenatal body mass and placental efficiency. We then report individual differences in preweaning behaviors associated with these morphological variables such as position occupied in the litter huddle and development of motor ability, as well as physiological differences in thermoregulation, immune parameters, and endocrine indicators of stress. Finally, we report first evidence from wild rabbits that early relations among littermates may have long-term consequences for individual differences in behavioral style. We conclude that in mammals, individual differences in early growth, physiology and behavior potentially important for the development of animal personality, are shaped to an appreciable extent by early sibling relations and that this little-researched field deserves closer attention. Copyright © 2011 Wiley Periodicals, Inc.

Common evolutionary trends underlie the four-bar linkage systems of sunfish and mantis shrimp.

PubMed

Hu, Yinan; Nelson-Maney, Nathan; Anderson, Philip S L

2017-05-01

Comparative biomechanics offers an opportunity to explore the evolution of disparate biological systems that share common underlying mechanics. Four-bar linkage modeling has been applied to various biological systems such as fish jaws and crustacean appendages to explore the relationship between biomechanics and evolutionary diversification. Mechanical sensitivity states that the functional output of a mechanical system will show differential sensitivity to changes in specific morphological components. We document similar patterns of mechanical sensitivity in two disparate four-bar systems from different phyla: the opercular four-bar system in centrarchid fishes and the raptorial appendage of stomatopods. We built dynamic linkage models of 19 centrarchid and 36 stomatopod species and used phylogenetic generalized least squares regression (PGLS) to compare evolutionary shifts in linkage morphology and mechanical outputs derived from the models. In both systems, the kinematics of the four-bar mechanism show significant evolutionary correlation with the output link, while travel distance of the output arm is correlated with the coupler link. This common evolutionary pattern seen in both fish and crustacean taxa is a potential consequence of the mechanical principles underlying four-bar systems. Our results illustrate the potential influence of physical principles on morphological evolution across biological systems with different structures, behaviors, and ecologies. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

Assessing Morphological and Physiological Properties of Forest Species Using High Throughput Plant Phenotyping and Imaging Techniques

NASA Astrophysics Data System (ADS)

Mazis, A.; Hiller, J.; Morgan, P.; Awada, T.; Stoerger, V.

2017-12-01

High throughput plant phenotyping is increasingly being used to assess morphological and biophysical traits of economically important crops in agriculture. In this study, the potential application of this technique in natural resources management, through the characterization of woody plants regeneration, establishment, growth, and responses to water and nutrient manipulations was assessed. Two woody species were selected for this study, Quercus prinoides and Quercus bicolor. Seeds were collected from trees growing at the edge of their natural distribution in Nebraska and Missouri, USA. Seeds were germinated in the greenhouse and transferred to the Nebraska Innovation Campus Lemnatec3D High Throughput facility at the University of Nebraska-Lincoln. Seedlings subjected to water and N manipulations, were imaged twice or three times a week using four cameras (Visible, Fluorescence, Infrared and Hyperspectral), throughout the growing season. Traditional leaf to plant levels ecophysiological measurements were concurrently acquired to assess the relationship between these two techniques. These include gas exchange (LI 6400 and LI 6800, LICOR Inc., Lincoln NE), chlorophyll content, optical characteristics (Ocean Optics USB200), water and osmotic potentials, leaf area and weight and carbon isotope ratio. In the presentation, we highlight results on the potential use of high throughput plant phenotyping techniques to assess the morphology and physiology of woody species including responses to water availability and nutrient manipulation, and its broader application under field conditions and natural resources management. Also, we explore the different capabilities imaging provides us for modeling the plant physiological and morphological growth and how it can complement the current techniques

Morphological selection and the evaluation of potential tradeoffs between escape from predators and the climbing of waterfalls in the Hawaiian stream goby Sicyopterus stimpsoni.

PubMed

Blob, Richard W; Kawano, Sandy M; Moody, Kristine N; Bridges, William C; Maie, Takashi; Ptacek, Margaret B; Julius, Matthew L; Schoenfuss, Heiko L

2010-12-01

Environmental pressures may vary over the geographic range of a species, exposing subpopulations to divergent functional demands. How does exposure to competing demands shape the morphology of species and influence the divergence of populations? We explored these questions by performing selection experiments on juveniles of the Hawaiian goby Sicyopterus stimpsoni, an amphidromous fish that exhibits morphological differences across portions of its geographic range where different environmental pressures predominate. Juvenile S. stimpsoni face two primary and potentially opposing selective pressures on body shape as they return from the ocean to freshwater streams on islands: (1) avoiding predators in the lower reaches of a stream; and (2) climbing waterfalls to reach the habitats occupied by adults. These pressures differ in importance across the Hawaiian Islands. On the youngest island, Hawai'i, waterfalls are close to shore, thereby minimizing exposure to predators and placing a premium on climbing performance. In contrast, on the oldest major island, Kaua'i, waterfalls have eroded further inland, lengthening the exposure of juveniles to predators before migrating juveniles begin climbing. Both juvenile and adult fish show differences in body shape between these islands that would be predicted to improve evasion of predators by fish from Kaua'i (e.g., taller bodies that improve thrust) and climbing performance for fish from Hawai'i (e.g., narrower bodies that reduce drag), matching the prevailing environmental demand on each island. To evaluate how competing selection pressures and functional tradeoffs contribute to the divergence in body shape observed in S. stimpsoni, we compared selection imposed on juvenile body shape by (1) predation by the native fish Eleotris sandwicensis versus (2) climbing an artificial waterfall (∼100 body lengths). Some variables showed opposing patterns of selection that matched predictions: for example, survivors of predation had lower fineness ratios than did control fish (i.e., greater body depth for a given length), whereas successful climbers had higher fineness ratios (reducing drag) than did fish that failed. However, most morphological variables showed significant selection in only one treatment rather than opposing selection across both. Thus, functional tradeoffs between evasion of predators and minimizing drag during climbing might influence divergence in body shape across subpopulations, but even when selection is an important contributing mechanism, directly opposite patterns of selection across environmental demands are not required to generate morphological divergence.

Zein/caseinate/pectin complex nanoparticles: Formation and characterization.

PubMed

Chang, Chao; Wang, Taoran; Hu, Qiaobin; Luo, Yangchao

2017-11-01

In this study, pectin was used as coating material to form zein/caseinate/pectin complex nanoparticles through pH adjustment and heating treatment for potential oral delivery applications. The preparation conditions were studied by applying heating treatment at different pHs, either the isoelectric point of zein (pH 6.2) or caseinate (pH 4.6), or consecutively at both pHs. The particulate characteristics, including particle size, polydispersity index, and zeta potential were monitored for complex nanoparticles formed under different preparation conditions. The complex nanoparticles generally exhibited particle size smaller than 200nm with narrow distribution, spherical shape, and strong negative charge. Fourier transform infrared and fluorescence spectroscopy revealed that hydrophobic interactions and hydrogen bonds were involved in the formation of complex nanoparticles, in addition to electrostatic interactions. Fresh colloidal dispersion and freeze-dried powders varied in their morphology, depending on their preparation conditions. Our results suggested that heating pH and sequence significantly affected the morphology of complex nanoparticles, and pectin coating exerted stabilization effect under simulated gastrointestinal conditions. The present study provides insight into the formation of protein/polysaccharide complex nanoparticles under different preparation conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Mitochondrial abnormalities in Alzheimer’s disease: Possible targets for therapeutic intervention

PubMed Central

Silva, Diana F.; Selfridge, J. Eva; Lu, Jianghua; Lezi, E; Cardoso, Sandra M.; Swerdlow, Russell H.

2013-01-01

Mitochondria from persons with Alzheimer’s disease (AD) differ from those of age-matched, control subjects. Differences in mitochondrial morphology and function are well-documented, and are not brain-limited. Some of these differences are present during all stages of AD, and are even seen in individuals who are without AD symptoms and signs but who have an increased risk of developing AD. This chapter considers the status of mitochondria in AD subjects, the potential basis for AD subject mitochondrial perturbations, and the implications of these perturbations. Data from multiple lines of investigation, including epidemiologic, biochemical, molecular, and cytoplasmic hybrid studies are reviewed. The possibility that mitochondria could potentially constitute a reasonable AD therapeutic target is discussed, as are several potential mitochondrial medicine treatment strategies. PMID:22840745

Morphometric Analysis of Chemoreception Organ in Male and Female Ticks (Acari: Ixodidae).

PubMed

Josek, Tanya; Allan, Brian F; Alleyne, Marianne

2018-05-04

The Haller's organ plays a crucial role in a tick's ability to detect hosts. Even though this sensory organ is vital to tick survival, the morphology of this organ is not well understood. The objective of this study was to characterize variation in the morphological components of the Haller's organ of three medically important tick species using quantitative methods. The Haller's organs of Ixodes scapularis Say (Ixodida: Ixodidae) (black-legged tick), Amblyomma americanum (L.) (Ixodida: Ixodidae) (lone star tick), and Dermacentor variabilis (Say) (Ixodida: Ixodidae) (American dog tick) were morphologically analyzed using environmental scanning electron microscopy and geometric morphometrics, and the results were statistically interpreted using canonical variate analysis. Our data reveal significant, quantitative differences in the morphology of the Haller's organ among all three tick species and that in D. variabilis the sensory structure is sexually dimorphic. Studies like this can serve as a quantitative basis for further studies on sensor physiology, behavior, and tick species life history, potentially leading to novel methods for the prevention of tick-borne disease.

Evidence for Early Morphological Decomposition: Combining Masked Priming with Magnetoencephalography

ERIC Educational Resources Information Center

Lehtonen, Minna; Monahan, Philip J.; Poeppel, David

2011-01-01

Are words stored as morphologically structured representations? If so, when during word recognition are morphological pieces accessed? Recent masked priming studies support models that assume early decomposition of (potentially) morphologically complex words. The electrophysiological evidence, however, is inconsistent. We combined masked…

Limited Genetic Connectivity between Gorgonian Morphotypes along a Depth Gradient

PubMed Central

Gori, Andrea; Lopez-González, Pablo; Bramanti, Lorenzo; Rossi, Sergio; Gili, Josep-Maria; Abbiati, Marco

2016-01-01

Gorgonian species show a high morphological variability in relation to the environment in which they live. In coastal areas, parameters such as temperature, light, currents, and food availability vary significantly with depth, potentially affecting morphology of the colonies and the structure of the populations, as well as their connectivity patterns. In tropical seas, the existence of connectivity between shallow and deep populations supported the hypothesis that the deep coral reefs could potentially act as (reproductive) refugia fostering re-colonization of shallow areas after mortality events. Moreover, this hypothesis is not so clear accepted in temperate seas. Eunicella singularis is one of the most common gorgonian species in Northwestern Mediterranean Sea, playing an important role as ecosystem engineer by providing biomass and complexity to the coralligenous habitats. It has a wide bathymetric distribution ranging from about 10 m to 100 m. Two depth-related morphotypes have been identified, differing in colony morphology, sclerite size and shape, and occurrence of symbiotic algae, but not in mitochondrial DNA haplotypes. In the present study the genetic structure of E. singularis populations along a horizontal and bathymetric gradient was assessed using microsatellites and ITS1 sequences. Restricted gene flow was found at 30–40 m depth between the two Eunicella morphotypes. Conversely, no genetic structuring has been found among shallow water populations within a spatial scale of ten kilometers. The break in gene flow between shallow and deep populations contributes to explain the morphological variability observed at different depths. Moreover, the limited vertical connectivity hinted that the refugia hypothesis does not apply to E. singularis. Re-colonization of shallow water populations, occasionally affected by mass mortality events, should then be mainly fueled by larvae from other shallow water populations. PMID:27490900

What can we tell from particle morphology in Mesozoic charcoal assemblages?

NASA Astrophysics Data System (ADS)

Crawford, Alastair; Belcher, Claire

2015-04-01

Sedimentary charcoal particles provide a valuable record of palaeofire activity on both human and geological timescales. Charcoal is both an unambiguous indicator of wildfire, and a means of preservation of plant material in an inert form; thus it records not only the occurrence and extent of wildfire, but also the species affected. While scanning electron microscopy can be usefully employed for precise taxonomic identification of charcoals, the time and cost associated with this limit the extent to which the technique is employed. Morphometric analysis of mesocharcoal particles (c. 125-1000 µm) potentially provides a simple method for obtaining useful information from optical microscopy images. Grass fires have been shown to produce mesocharcoal particles with a higher length-to-width ratio than woodland fuel sources. In Holocene archives, aspect ratio measurements are thus used to infer the broad taxonomic affinity of the burned vegetation. Since Mesozoic charcoals display similarly heterogeneous morphologies, we investigate whether there is a similar potential to infer the broad botanical affinities of Mesozoic charcoal assemblages from simple morphological metrics. We have used image analysis to analyse a range of Jurassic and Cretaceous sedimentary rocks representing different vegetation communities and depositional environments, and also to determine the range of charcoal particle morphologies which can be produced from different modern taxa under laboratory conditions. We find that modern charcoals break down into mesocharcoal particles of very variable aspect ratio, and this appears to be dependent on taxonomic position. Our analysis of fragmented laboratory-produced charcoals indicates that pteridophytes produce much more elongate particles than either conifers or non-grass angiosperms. We suggest that for charcoal assemblages that predate the evolution of grasses, high average aspect ratios may be a useful indicator of the burning of a pteridophyte-dominated flora.

Global morphological analysis of marine viruses shows minimal regional variation and dominance of non-tailed viruses

PubMed Central

Brum, Jennifer R; Schenck, Ryan O; Sullivan, Matthew B

2013-01-01

Viruses influence oceanic ecosystems by causing mortality of microorganisms, altering nutrient and organic matter flux via lysis and auxiliary metabolic gene expression and changing the trajectory of microbial evolution through horizontal gene transfer. Limited host range and differing genetic potential of individual virus types mean that investigations into the types of viruses that exist in the ocean and their spatial distribution throughout the world's oceans are critical to understanding the global impacts of marine viruses. Here we evaluate viral morphological characteristics (morphotype, capsid diameter and tail length) using a quantitative transmission electron microscopy (qTEM) method across six of the world's oceans and seas sampled through the Tara Oceans Expedition. Extensive experimental validation of the qTEM method shows that neither sample preservation nor preparation significantly alters natural viral morphological characteristics. The global sampling analysis demonstrated that morphological characteristics did not vary consistently with depth (surface versus deep chlorophyll maximum waters) or oceanic region. Instead, temperature, salinity and oxygen concentration, but not chlorophyll a concentration, were more explanatory in evaluating differences in viral assemblage morphological characteristics. Surprisingly, given that the majority of cultivated bacterial viruses are tailed, non-tailed viruses appear to numerically dominate the upper oceans as they comprised 51–92% of the viral particles observed. Together, these results document global marine viral morphological characteristics, show that their minimal variability is more explained by environmental conditions than geography and suggest that non-tailed viruses might represent the most ecologically important targets for future research. PMID:23635867

Antimicrobial and Antiproliferative Potential of Anadenanthera colubrina (Vell.) Brenan

PubMed Central

Lima, Rennaly de Freitas; Alves, Érika Ponchet; Rosalen, Pedro Luiz; Ruiz, Ana Lúcia Tasca Gois; Teixeira Duarte, Marta Cristina; Góes, Vivian Fernandes Furletti; de Medeiros, Ana Cláudia Dantas; Pereira, Jozinete Vieira; Godoy, Gustavo Pina; Melo de Brito Costa, Edja Maria

2014-01-01

The aim of the present study was to perform an in vitro analysis of the antimicrobial and antiproliferative potential of an extract from Anadenanthera colubrina (Vell.) Brenan (angico) and chemically characterize the crude extract. Antimicrobial action was evaluated based on the minimum inhibitory concentration (MIC), minimum bactericidal/fungicidal concentration, and the inhibition of formation to oral biofilm. Cell morphology was determined through scanning electron microscopy (SEM). Six strains of tumor cells were used for the determination of antiproliferative potential. The extract demonstrated strong antifungal activity against Candida albicans ATCC 18804 (MIC = 0.031 mg/mL), with similar activity found regarding the ethyl acetate fraction. The extract and active fraction also demonstrated the capacity to inhibit the formation of Candida albicans to oral biofilm after 48 hours, with median values equal to or greater than the control group, but the difference did not achieve statistical significance (P > 0.05). SEM revealed alterations in the cell morphology of the yeast. Regarding antiproliferative activity, the extract demonstrated cytostatic potential in all strains tested. The present findings suggest strong antifungal potential for Anadenanthera colubrina (Vell.) Brenan as well as a tendency toward diminishing the growth of human tumor cells. PMID:25093029

Facile electrocatalytic redox of hemoglobin by flower-like gold nanoparticles on boron-doped diamond surface.

PubMed

Li, Mingfang; Zhao, Guohua; Geng, Rong; Hu, Huikang

2008-11-01

The flower-like gold nanoparticles together with spherical and convex polyhedron gold nanoparticles were fabricated on boron-doped diamond (BDD) surface by one-step and simple electrochemical method through easily controlling the applied potential and the concentration of HAuCl(4). The recorded X-ray diffraction (XRD) patterns confirmed that these three shapes of gold nanoparticles were dominated by different crystal facets. The cyclic voltammetric results indicated that the morphology of gold nanoparticles plays big role in their electrochemical behaviors. The direct electrochemistry of hemoglobin (Hb) was realized on all the three different shapes of nanogold-attached BDD surface without the aid of any electron mediator. In pH 4.5 acetate buffer solutions (ABS), Hb showed a pair of well defined and quasi-reversible redox peaks. However, the results obtained demonstrated that the redox peak potential, the average surface concentration of electroactive heme, and the electron transfer rates of Hb are greatly dependent upon the surface morphology of gold nanoparticles. The electron transfer rate constant of hemoglobin over flower-like nanogold/BDD electrode was more than two times higher than that over spherical and convex polyhedron nanogold. The observed differences may be ascribed to the difference in gold particle characteristics including surface roughness, exposed surface area, and crystal structure.

Identification of potential rockfall source areas at a regional scale using a DEM-based geomorphometric analysis

NASA Astrophysics Data System (ADS)

Loye, A.; Jaboyedoff, M.; Pedrazzini, A.

2009-10-01

The availability of high resolution Digital Elevation Models (DEM) at a regional scale enables the analysis of topography with high levels of detail. Hence, a DEM-based geomorphometric approach becomes more accurate for detecting potential rockfall sources. Potential rockfall source areas are identified according to the slope angle distribution deduced from high resolution DEM crossed with other information extracted from geological and topographic maps in GIS format. The slope angle distribution can be decomposed in several Gaussian distributions that can be considered as characteristic of morphological units: rock cliffs, steep slopes, footslopes and plains. A terrain is considered as potential rockfall sources when their slope angles lie over an angle threshold, which is defined where the Gaussian distribution of the morphological unit "Rock cliffs" become dominant over the one of "Steep slopes". In addition to this analysis, the cliff outcrops indicated by the topographic maps were added. They contain however "flat areas", so that only the slope angles values above the mode of the Gaussian distribution of the morphological unit "Steep slopes" were considered. An application of this method is presented over the entire Canton of Vaud (3200 km2), Switzerland. The results were compared with rockfall sources observed on the field and orthophotos analysis in order to validate the method. Finally, the influence of the cell size of the DEM is inspected by applying the methodology over six different DEM resolutions.

Fabrication of low reflective nanopore-type black Si layer using one-step Ni-assisted chemical etching for Si solar cell application

NASA Astrophysics Data System (ADS)

Takaloo, AshkanVakilipour; Kolahdouz, Mohammadreza; Poursafar, Jafar; Es, Firat; Turan, Rasit; Ki-Joo, Seung

2018-03-01

Nanotextured Si fabricated through metal-assisted chemical etching (MACE) technique exhibits a promising potential for producing antireflective layer for photovoltaic (PV) application. In this study, a novel single-step nickel (Ni) assisted etching technique was applied to produce an antireflective, nonporous Si (black Si) in an aqueous solution containing hydrofluoric acid (HF), hydrogen peroxide (H2O2) and NiSO4 at 40 °C. Field emission scanning electron microscope was used to characterize different morphologies of the textured Si. Optical reflection measurements of samples were carried out to compare the reflectivity of different morphologies. Results indicated that vertical as well as horizontal pores with nanosized diameters were bored in the Si wafer after 1 h treatment in the etching solution containing different molar ratios of H2O2 to HF. Increasing H2O2 concentration in electrochemical etching solution had a considerable influence on the morphology due to higher injection of positive charges from Ni atoms onto the Si surface. Optimized concentration of H2O2 led to formation of an antireflective layer with 2.1% reflectance of incident light.

Jack-of-all-trades master of all? Snake vertebrae have a generalist inner organization

NASA Astrophysics Data System (ADS)

Houssaye, Alexandra; Boistel, Renaud; Böhme, Wolfgang; Herrel, Anthony

2013-11-01

Snakes are a very speciose group of squamates that adapted to various habitats and ecological niches. Their ecological diversity is of particular interest and functional demands associated with their various styles of locomotion are expected to result in anatomical specializations. In order to explore the potential adaptation of snakes to their environment we here analyze variation in vertebral structure at the microanatomical level in species with different locomotor adaptations. Vertebrae, being a major element of the snake body, are expected to display adaptations to the physical constraints associated with the different locomotor modes and environments. Our results revealed a rather homogenous vertebral microanatomy in contrast to what has been observed for other squamates and amniotes more generally. We here suggest that the near-absence of microanatomical specializations in snake vertebrae might be correlated to their rather homogeneous overall morphology and reduced range of morphological diversity, as compared to lizards. Thus, snakes appear to retain a generalist inner morphology that allows them to move efficiently in different environments. Only a few ecologically highly specialized taxa appear to display some microanatomical specializations that remain to be studied in greater detail.

The tooth, the whole tooth and nothing but the tooth: tooth shape and ontogenetic shift dynamics in the white shark Carcharodon carcharias.

PubMed

French, G C A; Stürup, M; Rizzuto, S; van Wyk, J H; Edwards, D; Dolan, R W; Wintner, S P; Towner, A V; Hughes, W O H

2017-10-01

Results from this study of the white shark Carcharodon carcharias include measurements obtained using a novel photographic method that reveal significant differences between the sexes in the relationship between tooth cuspidity and shark total length, and a novel ontogenetic change in male tooth shape. Males exhibit broader upper first teeth and increased distal inclination of upper third teeth with increasing length, while females do not present a consistent morphological change. Substantial individual variation, with implications for pace of life syndrome, was present in males and tooth polymorphism was suggested in females. Sexual differences and individual variation may play major roles in ontogenetic changes in tooth morphology in C. carcharias, with potential implications for their foraging biology. Such individual and sexual differences should be included in studies of ontogenetic shift dynamics in other species and systems. © 2017 The Fisheries Society of the British Isles.

From coffee ring to spherulites ring of poly(ethylene oxide) film from drying droplet

NASA Astrophysics Data System (ADS)

Hu, Yinchun; Zhang, Xuerong; Qiu, Maibo; Wei, Yan; Zhou, Qiong; Huang, Di

2018-03-01

We discuss how the "spherulites ring" morphology and "coffee ring" profile of PEO film formed by the drying droplet at glass substrate with different heating rate. Upon increasing the heating rate of substrate, it is found that deposited PEO film from drying droplet shows the unusually observed "coffee ring" profile and "spherulites ring" morphology. The main mechanism for this phenomenon is proposed to be an enhanced Marangoni convection which is induced by the increased solute concentration gradient and reduced viscous force above 70 °C. A simple formation mechanism of the unusually observed "coffee ring" profile and "spherulites ring" morphology is proposed. These findings can be exploited to trace the center of Marangoni convection, with potential applications in designing the spherulite patterns of crystalline polymer films in ink-jet printing and self-assembly fields.

Forecasting longitudinal changes in oropharyngeal tumor morphology throughout the course of head and neck radiation therapy

PubMed Central

Yock, Adam D.; Rao, Arvind; Dong, Lei; Beadle, Beth M.; Garden, Adam S.; Kudchadker, Rajat J.; Court, Laurence E.

2014-01-01

Purpose: To create models that forecast longitudinal trends in changing tumor morphology and to evaluate and compare their predictive potential throughout the course of radiation therapy. Methods: Two morphology feature vectors were used to describe 35 gross tumor volumes (GTVs) throughout the course of intensity-modulated radiation therapy for oropharyngeal tumors. The feature vectors comprised the coordinates of the GTV centroids and a description of GTV shape using either interlandmark distances or a spherical harmonic decomposition of these distances. The change in the morphology feature vector observed at 33 time points throughout the course of treatment was described using static, linear, and mean models. Models were adjusted at 0, 1, 2, 3, or 5 different time points (adjustment points) to improve prediction accuracy. The potential of these models to forecast GTV morphology was evaluated using leave-one-out cross-validation, and the accuracy of the models was compared using Wilcoxon signed-rank tests. Results: Adding a single adjustment point to the static model without any adjustment points decreased the median error in forecasting the position of GTV surface landmarks by the largest amount (1.2 mm). Additional adjustment points further decreased the forecast error by about 0.4 mm each. Selection of the linear model decreased the forecast error for both the distance-based and spherical harmonic morphology descriptors (0.2 mm), while the mean model decreased the forecast error for the distance-based descriptor only (0.2 mm). The magnitude and statistical significance of these improvements decreased with each additional adjustment point, and the effect from model selection was not as large as that from adding the initial points. Conclusions: The authors present models that anticipate longitudinal changes in tumor morphology using various models and model adjustment schemes. The accuracy of these models depended on their form, and the utility of these models includes the characterization of patient-specific response with implications for treatment management and research study design. PMID:25086518

Forecasting longitudinal changes in oropharyngeal tumor morphology throughout the course of head and neck radiation therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yock, Adam D.; Kudchadker, Rajat J.; Rao, Arvind

2014-08-15

Purpose: To create models that forecast longitudinal trends in changing tumor morphology and to evaluate and compare their predictive potential throughout the course of radiation therapy. Methods: Two morphology feature vectors were used to describe 35 gross tumor volumes (GTVs) throughout the course of intensity-modulated radiation therapy for oropharyngeal tumors. The feature vectors comprised the coordinates of the GTV centroids and a description of GTV shape using either interlandmark distances or a spherical harmonic decomposition of these distances. The change in the morphology feature vector observed at 33 time points throughout the course of treatment was described using static, linear,more » and mean models. Models were adjusted at 0, 1, 2, 3, or 5 different time points (adjustment points) to improve prediction accuracy. The potential of these models to forecast GTV morphology was evaluated using leave-one-out cross-validation, and the accuracy of the models was compared using Wilcoxon signed-rank tests. Results: Adding a single adjustment point to the static model without any adjustment points decreased the median error in forecasting the position of GTV surface landmarks by the largest amount (1.2 mm). Additional adjustment points further decreased the forecast error by about 0.4 mm each. Selection of the linear model decreased the forecast error for both the distance-based and spherical harmonic morphology descriptors (0.2 mm), while the mean model decreased the forecast error for the distance-based descriptor only (0.2 mm). The magnitude and statistical significance of these improvements decreased with each additional adjustment point, and the effect from model selection was not as large as that from adding the initial points. Conclusions: The authors present models that anticipate longitudinal changes in tumor morphology using various models and model adjustment schemes. The accuracy of these models depended on their form, and the utility of these models includes the characterization of patient-specific response with implications for treatment management and research study design.« less

An optimal transportation approach for nuclear structure-based pathology.

PubMed

Wang, Wei; Ozolek, John A; Slepčev, Dejan; Lee, Ann B; Chen, Cheng; Rohde, Gustavo K

2011-03-01

Nuclear morphology and structure as visualized from histopathology microscopy images can yield important diagnostic clues in some benign and malignant tissue lesions. Precise quantitative information about nuclear structure and morphology, however, is currently not available for many diagnostic challenges. This is due, in part, to the lack of methods to quantify these differences from image data. We describe a method to characterize and contrast the distribution of nuclear structure in different tissue classes (normal, benign, cancer, etc.). The approach is based on quantifying chromatin morphology in different groups of cells using the optimal transportation (Kantorovich-Wasserstein) metric in combination with the Fisher discriminant analysis and multidimensional scaling techniques. We show that the optimal transportation metric is able to measure relevant biological information as it enables automatic determination of the class (e.g., normal versus cancer) of a set of nuclei. We show that the classification accuracies obtained using this metric are, on average, as good or better than those obtained utilizing a set of previously described numerical features. We apply our methods to two diagnostic challenges for surgical pathology: one in the liver and one in the thyroid. Results automatically computed using this technique show potentially biologically relevant differences in nuclear structure in liver and thyroid cancers.

An optimal transportation approach for nuclear structure-based pathology

PubMed Central

Wang, Wei; Ozolek, John A.; Slepčev, Dejan; Lee, Ann B.; Chen, Cheng; Rohde, Gustavo K.

2012-01-01

Nuclear morphology and structure as visualized from histopathology microscopy images can yield important diagnostic clues in some benign and malignant tissue lesions. Precise quantitative information about nuclear structure and morphology, however, is currently not available for many diagnostic challenges. This is due, in part, to the lack of methods to quantify these differences from image data. We describe a method to characterize and contrast the distribution of nuclear structure in different tissue classes (normal, benign, cancer, etc.). The approach is based on quantifying chromatin morphology in different groups of cells using the optimal transportation (Kantorovich-Wasserstein) metric in combination with the Fisher discriminant analysis and multidimensional scaling techniques. We show that the optimal transportation metric is able to measure relevant biological information as it enables automatic determination of the class (e.g. normal vs. cancer) of a set of nuclei. We show that the classification accuracies obtained using this metric are, on average, as good or better than those obtained utilizing a set of previously described numerical features. We apply our methods to two diagnostic challenges for surgical pathology: one in the liver and one in the thyroid. Results automatically computed using this technique show potentially biologically relevant differences in nuclear structure in liver and thyroid cancers. PMID:20977984

Plastic degradation by thermophilic Bacillus sp. BCBT21 isolated from composting agricultural residual in Vietnam

NASA Astrophysics Data System (ADS)

Dang, Thi Cam Ha; Thang Nguyen, Dang; Thai, Hoang; Chinh Nguyen, Thuy; Thu Hien Tran, Thi; Le, Viet Hung; Huynh Nguyen, Van; Bach Tran, Xuan; Phuong Thao Pham, Thi; Giang Nguyen, Truong; Nguyen, Quang Trung

2018-03-01

Three different kinds of plastic bags HL, VHL, and VN1 with different chemical nature were degraded by a novel thermophilic bacterial strain isolated from composting agricultural residual in Vietnam in shaking liquid medium at 55 °C after 30 d. The new strain was classified in the Bacillus genus by morphological property and sequence of partial 16Sr RNA coding gene and named as Bacillus sp. BCBT21. This strain could produce extracellular hydrolase enzymes including lipase, CMCase, xylanase, chitinase, and protease with different level of activity in the same media. After a 30-d treatment at 55 °C with Bacillus sp. BCBT21, all characteristics including properties and morphology of treated plastic bags had been significantly changed. The weight loss, structure and surface morphology of these bags as well as the change in the average molecular weight of VHL bag were detected. Especially, the average molecular weight of VHL bag was significantly reduced from 205 000 to 116 760. New metabolites from the treated bags indicated biodegradation occurring with the different pathways. This finding suggests that there is high potential to develop an effective integrated method for plastic bags degradation by a combination of extracellular enzymes from bacteria and fungi existing in the composting process.

Pollinator-mediated selection on floral morphology: evidence for transgressive evolution in a derived hybrid lineage.

PubMed

Anton, K A; Ward, J R; Cruzan, M B

2013-03-01

Hybridization between closely related lineages is a mechanism that might promote substantive changes in phenotypic traits of descendants, resulting in transgressive evolution. Interbreeding between divergent but morphologically similar lineages can produce exceptional phenotypes, but the potential for transgressive variation to facilitate long-term trait changes in derived hybrid lineages has received little attention. We compare pollinator-mediated selection on transgressive floral traits in both early-generation and derived hybrid lineages of the Piriqueta cistoides ssp. caroliniana complex. The bowl-shaped flowers of morphotypes in this complex have similar gross morphologies and attract a common suite of small insect pollinators. However, they are defined by significant differences in characters that generate pollinator interest and visitation, including floral area and petal separation. In common garden experiments, patterns of pollen deposition in early-generation recombinant hybrids indicate that Piriqueta's pollinators favour flowers with greater area and reduced petal separation. Changes in floral morphology in derived hybrid lineages are consistent with predictions from selection gradients, but the magnitude of change is limited relative to the range of transgressive variation. These results suggest that hybridization provides variation for evolution of divergent floral traits. However, the potential for extreme transgressive variants to contribute to phenotypic shifts may be limited due to reduced heritability, evolutionary constraints or fitness trade-offs. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

Hyperspectral Imaging, Flow cytometry and Microscopic Morphology of Silver Nanoparticle within Cells

EPA Science Inventory

The ability to detect and track silver nanoparticles (AgNP) that enter cells is important to understand the potential biological and toxicological actions of AgNP. The uptake and fate in cells of four different types of AgNP was studied in a retinal pigment epithelial cell line ...

Comparative “omics” of the Fusarium fujikuroi species complex highlights differences in genetic potential and metabolite synthesis

USDA-ARS?s Scientific Manuscript database

Species of the Fusarium fujikuroi species complex (FFC) cause a wide spectrum of often devastating diseases on diverse agricultural crops, including coffee, fig, mango, maize, rice, and sugarcane. Although species within the FFC are difficult to distinguish by morphology, and their genes often share...

Characteristics of Non-Cohesive Embankment Failure

NASA Astrophysics Data System (ADS)

Yusof, Z. M.; Wahab, A. K. A.; Ismail, Z.; Amerudin, S.

2018-04-01

Embankments are important infrastructure built to provide flood control. They also present risks to property and life due to their potential to fail and cause catastrophic flooding. To mitigate these risks, authorities and regulators need to carefully analyse and inspect dams to identify potential failure modes and protect against them. This paper presents morphology of an embankment study and its sediment behaviour of different grain sizes after the embankment fails. A few experiments were carried out for the embankment size of 1V:3H with different sediment grain sizes; medium and coarser sand. The embankment material used is non-cohesive soil with the embankment height of 0.1 m. The embankment is tested with inflows rate of Q = 0.8 L/s. Experimental results showed the peak discharge for the same inflow rate is affected by the shape of embankment breached. The peak discharge of medium grain size of the embankment is highest, which gave 3.63 L/s in comparison with a coarser embankment. This concludes that the embankment morphology patterns are dissimilar to each other. The flow and dimension of embankment are shown to influence the characteristics of embankment failure.

Electron Transfer Strategies Regulate Carbonate Mineral and Micropore Formation

NASA Astrophysics Data System (ADS)

Zeng, Zhirui; Tice, Michael M.

2018-01-01

Some microbial carbonates are robust biosignatures due to their distinct morphologies and compositions. However, whether carbonates induced by microbial iron reduction have such features is unknown. Iron-reducing bacteria use various strategies to transfer electrons to iron oxide minerals (e.g., membrane-bound enzymes, soluble electron shuttles, nanowires, as well as different mechanisms for moving over or attaching to mineral surfaces). This diversity has the potential to create mineral biosignatures through manipulating the microenvironments in which carbonate precipitation occurs. We used Shewanella oneidensis MR-1, Geothrix fermentans, and Geobacter metallireducens GS-15, representing three different strategies, to reduce solid ferric hydroxide in order to evaluate their influence on carbonate and micropore formation (micro-size porosity in mineral rocks). Our results indicate that electron transfer strategies determined the morphology (rhombohedral, spherical, or long-chained) of precipitated calcium-rich siderite by controlling the level of carbonate saturation and the location of carbonate formation. Remarkably, electron transfer strategies also produced distinctive cell-shaped micropores in both carbonate and hydroxide minerals, thus producing suites of features that could potentially serve as biosignatures recording information about the sizes, shapes, and physiologies of iron-reducing organisms.

Seed-Mediated Growth of Gold Nanocrystals: Changes to the Crystallinity or Morphology as Induced by the Treatment of Seeds with a Sulfur Species

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Yiqun; Luo, Ming; Tao, Jing

We report our observation of changes to the crystallinity or morphology during seed-mediated growth of Au nanocrystals. When single-crystal Au seeds with a spherical or rod-like shape were treated with a chemical species such as S₂O₃²⁻ ions, twin defects were developed during the growth process to generate multiply twinned nanostructures. X-ray photoelectron spectroscopy analysis indicated that the S₂O₃²⁻ ions were chemisorbed on the surfaces of the seeds during the treatment. The chemisorbed S₂O₃²⁻ ions somehow influenced the crystallization of Au atoms added onto the surface during a growth process, leading to the formation of twin defects. In contrast to themore » spherical and rod-like Au seeds, the single-crystal structure was retained to generate a concave morphology when single-crystal Au seeds with a cubic or octahedral shape were used for a similar treatment and then seed-mediated growth. The different outcomes are likely related to the difference in spatial distribution of S₂O₃²⁻ ions chemisorbed on the surface of a seed. This approach based on surface modification is potentially extendable to other noble metals for engineering the crystallinity and morphology of nanocrystals formed via seed-mediated growth.« less

Seed-Mediated Growth of Gold Nanocrystals: Changes to the Crystallinity or Morphology as Induced by the Treatment of Seeds with a Sulfur Species

DOE PAGES

Zheng, Yiqun; Luo, Ming; Tao, Jing; ...

2014-12-11

We report our observation of changes to the crystallinity or morphology during seed-mediated growth of Au nanocrystals. When single-crystal Au seeds with a spherical or rod-like shape were treated with a chemical species such as S₂O₃²⁻ ions, twin defects were developed during the growth process to generate multiply twinned nanostructures. X-ray photoelectron spectroscopy analysis indicated that the S₂O₃²⁻ ions were chemisorbed on the surfaces of the seeds during the treatment. The chemisorbed S₂O₃²⁻ ions somehow influenced the crystallization of Au atoms added onto the surface during a growth process, leading to the formation of twin defects. In contrast to themore » spherical and rod-like Au seeds, the single-crystal structure was retained to generate a concave morphology when single-crystal Au seeds with a cubic or octahedral shape were used for a similar treatment and then seed-mediated growth. The different outcomes are likely related to the difference in spatial distribution of S₂O₃²⁻ ions chemisorbed on the surface of a seed. This approach based on surface modification is potentially extendable to other noble metals for engineering the crystallinity and morphology of nanocrystals formed via seed-mediated growth.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Xiaomei; Lv, Xin; Wang, Limin

Graphical abstract: - Highlights: • Effect of CTAB on the morphology and crystallization of MnFe{sub 2}O{sub 4}. • The lowest coercivity of MnFe{sub 2}O{sub 4} polyhedron is 11.9 Oe. • MnFe{sub 2}O{sub 4} as anode for LIB shows good reversible capacity and cycle performances. - Abstract: The uniform different morphologies MnFe{sub 2}O{sub 4}, including cube, truncated cube, polyhedron and octahedron, were successfully synthesized via a solvothermal route using cetyltrimethylammonium bromide. The results of control experiments revealed that the concentration of cetyltrimethylammonium bromide was an important factor, which affected the morphology and crystallization of MnFe{sub 2}O{sub 4} submicro-crystals. All the preparedmore » samples exhibited soft-magnetic behavior at room temperature. Especially, the coercivity of MnFe{sub 2}O{sub 4} polyhedron with 200 nm diameter was 11.9 Oe, which was among the lowest values reported so far. Moreover, MnFe{sub 2}O{sub 4} submicro-crystals with special morphologies demonstrated higher reversible capacity (about 1000 mAh g{sup −1}) and different cycle performances. After 50 cycles, polyhedron structure remained 428 mAh/g. The MnFe{sub 2}O{sub 4} would have a potential application as anode material for lithium ion batteries.« less

Nanoscale Roughness and Morphology Affect the IsoElectric Point of Titania Surfaces

PubMed Central

Borghi, Francesca; Vyas, Varun; Podestà, Alessandro; Milani, Paolo

2013-01-01

We report on the systematic investigation of the role of surface nanoscale roughness and morphology on the charging behaviour of nanostructured titania (TiO2) surfaces in aqueous solutions. IsoElectric Points (IEPs) of surfaces have been characterized by direct measurement of the electrostatic double layer interactions between titania surfaces and the micrometer-sized spherical silica probe of an atomic force microscope in NaCl aqueous electrolyte. The use of a colloidal probe provides well-defined interaction geometry and allows effectively probing the overall effect of nanoscale morphology. By using supersonic cluster beam deposition to fabricate nanostructured titania films, we achieved a quantitative control over the surface morphological parameters. We performed a systematical exploration of the electrical double layer properties in different interaction regimes characterized by different ratios of characteristic nanometric lengths of the system: the surface rms roughness Rq, the correlation length ξ and the Debye length λD. We observed a remarkable reduction by several pH units of IEP on rough nanostructured surfaces, with respect to flat crystalline rutile TiO2. In order to explain the observed behavior of IEP, we consider the roughness-induced self-overlap of the electrical double layers as a potential source of deviation from the trend expected for flat surfaces. PMID:23874708

Decreasing pelvic incidence is associated with greater risk of cam morphology

PubMed Central

Fowers, C. A.; Yuh, R. T.; Gebhart, J. J.; Salata, M. J.; Liu, R. W.

2016-01-01

Objectives The spinopelvic relationship (including pelvic incidence) has been shown to influence pelvic orientation, but its potential association with femoroacetabular impingement has not been thoroughly explored. The purpose of this study was to prove the hypothesis that decreasing pelvic incidence is associated with increased risk of cam morphology. Methods Two matching cohorts were created from a collection of cadaveric specimens with known pelvic incidences: 50 subjects with the highest pelvic incidence (all subjects > 60°) and 50 subjects with the lowest pelvic incidence (all subjects < 35°). Femoral version, acetabular version, and alpha angles were directly measured from each specimen bilaterally. Cam morphology was defined as alpha angle > 55°. Differences between the two cohorts were analysed with a Student’s t-test and the difference in incidence of cam morphology was assessed using a chi-squared test. The significance level for all tests was set at p < 0.05. Results Cam morphology was identified in 47/100 (47%) femurs in the cohort with pelvic incidence < 35° and in only 25/100 (25%) femurs in the cohort with pelvic incidence > 60° (p = 0.002). The mean alpha angle was also greater in the cohort with pelvic incidence < 35° (mean 53.7°, sd 10.7° versus mean 49.7°, sd 10.6°; p = 0.008). Conclusions Decreased pelvic incidence is associated with development of cam morphology. We propose a novel theory wherein subjects with decreased pelvic incidence compensate during gait (to maintain optimal sagittal balance) through anterior pelvic tilt, creating artificial anterior acetabular overcoverage and recurrent impingement that increases risk for cam morphology. Cite this article: W. Z. Morris, C. A. Fowers, R. T. Yuh, J. J. Gebhart, M. J. Salata, R. W. Liu. Decreasing pelvic incidence is associated with greater risk of cam morphology. Bone Joint Res 2016;5:387–392. DOI: 10.1302/2046-3758.59.BJR-2016-0028.R1. PMID:27650107

Genetic and morphological contrasts between wild and anthropogenic populations of Agave parryi var. huachucensis in south-eastern Arizona.

PubMed

Parker, Kathleen C; Trapnell, Dorset W; Hamrick, J L; Hodgson, Wendy C

2014-05-01

At least seven species of Agave, including A. parryi, were cultivated prehistorically in Arizona, serving as important sources of food and fibre. Many relict populations from ancient cultivation remain in the modern landscape, offering a unique opportunity to study pre-Columbian plant manipulation practices. This study examined genetic and morphological variation in six A. p. var. huachucensis populations of unknown origin to compare them with previous work on A. parryi populations of known origin, to infer their cultivation history and to determine whether artificial selection is evident in populations potentially managed by early agriculturalists. Six A. p. var. huachucensis and 17 A. parryi populations were sampled, and morphometric, allozyme and microsatellite data were used to compare morphology and genetic structure in purportedly anthropogenic and wild populations, as well as in the two taxa. Analysis of molecular variance and Bayesian clustering were performed to partition variation associated with taxonomic identity and hypothesized evolutionary history, to highlight patterns of similarity among populations and to identify potential wild sources for the planting stock. A p. var. huachucensis and A. parryi populations differed significantly both morphologically and genetically. Like A. parryi, wild A. p. var. huachucensis populations were more genetically diverse than the inferred anthropogenic populations, with greater expected heterozygosity, percentage of polymorphic loci and number of alleles. Inferred anthropogenic populations exhibited many traits indicative of past active cultivation: greater morphological uniformity, fixed heterozygosity for several loci (non-existent in wild populations), fewer multilocus genotypes and strong differentiation among populations. Where archaeological information is lacking, the genetic signature of many Agave populations in Arizona can be used to infer their evolutionary history and to identify potentially fruitful sites for archaeological investigation of ancient settlements and cultivation practices. The same approach can clearly be adopted for other species in similar situations.

Genetic and morphological contrasts between wild and anthropogenic populations of Agave parryi var. huachucensis in south-eastern Arizona

PubMed Central

Parker, Kathleen C.; Trapnell, Dorset W.; Hamrick, J. L.; Hodgson, Wendy C.

2014-01-01

Background and Aims At least seven species of Agave, including A. parryi, were cultivated prehistorically in Arizona, serving as important sources of food and fibre. Many relict populations from ancient cultivation remain in the modern landscape, offering a unique opportunity to study pre-Columbian plant manipulation practices. This study examined genetic and morphological variation in six A. p. var. huachucensis populations of unknown origin to compare them with previous work on A. parryi populations of known origin, to infer their cultivation history and to determine whether artificial selection is evident in populations potentially managed by early agriculturalists. Methods Six A. p. var. huachucensis and 17 A. parryi populations were sampled, and morphometric, allozyme and microsatellite data were used to compare morphology and genetic structure in purportedly anthropogenic and wild populations, as well as in the two taxa. Analysis of molecular variance and Bayesian clustering were performed to partition variation associated with taxonomic identity and hypothesized evolutionary history, to highlight patterns of similarity among populations and to identify potential wild sources for the planting stock. Key Results A p. var. huachucensis and A. parryi populations differed significantly both morphologically and genetically. Like A. parryi, wild A. p. var. huachucensis populations were more genetically diverse than the inferred anthropogenic populations, with greater expected heterozygosity, percentage of polymorphic loci and number of alleles. Inferred anthropogenic populations exhibited many traits indicative of past active cultivation: greater morphological uniformity, fixed heterozygosity for several loci (non-existent in wild populations), fewer multilocus genotypes and strong differentiation among populations. Conclusions Where archaeological information is lacking, the genetic signature of many Agave populations in Arizona can be used to infer their evolutionary history and to identify potentially fruitful sites for archaeological investigation of ancient settlements and cultivation practices. The same approach can clearly be adopted for other species in similar situations. PMID:24638822

Resurrection of Bronchocela burmana Blanford, 1878 for the Green Crested Lizard (Squamata, Agamidae) of southern Myanmar

PubMed Central

Zug, George R.; Mulcahy, Daniel G.; Vindum, Jens V.

2017-01-01

Abstract Recent fieldwork in southern Tanintharyi revealed the presence of a small Green Crested Lizard in the wet evergreen forest. We generated mtDNA sequence data (ND2) that demonstrates that this population’s nearest relative is Bronchocela rayaensis Grismer et al., 2015 of Pulau Langkawi, northwestern Peninsular Malaysia and Phuket Island. Morphologically the Burmese Bronchocela shares many features with Bronchocela rayaensis, which potentially would make this recently described Thai-Malay species a synonym of Bronchocela burmana Blanford, 1878; however, we interpret the genetic and morphological differences to reflect evolutionary divergence and recommend the recognition of both species. PMID:28331413

Resurrection of Bronchocela burmana Blanford, 1878 for the Green Crested Lizard (Squamata, Agamidae) of southern Myanmar.

PubMed

Zug, George R; Mulcahy, Daniel G; Vindum, Jens V

2017-01-01

Recent fieldwork in southern Tanintharyi revealed the presence of a small Green Crested Lizard in the wet evergreen forest. We generated mtDNA sequence data (ND2) that demonstrates that this population's nearest relative is Bronchocela rayaensis Grismer et al., 2015 of Pulau Langkawi, northwestern Peninsular Malaysia and Phuket Island. Morphologically the Burmese Bronchocela shares many features with Bronchocela rayaensis , which potentially would make this recently described Thai-Malay species a synonym of Bronchocela burmana Blanford, 1878; however, we interpret the genetic and morphological differences to reflect evolutionary divergence and recommend the recognition of both species.

Preparation, thermal property and morphology analysis of waterborne polyurethane-acrylate

NASA Astrophysics Data System (ADS)

Zhao, Zhenyu; Jing, Zefeng; Qiu, Fengxian; Dai, Yuting; Xu, Jicheng; Yu, Zongping; Yang, Pengfei

2017-01-01

A series of waterborne polyurethane-acrylate (WPUA) dispersions were prepared with isophorone diisocyanate (IPDI), polyether polyol (NJ-210), dimethylol propionic acid (DMPA), hydroxyethyl methyl acrylate (HEMA), different proportions of methyl methacrylate (MMA) and ethyl acrylate (MMA and EA) and initiating agent by the emulsion co-polymerization. The structures, thermal properties and morphology of WPUA films were characterized with FT-IR, DSC, SEM and AFM. Performances of the dispersions and films were studied by means of apparent viscidity, particle size and polydispersity, surface tension and mechanical properties. The obtained WPUA have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes.

Influence of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) on zinc electrodeposition

NASA Astrophysics Data System (ADS)

Lehr, I. L.; Saidman, S. B.

2012-03-01

This work is a study of the electrodeposition of zinc onto SAE 4140 steel electrodes using solutions containing zinc sulfate and bis(2-ethylhexyl) sodium sulfosuccinate (AOT). The influence of different parameters such as electrolyte concentration, electrodeposition time and temperature on the morphology of the electrodeposits was analyzed. The deposits were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction. The variation of open circuit potential over time in chloride solutions was also evaluated. The nucleation-growth process and consequently the morphology of the electrodeposits are modified in the presence of AOT. The surfactant induces the formation of a porous deposit.

Development of a diffraction imaging flow cytometer

PubMed Central

Jacobs, Kenneth M.; Lu, Jun Q.

2013-01-01

Diffraction images record angle-resolved distribution of scattered light from a particle excited by coherent light and can correlate highly with the 3D morphology of a particle. We present a jet-in-fluid design of flow chamber for acquisition of clear diffraction images in a laminar flow. Diffraction images of polystyrene spheres of different diameters were acquired and found to correlate highly with the calculated ones based on the Mie theory. Fast Fourier transform analysis indicated that the measured images can be used to extract sphere diameter values. These results demonstrate the significant potentials of high-throughput diffraction imaging flow cytometry for extracting 3D morphological features of cells. PMID:19794790

A biophysical signature of network affiliation and sensory processing in mitral cells

PubMed Central

Angelo, Kamilla; Rancz, Ede A.; Pimentel, Diogo; Hundahl, Christian; Hannibal, Jens; Fleischmann, Alexander; Pichler, Bruno; Margrie, Troy W.

2012-01-01

One defining characteristic of the mammalian brain is its neuronal diversity1. For a given region, substructure or layer and even cell type2, variability in neuronal morphology and connectivity2-5 persists. While it is well established that such cellular properties vary considerably according to neuronal type, the significant biophysical diversity of neurons of the same morphological class is typically averaged out and ignored. Here we show that the amplitude of hyperpolarization-evoked membrane potential sag recorded in olfactory bulb mitral cells is an emergent, homotypic property of local networks and sensory information processing. Simultaneous whole-cell recordings from pairs of cells reveal that the amount of hyperpolarization-evoked sag potential and current6 is stereotypic for mitral cells belonging to the same glomerular circuit. This is corroborated by a mosaic, glomerulus-based pattern of expression of the HCN2 subunit of the hyperpolarization-activated current (Ih) channel. Furthermore, inter-glomerular differences in both membrane potential sag and HCN2 protein are diminished when sensory input to glomeruli is genetically and globally altered so only one type of odorant receptor is universally expressed7. We therefore suggest that population diversity in the intrinsic profile of mitral cells reflect functional adaptations of distinct local circuits dedicated to processing subtly different odor-related information. PMID:22820253

Screening of novel actinobacteria and characterization of the potential isolates from mangrove sediment of south coastal India.

PubMed

Arumugam, T; Senthil Kumar, P; Kameshwar, R; Prapanchana, K

2017-06-01

The importance of the current research is to investigate the different types of samples from the various mangrove sediments; as source of actinobacteria from the mangrove wet soil. Potential isolate screening by antimicrobial activity and identified actinobacteria was characterized based on cultural morphology, physiological and biochemical characteristics. Three different types of media were used to isolate actinobacteria from various geographical region of mangrove soil sediment and the genotype locus was recognized by 16S rDNA. Totally 144 actinobacteria isolates were recovered from 10 samples using three media. The most active culture media in the isolation of actinobacteria were ISP2 and Glycerol Yeast Extract Agar. Among 144 isolates, 38 isolates (26.38%) exhibited antimicrobial activity. Out of 38 isolates, potentially active 2 cultures were further supported for morphological and biochemical characterization analysis. Most of the isolates were produced pharmaceutically important enzymes such as protease, amylase, lipase, cellulose and also revealed antimicrobial activity against tested microorganism. The enriched salt, pH and temperature tolerance of the actinobacteria isolates to discharge commercially valuable primary and secondary bioactive metabolites. The present results functionally characterize novel mangrove actinobacteria and their metabolites for commercial interest in pharmaceutical industry. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preparation of zein nanoparticles by using solution-enhanced dispersion with supercritical CO2 and elucidation with computational fluid dynamics.

PubMed

Li, Sining; Zhao, Yaping

2017-01-01

Nanoparticles have attracted more and more attention in the medicinal field. Zein is a biomacromolecule and can be used as a carrier for delivering active ingredients to prepare controlled release drugs. In this article, we presented the preparation of zein nanoparticles by solution-enhanced dispersion by supercritical CO 2 (SEDS) approach. Scanning electron microscopy and transmission electron microscopy were applied to characterize the size and morphology of the obtained particles. The nozzle structure and the CO 2 flow rate greatly affected the morphology and the size of the particles. The size of zein was able to be reduced to 50-350 nm according to the different conditions. The morphologies of the resultant zein were either sphere or the filament network consisted of nanoparticles. The influence of the nozzle structure and the CO 2 flow rate on the velocity field was elucidated by using computational fluid dynamics. The nozzle structure and the CO 2 flow rate greatly affected the distribution of the velocity field. However, a similar velocity field could also be obtained when the nozzle structure or the CO 2 flow rate, or both were different. Therefore, the influence of the nozzle structure and the CO 2 flow rate on the size and morphology of the particles, can boil down to the velocity field. The results demonstrated that the velocity field can be a potential criterion for producing nanoparticles with controllable morphology and size, which is useful to scale-up the SEDS process.

Intraspecific variation in fine root respiration and morphology in response to in situ soil nitrogen fertility in a 100-year-old Chamaecyparis obtusa forest.

PubMed

Makita, Naoki; Hirano, Yasuhiro; Sugimoto, Takanobu; Tanikawa, Toko; Ishii, Hiroaki

2015-12-01

Soil N fertility has an effect on belowground C allocation, but the physiological and morphological responses of individual fine root segments to variations in N availability under field conditions are still unclear. In this study, the direction and magnitude of the physiological and morphological function of fine roots in response to variable in situ soil N fertility in a forest site were determined. We measured the specific root respiration (Rr) rate, N concentration and morphology of fine root segments with 1-3 branching orders in a 100-year-old coniferous forest of Chamaecyparis obtusa. Higher soil N fertility induced higher Rr rates, root N concentration, and specific root length (SRL), and lower root tissue density (RTD). In all fertility levels, the Rr rates were significantly correlated positively with root N and SRL and negatively with RTD. The regression slopes of respiration with root N and RTD were significantly higher along the soil N fertility gradient. Although no differences in the slopes of Rr and SRL relationship were found across the levels, there were significant shifts in the intercept along the common slope. These results suggest that a contrasting pattern in intraspecific relationships between specific Rr and N, RTD, and SRL exists among soils with different N fertility. Consequently, substantial increases in soil N fertility would exert positive effects on organ-scale root performance by covarying the Rr, root N, and morphology for their potential nutrient and water uptake.

Allocation, morphology, physiology, architecture: the multiple facets of plant above- and below-ground responses to resource stress.

PubMed

Freschet, Grégoire T; Violle, Cyrille; Bourget, Malo Y; Scherer-Lorenzen, Michael; Fort, Florian

2018-06-01

Plants respond to resource stress by changing multiple aspects of their biomass allocation, morphology, physiology and architecture. To date, we lack an integrated view of the relative importance of these plastic responses in alleviating resource stress and of the consistency/variability of these responses among species. We subjected nine species (legumes, forbs and graminoids) to nitrogen and/or light shortages and measured 11 above-ground and below-ground trait adjustments critical in the alleviation of these stresses (plus several underlying traits). Nine traits out of 11 showed adjustments that improved plants' potential capacity to acquire the limiting resource at a given time. Above ground, aspects of plasticity in allocation, morphology, physiology and architecture all appeared important in improving light capture, whereas below ground, plasticity in allocation and physiology were most critical to improving nitrogen acquisition. Six traits out of 11 showed substantial heterogeneity in species plasticity, with little structuration of these differences within trait covariation syndromes. Such comprehensive assessment of the complex nature of phenotypic responses of plants to multiple stress factors, and the comparison of plant responses across multiple species, makes a clear case for the high (but largely overlooked) diversity of potential plastic responses of plants, and for the need to explore the potential rules structuring them. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

The morphological state space revisited: what do phylogenetic patterns in homoplasy tell us about the number of possible character states?

PubMed Central

Hoyal Cuthill, Jennifer F.

2015-01-01

Biological variety and major evolutionary transitions suggest that the space of possible morphologies may have varied among lineages and through time. However, most models of phylogenetic character evolution assume that the potential state space is finite. Here, I explore what the morphological state space might be like, by analysing trends in homoplasy (repeated derivation of the same character state). Analyses of ten published character matrices are compared against computer simulations with different state space models: infinite states, finite states, ordered states and an ‘inertial' model, simulating phylogenetic constraints. Of these, only the infinite states model results in evolution without homoplasy, a prediction which is not generally met by real phylogenies. Many authors have interpreted the ubiquity of homoplasy as evidence that the number of evolutionary alternatives is finite. However, homoplasy is also predicted by phylogenetic constraints on the morphological distance that can be traversed between ancestor and descendent. Phylogenetic rarefaction (sub-sampling) shows that finite and inertial state spaces do produce contrasting trends in the distribution of homoplasy. Two clades show trends characteristic of phylogenetic inertia, with decreasing homoplasy (increasing consistency index) as we sub-sample more distantly related taxa. One clade shows increasing homoplasy, suggesting exhaustion of finite states. Different clades may, therefore, show different patterns of character evolution. However, when parsimony uninformative characters are excluded (which may occur without documentation in cladistic studies), it may no longer be possible to distinguish inertial and finite state spaces. Interestingly, inertial models predict that homoplasy should be clustered among comparatively close relatives (parallel evolution), whereas finite state models do not. If morphological evolution is often inertial in nature, then homoplasy (false homology) may primarily occur between close relatives, perhaps being replaced by functional analogy at higher taxonomic scales. PMID:26640650

Jaw lever analysis of Hawaiian gobioid stream fishes: a simulation study of morphological diversity and functional performance.

PubMed

Maie, Takashi; Schoenfuss, Heiko L; Blob, Richard W

2009-08-01

Differences in feeding behavior and performance among the five native Hawaiian gobioid stream fishes (Sicyopterus stimpsoni, Lentipes concolor, Awaous guamensis, Stenogobius hawaiiensis, and Eleotris sandwicensis) have been proposed based on the skeletal anatomy of their jaws and dietary specialization. However, performance of the feeding apparatus likely depends on the proportions and configurations of the jaw muscles and the arrangement of the jaw skeleton. We used a published mathematical model of muscle function to evaluate potential differences in jaw closing performance and their correlations with morphology among these species. For example, high output force calculated for the adductor mandibulae muscles (A2 and A3) of both A. guamensis and E. sandwicensis matched expectations based on the morphology of these species because these muscles are larger than in the other species. In contrast, Stenogobius hawaiiensis exhibited an alternative morphological strategy for achieving high relative output forces of both A2 and A3, in which the placement and configuration of the muscles conveyed high mechanical advantage despite only moderate cross-sectional areas. These differing anatomical pathways to similar functional performance suggest a pattern of many-to-one mapping of morphology to performance. In addition, a functional differentiation between A2 and A3 was evident for all species, in which A2 was better suited for producing forceful jaw closing and A3 for rapid jaw closing. Thus, the diversity of feeding performance of Hawaiian stream gobies seems to reflect a maintenance of functional breadth through the retention of some primitive traits in combination with novel functional capacities in several species. (c) 2009 Wiley-Liss, Inc.

Morphology modification of gold nanoparticles from nanoshell to C-shape: Improved surface enhanced Raman scattering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xing, Ting-Yang; Zhu, Jian; Li, Jian-Jun

Morphology modification of nanostructures is of great interest, because it can be used to fabricate nanostructures which are hard to be done using other methods. Different from traditional lithographic technique which is slow and expensive, morphology modification is easy, cheap, and reproducible. In this paper, modification of the optical and morphological properties of a hollow gold nanoshell (HGNS) is achieved by using H{sub 2}O{sub 2} as an oxidizer. The reshaping of these nanostructures has been demonstrated as a consequence of an oxidation process in which HGNSs are dissolved by H{sub 2}O{sub 2} under the acidic conditions provided by HCl. Wemore » investigate the oxidation process by a transmission electron microscope and propose a reshaping model involving four different shapes (HGNS, HGNS with hole, gold nanoring, and C-shaped gold nanoparticle) which are corresponding to the oxidation products of HGNSs at different pH values. Besides, the surface enhanced Raman scattering (SERS) activity of each oxidation product has been evaluated by using rhodamine 6G as the Raman active probe. It has been observed that the C-shaped gold nanoparticles which are corresponding to the oxidation products at the minimum pH value have the highest SERS activity and this result can also be interpreted by discrete-dipole approximation simulations. We demonstrate that the morphology modification of HGNSs becomes possible in a controlled manner using wet chemistry and can be used in preparation of gold nanoparticles such as HGNS with hole, gold nanoring, and C-shaped gold nanoparticle with large SERS activity. These nanostructures must have potential use in many plasmonic areas, including sensing, catalysis, and biomedicine.« less

In-Kennel Behavior Predicts Length of Stay in Shelter Dogs

PubMed Central

Protopopova, Alexandra; Mehrkam, Lindsay Renee; Boggess, May Meredith; Wynne, Clive David Lawrence

2014-01-01

Previous empirical evaluations of training programs aimed at improving dog adoption rates assume that dogs exhibiting certain behaviors are more adoptable. However, no systematic data are available to indicate that the spontaneous behavior of shelter dogs has an effect on adopter preference. The aim of the present study was to determine whether any behaviors that dogs exhibit spontaneously in the presence of potential adopters were associated with the dogs' length of stay in the shelter. A sample of 289 dogs was videotaped for 1 min daily throughout their stay at a county shelter. To account for differences in adopter behavior, experimenters varied from solitary passive observers to pairs of interactive observers. Dogs behaved more attentively to active observers. To account for adopter preference for morphology, dogs were divided into “morphologically preferred” and “non-preferred” groups. Morphologically preferred dogs were small, long coated, ratters, herders, and lap dogs. No theoretically significant differences in behavior were observed between the two different dog morphologies. When accounting for morphological preference, three behaviors were found to have a significant effect on length of stay in all dogs: leaning or rubbing on the enclosure wall (increased median length of stay by 30 days), facing away from the front of the enclosure (increased by 15 days), and standing (increased by 7 days). When combinations of behaviors were assessed, back and forth motion was found to predict a longer stay (increased by 24 days). No consistent behavioral changes were observed due to time spent at the shelter. These findings will allow shelters to focus behavioral modification efforts only on behaviors likely to influence adopters' choices. PMID:25551460

Untangling elevation-related differences in the hippocampus in food-caching mountain chickadees: the effect of a uniform captive environment.

PubMed

Freas, C A; Bingman, K; Ladage, L D; Pravosudov, V V

2013-01-01

Variation in environmental conditions associated with differential selection on spatial memory has been hypothesized to result in evolutionary changes in the morphology of the hippocampus, a brain region involved in spatial memory. At the same time, it is well known that the morphology of the hippocampus might also be directly affected by environmental conditions. Understanding the role of environment-based plasticity is therefore critical when investigating potential adaptive evolutionary changes in the hippocampus associated with environmental variation. We previously demonstrated large elevation-related variation in hippocampus morphology in mountain chickadees over an extremely small spatial scale. We hypothesized that this variation is related to differential selection pressures associated with differences in winter climate severity along an elevation gradient, which make different demands on spatial memory used for food cache retrieval. Here, we tested whether such variation is experience based, generated by potential differences in the environment, by comparing the hippocampus morphology of chickadees from different elevations maintained in a uniform captive environment in a laboratory with those sampled directly from the wild. In addition, we compared hippocampal neuron soma size in chickadees sampled directly from the wild with those maintained in laboratory conditions with restricted and unrestricted spatial memory use via manipulation of food-caching experiences to test whether memory use can affect neuron soma size. There were significant elevation-related differences in hippocampus volume and the total number of hippocampal neurons, but not in neuron soma size, in captive birds. Captive environmental conditions were associated with a large reduction in hippocampus volume and neuron soma size, but not in the total number of neurons or in neuron soma size in other telencephalic regions. Restriction of memory use while in laboratory conditions produced no significant effects on hippocampal neuron soma size. Overall our results showed that captivity has a strong effect on hippocampus volume, which could be due, at least partly, to a reduction in neuron soma size specifically in the hippocampus, but it did not override elevation-related differences in hippocampus volume or in the total number of hippocampal neurons. These data are consistent with the idea of the adaptive nature of the elevation-related differences associated with selection on spatial memory, while at the same time demonstrating additional environment-based plasticity in hippocampus volume, but not in neuron numbers. Our results, however, cannot rule out that the differences between elevations might still be driven by some developmental or early posthatching conditions/experiences. © 2013 S. Karger AG, Basel.

Identification of normal and cancerous human colorectal muscularis propria by multiphoton microscopy in different sections

NASA Astrophysics Data System (ADS)

Zhou, Yi; Chen, Zhifen; Kang, Deyong; li, Lianhuang; Zhuo, Shuangmu; Zhu, Xiaoqin; Guan, Guoxian; Chen, Jianxin

2016-01-01

Multiphoton microscopy (MPM) based on two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) as a potential diagnostic tool is attractive. MPM can effectively provide information about morphological and biochemical changes in biological tissues at the molecular level. In this paper, we attempt to identify normal and cancerous human colorectal muscularis propria by multiphoton microscopy in different sections (both in transverse and longitudinal sections). The results show that MPM can display different microstructure changes in the transverse and longitudinal sections of colorectal muscularis propria. MPM also can quantitatively describe the alteration of collagen content between normal and cancerous muscle layers. These are important pathological findings that MPM images can bring more detailed complementary information about tissue architecture and cell morphology through observing the transverse and longitudinal sections of colorectal muscularis propria. This work demonstrates that MPM can be better for identifying the microstructural characteristics of normal and cancerous human colorectal muscularis propria in different sections.

Estimating the magnitude of morphoscapes: how to measure the morphological component of biodiversity in relation to habitats using geometric morphometrics

NASA Astrophysics Data System (ADS)

Fontaneto, Diego; Panisi, Martina; Mandrioli, Mauro; Montardi, Dario; Pavesi, Maurizio; Cardini, Andrea

2017-08-01

Ecological indicators are currently developed to account for the different facets of loss of biological diversity due to direct or indirect effects of human activities. Most ecological indicators include species richness as a metric. Others, such as functional traits and phylogenetic diversity, account for differences in species, even when species richness is the same. Here, we describe and apply a different indicator, called morphoscape dimension, accounting for morphological variability across habitats in a geographical region. We use the case of ground beetles (Coleoptera: Carabidae) in four different habitats in the Po Plain in Northern Italy to exemplify how to quantify the magnitude of the morphological space (i.e. the dimension of the morphoscape) occupied by the species in each habitat using geometric morphometrics. To this aim, we employed a variety of metrics of morphological disparity related to univariate size, and more complex multivariate shape and form. Our `proof of concept' suggests that metrics assessing size and form might largely tend to simply mirror the information provided by species richness, whereas shape morphoscape disparity may be able to account for non-trivial differences in species traits amongst habitats. This is indicated by the woodland morphoscape being on average bigger than that of crops, the most species-rich habitat, despite having almost 20% less species. We conclude suggesting that the analysis of morphoscape dimension has the potential to become a new additional and complimentary tool in the hands of conservation biologists and ecologists to explore and quantify habitat complexity and inform decisions on management and conservation based on a wide set of ecological indicators.

Effect of traffic and driving characteristics on morphology of atmospheric soot particles at freeway on-ramps.

PubMed

China, Swarup; Salvadori, Neila; Mazzoleni, Claudio

2014-03-18

Vehicles represent a major source of soot in urban environments. Knowledge of the morphology and mixing of soot particles is fundamental to understand their potential health and climatic impacts. We investigate 5738 single particles collected at six different cloverleaf freeway on-ramps in Southern Michigan, using 2D images from scanning electron microscopy. Of those, 3364 particles are soot. We present an analysis of the morphological and mixing properties of those soot particles. The relative abundance of soot particles shows a positive association with traffic density (number of vehicles per minute). A classification of the mixing state of freshly emitted soot particles shows that most of them are bare (or thinly coated) (72%) and some are partly coated (22%). We find that the fractal dimension of soot particles (one of the most relevant morphological descriptors) varies from site to site, and increases with increasing vehicle specific power that represents the driving/engine load conditions, and with increasing percentage of vehicles older than 15 years. Our results suggest that driving conditions, and vehicle age and type have significant influence on the morphology of soot particles.

Host Diet Affects the Morphology of Monarch Butterfly Parasites.

PubMed

Hoang, Kevin; Tao, Leiling; Hunter, Mark D; de Roode, Jacobus C

2017-06-01

Understanding host-parasite interactions is essential for ecological research, wildlife conservation, and health management. While most studies focus on numerical traits of parasite groups, such as changes in parasite load, less focus is placed on the traits of individual parasites such as parasite size and shape (parasite morphology). Parasite morphology has significant effects on parasite fitness such as initial colonization of hosts, avoidance of host immune defenses, and the availability of resources for parasite replication. As such, understanding factors that affect parasite morphology is important in predicting the consequences of host-parasite interactions. Here, we studied how host diet affected the spore morphology of a protozoan parasite ( Ophryocystis elektroscirrha ), a specialist parasite of the monarch butterfly ( Danaus plexippus ). We found that different host plant species (milkweeds; Asclepias spp.) significantly affected parasite spore size. Previous studies have found that cardenolides, secondary chemicals in host plants of monarchs, can reduce parasite loads and increase the lifespan of infected butterflies. Adding to this benefit of high cardenolide milkweeds, we found that infected monarchs reared on milkweeds of higher cardenolide concentrations yielded smaller parasites, a potentially hidden characteristic of cardenolides that may have important implications for monarch-parasite interactions.

Morphology, stratigraphy, and surface roughness properties of Venusian lava flow fields

NASA Astrophysics Data System (ADS)

Byrnes, Jeffrey M.; Crown, David A.

2002-10-01

Morphologic characteristics, flow stratigraphy, and radar backscatter properties of five lava flow fields on Venus (Turgmam Fluctus, Zipaltonal Fluctus, Tuli Mons/Uilata Fluctus, Var Mons, and Mylitta Fluctus) were examined to understand flow field emplacement mechanisms and relationships to other surface processes. These analyses indicate that the flow fields studied developed through emplacement of numerous, thin flow units, presumably over extended periods of time. Although the Venusian fields display flow morphologies similar to those observed within terrestrial flow fields, the Venusian flow units are significantly larger and have a larger range of radar backscatter coefficients. Both simple and compound flow emplacement appear to have occurred within the flow fields. A potential correlation between flow rheology and radar brightness is suggested by differences in planform morphology, apparent flow thickness, and apparent sensitivity to topography between bright and dark flows. Distributary flow morphologies may result from tube-fed flows, and postemplacement modification by processes such as flow inflation and crustal foundering is consistent with discrete zones of increased radar brightness within individual flow lobes. Mapping of these flow fields does not indicate any simple evolutionary trend in eruptive/resurfacing style within the flow fields, or any consistent temporal sequence relative to other tectonic and volcanic features.

Selection on an antagonistic behavioral trait can drive rapid genital coevolution in the burying beetle, Nicrophorus vespilloides

PubMed Central

Hopwood, Paul E.; Head, Megan L.; Jordan, Eleanor J.; Carter, Mauricio J.; Davey, Emma; Moore, Allen J.; Royle, Nick J.

2016-01-01

Male and female genital morphology varies widely across many taxa, and even among populations. Disentangling potential sources of selection on genital morphology is problematic because each sex is predicted to respond to adaptations in the other due to reproductive conflicts of interest. To test how variation in this sexual conflict trait relates to variation in genital morphology we used our previously developed artificial selection lines for high and low repeated mating rates. We selected for high and low repeated mating rates using monogamous pairings to eliminate contemporaneous female choice and male–male competition. Male and female genital shape responded rapidly to selection on repeated mating rate. High and low mating rate lines diverged from control lines after only 10 generations of selection. We also detected significant patterns of male and female genital shape coevolution among selection regimes. We argue that because our selection lines differ in sexual conflict, these results support the hypothesis that sexually antagonistic coevolution can drive the rapid divergence of genital morphology. The greatest divergence in morphology corresponded with lines in which the resolution of sexual conflict over mating rate was biased in favor of male interests. PMID:27144373

Correlated evolution of beak morphology and song in the neotropical woodcreeper radiation.

PubMed

Derryberry, Elizabeth Perrault; Seddon, Nathalie; Claramunt, Santiago; Tobias, Joseph Andrew; Baker, Adam; Aleixo, Alexandre; Brumfield, Robb Thomas

2012-09-01

Mating signals may diversify as a byproduct of morphological adaptation to different foraging niches, potentially driving speciation. Although many studies have focused on the direct influence of ecological and sexual selection on signal divergence, the role of indirect mechanisms remains poorly understood. Using phenotypic and molecular datasets, we explored the interplay between morphological and vocal evolution in an avian radiation characterized by dramatic beak variation, the Neotropical woodcreepers (Dendrocolaptinae). We found evidence of a trade-off between the rate of repetition of song syllables and frequency bandwidth: slow paced songs had either narrow or wide frequency bandwidths, and bandwidth decreased as song pace increased. This bounded phenotypic space for song structure supports the hypothesis that passerine birds face a motor constraint during song production. Diversification of acoustic characters within this bounded space was correlated with diversification of beak morphology. In particular, species with larger beaks produced slower songs with narrower frequency bandwidths, suggesting that ecological selection on beak morphology influences the diversification of woodcreeper songs. Because songs in turn mediate mate choice and species recognition in birds, these results indicate a broader role for ecology in avian diversification. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

Arginine-based cationic liposomes for efficient in vitro plasmid DNA delivery with low cytotoxicity.

PubMed

Sarker, Satya Ranjan; Aoshima, Yumiko; Hokama, Ryosuke; Inoue, Takafumi; Sou, Keitaro; Takeoka, Shinji

2013-01-01

Currently available gene delivery vehicles have many limitations such as low gene delivery efficiency and high cytotoxicity. To overcome these drawbacks, we designed and synthesized two cationic lipids comprised of n-tetradecyl alcohol as the hydrophobic moiety, 3-hydrocarbon chain as the spacer, and different counterions (eg, hydrogen chloride [HCl] salt or trifluoroacetic acid [TFA] salt) in the arginine head group. Cationic lipids were hydrated in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer to prepare cationic liposomes and characterized in terms of their size, zeta potential, phase transition temperature, and morphology. Lipoplexes were then prepared and characterized in terms of their size and zeta potential in the absence or presence of serum. The morphology of the lipoplexes was determined using transmission electron microscopy and atomic force microscopy. The gene delivery efficiency was evaluated in neuronal cells and HeLa cells and compared with that of lysine-based cationic assemblies and Lipofectamine™ 2000. The cytotoxicity level of the cationic lipids was investigated and compared with that of Lipofectamine™ 2000. We synthesized arginine-based cationic lipids having different counterions (ie, HCl-salt or TFA-salt) that formed cationic liposomes of around 100 nm in size. In the absence of serum, lipoplexes prepared from the arginine-based cationic liposomes and plasmid (p) DNA formed large aggregates and attained a positive zeta potential. However, in the presence of serum, the lipoplexes were smaller in size and negative in zeta potential. The morphology of the lipoplexes was vesicular. Arginine-based cationic liposomes with HCl-salt showed the highest transfection efficiency in PC-12 cells. However, arginine-based cationic liposomes with TFA salt showed the highest transfection efficiency in HeLa cells, regardless of the presence of serum, with very low associated cytotoxicity. The gene delivery efficiency of amino acid-based cationic assemblies is influenced by the amino acids (ie, arginine or lysine) present as the hydrophilic head group and their associated counterions.

Arginine-based cationic liposomes for efficient in vitro plasmid DNA delivery with low cytotoxicity

PubMed Central

Sarker, Satya Ranjan; Aoshima, Yumiko; Hokama, Ryosuke; Inoue, Takafumi; Sou, Keitaro; Takeoka, Shinji

2013-01-01

Background Currently available gene delivery vehicles have many limitations such as low gene delivery efficiency and high cytotoxicity. To overcome these drawbacks, we designed and synthesized two cationic lipids comprised of n-tetradecyl alcohol as the hydrophobic moiety, 3-hydrocarbon chain as the spacer, and different counterions (eg, hydrogen chloride [HCl] salt or trifluoroacetic acid [TFA] salt) in the arginine head group. Methods Cationic lipids were hydrated in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer to prepare cationic liposomes and characterized in terms of their size, zeta potential, phase transition temperature, and morphology. Lipoplexes were then prepared and characterized in terms of their size and zeta potential in the absence or presence of serum. The morphology of the lipoplexes was determined using transmission electron microscopy and atomic force microscopy. The gene delivery efficiency was evaluated in neuronal cells and HeLa cells and compared with that of lysine-based cationic assemblies and Lipofectamine™ 2000. The cytotoxicity level of the cationic lipids was investigated and compared with that of Lipofectamine™ 2000. Results We synthesized arginine-based cationic lipids having different counterions (ie, HCl-salt or TFA-salt) that formed cationic liposomes of around 100 nm in size. In the absence of serum, lipoplexes prepared from the arginine-based cationic liposomes and plasmid (p) DNA formed large aggregates and attained a positive zeta potential. However, in the presence of serum, the lipoplexes were smaller in size and negative in zeta potential. The morphology of the lipoplexes was vesicular. Arginine-based cationic liposomes with HCl-salt showed the highest transfection efficiency in PC-12 cells. However, arginine-based cationic liposomes with TFA salt showed the highest transfection efficiency in HeLa cells, regardless of the presence of serum, with very low associated cytotoxicity. Conclusion The gene delivery efficiency of amino acid-based cationic assemblies is influenced by the amino acids (ie, arginine or lysine) present as the hydrophilic head group and their associated counterions. PMID:23630419

Quantitative morphometrical characterization of human pronuclear zygotes.

PubMed

Beuchat, A; Thévenaz, P; Unser, M; Ebner, T; Senn, A; Urner, F; Germond, M; Sorzano, C O S

2008-09-01

Identification of embryos with high implantation potential remains a challenge in in vitro fertilization (IVF). Subjective pronuclear (PN) zygote scoring systems have been developed for that purpose. The aim of this work was to provide a software tool that enables objective measuring of morphological characteristics of the human PN zygote. A computer program was created to analyse zygote images semi-automatically, providing precise morphological measurements. The accuracy of this approach was first validated by comparing zygotes from two different IVF centres with computer-assisted measurements or subjective scoring. Computer-assisted measurement and subjective scoring were then compared for their ability to classify zygotes with high and low implantation probability by using a linear discriminant analysis. Zygote images coming from the two IVF centres were analysed with the software, resulting in a series of precise measurements of 24 variables. Using subjective scoring, the cytoplasmic halo was the only feature which was significantly different between the two IVF centres. Computer-assisted measurements revealed significant differences between centres in PN centring, PN proximity, cytoplasmic halo and features related to nucleolar precursor bodies distribution. The zygote classification error achieved with the computer-assisted measurements (0.363) was slightly inferior to that of the subjective ones (0.393). A precise and objective characterization of the morphology of human PN zygotes can be achieved by the use of an advanced image analysis tool. This computer-assisted analysis allows for a better morphological characterization of human zygotes and can be used for classification.

Degradation of Methylammonium Lead Iodide Perovskite Structures through Light and Electron Beam Driven Ion Migration

PubMed Central

2016-01-01

Organometal halide perovskites show promising features for cost-effective application in photovoltaics. The material instability remains a major obstacle to broad application because of the poorly understood degradation pathways. Here, we apply simultaneous luminescence and electron microscopy on perovskites for the first time, allowing us to monitor in situ morphology evolution and optical properties upon perovskite degradation. Interestingly, morphology, photoluminescence (PL), and cathodoluminescence of perovskite samples evolve differently upon degradation driven by electron beam (e-beam) or by light. A transversal electric current generated by a scanning electron beam leads to dramatic changes in PL and tunes the energy band gaps continuously alongside film thinning. In contrast, light-induced degradation results in material decomposition to scattered particles and shows little PL spectral shifts. The differences in degradation can be ascribed to different electric currents that drive ion migration. Moreover, solution-processed perovskite cuboids show heterogeneity in stability which is likely related to crystallinity and morphology. Our results reveal the essential role of ion migration in perovskite degradation and provide potential avenues to rationally enhance the stability of perovskite materials by reducing ion migration while improving morphology and crystallinity. It is worth noting that even moderate e-beam currents (86 pA) and acceleration voltages (10 kV) readily induce significant perovskite degradation and alter their optical properties. Therefore, attention has to be paid while characterizing such materials using scanning electron microscopy or transmission electron microscopy techniques. PMID:26804213

Sulfur Nanoparticles with Novel Morphologies Coupled with Brain-Targeting Peptides RVG as a New Type of Inhibitor Against Metal-Induced Aβ Aggregation.

PubMed

Sun, Jing; Xie, Wenjie; Zhu, Xufeng; Xu, Mengmeng; Liu, Jie

2018-04-18

Functionalized nanomaterials, which have been applied widely to inhibit amyloid-β protein (Aβ) aggregation, show enormous potential in the field of prevention and treatment of Alzheimer's disease (AD). A significant body of data has demonstrated that the morphology and size of nanomaterials have remarkable effects on their biological behaviors. In this work, we proposed and designed three kinds of brain-targeting sulfur nanoparticles (RVG@Met@SNPs) with novel morphologies (volute-like, tadpole-like, and sphere-like) and investigated the effect of different RVG@Met@SNPs on Aβ-Cu 2+ complex aggregation and their corresponding neurotoxicity. Among them, the sphere-like nanoparticles (RVG@Met@SS) exhibited the most effective inhibitory activity, due to their unique mini size effect, and they reduced 61.6% the Aβ-Cu 2+ complex aggregation and increased 92.4% SH-SY5Y cell viability in a dose of 10 μg/mL. In vitro and in vivo, the abilities of different morphologies of RVG@Met@SNPs to cross the blood-brain barrier (BBB) and target brain parenchymal cells were significantly different. Moreover, improvements in learning disability and cognitive loss were shown in the transgenic AD mice model using the Morris water maze test after multiple doses of RVG@Met@SNPs treatment. In general, the purpose of this research is to develop a biological application of sulfur nanoparticles and to provide a novel functionalized nanomaterial to treat AD.

[Relationship between mitochondrial DNA copy number, membrane potential of human embryo and embryo morphology].

PubMed

Zhao, H; Teng, X M; Li, Y F

2017-11-25

Objective: To explore the relationship between the embryo with the different morphological types in the third day and its mitochondrial copy number, the membrane potential. Methods: Totally 117 embryos with poor development after normal fertilization and were not suitable transferred in the fresh cycle and 106 frozen embryos that were discarded voluntarily by infertility patients with in vitro fertilization-embryo transfer after successful pregnancy were selected. According to evaluation of international standard in embryos, all cleavage stage embryos were divided into class Ⅰ frozen embryo group ( n= 64), class Ⅱ frozen embryo group ( n= 42) and class Ⅲ fresh embryonic group (not transplanted embryos; n= 117). Real-time PCR and confocal microscopy methods were used to detect mitochondrial DNA (mtDNA) copy number and the mitochondrial membrane potential of a single embryo. The differences between embryo quality and mtDNA copy number and membrane potential of each group were compared. Results: The copy number of mtDNA and the mitochondrial membrane potential in class Ⅲ fresh embryonic group [(1.7±1.0)×10(5) copy/μl, 1.56±0.32] were significantly lower than those in class Ⅰ frozen embryo group [(3.4±1.7)×10(5) copy/μl, 2.66±0.21] and class Ⅱ frozen embryo group [(2.6±1.2)×10(5) copy/μl, 1.80±0.32; all P< 0.05]. The copy number of mtDNA and the mitochondrial membrane potential in classⅠ frozen embryo group were significantly higher than those in classⅡ frozen embryo group (both P< 0.05). Conclusion: The mtDNA copy number and the mitochondrial membrane potential of embryos of the better quality embryo are higher.

Ecoregions and stream morphology in eastern Oklahoma

USGS Publications Warehouse

Splinter, D.K.; Dauwalter, D.C.; Marston, R.A.; Fisher, W.L.

2010-01-01

Broad-scale variables (i.e., geology, topography, climate, land use, vegetation, and soils) influence channel morphology. How and to what extent the longitudinal pattern of channel morphology is influenced by broad-scale variables is important to fluvial geomorphologists and stream ecologists. In the last couple of decades, there has been an increase in the amount of interdisciplinary research between fluvial geomorphologists and stream ecologists. In a historical context, fluvial geomorphologists are more apt to use physiographic regions to distinguish broad-scale variables, while stream ecologists are more apt to use the concept of an ecosystem to address the broad-scale variables that influence stream habitat. For this reason, we designed a study using ecoregions, which uses physical and biological variables to understand how landscapes influence channel processes. Ecoregions are delineated by similarities in geology, climate, soils, land use, and potential natural vegetation. In the fluvial system, stream form and function are dictated by processes observed throughout the fluvial hierarchy. Recognizing that stream form and function should differ by ecoregion, a study was designed to evaluate how the characteristics of stream channels differed longitudinally among three ecoregions in eastern Oklahoma, USA: Boston Mountains, Ozark Highlands, and Ouachita Mountains. Channel morphology of 149 stream reaches was surveyed in 1st- through 4th-order streams, and effects of drainage area and ecoregion on channel morphology was evaluated using multiple regressions. Differences existed (?????0.05) among ecoregions for particle size, bankfull width, and width/depth ratio. No differences existed among ecoregions for gradient or sinuosity. Particle size was smallest in the Ozark Highlands and largest in the Ouachita Mountains. Bankfull width was larger in the Ozark Highlands than in the Boston Mountains and Ouachita Mountains in larger streams. Width/depth ratios of the Boston Mountains and Ozark Highlands were not statistically different. Significant differences existed, however, between the Boston Mountains and Ozark Highlands when compared individually to the Ouachita Mountains. We found that ecoregions afforded a good spatial structure that can help in understanding longitudinal trends in stream reach morphology surveyed at the reach scale. The hierarchy of the fluvial system begins within a broad, relatively homogenous setting that imparts control on processes that affect stream function. Ecoregions provide an adequate regional division to begin a large-scale geomorphic study of processes in stream channels. ?? 2010 Elsevier B.V.

Purple head broccoli (Brassica oleracea L. var. italica Plenck), a functional food crop for antioxidant and anticancer potential.

PubMed

Chaudhary, Ashun; Choudhary, Sonika; Sharma, Upendra; Vig, Adarsh Pal; Singh, Bikram; Arora, Saroj

2018-05-01

Natural foods are used in many folks and household treatments and have immense potential to treat a serious complication and health benefits, in addition to the basic nutritional values. These food products improve health, delay the aging process, increase life expectancy, and possibly prevent chronic diseases. Purple head Brassica oleracea L. var. italica Plenck is one of such foods and in current studies was explored for chemical compounds at different development stages by gas chromatography-mass spectrometry. Antioxidant potential was explored employing different assays like molybdate ion reduction, DPPH, superoxide anion radical scavenging and plasmid nicking assay. Inspired by antioxidant activity results, we further explored these extracts for antiproliferative potential by morphological changes, cell cycle analysis, measurement of intracellular peroxides and mitochondrial membrane potential changes. Current study provides the scientific basis for the use of broccoli as easily affordable potent functional food.

A Conserved Developmental Patterning Network Produces Quantitatively Different Output in Multiple Species of Drosophila

PubMed Central

Meyer, Miriah; Wunderlich, Zeba; Simirenko, Lisa; Luengo Hendriks, Cris L.; Keränen, Soile V. E.; Henriquez, Clara; Knowles, David W.; Biggin, Mark D.; Eisen, Michael B.; DePace, Angela H.

2011-01-01

Differences in the level, timing, or location of gene expression can contribute to alternative phenotypes at the molecular and organismal level. Understanding the origins of expression differences is complicated by the fact that organismal morphology and gene regulatory networks could potentially vary even between closely related species. To assess the scope of such changes, we used high-resolution imaging methods to measure mRNA expression in blastoderm embryos of Drosophila yakuba and Drosophila pseudoobscura and assembled these data into cellular resolution atlases, where expression levels for 13 genes in the segmentation network are averaged into species-specific, cellular resolution morphological frameworks. We demonstrate that the blastoderm embryos of these species differ in their morphology in terms of size, shape, and number of nuclei. We present an approach to compare cellular gene expression patterns between species, while accounting for varying embryo morphology, and apply it to our data and an equivalent dataset for Drosophila melanogaster. Our analysis reveals that all individual genes differ quantitatively in their spatio-temporal expression patterns between these species, primarily in terms of their relative position and dynamics. Despite many small quantitative differences, cellular gene expression profiles for the whole set of genes examined are largely similar. This suggests that cell types at this stage of development are conserved, though they can differ in their relative position by up to 3–4 cell widths and in their relative proportion between species by as much as 5-fold. Quantitative differences in the dynamics and relative level of a subset of genes between corresponding cell types may reflect altered regulatory functions between species. Our results emphasize that transcriptional networks can diverge over short evolutionary timescales and that even small changes can lead to distinct output in terms of the placement and number of equivalent cells. PMID:22046143

Morphological recognition of Globigerinoides ruber morphotypes and their susceptibility to diagenetic alteration in the eastern Mediterranean Sea

NASA Astrophysics Data System (ADS)

Kontakiotis, G.; Antonarakou, A.; Mortyn, P. G.; Drinia, H.; Anastasakis, G.; Zarkogiannis, S.; Möbius, J.

2017-10-01

Planktonic foraminiferal geochemistry presents a valuable archive for paleoceanographic reconstructions. However in high salinity and carbonate super-saturated settings, precipitation of inorganic calcite onto foraminiferal tests can potentially alter the primary geochemical signal, biasing Mg/Ca ratios and ensuing paleoceanographic reconstructions. Here we utilize test biometrics (specifically related to the compression and elongation of the last chambers) to identify four distinct morphotypes (labelled A-D) of the paleoceanographically important planktonic foraminifer species Globigerinoides ruber, and further evaluate their susceptibility to diagenetic alteration from a suite of surface sediments in the eastern Mediterranean Sea. The three distinguished morphotypes (A-C) correspond to previously recognized morphotypes ("Normal", "Platys", "Elongate" respectively) in the Mediterranean Sea, while the remaining (D or "Twin") was designated for the first time. We also compare Scanning Electron Microscopy (SEM) observations performed on four distinguished morphotypes, indicative of potential diagenetic alteration influence. We identified 3 different overgrowth stages (OGA1-OGA3), as a function of geography in the study area. The early diagenesis degrees (involving all the morphotypes) are only geographically distinct along the eastern Mediterranean (increasing to the south), since the morphology does not play a role in the likelihood of diagenetic alteration. Particularly, in the north Aegean Sea, SEM analyses reveal the absence or limited presence of an overgrowth imprint in all recognized morphotypes, while in the central-south Aegean and Levantine Seas they show higher amplitudes of diagenetic overprint supporting the general trend to advanced diagenetic alteration. The semi-enclosed oligotrophic nature and high salinity of this setting, in combination with the different degree of carbonate precipitation and calcite super-saturation between the sub-basins, could be the most plausible explanation for the observed diagenetic stages. The ecological divergence between the morphotypes, determined by different controlling factors (depth habitats, growth optimum/stressed conditions, productivity, stratification, near-/offshore-conditions), in combination with their different test morphologies (related to shell porosity), control directly their distribution pattern. Regardless of the exact mechanism of early diagenetic processes, our results remove one potential source of uncertainty in Mg/Ca-T reconstructions in such highly evaporitive basins of the (sub)tropics, and potentially open the door to the calculation of a multivariate calibration with greater accuracy. However, further investigations should extend this approach to test the robustness of our findings in a number of similar oceanic settings.

Measurement and significance of sperm morphology

PubMed Central

Menkveld, Roelof; Holleboom, Cas AG; Rhemrev, Johann PT

2011-01-01

The measurement or evaluation and clinical significance of human sperm morphology has always been and still is a controversial aspect of the semen analysis for the determination of a male's fertility potential. In this review the background of the development of the evaluation criteria for sperm morphology will be discussed. Aspects of criticism on the strict criteria definition and use of the criteria for sperm morphology evaluation will be discussed as well as possible reasons for the decline in normal sperm morphology values and how we can compromise for this phenomenon resulting in the very low normal reference value as published in the 2010 WHO manual for the Examination and Processing of Human Semen. One of the possible solutions may be to give more attention to a limited number of abnormal sperm morphology categories and the inclusion of sperm morphology patterns. It is concluded in this review that if done correctly and with care and with strict application of existing guidelines as outlined in the 2010 WHO manual, sperm morphology measurement still has a very important role to play in the clinical evaluation of male fertility potential. PMID:21076438

Degree of Hybridization in Seed Stands of Pinus engelmannii Carr. In the Sierra Madre Occidental, Durango, Mexico

PubMed Central

Ávila-Flores, Israel Jaime; Hernández-Díaz, José Ciro; González-Elizondo, Maria Socorro; Prieto-Ruíz, José Ángel; Wehenkel, Christian

2016-01-01

Hybridization is an important evolutionary force, because interspecific gene transfer can introduce more new genetic material than is directly generated by mutations. Pinus engelmannii Carr. is one of the nine most common pine species in the pine-oak forest ecoregion in the state of Durango, Mexico. This species is widely harvested for lumber and is also used in reforestation programmes. Interspecific hybrids between P.engelmannii and Pinus arizonica Engelm. have been detected by morphological analysis. The presence of hybrids in P. engelmannii seed stands may affect seed quality and reforestation success. Therefore, the goals of this research were to identify introgressive hybridization between P. engelmannii and other pine species in eight seed stands of this species in Durango, Mexico, and to examine how hybrid proportion is related to mean genetic dissimilarity between trees in these stands, using Amplified Fragment Length Polymorphism (AFLP) markers and morphological traits. Differences in the average current annual increment of putative hybrids and pure trees were also tested for statistical significance. Morphological and genetic analyses of 280 adult trees were carried out. Putative hybrids were found in all the seed stands studied. The hybrids did not differ from the pure trees in vigour or robustness. All stands with putative P. engelmannii hybrids detected by both AFLPs and morphological traits showed the highest average values of the Tanimoto distance, which indicates: i) more heterogeneous genetic material, ii) higher genetic variation and therefore iii) the higher evolutionary potential of these stands, and iv) that the morphological differentiation (hybrid/not hybrid) is strongly associated with the Tanimoto distance per stand. We conclude that natural pairwise hybrids are very common in the studied stands. Both morphological and molecular approaches are necessary to confirm the genetic identity of forest reproductive material. PMID:27064490

Associations of serum adiponectin with skeletal muscle morphology and insulin sensitivity.

PubMed

Ingelsson, Erik; Arnlöv, Johan; Zethelius, Björn; Vasan, Ramachandran S; Flyvbjerg, Allan; Frystyk, Jan; Berne, Christian; Hänni, Arvo; Lind, Lars; Sundström, Johan

2009-03-01

Skeletal muscle morphology and function are strongly associated with insulin sensitivity. The objective of the study was to test the hypothesis that circulating adiponectin is associated with skeletal muscle morphology and that adiponectin mediates the relation of muscle morphology to insulin sensitivity. This was a cross-sectional investigation of 461 men aged 71 yr, participants of the community-based Uppsala Longitudinal Study of Adult Men study. Measures included serum adiponectin, insulin sensitivity measured with euglycemic insulin clamp technique, and capillary density and muscle fiber composition determined from vastus lateralis muscle biopsies. In multivariable linear regression models (adjusting for age, physical activity, fasting glucose, and pharmacological treatment for diabetes), serum adiponectin levels rose with increasing capillary density (beta, 0.30 per 50 capillaries per square millimeter increase; P = 0.041) and higher proportion of type I muscle fibers (beta, 0.27 per 10% increase; P = 0.036) but declined with a higher proportion of type IIb fibers (beta, -0.39 per 10% increase; P = 0.014). Using bootstrap methods to examine the potential role of adiponectin in associations between muscle morphology and insulin sensitivity and the associations of capillary density (beta difference, 0.041; 95% confidence interval 0.001, 0.085) and proportion of type IIb muscle fibers (beta difference, -0.053; 95% confidence interval -0.107, -0.002) with insulin sensitivity were significantly attenuated when adiponectin was included in the models. Circulating adiponectin concentrations were higher with increasing skeletal muscle capillary density and in individuals with higher proportion of slow oxidative muscle fibers. Furthermore, our results indicate that adiponectin could be a partial mediator of the relations between skeletal muscle morphology and insulin sensitivity.

Degree of Hybridization in Seed Stands of Pinus engelmannii Carr. In the Sierra Madre Occidental, Durango, Mexico.

PubMed

Ávila-Flores, Israel Jaime; Hernández-Díaz, José Ciro; González-Elizondo, Maria Socorro; Prieto-Ruíz, José Ángel; Wehenkel, Christian

2016-01-01

Hybridization is an important evolutionary force, because interspecific gene transfer can introduce more new genetic material than is directly generated by mutations. Pinus engelmannii Carr. is one of the nine most common pine species in the pine-oak forest ecoregion in the state of Durango, Mexico. This species is widely harvested for lumber and is also used in reforestation programmes. Interspecific hybrids between P.engelmannii and Pinus arizonica Engelm. have been detected by morphological analysis. The presence of hybrids in P. engelmannii seed stands may affect seed quality and reforestation success. Therefore, the goals of this research were to identify introgressive hybridization between P. engelmannii and other pine species in eight seed stands of this species in Durango, Mexico, and to examine how hybrid proportion is related to mean genetic dissimilarity between trees in these stands, using Amplified Fragment Length Polymorphism (AFLP) markers and morphological traits. Differences in the average current annual increment of putative hybrids and pure trees were also tested for statistical significance. Morphological and genetic analyses of 280 adult trees were carried out. Putative hybrids were found in all the seed stands studied. The hybrids did not differ from the pure trees in vigour or robustness. All stands with putative P. engelmannii hybrids detected by both AFLPs and morphological traits showed the highest average values of the Tanimoto distance, which indicates: i) more heterogeneous genetic material, ii) higher genetic variation and therefore iii) the higher evolutionary potential of these stands, and iv) that the morphological differentiation (hybrid/not hybrid) is strongly associated with the Tanimoto distance per stand. We conclude that natural pairwise hybrids are very common in the studied stands. Both morphological and molecular approaches are necessary to confirm the genetic identity of forest reproductive material.

Assessing Species-specific Contributions To Craniofacial Development Using Quail-duck Chimeras

PubMed Central

Fish, Jennifer L.; Schneider, Richard A.

2014-01-01

The generation of chimeric embryos is a widespread and powerful approach to study cell fates, tissue interactions, and species-specific contributions to the histological and morphological development of vertebrate embryos. In particular, the use of chimeric embryos has established the importance of neural crest in directing the species-specific morphology of the craniofacial complex. The method described herein utilizes two avian species, duck and quail, with remarkably different craniofacial morphology. This method greatly facilitates the investigation of molecular and cellular regulation of species-specific pattern in the craniofacial complex. Experiments in quail and duck chimeric embryos have already revealed neural crest-mediated tissue interactions and cell-autonomous behaviors that regulate species-specific pattern in the craniofacial skeleton, musculature, and integument. The great diversity of neural crest derivatives suggests significant potential for future applications of the quail-duck chimeric system to understanding vertebrate development, disease, and evolution. PMID:24962088

Effect of silk sericin on morphology and structure of calcium carbonate crystal

NASA Astrophysics Data System (ADS)

Zhao, Rui-Bo; Han, Hua-Feng; Ding, Shao; Li, Ze-Hao; Kong, Xiang-Dong

2013-06-01

In this paper, silk sericin was employed to regulate the mineralization of calcium carbonate (CaCO3). CaCO3 composite particles were prepared by the precipitation reaction of sodium carbonate with calcium chloride solution in the presence of silk sericin. The as-prepared samples were collected at different reaction time to study the crystallization process of CaCO3 by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The results showed that silk sericin significantly affected the morphology and crystallographic polymorph of CaCO3. With increasing the reaction time, the crystal phase of CaCO3 transferred from calcite dominated to vaterite dominated mixtures, while the morphology of CaCO3 changed from disk-like calcite crystal to spherical vaterite crystal. These studies showed the potential of silk sericin used as a template molecule to control the growth of inorganic crystal.

Effects of IAA, IBA, NAA, and GA3 on rooting and morphological features of Melissa officinalis L. stem cuttings.

PubMed

Sevik, Hakan; Guney, Kerim

2013-01-01

This study analyzed the potential of producing Melissa officinalis L. using stem cuttings. Four different hormones (IAA, IBA, NAA, and GA3) were applied to the cuttings, with and without buds, in two doses (1000 mg/L and 5000 mg/L), and after 60 days, 10 morphological characteristics of newly generated plants were detected, and a statistical analysis was carried out. The results of the study show that the cuttings with at least one bud must be used in order to produce M. officinalis using stem cuttings. Even though the auxin group hormones (IAA, IBA, and NAA) do not have an apparent effect on rooting percentage, these hormones were detected to affect the morphological characteristics of the newly generated plants, especially root generation. GA3 application has a considerable effect on stem height.

Homogeneous Analysis of the Dust Morphology of Transition Disks Observed with ALMA: Investigating Dust Trapping and the Origin of the Cavities

NASA Astrophysics Data System (ADS)

Pinilla, P.; Tazzari, M.; Pascucci, I.; Youdin, A. N.; Garufi, A.; Manara, C. F.; Testi, L.; van der Plas, G.; Barenfeld, S. A.; Canovas, H.; Cox, E. G.; Hendler, N. P.; Pérez, L. M.; van der Marel, N.

2018-05-01

We analyze the dust morphology of 29 transition disks (TDs) observed with Atacama Large (sub-)Millimeter Array (ALMA) at (sub-)millimeter emission. We perform the analysis in the visibility plane to characterize the total flux, cavity size, and shape of the ring-like structure. First, we found that the M dust–M ⋆ relation is much flatter for TDs than the observed trends from samples of class II sources in different star-forming regions. This relation demonstrates that cavities open in high (dust) mass disks, independent of the stellar mass. The flatness of this relation contradicts the idea that TDs are a more evolved set of disks. Two potential reasons (not mutually exclusive) may explain this flat relation: the emission is optically thick or/and millimeter-sized particles are trapped in a pressure bump. Second, we discuss our results of the cavity size and ring width in the context of different physical processes for cavity formation. Photoevaporation is an unlikely leading mechanism for the origin of the cavity of any of the targets in the sample. Embedded giant planets or dead zones remain as potential explanations. Although both models predict correlations between the cavity size and the ring shape for different stellar and disk properties, we demonstrate that with the current resolution of the observations, it is difficult to obtain these correlations. Future observations with higher angular resolution observations of TDs with ALMA will help discern between different potential origins of cavities in TDs.

What Is the Influence of Morphological Knowledge in the Early Stages of Reading Acquisition Among Low SES Children? A Graphical Modeling Approach

PubMed Central

Colé, Pascale; Cavalli, Eddy; Duncan, Lynne G.; Theurel, Anne; Gentaz, Edouard; Sprenger-Charolles, Liliane; El-Ahmadi, Abdessadek

2018-01-01

Children from low-SES families are known to show delays in aspects of language development which underpin reading acquisition such as vocabulary and listening comprehension. Research on the development of morphological skills in this group is scarce, and no studies exist in French. The present study investigated the involvement of morphological knowledge in the very early stages of reading acquisition (decoding), before reading comprehension can be reliably assessed. We assessed listening comprehension, receptive vocabulary, phoneme awareness, morphological awareness as well as decoding, word reading and non-verbal IQ in 703 French first-graders from low-SES families after 3 months of formal schooling (November). Awareness of derivational morphology was assessed using three oral tasks: Relationship Judgment (e.g., do these words belong to the same family or not? heat-heater … ham-hammer); Lexical Sentence Completion [e.g., Someone who runs is a …? (runner)]; and Non-lexical Sentence Completion [e.g., Someone who lums is a…? (lummer)]. The tasks differ on implicit/explicit demands and also tap different kinds of morphological knowledge. The Judgement task measures the phonological and semantic properties of the morphological relationship and the Sentence Completion tasks measure knowledge of morphological production rules. Data were processed using a graphical modeling approach which offers key information about how skills known to be involved in learning to read are organized in memory. This modeling approach was therefore useful in revealing a potential network which expresses the conditional dependence structure between skills, after which recursive structural equation modeling was applied to test specific hypotheses. Six main conclusions can be drawn from these analyses about low SES reading acquisition: (1) listening comprehension is at the heart of the reading acquisition process; (2) word reading depends directly on phonemic awareness and indirectly on listening comprehension; (3) decoding depends on word reading; (4) Morphological awareness and vocabulary have an indirect influence on word reading via both listening comprehension and phoneme awareness; (5) the components of morphological awareness assessed by our tasks have independent relationships with listening comprehension; and (6) neither phonemic nor morphological awareness influence vocabulary directly. The implications of these results with regard to early reading acquisition among low SES groups are discussed. PMID:29725313

What Is the Influence of Morphological Knowledge in the Early Stages of Reading Acquisition Among Low SES Children? A Graphical Modeling Approach.

PubMed

Colé, Pascale; Cavalli, Eddy; Duncan, Lynne G; Theurel, Anne; Gentaz, Edouard; Sprenger-Charolles, Liliane; El-Ahmadi, Abdessadek

2018-01-01

Children from low-SES families are known to show delays in aspects of language development which underpin reading acquisition such as vocabulary and listening comprehension. Research on the development of morphological skills in this group is scarce, and no studies exist in French. The present study investigated the involvement of morphological knowledge in the very early stages of reading acquisition (decoding), before reading comprehension can be reliably assessed. We assessed listening comprehension, receptive vocabulary, phoneme awareness, morphological awareness as well as decoding, word reading and non-verbal IQ in 703 French first-graders from low-SES families after 3 months of formal schooling (November). Awareness of derivational morphology was assessed using three oral tasks: Relationship Judgment (e.g., do these words belong to the same family or not? heat-heater … ham-hammer); Lexical Sentence Completion [e.g., Someone who runs is a …? (runner)]; and Non-lexical Sentence Completion [e.g., Someone who lums is a…? (lummer)]. The tasks differ on implicit/explicit demands and also tap different kinds of morphological knowledge. The Judgement task measures the phonological and semantic properties of the morphological relationship and the Sentence Completion tasks measure knowledge of morphological production rules. Data were processed using a graphical modeling approach which offers key information about how skills known to be involved in learning to read are organized in memory. This modeling approach was therefore useful in revealing a potential network which expresses the conditional dependence structure between skills, after which recursive structural equation modeling was applied to test specific hypotheses. Six main conclusions can be drawn from these analyses about low SES reading acquisition: (1) listening comprehension is at the heart of the reading acquisition process; (2) word reading depends directly on phonemic awareness and indirectly on listening comprehension; (3) decoding depends on word reading; (4) Morphological awareness and vocabulary have an indirect influence on word reading via both listening comprehension and phoneme awareness; (5) the components of morphological awareness assessed by our tasks have independent relationships with listening comprehension; and (6) neither phonemic nor morphological awareness influence vocabulary directly. The implications of these results with regard to early reading acquisition among low SES groups are discussed.

Phenotypic plasticity in haptoral structures of Ligophorus cephali (Monogenea: Dactylogyridae) on the flathead mullet (Mugil cephalus): a geometric morphometric approach.

PubMed

Rodríguez-González, Abril; Míguez-Lozano, Raúl; Llopis-Belenguer, Cristina; Balbuena, Juan Antonio

2015-04-01

Evaluating phenotypic plasticity in attachment organs of parasites can provide information on the capacity to colonise new hosts and illuminate evolutionary processes driving host specificity. We analysed the variability in shape and size of the dorsal and ventral anchors of Ligophorus cephali from Mugil cephalus by means of geometric morphometrics and multivariate statistics. We also assessed the morphological integration between anchors and between the roots and points in order to gain insight into their functional morphology. Dorsal and ventral anchors showed a similar gradient of overall shape variation, but the amount of localised changes was much higher in the former. Statistical models describing variations in shape and size revealed clear differences between anchors. The dorsal anchor/bar complex seems more mobile than the ventral one in Ligophorus, and these differences may reflect different functional roles in attachment to the gills. The lower residual variation associated with the ventral anchor models suggests a tighter control of their shape and size, perhaps because these anchors seem to be responsible for firmer attachment and their size and shape would allow more effective responses to characteristics of the microenvironment within the individual host. Despite these putative functional differences, the high level of morphological integration indicates a concerted action between anchors. In addition, we found a slight, although significant, morphological integration between roots and points in both anchors, which suggests that a large fraction of the observed phenotypic variation does not compromise the functional role of anchors as levers. Given the low level of genetic variation in our sample, it is likely that much of the morphological variation reflects host-driven plastic responses. This supports the hypothesis of monogenean specificity through host-switching and rapid speciation. The present study demonstrates the potential of geometric morphometrics to provide new and previously unexplored insights into the functional morphology of attachment and evolutionary processes of host-parasite coevolution. Copyright © 2015 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Self-generated morphology in lagoon reefs

PubMed Central

Hamblin, Michael G.

2015-01-01

The three-dimensional form of a coral reef develops through interactions and feedbacks between its constituent organisms and their environment. Reef morphology therefore contains a potential wealth of ecological information, accessible if the relationships between morphology and ecology can be decoded. Traditionally, reef morphology has been attributed to external controls such as substrate topography or hydrodynamic influences. Little is known about inherent reef morphology in the absence of external control. Here we use reef growth simulations, based on observations in the cellular reefs of Western Australia’s Houtman Abrolhos Islands, to show that reef morphology is fundamentally determined by the mechanical behaviour of the reef-building organisms themselves—specifically their tendency to either remain in place or to collapse. Reef-building organisms that tend to remain in place, such as massive and encrusting corals or coralline algae, produce nodular reefs, whereas those that tend to collapse, such as branching Acropora, produce cellular reefs. The purest reef growth forms arise in sheltered lagoons dominated by a single type of reef builder, as in the branching Acropora-dominated lagoons of the Abrolhos. In these situations reef morphology can be considered a phenotype of the predominant reef building organism. The capacity to infer coral type from reef morphology can potentially be used to identify and map specific coral habitat in remotely sensed images. More generally, identifying ecological mechanisms underlying other examples of self-generated reef morphology can potentially improve our understanding of present-day reef ecology, because any ecological process capable of shaping a reef will almost invariably be an important process in real time on the living reef. PMID:26175962

Ordered to isotropic morphology transition in pattern-directed dewetting of polymer thin films on substrates with different feature heights.

PubMed

Roy, Sudeshna; Mukherjee, Rabibrata

2012-10-24

Controlled dewetting of a thin polymer film on a topographically patterned substrate is an interesting approach for aligning isotropic dewetted structures. In this article, we investigate the influence of substrate feature height (H(S)) on the dewetting pathway and final pattern morphology by studying the dewetting of polystyrene (PS) thin films on grating substrates with identical periodicity (λ(P) = 1.5 μm), but H(S) varying between 10 nm and 120 nm. We identify four distinct categories of final dewetted morphology, with different extent of ordering: (1) array of aligned droplets (H(S) ≈ 120 nm); (2) aligned undulating ribbons (H(S) ≈ 70-100 nm); (3) multilength scale structures with coexisting large droplets uncorrelated to the substrate and smaller droplets/ribbons aligned along the stripes (H(S) ≈ 40-60 nm); and (4) large droplets completely uncorrelated to the substrate (H(S) < 25 nm). The distinct morphologies across the categories are attributed to two major factors: (a) whether the as-cast film is continuous (H(S)≤ 80 nm) or discontinuous (H(S)≥ 100 nm) and (b) in case of a continuous film, whether the film ruptures along each substrate stripe (H(S)≥ 70 nm) or with nucleation of random holes that are not correlated to the substrate features (H(S)≤ 60 nm). While the ranges of H(S) values indicated in the parentheses are valid for PS films with an equivalent thickness (h(E)) ≈ 50.3 nm on a flat substrate, a change in h(E) merely alters the cut-off values of H(S), as the final dewetted morphologies and transition across categories remain generically unaltered. We finally show that the structures obtained by dewetting on different H(S) substrates exhibits different levels of hydrophobicity because of combined spatial variation of chemical and topographic contrast along the surface. Thus, the work reported in this article can find potential application in fabricating surfaces with controlled wettability.

Fungal Morphology in Industrial Enzyme Production--Modelling and Monitoring.

PubMed

Quintanilla, Daniela; Hagemann, Timo; Hansen, Kim; Gernaey, Krist V

2015-01-01

Filamentous fungi are widely used in the biotechnology industry for the production of industrial enzymes. Thus, considerable work has been done with the purpose of characterizing these processes. The ultimate goal of these efforts is to be able to control and predict fermentation performance on the basis of "standardized" measurements in terms of morphology, rheology, viscosity, mass transfer and productivity. However, because the variables are connected or dependent on each other, this task is not trivial. The aim of this review article is to gather available information in order to explain the interconnectivity between the different variables in submerged fermentations. An additional factor which makes the characterization of a fermentation broth even more challenging is that the data obtained are also dependent on the way they have been collected-meaning which technologies or probes have been used, and on the way the data is interpreted-i.e. which models were applied. The main filamentous fungi used in industrial fermentation are introduced, ranging from Trichoderma reesei to Aspergillus species. Due to the fact that secondary metabolites, like antibiotics, are not to be considered bulk products, organisms like e.g. Penicillium chrysogenum are just briefly touched upon for the description of some characterization techniques. The potential for development of different morphological phenotypes is discussed as well, also in view of what this could mean to productivity and-equally important-the collection of the data. An overview of the state of the art techniques for morphology characterization is provided, discussing methods that finally can be employed as the computational power has grown sufficiently in the recent years. Image analysis (IA) clearly benefits most but it also means that methods like near infrared measurement (NIR), capacitance and on-line viscosity now provide potential alternatives as powerful tools for characterizing morphology. These measuring techniques, and to some extent their combination, allow obtaining the data necessary for supporting the creation of mathematical models describing the fermentation process. An important part of this article will indeed focus on describing the different models, and on discussing their importance to fermentations of filamentous fungi in general. The main conclusion is that it has not yet been attempted to develop an overarching model that spans across strains and scales, as most studies indeed conclude that their respective results might be strain specific and not necessarily valid across scales.

Floral Morphology and Development in Quillajaceae and Surianaceae (Fabales), the Species-poor Relatives of Leguminosae and Polygalaceae

PubMed Central

Bello, M. A.; Hawkins, J. A.; Rudall, P. J.

2007-01-01

Background and Aims Molecular phylogenies have suggested a new circumscription for Fabales to include Leguminosae, Quillajaceae, Surianaceae and Polygalaceae. However, recent attempts to reconstruct the interfamilial relationships of the order have resulted in several alternative hypotheses, including a sister relationship between Quillajaceae and Surianaceae, the two species-poor families of Fabales. Here, floral morphology and ontogeny of these two families are investigated to explore evidence of a potential relationship between them. Floral traits are discussed with respect to early radiation in the order. Method Floral buds of representatives of Quillajaceae and Surianaceae were dissected and observed using light microscopy and scanning electron microscopy. Key Results Quillajaceae and Surianaceae possess some common traits, such as inflorescence morphology and perianth initiation, but development and organization of their reproductive whorls differ. In Quillaja, initiation of the diplostemonous androecium is unidirectional, overlapping with the petal primordia. In contrast, Suriana is obdiplostemonous, and floral organ initiation is simultaneous. Independent initiation of five carpels is common to both Quillaja and Suriana, but subsequent development differs; the antesepalous carpels of Quillaja become fused proximally and exhibit two rows of ovules, and in Suriana the gynoecium is apocarpous, gynobasic, with antepetalous biovulate carpels. Conclusions Differences in the reproductive development and organization of Quillajaceae and Surianaceae cast doubt on their potential sister relationship. Instead, Quillaja resembles Leguminosae in some floral traits, a hypothesis not suggested by molecular-based phylogenies. Despite implicit associations of zygomorphy with species-rich clades and actinomorphy with species-poor families in Fabales, this correlation sometimes fails due to high variation in floral symmetry. Studies considering specific derived clades and reproductive biology could address more precise hypotheses of key innovation and differential diversification in the order. PMID:17906327

Floral morphology and development in Quillajaceae and Surianaceae (Fabales), the species-poor relatives of Leguminosae and Polygalaceae.

PubMed

Bello, M A; Hawkins, J A; Rudall, P J

2008-06-01

Molecular phylogenies have suggested a new circumscription for Fabales to include Leguminosae, Quillajaceae, Surianaceae and Polygalaceae. However, recent attempts to reconstruct the interfamilial relationships of the order have resulted in several alternative hypotheses, including a sister relationship between Quillajaceae and Surianaceae, the two species-poor families of Fabales. Here, floral morphology and ontogeny of these two families are investigated to explore evidence of a potential relationship between them. Floral traits are discussed with respect to early radiation in the order. Floral buds of representatives of Quillajaceae and Surianaceae were dissected and observed using light microscopy and scanning electron microscopy. Quillajaceae and Surianaceae possess some common traits, such as inflorescence morphology and perianth initiation, but development and organization of their reproductive whorls differ. In Quillaja, initiation of the diplostemonous androecium is unidirectional, overlapping with the petal primordia. In contrast, Suriana is obdiplostemonous, and floral organ initiation is simultaneous. Independent initiation of five carpels is common to both Quillaja and Suriana, but subsequent development differs; the antesepalous carpels of Quillaja become fused proximally and exhibit two rows of ovules, and in Suriana the gynoecium is apocarpous, gynobasic, with antepetalous biovulate carpels. Differences in the reproductive development and organization of Quillajaceae and Surianaceae cast doubt on their potential sister relationship. Instead, Quillaja resembles Leguminosae in some floral traits, a hypothesis not suggested by molecular-based phylogenies. Despite implicit associations of zygomorphy with species-rich clades and actinomorphy with species-poor families in Fabales, this correlation sometimes fails due to high variation in floral symmetry. Studies considering specific derived clades and reproductive biology could address more precise hypotheses of key innovation and differential diversification in the order.

Surface area loss mechanisms of Pt3Co nanocatalysts in proton exchange membrane fuel cells

NASA Astrophysics Data System (ADS)

Rasouli, S.; Ortiz Godoy, R. A.; Yang, Z.; Gummalla, M.; Ball, S. C.; Myers, D.; Ferreira, P. J.

2017-03-01

Pt3Co catalyst nanoparticles of 4.9 nm size present on the cathode side of a PEMFC membrane-electrode assembly (MEA) were analyzed by transmission electron microscopy after 10 K voltage cycles under different operating conditions. The operating conditions include baseline (0.4-0.95 V, 80° C, 100% Relative Humidity (RH)), high potential (0.4-1.05 V, 80° C, 100% RH), high temperature (0.4-0.95 V, 90° C, 100% RH), and low humidity (0.4-0.95 V, 80° C, 30% RH). Particle growth and particle loss to the membrane is more severe in the high potential sample than in the high temperature and baseline MEAs, while no significant particle growth and particle precipitation in the membrane can be observed in the low humidity sample. Particles with different morphologies were seen in the cathode including: 1-Spherical individual particles resulting from modified electro-chemical Ostwald ripening and 2-aggregated and coalesced particles resulting from either necking of two or more particles or preferential deposition of Pt between particles with consequent bridging. The difference in the composition of these morphologies results in composition variations through the cathode from cathode/diffusion media (DM) to the cathode/membrane interface.

Manus track preservation bias as a key factor for assessing trackmaker identity and quadrupedalism in basal ornithopods.

PubMed

Castanera, Diego; Vila, Bernat; Razzolini, Novella L; Falkingham, Peter L; Canudo, José I; Manning, Phillip L; Galobart, Angel

2013-01-01

The Las Cerradicas site (Tithonian-Berriasian), Teruel, Spain, preserves at least seventeen dinosaur trackways, some of them formerly attributed to quadrupedal ornithopods, sauropods and theropods. The exposure of new track evidence allows a more detailed interpretation of the controversial tridactyl trackways as well as the modes of locomotion and taxonomic affinities of the trackmakers. Detailed stratigraphic analysis reveals four different levels where footprints have been preserved in different modes. Within the tridactyl trackways, manus tracks are mainly present in a specific horizon relative to surface tracks. The presence of manus tracks is interpreted as evidence of an ornithopod trackmaker. Cross-sections produced from photogrammetric digital models show different depths of the pes and manus, suggesting covariance in loading between the forelimbs and the hindlimbs. Several features (digital pads, length/width ratio, claw marks) of some ornithopod pes tracks from Las Cerradicas are reminiscent of theropod pedal morphology. This morphological convergence, combined with the shallow nature of the manus tracks, which reduces preservation potential, opens a new window into the interpretation of these tridactyl tracks. Thus, trackmaker assignations during the Jurassic-Cretaceous interval of purported theropod trackways may potentially represent ornithopods. Moreover, the Las Cerradicas trackways are further evidence for quadrupedalism among some basal small- to medium-sized ornithopods from this time interval.

Kangaroo versus porcine aortic valve tissue--valve geometry morphology, tensile strength and calcification potential.

PubMed

Neethling, W M; Papadimitriou, J M; Swarts, E; Hodge, A J

2000-06-01

Valve related factors and patient related factors are responsible for calcification of valvular bioprostheses. Recent studies showed different donor and recipient species have different influences on the total calcification rate of bioprostheses. This study was performed to evaluate and compare Kangaroo aortic valve leaflets with porcine aortic valve leaflets. Experimental design. Prospective study. Setting. Cardio-thoracic experimental research of a university department. Glutaraldehyde-fixed Kangaroo and porcine valve leaflets were evaluated in vitro according to valve geometry (internal diameter and leaflet thickness), morphology (light and electron microscopy) and tensile strength. In vivo evaluation consisted of implantation in a rat model for 8 weeks, Von Kossa stain for calcium and atomic absorption spectrophotometry for total extractable calcium content. Kangaroo valves indicated a smaller internal valve diameter as well as a thinner valve leaflet (p<0.01, ANOVA) at corresponding body weight, less proteoglycan spicules in the fibrosa, increased elasticity (p<0.05) and low calcification potential (p<0.01, confidence interval 95%). Kangaroo aortic valve leaflets have different valvular qualities compared to porcine valve tissue. Kangaroo valve leaflets are significantly superior to porcine valve leaflets as far as calcification is concerned. These results are encouraging and suggest further in vivo evaluation in a larger animal model before clinical application can be considered.

Personality and morphological traits affect pigeon survival from raptor attacks.

PubMed

Santos, Carlos D; Cramer, Julia F; Pârâu, Liviu G; Miranda, Ana C; Wikelski, Martin; Dechmann, Dina K N

2015-10-22

Personality traits have recently been shown to impact fitness in different animal species, potentially making them similarly relevant drivers as morphological and life history traits along the evolutionary pathways of organisms. Predation is a major force of natural selection through its deterministic effects on individual survival, but how predation pressure has helped to shape personality trait selection, especially in free-ranging animals, remains poorly understood. We used high-precision GPS tracking to follow whole flocks of homing pigeons (Columba livia) with known personalities and morphology during homing flights where they were severely predated by raptors. This allowed us to determine how the personality and morphology traits of pigeons may affect their risk of being predated by raptors. Our survival model showed that individual pigeons, which were more tolerant to human approach, slower to escape from a confined environment, more resistant to human handling, with larger tarsi, and with lighter plumage, were more likely to be predated by raptors. We provide rare empirical evidence that the personality of prey influences their risk of being predated under free-ranging circumstances.

Personality and morphological traits affect pigeon survival from raptor attacks

PubMed Central

Santos, Carlos D.; Cramer, Julia F.; Pârâu, Liviu G.; Miranda, Ana C.; Wikelski, Martin; Dechmann, Dina K. N.

2015-01-01

Personality traits have recently been shown to impact fitness in different animal species, potentially making them similarly relevant drivers as morphological and life history traits along the evolutionary pathways of organisms. Predation is a major force of natural selection through its deterministic effects on individual survival, but how predation pressure has helped to shape personality trait selection, especially in free-ranging animals, remains poorly understood. We used high-precision GPS tracking to follow whole flocks of homing pigeons (Columba livia) with known personalities and morphology during homing flights where they were severely predated by raptors. This allowed us to determine how the personality and morphology traits of pigeons may affect their risk of being predated by raptors. Our survival model showed that individual pigeons, which were more tolerant to human approach, slower to escape from a confined environment, more resistant to human handling, with larger tarsi, and with lighter plumage, were more likely to be predated by raptors. We provide rare empirical evidence that the personality of prey influences their risk of being predated under free-ranging circumstances. PMID:26489437

Changes in cell morphology due to plasma membrane wounding by acoustic cavitation

PubMed Central

Schlicher, Robyn K.; Hutcheson, Joshua D.; Radhakrishna, Harish; Apkarian, Robert P.; Prausnitz, Mark R.

2010-01-01

Acoustic cavitation-mediated wounding (i.e., sonoporation) has great potential to improve medical and laboratory applications requiring intracellular uptake of exogenous molecules; however, the field lacks detailed understanding of cavitation-induced morphological changes in cells and their relative importance. Here, we present an in-depth study of the effects of acoustic cavitation on cells using electron and confocal microscopy coupled with quantitative flow cytometry. High resolution images of treated cells show that morphologically different types of blebs can occur after wounding conditions caused by ultrasound exposure as well as by mechanical shear and strong laser ablation. In addition, these treatments caused wound-induced non-lytic necrotic death resulting in cell bodies we call wound-derived perikarya (WD-P). However, only cells exposed to acoustic cavitation experienced ejection of intact nuclei and nearly instant lytic necrosis. Quantitative analysis by flow cytometry indicates that wound-derived perikarya are the dominant morphology of nonviable cells, except at the strongest wounding conditions, where nuclear ejection accounts for a significant portion of cell death after ultrasound exposure. PMID:20350691

Controlled morphology and size of curcumin using ultrasound in supercritical CO2 antisolvent.

PubMed

Jia, Jingfu; Wang, Wucong; Gao, Yahui; Zhao, Yaping

2015-11-01

Controllable morphology and size of crystal materials prepared by using a supercritical antisolvent (SAS) technique is still challenge. In this study, ultrasound was introduced into the SAS process to produce the particles of curcumin, a model compound. The effects of ultrasound power on the particle morphology and size were investigated in the range of 0 and 240 W at three different pressures. The observation of jet flow indicated ultrasound could accelerate the mixing speed between the liquid solution and the CO2, and thus reduced the gaseous region and the local saturation gradient. Mixed polymorphic and uniform particles of the curcumin were produced at a low and high mixing speed, respectively, confirmed by scanning electron microscopy. The needle- or rod-like particle, irregular lumpy particle and nano spherical particle were generated with the increase of the ultrasound power, attributed to the changes of the degree of supersaturation. Therefore, the ultrasound can be potentially applied to adjust the morphology and size of the crystal materials in supercritical CO2 antisolvent. Copyright © 2015 Elsevier B.V. All rights reserved.

Morphological Evolution of Nanocluster Aggregates and Single Crystals in Alkaline Zinc Electrodeposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Desai, D; Turney, DE; Anantharaman, B

2014-04-24

The morphology of Zn electrodeposits is studied on carbon-coated transmission electron microscopy grids. At low over-potentials (eta = -50 mV), the morphology develops by aggregation at two distinct length scales: similar to 5 nm diameter monocrystalline nanoclusters form similar to 50 nm diameter polycrystalline aggregates, and the aggregates form a branched network. Epitaxial (00 (0) over bar2) growth above an overpotential of vertical bar eta(c)vertical bar > 125 mV leads to the formation of hexagonal single crystals up to 2 mu m in diameter. Potentiostatic current transients were used to calculate the nucleation rate from Scharifker et al.'s model. Themore » exp(eta) dependence of the nucleation rates indicates that atomistic nucleation theory explains the nucleation process better than Volmer-Weber theory. A kinetic model is provided using the rate equations of vapor solidification to simulate the evolution of the different morphologies. On solving these equations, we show that aggregation is attributed to cluster impingement and cluster diffusion while single-crystal formation is attributed to direct attachment.« less

Morphological Characterization of the Action Potential Initiation Segment in GnRH Neuron Dendrites and Axons of Male Mice.

PubMed

Herde, Michel K; Herbison, Allan E

2015-11-01

GnRH neurons are the final output neurons of the hypothalamic network controlling fertility in mammals. In the present study, we used ankyrin G immunohistochemistry and neurobiotin filling of live GnRH neurons in brain slices from GnRH-green fluorescent protein transgenic male mice to examine in detail the location of action potential initiation in GnRH neurons with somata residing at different locations in the basal forebrain. We found that the vast majority of GnRH neurons are bipolar in morphology, elaborating a thick (primary) and thinner (secondary) dendrite from opposite poles of the soma. In addition, an axon-like process arising predominantly from a proximal dendrite was observed in a subpopulation of GnRH neurons. Ankyrin G immunohistochemistry revealed the presence of a single action potential initiation zone ∼27 μm in length primarily in the secondary dendrite of GnRH neurons and located 30 to 140 μm distant from the cell soma, depending on the type of process and location of the cell body. In addition to dendrites, the GnRH neurons with cell bodies located close to hypothalamic circumventricular organs often elaborated ankyrin G-positive axon-like structures. Almost all GnRH neurons (>90%) had their action potential initiation site in a process that initially, or ultimately after a hairpin loop, was coursing in the direction of the median eminence. These studies indicate that action potentials are initiated in different dendritic and axonal compartments of the GnRH neuron in a manner that is dependent partly on the neuroanatomical location of the cell body.

Species specific effects of three morphologically different belowground seagrasses on sediment properties

NASA Astrophysics Data System (ADS)

Rattanachot, Ekkalak; Prathep, Anchana

2015-12-01

Roots and rhizomes of seagrass play an important role in coastline zone by anchoring the substrate firmly which prevent resuspension and also controlling sediment biogeochemistry. The aim of this study was to compare the physical and chemical differences of sediments for 3 seagrass species, which have different root morphology between summer (February 2013) and the monsoon month (September 2013). Seven seagrass communities were studied and are: the mono stand of Halophila ovalis, Thalassia hemprichii, and Cymodocea rotundata, the mixed patches of H. ovalis with T. hemprichii, H. ovalis with C. rotundata, and T. hemprichii with C. rotundata and the mixed patches of 3 seagrass species. The roots of seagrasses were the main driver of differences in sediment properties; the branched, long root species, C. rotundata, showed an increasing redox potential by means of oxygen releasing from their roots. The unbranched, long root with dense root hair species, T. hemprichii, tended to cause more poorly sorted sediments. The carbon storage was also estimated and results showed a trend of higher organic carbon density was in the multispecific patches, the mono specific patches and bare sand, respectively. Season also influenced the sediment properties; high wave action in the monsoon stirred up the sediments, this led to lower organic carbon density and high redox potential. Our results suggest that the roots of seagrass species both increase and decrease sediment properties.

Local anaphor licensing in an SOV language: implications for retrieval strategies

PubMed Central

Kush, Dave; Phillips, Colin

2014-01-01

Because morphological and syntactic constraints govern the distribution of potential antecedents for local anaphors, local antecedent retrieval might be expected to make equal use of both syntactic and morphological cues. However, previous research (e.g., Dillon et al., 2013) has shown that local antecedent retrieval is not susceptible to the same morphological interference effects observed during the resolution of morphologically-driven grammatical dependencies, such as subject-verb agreement checking (e.g., Pearlmutter et al., 1999). Although this lack of interference has been taken as evidence that syntactic cues are given priority over morphological cues in local antecedent retrieval, the absence of interference could also be the result of a confound in the materials used: the post-verbal position of local anaphors in prior studies may obscure morphological interference that would otherwise be visible if the critical anaphor were in a different position. We investigated the licensing of local anaphors (reciprocals) in Hindi, an SOV language, in order to determine whether pre-verbal anaphors are subject to morphological interference from feature-matching distractors in a way that post-verbal anaphors are not. Computational simulations using a version of the ACT-R parser (Lewis and Vasishth, 2005) predicted that a feature-matching distractor should facilitate the processing of an unlicensed reciprocal if morphological cues are used in antecedent retrieval. In a self-paced reading study we found no evidence that distractors eased processing of an unlicensed reciprocal. However, the presence of a distractor increased difficulty of processing following the reciprocal. We discuss the significance of these results for theories of cue selection in retrieval. PMID:25414680

Bayes Forest: a data-intensive generator of morphological tree clones

PubMed Central

Järvenpää, Marko; Åkerblom, Markku; Raumonen, Pasi; Kaasalainen, Mikko

2017-01-01

Abstract Detailed and realistic tree form generators have numerous applications in ecology and forestry. For example, the varying morphology of trees contributes differently to formation of landscapes, natural habitats of species, and eco-physiological characteristics of the biosphere. Here, we present an algorithm for generating morphological tree “clones” based on the detailed reconstruction of the laser scanning data, statistical measure of similarity, and a plant growth model with simple stochastic rules. The algorithm is designed to produce tree forms, i.e., morphological clones, similar (and not identical) in respect to tree-level structure, but varying in fine-scale structural detail. Although we opted for certain choices in our algorithm, individual parts may vary depending on the application, making it a general adaptable pipeline. Namely, we showed that a specific multipurpose procedural stochastic growth model can be algorithmically adjusted to produce the morphological clones replicated from the target experimentally measured tree. For this, we developed a statistical measure of similarity (structural distance) between any given pair of trees, which allows for the comprehensive comparing of the tree morphologies by means of empirical distributions describing the geometrical and topological features of a tree. Finally, we developed a programmable interface to manipulate data required by the algorithm. Our algorithm can be used in a variety of applications for exploration of the morphological potential of the growth models (both theoretical and experimental), arising in all sectors of plant science research. PMID:29020742

The importance of transmission electron microscopy analysis of spermatozoa: Diagnostic applications and basic research.

PubMed

Moretti, Elena; Sutera, Gaetano; Collodel, Giulia

2016-06-01

This review is aimed at discussing the role of ultrastructural studies on human spermatozoa and evaluating transmission electron microscopy as a diagnostic tool that can complete andrology protocols. It is clear that morphological sperm defects may explain decreased fertilizing potential and acquire particular value in the field of male infertility. Electron microscopy is the best method to identify systematic or monomorphic and non-systematic or polymorphic sperm defects. The systematic defects are characterized by a particular anomaly that affects the vast majority of spermatozoa in a semen sample, whereas a heterogeneous combination of head and tail defects found in variable percentages are typically non-systematic or polymorphic sperm defects. A correct diagnosis of these specific sperm alterations is important for choosing the male infertility's therapy and for deciding to turn to assisted reproduction techniques. Transmission electron microscopy (TEM) also represents a valuable method to explore the in vitro effects of different compounds (for example drugs with potential spermicidal activity) on the morphology of human spermatozoa. Finally, TEM used in combination with immunohistochemical techniques, integrates structural and functional aspects that provide a wide horizon in the understanding of sperm physiology and pathology. transmission electron microscopy: TEM; World Health Organization: WHO; light microscopy: LM; motile sperm organelle morphology examination: MSOME; intracytoplasmic morphologically selected sperm injection: IMSI; intracytoplasmic sperm injection: ICSI; dysplasia of fibrous sheath: DFS; primary ciliary dyskinesia: PCD; outer dense fibers: ODF; assisted reproduction technologies: ART; scanning electron microscopy: SEM; polyvinylpirrolidone: PVP; tert-butylhydroperoxide: TBHP.

Morphologic, biometric, and isoenzyme characterization of Trichuris suis.

PubMed

Oliveros, R; Cutillas, C; Arias, P; Guevara, D

1998-06-01

Trichuris suis isolates were collected from the cecum of Sus scrofa domestica (pig) and S. s. scrofa (wild boar). Morphology and biometry studies were carried out. Morphology studies showed the existence of typical caudal papillae in males of T. suis from wild boars, but no other difference was observed in the biometric parameters (total length, esophageal length, posterior-portion body length, and spicular length) of T. suis isolated from either host. Individual extracts were subjected to malate dehydrogenase (MDH), malic enzyme (ME), glucose 6-phosphate dehydrogenase (G6PD), lactate dehydrogenase (LDH), and superoxide dismutase (SOD) isoenzyme analysis following starch-gel electrophoresis, and the isoenzyme patterns were compared with those obtained from other species of trichurids. MDH, ME, G6PD, LDH, and SOD isoenzyme patterns were identical for T. suis from both hosts. MDH isoenzyme patterns were characterized by the presence of one cathodic isoenzyme. ME, G6PD, and LDH isoenzyme patterns indicated the presence of three phenotypes, whereas the SOD isoenzyme pattern showed only one phenotype characterized by the existence of two (anodic and cathodic) bands. Different LDH and SOD isoenzyme patterns observed for T. suis, T. ovis, and T. skrjabini confirm once more that isoenzyme patterns have potential as a diagnostic tool for differentiation of different species of Trichuris.

A test of alternative models of diversification in tropical rainforests: Ecological gradients vs. rainforest refugia

PubMed Central

Schneider, Christopher J.; Smith, Thomas B.; Larison, Brenda; Moritz, Craig

1999-01-01

Comparison of mitochondrial and morphological divergence in eight populations of a widespread leaf-litter skink is used to determine the relative importance of geographic isolation and natural selection in generating phenotypic diversity in the Wet Tropics Rainforest region of Australia. The populations occur in two geographically isolated regions, and within each region, in two different habitats (closed rainforest and tall open forest) that span a well characterized ecological gradient. Morphological differences among ancient geographic isolates (separated for several million years, judging by their mitochondrial DNA sequence divergence) were slight, but morphological and life history differences among habitats were large and occurred despite moderate to high levels of mitochondrial gene flow. A field experiment identified avian predation as one potential agent of natural selection. These results indicate that natural selection operating across ecological gradients can be more important than geographic isolation in similar habitats in generating phenotypic diversity. In addition, our results indicate that selection is sufficiently strong to overcome the homogenizing effects of gene flow, a necessary first step toward speciation in continuously distributed populations. Because ecological gradients may be a source of evolutionary novelty, and perhaps new species, their conservation warrants greater attention. This is particularly true in tropical regions, where most reserves do not include ecological gradients and transitional habitats. PMID:10570165

Biological dinitrogen fixation by selected soil cyanobacteria as affected by strain origin, morphotype, and light conditions.

PubMed

Hrčková, K; Simek, M; Hrouzek, P; Lukešová, A

2010-09-01

The potential for N(2) fixation by heterocystous cyanobacteria isolated from soils of different geographical areas was determined as nitrogenase activity (NA) using the acetylene reduction assay. Morphology of cyanobacteria had the largest influence on NA determined under light conditions. NA was generally higher in species lacking thick slime sheaths. The highest value (1446 nmol/h C(2)H(4) per g fresh biomass) was found in the strain of branched cyanobacterium Hassalia (A Has1) from the polar region. A quadratic relationship between NA and biomass was detected in the Tolypothrix group under light conditions. The decline of NA in dark relative to light conditions ranged from 37 to 100 % and differed among strains from distinct geographical areas. Unlike the NA of temperate and tropical strains, whose decline in dark relative to light was 24 and 17 %, respectively, the NA of polar strains declined to 1 % in the dark. This difference was explained by adaptation to different light conditions in temperate, tropical, and polar habitats. NA was not related to the frequency of heterocysts in strains of the colony-forming cyanobacterium Nostoc. Colony morphology and life cycle are therefore more important for NA then heterocyst frequency. NA values probably reflect the environmental conditions where the cyanobacterium was isolated and the physiological and morphological state of the strain.

Morphological characteristics and genetic diversity of Burmese long-tailed Macaques (Macaca fascicularis aurea).

PubMed

Bunlungsup, Srichan; Imai, Hiroo; Hamada, Yuzuru; Gumert, Michael D; San, Aye Mi; Malaivijitnond, Suchinda

2015-12-15

Macaca fascicularis aurea (Mfa) is the only macaque which has been recorded to use stone tools to access encased foods. They live in close contact with M. fascicularis fascicularis (Mff) in southwestern Thailand and the hybrids were reported [Fooden, 1995]. Although Mff and Mfa can be seen in the same habitat types, tool-use behavior has never been reported in Mff. Thus, comparing the morphological characteristics and genetics between Mfa and Mff should help elucidate not only the morphological differences and genetic divergence between these subspecies but also potentially the relationship between genetics and their tool use behavior. We surveyed Mfa and Mff in Myanmar and Thailand, ranging from 16° 58' to 7° 12' N. Fecal or blood samples were collected from eight, five, and four populations of Mfa, Mff, and Mff × Mfa morphological hybrids along with three individuals of captive Chinese M. mulatta (Mm), respectively, for mtDNA and Y-chromosome (TSPY and SRY genes) DNA sequence analyses. In addition, eight populations were captured and measured for 38 somatometric dimensions. Comparison of the somatic measurements revealed that Mfa had a statistically significantly shorter tail than Mff (P < 0.05). Based on the mtDNA sequences, Mfa was separated from the Mm/Mff clade. Within the Mfa clade, the mainland Myanmar population was separate from the Mergui Archipelago and Thailand Andaman seacoast populations. All the morphological hybrids had the Mff mtDNA haplotype. Based on the Y-chromosome sequences, the three major clades of Mm/Indochinese Mff, Sundaic Mff, and Mfa were constructed. The hybrid populations grouped either with the Mm/Indochinese Mff or with the Mfa. Regarding the genetic analysis, one subspecies hybrid population in Thailand (KRI) elicited tool use behavior, thus the potential role of genetics in tool use behavior is raised in addition to the environmental force, morphological suitability, and cognitive capability. Am. J. Primatol. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Morphological Encoding in German Children's Language Production: Evidence from Event-Related Brain Potentials

ERIC Educational Resources Information Center

Jessen, Anna; Fleischhauer, Elisabeth; Clahsen, Harald

2017-01-01

This study reports developmental changes in morphological encoding across late childhood. We examined event-related brain potentials (ERPs) during the silent production of regularly vs. irregularly inflected verb forms (viz. "-t" vs. "-n" participles of German) in groups of eight- to ten-year-olds, eleven- to…

Interactive robots in experimental biology.

PubMed

Krause, Jens; Winfield, Alan F T; Deneubourg, Jean-Louis

2011-07-01

Interactive robots have the potential to revolutionise the study of social behaviour because they provide several methodological advances. In interactions with live animals, the behaviour of robots can be standardised, morphology and behaviour can be decoupled (so that different morphologies and behavioural strategies can be combined), behaviour can be manipulated in complex interaction sequences and models of behaviour can be embodied by the robot and thereby be tested. Furthermore, robots can be used as demonstrators in experiments on social learning. As we discuss here, the opportunities that robots create for new experimental approaches have far-reaching consequences for research in fields such as mate choice, cooperation, social learning, personality studies and collective behaviour. Copyright © 2011 Elsevier Ltd. All rights reserved.

Photocatalytic and antibacterial activity of cadmium sulphide/zinc oxide nanocomposite with varied morphology.

PubMed

Jana, T K; Maji, S K; Pal, A; Maiti, R P; Dolai, T K; Chatterjee, K

2016-10-15

Nanocomposites with multifunctional application prospects have already dragged accelerating interests of materials scientists. Here we present CdS/ZnO nanocomposites with different morphology engineering the precursor molar ratio in a facile wet chemical synthesis route. The materials were structurally and morphologically characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray analysis (EDX) and high-resolution transmission electron microscopy (HRTEM). The growth mechanism of the composite structure with varying molar ratio is delineated with oriented attachment self assemble techniques. Photocatalytic activity of CdS/ZnO nanocomposites with varying morphology were explored for the degradation of rhodamine B (RhB) dye in presence of visible light irradiation and the results reveal that the best catalytic performance arises in CdS/ZnO composite with 1: 1 ratio. The antibacterial efficiency of all nanocomposites were investigated on Escherichia coli, Staphylococcus aureus and Klebsiella pneumonia without light irradiation. Antibacterial activity of CdS/ZnO nanocomposites were studied using the bacteriological test-well diffusion agar method and results showed significant antibacterial activity in CdS/ZnO composite with 1:3 ratio. Overall, CdS/ZnO nanocomposites excel in different potential applications, such as visible light photocatalysis and antimicrobial activity with their tuneable structure. Copyright © 2016 Elsevier Inc. All rights reserved.

Morphological and Genetic Analysis of Four Color Morphs of Bean Leaf Beetle.

PubMed

Tiroesele, Bamphitlhi; Skoda, Steven R; Hunt, Thomas E; Lee, Donald J; Ullah, Muhammad Irfan; Molina-Ochoa, Jaime; Foster, John E

2018-03-01

Bean leaf beetle (BLB), Cerotoma trifurcata (Forster; Coleoptera: Chrysomelidae), exhibits considerable color variation but little is known about the underlying genetic structure and gene flow among color phenotypes. Genetic and morphological variation among four color phenotypes-green with spots (G+S), green without spots (G-S), red with spots (R+S) and red without spots (R-S)-were analyzed using amplified fragment length polymorphisms (AFLP) and morphometrics, respectively. AFLP generated 175 markers that showed ≥80% polymorphism. Analysis of molecular variance (AMOVA) indicated that genetic variation was greatest within phenotypes (82.6-84.0%); gene flow among the four phenotypes was relatively high (Nm = 3.82). The dendrogram and STRUCTURE analysis indicated some population divergence of G-S from the other phenotypes. Morphological parameters were similar among phenotypes except that R+S showed significant differences in weight and body-length. Canonical variables 1 and 2, based on average morphometric characters, accounted for 98% of the total variation; some divergence was indicated between G+S and R+S from each other and from the G-S/R-S BLB color morphs. The pattern of genetic variation indicated potential divergence of G-S and G+S from each other and from R-S and R+S. Although these results indicate that the four different color morphs are not genetically or reproductively isolated, there is some genetic differentiation/structure and morphological dissimilarity suggesting weak/incomplete isolation.

Does cone beam CT actually ameliorate stab wound analysis in bone?

PubMed

Gaudio, D; Di Giancamillo, M; Gibelli, D; Galassi, A; Cerutti, E; Cattaneo, C

2014-01-01

This study aims at verifying the potential of a recent radiological technology, cone beam CT (CBCT), for the reproduction of digital 3D models which may allow the user to verify the inner morphology of sharp force wounds within the bone tissue. Several sharp force wounds were produced by both single and double cutting edge weapons on cancellous and cortical bone, and then acquired by cone beam CT scan. The lesions were analysed by different software (a DICOM file viewer and reverse engineering software). Results verified the limited performances of such technology for lesions made on cortical bone, whereas on cancellous bone reliable models were obtained, and the precise morphology within the bone tissues was visible. On the basis of such results, a method for differential diagnosis between cutmarks by sharp tools with a single and two cutting edges can be proposed. On the other hand, the metrical computerised analysis of lesions highlights a clear increase of error range for measurements under 3 mm. Metric data taken by different operators shows a strong dispersion (% relative standard deviation). This pilot study shows that the use of CBCT technology can improve the investigation of morphological stab wounds on cancellous bone. Conversely metric analysis of the lesions as well as morphological analysis of wound dimension under 3 mm do not seem to be reliable.

Transmitter release in the neuromuscular synapse of the protein kinase C theta-deficient adult mouse.

PubMed

Besalduch, Núria; Santafé, Manel M; Garcia, Neus; Gonzalez, Carmen; Tomás, Marta; Tomás, Josep; Lanuza, Maria A

2011-04-01

We studied structural and functional features of the neuromuscular junction in adult mice (P30) genetically deficient in the protein kinase C (PKC) theta isoform. Confocal and electron microscopy shows that there are no differences in the general morphology of the endplates between PKC theta-deficient and wild-type (WT) mice. Specifically, there is no difference in the density of the synaptic vesicles. However, the myelin sheath is not as thick in the intramuscular nerve fibers of the PKC theta-deficient mice. We found a significant reduction in the size of evoked endplate potentials and in the frequency of spontaneous, asynchronous, miniature endplate potentials in the PKC theta-deficient neuromuscular preparations in comparison with the WT, but the mean amplitude of the spontaneous potentials is not different. These changes indicate that PKC theta has a presynaptic role in the function of adult neuromuscular synapses. Copyright © 2010 Wiley-Liss, Inc.

Retinal ganglion cells in the eastern newt Notophthalmus viridescens: topography, morphology, and diversity.

PubMed

Pushchin, Igor I; Karetin, Yuriy A

2009-10-20

The topography and morphology of retinal ganglion cells (RGCs) in the eastern newt were studied. Cells were retrogradely labeled with tetramethylrhodamine-conjugated dextran amines or horseradish peroxidase and examined in retinal wholemounts. Their total number was 18,025 +/- 3,602 (mean +/- SEM). The spatial density of RGCs varied from 2,100 cells/mm(2) in the retinal periphery to 4,500 cells/mm(2) in the dorsotemporal retina. No prominent retinal specializations were found. The spatial resolution estimated from the spatial density of RGCs varied from 1.4 cycles per degree in the periphery to 1.95 cycles per degree in the region of the peak RGC density. A sample of 68 cells was camera lucida drawn and subjected to quantitative analysis. A total of 21 parameters related to RGC morphology and stratification in the retina were estimated. Partitionings obtained by using different clustering algorithms combined with automatic variable weighting and dimensionality reduction techniques were compared, and an effective solution was found by using silhouette analysis. A total of seven clusters were identified and associated with potential cell types. Kruskal-Wallis ANOVA-on-Ranks with post hoc Mann-Whitney U tests showed significant pairwise between-cluster differences in one or more of the clustering variables. The average silhouette values of the clusters were reasonably high, ranging from 0.52 to 0.79. Cells assigned to the same cluster displayed similar morphology and stratification in the retina. The advantages and limitations of the methodology adopted are discussed. The present classification is compared with known morphological and physiological RGC classifications in other salamanders.

Preparation of zein nanoparticles by using solution-enhanced dispersion with supercritical CO2 and elucidation with computational fluid dynamics

PubMed Central

Li, Sining; Zhao, Yaping

2017-01-01

Nanoparticles have attracted more and more attention in the medicinal field. Zein is a biomacromolecule and can be used as a carrier for delivering active ingredients to prepare controlled release drugs. In this article, we presented the preparation of zein nanoparticles by solution-enhanced dispersion by supercritical CO2 (SEDS) approach. Scanning electron microscopy and transmission electron microscopy were applied to characterize the size and morphology of the obtained particles. The nozzle structure and the CO2 flow rate greatly affected the morphology and the size of the particles. The size of zein was able to be reduced to 50–350 nm according to the different conditions. The morphologies of the resultant zein were either sphere or the filament network consisted of nanoparticles. The influence of the nozzle structure and the CO2 flow rate on the velocity field was elucidated by using computational fluid dynamics. The nozzle structure and the CO2 flow rate greatly affected the distribution of the velocity field. However, a similar velocity field could also be obtained when the nozzle structure or the CO2 flow rate, or both were different. Therefore, the influence of the nozzle structure and the CO2 flow rate on the size and morphology of the particles, can boil down to the velocity field. The results demonstrated that the velocity field can be a potential criterion for producing nanoparticles with controllable morphology and size, which is useful to scale-up the SEDS process. PMID:28496324

Liquid-phase characterization of molecular interactions in polyunsaturated and n-fatty acid methyl esters by (1)H low-field nuclear magnetic resonance.

PubMed

Meiri, Nitzan; Berman, Paula; Colnago, Luiz Alberto; Moraes, Tiago Bueno; Linder, Charles; Wiesman, Zeev

2015-01-01

To identify and develop the best renewable and low carbon footprint biodiesel substitutes for petroleum diesel, the properties of different biodiesel candidates should be studied and characterized with respect to molecular structures versus biodiesel liquid property relationships. In our previous paper, (1)H low-field nuclear magnetic resonance (LF-NMR) relaxometry was investigated as a tool for studying the liquid-phase molecular packing interactions and morphology of fatty acid methyl esters (FAMEs). The technological potential was demonstrated with oleic acid and methyl oleate standards having similar alkyl chains but different head groups. In the present work, molecular organization versus segmental and translational movements of FAMEs in their pure liquid phase, with different alkyl chain lengths (10-20 carbons) and degrees of unsaturation (0-3 double bonds), were studied with (1)H LF-NMR relaxometry and X-ray, (1)H LF-NMR diffusiometry, and (13)C high-field NMR. Based on density values and X-ray measurements, it was proposed that FAMEs possess a liquid crystal-like order above their melting point, consisting of random liquid crystal aggregates with void spaces between them, whose morphological properties depend on chain length and degree of unsaturation. FAMEs were also found to exhibit different degrees of rotational and translational motions, which were rationalized by chain organization within the clusters, and the degree and type of molecular interactions and temperature effects. At equivalent fixed temperature differences from melting point, saturated FAME molecules were found to have similar translational motion regardless of chain length, expressed by viscosity, self-diffusion coefficients, and spin-spin (T 2) (1)H LF-NMR. T 2 distributions suggest increased alkyl chain rigidity, and reduced temperature response of the peaks' relative contribution with increasing unsaturation is a direct result of the alkyl chain's morphological packing and molecular interactions. Both the peaks' assignments for T 2 distributions of FAMEs and the model for their liquid crystal-like morphology in the liquid phase were confirmed. The study of morphological structures within liquids and their response to temperature changes by (1)H LF-NMR has a high value in the field of biodiesel and other research and applied disciplines in numerous physicochemical- and organizational-based properties, processes, and mechanisms of alkyl chains, molecular interactions, and morphologies.

Surface-potential undulation of Alq3 thin films prepared on ITO, Au, and n-Si.

PubMed

Ozasa, Kazunari; Ito, Hiromi; Maeda, Mizuo; Hara, Masahiko

2012-01-01

The surface potential (SP) morphology on thin films of tris(8-hydroxyquinolinato) aluminum (Alq3) was investigated with Kelvin probe force microscopy. Thin Alq3 films of 100 nm were prepared on ITO/glass substrates, Au/mica substrates, and n-Si substrates. Cloud-like morphologies of the SP undulation with 200-400 nm in lateral size were observed for all three types of the substrates. New larger peaks were observed in the cloud-like morphologies when the surfaces were exposed shortly to a light, while the SP average was reduced monotonically. The nonuniform distribution of charged traps and mobility was deduced from the SP undulation morphology and its photoexposure dependences.

Effect of Cu Alloying on S Poisoning of Ni Surfaces and Nanoparticle Morphologies Using Ab-Initio Thermodynamics Calculations.

PubMed

Kim, Ji-Su; Kim, Byung-Kook; Kim, Yeong-Cheol

2015-10-01

We investigated the effect of Cu alloying on S poisoning of Ni surfaces and nanoparticle morphologies using ab-initio thermodynamics calculations. Based on the Cu segregation energy and the S adsorption energy, the surface energy and nanoparticle morphology of pure Ni, pure Cu, and NiCu alloys were evaluated as functions of the chemical potential of S and the surface orientations of (100), (110), and (111). The constructed nanoparticle morphology was varied as a function of chemical potential of S. We find that the Cu added to Ni for NiCu alloys is strongly segregated into the top surface, and increases the S tolerance of the NiCu nanoparticles.

Hunting behaviour and breeding performance of northern goshawks Accipiter gentilis, in relation to resource availability, sex, age and morphology

NASA Astrophysics Data System (ADS)

Penteriani, Vincenzo; Rutz, Christian; Kenward, Robert

2013-10-01

Animal territories that differ in the availability of food resources will require (all other things being equal) different levels of effort for successful reproduction. As a consequence, breeding performance may become most strongly dependent on factors that affect individual foraging where resources are poor. We investigated potential links between foraging behaviour, reproductive performance and morphology in a goshawk Accipiter gentilis population, which experienced markedly different resource levels in two different parts of the study area (rabbit-rich vs. rabbit-poor areas). Our analyses revealed (1) that rabbit abundance positively affected male reproductive output; (2) that age, size and rabbit abundance (during winter) positively affected different components of female reproductive output; (3) that foraging movements were inversely affected by rabbit abundance for both sexes (for females, this may mainly have reflected poor provisioning by males in the rabbit-poor area); (4) that younger breeders (both in males and females) tended to move over larger distances than older individuals (which may have reflected both a lack of hunting experience and mate searching); and (5) that male body size (wing length) showed some covariation with resource conditions (suggesting possible adaptations to hunting agile avian prey in the rabbit-poor area). Although we are unable to establish firm causal relationships with our observational data set, our results provide an example of how territory quality (here, food abundance) and individual features (here, age and morphology) may combine to shape a predator's foraging behaviour and, ultimately, its breeding performance.

Study on structure and morphology (Boehmeria nivea) in the irregular and regular parts of the fiber after biodegumming

NASA Astrophysics Data System (ADS)

Wulandari, A. P.; Septarini, D.; Zainuddin, A.

2017-05-01

Ramie is a natural fiber that is very potential to be developed in Indonesia. Decorticated-fiber which has been known as china grass produce different structures irregular part but shows a long straight section in the middle. This study aims to determine differences in chemical components, morphology and microstructure of two different parties after biodegumming process. China grass has been processed to remove gum using pectinolytic fungus. The microstructure of the treated was further tested by Fourier Transform InfraRed (FTIR), X-Ray Diffraction (XRD), and Scanning Electron Microscope (SEM). The FTIR study indicated that during the biodegumming process, chemical bonding of non-cellulose components most removed by the activity of pectinase from the fungus. XRD analysis reflects an increase in the crystallinity of the fiber after biodegumming. Scanning electron microscopy (SEM) was used to confirm a reduction in the size of the fiber after biodegumming either in the irregular and regular part of the fiber after biodegumming.

Electron Transfer Strategies Regulate Carbonate Mineral and Micropore Formation.

PubMed

Zeng, Zhirui; Tice, Michael M

2018-01-01

Some microbial carbonates are robust biosignatures due to their distinct morphologies and compositions. However, whether carbonates induced by microbial iron reduction have such features is unknown. Iron-reducing bacteria use various strategies to transfer electrons to iron oxide minerals (e.g., membrane-bound enzymes, soluble electron shuttles, nanowires, as well as different mechanisms for moving over or attaching to mineral surfaces). This diversity has the potential to create mineral biosignatures through manipulating the microenvironments in which carbonate precipitation occurs. We used Shewanella oneidensis MR-1, Geothrix fermentans, and Geobacter metallireducens GS-15, representing three different strategies, to reduce solid ferric hydroxide in order to evaluate their influence on carbonate and micropore formation (micro-size porosity in mineral rocks). Our results indicate that electron transfer strategies determined the morphology (rhombohedral, spherical, or long-chained) of precipitated calcium-rich siderite by controlling the level of carbonate saturation and the location of carbonate formation. Remarkably, electron transfer strategies also produced distinctive cell-shaped micropores in both carbonate and hydroxide minerals, thus producing suites of features that could potentially serve as biosignatures recording information about the sizes, shapes, and physiologies of iron-reducing organisms. Key Words: Microbial iron reduction-Micropore-Electron transfer strategies-Microbial carbonate. Astrobiology 18, 28-36.

Unilateral hearing during development: hemispheric specificity in plastic reorganizations

PubMed Central

Kral, Andrej; Heid, Silvia; Hubka, Peter; Tillein, Jochen

2013-01-01

The present study investigates the hemispheric contributions of neuronal reorganization following early single-sided hearing (unilateral deafness). The experiments were performed on ten cats from our colony of deaf white cats. Two were identified in early hearing screening as unilaterally congenitally deaf. The remaining eight were bilaterally congenitally deaf, unilaterally implanted at different ages with a cochlear implant. Implanted animals were chronically stimulated using a single-channel portable signal processor for two to five months. Microelectrode recordings were performed at the primary auditory cortex under stimulation at the hearing and deaf ear with bilateral cochlear implants. Local field potentials (LFPs) were compared at the cortex ipsilateral and contralateral to the hearing ear. The focus of the study was on the morphology and the onset latency of the LFPs. With respect to morphology of LFPs, pronounced hemisphere-specific effects were observed. Morphology of amplitude-normalized LFPs for stimulation of the deaf and the hearing ear was similar for responses recorded at the same hemisphere. However, when comparisons were performed between the hemispheres, the morphology was more dissimilar even though the same ear was stimulated. This demonstrates hemispheric specificity of some cortical adaptations irrespective of the ear stimulated. The results suggest a specific adaptation process at the hemisphere ipsilateral to the hearing ear, involving specific (down-regulated inhibitory) mechanisms not found in the contralateral hemisphere. Finally, onset latencies revealed that the sensitive period for the cortex ipsilateral to the hearing ear is shorter than that for the contralateral cortex. Unilateral hearing experience leads to a functionally-asymmetric brain with different neuronal reorganizations and different sensitive periods involved. PMID:24348345

Unilateral hearing during development: hemispheric specificity in plastic reorganizations.

PubMed

Kral, Andrej; Heid, Silvia; Hubka, Peter; Tillein, Jochen

2013-01-01

The present study investigates the hemispheric contributions of neuronal reorganization following early single-sided hearing (unilateral deafness). The experiments were performed on ten cats from our colony of deaf white cats. Two were identified in early hearing screening as unilaterally congenitally deaf. The remaining eight were bilaterally congenitally deaf, unilaterally implanted at different ages with a cochlear implant. Implanted animals were chronically stimulated using a single-channel portable signal processor for two to five months. Microelectrode recordings were performed at the primary auditory cortex under stimulation at the hearing and deaf ear with bilateral cochlear implants. Local field potentials (LFPs) were compared at the cortex ipsilateral and contralateral to the hearing ear. The focus of the study was on the morphology and the onset latency of the LFPs. With respect to morphology of LFPs, pronounced hemisphere-specific effects were observed. Morphology of amplitude-normalized LFPs for stimulation of the deaf and the hearing ear was similar for responses recorded at the same hemisphere. However, when comparisons were performed between the hemispheres, the morphology was more dissimilar even though the same ear was stimulated. This demonstrates hemispheric specificity of some cortical adaptations irrespective of the ear stimulated. The results suggest a specific adaptation process at the hemisphere ipsilateral to the hearing ear, involving specific (down-regulated inhibitory) mechanisms not found in the contralateral hemisphere. Finally, onset latencies revealed that the sensitive period for the cortex ipsilateral to the hearing ear is shorter than that for the contralateral cortex. Unilateral hearing experience leads to a functionally-asymmetric brain with different neuronal reorganizations and different sensitive periods involved.

Flagellar Sensillar Equipment of Two Morphologically Closely Related Aphid Hyperparasitoids (Hymenoptera: Figitidae: Alloxysta)

PubMed Central

Polidori, Carlo; Freitas-Cerqueira, Amanda; Pujade-Villar, Juli; Oliva, Francesc; Ferrer-Suay, Mar

2016-01-01

The antennal sensillar equipment in the parasitic wasp family Figitidae was analyzed to date only in few species, despite some are associated with crop pests and can have an economic importance. It is the case of the genus Alloxysta, which includes hyperparasitoids of aphids which can potentially reduce effectiveness of primary pest parasitoids. Here we analyzed, through scanning electron microscopy, the diversity, morphology, and distribution of the antennal sensilla in males and females of Alloxysta consobrina (Zetterstedt) and Alloxysta victrix (Westwood), two species with overall very similar morphology. In both species, antennae are filiform and cylindrical, and flagellum was longer in A. victrix. Eight sensillar types have been recognized: four types of sensilla trichoidea (ST-A, ST-B, ST-C, ST-D), sensilla coeloconica, sensilla placoidea, sensilla campaniformia, and sensilla basiconica. ST-A, ST-B, ST-C, and sensilla placoidea were the most abundant types on the antennae and often increased in number and decreased in size toward the tip of antenna. The two species seem to have several differences in their sensillar equipment, possibly in accordance with the different degree of host range. On the other hand, sexual dimorphism is probably due to the different stimuli that have to be correctly processed. The comparison with the other species of Figitidae studied by far showed, at subfamily-level, that variability in sensillar equipment and phylogeny do not agree. This suggests a complex series of morphological changes during evolution of this group. The taxonomic sample should be thus substantially enlarged to disclose possible trends in sensillar equipment evolution in the family. PMID:26810561

Free Global Dsm Assessment on Large Scale Areas Exploiting the Potentialities of the Innovative Google Earth Engine Platform

NASA Astrophysics Data System (ADS)

Nascetti, A.; Di Rita, M.; Ravanelli, R.; Amicuzi, M.; Esposito, S.; Crespi, M.

2017-05-01

The high-performance cloud-computing platform Google Earth Engine has been developed for global-scale analysis based on the Earth observation data. In particular, in this work, the geometric accuracy of the two most used nearly-global free DSMs (SRTM and ASTER) has been evaluated on the territories of four American States (Colorado, Michigan, Nevada, Utah) and one Italian Region (Trentino Alto- Adige, Northern Italy) exploiting the potentiality of this platform. These are large areas characterized by different terrain morphology, land covers and slopes. The assessment has been performed using two different reference DSMs: the USGS National Elevation Dataset (NED) and a LiDAR acquisition. The DSMs accuracy has been evaluated through computation of standard statistic parameters, both at global scale (considering the whole State/Region) and in function of the terrain morphology using several slope classes. The geometric accuracy in terms of Standard deviation and NMAD, for SRTM range from 2-3 meters in the first slope class to about 45 meters in the last one, whereas for ASTER, the values range from 5-6 to 30 meters. In general, the performed analysis shows a better accuracy for the SRTM in the flat areas whereas the ASTER GDEM is more reliable in the steep areas, where the slopes increase. These preliminary results highlight the GEE potentialities to perform DSM assessment on a global scale.

Screening of antagonistic bacteria isolated from Amorphophallus konjac rhizosphere soil

NASA Astrophysics Data System (ADS)

Lin, Tianxing; Gong, Mingfu; Guan, Qinlan; Huang, Ying; Qin, Fang

2018-04-01

Bacteria lived in Amorphaphallus konjac rhizosphere soil have the potential ability of antagonistic bacterial pathogen activity against to Erwinia carotovora subsp carotovora (Ecc). The paper was to study and analyze all strains of 18 bacteria isolated from A. konjac rhizosphere soil with strong antagonistic effect against to Ecc and to identify antagonistic bacteria with morphology, physiology and biochemistry characteristic. The antagonistic bacterial pathogen activity of different bacterial strains were significantly different. Five of 18 strains isolated from A. konjac rhizosphere soil, including AKSB03, AKSB05, AKSB08, AKSB13 and AKSB16 was screened with antagonistic wider more than 15 mm in first screening test. Strain AKSB08 and strain AKSB16 had a strong antagonism activity for Ecc with antagonistic wider more than 20 mm in second screening test. Strain AKSB08 and strain AKSB16 belonged to Bacillus with morphology, physiology and biochemistry characteristic.

Effect of Ultrasonic on Copper Electroplating from the Non-Cyanide Alkaline Baths

NASA Astrophysics Data System (ADS)

Li, Minggang; Hu, Shuangshuang; Yang, Yejiong; Xu, Shuhan; Zhao, Xixi; Wei, Guoying

2014-06-01

Effects of the different ultrasonic powers on copper electrodeposition from non-cyanide alkaline baths by using pyrophosphate as complexing agent were investigated by different electrochemical methods. Cyclic voltammetry and current transient measurements were used to characterize the nucleation and growth mechanism. It is very obvious that the reduction potential moves to more positive one as the ultrasonic power increases. The quartz crystal microbalance (QCM) and chronoamperometric method were used to study the relationship between the mass change and the deposition time. It was found that the current efficiency of electrolyte under 0, 60, 80 and 100 W is 91.95%, 92.14%, 89.25% and 96.11%, respectively measured by QCM measurements. The surface morphology of the electrodeposited Cu films is analyzed by scanning electron microscopy (SEM). The morphology of copper films electrodeposited under the power of 60 W and 80 W presents a compact surface and the grains are fine and uniform.

The utilization of ERTS-1-generated photographs in the evaluation of the Iranian playas as potential locations for economic and engineering development. [hydrology and morphology of playa soils

NASA Technical Reports Server (NTRS)

Krinsley, D. B. (Principal Investigator)

1973-01-01

The author has identified the following significant results. Hydrologic inventories, throughout the year, were made in interior basins that have not been measured previously because of their inaccessibility. Interior basins during the last ERTS-1 year (August 1972 to August 1973) had driest ground conditions in late September 1972 and had wettest ground conditions from March through May 1973, depending upon location. Bearing strengths of playa soils can be inferred from the changing hydrologic conditions through the seasons as recorded by ERTS-1, with prior ground control. Slight differences in salt-crust morphology and in moisture contest of playa soils can be greatly enhanced by rationing and stretching techniques. Differences in water area and silt content can be enhanced by using a three-stage photographic masking technique employing bands 4, 5, and 7.

Selection on an antagonistic behavioral trait can drive rapid genital coevolution in the burying beetle, Nicrophorus vespilloides.

PubMed

Hopwood, Paul E; Head, Megan L; Jordan, Eleanor J; Carter, Mauricio J; Davey, Emma; Moore, Allen J; Royle, Nick J

2016-06-01

Male and female genital morphology varies widely across many taxa, and even among populations. Disentangling potential sources of selection on genital morphology is problematic because each sex is predicted to respond to adaptations in the other due to reproductive conflicts of interest. To test how variation in this sexual conflict trait relates to variation in genital morphology we used our previously developed artificial selection lines for high and low repeated mating rates. We selected for high and low repeated mating rates using monogamous pairings to eliminate contemporaneous female choice and male-male competition. Male and female genital shape responded rapidly to selection on repeated mating rate. High and low mating rate lines diverged from control lines after only 10 generations of selection. We also detected significant patterns of male and female genital shape coevolution among selection regimes. We argue that because our selection lines differ in sexual conflict, these results support the hypothesis that sexually antagonistic coevolution can drive the rapid divergence of genital morphology. The greatest divergence in morphology corresponded with lines in which the resolution of sexual conflict over mating rate was biased in favor of male interests. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Morphological observation and analysis using automated image cytometry for the comparison of trypan blue and fluorescence-based viability detection method.

PubMed

Chan, Leo Li-Ying; Kuksin, Dmitry; Laverty, Daniel J; Saldi, Stephanie; Qiu, Jean

2015-05-01

The ability to accurately determine cell viability is essential to performing a well-controlled biological experiment. Typical experiments range from standard cell culturing to advanced cell-based assays that may require cell viability measurement for downstream experiments. The traditional cell viability measurement method has been the trypan blue (TB) exclusion assay. However, since the introduction of fluorescence-based dyes for cell viability measurement using flow or image-based cytometry systems, there have been numerous publications comparing the two detection methods. Although previous studies have shown discrepancies between TB exclusion and fluorescence-based viability measurements, image-based morphological analysis was not performed in order to examine the viability discrepancies. In this work, we compared TB exclusion and fluorescence-based viability detection methods using image cytometry to observe morphological changes due to the effect of TB on dead cells. Imaging results showed that as the viability of a naturally-dying Jurkat cell sample decreased below 70 %, many TB-stained cells began to exhibit non-uniform morphological characteristics. Dead cells with these characteristics may be difficult to count under light microscopy, thus generating an artificially higher viability measurement compared to fluorescence-based method. These morphological observations can potentially explain the differences in viability measurement between the two methods.

How and why to achieve greater objectivity in taxonomy, exemplified by a fossil ostracod (Amplocypris abscissa) from the Miocene Lake Pannon

PubMed Central

Danielopol, Dan L.; Gross, Martin; Harzhauser, Mathias; Minati, Klaus; Piller, Werner E.

2017-01-01

A project on fossil ostracods from Hennersdorf (Vienna Basin, Middle Pannonian “E” stage) documents the non-marine ostracod Amplocypris abscissa (Reuss 1850) as a polymorphic taxon. The high morphological variability of the valves belonging to this species and its geographic distribution in the Lake Pannon point to a widely spread fossil taxon. This traditional view emerges from the fact that A. abscissa displays few homologous “landmarks” (morphological reference points) which makes it difficult to compare morphotypes within and among populations. The present contribution offers arguments for the need of objective criteria when describing ostracods with few visible morphological traits. It is demonstrated that using a composite algorithmic approach which combines information implemented in the computer programme MORPHOMATICA for different variables, measured on interval and ratio scales, is able to define morphological traits objectively. The data analysed with multivariate statistics are further used for diagnostic profiles of clearly delineated morphotypes. The potential taxonomic value of three morphotypes here identified for Amplocypris abscissa is discussed. It is argued that this taxon represents a phylogenetic lineage within which a cluster of species with discrete morphological traits exists. Finally, it is proposed to apply similar algorithms for the necessary revision of the whole group of Amplocypris species from Lake Pannon. PMID:28090196

Morphological and biochemical variations in the gills of 12 aquatic air-breathing anabantoid fish.

PubMed

Huang, Chun-Yen; Lin, Chung-Ping; Lin, Hui-Chen

2011-01-01

All fish species in the Anabantoidei suborder are aquatic air-breathing fish. These species have an accessory air-breathing organ, called the labyrinth organ, in the branchial cavity and can engulf air at the surface of the water to assist in gas exchange. It is therefore necessary to examine the extent of gill modification among anabantoid fish species and the potential trade-offs in their function. The experimental hypothesis that we aimed to test is whether anabantoid fishes have both morphological and functional variations in the gills among different species. We examined the gills of 12 species from three families and nine genera of Anabantoidei. Though the sizes of the fourth gill arch in three species of Trichogaster were reduced significantly, not all anabantoid species had morphological and functional variations in the gills. In these three species, the specific enzyme activity and relative protein abundance of Na(+)/K(+)-ATPase were significantly higher in the anterior gills as compared with the posterior gills and the labyrinth organ. The relative abundance of cytosolic carbonic anhydrase, an indicator of gas exchange, was found to be highest in the labyrinth organ. The phylogenetic distribution of the fourth gill's morphological differentiation suggests that these variations are lineage specific, which may imply a phylogenetic influence on gill morphology in anabantoid species.

Statistical analysis and data mining of digital reconstructions of dendritic morphologies.

PubMed

Polavaram, Sridevi; Gillette, Todd A; Parekh, Ruchi; Ascoli, Giorgio A

2014-01-01

Neuronal morphology is diverse among animal species, developmental stages, brain regions, and cell types. The geometry of individual neurons also varies substantially even within the same cell class. Moreover, specific histological, imaging, and reconstruction methodologies can differentially affect morphometric measures. The quantitative characterization of neuronal arbors is necessary for in-depth understanding of the structure-function relationship in nervous systems. The large collection of community-contributed digitally reconstructed neurons available at NeuroMorpho.Org constitutes a "big data" research opportunity for neuroscience discovery beyond the approaches typically pursued in single laboratories. To illustrate these potential and related challenges, we present a database-wide statistical analysis of dendritic arbors enabling the quantification of major morphological similarities and differences across broadly adopted metadata categories. Furthermore, we adopt a complementary unsupervised approach based on clustering and dimensionality reduction to identify the main morphological parameters leading to the most statistically informative structural classification. We find that specific combinations of measures related to branching density, overall size, tortuosity, bifurcation angles, arbor flatness, and topological asymmetry can capture anatomically and functionally relevant features of dendritic trees. The reported results only represent a small fraction of the relationships available for data exploration and hypothesis testing enabled by sharing of digital morphological reconstructions.

The pathogenicity of Beauveria bassiana: what happens after an endophytic phase in plants?

PubMed

Akello, J; Dubois, T; Coyne, D; Kyamanywa, S

2010-01-01

The banana weevil Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) is a serious constraint to banana (Musa spp.) production throughout the world. The entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales) offers a potential weevil management option, but conventional delivery mechanisms have limited its success. As an endophyte, however, B. bassiana can be efficiently delivered to banana planting materials for the potential management of C. sordidus. However, entomopathogens can change morphology and efficacy against their target host when successively sub-cultured on artificial media or when exposed to certain physical and chemical environmental conditions. Whether such changes occur in B. bassiana after an endophytic phase inside a banana plant remains unknown. The primary aim of our study was to evaluate the viability, growth, sporulation and pathogenicity of endophytic B. bassiana. To attain this, two sets of experiments, namely morphological characterization and larval bioassays, were conducted under laboratory conditions. In these experiments, growth and pathogenicity of the wild-type B. bassiana strain G41, obtained originally from banana farms, was compared with the endophytic B. bassiana strain G41, re-isolated from the rhizome of B. bassiana-inoculated banana plants at one month post-inoculation. Morphological characterization, conidial germination, colony growth and sporulation rate was assessed on SDAY media while pathogenicity was determined 15 days after immersing the larvae of C. sordidus in different conidial doses. No differences were observed in colony appearance and growth rate between the endophytic and wild-type strain. Percentage conidial germination for the endophytic strain (91.4-94.0%) was higher than for the wild-type (86.6-89.7%). LD50 equated 1.76 x 10(5) and 0.71 x 10(5) conidia/ml for the wild-type and endophytic B. bassiana strains, respectively, but did not differ between strains. Our study demonstrated that, after an endophytic phase inside the banana plant, B. bassiana retains it morphology and pathogenicity against the banana weevil larvae; and thus can offer protection against the damaging larvae feeding inside the rhizome.

Preliminary analysis of the potential of LANDSAT imagery to study desertification. [Xique-Xique, Brazil

NASA Technical Reports Server (NTRS)

Dejesusparada, N. (Principal Investigator); Lombardo, M. A.; Decarvalho, V. C.

1980-01-01

The use of LANDSAT imagery to define and delimit areas under process of desertification was investigated. Imagery for two different years (1973 and 1978) and two different seasons (dry and rainy seasons in 1976), were used to identify terrain morphology and vegetation cover. The analysis of LANDSAT interpretation, combined with geological and soil information obtained from published literature, allowed the identification of eleven ecological units which were classified corresponding to the degree of the Xique Xique region of Rio Sao Francisco.

A burnout prediction model based around char morphology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tao Wu; Edward Lester; Michael Cloke

Several combustion models have been developed that can make predictions about coal burnout and burnout potential. Most of these kinetic models require standard parameters such as volatile content and particle size to make a burnout prediction. This article presents a new model called the char burnout (ChB) model, which also uses detailed information about char morphology in its prediction. The input data to the model is based on information derived from two different image analysis techniques. One technique generates characterization data from real char samples, and the other predicts char types based on characterization data from image analysis of coalmore » particles. The pyrolyzed chars in this study were created in a drop tube furnace operating at 1300{sup o}C, 200 ms, and 1% oxygen. Modeling results were compared with a different carbon burnout kinetic model as well as the actual burnout data from refiring the same chars in a drop tube furnace operating at 1300{sup o}C, 5% oxygen, and residence times of 200, 400, and 600 ms. A good agreement between ChB model and experimental data indicates that the inclusion of char morphology in combustion models could well improve model predictions. 38 refs., 5 figs., 6 tabs.« less

3D printing of biomimetic microstructures for cancer cell migration.

PubMed

Huang, Tina Qing; Qu, Xin; Liu, Justin; Chen, Shaochen

2014-02-01

To understand the physical behavior and migration of cancer cells, a 3D in vitro micro-chip in hydrogel was created using 3D projection printing. The micro-chip has a honeycomb branched structure, aiming to mimic 3D vascular morphology to test, monitor, and analyze differences in the behavior of cancer cells (i.e. HeLa) vs. non-cancerous cell lines (i.e. 10 T1/2). The 3D Projection Printing system can fabricate complex structures in seconds from user-created designs. The fabricated microstructures have three different channel widths of 25, 45, and 120 microns wide to reflect a range of blood vessel diameters. HeLa and 10 T1/2 cells seeded within the micro-chip were then analyzed for morphology and cell migration speed. 10 T1/2 cells exhibited greater changes in morphology due to channel size width than HeLa cells; however, channel width had a limited effect on 10 T1/2 cell migration while HeLa cancer cell migration increased as channel width decreased. This physiologically relevant 3D cancer tissue model has the potential to be a powerful tool for future drug discoveries and cancer migration studies.

Performance, gut morphology and carcass characteristics of fattening rabbits as affected by particle size of pelleted diets.

PubMed

Tufarelli, Vincenzo; Desantis, Salvatore; Zizza, Sara; Laudadio, Vito

2010-10-01

A review of past literature revealed inconsistencies in recommended feed particle size for optimal growth and productive performance of rabbits. Changing diet formulation and subsequent processing conditions may improve pellet texture and potentially affect rabbit performance. In the current study, two isoenergetic and isonitrogenous pelleted diets were formulated, which varied in the particle size of the concentrates (2 and 8 mm, respectively). The objective was to evaluate the effect of different particle sizes of compound diets on performance, nutrient utilisation, gut morphology, and carcass characteristics of fattening Italian White breed rabbits. The finely ground diet led to a significant improvement in feed efficiency and apparent digestibility of crude protein, ether extract, crude fibre and NDF, without any negative effect on gut morphology. Furthermore, a smaller particle size of concentrates in pelleted diets improved carcass traits. Meat colour parameters showed significant differences in longissimus lumborum and biceps femoris due to dietary treatments, but in both muscles pH values 1 h and 24 h after slaughter remained unchanged. It is concluded that a finely ground pelleted diet can be used to improve growth performance of rabbits without affecting carcass parameters.

SEM Imaging for Observation of Morphological Changes in Anaemic Human Blood Cell

NASA Astrophysics Data System (ADS)

Datta, Triparna; Roychoudhury, Uttam

Scanning Electron Microscopy (SEM) is utilized to elucidate the morphological changes in anaemic human red blood cells. Haemoglobin concentration in human blood is in the range of 11.5-13.5 g/dl in healthy adults. Haemoglobin concentration in anaemic red blood is below the lower limit of normal range. Sometimes, the nature of the abnormal shape of the blood cell determines the cause of anaemia. Normally, there occurs a variation in the diameter of the red blood cell (RBC) for different types of anaemia. Increased variation of size in blood cell is termed anisocytosis (a type of anaemia) (Mohan H, Text book of pathology, New Delhi). In case of anisocytosis, diameter of cells larger than normal cell is observed. The classification of anaemia by the size of blood cell is logical, i.e. common morphological abnormality of human blood cell (Davidson's principle and practice of medicine, Publisher Churchill Livingstone, London). Cells are studied under ZEISS SEM with different magnification and applied potential of kV range. Thus the diameters of RBCs in SEM have been compared with RBCs photographed with light microscope. Anaemic cells are observed overlapped with each other with increasing diameter.

Synthesis and surface properties of submicron barium sulfate particles

NASA Astrophysics Data System (ADS)

Zhang, Ming; Zhang, Bao; Li, Xinhai; Yin, Zhoulan; Guo, Xueyi

2011-10-01

Barium sulfate particles were synthesized in the presence of EDTA at room temperature. X-ray diffractometry (XRD), Fourier transform infrared resonance (FTIR) and scanning electron microscopy (SEM) were used to characterize the structure and morphology of BaSO 4 particles. The effect of the preparation parameters on the particle size distribution and morphology was investigated. The conditional formation constants of Ba-EDTA at different pH values were calculated. The results show that the size and morphology of BaSO 4 particles can be effectively controlled by adding EDTA in the precipitation process. Among all the operation conditions, the pH value has significant effect on the particle size. The obtained barium sulfate particles are spherical and well dispersed at pH = 9-10. Zeta potentials of BaSO 4 were measured at different pH. The isoelectric point (IEP) of barium sulfate colloid appears at pH 6.92. The model of the solid-solution interface at a particle of BaSO 4 was presented. The FTIR result indicates that the surface of the prepared BaSO 4 absorbs the functional groups of EDTA, which lower the IEP of the barium sulfate particles.

A Nonsynonymous Mutation in the Transcriptional Regulator lbh Is Associated with Cichlid Craniofacial Adaptation and Neural Crest Cell Development

PubMed Central

Powder, Kara E.; Cousin, Hélène; McLinden, Gretchen P.; Craig Albertson, R.

2014-01-01

Since the time of Darwin, biologists have sought to understand the origins and maintenance of life’s diversity of form. However, the nature of the exact DNA mutations and molecular mechanisms that result in morphological differences between species remains unclear. Here, we characterize a nonsynonymous mutation in a transcriptional coactivator, limb bud and heart homolog (lbh), which is associated with adaptive variation in the lower jaw of cichlid fishes. Using both zebrafish and Xenopus, we demonstrate that lbh mediates migration of cranial neural crest cells, the cellular source of the craniofacial skeleton. A single amino acid change that is alternatively fixed in cichlids with differing facial morphologies results in discrete shifts in migration patterns of this multipotent cell type that are consistent with both embryological and adult craniofacial phenotypes. Among animals, this polymorphism in lbh represents a rare example of a coding change that is associated with continuous morphological variation. This work offers novel insights into the development and evolution of the craniofacial skeleton, underscores the evolutionary potential of neural crest cells, and extends our understanding of the genetic nature of mutations that underlie divergence in complex phenotypes. PMID:25234704

Morphological Awareness and Its Role in Compensation in Adults with Dyslexia.

PubMed

Law, Jeremy M; Wouters, Jan; Ghesquière, Pol

2015-08-01

This study examines the role of morphological awareness (MA) in literacy achievement and compensation in word reading of adults with dyslexia through an exploration of three questions: (1) Do adult dyslexics demonstrate a deficit in MA, and how is this potential deficit related to phonological awareness (PA)? (2) Does MA contribute independently to literacy skills equally in dyslexics and control readers? and (3) Do MA and PA skills differ in compensated and noncompensated dyslexics? A group of dyslexic and normal reading university students matched for age, education and IQ participated in this study. Group analysis demonstrated an MA deficit in dyslexics; as well, MA was found to significantly predict a greater proportion of word reading and spelling within the dyslexic group compared with the controls. Compensated dyslexics were also found to perform significantly better on the morphological task than noncompensated dyslexics. Additionally, no statistical difference was observed in MA between the normal reading controls and the compensated group (independent of PA and vocabulary). Results suggest that intact and strong MA skills contribute to the achieved compensation of this group of adults with dyslexia. Implications for MA based intervention strategies for people with dyslexia are discussed. Copyright © 2015 John Wiley & Sons, Ltd.

P(VDF/TrFE) morphologies and crystalline lamellae orientations dependence on substrates characterized by scanning probe microscopy

NASA Astrophysics Data System (ADS)

Lakbita, Imane; El-Hami, Khalil

2018-02-01

Ultra-thin films of the polyvinylidene fluoride and trifluoroethylene (P(VDF/TrFE)) copolymer were elaborated on various different substrates by the spin coating method. The purpose of this paper is to study the P(VDF/TrFE) morphologies and crystalline lamellae orientation dependence on substrates. We chose the potassium chloride (KCl), Sodium Chloride (NaCl) and Potassium Bromide (KBr) with the [110] direction and the highly ordered pyrolytic graphite (HOPG) substrates because they present different crystallographic structures. The atomic force microscopy is used for imaging P(VDF/TrFE) morphologies with nanometer resolution and determining the surface roughness. The analysis of the AFM topography images revealed that the P(VDF/TrFE) film has, almost, the same texture on KCl, NaCl or on KBr substrates and their crystalline lamellae had grown in two preferred orientations. Unlike the HOPG substrate, their crystalline lamellae were entangled, randomly oriented and positioned adjacent to each other. The growth texture of the P(VDF/TrFE) copolymer showed experimentally a strong dependence on substrate types. Since the P(VDF/TrFE) is ferroelectric, piezoelectric and pyroelectric, this finding may lead to potential applications.

X-Ray Morphological Analysis of the Planck ESZ Clusters

NASA Astrophysics Data System (ADS)

Lovisari, Lorenzo; Forman, William R.; Jones, Christine; Ettori, Stefano; Andrade-Santos, Felipe; Arnaud, Monique; Démoclès, Jessica; Pratt, Gabriel W.; Randall, Scott; Kraft, Ralph

2017-09-01

X-ray observations show that galaxy clusters have a very large range of morphologies. The most disturbed systems, which are good to study how clusters form and grow and to test physical models, may potentially complicate cosmological studies because the cluster mass determination becomes more challenging. Thus, we need to understand the cluster properties of our samples to reduce possible biases. This is complicated by the fact that different experiments may detect different cluster populations. For example, Sunyaev-Zeldovich (SZ) selected cluster samples have been found to include a greater fraction of disturbed systems than X-ray selected samples. In this paper we determine eight morphological parameters for the Planck Early Sunyaev-Zeldovich (ESZ) objects observed with XMM-Newton. We found that two parameters, concentration and centroid shift, are the best to distinguish between relaxed and disturbed systems. For each parameter we provide the values that allow selecting the most relaxed or most disturbed objects from a sample. We found that there is no mass dependence on the cluster dynamical state. By comparing our results with what was obtained with REXCESS clusters, we also confirm that the ESZ clusters indeed tend to be more disturbed, as found by previous studies.

X-Ray Morphological Analysis of the Planck ESZ Clusters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lovisari, Lorenzo; Forman, William R.; Jones, Christine

2017-09-01

X-ray observations show that galaxy clusters have a very large range of morphologies. The most disturbed systems, which are good to study how clusters form and grow and to test physical models, may potentially complicate cosmological studies because the cluster mass determination becomes more challenging. Thus, we need to understand the cluster properties of our samples to reduce possible biases. This is complicated by the fact that different experiments may detect different cluster populations. For example, Sunyaev–Zeldovich (SZ) selected cluster samples have been found to include a greater fraction of disturbed systems than X-ray selected samples. In this paper wemore » determine eight morphological parameters for the Planck Early Sunyaev–Zeldovich (ESZ) objects observed with XMM-Newton . We found that two parameters, concentration and centroid shift, are the best to distinguish between relaxed and disturbed systems. For each parameter we provide the values that allow selecting the most relaxed or most disturbed objects from a sample. We found that there is no mass dependence on the cluster dynamical state. By comparing our results with what was obtained with REXCESS clusters, we also confirm that the ESZ clusters indeed tend to be more disturbed, as found by previous studies.« less

Quantification of mammalian tumor cell state plasticity with digital holographic cytometry

NASA Astrophysics Data System (ADS)

Hejna, Miroslav; Jorapur, Aparna; Zhang, Yuntian; Song, Jun S.; Judson, Robert L.

2018-02-01

Individual cells within isogenic tumor populations can exhibit distinct cellular morphologies, behaviors, and molecular profiles. Cell state plasticity refers to the propensity of a cell to transition between these different morphologies and behaviors. Elevation of cell state plasticity is thought to contribute to critical stages in tumor evolution, including metastatic dissemination and acquisition of therapeutic resistance. However, methods for quantifying general plasticity in mammalian cells remain limited. Working with a HoloMonitor M4 digital holographic cytometry platform, we have established a machine learning-based pipeline for high accuracy and label-free classification of adherent cells. We use twenty-six morphological and optical density-derived features for label-free identification of cell state in heterogeneous cultures. The system is housed completely within a mammalian cell incubator, permitting the monitoring of changes in cell state over time. Here we present an application of our approach for studying cell state plasticity. Human melanoma cell lines of known metastatic potential were monitored in standard growth conditions. The rate of feature change was quantified for each individual cell in the populations. We observed that cells of higher metastatic potential exhibited more rapid fluctuation of cell state in homeostatic conditions. The approach we demonstrate will be advantageous for further investigations into the factors that influence cell state plasticity.

A diagnostic algorithm for atypical spitzoid tumors: guidelines for immunohistochemical and molecular assessment.

PubMed

Cho-Vega, Jeong Hee

2016-07-01

Atypical spitzoid tumors are a morphologically diverse group of rare melanocytic lesions most frequently seen in children and young adults. As atypical spitzoid tumors bear striking resemblance to Spitz nevus and spitzoid melanomas clinically and histopathologically, it is crucial to determine its malignant potential and predict its clinical behavior. To date, many researchers have attempted to differentiate atypical spitzoid tumors from unequivocal melanomas based on morphological, immonohistochemical, and molecular diagnostic differences. A diagnostic algorithm is proposed here to assess the malignant potential of atypical spitzoid tumors by using a combination of immunohistochemical and cytogenetic/molecular tests. Together with classical morphological evaluation, this algorithm includes a set of immunohistochemistry assays (p16(Ink4a), a dual-color Ki67/MART-1, and HMB45), fluorescence in situ hybridization (FISH) with five probes (6p25, 8q24, 11q13, CEN9, and 9p21), and an array-based comparative genomic hybridization. This review discusses details of the algorithm, the rationale of each test used in the algorithm, and utility of this algorithm in routine dermatopathology practice. This algorithmic approach will provide a comprehensive diagnostic tool that complements conventional histological criteria and will significantly contribute to improve the diagnosis and prediction of the clinical behavior of atypical spitzoid tumors.

Does structural complexity determine the morphology of assemblages? An experimental test on three continents.

PubMed

Gibb, Heloise; Parr, Catherine L

2013-01-01

Understanding how species will respond to global change depends on our ability to distinguish generalities from idiosyncrasies. For diverse, but poorly known taxa, such as insects, species traits may provide a short-cut to predicting species turnover. We tested whether ant traits respond consistently to habitat complexity across geographically independent ant assemblages, using an experimental approach and baits. We repeated our study in six paired simple and complex habitats on three continents with distinct ant faunas. We also compared traits amongst ants with different foraging strategies. We hypothesised that ants would be larger, broader, have longer legs and more dorsally positioned eyes in simpler habitats. In agreement with predictions, ants had longer femurs and dorsally positioned eyes in simple habitats. This pattern was most pronounced for ants that discovered resources. Body size and pronotum width responded as predicted for experimental treatments, but were inconsistent across continents. Monopolising ants were smaller, with shorter femurs than those that occupied or discovered resources. Consistent responses for several traits suggest that many, but not all, aspects of morphology respond predictably to habitat complexity, and that foraging strategy is linked with morphology. Some traits thus have the potential to be used to predict the direction of species turnover, changes in foraging strategy and, potentially, evolution in response to changes in habitat structure.

Mitochondrial respiration is sensitive to cytoarchitectural breakdown.

PubMed

Kandel, Judith; Angelin, Alessia A; Wallace, Douglas C; Eckmann, David M

2016-11-07

An abundance of research suggests that cellular mitochondrial and cytoskeletal disruption are related, but few studies have directly investigated causative connections between the two. We previously demonstrated that inhibiting microtubule and microfilament polymerization affects mitochondrial motility on the whole-cell level in fibroblasts. Since mitochondrial motility can be indicative of mitochondrial function, we now further characterize the effects of these cytoskeletal inhibitors on mitochondrial potential, morphology and respiration. We found that although they did not reduce mitochondrial inner membrane potential, cytoskeletal toxins induced significant decreases in basal mitochondrial respiration. In some cases, basal respiration was only affected after cells were pretreated with the calcium ionophore A23187 in order to stress mitochondrial function. In most cases, mitochondrial morphology remained unaffected, but extreme microfilament depolymerization or combined intermediate doses of microtubule and microfilament toxins resulted in decreased mitochondrial lengths. Interestingly, these two particular exposures did not affect mitochondrial respiration in cells not sensitized with A23187, indicating an interplay between mitochondrial morphology and respiration. In all cases, inducing maximal respiration diminished differences between control and experimental groups, suggesting that reduced basal respiration originates as a largely elective rather than pathological symptom of cytoskeletal impairment. However, viability experiments suggest that even this type of respiration decrease may be associated with cell death.

Did Adult Diurnal Activity Influence the Evolution of Wing Morphology in Opoptera Butterflies?

PubMed

Penz, C M; Heine, K B

2016-02-01

The butterfly genus Opoptera includes eight species, three of which have diurnal habits while the others are crepuscular (the usual activity period for members of the tribe Brassolini). Although never measured in the field, it is presumed that diurnal Opoptera species potentially spend more time flying than their crepuscular relatives. If a shift to diurnal habits potentially leads to a higher level of activity and energy expenditure during flight, then selection should operate on increased aerodynamic and energetic efficiency, leading to changes in wing shape. Accordingly, we ask whether diurnal habits have influenced the evolution of wing morphology in Opoptera. Using phylogenetically independent contrasts and Wilcoxon rank sum tests, we confirmed our expectation that the wings of diurnal species have higher aspect ratios (ARs) and lower wing centroids (WCs) than crepuscular congeners. These wing shape characteristics are known to promote energy efficiency during flight. Three Opoptera wing morphotypes established a priori significantly differed in AR and WC values. The crepuscular, cloud forest dweller Opoptera staudingeri (Godman & Salvin) was exceptional in having an extended forewing tip and the highest AR and lowest WC within Opoptera, possibly to facilitate flight in a cooler environment. Our study is the first to investigate how butterfly wing morphology might evolve as a response to a behavioral shift in adult time of activity.

Which Factors Determine Spatial Segregation in the South American Opossums (Didelphis aurita and D. albiventris)? An Ecological Niche Modelling and Geometric Morphometrics Approach

PubMed Central

Cáceres, Nilton Carlos; de Moraes Weber, Marcelo; Melo, Geruza Leal; Meloro, Carlo; Sponchiado, Jonas; Carvalho, Renan dos Santos; Bubadué, Jamile de Moura

2016-01-01

Didelphis albiventris and D. aurita are Neotropical marsupials that share a unique evolutionary history and both are largely distributed throughout South America, being primarily allopatric throughout their ranges. In the Araucaria moist forest of Southern Brazil these species are sympatric and they might potentially compete having similar ecology. For this reason, they are ideal biological models to address questions about ecological character displacement and how closely related species might share their geographic space. Little is known about how two morphologically similar species of marsupials may affect each other through competition, if by competitive exclusion and competitive release. We combined ecological niche modeling and geometric morphometrics to explore the possible effects of competition on their distributional ranges and skull morphology. Ecological niche modeling was used to predict their potential distribution and this method enabled us to identify a case of biotic exclusion where the habit generalist D. albiventris is excluded by the presence of the specialist D. aurita. The morphometric analyses show that a degree of shape discrimination occurs between the species, strengthened by allometric differences, which possibly allowed them to occupy marginally different feeding niches supplemented by behavioral shift in contact areas. Overlap in skull morphology is shown between sympatric and allopatric specimens and a significant, but weak, shift in shape occurs only in D. aurita in sympatric areas. This could be a residual evidence of a higher past competition between both species, when contact zones were possibly larger than today. Therefore, the specialist D. aurita acts a biotic barrier to D. albiventris when niche diversity is not available for coexistence. On the other hand, when there is niche diversification (e.g. habitat mosaic), both species are capable to coexist with a minimal competitive effect on the morphology of D. aurita. PMID:27336371

Permafrost collapse alters soil carbon stocks, respiration, CH4 , and N2O in upland tundra.

PubMed

Abbott, Benjamin W; Jones, Jeremy B

2015-12-01

Release of greenhouse gases from thawing permafrost is potentially the largest terrestrial feedback to climate change and one of the most likely to occur; however, estimates of its strength vary by a factor of thirty. Some of this uncertainty stems from abrupt thaw processes known as thermokarst (permafrost collapse due to ground ice melt), which alter controls on carbon and nitrogen cycling and expose organic matter from meters below the surface. Thermokarst may affect 20-50% of tundra uplands by the end of the century; however, little is known about the effect of different thermokarst morphologies on carbon and nitrogen release. We measured soil organic matter displacement, ecosystem respiration, and soil gas concentrations at 26 upland thermokarst features on the North Slope of Alaska. Features included the three most common upland thermokarst morphologies: active-layer detachment slides, thermo-erosion gullies, and retrogressive thaw slumps. We found that thermokarst morphology interacted with landscape parameters to determine both the initial displacement of organic matter and subsequent carbon and nitrogen cycling. The large proportion of ecosystem carbon exported off-site by slumps and slides resulted in decreased ecosystem respiration postfailure, while gullies removed a smaller portion of ecosystem carbon but strongly increased respiration and N2 O concentration. Elevated N2 O in gully soils persisted through most of the growing season, indicating sustained nitrification and denitrification in disturbed soils, representing a potential noncarbon permafrost climate feedback. While upland thermokarst formation did not substantially alter redox conditions within features, it redistributed organic matter into both oxic and anoxic environments. Across morphologies, residual organic matter cover, and predisturbance respiration explained 83% of the variation in respiration response. Consistent differences between upland thermokarst types may contribute to the incorporation of this nonlinear process into projections of carbon and nitrogen release from degrading permafrost. © 2015 John Wiley & Sons Ltd.

The Effect of New Zealand Kanuka, Manuka and Clover Honeys on Bacterial Growth Dynamics and Cellular Morphology Varies According to the Species

PubMed Central

Lu, Jing; Carter, Dee A.; Turnbull, Lynne; Rosendale, Douglas; Hedderley, Duncan; Stephens, Jonathan; Gannabathula, Swapna; Steinhorn, Gregor; Schlothauer, Ralf C.; Whitchurch, Cynthia B.; Harry, Elizabeth J.

2013-01-01

Treatment of chronic wounds is becoming increasingly difficult due to antibiotic resistance. Complex natural products with antimicrobial activity, such as honey, are now under the spotlight as alternative treatments to antibiotics. Several studies have shown honey to have broad-spectrum antibacterial activity at concentrations present in honey dressings, and resistance to honey has not been attainable in the laboratory. However not all honeys are the same and few studies have used honey that is well defined both in geographic and chemical terms. Here we have used a range of concentrations of clover honey and a suite of manuka and kanuka honeys from known geographical locations, and for which the floral source and concentration of methylglyoxal and hydrogen peroxide potential were defined, to determine their effect on growth and cellular morphology of four bacteria: Bacillus subtilis, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. While the general trend in effectiveness of growth inhibition was manuka>manuka-kanuka blend>kanuka>clover, the honeys had varying and diverse effects on the growth and cellular morphology of each bacterium, and each organism had a unique response profile to these honeys. P. aeruginosa showed a markedly different pattern of growth inhibition to the other three organisms when treated with sub-inhibitory concentrations of honey, being equally sensitive to all honeys, including clover, and the least sensitive to honey overall. While hydrogen peroxide potential contributed to the antibacterial activity of the manuka and kanuka honeys, it was never essential for complete growth inhibition. Cell morphology analysis also showed a varied and diverse set of responses to the honeys that included cell length changes, cell lysis, and alterations to DNA appearance. These changes are likely to reflect the different regulatory circuits of the organisms that are activated by the stress of honey treatment. PMID:23418472

Isolation and characterization of mesoangioblasts from facioscapulohumeral muscular dystrophy muscle biopsies.

PubMed

Morosetti, Roberta; Mirabella, Massimiliano; Gliubizzi, Carla; Broccolini, Aldobrando; Sancricca, Cristina; Pescatori, Mario; Gidaro, Teresa; Tasca, Giorgio; Frusciante, Roberto; Tonali, Pietro Attilio; Cossu, Giulio; Ricci, Enzo

2007-12-01

Facioscapulohumeral muscular dystrophy (FSHD) is the third most frequent inherited muscle disease. Because in FSHD patients the coexistence of affected and unaffected muscles is common, myoblasts expanded from unaffected FSHD muscles have been proposed as suitable tools for autologous cell transplantation. Mesoangioblasts are a new class of adult stem cells of mesodermal origin, potentially useful for the treatment of primitive myopathies of different etiology. Here, we report the isolation and characterization of mesoangioblasts from FSHD muscle biopsies and describe morphology, proliferation, and differentiation abilities of both mesoangioblasts and myoblasts derived from various affected and unaffected muscles of nine representative FSHD patients. We demonstrate that mesoangioblasts can be efficiently isolated from FSHD muscle biopsies and expanded to an amount of cells necessary to transplant into an adult patient. Proliferating mesoangioblasts from all muscles examined did not differ from controls in terms of morphology, phenotype, proliferation rate, or clonogenicity. However, their differentiation ability into skeletal muscle was variably impaired, and this defect correlated with the overall disease severity and the degree of histopathologic abnormalities of the muscle of origin. A remarkable differentiation defect was observed in mesoangioblasts from all mildly to severely affected FSHD muscles, whereas mesoangioblasts from morphologically normal muscles showed no myogenic differentiation block. Our study could open the way to cell therapy for FSHD patients to limit muscle damage in vivo through the use of autologous mesoangioblasts capable of reaching damaged muscles and engrafting into them, without requiring immune suppression or genetic correction in vitro. Disclosure of potential conflicts of interest is found at the end of this article.

Inhibition of quantum size effects from surface dangling bonds: The first principles study on different morphology SiC nanowires

NASA Astrophysics Data System (ADS)

Li, Yan-Jing; Li, Shu-Long; Gong, Pei; Li, Ya-Lin; Fang, Xiao-Yong; Jia, Ya-Hui; Cao, Mao-Sheng

2018-06-01

In recent years, we investigated the structure and photoelectric properties of Silicon carbide nanowires (SiCNWs) with different morphologies and sizes by using the first-principle in density functional theory, and found a phenomenon that is opposite to quantum size effect, namely, the band gap of nanowires increases with the increase of the diameter. To reveal the nature of this phenomenon, we further carry out the passivation of SiCNWs. The results show that the hydrogenated SiCNWs are direct band gap semiconductors, and the band gap decreases with the diameter increasing, which indicates the dangling bonds of the SiCNWs suppress its quantum size effect. The optical properties of SiCNWs with different diameters before and after hydrogenated are compared, we found that these surface dangling bonds lead to spectral shift which is different with quantum size effect of SiCNWs. These results have potential scientific value to deepen the understanding of the photoelectric properties of SiCNWs and to promote the development of optoelectronic devices.

Moving Forward: Age Effects on the Cerebellum Underlie Cognitive and Motor Declines

PubMed Central

Bernard, Jessica A.; Seidler, Rachael D.

2014-01-01

Though the cortical contributions to age-related declines in motor and cognitive performance are well-known, the potential contributions of the cerebellum are less clear. The diverse functions of the cerebellum make it an important structure to investigate in aging. Here, we review the extant literature on this topic. To date, there is evidence to indicate that there are morphological age differences in the cerebellum that are linked to motor and cognitive behavior. Cerebellar morphology is often as good as -- or even better -- at predicting performance than the prefrontal cortex. We also touch on the few studies using functional neuroimaging and connectivity analyses that further implicate the cerebellum in age-related performance declines. Importantly, we provide a conceptual framework for the cerebellum influencing age differences in performance, centered on the notion of degraded internal models. The evidence indicating that cerebellar age differences associate with performance highlights the need for additional work in this domain to further elucidate the role of the cerebellum in age differences in movement control and cognitive function. PMID:24594194

Aggregation in charged nanoparticles solutions induced by different interactions

NASA Astrophysics Data System (ADS)

Abbas, S.; Kumar, Sugam; Aswal, V. K.; Kohlbrecher, J.

2016-05-01

Small-angle neutron scattering (SANS) has been used to study the aggregation of anionic silica nanoparticles as induced through different interactions. The nanoparticle aggregation is induced by addition of salt (NaCl), cationic protein (lysozyme) and non-ionic surfactant (C12E10) employing different kind of interactions. The results show that the interaction in presence of salt can be explained using DLVO theory whereas non-DLVO forces play important role for interaction of nanoparticles with protein and surfactant. The presence of salt screens the repulsion between charged nanoparticles giving rise to a net attraction in the DLVO potential. On the other hand, strong electrostatic attraction between nanoparticle and oppositely charged protein leads to protein-mediated nanoparticle aggregation. In case of non-ionic surfactant, the relatively long-range attractive depletion interaction is found to be responsible for the particle aggregation. Interestingly, the completely different interactions lead to similar kind of aggregate morphology. The nanoparticle aggregates formed are found to have mass fractal nature having a fractal dimension (~2.5) consistent with diffusion limited type of fractal morphology in all three cases.

Aggregation in charged nanoparticles solutions induced by different interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abbas, S.; Kumar, Sugam; Aswal, V. K., E-mail: vkaswal@barc.gov.in

2016-05-23

Small-angle neutron scattering (SANS) has been used to study the aggregation of anionic silica nanoparticles as induced through different interactions. The nanoparticle aggregation is induced by addition of salt (NaCl), cationic protein (lysozyme) and non-ionic surfactant (C12E10) employing different kind of interactions. The results show that the interaction in presence of salt can be explained using DLVO theory whereas non-DLVO forces play important role for interaction of nanoparticles with protein and surfactant. The presence of salt screens the repulsion between charged nanoparticles giving rise to a net attraction in the DLVO potential. On the other hand, strong electrostatic attraction betweenmore » nanoparticle and oppositely charged protein leads to protein-mediated nanoparticle aggregation. In case of non-ionic surfactant, the relatively long-range attractive depletion interaction is found to be responsible for the particle aggregation. Interestingly, the completely different interactions lead to similar kind of aggregate morphology. The nanoparticle aggregates formed are found to have mass fractal nature having a fractal dimension (~2.5) consistent with diffusion limited type of fractal morphology in all three cases.« less

Non-Mulberry and Mulberry Silk Protein Sericins as Potential Media Supplement for Animal Cell Culture.

PubMed

Sahu, Neety; Pal, Shilpa; Sapru, Sunaina; Kundu, Joydip; Talukdar, Sarmistha; Singh, N Ibotambi; Yao, Juming; Kundu, Subhas C

2016-01-01

Silk protein sericins, in the recent years, find application in cosmetics and pharmaceuticals and as biomaterials. We investigate the potential of sericin, extracted from both mulberry Bombyx mori and different non-mulberry sources, namely, tropical tasar, Antheraea mylitta; muga, Antheraea assama; and eri, Samia ricini, as growth supplement in serum-free culture medium. Sericin supplemented media containing different concentrations of sericins from the different species are examined for attachment, growth, proliferation, and morphology of fibrosarcoma cells. The optimum sericin supplementation seems to vary with the source of sericins. The results indicate that all the sericins promote the growth of L929 cells in serum-free culture media; however, S. ricini sericin seems to promote better growth of cells amongst other non-mulberry sericins.

Non-Mulberry and Mulberry Silk Protein Sericins as Potential Media Supplement for Animal Cell Culture

PubMed Central

Sahu, Neety; Pal, Shilpa; Sapru, Sunaina; Kundu, Joydip; Talukdar, Sarmistha; Singh, N. Ibotambi; Yao, Juming

2016-01-01

Silk protein sericins, in the recent years, find application in cosmetics and pharmaceuticals and as biomaterials. We investigate the potential of sericin, extracted from both mulberry Bombyx mori and different non-mulberry sources, namely, tropical tasar, Antheraea mylitta; muga, Antheraea assama; and eri, Samia ricini, as growth supplement in serum-free culture medium. Sericin supplemented media containing different concentrations of sericins from the different species are examined for attachment, growth, proliferation, and morphology of fibrosarcoma cells. The optimum sericin supplementation seems to vary with the source of sericins. The results indicate that all the sericins promote the growth of L929 cells in serum-free culture media; however, S. ricini sericin seems to promote better growth of cells amongst other non-mulberry sericins. PMID:27517047

The role of shelf morphology and antecedent setting in the preservation of palaeo-shoreline (beachrock and aeolianite) sequences: the SE African shelf

NASA Astrophysics Data System (ADS)

Green, Andrew N.; Cooper, J. Andrew G.; Salzmann, Leslee

2018-02-01

On the SE African shelf, a submerged shoreline at a depth of 60 m is examined and its attributes compared between two shelf sectors with different morphologies, yet similar energy regimes. The aim is to assess the controls of antecedent conditioning on shoreline development and later preservation from transgressive ravinement. Using a combination of multibeam bathymetry and single-channel seismic profiles, the stratigraphy and morphology of the shoreline is investigated. Low-gradient bedrock examples reveal several distinctive seismic facies, including onlapping chaotic reflector packages which are interpreted as calcarenite rubble fields. These palaeo-shorelines possess planform equilibrium morphologies, including parabolic dunes and blowout forms along with relict shore platforms. They are strongly associated with incised valleys of last glacial maximum age which underlie the shoreline locations; these provide wide, back -barrier accommodation space during transgression. In contrast, palaeo-shorelines on the steeper-gradient shelf have a simpler stratigraphic arrangement. They are not as well preserved, are generally covered by thick drapes of sediment, and lack the elaborate planform morphologies of their lower-shelf gradient equivalents. Isolated incised valleys and the steep bedrock gradient limit accommodation space. The comparison indicates that antecedent bedrock slope and available accommodation are amongst the dominant controls on overstepping, and thus potential preservation, of palaeo-shorelines on the shelf. Lower-gradient shelves not only promote rapid shoreline translation but, together with wide, sandy back -barrier accommodation, also foster larger barrier volumes. In suitable climates such as in the Mediterranean and other sub-tropical areas, the ensuing shoreline stability promotes rapid and effective cementation of the barrier. In comparison, steep bedrock profiles with limited back -barrier accommodation have much lower preservation potential. Transgressive ravinement is more focussed on steep slopes, effectively removing more material during the ravinement process. The more dynamic environment may also reduce the effectiveness of diagenesis. The potential of beachrock and aeolianite palaeo-shorelines as submerged sea-level indicators may be optimal in low-gradient settings in Mediterranean to subtropical environments.

The relationship between morphological and behavioral mimicry in hover flies (Diptera: Syrphidae).

PubMed

Penney, Heather D; Hassall, Christopher; Skevington, Jeffrey H; Lamborn, Brent; Sherratt, Thomas N

2014-02-01

Palatable (Batesian) mimics of unprofitable models could use behavioral mimicry to compensate for the ease with which they can be visually discriminated or to augment an already close morphological resemblance. We evaluated these contrasting predictions by assaying the behavior of 57 field-caught species of mimetic hover flies (Diptera: Syrphidae) and quantifying their morphological similarity to a range of potential hymenopteran models. A purpose-built phylogeny for the hover flies was used to control for potential lack of independence due to shared evolutionary history. Those hover fly species that engage in behavioral mimicry (mock stinging, leg waving, wing wagging) were all large wasp mimics within the genera Spilomyia and Temnostoma. While the behavioral mimics assayed were good morphological mimics, not all good mimics were behavioral mimics. Therefore, while the behaviors may have evolved to augment good morphological mimicry, they do not advantage all good mimics.

The surface stability and morphology of tobermorite 11 Å from first principles

NASA Astrophysics Data System (ADS)

Mutisya, Sylvia M.; Miranda, Caetano R.

2018-06-01

Tobermorite minerals are important in many industrial processes typically occurring in hydrous environment. Their functionality is therefore governed in various aspects by their morphology and surface stability/reactivity. Here, we present the results of the surface energies and morphology of normal tobermorite 11 Å in a water vapor environment investigated by employing first principles atomistic thermodynamic calculations. For the low index tobermorite surfaces studied, the calculated surface energies fall within a narrow range (0.41-0.97 J/m2) with the (0 0 4) surface being the most stable. The equilibrium morphology is a thin pseudohexagonal plate elongated along the b axis. The hydrated surfaces are more stable at high water vapor chemical potentials with the stability enhanced as the water partial pressures are varied from ambient to supercritical hydrothermal conditions. Increasing the water vapor chemical potential gives rise to a smaller size of the tobermorite crystal, with the equilibrium morphology remaining unaltered.

Osteoconductive composite graft based on bacterial synthesized hydroxyapatite nanoparticles doped with different ions: From synthesis to in vivo studies.

PubMed

Ahmadzadeh, Elham; Talebnia, Farid; Tabatabaei, Meisam; Ahmadzadeh, Hossein; Mostaghaci, Babak

2016-07-01

To repair damaged bone tissues, osteoconductive bone graft substitutes are required for enhancement of the regenerative potential of osteoblast cells. Nanostructured hydroxyapatite is a bioactive ceramic used for bone tissue engineering purposes. In this study, carbonate hydroxyapatite (cHA) and zinc-magnesium substituted hydroxyapatite (Zn-Mg-HA) nanoparticles were synthesized via biomineralization method using Enterobacter aerogenes. The structural phase composition and the morphology of the samples were analyzed using appropriate powder characterization methods. Next, a composite graft was fabricated by using polyvinyl alcohol and both cHA and Zn-Mg-HA samples. In vivo osteogenic potential of the graft was then investigated in a rabbit tibial osteotomy model. Histological, radiological and morphological studies showed that the graft was mineralized by the newly formed bone tissue without signs of inflammation or infection after 4 weeks of implantation. These histomorphometric results suggest that the fabricated graft can function as a potent osteoconductive bone tissue substitute. Copyright © 2016 Elsevier Inc. All rights reserved.

Morphological characterization of coral reefs by combining lidar and MBES data: A case study from Yuanzhi Island, South China Sea

NASA Astrophysics Data System (ADS)

Zhang, Kai; Yang, Fanlin; Zhang, Hande; Su, Dianpeng; Li, QianQian

2017-06-01

The correlation between seafloor morphological features and biological complexity has been identified in numerous recent studies. This research focused on the potential for accurate characterization of coral reefs based on high-resolution bathymetry from multiple sources. A standard deviation (STD) based method for quantitatively characterizing terrain complexity was developed that includes robust estimation to correct for irregular bathymetry and a calibration for the depth-dependent variablity of measurement noise. Airborne lidar and shipborne sonar bathymetry measurements from Yuanzhi Island, South China Sea, were merged to generate seamless high-resolution coverage of coral bathymetry from the shoreline to deep water. The new algorithm was applied to the Yuanzhi Island surveys to generate maps of quantitive terrain complexity, which were then compared to in situ video observations of coral abundance. The terrain complexity parameter is significantly correlated with seafloor coral abundance, demonstrating the potential for accurately and efficiently mapping coral abundance through seafloor surveys, including combinations of surveys using different sensors.

Mechanisms of gender-related outcome differences after carotid endarterectomy.

PubMed

den Hartog, Anne G; Algra, Ale; Moll, Frans L; de Borst, Gert J

2010-10-01

Large randomized trials have confirmed a difference in outcome after carotid endarterectomy (CEA) between men and women. In this review, we aimed to provide an overview of the gender-specific characteristics causing these perioperative and long-term outcome differences between men and women after CEA. A systematic search strategy with the synonyms of 'gender' and 'carotid endarterectomy' was conducted from PubMed and EMBASE databases. Only 11 relevant studies specifically discussing gender-specific related characteristics and their influence on outcome after CEA could be identified. Due to the limited number of included studies, pooling of findings was impossible, and results are presented in a descriptive manner. Each included study described only one possible gender-specific factor. Differences in carotid artery diameter, sex hormones, sensitivity for antiplatelet therapy, plaque morphology, occurrence of microembolic signals, and restenosis rate have all been suggested as gender-specific characteristics influencing outcome after CEA. Higher embolic potential in women and relatively stable female plaque morphology are the best-described factors influencing the difference in outcomes between men and women. However, the overall evidence for outcome differences by gender-specific characteristics in the literature is limited. Copyright © 2010 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Two-component gelator isomers with different combination of amine and acid: Helical/non-helical morphology and selective adsorption of dyes.

PubMed

Han, Xiaoyu; Liu, Jiahui; Zhao, Chaoyue; Zhang, Bao; Xu, Xiufang; Song, Jian

2018-09-01

Hydrogels induced by two-component gelator isomers based on the different amine/acid interactions were investigated. Scanning electron microscopy and atomic force microscopy images of the xerogel obtained from the two hydrogels revealed different assembly morphologies. While left-handed helical fibers were observed for the amine-acid based xerogel, acid-amine underwent self-assembly to afford smooth fibers. Fourier transform infrared spectroscopy, fluorescence, and X-ray diffraction measurements combined with density functional theory calculations suggested that the different self-assembly patterns of gelators resulted in opposite electric charges on the xerogel surfaces, in line with Zeta potential measurements. Based on these opposite charges resulting from their different self-assemblies, both xerogels demonstrated efficient dye adsorption abilities with different selectivities. Interestingly, the adsorption performance was not influenced by the salt in the dye solution. Furthermore, the xerogels still showed high dye adsorption efficiency after four cycles. These results provide a two-component hydrogel method for the purification of dye-polluted water systems, while also paving the way for future design of functionalized supramolecular self-assembly systems. Copyright © 2018 Elsevier Inc. All rights reserved.

Cathodic Potential Dependence of Electrochemical Reduction of SiO2 Granules in Molten CaCl2

NASA Astrophysics Data System (ADS)

Yang, Xiao; Yasuda, Kouji; Nohira, Toshiyuki; Hagiwara, Rika; Homma, Takayuki

2016-09-01

As part of an ongoing fundamental study to develop a new process for producing solar-grade silicon, this paper examines the effects of cathodic potential on reduction kinetics, current efficiency, morphology, and purity of Si product during electrolysis of SiO2 granules in molten CaCl2 at 1123 K (850 °C). SiO2 granules were electrolyzed potentiostatically at different cathodic potentials (0.6, 0.8, 1.0, and 1.2 V vs Ca2+/Ca). The reduction kinetics was evaluated based on the growth of the reduced Si layer and the current behavior during electrolysis. The results suggest that a more negative cathodic potential is favorable for faster reduction. Current efficiencies in 60 minutes are greater than 65 pct at all the potentials examined. Si wires with sub-micron diameters are formed, and their morphologies show little dependence on the cathodic potential. The impurities in the Si product can be controlled at low level. The rate-determining step for the electrochemical reduction of SiO2 granules in molten CaCl2 changes with time. At the initial stage of electrolysis, the electron transfer is the rate-determining step. At the later stage, the diffusion of O2- ions is the rate-determining step. The major cause of the decrease in reduction rate with increasing electrolysis time is the potential drop from the current collector to the reaction front due to the increased contact resistance among the reduced Si particles.

Intraspecific plant-soil feedback and intraspecific overyielding in Arabidopsis thaliana.

PubMed

Bukowski, Alexandra R; Petermann, Jana S

2014-06-01

Understanding the mechanisms of community coexistence and ecosystem functioning may help to counteract the current biodiversity loss and its potentially harmful consequences. In recent years, plant-soil feedback that can, for example, be caused by below-ground microorganisms has been suggested to play a role in maintaining plant coexistence and to be a potential driver of the positive relationship between plant diversity and ecosystem functioning. Most of the studies addressing these topics have focused on the species level. However, in addition to interspecific interactions, intraspecific interactions might be important for the structure of natural communities. Here, we examine intraspecific coexistence and intraspecific diversity effects using 10 natural accessions of the model species Arabidopsis thaliana (L.) Heynh. We assessed morphological intraspecific diversity by measuring several above- and below-ground traits. We performed a plant-soil feedback experiment that was based on these trait differences between the accessions in order to determine whether A. thaliana experiences feedback at intraspecific level as a result of trait differences. We also experimentally tested the diversity-productivity relationship at intraspecific level. We found strong differences in above- and below-ground traits between the A. thaliana accessions. Overall, plant-soil feedback occurred at intraspecific level. However, accessions differed in the direction and strength of this feedback: Some accessions grew better on their own soils, some on soils from other accessions. Furthermore, we found positive diversity effects within A. thaliana: Accession mixtures produced a higher total above-ground biomass than accession monocultures. Differences between accessions in their feedback response could not be explained by morphological traits. Therefore, we suggest that they might have been caused by accession-specific accumulated soil communities, by root exudates, or by accession-specific resource use based on genetic differences that are not expressed in morphological traits. Synthesis. Our results provide some of the first evidence for intraspecific plant-soil feedback and intraspecific overyielding. These findings may have wider implications for the maintenance of variation within species and the importance of this variation for ecosystem functioning. Our results highlight the need for an increased focus on intraspecific processes in plant diversity research to fully understand the mechanisms of coexistence and ecosystem functioning.

Intraspecific plant–soil feedback and intraspecific overyielding in Arabidopsis thaliana

PubMed Central

Bukowski, Alexandra R; Petermann, Jana S

2014-01-01

Understanding the mechanisms of community coexistence and ecosystem functioning may help to counteract the current biodiversity loss and its potentially harmful consequences. In recent years, plant–soil feedback that can, for example, be caused by below-ground microorganisms has been suggested to play a role in maintaining plant coexistence and to be a potential driver of the positive relationship between plant diversity and ecosystem functioning. Most of the studies addressing these topics have focused on the species level. However, in addition to interspecific interactions, intraspecific interactions might be important for the structure of natural communities. Here, we examine intraspecific coexistence and intraspecific diversity effects using 10 natural accessions of the model species Arabidopsis thaliana (L.) Heynh. We assessed morphological intraspecific diversity by measuring several above- and below-ground traits. We performed a plant–soil feedback experiment that was based on these trait differences between the accessions in order to determine whether A. thaliana experiences feedback at intraspecific level as a result of trait differences. We also experimentally tested the diversity–productivity relationship at intraspecific level. We found strong differences in above- and below-ground traits between the A. thaliana accessions. Overall, plant–soil feedback occurred at intraspecific level. However, accessions differed in the direction and strength of this feedback: Some accessions grew better on their own soils, some on soils from other accessions. Furthermore, we found positive diversity effects within A. thaliana: Accession mixtures produced a higher total above-ground biomass than accession monocultures. Differences between accessions in their feedback response could not be explained by morphological traits. Therefore, we suggest that they might have been caused by accession-specific accumulated soil communities, by root exudates, or by accession-specific resource use based on genetic differences that are not expressed in morphological traits. Synthesis. Our results provide some of the first evidence for intraspecific plant–soil feedback and intraspecific overyielding. These findings may have wider implications for the maintenance of variation within species and the importance of this variation for ecosystem functioning. Our results highlight the need for an increased focus on intraspecific processes in plant diversity research to fully understand the mechanisms of coexistence and ecosystem functioning. PMID:25360284

Provenance effect on carbon assimilation, photochemistry and leaf morphology in Mediterranean Cistus species under chilling stress.

PubMed

Puglielli, G; Cuevas Román, F J; Catoni, R; Moreno Rojas, J M; Gratani, L; Varone, L

2017-07-01

The potential resilience of shrub species to environmental change deserves attention in those areas threatened by climate change, such as the Mediterranean Basin. We asked if leaves produced under different climate conditions through the winter season to spring can highlight the leaf traits involved in determining potential resilience of three Cistus spp. to changing environmental conditions and to what extent intraspecific differences affect such a response. We analysed carbon assimilation, maximum quantum efficiency of PSII photochemistry (F v /F m ) and leaf morphological control of the photosynthetic process in leaves formed through the winter season into spring in C. creticus subsp. eriocephalus (CE), C. salvifolius (CS) and C. monspeliensis (CM) grown from seed of different provenances under common garden conditions. Intraspecific differences were found in F v /F m for CE and CS. Carbon assimilation-related parameters were not affected by provenance. Moreover, our analysis highlighted that the functional relationships investigated can follow seasonal changes and revealed patterns originating from species-specific differences in LMA arising during the favourable period. Cistus spp. have great ability to modify the structure and function of their leaves in the mid-term in order to cope with changing environmental conditions. The F v /F m response to chilling reveals that susceptibility to photoinhibition is a trait under selection in Cistus species. Concerning carbon assimilation, differing ability to control stomatal opening was highlighted between species. Moreover, seasonal changes of the functional relationships investigated can have predictable consequences on species leaf turnover strategies. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.

Manganese Oxide Nanoarray-Based Monolithic Catalysts: Tunable Morphology and High Efficiency for CO Oxidation

DOE PAGES

Chen, Sheng-Yu; Song, Wenqiao; Lin, Hui-Jan; ...

2016-03-08

In this work, a generic one-pot hydrothermal synthesis route has been successfully designed and utilized to in situ grow uniform manganese oxide nanorods and nanowires onto the cordierite honeycomb monolithic substrates, forming a series of nanoarray-based monolithic catalysts. During the synthesis process, three types of potassium salt oxidants have been used with different reduction potentials, i.e., K 2Cr 2O 7, KClO 3, and K 2S 2O 8, denoted as HM-DCM, HM-PCR, and HM-PSF, respectively. The different reduction potentials of the manganese source (Mn 2+) and oxidants induced the formation of manganese oxide nanoarrays with different morphology, surface area, and reactivitymore » of carbon monoxide (CO) oxidation. K 2Cr 2O 7 and KClO 3 can induce sharp and long nanowires with slow growth rates due to their low reduction potentials. In comparison, the nanoarrays of HM-PSF presented shorter nanorods but displayed an efficient 90% CO oxidation conversion at 200 °C (T90) without noble-metal loading. Reducibility tests for the three monolithic catalysts by hydrogen temperature-programmed reduction revealed an activation energy order of HM-PSF > HM-DCM > HM-PCR for CO oxidation. The characterizations of oxygen temperature-programmed desorption and X-ray photoelectron spectroscopy indicated the abundant surface-adsorbed oxygen and lattice oxygen contributing to the superior reactivity of HM-PSF. Finally, the straightforward synthetic process showed a scalable, low-cost, and template-free method to fabricate manganese oxide nanoarray monolithic catalysts for exhaust treatment.« less

Diversity and Distribution of Phenol Oxidase Producing Fungi from Soda Lake and Description of Curvularia lonarensis sp. nov.

PubMed

Sharma, Rahul; Prakash, Om; Sonawane, Mahesh S; Nimonkar, Yogesh; Golellu, Priyanka B; Sharma, Rohit

2016-01-01

Soda lake is hyper alkaline and saline habitat located in closed craters with high evaporation rate. In current study fungal diversity from water and sediment samples of a soda lake (Lonar lake) located in Buldhana district of Maharashtra, India was investigated using extensive culturomics approach and mimicking the natural conditions of Lonar lake in culture media. A total of 104 diverse isolates of extremophilic fungi were recovered from this study and phylogenetically characterized by internal transcribed spacer (ITS) region sequencing. In addition, due to important role of phenol oxidase, and peroxidase in degradation of toxic phenol, lignin, etc., all isolated pure cultures were also screened for extracellular phenol oxidase and peroxidase production potential. Diversity analysis indicated that different groups of extremophilic fungi are present in the water and sediment samples of Lonar lake. A total of 38 species of fungi belonging to 18-different genera were recovered. Out of 104 isolates 32 showed ≤97% sequences similarity, which were morphologically different and could be potential novel isolates of extremophilic fungi. However, out of 104 isolates only 14 showed the extracellular phenol oxidase production potentials at alkaline pH. Curvularia sp. strain MEF018 showed highest phenol oxidase production at alkaline condition and had low sequence similarity with previously characterized species (96% with Curvularia pseudorobusta ). Taxonomic characterization (morphological and physiological) and multi locus sequence analysis (MLSA) using combined alignment of ITS-LSU- gpd of strain MEF018 showed that it is a novel species of the genus Curvularia and hence proposed as Curvularia lonarensis sp. nov.

Diversity and Distribution of Phenol Oxidase Producing Fungi from Soda Lake and Description of Curvularia lonarensis sp. nov.

PubMed Central

Sharma, Rahul; Prakash, Om; Sonawane, Mahesh S.; Nimonkar, Yogesh; Golellu, Priyanka B.; Sharma, Rohit

2016-01-01

Soda lake is hyper alkaline and saline habitat located in closed craters with high evaporation rate. In current study fungal diversity from water and sediment samples of a soda lake (Lonar lake) located in Buldhana district of Maharashtra, India was investigated using extensive culturomics approach and mimicking the natural conditions of Lonar lake in culture media. A total of 104 diverse isolates of extremophilic fungi were recovered from this study and phylogenetically characterized by internal transcribed spacer (ITS) region sequencing. In addition, due to important role of phenol oxidase, and peroxidase in degradation of toxic phenol, lignin, etc., all isolated pure cultures were also screened for extracellular phenol oxidase and peroxidase production potential. Diversity analysis indicated that different groups of extremophilic fungi are present in the water and sediment samples of Lonar lake. A total of 38 species of fungi belonging to 18-different genera were recovered. Out of 104 isolates 32 showed ≤97% sequences similarity, which were morphologically different and could be potential novel isolates of extremophilic fungi. However, out of 104 isolates only 14 showed the extracellular phenol oxidase production potentials at alkaline pH. Curvularia sp. strain MEF018 showed highest phenol oxidase production at alkaline condition and had low sequence similarity with previously characterized species (96% with Curvularia pseudorobusta). Taxonomic characterization (morphological and physiological) and multi locus sequence analysis (MLSA) using combined alignment of ITS-LSU-gpd of strain MEF018 showed that it is a novel species of the genus Curvularia and hence proposed as Curvularia lonarensis sp. nov. PMID:27920761

What tools do we have to study the morphological effects of hydroelectric plants in developing countries? The Chilean case

NASA Astrophysics Data System (ADS)

Alcayaga, Hernan; Caamaño, Diego; Palma, Sebastian; Contreras, Karla

2017-04-01

Countries growing rates are directly related to energy production. Therefore, developed and developing nations are focused on hydropower and dam construction; on the contrary dam removal practices are significantly different among nations, demonstrating the former group a lesser interest on removing structures. Chiles hydropower generation corresponds to 50% of the current grid, having a potential capacity to double the current situation. Thus: ¿What tools can we apply to assess the potential impacts on our rivers? The goal of this project is to study two different reaches located in two separates streams in Central Chile. The Aconcagua River represents a mountain stream (i.e. steep, narrow, and confined) subject to the operation of a hydroelectric system composed by five diversion hydropower plants built during the 90`s. The Rapel River reach corresponds to the last 10km upstream to the outlet; it is a mild and wide stream that includes the gravel-sand transition. The Rapel dam operates about 25km upstream this second reach that is characterized by an 112m wall built in 1968. The Aconcagua hydropower system was characterized within a GIS environment and a morphological response conceptual model applied. The model uses two indexes to evaluate changes in i) channel forming discharge and ii) sediment supply. The provided response shows the trends and magnitudes of the changes, based in eighth possible directions for ten morphological responsible variables. The Rapel river system was evaluated differently and sampling of sediments characteristics (D50 and armour index), discharge index for both before and after the dam operation, Morphological Quality Index (IQM) and an analysis of aerial photography time series were performed. Results showed that the hydrology indicator impacts for the Aconcagua system were more severe than the impacts on sediments transport (typically the case for diversion type hydropower). A fine armour layer was found within the Rapel river site, also the IQM method classified it as poor quality, and the analysis of aerial photos showed three areas with significant changes in sinuosity. Although, both reaches indicated aggradation, attenuation in width, and an increment in slope. The amount and the quality of the available data on both reaches allowed assessing the basic morphological changes for the current rivers morphological stage. The next step is to transfer these methods and results to other systems that lack of these level of information, thus we could somehow diagnose and quantify impacts before the construction of the structure, and not as it is done today that impacts are not corrected within the project, but mitigated once the dam is in place and operating.

Feeding soy protein isolate and treatment with estradiol have different effects on mammary gland morphology and gene expression in weanling male and female rats

USDA-ARS?s Scientific Manuscript database

Isoflavones are phytochemical components of soy diets that bind weakly to estrogen receptors (ERs). To study potential estrogen-like actions of soy in the mammary gland during early development, we fed weanling male and female Sprague-Dawley rats a semi-purified diet with casein as the sole protein ...

Allometry of root branching and its relationship to root morphological and functional traits in three range grasses.

PubMed

Arredondo, J Tulio; Johnson, Douglas A

2011-11-01

The study of proportional relationships between size, shape, and function of part of or the whole organism is traditionally known as allometry. Examination of correlative changes in the size of interbranch distances (IBDs) at different root orders may help to identify root branching rules. Root morphological and functional characteristics in three range grasses {bluebunch wheatgrass [Pseudoroegneria spicata (Pursh) Löve], crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schult.×A. cristatum (L.) Gaert.], and cheatgrass (Bromus tectorum L.)} were examined in response to a soil nutrient gradient. Interbranch distances along the main root axis and the first-order laterals as well as other morphological and allocation root traits were determined. A model of nutrient diffusivity parameterized with root length and root diameter for the three grasses was used to estimate root functional properties (exploitation efficiency and exploitation potential). The results showed a significant negative allometric relationship between the main root axis and first-order lateral IBD (P ≤ 0.05), but only for bluebunch wheatgrass. The main root axis IBD was positively related to the number and length of roots, estimated exploitation efficiency of second-order roots, and specific root length, and was negatively related to estimated exploitation potential of first-order roots. Conversely, crested wheatgrass and cheatgrass, which rely mainly on root proliferation responses, exhibited fewer allometric relationships. Thus, the results suggested that species such as bluebunch wheatgrass, which display slow root growth and architectural root plasticity rather than opportunistic root proliferation and rapid growth, exhibit correlative allometry between the main axis IBD and morphological, allocation, and functional traits of roots.

Intra-specific variation in wing morphology and its impact on take-off performance in blue tits (Cyanistes caeruleus) during escape flights

PubMed Central

McFarlane, Laura; Altringham, John D.; Askew, Graham N.

2016-01-01

ABSTRACT Diurnal and seasonal increases in body mass and seasonal reductions in wing area may compromise a bird's ability to escape, as less of the power available from the flight muscles can be used to accelerate and elevate the animal's centre of mass. Here, we investigated the effects of intra-specific variation in wing morphology on escape take-off performance in blue tits (Cyanistes caeruleus). Flights were recorded using synchronised high-speed video cameras and take-off performance was quantified as the sum of the rates of change of the kinetic and potential energies of the centre of mass. Individuals with a lower wing loading, WL (WL=body weight/wing area) had higher escape take-off performance, consistent with the increase in lift production expected from relatively larger wings. Unexpectedly, it was found that the total power available from the flight muscles (estimated using an aerodynamic analysis) was inversely related to WL. This could simply be because birds with a higher WL have relatively smaller flight muscles. Alternatively or additionally, variation in the aerodynamic load on the wing resulting from differences in wing morphology will affect the mechanical performance of the flight muscles via effects on the muscle's length trajectory. Consistent with this hypothesis is the observation that wing beat frequency and relative downstroke duration increase with decreasing WL; both are factors that are expected to increase muscle power output. Understanding how wing morphology influences take-off performance gives insight into the potential risks associated with feather loss and seasonal and diurnal fluctuations in body mass. PMID:26994175

Genotypic and phenotypic evaluation of off-type grasses in hybrid Bermudagrass [Cynodon dactylon (L.) Pers. x C. transvaalensis Burtt-Davy] putting greens using genotyping-by-sequencing and morphological characterization.

PubMed

Reasor, Eric H; Brosnan, James T; Staton, Margaret E; Lane, Thomas; Trigiano, Robert N; Wadl, Phillip A; Conner, Joann A; Schwartz, Brian M

2018-01-01

Interspecific hybrid bermudagrass [ Cynodon dactylon (L.) Pers. x C. transvaalensis Burtt-Davy] is one of the most widely used grasses on golf courses, with cultivars derived from 'Tifgreen' or 'Tifdwarf' particularly used for putting greens. Many bermudagrass cultivars established for putting greens can be genetically unstable and lead to the occurrence of undesirable off-type grasses that vary in phenotype. The objective of this research was to genetically and phenotypically differentiate off-type grasses and hybrid cultivars. Beginning in 2013, off-type and desirable hybrid bermudagrass samples were collected from golf course putting greens in the southeastern United States and genetically and phenotypically characterized using genotyping-by-sequencing and morphology. Genotyping-by-sequencing determined that 11% (5) of off-type and desirable samples from putting greens were genetically divergent from standard cultivars such as Champion, MiniVerde, Tifdwarf, TifEagle, and Tifgreen. In addition, genotyping-by-sequencing was unable to genetically distinguish all standard cultivars from one another due to their similar origin and clonal propagation; however, over 90,000 potentially informative nucleotide variants were identified among the triploid hybrid cultivars. Although few genetic differences were found in this research, samples harvested from golf course putting greens had variable morphology and were clustered into three distinct phenotypic groups. The majority of off-type grasses in hybrid bermudagrass putting greens were genetically similar with variable morphological traits. Off-type grasses within golf course putting greens have the potential to compromise putting surface functionality and aesthetics.

Repeated Stand-Replacing Crown Fires Affect Seed Morphology and Germination in Aleppo pine.

PubMed

Saracino, Antonio; Bellino, Alessandro; Allevato, Emilia; Mingo, Antonio; Conti, Stefano; Rossi, Sergio; Bonanomi, Giuliano; Carputo, Domenico; Mazzoleni, Stefano

2017-01-01

Post-fire reproductive niche of Aleppo pine ( Pinus halepensis ) is deeply interlaced with fire products. Indeed, the high pH and low osmotic potentials of ash beds under burnt crowns constitute the main constraints to seed germination. In this study, we aim to investigate whether fire recurrence, through the physico-chemical constraints imposed by the ash beds, affects the reproduction ability of P. halepensis at the germination stage. To this aim, Aleppo pine seeds were collected in neighboring even-aged stands subjected to 0, 1, or 2 fires (namely fire cohorts), and seed morphology and germination performance, in terms of cumulative germination and germination kinetics, were studied under increasing osmotic potentials (from 0.0 to -1.2 MPa) and pH (from 6 to 11). Besides fire history, the role of ontogenetic age of mother plants on seed morphology and germination was also investigated. Differences in seed morphology among the three cohorts have been highlighted in a multivariate context, with anisotropic enlargement of the seeds produced by pine stands experiencing repeated fires. The patterns of seed germination varied primarily in relation to the fire cohort, with seeds from the pine stand experiencing repeated fires exhibiting enhanced tolerance to pH stress. Conversely, germination performances under osmotic constraints mainly depends on tree ontogenetic stage, with an involvement of fire history especially in the timing of seed germination. Our results suggest that, at least in the short term, fire recurrence does not constrain the reproduction ability of Aleppo pine. These results highlight the need for further research to elucidate the mechanisms behind these responses to recurrent fires.

Biological invasion of oxeye daisy (Leucanthemum vulgare) in North America: Pre-adaptation, post-introduction evolution, or both?

PubMed

Stutz, Sonja; Mráz, Patrik; Hinz, Hariet L; Müller-Schärer, Heinz; Schaffner, Urs

2018-01-01

Species may become invasive after introduction to a new range because phenotypic traits pre-adapt them to spread and become dominant. In addition, adaptation to novel selection pressures in the introduced range may further increase their potential to become invasive. The diploid Leucanthemum vulgare and the tetraploid L. ircutianum are native to Eurasia and have been introduced to North America, but only L. vulgare has become invasive. To investigate whether phenotypic differences between the two species in Eurasia could explain the higher abundance of L. vulgare in North America and whether rapid evolution in the introduced range may have contributed to its invasion success, we grew 20 L. vulgare and 21 L. ircutianum populations from Eurasia and 21 L. vulgare populations from North America under standardized conditions and recorded performance and functional traits. In addition, we recorded morphological traits to investigate whether the two closely related species can be clearly distinguished by morphological means and to what extent morphological traits have changed in L. vulgare post-introduction. We found pronounced phenotypic differences between L. vulgare and L. ircutianum from the native range as well as between L. vulgare from the native and introduced ranges. The two species differed significantly in morphology but only moderately in functional or performance traits that could have explained the higher invasion success of L. vulgare in North America. In contrast, leaf morphology was similar between L. vulgare from the native and introduced range, but plants from North America flowered later, were larger and had more and larger flower heads than those from Eurasia. In summary, we found litte evidence that specific traits of L. vulgare may have pre-adapted this species to become more invasive than L. ircutianum, but our results indicate that rapid evolution in the introduced range likely contributed to the invasion success of L. vulgare.

Gap Junctional Blockade Stochastically Induces Different Species-Specific Head Anatomies in Genetically Wild-Type Girardia dorotocephala Flatworms

PubMed Central

Emmons-Bell, Maya; Durant, Fallon; Hammelman, Jennifer; Bessonov, Nicholas; Volpert, Vitaly; Morokuma, Junji; Pinet, Kaylinnette; Adams, Dany S.; Pietak, Alexis; Lobo, Daniel; Levin, Michael

2015-01-01

The shape of an animal body plan is constructed from protein components encoded by the genome. However, bioelectric networks composed of many cell types have their own intrinsic dynamics, and can drive distinct morphological outcomes during embryogenesis and regeneration. Planarian flatworms are a popular system for exploring body plan patterning due to their regenerative capacity, but despite considerable molecular information regarding stem cell differentiation and basic axial patterning, very little is known about how distinct head shapes are produced. Here, we show that after decapitation in G. dorotocephala, a transient perturbation of physiological connectivity among cells (using the gap junction blocker octanol) can result in regenerated heads with quite different shapes, stochastically matching other known species of planaria (S. mediterranea, D. japonica, and P. felina). We use morphometric analysis to quantify the ability of physiological network perturbations to induce different species-specific head shapes from the same genome. Moreover, we present a computational agent-based model of cell and physical dynamics during regeneration that quantitatively reproduces the observed shape changes. Morphological alterations induced in a genomically wild-type G. dorotocephala during regeneration include not only the shape of the head but also the morphology of the brain, the characteristic distribution of adult stem cells (neoblasts), and the bioelectric gradients of resting potential within the anterior tissues. Interestingly, the shape change is not permanent; after regeneration is complete, intact animals remodel back to G. dorotocephala-appropriate head shape within several weeks in a secondary phase of remodeling following initial complete regeneration. We present a conceptual model to guide future work to delineate the molecular mechanisms by which bioelectric networks stochastically select among a small set of discrete head morphologies. Taken together, these data and analyses shed light on important physiological modifiers of morphological information in dictating species-specific shape, and reveal them to be a novel instructive input into head patterning in regenerating planaria. PMID:26610482

Examination of biogenic selenium-containing nanosystems based on polyelectrolyte complexes by atomic force, Kelvin probe force and electron microscopy methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sukhanova, T. E., E-mail: tat-sukhanova@mail.ru; Vylegzhanina, M. E.; Valueva, S. V.

The morphology and electrical properties of biogenic selenium-containing nanosystems based on polyelectrolyte complexes (PECs) were examined using AFM, Kelvin Probe Force and electron microscopy methods. It has been found, that prepared nanostructures significantly differed in their morphological types and parameters. In particular, multilayers capsules can be produced via varying synthesis conditions, especially, the selenium–PEC mass ratio ν. At the “special point” (ν = 0.1), filled and hollow nano- and microcapsules are formed in the system. The multilayer character of the capsules walls is visible in the phase images. Kelvin Probe Force images showed the inhomogeneity of potential distribution in capsulesmore » and outside them.« less

ECOPASS - a multivariate model used as an index of growth performance of poplar clones

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ceulemans, R.; Impens, I.

The model (ECOlogical PASSport) reported was constructed by principal component analysis from a combination of biochemical, anatomical/morphological and ecophysiological gas exchange parameters measured on 5 fast growing poplar clones. Productivity data were 10 selected trees in 3 plantations in Belgium and given as m.a.i.(b.a.). The model is shown to be able to reflect not only genetic origin and the relative effects of the different parameters of the clones, but also their production potential. Multiple regression analysis of the 4 principal components showed a high cumulative correlation (96%) between the 3 components related to ecophysiological, biochemical and morphological parameters, and productivity;more » the ecophysiological component alone correlated 85% with productivity.« less

EFFECTS OF PLATING DENSITY AND CULTURE TIME ON BONE MARROW STROMAL CELL CHARACTERISTICS

PubMed Central

Neuhuber, Birgit; Swanger, Sharon A.; Howard, Linda; Mackay, Alastair; Fischer, Itzhak

2008-01-01

Objective Bone marrow stromal cells (MSC) are multipotent adult stem cells that have emerged as promising candidates for cell therapy in disorders including cardiac infarction, stroke and spinal cord injury. While harvesting methods used by different laboratories are relatively standard, MSC culturing protocols vary widely. This study is aimed at evaluating the effects of initial plating density and total time in culture on proliferation, cell morphology, and differentiation potential of heterogeneous MSC cultures and more homogeneous cloned subpopulations. Methods Rat MSC were plated at 20, 200 and 2000 cells/cm2 and grown to 50% confluency. The numbers of population doublings and doubling times were determined within and across multiple passages. Changes in cell morphology and differentiation potential to adipogenic, chondrogenic, and osteogenic lineages were evaluated and compared among early, intermediate and late passages, as well as between heterogeneous and cloned MSC populations. Results We found optimal cell growth at a plating density of 200 cells/cm2. Cultures derived from all plating densities developed increased proportions of flat cells over time. Assays for chondrogenesis, osteogenesis and adipogenesis showed that heterogeneous MSC plated at all densities sustained the potential for all three mesenchymal phenotypes through at least passage 5; the flat subpopulation lost adipogenic and chondrogenic potential. Conclusion Our findings suggest that the initial plating density is not critical for maintaining a well-defined, multipotent MSC population. Time in culture, however, affects cell characteristics, suggesting that cell expansion should be limited, especially until the specific characteristics of different MSC subpopulations are better understood. PMID:18495329

Lineages with long durations are old and morphologically average: an analysis using multiple datasets.

PubMed

Liow, Lee Hsiang

2007-04-01

Lineage persistence is as central to biology as evolutionary change. Important questions regarding persistence include: why do some lineages outlive their relatives, neither becoming extinct nor evolving into separate lineages? Do these long-duration lineages have distinctive ecological or morphological traits that correlate with their geologic durations and potentially aid their survival? In this paper, I test the hypothesis that lineages (species and higher taxa) with longer geologic durations have morphologies that are more average than expected by chance alone. I evaluate this hypothesis for both individual lineages with longer durations and groups of lineages with longer durations, using more than 60 published datasets of animals with adequate fossil records. Analyses presented here show that groups of lineages with longer durations fall empirically into one of three theoretically possible scenarios, namely: (1) the morphology of groups of longer duration lineages is closer to the grand average of their inclusive group, that is, their relative morphological distance is smaller than expected by chance alone, when compared with rarified samples of their shorter duration relatives (a negative group morpho-duration distribution); (2) the relative morphological distance of groups of longer duration lineages is no different from rarified samples of their shorter duration relatives (a null group morpho-duration distribution); and (3) the relative morphological distance of groups of longer duration lineages is greater than expected when compared with rarified samples of their shorter duration relatives (a positive group morpho-duration distribution). Datasets exhibiting negative group morpho-duration distributions predominate. However, lineages with higher ranks in the Linnean hierarchy demonstrate positive morpho-duration distributions more frequently. The relative morphological distance of individual longer duration lineages is no different from that of rarified samples of their shorter duration relatives (a null individual morpho-duration distribution) for the majority of datasets studied. Contrary to the common idea that very persistent lineages are special or unique in some significant way, both the results from analyses of long-duration lineages as groups and individuals show that they are morphologically average. Persistent lineages often arise early in a group's history, even though there is no prior expectation for this tendency in datasets of extinct groups. The implications of these results for diversification histories and niche preemption are discussed.

Exceptional preservation reveals gastrointestinal anatomy and evolution in early actinopterygian fishes

PubMed Central

Argyriou, Thodoris; Clauss, Marcus; Maxwell, Erin E.; Furrer, Heinz; Sánchez-Villagra, Marcelo R.

2016-01-01

Current knowledge about the evolutionary morphology of the vertebrate gastrointestinal tract (GIT) is hindered by the low preservation potential of soft tissues in fossils. Exceptionally preserved cololites of individual †Saurichthys from the Middle Triassic of Switzerland provide unique insights into the evolutionary morphology of the GIT. The GIT of †Saurichthys differed from that of other early actinopterygians, and was convergent to that of some living sharks and rays, in exhibiting up to 30 turns of the spiral valve. Dissections and literature review demonstrate the phylogenetic diversity of GIT features and signs of biological factors that influence its morphology. A phylogenetically informed analysis of a dataset containing 134 taxa suggests that body size and phylogeny are important factors affecting the spiral valve turn counts. The high number of turns in the spiral valve of †Saurichthys and some recent sharks and rays reflect both energetically demanding lifestyles and the evolutionary histories of the groups. PMID:26732746

The influence of post-deposition annealing on the structure, morphology and luminescence properties of pulsed laser deposited La0.5Gd1.5SiO5 doped Dy3+ thin films

NASA Astrophysics Data System (ADS)

Ogugua, Simon N.; Swart, Hendrik C.; Ntwaeaborwa, Odireleng M.

2018-04-01

The influence of post-deposition annealing on the structure, particle morphology and photoluminescence properties of dysprosium (Dy3+) doped La0.5Gd1.5SiO5 thin films grown on Si(111) substrates at different substrate temperatures using pulsed laser deposition (PLD) technique were studied. The X-ray diffractometer results showed an improved crystallinity after post-annealing. The topography and morphology of the post-annealed films were studied using atomic force microscopy and field emission scanning electron microscopy respectively. The elemental composition in the surface region of the films were analyzed using energy dispersive X-ray spectroscopy. The photoluminescence studies showed an improved luminescent after post-annealing. The cathodoluminescence properties of the films are also reported. The CIE colour coordinates calculated from the photoluminescence and cathodoluminescence data suggest that the films can have potential application in white light emitting diode (LED) and field emission display (FED) applications.

Controlling the electrodeposition, morphology and structure of hydroxyapatite coating on 316L stainless steel.

PubMed

Thanh, Dinh Thi Mai; Nam, Pham Thi; Phuong, Nguyen Thu; Que, Le Xuan; Anh, Nguyen Van; Hoang, Thai; Lam, Tran Dai

2013-05-01

Hydroxyapatite (HAp) coatings were prepared on 316L stainless steel (316LSS) substrates by electrochemical deposition in the solutions containing Ca(NO3)2·4H2O and NH4H2PO4 at different electrolyte concentrations. Along with the effect of precursor concentration, the influence of temperature and H2O2 content on the morphology, structure and composition of the coating was thoroughly discussed with the help of X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectra. The in vitro tests in simulated body fluids (SBF) were carried out and then the morphological and structural changes were estimated by SEM and electrochemical techniques (open circuit potential, polarization curves, Nyquist and Bode spectra measurements). Being simple and cost-effective, this method is advantageous for producing HAp implant materials with good properties/characteristics, aiming towards in vivo biomedical applications. Copyright © 2013 Elsevier B.V. All rights reserved.

A comparative analysis of temporomandibular joint morphology in the African apes.

PubMed

Taylor, Andrea B

2005-06-01

A number of researchers have suggested a functional relationship between dietary variation and temporomandibular joint (TMJ) morphology, yet few studies have evaluated TMJ form in the African apes. In this study, I compare TMJ morphology in adults and during ontogeny in Gorilla (G.g. beringei, G.g. graueri, and G.g. gorilla) and Pan (P. paniscus, P. troglodytes troglodytes, P.t. schweinfurthii, and P.t. verus). I test two hypotheses: first, compared to all other African apes, G.g. beringei exhibits TMJ morphologies that would be predicted for a primate that consumes a diet comprised primarily of moderately to very tough, leafy vegetation; and second, all gorillas exhibit the same predicted morphologies compared to Pan. Compared to all adult African apes, G.g. beringei has higher rami and condyles positioned further above the occlusal plane of the mandible, relative to jaw length. Thus, mountain gorillas have the potential to generate relatively more muscle force, more evenly distribute occlusal forces along the postcanine teeth, and generate relatively greater jaw adductor moment. G.g. beringei also exhibits relatively wider mandibular condyles, suggesting these folivorous apes are able to resist relatively greater compressive loads along the lateral and/or medial aspect of the condyle. All gorillas likewise exhibit these same shape differences compared to Pan. These morphological responses are the predicted consequences of intensification of folivory and, as such, provide support for functional hypotheses linking these TMJ morphologies to degree of folivory. The African apes to not, however, demonstrate a systematic pattern of divergence in relative condylar area as a function of intensification of folivory. The ontogenetic trajectories for gorillas are significantly elevated above those of Pan, and to a lesser but still significant degree, mountain gorillas similarly deviate from lowland gorillas (G.g. gorilla and G.g. graueri). Thus, adult shape differences in ramal and condylar heights do not result from the simple extrapolation of common growth allometries relative to jaw length. As such, they are suggestive of an adaptive shift towards a tougher, more folivorous diet. However, the allometric patterning for condylar area and condylar width does not systematically conform to predictions based on dietary specialization. Thus, while differences in condylar shapes may confer functional advantages both during growth and as adults, there is no evidence to suggest selection for altered condylar proportions, independent of the effects of changes in jaw size.

Property Morphology Correlations of Organic Semiconductor Nanowires

NASA Astrophysics Data System (ADS)

McFarland, Frederick Marshall

Chemically doped and non-doped P3HT nanoaggregates are studied to establish a comprehensive understanding of the interplay between their morphology and various optoelectronic properties. One-dimensional nanoaggregates of P3HT are chosen as the model systems here due to their high surface/volume ratio and suitability for microscopic investigations. Atomic force microscopy (AFM) and kelvin probe force microscopy (KPFM) are used to correlate property/morphology characteristics of non-doped P3HT nanowhiskers. Topographical measurements indicate that individually folded P3HT motifs stack via interfacial interactions to form nanowhiskers in solution. Further aging leads to multi-layered nanowhiskers with greater stability and less instances of ?-? sliding of interfacial edge-on oriented motifs. KPFM measurements show higher surface potentials on portions of nanowhiskers containing local defects and stacking faults due to overlapping, and nanowhiskers that are at least triple-layered. Simultaneous UV-Vis and AFM characterizations compare the aggregation rates and morphologies of doped and non-doped P3HT nanowhiskers. Allowing fully solubilized P3HT to age without doping may produce high aspect ratio nanowhiskers containing disordered segments protruding out from the edges of the nanowhiskers. These protruding segments could also serve as "tie-molecules" between adjacent nanowhiskers. Doping fully solubilized P3HT will lead to substantially higher rates of P3HT aggregation. Doped nanowhiskers also display different morphologies. They pack tighter, are smoother, and are thicker and higher versus non-doped nanowhiskers, indicating a different aggregation mechanism. Stopped flow-kinetics was employed to investigate the reactivity of two distinctively different morphological forms of P3HT towards dopants. Fully solubilized P3HT undergoes a slow doping mechanism whereas pre-aggregated P3HT undergoes a fast doping mechanism. Pseudo-single reactant rate fittings indicate that both mechanisms appear to be 1st order in P3HT, whereby pre-aggregated P3HT mixtures will produce more doped products per P3HT monomer unit than fully solubilized P3HT. This study highlights the impact of conjugated polymer's morphology on their doping efficiency. Density functional theory was used to investigate the charge transfer (CT) states between oligothiophene and F4-TCNQ. CT of several unreported complexes that feature two oligomers stacked in a sandwich or layered configuration is investigated. Our preliminary results suggest that these new complexes can generate substantially more charge per F4-TCNQ than previously reported.

Piscivory limits diversification of feeding morphology in centrarchid fishes.

PubMed

Collar, David C; O'Meara, Brian C; Wainwright, Peter C; Near, Thomas J

2009-06-01

Proximity to an adaptive peak influences a lineage's potential to diversify. We tested whether piscivory, a high quality but functionally demanding trophic strategy, represents an adaptive peak that limits morphological diversification in the teleost fish clade, Centrarchidae. We synthesized published diet data and applied a well-resolved, multilocus and time-calibrated phylogeny to reconstruct ancestral piscivory. We measured functional features of the skull and performed principal components analysis on species' values for these variables. To assess the role of piscivory on morphological diversification, we compared the fit of several models of evolution for each principal component (PC), where model parameters were allowed to vary between lineages that differed in degree of piscivory. According to the best-fitting model, two adaptive peaks influenced PC 1 evolution, one peak shared between highly and moderately piscivorous lineages and another for nonpiscivores. Brownian motion better fit PCs 2, 3, and 4, but the best Brownian models infer a slow rate of PC 2 evolution shared among all piscivores and a uniquely slow rate of PC 4 evolution in highly piscivorous lineages. These results suggest that piscivory limits feeding morphology diversification, but this effect is most severe in lineages that exhibit an extreme form of this diet.

Strong texturing of lithium metal in batteries

DOE PAGES

Shi, Feifei; Pei, Allen; Vailionis, Arturas; ...

2017-10-30

Lithium, with its high theoretical specific capacity and lowest electrochemical potential, has been recognized as the ultimate negative electrode material for next-generation lithium-based high-energy-density batteries. However, a key challenge that has yet to be overcome is the inferior reversibility of Li plating and stripping, typically thought to be related to the uncontrollable morphology evolution of the Li anode during cycling. Here we show that Li-metal texturing (preferential crystallographic orientation) occurs during electrochemical deposition, which governs the morphological change of the Li anode. X-ray diffraction pole-figure analysis demonstrates that the texture of Li deposits is primarily dependent on the type ofmore » additive or cross-over molecule from the cathode side. With adsorbed additives, like LiNO 3 and polysulfide, the lithium deposits are strongly textured, with Li (110) planes parallel to the substrate, and thus exhibit uniform, rounded morphology. A growth diagram of lithium deposits is given to connect various texture and morphology scenarios for different battery electrolytes. In conclusion, this understanding of lithium electrocrystallization from the crystallographic point of view provides significant insight for future lithium anode materials design in high-energy-density batteries.« less

Strong texturing of lithium metal in batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shi, Feifei; Pei, Allen; Vailionis, Arturas

Lithium, with its high theoretical specific capacity and lowest electrochemical potential, has been recognized as the ultimate negative electrode material for next-generation lithium-based high-energy-density batteries. However, a key challenge that has yet to be overcome is the inferior reversibility of Li plating and stripping, typically thought to be related to the uncontrollable morphology evolution of the Li anode during cycling. Here we show that Li-metal texturing (preferential crystallographic orientation) occurs during electrochemical deposition, which governs the morphological change of the Li anode. X-ray diffraction pole-figure analysis demonstrates that the texture of Li deposits is primarily dependent on the type ofmore » additive or cross-over molecule from the cathode side. With adsorbed additives, like LiNO 3 and polysulfide, the lithium deposits are strongly textured, with Li (110) planes parallel to the substrate, and thus exhibit uniform, rounded morphology. A growth diagram of lithium deposits is given to connect various texture and morphology scenarios for different battery electrolytes. In conclusion, this understanding of lithium electrocrystallization from the crystallographic point of view provides significant insight for future lithium anode materials design in high-energy-density batteries.« less

Emerging principles of regulatory evolution.

PubMed

Prud'homme, Benjamin; Gompel, Nicolas; Carroll, Sean B

2007-05-15

Understanding the genetic and molecular mechanisms governing the evolution of morphology is a major challenge in biology. Because most animals share a conserved repertoire of body-building and -patterning genes, morphological diversity appears to evolve primarily through changes in the deployment of these genes during development. The complex expression patterns of developmentally regulated genes are typically controlled by numerous independent cis-regulatory elements (CREs). It has been proposed that morphological evolution relies predominantly on changes in the architecture of gene regulatory networks and in particular on functional changes within CREs. Here, we discuss recent experimental studies that support this hypothesis and reveal some unanticipated features of how regulatory evolution occurs. From this growing body of evidence, we identify three key operating principles underlying regulatory evolution, that is, how regulatory evolution: (i) uses available genetic components in the form of preexisting and active transcription factors and CREs to generate novelty; (ii) minimizes the penalty to overall fitness by introducing discrete changes in gene expression; and (iii) allows interactions to arise among any transcription factor and downstream CRE. These principles endow regulatory evolution with a vast creative potential that accounts for both relatively modest morphological differences among closely related species and more profound anatomical divergences among groups at higher taxonomical levels.

Cell wall staining with Trypan blue enables quantitative analysis of morphological changes in yeast cells.

PubMed

Liesche, Johannes; Marek, Magdalena; Günther-Pomorski, Thomas

2015-01-01

Yeast cells are protected by a cell wall that plays an important role in the exchange of substances with the environment. The cell wall structure is dynamic and can adapt to different physiological states or environmental conditions. For the investigation of morphological changes, selective staining with fluorescent dyes is a valuable tool. Furthermore, cell wall staining is used to facilitate sub-cellular localization experiments with fluorescently-labeled proteins and the detection of yeast cells in non-fungal host tissues. Here, we report staining of Saccharomyces cerevisiae cell wall with Trypan Blue, which emits strong red fluorescence upon binding to chitin and yeast glucan; thereby, it facilitates cell wall analysis by confocal and super-resolution microscopy. The staining pattern of Trypan Blue was similar to that of the widely used UV-excitable, blue fluorescent cell wall stain Calcofluor White. Trypan Blue staining facilitated quantification of cell size and cell wall volume when utilizing the optical sectioning capacity of a confocal microscope. This enabled the quantification of morphological changes during growth under anaerobic conditions and in the presence of chemicals, demonstrating the potential of this approach for morphological investigations or screening assays.

Bio-inspired scale-like surface textures and their tribological properties.

PubMed

Greiner, Christian; Schäfer, Michael

2015-06-30

Friction, wear and the associated energy dissipation are major challenges in all systems containing moving parts. Examples range from nanoelectromechanical systems over hip prosthesis to off-shore wind turbines. Bionic approaches have proven to be very successful in many engineering problems, while investigating the potential of a bio-inspired approach in creating morphological surface textures is a relatively new field of research. Here, we developed laser-created textures inspired by the scales found on the skin of snakes and certain lizards. We show that this bio-inspired surface morphology reduced dry sliding friction forces by more than 40%. In lubricated contacts the same morphology increased friction by a factor of three. Two different kinds of morphologies, one with completely overlapping scales and one with the scales arranged in individual rows, were chosen. In lubricated as well as unlubricated contacts, the surface texture with the scales in rows showed lower friction forces than the completely overlapping ones. We anticipate that these results could have significant impact in all dry sliding contacts, ranging from nanoelectromechanical and micro-positioning systems up to large-scale tribological contacts which cannot be lubricated, e.g. because they are employed in a vacuum environment.

A comparative evaluation of semen parameters in pre- and post-Hurricane Katrina human population.

PubMed

Baran, Caner; Hellstrom, Wayne J; Sikka, Suresh C

2015-01-01

A natural disaster leading to accumulation of environmental contaminants may have substantial effects on the male reproductive system. Our aim was to compare and assess semen parameters in a normospermic population residing in the Southern Louisiana, USA area pre- and post-Hurricane Katrina. We retrospectively evaluated semen analyses data (n = 3452) of 1855 patients who attended the Tulane University Andrology/Fertility Clinic between 1999 and 2013. The study inclusion criteria were men whose semen analyses showed ≥ 1.5 ml volume; ≥15 million ml -1 sperm concentration; ≥39 million total sperm count; ≥40% motility; >30% morphology, with an abstinence interval of 2-7 days. After the inclusion criteria applied to the population, 367 normospermic patients were included in the study. Descriptive statistics and group-based analyses were performed to interpret the differences between the pre-Katrina (Group 1, 1999-2005) and the post-Katrina (Group 2, 2006-2013) populations. There were significant differences in motility, morphology, number of white blood cell, immature germ cell count, pH and presence of sperm agglutination, but surprisingly there were no significant differences in sperm count between the two populations. This long-term comparative analysis further documents that a major natural disaster with its accompanied environmental issues can influence certain semen parameters (e.g., motility and morphology) and, by extension, fertility potential of the population of such areas.

Investigations on diamond nanostructuring of different morphologies by the reactive-ion etching process and their potential applications.

PubMed

Kunuku, Srinivasu; Sankaran, Kamatchi Jothiramalingam; Tsai, Cheng-Yen; Chang, Wen-Hao; Tai, Nyan-Hwa; Leou, Keh-Chyang; Lin, I-Nan

2013-08-14

We report the systematic studies on the fabrication of aligned, uniform, and highly dense diamond nanostructures from diamond films of various granular structures. Self-assembled Au nanodots are used as a mask in the self-biased reactive-ion etching (RIE) process, using an O2/CF4 process plasma. The morphology of diamond nanostructures is a close function of the initial phase composition of diamond. Cone-shaped and tip-shaped diamond nanostructures result for microcrystalline diamond (MCD) and nanocrystalline diamond (NCD) films, whereas pillarlike and grasslike diamond nanostructures are obtained for Ar-plasma-based and N2-plasma-based ultrananocrystalline diamond (UNCD) films, respectively. While the nitrogen-incorporated UNCD (N-UNCD) nanograss shows the most-superior electron-field-emission properties, the NCD nanotips exhibit the best photoluminescence properties, viz, different applications need different morphology of diamond nanostructures to optimize the respective characteristics. The optimum diamond nanostructure can be achieved by proper choice of granular structure of the initial diamond film. The etching mechanism is explained by in situ observation of optical emission spectrum of RIE plasma. The preferential etching of sp(2)-bonded carbon contained in the diamond films is the prime factor, which forms the unique diamond nanostructures from each type of diamond films. However, the excited oxygen atoms (O*) are the main etching species of diamond film.

Non-invasive assessment of culture media from goat cloned embryos associated with subjective morphology by gas chromatography - mass spectroscopy-based metabolomic analysis.

PubMed

Zhang, Yan-Li; Zhang, Guo-Min; Jia, Ruo-Xin; Wan, Yong-Jie; Yang, Hua; Sun, Ling-Wei; Han, Le; Wang, Feng

2018-01-01

Pre-implantation embryo metabolism demonstrates distinctive characteristics associated with the development potential of embryos. We aim to determine if metabolic differences correlate with embryo morphology. In this study, gas chromatography - mass spectroscopy (GC-MS)-based metabolomics was used to assess the culture media of goat cloned embryos collected from high-quality (HQ) and low-quality (LQ) groups based on morphology. Expression levels of amino acid transport genes were further examined by quantitative real-time PCR. Results showed that the HQ group presented higher percentages of blastocysts compared with the LQ counterparts (P < 0.05). Metabolic differences were also present between HQ and LQ groups. The culture media of the HQ group showed lower levels of valin, lysine, glutamine, mannose and acetol, and higher levels of glucose, phytosphingosine and phosphate than those of the LQ group. Additionally, expression levels of amino acid transport genes SLC1A5 and SLC3A2 were significantly lower in the HQ group than the LQ group (P < 0.05, respectively). To our knowledge, this is the first report which uses GC-MS to detect metabolic differences in goat cloned embryo culture media. The biochemical profiles may help to select the most in vitro viable embryos. © 2017 Japanese Society of Animal Science.

Impact of head morphology on local brain specific absorption rate from exposure to mobile phone radiation.

PubMed

Adibzadeh, Fatemeh; Bakker, Jurriaan F; Paulides, Margarethus M; Verhaart, René F; van Rhoon, Gerard C

2015-01-01

Among various possible health effects of mobile phone radiation, the risk of inducing cancer has the strongest interest of laymen and health organizations. Recently, the Interphone epidemiological study investigated the association between the estimated Radio Frequency (RF) dose from mobile phones and the risk of developing a brain tumor. Their dosimetric analysis included over 100 phone models but only two homogeneous head phantoms. So, the potential impact of individual morphological features on global and local RF absorption in the brain was not investigated. In this study, we performed detailed dosimetric simulations for 20 head models and quantified the variation of RF dose in different brain regions as a function of head morphology. Head models were exposed to RF fields from generic mobile phones at 835 and 1900 MHz in the "tilted" and "cheek" positions. To evaluate the local RF dose variation, we used and compared two different post-processing methods, that is, averaging specific absorption rate (SAR) over Talairach regions and over sixteen predefined 1 cm(3) cube-shaped field-sensors. The results show that the variation in the averaged SAR among the heads can reach up to 16.4 dB at a 1 cm(3) cube inside the brain (field-sensor method) and alternatively up to 15.8 dB in the medulla region (Talairach method). In conclusion, we show head morphology as an important uncertainty source for dosimetric studies of mobile phones. Therefore, any dosimetric analysis dealing with RF dose at a specific region in the brain (e.g., tumor risk analysis) should be based upon real morphology. © 2014 Wiley Periodicals, Inc.

Splitting of IVP bovine blastocyst affects morphology and gene expression of resulting demi-embryos during in vitro culture and in vivo elongation.

PubMed

Velasquez, Alejandra E; Castro, Fidel O; Veraguas, Daniel; Cox, Jose F; Lara, Evelyn; Briones, Mario; Rodriguez-Alvarez, Lleretny

2016-02-01

Embryo splitting might be used to increase offspring yield and for molecular analysis of embryo competence. How splitting affects developmental potential of embryos is unknown. This research aimed to study the effect of bovine blastocyst splitting on morphological and gene expression homogeneity of demi-embryos and on embryo competence during elongation. Grade I bovine blastocyst produced in vitro were split into halves and distributed in nine groups (3 × 3 setting according to age and stage before splitting; age: days 7-9; stage: early, expanded and hatched blastocysts). Homogeneity and survival rate in vitro after splitting (12 h, days 10 and 13) and the effect of splitting on embryo development at elongation after embryo transfer (day 17) were assessed morphologically and by RT-qPCR. The genes analysed were OCT4, SOX2, NANOG, CDX2, TP1, TKDP1, EOMES, and BAX. Approximately 90% of split embryos had a well conserved defined inner cell mass (ICM), 70% of the halves had similar size with no differences in gene expression 12 h after splitting. Split embryos cultured further conserved normal and comparable morphology at day 10 of development; this situation changes at day 13 when embryo morphology and gene expression differed markedly among demi-embryos. Split and non-split blastocysts were transferred to recipient cows and were recovered at day 17. Fifty per cent of non-split embryos were larger than 100 mm (33% for split embryos). OCT4, SOX2, TP1 and EOMES levels were down-regulated in elongated embryos derived from split blastocysts. In conclusion, splitting day-8 blastocysts yields homogenous demi-embryos in terms of developmental capability and gene expression, but the initiation of the filamentous stage seems to be affected by the splitting.

Hippocampal Astrocytes in Migrating and Wintering Semipalmated Sandpiper Calidris pusilla.

PubMed

Carvalho-Paulo, Dario; de Morais Magalhães, Nara G; de Almeida Miranda, Diego; Diniz, Daniel G; Henrique, Ediely P; Moraes, Isis A M; Pereira, Patrick D C; de Melo, Mauro A D; de Lima, Camila M; de Oliveira, Marcus A; Guerreiro-Diniz, Cristovam; Sherry, David F; Diniz, Cristovam W P

2017-01-01

Seasonal migratory birds return to the same breeding and wintering grounds year after year, and migratory long-distance shorebirds are good examples of this. These tasks require learning and long-term spatial memory abilities that are integrated into a navigational system for repeatedly locating breeding, wintering, and stopover sites. Previous investigations focused on the neurobiological basis of hippocampal plasticity and numerical estimates of hippocampal neurogenesis in birds but only a few studies investigated potential contributions of glial cells to hippocampal-dependent tasks related to migration. Here we hypothesized that the astrocytes of migrating and wintering birds may exhibit significant morphological and numerical differences connected to the long-distance flight. We used as a model the semipalmated sandpiper Calidris pusilla , that migrates from northern Canada and Alaska to South America. Before the transatlantic non-stop long-distance component of their flight, the birds make a stopover at the Bay of Fundy in Canada. To test our hypothesis, we estimated total numbers and compared the three-dimensional (3-D) morphological features of adult C. pusilla astrocytes captured in the Bay of Fundy ( n = 249 cells) with those from birds captured in the coastal region of Bragança, Brazil, during the wintering period ( n = 250 cells). Optical fractionator was used to estimate the number of astrocytes and for 3-D reconstructions we used hierarchical cluster analysis. Both morphological phenotypes showed reduced morphological complexity after the long-distance non-stop flight, but the reduction in complexity was much greater in Type I than in Type II astrocytes. Coherently, we also found a significant reduction in the total number of astrocytes after the transatlantic flight. Taken together these findings suggest that the long-distance non-stop flight altered significantly the astrocytes population and that morphologically distinct astrocytes may play different physiological roles during migration.

Putting prey back together again: integrating predator-induced behavior, morphology, and life history.

PubMed

Hoverman, Jason T; Auld, Josh R; Relyea, Rick A

2005-07-01

The last decade has seen an explosion in the number of studies exploring predator-induced plasticity. Recently, there has been a call for more comprehensive approaches that can identify functional relationships between traits, constraints on phenotypic responses, and the cost and benefits of alternative phenotypes. In this study, we exposed Helisoma trivolvis, a freshwater snail, to a factorial combination of three resource levels and five predator environments (no predator, one or two water bugs, and one or two crayfish) and examined ten traits including behavior, morphology, and life history. Each predator induced a unique suite of behavioral and morphological responses. Snails increased near-surface habitat use with crayfish but not with water bugs. Further, crayfish induced narrow and high shells whereas water bugs induced wide shells and wide apertures. In terms of life history, both predators induced delayed reproduction and greater mass at reproduction. However, crayfish induced a greater delay in reproduction that resulted in reduced fecundity whereas water bugs did not induce differences in fecundity. Resource levels impacted the morphology of H. trivolvis; snails reared with greater resource levels produced higher shells, narrower shells, and wider apertures. Resource levels also impacted snail life history; lower resources caused longer times to reproduction and reduced fecundity. Based on an analysis of phenotypic correlations, the morphological responses to each predator most likely represent phenotypic trade-offs. Snails could either produce invasion-resistant shells for defense against water bugs or crush-resistant shells for defense against crayfish, but not both. Our use of a comprehensive approach to examine the responses of H. trivolvis has provided important information regarding the complexity of phenotypic responses to different environments, the patterns of phenotypic integration across environments, and the potential costs and benefits associated with plastic traits.

[A new herbs traceability method based on DNA barcoding-origin-morphology analysis--an example from an adulterant of 'Heiguogouqi'].

PubMed

Gu, Xuan; Zhang, Xiao-qin; Song, Xiao-na; Zang, Yi-mei; Li Yan-peng; Ma, Chang-hua; Zhao, Bai-xiao; Liu, Chun-sheng

2014-12-01

The fruit of Lycium ruthenicum is a common folk medicine in China. Now it is popular for its antioxidative effect and other medical functions. The adulterants of the herb confuse consumers. In order to identify a new adulterant of L. ruthenicum, a research was performed based on NCBI Nucleotide Database ITS Sequence, combined analysis of the origin and morphology of the adulterant to traceable varieties. Total genomic DNA was isolated from the materials, and nuclear DNA ITS sequences were amplified and sequenced; DNA fragments were collated and matched by using ContingExpress. Similarity identification of BLAST analysis was performed. Besides, the distribution of plant origin and morphology were considered to further identification and verification. Families and genera were identified by molecular identification method. The adulterant was identified as plant belonging to Berberis. Origin analysis narrowed the range of sample identification. Seven different kinds of plants in Berberis were potential sources of the sample. Adulterants variety was traced by morphological analysis. The united molecular identification-origin-morphology research proves to be a preceding way to medical herbs traceability with time-saving and economic advantages and the results showed the new adulterant of L. ruthenicum was B. kaschgarica. The main differences between B. kaschgarica and L. ruthenicum are as follows: in terms of the traits, the surface of B. kaschgarica is smooth and crispy, and that of L. ruthenicum is shrinkage, solid and hard. In microscopic characteristics, epicarp cells of B. aschgarica thickening like a string of beads, stone cells as the rectangle, and the stone cell walls of L. ruthenicum is wavy, obvious grain layer. In molecular sequences, the length of ITS sequence of B. kaschgarica is 606 bp, L. ruthenicum is 654 bp, the similarity of the two sequences is 53.32%.

Channel-shoal morphodynamics in response to distinct hydrodynamic drivers at the outer Weser estuary

NASA Astrophysics Data System (ADS)

Herrling, Gerald; Benninghoff, Markus; Zorndt, Anna; Winter, Christian

2017-04-01

The interaction of tidal, wave and wind forces primarily governs the morphodynamics of intertidal channel-shoal systems. Typical morphological changes comprise tidal channel meandering and/or migration with related shoal erosion or accretion. These intertidal flat systems are likely to response to accelerated sea level rise and to potential changes in storm frequency and direction. The aim of the ongoing research project is an evaluation of outer estuarine channel-shoal dynamics by combining the analysis of morphological monitoring data with high-resolution morphodynamic modelling. A focus is set on their evolution in reaction to different hydrodynamic forcings like tides, wind driven currents, waves under fair-weather and high energy conditions, and variable upstream discharges. As an example the Outer Weser region was chosen, and a tidal channel system serves as a reference site: Availability of almost annual bathymetrical observations of an approx. 10 km long tidal channel (Fedderwarder Priel) and its morphological development largely independent from maintenance dredging of the main Weser navigational channel make this tributary an ideal study area. The numerical modelling system Delft3D (Deltares) is applied to run real-time annual scenario simulations aiming to evaluate and to differentiate the morphological responses to distinct hydrodynamic drivers. A comprehensive morphological analysis of available observations at the FWP showed that the channel migration trends and directions are persistent at particular channel bends and meanders for the considered period of 14 years. Migration trends and directions are well reproduced by one-year model simulations. Morphodynamic modelling is applied to interpolate between observations and relate sediment dynamics to different forcing scenarios in the outer Weser estuary as a whole and at the scale of local tributary channels and flats.

Transpiration and CO/sub 2/ fixation of selected desert shrubs as related to soil-water potential

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, S.B.; Letey, J. Jr.; Lunt, O.R.

1980-01-01

In desert plants, transpiration rates decreased before photosynthetic rates when plants were entering a period of water stress. This may have adaptive consequences. A difference of -5 bars in the soil-moisture potential had considerable importance in reducing the rate of transpiration. In Helianthus annuus L. (sunflower) the photosynthetic rate decreased before the transpiration rate in contrast to Great Basin-Mojave Desert plants, and the changes occurred with a -1 bar difference in soil-moisture potential. Morphological changes in three desert plant species (Artemisia tridentata Nutt., Ambrosia dumosa (Gray) Payne, Larrea tridentata (Ses. Moc. ex DC) Cov.) as the soil-moisture potential decreased aremore » given. With a mesic species, H. annuus, 20% reduction in photosynthesis and transpiration was reached at higher soil-moisture potentials than with the desert plants. Loss of net photosynthesis occurred in A. dumosa (a summer deciduous shrub) as PSI soil reached -48 bars in the field, whereas L. tridentata (an evergreen shrub) at the same time was able to maintain a water potential difference between soil and plant of -10 to -15 bars and continue net CO/sub 2/ gain well into the summer months.« less

Marine Phages As Tracers: Effects of Size, Morphology, and Physico-Chemical Surface Properties on Transport in a Porous Medium.

PubMed

Ghanem, Nawras; Kiesel, Bärbel; Kallies, René; Harms, Hauke; Chatzinotas, Antonis; Wick, Lukas Y

2016-12-06

Although several studies examined the transport of viruses in terrestrial systems only few studies exist on the use of marine phages (i.e., nonterrestrial viruses infecting marine host bacteria) as sensitively detectable microbial tracers for subsurface colloid transport and water flow. Here, we systematically quantified and compared for the first time the effects of size, morphology and physicochemical surface properties of six marine phages and two coliphages (MS2, T4) on transport in sand-filled percolated columns. Phage-sand interactions were described by colloidal filtration theory and the extended Derjaguin-Landau-Verwey-Overbeek approach (XDLVO), respectively. The phages belonged to different families and comprised four phages never used in transport studies (i.e., PSA-HM1, PSA-HP1, PSA-HS2, and H3/49). Phage transport was influenced by size, morphology and hydrophobicity in an approximate order of size > hydrophobicity ≥ morphology. Two phages PSA-HP1, PSA-HS2 (Podoviridae and Siphoviridae) exhibited similar mass recovery as commonly used coliphage MS2 and were 7-fold better transported than known marine phage vB_PSPS-H40/1. Differing properties of the marine phages may be used to trace transport of indigenous viruses, natural colloids or anthropogenic nanomaterials and, hence, contribute to better risk analysis. Our results underpin the potential role of marine phages as microbial tracer for transport of colloidal particles and water flow.

A morphometric system to distinguish sheep and goat postcranial bones

PubMed Central

2017-01-01

Distinguishing between the bones of sheep and goat is a notorious challenge in zooarchaeology. Several methodological contributions have been published at different times and by various people to facilitate this task, largely relying on a macro-morphological approach. This is now routinely adopted by zooarchaeologists but, although it certainly has its value, has also been shown to have limitations. Morphological discriminant criteria can vary in different populations and correct identification is highly dependent upon a researcher’s experience, availability of appropriate reference collections, and many other factors that are difficult to quantify. There is therefore a need to establish a more objective system, susceptible to scrutiny. In order to fulfil such a requirement, this paper offers a comprehensive morphometric method for the identification of sheep and goat postcranial bones, using a sample of more than 150 modern skeletons as a basis, and building on previous pioneering work. The proposed method is based on measurements—some newly created, others previously published–and its use is recommended in combination with the more traditional morphological approach. Measurement ratios, used to translate morphological traits into biometrical attributes, are demonstrated to have substantial diagnostic potential, with the vast majority of specimens correctly assigned to species. The efficacy of the new method is also tested with Discriminant Analysis, which provides a successful verification of the biometrical indices, a statistical means to select the most promising measurements, and an additional line of analysis to be used in conjunction with the others. PMID:28594831

A morphometric system to distinguish sheep and goat postcranial bones.

PubMed

Salvagno, Lenny; Albarella, Umberto

2017-01-01

Distinguishing between the bones of sheep and goat is a notorious challenge in zooarchaeology. Several methodological contributions have been published at different times and by various people to facilitate this task, largely relying on a macro-morphological approach. This is now routinely adopted by zooarchaeologists but, although it certainly has its value, has also been shown to have limitations. Morphological discriminant criteria can vary in different populations and correct identification is highly dependent upon a researcher's experience, availability of appropriate reference collections, and many other factors that are difficult to quantify. There is therefore a need to establish a more objective system, susceptible to scrutiny. In order to fulfil such a requirement, this paper offers a comprehensive morphometric method for the identification of sheep and goat postcranial bones, using a sample of more than 150 modern skeletons as a basis, and building on previous pioneering work. The proposed method is based on measurements-some newly created, others previously published-and its use is recommended in combination with the more traditional morphological approach. Measurement ratios, used to translate morphological traits into biometrical attributes, are demonstrated to have substantial diagnostic potential, with the vast majority of specimens correctly assigned to species. The efficacy of the new method is also tested with Discriminant Analysis, which provides a successful verification of the biometrical indices, a statistical means to select the most promising measurements, and an additional line of analysis to be used in conjunction with the others.

Induction of temporally dissociated morphological and physiological differentiation of N1E-115 cells.

PubMed

Cosgrove, C; Cobbett, P

1991-07-01

Clonal cells derived from neural tumors have been widely used to study the processes of neuronal differentiation in vitro. The murine neuroblastoma clone N1E-115 has recently been shown to differentiate morphologically in response to removal of serum from the culture medium. In the present study, the nature and time course of electrophysiological differentiation of N1E-115 cells maintained in serum-free medium was examined. Differentiated cells had a higher resting potential and lower input conductance than nondifferentiated cells. Differentiated but not nondifferentiated cells generated current evoked action potentials, and differentiated cells fired spontaneous, repetitive action potentials after 13 days in serum-free medium. The rate of potential change during the depolarizing and repolarizing phases of the action potential became faster as the duration of maintenance of cells in serum-free medium increased. Remarkably, morphological differentiation appeared to be complete after exposure to serum-free medium for 5 days but electrophysiological differentiation was not complete until 13 days in this medium.

Review of Fabrication Methods, Physical Properties, and Applications of Nanostructured Copper Oxides Formed via Electrochemical Oxidation.

PubMed

Stepniowski, Wojciech J; Misiolek, Wojciech Z

2018-05-29

Typically, anodic oxidation of metals results in the formation of hexagonally arranged nanoporous or nanotubular oxide, with a specific oxidation state of the transition metal. Recently, the majority of transition metals have been anodized; however, the formation of copper oxides by electrochemical oxidation is yet unexplored and offers numerous, unique properties and applications. Nanowires formed by copper electrochemical oxidation are crystalline and composed of cuprous (CuO) or cupric oxide (Cu₂O), bringing varied physical and chemical properties to the nanostructured morphology and different band gaps: 1.44 and 2.22 eV, respectively. According to its Pourbaix (potential-pH) diagram, the passivity of copper occurs at ambient and alkaline pH. In order to grow oxide nanostructures on copper, alkaline electrolytes like NaOH and KOH are used. To date, no systemic study has yet been reported on the influence of the operating conditions, such as the type of electrolyte, its temperature, and applied potential, on the morphology of the grown nanostructures. However, the numerous reports gathered in this paper will provide a certain view on the matter. After passivation, the formed nanostructures can be also post-treated. Post-treatments employ calcinations or chemical reactions, including the chemical reduction of the grown oxides. Nanostructures made of CuO or Cu₂O have a broad range of potential applications. On one hand, with the use of surface morphology, the wetting contact angle is tuned. On the other hand, the chemical composition (pure Cu₂O) and high surface area make such materials attractive for renewable energy harvesting, including water splitting. While compared to other fabrication techniques, self-organized anodization is a facile, easy to scale-up, time-efficient approach, providing high-aspect ratio one-dimensional (1D) nanostructures. Despite these advantages, there are still numerous challenges that have to be faced, including the strict control of the chemical composition and morphology of the grown nanostructures, their uniformity, and understanding the mechanism of their growth.

Low temperature–scanning electron microscopy to evaluate morphology and predation of Scolothrips sexmaculatus Pergande (Thysanoptera: Thripidae) against spider mites (Acari: Tetranychidae: Tetranychus species)

USDA-ARS?s Scientific Manuscript database

This paper evaluates the potential usefulness of low temperature-scanning electron microscopy (LT-SEM) to evaluate morphology and predation behavior of the six-spotted thrips (Scolothrips sexmaculatus Pergande) against the two-spotted spider mite (Tetranychus urticae (Koch)). Morphological features...

Novel Nano-Composite Catalysts for Renewable Energy Storage Applications

NASA Astrophysics Data System (ADS)

Devaguptapu, Surya Vamsi

Spinel NiCo2O4 catalysts are considered the promising precious metal-free catalyst for oxygen reactions. Significant efforts are mainly explore optimal chemical doping and substituent to tune its electronic structures for enhanced performance. Here, we focuses on morphology control and determine the morphology-dependent activity for bifunctional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). In particular, three types of spinel NiCo2O4 were prepared using temple-free, SiO 2 hard template, and Pluronic-123 soft template hydrothermal methods, showing significantly different morphologies, respectively. In particular, template-free method yield dense structures. Sold-template method assists the formation of porous and hollow structures. Importantly, the soft template is effective to prepare a unique nanoflower morphology containing abundant rose petal (needle) like structures. The effect of the utilization of templates, both soft and hard as well as a template free synthesis on the morphology as well as the activity and stability of the final catalyst is investigated. Compared to others, the nanoflower-like NiCo2O4 exhibited the highest bifunctional catalytic activity simultaneously for ORR and OER, likely due to the facile absorption of oxygen molecules on increased surface areas with efficient mass transfer. The nanoflower NiCo2O 4 also exhibited an onset and half-wave potentials of 0.94 and 0.82 V for the ORR in alkaline media. Although it is still inferior to state of the art Pt, the new type of spinel NiCo2O4 catalyst represents the best activity compared to reported carbon-free oxides. Meanwhile, OER activity and stability were achieved with an onset potential of 1.48 V generating a current density of 14 mA/cm2 at 1.6 V. The OER activity does not declined after 10,000 potential cycles demonstrating excellent stability, which is superior to the benchmark of Ir for the OER. This work provides an effective solution to enhance catalytic activity and stability of oxides by engineering their morphology and nanostructures. The high performance bifunctional oxide catalyst is carbon free and can eventually overcome the stability issue for reversible fuel cell and metal-air battery applications. In addition, we have synthesized highly active transition metal doped Carbon Nano Tubes of very small thickness called Graphene Tubes which when integrated with metal oxides can lead to enhanced activity and durability for ORR and OER with current density as high as 25mAcm-2 at 1.6V vs RHE for OER and an onset potential of 1.0V vs RHE during ORR. Finally, we conclude by giving a brief description of the Hydrogen Economy and the role that ammonia decomposition can play in achieving the potential of hydrogen economy. We detail the synthesis procedures of some highly active transition metal nitride- alkali metal imide composites and study their activity for ammonia decomposition. The catalysts show conversion efficiencies as high as 95%.

Effect of chronic intake of liquid nutrition on stomach and duodenum morphology.

PubMed

Vrabcova, Michaela; Mikuska, Livia; Vazan, Rastislav; Miko, Michal; Varga, Ivan; Mravec, Boris

2016-05-01

Changes in the quantity and/or quality of food intake have been shown to be associated with morphological and functional alterations of the gastrointestinal system. To examine this, we investigated the effect of chronic liquid nutrition intake (Fresubin) on stomach and duodenum morphology in Wistar rats fed liquid nutrition during different developmental periods. We used four groups of rats: a) control group (CON) fed pelleted chow for 130days; b) liquid nutrition group (LN) fed liquid nutrition for 130days; c) liquid nutrition juvenile group (LNJ) fed liquid nutrition for 70days and then pelleted food for 60days; d) liquid nutrition adult group (LNA) fed pelleted chow for 70days and then liquid nutrition for 60days. We found that LN and LNA rats showed a significant reduction of empty stomach mass compared to CON animals, while stomach and duodenal longitudinal muscle layer thickness did not differ between groups. Villus height was increased only in LNA animals, while villus width was increased in both LN and LNA rats. Crypt depth was reduced in LNJ. However, liquid nutrition intake did not affect villus height/crypt depth ratio, nor number of goblet cells. We found that chronic intake of liquid nutrition affects some morphological parameters of the stomach and duodenum but these changes were not homogenous between experimental groups. Interestingly, transition from liquid nutrition to solid food reversed the alterations of stomach weight as well as villus width induced by intake of liquid nutrition in LNA rats. Our data indicate that morphological and functional changes in the gastrointestinal system induced by qualitative and quantitative changes in food intake are at least partially reversible. Therefore, specific diets may be used potentially as adjuvant treatment for modulating the progression of gastrointestinal diseases by affecting stomach and small intestine morphology. Copyright © 2016 Elsevier GmbH. All rights reserved.

Functional aspects of metatarsal head shape in humans, apes, and Old World monkeys.

PubMed

Fernández, Peter J; Almécija, Sergio; Patel, Biren A; Orr, Caley M; Tocheri, Matthew W; Jungers, William L

2015-09-01

Modern human metatarsal heads are typically described as "dorsally domed," mediolaterally wide, and dorsally flat. Despite the apparent functional importance of these features in forefoot stability during bipedalism, the distinctiveness of this morphology has not been quantitatively evaluated within a broad comparative framework. In order to use these features to reconstruct fossil hominin locomotor behaviors with any confidence, their connection to human bipedalism should be validated through a comparative analysis of other primates with different locomotor behaviors and foot postures, including species with biomechanical demands potentially similar to those of bipedalism (e.g., terrestrial digitigrady). This study explores shape variation in the distal metatarsus among humans and other extant catarrhines using three-dimensional geometric morphometrics (3 DGM). Shape differences among species in metatarsal head morphology are well captured by the first two principal components of Procrustes shape coordinates, and these two components summarize most of the variance related to "dorsal doming" and "dorsal expansion." Multivariate statistical tests reveal significant differences among clades in overall shape, and humans are reliably distinguishable from other species by aspects of shape related to a greater degree of dorsal doming. Within quadrupeds, terrestrial species also trend toward more domed metatarsal heads, but not to the extent seen in humans. Certain aspects of distal metatarsus shape are likely related to habitual dorsiflexion of the metatarsophalangeal joints, but the total morphological pattern seen in humans is distinct. These comparative results indicate that this geometric morphometric approach is useful to characterize the complexity of metatarsal head morphology and will help clarify its relationship with function in fossil primates, including early hominins. Published by Elsevier Ltd.

Dynamic behavior of Yarrowia lipolytica in response to pH perturbations: dependence of the stress response on the culture mode.

PubMed

Timoumi, Asma; Cléret, Mégane; Bideaux, Carine; Guillouet, Stéphane E; Allouche, Yohan; Molina-Jouve, Carole; Fillaudeau, Luc; Gorret, Nathalie

2017-01-01

Yarrowia lipolytica, a non-conventional yeast with a promising biotechnological potential, is able to undergo metabolic and morphological changes in response to environmental conditions. The effect of pH perturbations of different types (pulses, Heaviside) on the dynamic behavior of Y. lipolytica W29 strain was characterized under two modes of culture: batch and continuous. In batch cultures, different pH (4.5, 5.6 (optimal condition), and 7) were investigated in order to identify the pH inducing a stress response (metabolic and/or morphologic) in Y. lipolytica. Macroscopic behavior (kinetic parameters, yields, viability) of the yeast was slightly affected by pH. However, contrary to the culture at pH 5.6, a filamentous growth was induced in batch experiments at pH 4.5 and 7. Proportions of the filamentous subpopulation reached 84 and 93 % (v/v) under acidic and neutral conditions, respectively. Given the significant impact of neutral pH on morphology, pH perturbations from 5.6 to 7 were subsequently assayed in batch and continuous bioreactors. For both process modes, the growth dynamics remained fundamentally unaltered during exposure to stress. Nevertheless, morphological behavior of the yeast was dependent on the culture mode. Specifically, in batch bioreactors where cells proliferated at their maximum growth rate, mycelia were mainly formed. Whereas, in continuous cultures at controlled growth rates (from 0.03 to 0.20 h -1 ) even closed to the maximum growth rate of the stain (0.24 h -1 ), yeast-like forms predominated. This pointed out differences in the kinetic behavior of filamentous and yeast subpopulations, cell age distribution, and pH adaptive mechanisms between both modes of culture.

Inactivation of chemical and heat-resistant spores of Bacillus and Geobacillus by nitrogen cold atmospheric plasma evokes distinct changes in morphology and integrity of spores.

PubMed

van Bokhorst-van de Veen, Hermien; Xie, Houyu; Esveld, Erik; Abee, Tjakko; Mastwijk, Hennie; Nierop Groot, Masja

2015-02-01

Bacterial spores are resistant to severe conditions and form a challenge to eradicate from food or food packaging material. Cold atmospheric plasma (CAP) treatment is receiving more attention as potential sterilization method at relatively mild conditions but the exact mechanism of inactivation is still not fully understood. In this study, the biocidal effect by nitrogen CAP was determined for chemical (hypochlorite and hydrogen peroxide), physical (UV) and heat-resistant spores. The three different sporeformers used are Bacillus cereus a food-borne pathogen, and Bacillus atrophaeus and Geobacillus stearothermophilus that are used as biological indicators for validation of chemical sterilization and thermal processes, respectively. The different spores showed variation in their degree of inactivation by applied heat, hypochlorite, hydrogen peroxide, and UV treatments, whereas similar inactivation results were obtained with the different spores treated with nitrogen CAP. G. stearothermophilus spores displayed high resistance to heat, hypochlorite, hydrogen peroxide, while for UV treatment B. atrophaeus spores are most tolerant. Scanning electron microscopy analysis revealed distinct morphological changes for nitrogen CAP-treated B. cereus spores including etching effects and the appearance of rough spore surfaces, whereas morphology of spores treated with heat or disinfectants showed no such changes. Moreover, microscopy analysis revealed CAP-exposed B. cereus spores to turn phase grey conceivably because of water influx indicating damage of the spores, a phenomenon that was not observed for non-treated spores. In addition, data are supplied that exclude UV radiation as determinant of antimicrobial activity of nitrogen CAP. Overall, this study shows that nitrogen CAP treatment has a biocidal effect on selected Bacillus and Geobacillus spores associated with alterations in spore surface morphology and loss of spore integrity. Copyright © 2014 Elsevier Ltd. All rights reserved.

Control of dental-derived induced pluripotent stem cells through modified surfaces for dental application.

PubMed

Choi, Hyunmin; Park, Kyu-Hyung; Lee, Ah-Reum; Mun, Chin Hee; Shin, Yong Dae; Park, Yong-Beom; Park, Young-Bum

2017-07-01

The aim of this study is to investigate the behaviour of iPSc derived from dental stem cells in terms of initial adhesion, differentiation potential on differently surface-treated titanium disc. iPSc derived from human gingival fibroblasts (hGFs) were established using 4-reprogramming factors transduction with Sendai virus. The hGF-iPSc established in this study exhibited the morphology and growth properties similar to human embryonic stem (ES) cells and expressed pluripotency makers. Alkaline Phosphatase (AP) staining, Embryoid Body (EB) formation and in vitro differentiation and karyotyping further confirmed pluripotency of hGF-iPSc. Then, hGF-iPSc were cultured on machined- and Sandblasted and acid etched (SLA)-treated titanium discs with osteogenic induction medium and their morphological as well as quantitative changes according to different surface types were investigated using Alizrin Red S staining, Scanning electron microscopy (SEM), Flow cytometry and RT-PCR. Time-dependent and surface-dependent morphological changes as well as quantitative change in osteogenic differentiation of hGF-iPSc were identified and osteogenic gene expression of hGF-iPSc cultured on SLA-treated titanium disc found to be greater than machined titanium disc, suggesting the fate of hGF-iPSc may be determined by the characteristics of surface to which hGF-iPSc first adhere. iPSc derived from dental stem cell can be one of the most promising and practical cell sources for personalized regenerative dentistry and their morphological change as well as quantitative change in osteogenic differentiation according to different surface types may be further utilized for future clinical application incorporated with dental implant.

Differences in hydraulic architecture between mesic and xeric Pinus pinaster populations at the seedling stage.

PubMed

Corcuera, Leyre; Gil-Pelegrín, Eustaquio; Notivol, Eduardo

2012-12-01

We studied the intraspecific variability of maritime pine in a set of morphological and physiological traits: soil-to-leaf hydraulic conductance, intrinsic water-use efficiency (WUE, estimated by carbon isotope composition, δ(13)C), root morphology, xylem anatomy, growth and carbon allocation patterns. The data were collected from Pinus pinaster Aiton seedlings (25 half-sib families from five populations) grown in a greenhouse and subjected to water and water-stress treatments. The aims were to relate this variability to differences in water availability at the geographic location of the populations, and to study the potential trade-offs among traits. The drought-stressed seedlings demonstrated a decrease in hydraulic conductance and root surface area and increased WUE and root tip number. The relationships among the growth, morphological, anatomical and physiological traits changed with the scale of study: within the species, among/within populations. The populations showed a highly significant relationship between the percentage reduction in whole-plant hydraulic conductance and WUE. The differences among the populations in root morphology, whole-plant conductance, carbon allocation, plant growth and WUE were significant and consistent with dryness of the site of seed origin. The xeric populations exhibited lower growth and a conservative water use, as opposed to the fast-growing, less water-use-efficient populations from mesic habitats. The xeric and mesic populations, Tamrabta and San Cipriano, respectively, showed the most contrasting traits and were clustered in opposite directions along the main axis in the canonical discriminant analysis under both the control and drought treatments. The results suggest the possibility of selecting the Arenas population, which presents a combination of traits that confer increased growth and drought resistance.

Morphological divergence between three Arctic charr morphs - the significance of the deep-water environment.

PubMed

Skoglund, Sigrid; Siwertsson, Anna; Amundsen, Per-Arne; Knudsen, Rune

2015-08-01

Morphological divergence was evident among three sympatric morphs of Arctic charr (Salvelinus alpinus (L.)) that are ecologically diverged along the shallow-, deep-water resource axis in a subarctic postglacial lake (Norway). The two deep-water (profundal) spawning morphs, a benthivore (PB-morph) and a piscivore (PP-morph), have evolved under identical abiotic conditions with constant low light and temperature levels in their deep-water habitat, and were morphologically most similar. However, they differed in important head traits (e.g., eye and mouth size) related to their different diet specializations. The small-sized PB-morph had a paedomorphic appearance with a blunt head shape, large eyes, and a deep body shape adapted to their profundal lifestyle feeding on submerged benthos from soft, deep-water sediments. The PP-morph had a robust head, large mouth with numerous teeth, and an elongated body shape strongly related to their piscivorous behavior. The littoral spawning omnivore morph (LO-morph) predominantly utilizes the shallow benthic-pelagic habitat and food resources. Compared to the deep-water morphs, the LO-morph had smaller head relative to body size. The LO-morph exhibited traits typical for both shallow-water benthic feeding (e.g., large body depths and small eyes) and planktivorous feeding in the pelagic habitat (e.g., streamlined body shape and small mouth). The development of morphological differences within the same deep-water habitat for the PB- and PP-morphs highlights the potential of biotic factors and ecological interactions to promote further divergence in the evolution of polymorphism in a tentative incipient speciation process. The diversity of deep-water charr in this study represents a novelty in the Arctic charr polymorphism as a truly deep-water piscivore morph has to our knowledge not been described elsewhere.

Sorting Out Effects of Active Stream Restoration: Channel Morphology, Channel Change Processes and Potential Controls

NASA Astrophysics Data System (ADS)

McDowell, P. F.

2017-12-01

In many active restoration projects, instream structures or modifications are designed to produce specific change in channel form, such as reduced W:D or increased pool depth, yet there is little monitoring to evaluate effectiveness. Active restoration often takes place within a context of other land management changes that can have an effect on channel form. Thus, the effects of active restoration are difficult to separate from the effects of other management actions. We measured morphologic response to restoration designs on sections of the Middle Fork John Day River, a gravel-cobble bed river under a cattle grazing regime in the Blue Mountain of Oregon. Since 2000, restoration actions have included elimination of cattle grazing in the riparian zone (passive restoration), riparian planting of woody vegetation, instream log structures for fish habitat and pool maintenance, and elimination of a major flow diversion. We listed the hypothetical effects of each of these management changes, showing overlap among effects of active and passive restoration. Repeat cross-section and longitudinal profile surveys over eight years, and repeat aerial imagery, documented changes in channel width, depth and bed morphology, and processes of change (bank erosion or aggradation, point bar erosion or aggradation, bed incision or aggradation), in two restored reaches and two adjacent control (unrestored) reaches. Morphologic changes were modest. Bankfull cross-section area, width, and W:D all decreased slightly in both restored reaches. Control reaches were unchanged or increased slightly. Processes of change were markedly different among the four reaches, with different reaches dominated by different processes. One restored reach was dominated by slight bed aggradation, increased pool depth and deep pools/km, while the other restored reach was dominated by bank erosion, bar aggradation and slight bed incision, along with increased deep pools/km. The longitudinal profile showed significant re-arrangement of bed morphology. The spatial context of processes and controls allows some separation of the effectiveness of different management actions. Active restoration directly increased pool depth, but passive restoration apparently had more impact on aggradation/degradation and width.

DNA as a powerful tool for morphology control, spatial positioning, and dynamic assembly of nanoparticles.

PubMed

Tan, Li Huey; Xing, Hang; Lu, Yi

2014-06-17

CONSPECTUS: Several properties of nanomaterials, such as morphologies (e.g., shapes and surface structures) and distance dependent properties (e.g., plasmonic and quantum confinement effects), make nanomaterials uniquely qualified as potential choices for future applications from catalysis to biomedicine. To realize the full potential of these nanomaterials, it is important to demonstrate fine control of the morphology of individual nanoparticles, as well as precise spatial control of the position, orientation, and distances between multiple nanoparticles. In addition, dynamic control of nanomaterial assembly in response to multiple stimuli, with minimal or no error, and the reversibility of the assemblies are also required. In this Account, we summarize recent progress of using DNA as a powerful programmable tool to realize the above goals. First, inspired by the discovery of genetic codes in biology, we have discovered DNA sequence combinations to control different morphologies of nanoparticles during their growth process and have shown that these effects are synergistic or competitive, depending on the sequence combination. The DNA, which guides the growth of the nanomaterial, is stable and retains its biorecognition ability. Second, by taking advantage of different reactivities of phosphorothioate and phosphodiester backbone, we have placed phosphorothioate at selective positions on different DNA nanostructures including DNA tetrahedrons. Bifunctional linkers have been used to conjugate phosphorothioate on one end and bind nanoparticles or proteins on the other end. In doing so, precise control of distances between two or more nanoparticles or proteins with nanometer resolution can be achieved. Furthermore, by developing facile methods to functionalize two hemispheres of Janus nanoparticles with two different DNA sequences regioselectively, we have demonstrated directional control of nanomaterial assembly, where DNA strands with specific hybridization serve as orthogonal linkers. Third, by using functional DNA that includes DNAzyme, aptamer, and aptazyme, dynamic control of assemblies of gold nanoparticles, quantum dots, carbon nanotubes, and iron oxide nanoparticles in response to one or more stimuli cooperatively have been achieved, resulting in colorimetric, fluorescent, electrochemical, and magnetic resonance signals for a wide range of targets, such as metal ions, small molecules, proteins, and intact cells. Fourth, by mimicking biology, we have employed DNAzymes as proofreading units to remove errors in nanoparticle assembly and further used DNAzyme cascade reactions to modify or repair DNA sequences involved in the assembly. Finally, by taking advantage of different affinities of biotin and desthiobiotin toward streptavidin, we have demonstrated reversible assembly of proteins on DNA origami.

Role of larval host plants in the climate-driven range expansion of the butterfly Polygonia c-album.

PubMed

Braschler, Brigitte; Hill, Jane K

2007-05-01

1. Some species have expanded their ranges during recent climate warming and the availability of breeding habitat and species' dispersal ability are two important factors determining expansions. The exploitation of a wide range of larval host plants should increase an herbivorous insect species' ability to track climate by increasing habitat availability. Therefore we investigated whether the performance of a species on different host plants changed towards its range boundary, and under warmer temperatures. 2. We studied the polyphagous butterfly Polygonia c-album, which is currently expanding its range in Britain and apparently has altered its host plant preference from Humulus lupulus to include other hosts (particularly Ulmus glabra and Urtica dioica). We investigated insect performance (development time, larval growth rate, adult size, survival) and adult flight morphology on these host plants under four rearing temperatures (18-28.5 degrees C) in populations from core and range margin sites. 3. In general, differences between core and margin populations were small compared with effects of rearing temperature and host plant. In terms of insect performance, host plants were generally ranked U. glabra > or = U. dioica > H. lupulus at all temperatures. Adult P. c-album can either enter diapause or develop directly and higher temperatures resulted in more directly developing adults, but lower survival rates (particularly on the original host H. lupulus) and smaller adult size. 4. Adult flight morphology of wild-caught individuals from range margin populations appeared to be related to increased dispersal potential relative to core populations. However, there was no difference in laboratory reared individuals, and conflicting results were obtained for different measures of flight morphology in relation to larval host plant and temperature effects, making conclusions about dispersal potential difficult. 5. Current range expansion of P. c-album is associated with the exploitation of more widespread host plants on which performance is improved. This study demonstrates how polyphagy may enhance the ability of species to track climate change. Our findings suggest that observed differences in climate-driven range shifts of generalist vs. specialist species may increase in the future and are likely to lead to greatly altered community composition.

Reconstructing Holocene Summer Sea-Ice Conditions in the Central and Western Arctic Ocean: Morphological Variations and Stable Isotope Composition of Neogloboquadrina pachyderma

NASA Astrophysics Data System (ADS)

Asahi, H.; Nam, S. I.; Stein, R. H.; Mackensen, A.; Son, Y. J.

2017-12-01

The usability of planktic foraminiferal census data in Arctic paleoceanography is limited by the predominance of Neogloboquadrina pachyderma (sinistral). Though a potential usability of their morphological variation has been suggested by recent studies, its application is restricted to the central part of the Arctic Ocean. Here we present their regional distribution, using 80 surface sediment samples from the central and the western Arctic Ocean. Among seven morphological variations encountered, distinct presence of "large-sized" N. pachyderma morphotypes at the summer sea-ice edge in the western Arctic demonstrates its strong potential as sea-ice distribution indicator. Based on their regional patterns, we further developed planktic foraminifer (PF)-based transfer functions (TFs) to reconstruct summer surface-water temperature, salinity and sea-ice concentration in the western and central Arctic. The comparison of sea-ice reconstructions by PF-based TF to other pre-existed approaches showed their recognizable advantages/disadvantages: the PF-based approach in the nearby/within heavily ice-covered region, the dinocyst-based approach in the extensively seasonal ice retreat region, and the IP25-based approach with overall reflection over a wide range of sea-ice coverage, which is likely attributed to their (a) taphonomical information-loss, (b) different seasonal production patterns or combination of both. The application of these TFs on a sediment core from Northwind Ridge suggests general warming, freshening, and sea-ice reduction after 6.0 ka. This generally agrees with PF stable isotope records and sea-ice reconstructions from dinocyst-based TF at proximal locations, indicating that the sea-ice behavior at the Northwind Ridge is notably different from the IP25-based sea-ice reconstructions reported from elsewhere in the Arctic Ocean. Lack of regional coverage of PF-based reconstructions hampers further discussion whether the observed inconsistency is simply caused by different regional coverage of data and/or their different sensitivity yet. Thus, additional PF-census data with their isotope signatures from other cores from different ice regimes in the Arctic Ocean (e.g., Lomonosov Ridge and Mendeelev Ridge) will provide further discussion for such inconsisntency.

Can optical recordings of membrane potential be used to screen for drug-induced action potential prolongation in single cardiac myocytes?

PubMed

Hardy, M E L; Lawrence, C L; Standen, N B; Rodrigo, G C

2006-01-01

Potential-sensitive dyes have primarily been used to optically record action potentials (APs) in whole heart tissue. Using these dyes to record drug-induced changes in AP morphology of isolated cardiac myocytes could provide an opportunity to develop medium throughout assays for the pharmaceutical industry. Ideally, this requires that the dye has a consistent and rapid response to membrane potential, is insensitive to movement, and does not itself affect AP morphology. We recorded the AP from isolated adult guinea-pig ventricular myocytes optically using di-8-ANEPPS in a single-excitation dual-emission ratiometric system, either separately in electrically field stimulated myocytes, or simultaneously with an electrical AP recorded with a patch electrode in the whole-cell bridge mode. The ratio of di-8-ANEPPS fluorescence signal was calibrated against membrane potential using a switch-clamp to voltage clamp the myocyte. Our data show that the ratio of the optical signals emitted at 560/620 nm is linearly related to voltage over the voltage range of an AP, producing a change in ratio of 7.5% per 100 mV, is unaffected by cell movement and is identical to the AP recorded simultaneously with a patch electrode. However, the APD90 recorded optically in myocytes loaded with di-8-ANEPPS was significantly longer than in unloaded myocytes recorded with a patch electrode (355.6+/-13.5 vs. 296.2+/-16.2 ms; p<0.01). Despite this effect, the apparent IC50 for cisapride, which prolongs the AP by blocking IKr, was not significantly different whether determined optically or with a patch electrode (91+/-46 vs. 81+/-20 nM). These data show that the optical AP recorded ratiometrically using di-8-ANEPPS from a single ventricular myocyte accurately follows the action potential morphology. This technique can be used to estimate the AP prolonging effects of a compound, although di-8-ANEPPS itself prolongs APD90. Optical dyes require less technical skills and are less invasive than conventional electrophysiological techniques and, when coupled to ventricular myocytes, decreases animal usage and facilitates higher throughput assays.

Action of vanillin (Vanilla planifolia) on the morphology of tibialis anterior and soleus muscles after nerve injury

PubMed Central

Peretti, Ana Luiza; Antunes, Juliana Sobral; Lovison, Keli; Kunz, Regina Inês; Castor, Lidyane Regina Gomes; Brancalhão, Rose Meire Costa; Bertolini, Gladson Ricardo Flor; Ribeiro, Lucinéia de Fátima Chasko

2017-01-01

ABSTRACT Objective To evaluate the action of vanillin (Vanilla planifolia) on the morphology of tibialis anterior and soleus muscles after peripheral nerve injury. Methods Wistar rats were divided into four groups, with seven animals each: Control Group, Vanillin Group, Injury Group, and Injury + Vanillin Group. The Injury Group and the Injury + Vanillin Group animals were submitted to nerve injury by compression of the sciatic nerve; the Vanillin Group and Injury + Vanillin Group, were treated daily with oral doses of vanillin (150mg/kg) from the 3rd to the 21st day after induction of nerve injury. At the end of the experiment, the tibialis anterior and soleus muscles were dissected and processed for light microscopy and submitted to morphological analysis. Results The nerve compression promoted morphological changes, typical of denervation, and the treatment with vanillin was responsible for different responses in the studied muscles. For the tibialis anterior, there was an increase in the number of satellite cells, central nuclei and fiber atrophy, as well as fascicular disorganization. In the soleus, only increased vascularization was observed, with no exacerbation of the morphological alterations in the fibers. Conclusion The treatment with vanillin promoted increase in intramuscular vascularization for the muscles studied, with pro-inflammatory potential for tibialis anterior, but not for soleus muscle. PMID:28767917

Regulation the morphology of cationized gold nanoparticles for effective gene delivery.

PubMed

Zhang, Peng; Li, Bangbang; Du, Jianwei; Wang, Youxiang

2017-09-01

Recent research indicated that the morphology of nanoparticles could result in distinct biological behaviors, thus played an important role in designing efficient gene delivery systems. Among them, gold nanoparticles (AuNPs) with various shapes were widely studied due to the good biocompatibility and easy modification ability. Our recent research indicated that polyethyleneimine-g-bovine serum albumin (BSA-PEI) as non-viral gene vector showed good colloid stability and high transfection efficiency. In this work, BSA-PEI was utilized to modify gold nanospheres (AuNSs) and gold nanorods (AuNRs) to investigate the influence of the morphology on gene delivery. Both AuNS@BSA-PEI and AuNR@BSA-PEI nanoparticles condensed DNA effectively at N/P ratio above 5 and maintained spherical or rod-like morphology respectively. Due to the higher surface charge density at the tips, the rod-like gene complexes were prone to use the tips to contact with cell membrane, which facilitated to be uptaked by HepG2 cells. The endocytosis inhibition experiments showed some differences in the endocytic pathway. Gene transfection experiment showed that the rod-like complexes had almost 100-fold higher of transfection level than that of spherical complexes at the N/P ratio of 20. This work provided a potential strategy for further design of gene vectors with improved transfection results by adjusting the morphology of gene vectors. Copyright © 2017. Published by Elsevier B.V.

Analysis of Europan Cycloid Morphology and Implications for Formation Mechanisms

NASA Technical Reports Server (NTRS)

Marshall, S. T.; Kattenhorn, S. A.

2004-01-01

Europa's highly fractured crust has been shown to contain features with a range of differing morphologies. Most lineaments on Europa are believed to have initiated as cracks, although the type of cracking (e.g. tensile vs. shear) remains unclear and may vary for different morphologies. Arcuate lineaments, called cycloids or flexi, have been observed in nearly all imaged regions of Europa and have been modeled as tensile fractures that were initiated in response to diurnal variations in tides. Despite this hypothesis about the formation mechanism, there have been no detailed analyses of the variable morphologies of cycloids. We have examined Galileo images of numerous locations on Europa to develop a catalog of the different morphologies of cycloids. This study focuses on variations in morphology along individual cycloid segments and differences in cusp styles between segments, while illustrating how morphologic evidence can help unravel formation mechanisms. In so doing, we present evidence for cycloid cusps forming due to secondary fracturing during strike-slip sliding on pre-existing cycloid segments.

NGC1300 dynamics - II. The response models

NASA Astrophysics Data System (ADS)

Kalapotharakos, C.; Patsis, P. A.; Grosbøl, P.

2010-10-01

We study the stellar response in a spectrum of potentials describing the barred spiral galaxy NGC1300. These potentials have been presented in a previous paper and correspond to three different assumptions as regards the geometry of the galaxy. For each potential we consider a wide range of Ωp pattern speed values. Our goal is to discover the geometries and the Ωp supporting specific morphological features of NGC1300. For this purpose we use the method of response models. In order to compare the images of NGC1300 with the density maps of our models, we define a new index which is a generalization of the Hausdorff distance. This index helps us to find out quantitatively which cases reproduce specific features of NGC1300 in an objective way. Furthermore, we construct alternative models following a Schwarzschild-type technique. By this method we vary the weights of the various energy levels, and thus the orbital contribution of each energy, in order to minimize the differences between the response density and that deduced from the surface density of the galaxy, under certain assumptions. We find that the models corresponding to Ωp ~ 16 and 22 kms-1kpc-1 are able to reproduce efficiently certain morphological features of NGC1300, with each one having its advantages and drawbacks. Based on observations collected at the European Southern Observatory, Chile: programme ESO 69.A-0021. E-mail: ckalapot@phys.uoa.gr (CK); patsis@academyofathens.gr (PAP); pgrosbol@eso.org (PG)

Rapid prototyping of biomimetic vascular phantoms for hyperspectral reflectance imaging

PubMed Central

Ghassemi, Pejhman; Wang, Jianting; Melchiorri, Anthony J.; Ramella-Roman, Jessica C.; Mathews, Scott A.; Coburn, James C.; Sorg, Brian S.; Chen, Yu; Joshua Pfefer, T.

2015-01-01

Abstract. The emerging technique of rapid prototyping with three-dimensional (3-D) printers provides a simple yet revolutionary method for fabricating objects with arbitrary geometry. The use of 3-D printing for generating morphologically biomimetic tissue phantoms based on medical images represents a potentially major advance over existing phantom approaches. Toward the goal of image-defined phantoms, we converted a segmented fundus image of the human retina into a matrix format and edited it to achieve a geometry suitable for printing. Phantoms with vessel-simulating channels were then printed using a photoreactive resin providing biologically relevant turbidity, as determined by spectrophotometry. The morphology of printed vessels was validated by x-ray microcomputed tomography. Channels were filled with hemoglobin (Hb) solutions undergoing desaturation, and phantoms were imaged with a near-infrared hyperspectral reflectance imaging system. Additionally, a phantom was printed incorporating two disjoint vascular networks at different depths, each filled with Hb solutions at different saturation levels. Light propagation effects noted during these measurements—including the influence of vessel density and depth on Hb concentration and saturation estimates, and the effect of wavelength on vessel visualization depth—were evaluated. Overall, our findings indicated that 3-D-printed biomimetic phantoms hold significant potential as realistic and practical tools for elucidating light–tissue interactions and characterizing biophotonic system performance. PMID:26662064

Rapid prototyping of biomimetic vascular phantoms for hyperspectral reflectance imaging.

PubMed

Ghassemi, Pejhman; Wang, Jianting; Melchiorri, Anthony J; Ramella-Roman, Jessica C; Mathews, Scott A; Coburn, James C; Sorg, Brian S; Chen, Yu; Pfefer, T Joshua

2015-01-01

The emerging technique of rapid prototyping with three-dimensional (3-D) printers provides a simple yet revolutionary method for fabricating objects with arbitrary geometry. The use of 3-D printing for generating morphologically biomimetic tissue phantoms based on medical images represents a potentially major advance over existing phantom approaches. Toward the goal of image-defined phantoms, we converted a segmented fundus image of the human retina into a matrix format and edited it to achieve a geometry suitable for printing. Phantoms with vessel-simulating channels were then printed using a photoreactive resin providing biologically relevant turbidity, as determined by spectrophotometry. The morphology of printed vessels was validated by x-ray microcomputed tomography. Channels were filled with hemoglobin (Hb) solutions undergoing desaturation, and phantoms were imaged with a near-infrared hyperspectral reflectance imaging system. Additionally, a phantom was printed incorporating two disjoint vascular networks at different depths, each filled with Hb solutions at different saturation levels. Light propagation effects noted during these measurements—including the influence of vessel density and depth on Hb concentration and saturation estimates, and the effect of wavelength on vessel visualization depth—were evaluated. Overall, our findings indicated that 3-D-printed biomimetic phantoms hold significant potential as realistic and practical tools for elucidating light–tissue interactions and characterizing biophotonic system performance.

Shape control of II-VI semiconductor nanomaterials.

PubMed

Kumar, Sandeep; Nann, Thomas

2006-03-01

Anisotropic II-VI semiconductor nanocrystals and nanoparticles have become important building blocks for (potential) nanotechnological applications. Even though a wide variety of differently shaped nanoparticles of this class can be prepared, the underlying mechanisms are mostly not fully understood. This Review article provides a brief overview of the currently studied shape-evolution mechanisms and the most prominent synthesis methods for such particles, with an aim to provide a fundamental understanding on how different morphologies evolve, and to function as a tool to aid in the preparation of specific nanocrystals.

Plastic efficiency of different implants used for repair of soft and bone tissue defects.

PubMed

Iriyanov, Yu M; Chernov, V F; Radchenko, S A; Chernov, A V

2013-08-01

The results of clinical and experimental morphological studies of regenerates forming after replacement of large defects of the abdominal wall and tibia with implants from different materials (polytetrafluoroethylene, reperene, prolene, titanium, and titanium nickelide) are analyzed. Study of the regenerate histology and fibroarchitectonics has shown good prospects of mesh constructions from titanium nickelide for effective surgical repair of these defects. The use of this implant seems to be theoretically well-based and promising, particularly under conditions of suppurative infection and low individual reparative regenerative potential.

Electrodeposition of Rhodium Nanowires Arrays and Their Morphology-Dependent Hydrogen Evolution Activity

PubMed Central

Zhang, Liqiu; Liu, Lichun; Wang, Hongdan; Shen, Hongxia; Cheng, Qiong; Yan, Chao; Park, Sungho

2017-01-01

This work reports on the electrodeposition of rhodium (Rh) nanowires with a controlled surface morphology synthesized using an anodic aluminum oxide (AAO) template. Vertically aligned Rh nanowires with a smooth and coarse morphology were successfully deposited by adjusting the electrode potential and the concentration of precursor ions and by involving a complexing reagent in the electrolyte solution. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses were used to follow the morphological evolution of Rh nanowires. As a heterogeneous electrocatalyst for hydrogen evolution reactions (HER), the coarse Rh nanowire array exhibited an enhanced catalytic performance respect to smooth ones due to the larger surface area to mass ratio and the higher density of catalytically active defects, as evidenced by voltammetric measurements and TEM. Results suggest that the morphology of metallic nanomaterials could be readily engineered by electrodeposition. The controlled electrodeposition offers great potential for the development of an effective synthesis tool for heterogeneous catalysts with a superior performance for wide applications. PMID:28467375

Retinoschisislike alterations in the mouse eye caused by gene targeting of the Norrie disease gene.

PubMed

Ruether, K; van de Pol, D; Jaissle, G; Berger, W; Tornow, R P; Zrenner, E

1997-03-01

To investigate the retinal function and morphology of mice carrying a replacement mutation in exon 2 of the Norrie disease gene. Recently, Norrie disease mutant mice have been generated using gene targeting technology. The mutation removes the 56 N-terminal amino acids of the Norrie gene product. Ganzfeld electroretinograms (ERGs) were obtained in five animals hemizygous or homozygous for the mutant gene and in three female animals heterozygous for the mutant gene. As controls, three males carrying the wild-type gene were examined. Electroretinogram testing included rod a- and b-wave V-log I functions, oscillatory potentials, and cone responses. The fundus morphology has been visualized by scanning laser ophthalmoscopy. Rod and cone ERG responses and fundus morphology were not significantly different among female heterozygotes and wild-type mice. In contrast, the hemizygous mice displayed a severe loss of ERG b-wave, leading to a negatively shaped scotopic ERG and a marked reduction of oscillatory potentials. The a-wave was normal at low intensities, and only with brighter flashes was there a moderate amplitude loss. Cone amplitudes were barely recordable in the gene-targeted males. Ophthalmoscopy revealed snowflakelike vitreal changes, retinoschisis, and pigment epithelium irregularities in hemizygotes and homozygotes, but no changes in female heterozygotes. The negatively shaped scotopic ERG in male mice with a Norrie disease gene mutation probably was caused by retinoschisis. Pigment epithelial changes and degenerations of the outer retina are relatively mild. These findings may be a clue to the embryonal retinoschisislike pathogenesis of Norrie disease in humans or it may indicate a different expression of the Norrie disease gene defect in mice compared to that in humans.

Stability, Intracellular Delivery, and Release of siRNA from Chitosan Nanoparticles Using Different Cross-Linkers

PubMed Central

Abdul Ghafoor Raja, Maria; Katas, Haliza; Jing Wen, Thum

2015-01-01

Chitosan (CS) nanoparticles have been extensively studied for siRNA delivery; however, their stability and efficacy are highly dependent on the types of cross-linker used. To address this issue, three common cross-linkers; tripolyphosphate (TPP), dextran sulphate (DS) and poly-D-glutamic acid (PGA) were used to prepare siRNA loaded CS-TPP/DS/PGA nanoparticles by ionic gelation method. The resulting nanoparticles were compared with regard to their physicochemical properties including particle size, zeta potential, morphology, binding and encapsulation efficiencies. Among all the formulations prepared with different cross linkers, CS-TPP-siRNA had the smallest particle size (ranged from 127 ± 9.7 to 455 ± 12.9 nm) with zeta potential ranged from +25.1 ± 1.5 to +39.4 ± 0.5 mV, and high entrapment (>95%) and binding efficiencies. Similarly, CS-TPP nanoparticles showed better siRNA protection during storage at 4˚C and as determined by serum protection assay. TEM micrographs revealed the assorted morphology of CS-TPP-siRNA nanoparticles in contrast to irregular morphology displayed by CS-DS-siRNA and CS-PGA-siRNA nanoparticles. All siRNA loaded CS-TPP/DS/PGA nanoparticles showed initial burst release followed by sustained release of siRNA. Moreover, all the formulations showed low and concentration-dependent cytotoxicity with human colorectal cancer cells (DLD-1), in vitro. The cellular uptake studies with CS-TPP-siRNA nanoparticles showed successful delivery of siRNA within cytoplasm of DLD-1 cells. The results demonstrate that ionically cross-linked CS-TPP nanoparticles are biocompatible non-viral gene delivery system and generate a solid ground for further optimization studies, for example with regard to steric stabilization and targeting. PMID:26068222

Genetic diversity in a morphologically conservative invasive taxon: Multiple introductions of swamp eels to the southeastern United States

USGS Publications Warehouse

Collins, T.M.; Trexler, J.C.; Nico, L.G.; Rawlings, T.A.

2002-01-01

Genetic analysis of introduced populations, especially in morphologically conservative taxa, can clarify introduction histories, identify management units and source populations, provide a more realistic estimate of the frequency of successful invasion, and suggest strategies for preventing further introductions. In the last 7 years, populations of swamp eels, referred to the Asian genus Monopterus (Family Synbranchidae) on the basis of external morphology, have been discovered in aquatic habitats near Atlanta, Georgia; Tampa, Florida; North Miami, Florida; and most recently in close proximity to Everglades National Park in Homestead, Florida. Swamp eels are large predators capable of dispersal over land and have the potential to disrupt already threatened ecosystems. We analyzed mitochondrial DNA sequences from four known populations in the continental United States and samples from Malaysia, Indonesia, Vietnam, and two locations in China to determine introduction histories, source populations, genetic diversity, and relationships among populations. Our results indicate that there have been at least three independent introductions of genetically distinct forms. Introduced populations in close proximity (separated by <40 km) are genetically distinct. The level of sequence difference among introduced populations reaches levels seen among sister families of teleost fishes for the same region of the mitochondrial genome. These genetically distinct introduced populations in all likelihood represent at least two and possibly three species. Regardless of species status, these genetically distinct lineages may be expected to vary in ecological or life-history traits, representing different potential threats to the ecosystems where they have been introduced. Given the success of swamp eels in invading many habitats around the world, further study of these eels is warranted to elucidate the characteristics of successful invaders and invasions.

Extracellular matrix protein in calcified endoskeleton: a potential additive for crystal growth and design

NASA Astrophysics Data System (ADS)

Azizur Rahman, M.; Fujimura, Hiroyuki; Shinjo, Ryuichi; Oomori, Tamotsu

2011-06-01

In this study, we demonstrate a key function of extracellular matrix proteins (ECMPs) on seed crystals, which are isolated from calcified endoskeletons of soft coral and contain only CaCO 3 without any living cells. This is the first report that an ECMP protein extracted from a marine organism could potentially influence in modifying the surface of a substrate for designing materials via crystallization. We previously studied with the ECMPs from a different type of soft coral ( Sinularia polydactyla) without introducing any seed crystals in the process , which showed different results. Thus, crystallization on the seed in the presence of ECMPs of present species is an important first step toward linking function to individual proteins from soft coral. For understanding this interesting phenomenon, in vitro crystallization was initiated in a supersaturated solution on seed particles of calcite (1 0 4) with and without ECMPs. No change in the crystal growth shape occurred without ECMPs present during the crystallization process. However, with ECMPs, the morphology and phase of the crystals in the crystallization process changed dramatically. Upon completion of crystallization with ECMPs, an attractive crystal morphology was found. Scanning electron microscopy (SEM) was utilized to observe the crystal morphologies on the seeds surface. The mineral phases of crystals nucleated by ECMPs on the seeds surface were examined by Raman spectroscopy. Although 50 mM Mg 2+ is influential in making aragonite in the crystallization process, the ECMPs significantly made calcite crystals even when 50 mM Mg 2+ was present in the process. Crystallization with the ECMP additive seems to be a technically attractive strategy to generate assembled micro crystals that could be used in crystals growth and design in the Pharmaceutical and biotechnology industries.

Effect of Students' Term and Educational Institution on the Arising of Indonesian Morphology-Syntactical Interference in ELLT

ERIC Educational Resources Information Center

Nurhayati, Dwi Astuti Wahyu; Djatmika; Santosa, Riyadi; Wiratno, Tri

2017-01-01

This research examines the two factors which effect on the raising of Indonesian morphology-syntactical interference. It aimed at delineating the potential effect of these two factors on the arising of Indonesian morphology-syntactical interference of undergraduate students majoring in English department of State Islamic Institute of Tulungagung…

Pre-Quaternary divergence and subsequent radiation explain longitudinal patterns of genetic and morphological variation in the striped skink, Heremites vittatus.

PubMed

Baier, Felix; Schmitz, Andreas; Sauer-Gürth, Hedwig; Wink, Michael

2017-06-09

Many animal and plant species in the Middle East and northern Africa have a predominantly longitudinal distribution, extending from Iran and Turkey along the eastern Mediterranean coast into northern Africa. These species are potentially characterized by longitudinal patterns of biological diversity, but little is known about the underlying biogeographic mechanisms and evolutionary timescales. We examined these questions in the striped skink, Heremites vittatus, one such species with a roughly longitudinal distribution across the Middle East and northern Africa, by analyzing range-wide patterns of mitochondrial DNA (mtDNA) sequence and multi-trait morphological variation. The striped skink exhibits a basic longitudinal organization of mtDNA diversity, with three major mitochondrial lineages inhabiting northern Africa, the eastern Mediterranean coast, and Turkey/Iran. Remarkably, these lineages are of pre-Quaternary origin, and are characterized by p-distances of 9-10%. In addition, within each of these lineages a more recent Quaternary genetic diversification was observed, as evidenced by deep subclades and high haplotype diversity especially in the Turkish/Iranian and eastern Mediterranean lineages. Consistent with the genetic variation, our morphological analysis revealed that the majority of morphological traits show significant mean differences between specimens from northern Africa, the eastern Mediterranean coast, and Turkey/Iran, suggesting lineage-specific trait evolution. In addition, a subset of traits exhibits clinal variation along the eastern Mediterranean coast, potentially indicating selection gradients at the geographic transition from northern Africa to Anatolia. The existence of allopatric, morphologically and genetically divergent lineages suggests that Heremites vittatus might represent a complex with several taxa. Our work demonstrates that early divergence events in the Pliocene, likely driven by both climatic and geological factors, established the longitudinal patterns and distribution of Heremites vittatus. Subsequent radiation during the Pleistocene generated the genetic and morphological diversity observed today. Our study provides further evidence that longitudinal diversity patterns and species distributions in the Middle East and northern Africa were shaped by complex evolutionary processes, involving the region's intricate geological history, climatic oscillations, and the presence of the Sahara.

Separability of Lexical and Morphological Knowledge: Evidence from Language Minority Children

PubMed Central

Shahar-Yames, Daphna; Eviatar, Zohar; Prior, Anat

2018-01-01

Lexical and morphological knowledge of school-aged children are correlated with each other, and are often difficult to distinguish. One reason for this might be that many tasks currently used to assess morphological knowledge require children to inflect or derive real words in the language, thus recruiting their vocabulary knowledge. The current study investigated the possible separability of lexical and morphological knowledge using two complementary approaches. First, we examined the correlations between vocabulary and four morphological tasks tapping different aspects of morphological processing and awareness, and using either real-word or pseudo-word stimuli. Thus, we tested the hypothesis that different morphological tasks recruit lexical knowledge to various degrees. Second, we compared the Hebrew vocabulary and morphological knowledge of 5th grade language minority speaking children to that of their native speaking peers. This comparison allows us to ask whether reduced exposure to the societal language might differentially influence vocabulary and morphological knowledge. The results demonstrate that indeed different morphological tasks rely on lexical knowledge to varying degrees. In addition, language minority students had significantly lower performance in vocabulary and in morphological tasks that recruited vocabulary knowledge to a greater extent. In contrast, both groups performed similarly in abstract morphological tasks with a lower vocabulary load. These results demonstrate that lexical and morphological knowledge may rely on partially separable learning mechanisms, and highlight the importance of distinguishing between these two linguistic components. PMID:29515486

To 3D or Not to 3D, That Is the Question: Do 3D Surface Analyses Improve the Ecomorphological Power of the Distal Femur in Placental Mammals?

PubMed Central

Gould, Francois D. H.

2014-01-01

Improvements in three-dimensional imaging technologies have renewed interest in the study of functional and ecological morphology. Quantitative approaches to shape analysis are used increasingly to study form-function relationships. These methods are computationally intensive, technically demanding, and time-consuming, which may limit sampling potential. There have been few side-by-side comparisons of the effectiveness of such approaches relative to more traditional analyses using linear measurements and ratios. Morphological variation in the distal femur of mammals has been shown to reflect differences in locomotor modes across clades. Thus I tested whether a geometric morphometric analysis of surface shape was superior to a multivariate analysis of ratios for describing ecomorphological patterns in distal femoral variation. A sample of 164 mammalian specimens from 44 genera was assembled. Each genus was assigned to one of six locomotor categories. The same hypotheses were tested using two methods. Six linear measurements of the distal femur were taken with calipers, from which four ratios were calculated. A 3D model was generated with a laser scanner, and analyzed using three dimensional geometric morphometrics. Locomotor category significantly predicted variation in distal femoral morphology in both analyses. Effect size was larger in the geometric morphometric analysis than in the analysis of ratios. Ordination reveals a similar pattern with arboreal and cursorial taxa as extremes on a continuum of morphologies in both analyses. Discriminant functions calculated from the geometric morphometric analysis were more accurate than those calculated from ratios. Both analysis of ratios and geometric morphometric surface analysis reveal similar, biologically meaningful relationships between distal femoral shape and locomotor mode. The functional signal from the morphology is slightly higher in the geometric morphometric analysis. The practical costs of conducting these sorts of analyses should be weighed against potentially slight increases in power when designing protocols for ecomorphological studies. PMID:24633081

Does Structural Complexity Determine the Morphology of Assemblages? An Experimental Test on Three Continents

PubMed Central

Gibb, Heloise; Parr, Catherine L.

2013-01-01

Understanding how species will respond to global change depends on our ability to distinguish generalities from idiosyncrasies. For diverse, but poorly known taxa, such as insects, species traits may provide a short-cut to predicting species turnover. We tested whether ant traits respond consistently to habitat complexity across geographically independent ant assemblages, using an experimental approach and baits. We repeated our study in six paired simple and complex habitats on three continents with distinct ant faunas. We also compared traits amongst ants with different foraging strategies. We hypothesised that ants would be larger, broader, have longer legs and more dorsally positioned eyes in simpler habitats. In agreement with predictions, ants had longer femurs and dorsally positioned eyes in simple habitats. This pattern was most pronounced for ants that discovered resources. Body size and pronotum width responded as predicted for experimental treatments, but were inconsistent across continents. Monopolising ants were smaller, with shorter femurs than those that occupied or discovered resources. Consistent responses for several traits suggest that many, but not all, aspects of morphology respond predictably to habitat complexity, and that foraging strategy is linked with morphology. Some traits thus have the potential to be used to predict the direction of species turnover, changes in foraging strategy and, potentially, evolution in response to changes in habitat structure. PMID:23691137

Molecular Species Delimitation in the Racomitrium canescens Complex (Grimmiaceae) and Implications for DNA Barcoding of Species Complexes in Mosses

PubMed Central

Stech, Michael; Veldman, Sarina; Larraín, Juan; Muñoz, Jesús; Quandt, Dietmar; Hassel, Kristian; Kruijer, Hans

2013-01-01

In bryophytes a morphological species concept is still most commonly employed, but delimitation of closely related species based on morphological characters is often difficult. Here we test morphological species circumscriptions in a species complex of the moss genus Racomitrium, the R. canescens complex, based on variable DNA sequence markers from the plastid (rps4-trnT-trnL region) and nuclear (nrITS) genomes. The extensive morphological variability within the complex has led to different opinions about the number of species and intraspecific taxa to be distinguished. Molecular phylogenetic reconstructions allowed to clearly distinguish all eight currently recognised species of the complex plus a ninth species that was inferred to belong to the complex in earlier molecular analyses. The taxonomic significance of intraspecific sequence variation is discussed. The present molecular data do not support the division of the R. canescens complex into two groups of species (subsections or sections). Most morphological characters, albeit being in part difficult to apply, are reliable for species identification in the R. canescens complex. However, misidentification of collections that were morphologically intermediate between species questioned the suitability of leaf shape as diagnostic character. Four partitions of the molecular markers (rps4-trnT, trnT-trnL, ITS1, ITS2) that could potentially be used for molecular species identification (DNA barcoding) performed almost equally well concerning amplification and sequencing success. Of these, ITS1 provided the highest species discrimination capacity and should be considered as a DNA barcoding marker for mosses, especially in complexes of closely related species. Molecular species identification should be complemented by redefining morphological characters, to develop a set of easy-to-use molecular and non-molecular identification tools for improving biodiversity assessments and ecological research including mosses. PMID:23341927

Molecular Species Delimitation and Morphology of Aquatic and Sub-Aquatic Bugs (Heteroptera) in Cameroon

PubMed Central

Le Gall, Philippe; Chen, Ping-Ping; Nieser, Nico; Guilbert, Eric; Njiokou, Flobert; Marsollier, Laurent; Guégan, Jean-François; Pluot-Sigwalt, Dominique; Eyangoh, Sara; Harry, Myriam

2016-01-01

Aquatic and semi-aquatic bugs (Heteroptera) represent a remarkable diversity and a resurging interest has been given to documenting at the species level these insects inhabiting Cameroon in Central Africa due to their potential implication in the transmission of the bacterium Mycobacterium ulcerans, the causal agent of Buruli ulcer, an emerging human disease. A survey was carried out over two years in Cameroon. Morphological analyses were done in two steps. A first step consisted in separating the specimens based on broadly shared characters into morphotypes. The specimens were then separated into two independent batches containing each the same representation of each morphotype. One batch (309 specimens) was used by taxonomy experts on aquatic bugs for species level identification and/or to reconcile nymph with their corresponding adult species. The second batch (188 specimens) was used to define species based on the COI DNA sequences (standard sequence used for “DNA barcoding”) and using the Automatic Barcode Gap Discovery (ABGD) method. The first morphological analysis step separated the specimens into 63 different morphotypes (49 adults and 14 nymphs), which were then found to belong to 54 morphological species in the infra-orders Gerromorpha and Nepomorpha based on the species-level morphological identification, and 41–45 putative molecular species according to the gap value retained in the ABGD. Integrating morphology and “DNA barcoding” reconciled all the specimens into 62 aquatic bug species in Cameroon. Generally, we obtained a good congruence between species a priori identified based on morphology from adult morphotypes and molecular putative species. Moreover, molecular identification has allowed the association of 86% of nymphs with adults. This work illustrates the importance of integrative taxonomy. PMID:27149077

Recognition of finger flexion motion from ultrasound image: a feasibility study.

PubMed

Shi, Jun; Guo, Jing-Yi; Hu, Shu-Xian; Zheng, Yong-Ping

2012-10-01

Muscle contraction results in structural and morphologic changes of the related muscle. Therefore, finger flexion can be monitored from measurements of these morphologic changes. We used ultrasound imaging to record muscle activities during finger flexion and extracted features to discriminate different fingers' flexions using a support vector machine (SVM). Registration of ultrasound images before and after finger flexion was performed to generate a deformation field, from which angle features and wavelet-based features were extracted. The SVM was then used to classify the motions of different fingers. The experimental results showed that the overall mean recognition accuracy was 94.05% ± 4.10%, with the highest for the thumb (97%) and the lowest for the ring finger (92%) and the mean F value was 0.94 ± 0.02, indicating high accuracy and reliability of this method. The results suggest that the proposed method has the potential to be used as an alternative method of surface electromyography in differentiating the motions of different fingers. Copyright © 2012 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Physiological variation in left atrial transverse orientation does not influence orthogonal P-wave morphology.

PubMed

Petersson, Richard; Mosén, Henrik; Steding-Ehrenborg, Katarina; Carlson, Jonas; Faxén, Lisa; Mohtadi, Alan; Platonov, Pyotr G; Holmqvist, Fredrik

2017-03-01

It has previously been demonstrated that orthogonal P-wave morphology in healthy athletes does not depend on atrial size, but the possible impact of left atrial orientation on P-wave morphology remains unknown. In this study, we investigated if left atrial transverse orientation affects P-wave morphology in different populations. Forty-seven patients with atrial fibrillation, 21 patients with arrhythmogenic right ventricular cardiomyopathy, 67 healthy athletes, and 56 healthy volunteers were included. All underwent cardiac magnetic resonance imaging or computed tomography and the orientation of the left atrium was determined. All had 12-lead electrocardiographic recordings, which were transformed into orthogonal leads and orthogonal P-wave morphology was obtained. The median left atrial transverse orientation was 87 (83, 91) degrees (lower and upper quartiles) in the total study population. There was no difference in left atrial transverse orientation between individuals with different orthogonal P-wave morphologies. The physiological variation in left atrial orientation was small within as well as between the different populations. There was no difference in left atrial transverse orientation between subjects with type 1 and type 2 P-wave morphology, implying that in this setting the P-wave morphology was more dependent on atrial conduction than orientation. © 2016 Wiley Periodicals, Inc.

The complex evolutionary history of big-eared horseshoe bats (Rhinolophus macrotis complex): insights from genetic, morphological and acoustic data

PubMed Central

Sun, Keping; Kimball, Rebecca T.; Liu, Tong; Wei, Xuewen; Jin, Longru; Jiang, Tinglei; Lin, Aiqing; Feng, Jiang

2016-01-01

Palaeoclimatic oscillations and different landscapes frequently result in complex population-level structure or the evolution of cryptic species. Elucidating the potential mechanisms is vital to understanding speciation events. However, such complex evolutionary patterns have rarely been reported in bats. In China, the Rhinolophus macrotis complex contains a large form and a small form, suggesting the existence of a cryptic bat species. Our field surveys found these two sibling species have a continuous and widespread distribution with partial sympatry. However, their evolutionary history has received little attention. Here, we used extensive sampling, morphological and acoustic data, as well as different genetic markers to investigate their evolutionary history. Genetic analyses revealed discordance between the mitochondrial and nuclear data. Mitochondrial data identified three reciprocally monophyletic lineages: one representing all small forms from Southwest China, and the other two containing all large forms from Central and Southeast China, respectively. The large form showed paraphyly with respect to the small form. However, clustering analyses of microsatellite and Chd1 gene sequences support two divergent clusters separating the large form and the small form. Moreover, morphological and acoustic analyses were consistent with nuclear data. This unusual pattern in the R. macrotis complex might be accounted for by palaeoclimatic oscillations, shared ancestral polymorphism and/or interspecific hybridization. PMID:27748429

Artificial Metamorphosis: Evolutionary Design of Transforming, Soft-Bodied Robots.

PubMed

Joachimczak, Michał; Suzuki, Reiji; Arita, Takaya

2016-01-01

We show how the concept of metamorphosis, together with a biologically inspired model of multicellular development, can be used to evolve soft-bodied robots that are adapted to two very different tasks, such as being able to move in an aquatic and in a terrestrial environment. Each evolved solution defines two pairs of morphologies and controllers, together with a process of transforming one pair into the other. Animats develop from a single cell and grow through cellular divisions and deaths until they reach an initial larval form adapted to a first environment. To obtain the adult form adapted to a second environment, the larva undergoes metamorphosis, during which new cells are added or removed and its controller is modified. Importantly, our approach assumes nothing about what morphologies or methods of locomotion are preferred. Instead, it successfully searches the vast space of possible designs and comes up with complex, surprising, lifelike solutions that are reminiscent of amphibian metamorphosis. We analyze obtained solutions and investigate whether the morphological changes during metamorphosis are indeed adaptive. We then compare the effectiveness of three different types of selective pressures used to evolve metamorphic individuals. Finally, we investigate potential advantages of using metamorphosis to automatically produce soft-bodied designs by comparing the performance of metamorphic individuals with their specialized counterparts and designs that are robust to both environments.

Zirconium tungstate/epoxy nanocomposites: effect of nanoparticle morphology and negative thermal expansivity.

PubMed

Wu, Hongchao; Rogalski, Mark; Kessler, Michael R

2013-10-09

The ability to tailor the coefficient of thermal expansion (CTE) of a polymer is essential for mitigating thermal residual stress and reducing microcracks caused by CTE mismatch of different components in electronic applications. This work studies the effect of morphology and thermal expansivity of zirconium tungstate nanoparticles on the rheological, thermo-mechanical, dynamic-mechanical, and dielectric properties of ZrW2O8/epoxy nanocomposites. Three types of ZrW2O8 nanoparticles were synthesized under different hydrothermal conditions and their distinct properties were characterized, including morphology, particle size, aspect ratio, surface area, and CTE. Nanoparticles with a smaller particle size and larger surface area led to a more significant reduction in gel-time and glass transition temperature of the epoxy nanocomposites, while a higher initial viscosity and significant shear thinning behavior was found in prepolymer suspensions containing ZrW2O8 with larger particle sizes and aspect ratios. The thermo- and dynamic-mechanical properties of epoxy-based nanocomposites improved with increasing loadings of the three types of ZrW2O8 nanoparticles. In addition, the introduced ZrW2O8 nanoparticles did not negatively affect the dielectric constant or the breakdown strength of the epoxy resin, suggesting potential applications of ZrW2O8/epoxy nanocomposites in the microelectronic insulation industry.

Morphological Characterization of Thioflavin-S-Positive Amyloid Plaques in Transgenic Alzheimer Mice and Effect of Passive Aβ Immunotherapy on Their Clearance

PubMed Central

Bussière, Thierry; Bard, Frédérique; Barbour, Robin; Grajeda, Henry; Guido, Terry; Khan, Karen; Schenk, Dale; Games, Dora; Seubert, Peter; Buttini, Manuel

2004-01-01

Transgenic mice mimicking certain features of Alzheimer’s disease (AD)-pathology, namely amyloid plaques and neurofibrillary tangles, have been developed in an effort to better understand the mechanism leading to the formation of these characteristic cerebral lesions. More recently, these animal models have been widely used to investigate emergent therapies aimed at the reduction of the cerebral amyloid load. Several studies have shown that immunotherapy targeting the amyloid peptide (Aβ) is efficacious at clearing the amyloid plaques or preventing their formation, and at reducing the memory/behavior impairment observed in these animals. In AD, different types of plaques likely have different pathogenic significance, and further characterization of plaque pathology in the PDAPP transgenic mice would enhance the evaluation of potential therapeutics. In the present study, a morphological classification of amyloid plaques present in the brains of PDAPP mice was established by using Thioflavin-S staining. Neuritic dystrophy associated with amyloid plaques was also investigated. Finally, the efficacy of passive immunization with anti-Aβ antibodies on the clearance of Thio-S positive amyloid plaques was studied. Our results show that distinct morphological types of plaques are differentially cleared depending upon the isotype of the antibody. PMID:15331422

Microstructure and optical properties of nanocrystalline Cu2O thin films prepared by electrodeposition.

PubMed

Jiang, Xishun; Zhang, Miao; Shi, Shiwei; He, Gang; Song, Xueping; Sun, Zhaoqi

2014-01-01

Cuprous oxide (Cu2O) thin films were prepared by using electrodeposition technique at different applied potentials (-0.1, -0.3, -0.5, -0.7, and -0.9 V) and were annealed in vacuum at a temperature of 100°C for 1 h. Microstructure and optical properties of these films have been investigated by X-ray diffractometer (XRD), field-emission scanning electron microscope (SEM), UV-visible (vis) spectrophotometer, and fluorescence spectrophotometer. The morphology of these films varies obviously at different applied potentials. Analyses from these characterizations have confirmed that these films are composed of regular, well-faceted, polyhedral crystallites. UV-vis absorption spectra measurements have shown apparent shift in optical band gap from 1.69 to 2.03 eV as the applied potential becomes more cathodic. The emission of FL spectra at 603 nm may be assigned as the near band-edge emission.

Strip-bark and Whole-bark Siberian Pine Radial Growth Trends and Implications for Climate Reconstruction

NASA Astrophysics Data System (ADS)

Leland, C.; Cook, E. R.; Andreu-Hayles, L.; Pederson, N.; Hessl, A. E.; Anchukaitis, K. J.; Byambasuren, O.; Nachin, B.; Davi, N. K.; D'Arrigo, R.; Griffin, K. L.; Bishop, D. A.; Rao, M. P.

2017-12-01

Ancient trees can exhibit strip-bark morphology in which a portion of the cambium, the active layer of growth in the stem, dies in response to environmental stress. Partial cambial dieback has been linked to several different ecological and physiological factors, but the causes of dieback vary depending on site conditions. Further, the implications of such morphology on radial growth trends and its importance for tree-ring-based climate reconstructions remain unclear. We investigate the timing and potential environmental drivers of cambial dieback in Pinus sibirica trees from a xeric site in central Mongolia, and compare growth patterns of strip and whole-bark (full cambium) trees over the past 500 years. Cambial dieback occurred primarily on the southern side of trees, and was most common during the cold and dry 19th century. These unfavorable climatic conditions, combined with high exposure to solar radiation, suggested by the orientation of strip bark, might be responsible for cambial dieback. Increasing ring-width trends are gradual in most strip-bark trees, and do not immediately follow dieback dates detected for individual stems. However, a mean ring-width chronology of all strip-bark trees abruptly increases and significantly exceeds ring widths of coeval whole-bark trees in the early 20th century. After standardizing strip and whole-bark series to remove allometric trends, the differences in recent growth trends persist. Before using strip-bark trees for climate reconstruction, we suggest comparing strip and whole-bark ring-width trends in order to determine appropriate methods for removing potential morphology-related growth trends. We extend this study by analyzing stable carbon isotopes in tree rings to evaluate whether there are physiological differences between strip-bark and whole-bark trees, and to determine if δ13C can be used as an additional parameter for climate reconstruction.

Morphologies, Processing and Properties of Ceramic Foams and Their Potential as TPS Materials

NASA Technical Reports Server (NTRS)

Stackpoole, Mairead; Simoes, Conan R.; Johnson, Sylvia M.

2002-01-01

The current research is focused on processing ceramic foams with compositions that have potential as a thermal protection material. The use of pre-ceramic polymers with the addition of sacrificial blowing agents or sacrificial fillers offers a viable approach to form either open or closed cell insulation. Our work demonstrates that this is a feasible method to form refractory ceramic foams at relatively low processing temperatures. It is possible to foam complex shapes then pyrolize the system to form a ceramic while retaining the shape of the unfired foam. Initial work focused on identifying suitable pre-ceramic polymers with desired properties such as ceramic yield and chemical make up of the pyrolysis product after firing. We focused on making foams in the Si system (Sic, Si02, Si-0-C), which is in use in current acreage TPS systems. Ceramic foams with different architectures were formed from the pyrolysis of pre-ceramic polymers at 1200 C in different atmospheres. In some systems a sacrificial polyurethane was used as the blowing agent. We have also processed foams using sacrificial fillers to introduce controlled cell sizes. Each sacrificial filler or blowing agent leads to a unique morphology. The effect of different fillers on foam morphologies and the characterization of these foams in terms of mechanical and thermal properties are presented. We have conducted preliminary arc jet testing on selected foams with the materials being exposed to typical re-entry conditions for acreage TPS and these results will be discussed. Foams processed using these approaches have bulk densities ranging from 0.15 to 0.9 g/cm3 and cell sizes ranging from 5 to 500 pm. Compression strengths ranged from 2 to 7 MPa for these systems. Finally, preliminary oxidation studies have been conducted on selected systems and will be discussed.

The Limits on Trypanosomatid Morphological Diversity

PubMed Central

Wheeler, Richard John; Gluenz, Eva; Gull, Keith

2013-01-01

Cell shape is one, often overlooked, way in which protozoan parasites have adapted to a variety of host and vector environments and directional transmissions between these environments. Consequently, different parasite life cycle stages have characteristic morphologies. Trypanosomatid parasites are an excellent example of this in which large morphological variations between species and life cycle stage occur, despite sharing well-conserved cytoskeletal and membranous structures. Here, using previously published reports in the literature of the morphology of 248 isolates of trypanosomatid species from different hosts, we perform a meta-analysis of the occurrence and limits on morphological diversity of different classes of trypanosomatid morphology (trypomastigote, promastigote, etc.) in the vertebrate bloodstream and invertebrate gut environments. We identified several limits on cell body length, cell body width and flagellum length diversity which can be interpreted as biomechanical limits on the capacity of the cell to attain particular dimensions. These limits differed for morphologies with and without a laterally attached flagellum which we suggest represent two morphological superclasses, the ‘juxtaform’ and ‘liberform’ superclasses. Further limits were identified consistent with a selective pressure from the mechanical properties of the vertebrate bloodstream environment; trypanosomatid size showed limits relative to host erythrocyte dimensions. This is the first comprehensive analysis of the limits of morphological diversity in any protozoan parasite, revealing the morphogenetic constraints and extrinsic selection pressures associated with the full diversity of trypanosomatid morphology. PMID:24260255

Mandibular condylar morphology for bruxers with different grinding patterns.

PubMed

Tao, Jianxiang; Wu, Junhua; Zhang, Xuying

2015-12-29

The purpose of this study was to investigate the mandibular condylar morphology for bruxers with different grinding patterns. Condylar sectional morphology and condylar position of 30 subjects were determined by two viewers using cone beam computed tomography (CBCT) image data sets. The grinding patterns during sleep bruxism (SB) were determined objectively using a Brux-checker device.Chi-square tests were used for statistical analysis for the condylar morphology type between different tooth grinding patterns. Spearman's rank correlation coefficient was used for correlation analysis between condylar position and the canine guidance area during SB. Theincidence of condylarmorphologicaldivergence from idealwas35%.There isa significant difference in distribution of condylar morphology type between the group grinding (GG) and GG combined with mediotrusive side grinding (MG) (Pv 0.05). There was no significant correlation between condylar position and canine guidance area during bruxism. MG during SB is associated with condylar morphology that is considered not to be ideal.

Mandibular condylar morphology for bruxers with different grinding patterns.

PubMed

Tao, Jianxiang; Wu, Junhua; Zhang, Xuying

2016-07-01

The purpose of this study was to investigate the mandibular condylar morphology for bruxers with different grinding patterns. Condylar sectional morphology and condylar position of 30 subjects were determined by two viewers using cone beam computed tomography (CBCT) image data sets. The grinding patterns during sleep bruxism (SB) were determined objectively using a Brux-checker device.Chi-square tests were used for statistical analysis for the condylar morphology type between different tooth grinding patterns. Spearman's rank correlation coefficient was used for correlation analysis between condylar position and the canine guidance area during SB. Theincidence of condylarmorphologicaldivergence from idealwas35%.There isa significant difference in distribution of condylar morphology type between the group grinding (GG) and GG combined with mediotrusive side grinding (MG) (p < 0.05). There was no significant correlation between condylar position and canine guidance area during bruxism. MG during SB is associated with condylar morphology that is considered not to be ideal.

[MORPHOLOGICAL VARIABILITY OF PROTEOCEPHALUS PERCAE (MÜLLER 1780) PARASITIZING COREGONID FISHES].

PubMed

Anikieva, L V; Ieshko, E P; Lebedeva, D I

2015-01-01

Morphological variability of Proteocephalus percae from native host--perch Perca fluviatilis and two species of coregonids (whitefish Coregonus lavaretus and Arctic cisco C. autumnalis) from fish farms of Karelia were studied. Parasite groups from 3 host species differed by morphometric parameters. Morphological structure of P. percae from native host included three morphs, those numbers were almost equal. Parasite groups of whitefish and Arctic cisco differed from that of perch in morphological structure and dominance of different morphs. Changes of the P. percae morphological structure was related to differences in ecological niches of three hosts of parasite. This reflects the initial stages of microevolution. The results obtained allow us to estimate an adaptive response of parasitic worms to new host species settling to pond.

Spine Calcium Transients Induced by Synaptically-Evoked Action Potentials Can Predict Synapse Location and Establish Synaptic Democracy

PubMed Central

Meredith, Rhiannon M.; van Ooyen, Arjen

2012-01-01

CA1 pyramidal neurons receive hundreds of synaptic inputs at different distances from the soma. Distance-dependent synaptic scaling enables distal and proximal synapses to influence the somatic membrane equally, a phenomenon called “synaptic democracy”. How this is established is unclear. The backpropagating action potential (BAP) is hypothesised to provide distance-dependent information to synapses, allowing synaptic strengths to scale accordingly. Experimental measurements show that a BAP evoked by current injection at the soma causes calcium currents in the apical shaft whose amplitudes decay with distance from the soma. However, in vivo action potentials are not induced by somatic current injection but by synaptic inputs along the dendrites, which creates a different excitable state of the dendrites. Due to technical limitations, it is not possible to study experimentally whether distance information can also be provided by synaptically-evoked BAPs. Therefore we adapted a realistic morphological and electrophysiological model to measure BAP-induced voltage and calcium signals in spines after Schaffer collateral synapse stimulation. We show that peak calcium concentration is highly correlated with soma-synapse distance under a number of physiologically-realistic suprathreshold stimulation regimes and for a range of dendritic morphologies. Peak calcium levels also predicted the attenuation of the EPSP across the dendritic tree. Furthermore, we show that peak calcium can be used to set up a synaptic democracy in a homeostatic manner, whereby synapses regulate their synaptic strength on the basis of the difference between peak calcium and a uniform target value. We conclude that information derived from synaptically-generated BAPs can indicate synapse location and can subsequently be utilised to implement a synaptic democracy. PMID:22719238

Fitting membrane resistance along with action potential shape in cardiac myocytes improves convergence: application of a multi-objective parallel genetic algorithm.

PubMed

Kaur, Jaspreet; Nygren, Anders; Vigmond, Edward J

2014-01-01

Fitting parameter sets of non-linear equations in cardiac single cell ionic models to reproduce experimental behavior is a time consuming process. The standard procedure is to adjust maximum channel conductances in ionic models to reproduce action potentials (APs) recorded in isolated cells. However, vastly different sets of parameters can produce similar APs. Furthermore, even with an excellent AP match in case of single cell, tissue behaviour may be very different. We hypothesize that this uncertainty can be reduced by additionally fitting membrane resistance (Rm). To investigate the importance of Rm, we developed a genetic algorithm approach which incorporated Rm data calculated at a few points in the cycle, in addition to AP morphology. Performance was compared to a genetic algorithm using only AP morphology data. The optimal parameter sets and goodness of fit as computed by the different methods were compared. First, we fit an ionic model to itself, starting from a random parameter set. Next, we fit the AP of one ionic model to that of another. Finally, we fit an ionic model to experimentally recorded rabbit action potentials. Adding the extra objective (Rm, at a few voltages) to the AP fit, lead to much better convergence. Typically, a smaller MSE (mean square error, defined as the average of the squared error between the target AP and AP that is to be fitted) was achieved in one fifth of the number of generations compared to using only AP data. Importantly, the variability in fit parameters was also greatly reduced, with many parameters showing an order of magnitude decrease in variability. Adding Rm to the objective function improves the robustness of fitting, better preserving tissue level behavior, and should be incorporated.

The effects of interfacial potential on antimicrobial propensity of ZnO nanoparticle

PubMed Central

Arakha, Manoranjan; Saleem, Mohammed; Mallick, Bairagi C.; Jha, Suman

2015-01-01

The work investigates the role of interfacial potential in defining antimicrobial propensity of ZnO nanoparticle (ZnONP) against different Gram positive and Gram negative bacteria. ZnONPs with positive and negative surface potential are tested against different bacteria with varying surface potentials, ranging −14.7 to −23.6 mV. Chemically synthesized ZnONPs with positive surface potential show very high antimicrobial propensity with minimum inhibitory concentration of 50 and 100 μg/mL for Gram negative and positive bacterium, respectively. On other hand, ZnONPs of the same size but with negative surface potential show insignificant antimicrobial propensity against the studied bacteria. Unlike the positively charged nanoparticles, neither Zn2+ ion nor negatively charged ZnONP shows any significant inhibition in growth or morphology of the bacterium. Potential neutralization and colony forming unit studies together proved adverse effect of the resultant nano-bacterial interfacial potential on bacterial viability. Thus, ZnONP with positive surface potential upon interaction with negative surface potential of bacterial membrane enhances production of the reactive oxygen species and exerts mechanical stress on the membrane, resulting in the membrane depolarization. Our results show that the antimicrobial propensity of metal oxide nanoparticle mainly depends upon the interfacial potential, the potential resulting upon interaction of nanoparticle surface with bacterial membrane. PMID:25873247

Morphological and physical - chemical issues of metal nanostructures used in medical field

NASA Astrophysics Data System (ADS)

Duceac, L. D.; Velenciuc, N.; Dobre, E. C.

2016-06-01

In recent years applications of nanotechnology integrated into nanomedicine and bio-nanotechnology have attracted the attention of many researchers from different fields. Processes from chemical engineering especially nanostructured materials play an important role in medical and pharmaceutical development. Fundamental researches focused on finding simple, easily accomplished synthesis methods, morphological aspects and physico-chemical advanced characterization of nanomaterials. More over, by controlling synthesis conditions textural characteristics and physicochemical properties such as particle size, shape, surface, porosity, aggregation degree and composition can be tailored. Low cytotoxicity and antimicrobial effects of these nanostructured materials makes them be applied in medicine field. The major advantage of metal based nanoparticles is the use either for their antimicrobial properties or as drug-carriers having the potential to be active at low concentrations against infectious agents.

Acquiring 3-D information about thick objects from differential interference contrast images using texture extraction

NASA Astrophysics Data System (ADS)

Sierra, Heidy; Brooks, Dana; Dimarzio, Charles

2010-07-01

The extraction of 3-D morphological information about thick objects is explored in this work. We extract this information from 3-D differential interference contrast (DIC) images by applying a texture detection method. Texture extraction methods have been successfully used in different applications to study biological samples. A 3-D texture image is obtained by applying a local entropy-based texture extraction method. The use of this method to detect regions of blastocyst mouse embryos that are used in assisted reproduction techniques such as in vitro fertilization is presented as an example. Results demonstrate the potential of using texture detection methods to improve morphological analysis of thick samples, which is relevant to many biomedical and biological studies. Fluorescence and optical quadrature microscope phase images are used for validation.

Optimising low molecular weight hydrogels for automated 3D printing.

PubMed

Nolan, Michael C; Fuentes Caparrós, Ana M; Dietrich, Bart; Barrow, Michael; Cross, Emily R; Bleuel, Markus; King, Stephen M; Adams, Dave J

2017-11-22

Hydrogels prepared from low molecular weight gelators (LMWGs) are formed as a result of hierarchical intermolecular interactions between gelators to form fibres, and then further interactions between the self-assembled fibres via physical entanglements, as well as potential branching points. These interactions can allow hydrogels to recover quickly after a high shear rate has been applied. There are currently limited design rules describing which types of morphology or rheological properties are required for a LMWG hydrogel to be used as an effective, printable gel. By preparing hydrogels with different types of fibrous network structures, we have been able to understand in more detail the morphological type which gives rise to a 3D-printable hydrogel using a range of techniques, including rheology, small angle scattering and microscopy.

Controlled Self-Assembly of Low-Dimensional Alq3 Nanostructures from 1D Nanowires to 2D Plates via Intermolecular Interactions

NASA Astrophysics Data System (ADS)

Gu, Jianmin; Yin, Baipeng; Fu, Shaoyan; Jin, Cuihong; Liu, Xin; Bian, Zhenpan; Li, Jianjun; Wang, Lu; Li, Xiaoyu

2018-03-01

Due to the intense influence of the shape and size of the photon building blocks on the limitation and guidance of optical waves, an important strategy is the fabrication of different structures. Herein, organic semiconductor tris-(8-hydroxyquinoline)aluminium (Alq3) nanostructures with controllable morphology, ranging from one-dimensional nanowires to two-dimensional plates, have been prepared through altering intermolecular interactions with employing the anti-solvent diffusion cooperate with solvent-volatilization induced self-assembly method. The morphologies of the formed nanostructures, which are closely related to the stacking modes of the molecules, can be exactly controlled by altering the polarity of anti-solvents that can influence various intermolecular interactions. The synthesis strategy reported here can potentially be extended to other functional organic nanomaterials.

Effect of etching time on morphological, optical, and electronic properties of silicon nanowires.

PubMed

Nafie, Nesma; Lachiheb, Manel Abouda; Bouaicha, Mongi

2012-07-16

Owing to their interesting electronic, mechanical, optical, and transport properties, silicon nanowires (SiNWs) have attracted much attention, giving opportunities to several potential applications in nanoscale electronic, optoelectronic devices, and silicon solar cells. For photovoltaic application, a superficial film of SiNWs could be used as an efficient antireflection coating. In this work we investigate the morphological, optical, and electronic properties of SiNWs fabricated at different etching times. Characterizations of the formed SiNWs films were performed using a scanning electron microscope, ultraviolet-visible-near-infrared spectroscopy, and light-beam-induced-current technique. The latter technique was used to determine the effective diffusion length in SiNWs films. From these investigations, we deduce that the homogeneity of the SiNWs film plays a key role on the electronic properties.

Relevance of chemistry to conservation of isolated populations: the case of volatile leaf components of Dicerandra mints.

PubMed Central

McCormick, K D; Deyrup, M A; Menges, E S; Wallace, S R; Meinwald, J; Eisner, T

1993-01-01

Chemical analysis of the essential oils of four congeneric species of mint plant (Dicerandra spp.) endemic to Florida revealed a pattern of chemical similarity and dissimilarity that would not have been predicted on morphological or geographic criteria. Dicerandra christmanii differs fundamentally from its congeners in that it produces fewer compounds and lacks the acyclic components. Yet D. christmanii is more closely similar to Dicerandra frutescens than to other Dicerandra species in morphological characters and geographic range. We conclude that the potential chemical value of a species should not be prejudged on the basis of nonchemical characters and that designation of surplus plant populations by conservationists should be resisted unless such populations have also been chemically studied. Images Fig. 2 PMID:8356072

Controlled synthesis of silver nanostructures stabilized by fluorescent polyarylene ether nitrile

NASA Astrophysics Data System (ADS)

Jia, Kun; Shou, Hongguo; Wang, Pan; Zhou, Xuefei; Liu, Xiaobo

2016-07-01

In this work, the intrinsically fluorescent polyarylene ether nitrile (PEN) was explored to realize the controlled synthesis of fluorescent silver nanostructures with different morphology for the first time. Specifically, it was found that silver nitrate (AgNO3) can be effectively reduced to silver nanoparticles using PEN as both reducing and surface capping agents in N, N-dimethylformamide (DMF). More interestingly, the morphology of obtained fluorescent silver nanostructures can be tuned from nanospheres to nanorods by simple variation of reaction time at 130 °C using a relative PEN:AgNO3 molar concentration ratio of 1:8. Meanwhile, the obtained Ag nanostructures exhibited both localized surface plasmon resonance (LSPR) band and fluorescent emission around 420 nm, which would find potential applications in biochemical sensing and optical devices fields.

The strength of negative plant-soil feedback increases from the intraspecific to the interspecific and the functional group level.

PubMed

Bukowski, Alexandra R; Schittko, Conrad; Petermann, Jana S

2018-02-01

One of the processes that may play a key role in plant species coexistence and ecosystem functioning is plant-soil feedback, the effect of plants on associated soil communities and the resulting feedback on plant performance. Plant-soil feedback at the interspecific level (comparing growth on own soil with growth on soil from different species) has been studied extensively, while plant-soil feedback at the intraspecific level (comparing growth on own soil with growth on soil from different accessions within a species) has only recently gained attention. Very few studies have investigated the direction and strength of feedback among different taxonomic levels, and initial results have been inconclusive, discussing phylogeny, and morphology as possible determinants. To test our hypotheses that the strength of negative feedback on plant performance increases with increasing taxonomic level and that this relationship is explained by morphological similarities, we conducted a greenhouse experiment using species assigned to three taxonomic levels (intraspecific, interspecific, and functional group level). We measured certain fitness-related aboveground traits and used them along literature-derived traits to determine the influence of morphological similarities on the strength and direction of the feedback. We found that the average strength of negative feedback increased from the intraspecific over the interspecific to the functional group level. However, individual accessions and species differed in the direction and strength of the feedback. None of our results could be explained by morphological dissimilarities or individual traits. Synthesis . Our results indicate that negative plant-soil feedback is stronger if the involved plants belong to more distantly related species. We conclude that the taxonomic level is an important factor in the maintenance of plant coexistence with plant-soil feedback as a potential stabilizing mechanism and should be addressed explicitly in coexistence research, while the traits considered here seem to play a minor role.

Quantification of Dynamic Morphological Drug Responses in 3D Organotypic Cell Cultures by Automated Image Analysis

PubMed Central

Härmä, Ville; Schukov, Hannu-Pekka; Happonen, Antti; Ahonen, Ilmari; Virtanen, Johannes; Siitari, Harri; Åkerfelt, Malin; Lötjönen, Jyrki; Nees, Matthias

2014-01-01

Glandular epithelial cells differentiate into complex multicellular or acinar structures, when embedded in three-dimensional (3D) extracellular matrix. The spectrum of different multicellular morphologies formed in 3D is a sensitive indicator for the differentiation potential of normal, non-transformed cells compared to different stages of malignant progression. In addition, single cells or cell aggregates may actively invade the matrix, utilizing epithelial, mesenchymal or mixed modes of motility. Dynamic phenotypic changes involved in 3D tumor cell invasion are sensitive to specific small-molecule inhibitors that target the actin cytoskeleton. We have used a panel of inhibitors to demonstrate the power of automated image analysis as a phenotypic or morphometric readout in cell-based assays. We introduce a streamlined stand-alone software solution that supports large-scale high-content screens, based on complex and organotypic cultures. AMIDA (Automated Morphometric Image Data Analysis) allows quantitative measurements of large numbers of images and structures, with a multitude of different spheroid shapes, sizes, and textures. AMIDA supports an automated workflow, and can be combined with quality control and statistical tools for data interpretation and visualization. We have used a representative panel of 12 prostate and breast cancer lines that display a broad spectrum of different spheroid morphologies and modes of invasion, challenged by a library of 19 direct or indirect modulators of the actin cytoskeleton which induce systematic changes in spheroid morphology and differentiation versus invasion. These results were independently validated by 2D proliferation, apoptosis and cell motility assays. We identified three drugs that primarily attenuated the invasion and formation of invasive processes in 3D, without affecting proliferation or apoptosis. Two of these compounds block Rac signalling, one affects cellular cAMP/cGMP accumulation. Our approach supports the growing needs for user-friendly, straightforward solutions that facilitate large-scale, cell-based 3D assays in basic research, drug discovery, and target validation. PMID:24810913

The potential influence of morphology on the evolutionary divergence of an acoustic signal

PubMed Central

Pitchers, W. R.; Klingenberg, C.P.; Tregenza, Tom; Hunt, J.; Dworkin, I.

2014-01-01

The evolution of acoustic behaviour and that of the morphological traits mediating its production are often coupled. Lack of variation in the underlying morphology of signalling traits has the potential to constrain signal evolution. This relationship is particularly likely in field crickets, where males produce acoustic advertisement signals to attract females by stridulating with specialized structures on their forewings. In this study, we characterise the size and geometric shape of the forewings of males from six allopatric populations of the black field cricket (Teleogryllus commodus) known to have divergent advertisement calls. We sample from each of these populations using both wild-caught and common-garden reared cohorts, allowing us to test for multivariate relationships between wing morphology and call structure. We show that the allometry of shape has diverged across populations. However, there was a surprisingly small amount of covariation between wing shape and call structure within populations. Given the importance of male size for sexual selection in crickets, the divergence we observe among populations has the potential to influence the evolution of advertisement calls in this species. PMID:25223712

Changes in intrinsic excitability of ganglion cells in degenerated retinas of RCS rats.

PubMed

Ren, Yi-Ming; Weng, Chuan-Huang; Zhao, Cong-Jian; Yin, Zheng-Qin

2018-01-01

To evaluate the intrinsic excitability of retinal ganglion cells (RGCs) in degenerated retinas. The intrinsic excitability of various morphologically defined RGC types using a combination of patch-clamp recording and the Lucifer yellow tracer in retinal whole-mount preparations harvested from Royal College of Surgeons (RCS) rats, a common retinitis pigmentosa (RP) model, in a relatively late stage of retinal degeneration (P90) were investigated. Several parameters of RGC morphologies and action potentials (APs) were measured and compared to those of non-dystrophic control rats, including dendritic stratification, dendritic field diameter, peak amplitude, half width, resting membrane potential, AP threshold, depolarization to threshold, and firing rates. Compared with non-dystrophic control RGCs, more depolarizations were required to reach the AP threshold in RCS RGCs with low spontaneous spike rates and in RCS OFF cells (especially A2o cells), and RCS RGCs maintained their dendritic morphologies, resting membrane potentials and capabilities to generate APs. RGCs are relatively well preserved morphologically and functionally, and some cells are more susceptible to decreased excitability during retinal degeneration. These findings provide valuable considerations for optimizing RP therapeutic strategies.

Calcium carbonates: induced biomineralization with controlled macromorphology

NASA Astrophysics Data System (ADS)

Meier, Aileen; Kastner, Anne; Harries, Dennis; Wierzbicka-Wieczorek, Maria; Majzlan, Juraj; Büchel, Georg; Kothe, Erika

2017-11-01

Biomineralization of (magnesium) calcite and vaterite by bacterial isolates has been known for quite some time. However, the extracellular precipitation has hardly ever been linked to different morphologies of the minerals that are observed. Here, isolates from limestone-associated groundwater, rock and soil were shown to form calcite, magnesium calcite or vaterite. More than 92 % of isolates were indeed able to form carbonates, while abiotic controls failed to form minerals. The crystal morphologies varied, including rhombohedra, prisms and pyramid-like macromorphologies. Different conditions like varying temperature, pH or media components, but also cocultivation to test for collaborative effects of sympatric bacteria, were used to differentiate between mechanisms of calcium carbonate formation. Single crystallites were cemented with bacterial cells; these may have served as nucleation sites by providing a basic pH at short distance from the cells. A calculation of potential calcite formation of up to 2 g L-1 of solution made it possible to link the microbial activity to geological processes.

Total coliphages removal by activated sludge process and their morphological diversity by transmission electron microscopy.

PubMed

Jebri, Sihem; Hmaied, Fatma; Yahya, Mariem; Ben Ammar, Aouatef; Hamdi, Moktar

This study was conducted to isolate phages in treated sewage collected from wastewater treatment plant, and explore their morphological diversity by transmission electron microscopy (TEM). Fates of total bacteriophages and their reduction by biological treatment were also assayed. Phages were isolated using the plaque assay then negatively stained and observed by electron microscope. Electron micrographs showed different types of phages with different shapes and sizes. The majority of viruses found in treated sewage ranged from 30 to 100 nm in capsid diameter. Many of them were tailed, belonging to Siphoviridae, Myoviridae and Podoviridae families. Non-tailed phage particles were also found at a low rate, presumably belonging to Leviviridae or Microviridae families. This study shows the diversity and the abundance of bacteriophages in wastewater after biological treatment. Their persistence in wastewater reused in agriculture should raise concerns about their potential role in controlling bacterial populations in the environment. They should be also included in water treatment quality controlling guidelines as fecal and viral indicators.

pH Triggered Recovery and Reuse of Thiolated Poly(acrylic acid) Functionalized Gold Nanoparticles with Applications in Colloidal Catalysis.

PubMed

Ansar, Siyam M; Fellows, Benjamin; Mispireta, Patrick; Mefford, O Thompson; Kitchens, Christopher L

2017-08-08

Thiolated poly(acrylic acid) (PAA-SH) functionalized gold nanoparticles were explored as a colloidal catalyst with potential application as a recoverable catalyst where the PAA provides pH-responsive dispersibility and phase transfer capability between aqueous and organic media. This system demonstrates complete nanoparticle recovery and redispersion over multiple reaction cycles without changes in nanoparticle morphology or reduction in conversion. The catalytic activity (rate constant) was reduced in subsequent reactions when recovery by aggregation was employed, despite unobservable changes in morphology or dispersibility. When colloidal catalyst recovery employed a pH induced phase transfer between two immiscible solvents, the catalytic activity of the recovered nanoparticles was unchanged over four cycles, maintaining the original rate constant and 100% conversion. The ability to recover and reuse colloidal catalysts by aggregation/redispersion and phase transfer methods that occur at low and high pH, respectively, could be used for different gold nanoparticle catalyzed reactions that occur at different pH conditions.

A First Survey on the Abundance of Plastics Fragments and Particles on Two Sandy Beaches in Kuching, Sarawak, Malaysia

NASA Astrophysics Data System (ADS)

Noik, V. James; Mohd Tuah, P.

2015-04-01

Plastic fragments and particles as an emerging environmental contaminant and pollutant are gaining scientific attention in the recent decades due to the potential threats on biota. This study aims to elucidate the presence, abundance and temporal change of plastic fragments and particles from two selected beaches, namely Santubong and Trombol in Kuching on two sampling times. Morphological and polymer identification assessment on the recovered plastics was also conducted. Overall comparison statistical analysis revealed that the abundance of plastic fragments/debris on both of sampling stations were insignificantly different (p>0.05). Likewise, statistical analysis on the temporal changes on the abundance yielded no significant difference for most of the sampling sites on each respective station, except STB-S2. Morphological studies revealed physical features of plastic fragments and debris were diverse in shapes, sizes, colors and surface fatigues. FTIR fingerprinting analysis shows that polypropylene and polyethylene were the dominant plastic polymers debris on both beaches.

Humeral loads during swimming and walking in turtles: implications for morphological change during aquatic reinvasions.

PubMed

Young, Vanessa K H; Wienands, Charlotte E; Wilburn, Brittany P; Blob, Richard W

2017-11-01

During evolutionary reinvasions of water by terrestrial vertebrates, ancestrally tubular limb bones often flatten to form flippers. Differences in skeletal loading between land and water might have facilitated such changes. In turtles, femoral shear strains are significantly lower during swimming than during walking, potentially allowing a release from loads favoring tubular shafts. However, flipper-like morphology in specialized tetrapod swimmers is most accentuated in the forelimbs. To test whether the forelimbs of turtles also experience reduced torsional loading in water, we compared strains on the humerus of river cooters ( Pseudemys concinna ) between swimming and terrestrial walking. We found that humeral shear strains are also lower during swimming than during terrestrial walking; however, this appears to relate to a reduction in overall strain magnitude, rather than a specific reduction in twisting. These results indicate that shear strains show similar reductions between swimming and walking for forelimb and hindlimb, but these reductions are produced through different mechanisms. © 2017. Published by The Company of Biologists Ltd.

Morphological effects of porous poly-d,l-lactic acid/hydroxyapatite scaffolds produced by supercritical CO2 foaming on their mechanical performance.

PubMed

Rouholamin, Davood; van Grunsven, William; Reilly, Gwendolen C; Smith, Patrick J

2016-08-01

A novel supercritical CO2 foaming technique was used to fabricate scaffolds of controllable morphology and mechanical properties, with the potential to tailor the scaffolds to specific tissue engineering applications. Biodegradable scaffolds are widely used as temporary supportive structures for bone regeneration. The scaffolds must provide a sufficient mechanical support while allowing cell attachment and growth as well as metabolic activities. In this study, supercritical CO2 foaming was used to prepare fully interconnected porous scaffolds of poly-d,l-lactic acid and poly-d,l-lactic acid/hydroxyapatite. The morphological, mechanical and cell behaviours of the scaffolds were measured to examine the effect of hydroxyapatite on these properties. These scaffolds showed an average porosity in the range of 86%-95%, an average pore diameter of 229-347 µm and an average pore interconnection of 103-207 µm. The measured porosity, pore diameter, and interconnection size are suitable for cancellous bone regeneration. Compressive strength and modulus of up to 36.03 ± 5.90 and 37.97 ± 6.84 MPa were measured for the produced porous scaffolds of various compositions. The mechanical properties presented an improvement with the addition of hydroxyapatite to the structure. The relationship between morphological and mechanical properties was investigated. The matrices with different compositions were seeded with bone cells, and all the matrices showed a high cell viability and biocompatibility. The number of cells attached on the matrices slightly increased with the addition of hydroxyapatite indicating that hydroxyapatite improves the biocompatibility and proliferation of the scaffolds. The produced poly-d,l-lactic acid/hydroxyapatite scaffolds in this study showed a potential to be used as bone graft substitutes. © IMechE 2016.

Nuclear microsatellite variation in Malagasy baobabs (Adansonia, Bombacoideae, Malvaceae) reveals past hybridization and introgression.

PubMed

Leong Pock Tsy, Jean-Michel; Lumaret, Roselyne; Flaven-Noguier, Elodie; Sauve, Mathieu; Dubois, Marie-Pierre; Danthu, Pascal

2013-12-01

Adansonia comprises nine species, six of which are endemic to Madagascar. Genetic relationships between the Malagasy species remain unresolved due to conflicting results between nuclear and plastid DNA variation. Morphologically intermediate individuals between distinct species have been identified, indicative of interspecific hybridization. In this paper, microsatellite data are used to identify potential cases of hybridization and to provide insights into the evolutionary history of the genus on Madagascar. Eleven microsatellites amplified with new primers developed for Adansonia rubrostipa were used to analyse 672 individuals collected at 27 sites for the six Malagasy species and morphologically intermediate individuals. Rates of individual admixture were examined using three Bayesian clustering programs, STRUCTURE, BAPS and NewHybrids, with no a priori species assignment. Population differentiation was coherent, with recognized species boundaries. In the four Malagasy species of section Longitubae, 8·0, 9·0 and 9·5 % of individuals with mixed genotypes were identified by BAPS, NewHybrids and STRUCTURE, respectively. At sites with sympatric populations of A. rubrostipa and A. za, NewHybrids indicated these individuals to be F2 and, predominantly, backcrosses with both parental species. In northern Madagascar, two populations of trees combining A. za and A. perrieri morphology and microsatellite alleles were identified in the current absence of the parental species. The clear genetic differentiation observed between the six species may reflect their adaptation to different assortments of climate regimes and habitats during the colonization of the island. Microsatellite variation reveals that hybridization probably occurred in secondary contact between species of section Longitubae. This type of hybridization may also have been involved in the differentiation of a local new stabilized entity showing specific microsatellite alleles and morphological characters, suggesting a potential role of hybridization in the recent history of diversification on Madagascar.

A Genome-Wide Association Study Identifies Five Loci Influencing Facial Morphology in Europeans

PubMed Central

Liu, Fan; van der Lijn, Fedde; Schurmann, Claudia; Zhu, Gu; Chakravarty, M. Mallar; Hysi, Pirro G.; Wollstein, Andreas; Lao, Oscar; de Bruijne, Marleen; Ikram, M. Arfan; van der Lugt, Aad; Rivadeneira, Fernando; Uitterlinden, André G.; Hofman, Albert; Niessen, Wiro J.; Homuth, Georg; de Zubicaray, Greig; McMahon, Katie L.; Thompson, Paul M.; Daboul, Amro; Puls, Ralf; Hegenscheid, Katrin; Bevan, Liisa; Pausova, Zdenka; Medland, Sarah E.; Montgomery, Grant W.; Wright, Margaret J.; Wicking, Carol; Boehringer, Stefan; Spector, Timothy D.; Paus, Tomáš; Martin, Nicholas G.; Biffar, Reiner; Kayser, Manfred

2012-01-01

Inter-individual variation in facial shape is one of the most noticeable phenotypes in humans, and it is clearly under genetic regulation; however, almost nothing is known about the genetic basis of normal human facial morphology. We therefore conducted a genome-wide association study for facial shape phenotypes in multiple discovery and replication cohorts, considering almost ten thousand individuals of European descent from several countries. Phenotyping of facial shape features was based on landmark data obtained from three-dimensional head magnetic resonance images (MRIs) and two-dimensional portrait images. We identified five independent genetic loci associated with different facial phenotypes, suggesting the involvement of five candidate genes—PRDM16, PAX3, TP63, C5orf50, and COL17A1—in the determination of the human face. Three of them have been implicated previously in vertebrate craniofacial development and disease, and the remaining two genes potentially represent novel players in the molecular networks governing facial development. Our finding at PAX3 influencing the position of the nasion replicates a recent GWAS of facial features. In addition to the reported GWA findings, we established links between common DNA variants previously associated with NSCL/P at 2p21, 8q24, 13q31, and 17q22 and normal facial-shape variations based on a candidate gene approach. Overall our study implies that DNA variants in genes essential for craniofacial development contribute with relatively small effect size to the spectrum of normal variation in human facial morphology. This observation has important consequences for future studies aiming to identify more genes involved in the human facial morphology, as well as for potential applications of DNA prediction of facial shape such as in future forensic applications. PMID:23028347

A Bigger Picture: Organismal Function at the Nexus of Development, Ecology, and Evolution: An Introduction to the Symposium.

PubMed

Gignac, P M; Santana, S E

2016-09-01

Over the past 40 years of research, two perspectives have dominated the study of ecomorphology at ontogenetic and evolutionary timescales. For key anatomical complexes (e.g., feeding apparatus, locomotor systems, sensory structures), morphological changes during ontogeny are often interpreted in functional terms and linked to their putative importance for fitness. Across larger timescales, morphological transformations in these complexes are examined through character stability or mutability during cladogenesis. Because the fittest organisms must pass through ontogenetic changes in size and shape, addressing transformations in morphology at different time scales, from life histories to macroevolution, has the potential to illuminate major factors contributing to phenotypic diversity. To date, most studies have relied on the assumption that organismal form is tightly constrained by the adult niche. Although this could be accurate for organisms that rapidly reach and spend a substantial portion of their life history at the adult phenotype (e.g., birds, mammals), it may not always hold true for species that experience substantial growth after one or more major fitness filters during their ontogeny (e.g., some fishes, reptiles). In such circumstances, examining the adult phenotype as the primary result of selective processes may be erroneous as it likely obscures the developmental configuration of morphology that was most critical to early survival. Given this discrepancy-and its potential to mislead interpretations of how selection may shape a taxon's phenotype-this symposium addresses the question: how do we identify such ontogenetic "inertia," and how do we integrate developmental information into our phylogenetic, ecological, and functional interpretations of complex phenotypes? © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Repeated Stand-Replacing Crown Fires Affect Seed Morphology and Germination in Aleppo pine

PubMed Central

Saracino, Antonio; Bellino, Alessandro; Allevato, Emilia; Mingo, Antonio; Conti, Stefano; Rossi, Sergio; Bonanomi, Giuliano; Carputo, Domenico; Mazzoleni, Stefano

2017-01-01

Post-fire reproductive niche of Aleppo pine (Pinus halepensis) is deeply interlaced with fire products. Indeed, the high pH and low osmotic potentials of ash beds under burnt crowns constitute the main constraints to seed germination. In this study, we aim to investigate whether fire recurrence, through the physico-chemical constraints imposed by the ash beds, affects the reproduction ability of P. halepensis at the germination stage. To this aim, Aleppo pine seeds were collected in neighboring even-aged stands subjected to 0, 1, or 2 fires (namely fire cohorts), and seed morphology and germination performance, in terms of cumulative germination and germination kinetics, were studied under increasing osmotic potentials (from 0.0 to −1.2 MPa) and pH (from 6 to 11). Besides fire history, the role of ontogenetic age of mother plants on seed morphology and germination was also investigated. Differences in seed morphology among the three cohorts have been highlighted in a multivariate context, with anisotropic enlargement of the seeds produced by pine stands experiencing repeated fires. The patterns of seed germination varied primarily in relation to the fire cohort, with seeds from the pine stand experiencing repeated fires exhibiting enhanced tolerance to pH stress. Conversely, germination performances under osmotic constraints mainly depends on tree ontogenetic stage, with an involvement of fire history especially in the timing of seed germination. Our results suggest that, at least in the short term, fire recurrence does not constrain the reproduction ability of Aleppo pine. These results highlight the need for further research to elucidate the mechanisms behind these responses to recurrent fires. PMID:28713415

Major Crop Species Show Differential Balance between Root Morphological and Physiological Responses to Variable Phosphorus Supply

PubMed Central

Lyu, Yang; Tang, Hongliang; Li, Haigang; Zhang, Fusuo; Rengel, Zed; Whalley, William R.; Shen, Jianbo

2016-01-01

The relationship between root morphological and physiological responses to variable P supply in different plant species is poorly understood. We compared root morphological and physiological responses to P supply in seven crop species (Zea mays, Triticum aestivum, Brassica napus, Lupinus albus, Glycine max, Vicia faba, Cicer arietinum) treated with or without 100 mg P kg-1 in two soils (acidic and calcareous). Phosphorus deficiency decreased root length more in fibrous root species (Zea mays, Triticum aestivum, Brassica napus) than legumes. Zea mays and Triticum aestivum had higher root/shoot biomass ratio and Brassica napus had higher specific root length compared to legumes, whereas legumes (except soybean) had higher carboxylate exudation than fibrous root species. Lupinus albus exhibited the highest P-acquisition efficiency due to high exudation of carboxylates and acid phosphatases. Lupinus albus and Cicer arietinum depended mostly on root exudation (i.e., physiological response) to enhance P acquisition, whereas Zea mays, Triticum aestivum and Brassica napus had higher root morphology dependence, with Glycine max and Vicia faba in between. Principal component analysis using six morphological and six physiological responses identified root size and diameter as the most important morphological traits, whereas important physiological responses included carboxylate exudation, and P-acquisition and P-utilization efficiency followed by rhizosphere soil pH and acid phosphatase activity. In conclusion, plant species can be grouped on the basis of their response to soil P being primarily via root architectural or exudation plasticity, suggesting a potential benefit of crop-specific root-trait-based management to cope with variable soil P supply in sustainable grain production. PMID:28066491

3D geometric morphometric analysis of the proximal epiphysis of the hominoid humerus

PubMed Central

Arias-Martorell, Julia; Potau, Josep Maria; Bello-Hellegouarch, Gaëlle; Pastor, Juan Francisco; Pérez-Pérez, Alejandro

2012-01-01

In this study we perform a three-dimensional geometric morphometric (3D GM) analysis of the proximal epiphysis of the humerus in extant great apes, including humans, in order to accurately describe the functional anatomical differences between these taxa. In addition, a fossil hominin specimen of Australopithecus afarensis was included in a multivariate GM analysis in order to test the potential of this methodological approach for making locomotor inferences from fossil remains. The results obtained show significant differences in proximal humeral morphology among the taxa studied, which had thus far largely remained unnoticed. Based on morphofunctional considerations, these anatomical differences can be correlated to differences in the locomotor repertoires of the taxa, thus confirming that the proximal humerus is suitable for constructing paleobiological inferences about locomotion. Modern humans display markedly divergent features, which set them apart from both the extant great apes and the fossil hominin A. afarensis. The morphology of the proximal epiphysis of the humerus of the latter more closely resembles that of the orangutans, thus suggesting that despite hindlimb adaptations to bipedalism, the forelimb of this taxon was still functionally involved in arboreal behaviors, such as climbing or suspension. PMID:22946496

Temporal and spatial variation of morphological descriptors for atmospheric aerosols collected in Mexico City

NASA Astrophysics Data System (ADS)

China, S.; Mazzoleni, C.; Dubey, M. K.; Chakrabarty, R. K.; Moosmuller, H.; Onasch, T. B.; Herndon, S. C.

2010-12-01

We present an analysis of morphological characteristics of atmospheric aerosol collected during the MILAGRO (Megacity Initiative: Local and Global Research Observations) field campaign that took place in Mexico City in March 2006. The sampler was installed on the Aerodyne mobile laboratory. The aerosol samples were collected on nuclepore clear polycarbonate filters mounted in Costar pop-top membrane holders. More than one hundred filters were collected at different ground sites with different atmospheric and geographical characteristics (urban, sub-urban, mountain-top, industrial, etc.) over a month period. Selected subsets of these filters were analyzed for aerosol morphology using a scanning electron microscope and image analysis techniques. In this study we investigate spatial and temporal variations of aerosol shape descriptors, morphological parameters, and fractal dimension. We also compare the morphological results with other aerosol measurements such as aerosol optical properties(scattering and absorption) and size distribution data. Atmospheric aerosols have different morphological characteristics depending on many parameters such as emission sources, atmospheric formation pathways, aging processes, and aerosol mixing state. The aerosol morphology influences aerosol chemical and mechanical interactions with the environment, physical properties, and radiative effects. In this study, ambient aerosol particles have been classified in different shape groups as spherical, irregularly shaped, and fractal-like aggregates. Different morphological parameters such as aspect ratio, roundness, feret diameter, etc. have been estimated for irregular shaped and spherical particles and for different kinds of soot particles including fresh soot, collapsed and coated soot. Fractal geometry and image processing have been used to obtain morphological characteristics of different soot particles. The number of monomers constituting each aggregate and their diameters were measured and used to estimate an ensemble three-dimensional (3-d) fractal dimension. One-dimensional (1-d) and two-dimensional (2-d) fractal geometries have been measured using a power-law scaling relationship between 1-d and 2-d properties of projected images. Temporal variations in fractal dimension of soot-like aggregates have been observed at the mountaintop site and spatial variation of fractal dimension and other morphological descriptors of different shaped particles have been investigated for the different ground sites.

Morphological Variability in Second Language Learners: An Examination of Electrophysiological and Production Data

ERIC Educational Resources Information Center

Alemán Bañón, José; Miller, David; Rothman, Jason

2017-01-01

We examined sources of morphological variability in second language (L2) learners of Spanish whose native language (L1) is English, with a focus on L1-L2 similarity, morphological markedness, and knowledge type (receptive vs. expressive). Experiment 1 uses event-related potentials to examine noun-adjective number (present in L1) and gender…

Anticancer potential of Conium maculatum extract against cancer cells in vitro: Drug-DNA interaction and its ability to induce apoptosis through ROS generation.

PubMed

Mondal, Jesmin; Panigrahi, Ashis Kumar; Khuda-Bukhsh, Anisur Rahman

2014-08-01

Conium maculatum extract is used as a traditional medicine for cervix carcinoma including homeopathy. However, no systematic work has so far been carried out to test its anti-cancer potential against cervix cancer cells in vitro. Thus, in this study, we investigated whether ethanolic extract of conium is capable of inducing cytotoxicity in different normal and cancer cell lines including an elaborate study in HeLa cells. Conium's effects on cell cycle, reactive oxygen species (ROS) accumulation, mitochondrial membrane potential (MMP) and apoptosis, if any, were analyzed through flow cytometry. Whether Conium could damage DNA and induce morphological changes were also determined microscopically. Expression of different proteins related to cell death and survival was critically studied by western blotting and ELISA methods. If Conium could interact directly with DNA was also determined by circular dichroism (CD) spectroscopy. Conium treatment reduced cell viability and colony formation at 48 h and inhibited cell proliferation, arresting cell cycle at sub-G stage. Conium treatment lead to increased generation of reactive oxygen species (ROS) at 24 h, increase in MMP depolarization, morphological changes and DNA damage in HeLa cells along with externalization of phosphatidyl serine at 48 hours. While cytochrome c release and caspase-3 activation led HeLa cells toward apoptosis, down-regulation of Akt and NFkB inhibited cellular proliferation, indicating the signaling pathway to be mediated via the mitochondria-mediated caspase-3-dependent pathway. CD-spectroscopy revealed that Conium interacted with DNA molecule. Overall results validate anti-cancer potential of Conium and provide support for its use in traditional systems of medicine.

Anticancer potential of Conium maculatum extract against cancer cells in vitro: Drug-DNA interaction and its ability to induce apoptosis through ROS generation

PubMed Central

Mondal, Jesmin; Panigrahi, Ashis Kumar; Khuda-Bukhsh, Anisur Rahman

2014-01-01

Objective: Conium maculatum extract is used as a traditional medicine for cervix carcinoma including homeopathy. However, no systematic work has so far been carried out to test its anti-cancer potential against cervix cancer cells in vitro. Thus, in this study, we investigated whether ethanolic extract of conium is capable of inducing cytotoxicity in different normal and cancer cell lines including an elaborate study in HeLa cells. Materials and Methods: Conium's effects on cell cycle, reactive oxygen species (ROS) accumulation, mitochondrial membrane potential (MMP) and apoptosis, if any, were analyzed through flow cytometry. Whether Conium could damage DNA and induce morphological changes were also determined microscopically. Expression of different proteins related to cell death and survival was critically studied by western blotting and ELISA methods. If Conium could interact directly with DNA was also determined by circular dichroism (CD) spectroscopy. Results: Conium treatment reduced cell viability and colony formation at 48 h and inhibited cell proliferation, arresting cell cycle at sub-G stage. Conium treatment lead to increased generation of reactive oxygen species (ROS) at 24 h, increase in MMP depolarization, morphological changes and DNA damage in HeLa cells along with externalization of phosphatidyl serine at 48 hours. While cytochrome c release and caspase-3 activation led HeLa cells toward apoptosis, down-regulation of Akt and NFkB inhibited cellular proliferation, indicating the signaling pathway to be mediated via the mitochondria-mediated caspase-3-dependent pathway. CD-spectroscopy revealed that Conium interacted with DNA molecule. Conclusion: Overall results validate anti-cancer potential of Conium and provide support for its use in traditional systems of medicine. PMID:25298670

How well can spectroscopy predict leaf morphological traits in the seasonal neotropical savannas?

NASA Astrophysics Data System (ADS)

Streher, A. S.; McGill, B.; Morellato, P.; Silva, T. S. F.

2017-12-01

Variations in foliar morphological traits, quantified as leaf mass per area (LMA, g m-2) and leaf dry matter content (LDMC, g g-1), correspond to a tradeoff between investments in leaf construction costs and leaf life span. Leaf spectroscopy, the acquisition of reflected radiation along contiguous narrow spectral bands from leaves, has shown the potential to link leaf optical properties with a range of foliar traits. However, our knowledge is still limited on how well leaf traits from plants with different life forms and deciduousness strategies can be predicted from spectroscopy. To understand the relationships between leaf traits and optical properties, we investigated: 1) What are the spectral regions associated with leaf morphological traits? 2) How generalizable an optical trait model is across different life forms and leaf strategies? Five locations across cerrado and campo rupestre vegetation in Brazil were sampled during the growing season in 2017. Triplicate mature sun leaves were harvested from plants encompassing different life forms (grasses, perennial herbs, shrubs and trees), comprising 1650 individuals growing over a wide range of environmental conditions. For each individual, we determined LDMC and LMA, and took 30 spectral leaf measurements from 400 to 2500nm, using a spectrometer. We used the Random Forests (RF) algorithm to predict both morphological traits from leaf reflectance, and performed feature selection with a backward stepwise method, progressively removing variables with small importance at each iteration. Model performance was evaluated by using 10-fold cross-validation. LDMC values ranged from 0.12 to 0.67 g g-1, while LMA varied between 41.78 and 562 g m-2. The spectral bands that best explained trait variation were found within the SWIR, around 1397 nm for LDMC, and 2279 nm for LMA. Our general model explained 55.28% of LDMC variance and 55.64% of LMA variation, and the mean RMSE for the predicted values were 0.004 g g-1 and 36.99 g m-2, respectively. RF provided a consistent selection of spectral bands related to biophysical traits. This study highlighted the potential for estimation of key foliar traits from spectral information, while further efforts are necessary to disentangle the optical properties from a larger suite of vegetation types worldwide.

Length scale hierarchy and spatiotemporal change of alluvial morphologies over the Selenga River delta, Russia

NASA Astrophysics Data System (ADS)

Dong, T. Y.; Nittrouer, J.; McElroy, B. J.; Ma, H.; Czapiga, M. J.; Il'icheva, E.; Pavlov, M.; Parker, G.

2017-12-01

The movement of water and sediment in natural channels creates various types of alluvial morphologies that span length scales from dunes to deltas. The behavior of these morphologies is controlled microscopically by hydrodynamic conditions and bed material size, and macroscopically by hydrologic and geological settings. Alluvial morphologies can be modeled as either diffusive or kinematic waves, in accordance with their respective boundary conditions. Recently, it has been shown that the difference between these two dynamic behaviors of alluvial morphologies can be characterized by the backwater number, which is a dimensionless value normalizing the length scale of a morphological feature to its local hydrodynamic condition. Application of the backwater number has proven useful for evaluating the size of morphologies, including deltas (e.g., by assessing the preferential avulsion location of a lobe), and for comparing bedform types across different fluvial systems. Yet two critical questions emerge when applying the backwater number: First, how do different types of alluvial morphologies compare within a single deltaic system, where there is a hydrodynamic transition from uniform to non-uniform flow? Second, how do different types of morphologies evolve temporally within a system as a function of changing water discharge? This study addresses these questions by compiling and analyzing field data from the Selenga River delta, Russia, which include measurements of flow velocity, channel geometry, bed material grain size, and channel slope, as well as length scales of various morphologies, including dunes, island bars, meanders, bifurcations, and delta lobes. Data analyses reveal that the length scale of morphologies decrease and the backwater number increases as flow transitions from uniform to non-uniform conditions progressing downstream. It is shown that the evaluated length scale hierarchy and planform distribution of different morphologies can be used to estimate slope, shear velocity and sediment flux within this depositional system. The findings from this research can be applied to evaluate spatially and temporally varying morphodynamic conditions, based on structures measured from both modern systems and ancient sedimentary records.

Activity-dependent dendritic spine neck changes are correlated with synaptic strength

PubMed Central

Araya, Roberto; Vogels, Tim P.; Yuste, Rafael

2014-01-01

Most excitatory inputs in the mammalian brain are made on dendritic spines, rather than on dendritic shafts. Spines compartmentalize calcium, and this biochemical isolation can underlie input-specific synaptic plasticity, providing a raison d’etre for spines. However, recent results indicate that the spine can experience a membrane potential different from that in the parent dendrite, as though the spine neck electrically isolated the spine. Here we use two-photon calcium imaging of mouse neocortical pyramidal neurons to analyze the correlation between the morphologies of spines activated under minimal synaptic stimulation and the excitatory postsynaptic potentials they generate. We find that excitatory postsynaptic potential amplitudes are inversely correlated with spine neck lengths. Furthermore, a spike timing-dependent plasticity protocol, in which two-photon glutamate uncaging over a spine is paired with postsynaptic spikes, produces rapid shrinkage of the spine neck and concomitant increases in the amplitude of the evoked spine potentials. Using numerical simulations, we explore the parameter regimes for the spine neck resistance and synaptic conductance changes necessary to explain our observations. Our data, directly correlating synaptic and morphological plasticity, imply that long-necked spines have small or negligible somatic voltage contributions, but that, upon synaptic stimulation paired with postsynaptic activity, they can shorten their necks and increase synaptic efficacy, thus changing the input/output gain of pyramidal neurons. PMID:24982196

Sex differences in the regulation of spatially distinct cardiac mitochondrial subpopulations.

PubMed

Ribeiro, Rogério Faustino; Ronconi, Karoline Sousa; Morra, Elis Aguiar; Do Val Lima, Patrícia Ribeiro; Porto, Marcella Leite; Vassallo, Dalton Valentim; Figueiredo, Suely Gomes; Stefanon, Ivanita

2016-08-01

Spatially distinct mitochondrial subpopulation may mediate myocardial pathology through permeability transition pore opening (MPTP). The goal of this study was to assess sex differences on the two spatially distinct mitochondrial subpopulations: subsarcolemmal mitochondria (SSM) and intermyofibrillar mitochondria (IFM) based on morphology, membrane potential, mitochondrial function, oxidative phosphorylation, and MPTP. Aged matched Wistar rats were used to study SSM and IFM. Mitochondrial size was larger in SSM than in IFM in both genders. However, SSM internal complexity, yield, and membrane potential were higher in male than in female. The maximal rate of mitochondrial respiration, states 3 and 4, using glutamate + malate as substrate, were higher in IFM and SSM in the male group compared to female. The respiratory control ratio (RCR-state3/state 4), was not different in both SSM and IFM with glutamate + malate. The ADP:O ratio was found higher in IFM and SSM from female compared to males. When pyruvate was used, state 3 was found unchanged in both IFM and SSM, state 4 was also greater in male IFM compared to female. The RCR increased in the SSM while IFM remained the same. State 4 was higher in male SSM while in the IFM remained the same. The IFM presented a higher Ca(2+) retention capacity compared with SSM, however, there was a greater sensitivity to Ca(2+)-induced MPTP in SSM and IFM in the male group compared to female. In conclusion, our data show that spatially distinct mitochondrial subpopulations have sex-based differences in oxidative phosphorylation, morphology, and calcium retention capacity.

1,4-Naphthoquinone derivatives potently suppress Candida albicans growth, inhibit formation of hyphae and show no toxicity toward zebrafish embryos.

PubMed

Janeczko, Monika; Kubiński, Konrad; Martyna, Aleksandra; Muzyczka, Angelika; Boguszewska-Czubara, Anna; Czernik, Sławomir; Tokarska-Rodak, Małgorzata; Chwedczuk, Marta; Demchuk, Oleg M; Golczyk, Hieronim; Masłyk, Maciej

2018-04-01

In this study, we applied various assays to find new activities of 1,4-naphthoquinone derivatives for potential anti-Candida albicans applications. These assays determined (a) the antimicrobial effect on growth/cell multiplication in fungal cultures, (b) the effect on formation of hyphae and biofilm, (c) the influence on cell membrane integrity, (d) the effect on cell morphology using atomic force microscopy, and (e) toxicity against zebrafish embryos. We have demonstrated the activity of these compounds against different Candida species and clinical isolates of C. albicans. 1,4-Naphthoquinones significantly affected fungal strains at 8-250 mg l -1 of MIC. Interestingly, at concentrations below MICs, the chemicals showed effectiveness in inhibition of hyphal formation and cell aggregation in Candida. Of note, atomic force microscopy (AFM) analysis revealed an influence of the compounds on cell morphological properties. However, at low concentrations (0.8-31.2 mg l -1 ), it did not exert any evident toxic effects on zebrafish embryos. Our research has evidenced the effectiveness of 1,4-naphthoquinones as potential anti-Candida agents.

Application of X-ray micro-CT for micro-structural characterization of APCVD deposited SiC coatings on graphite conduit.

PubMed

Agrawal, A K; Sarkar, P S; Singh, B; Kashyap, Y S; Rao, P T; Sinha, A

2016-02-01

SiC coatings are commonly used as oxidation protective materials in high-temperature applications. The operational performance of the coating depends on its microstructure and uniformity. This study explores the feasibility of applying tabletop X-ray micro-CT for the micro-structural characterization of SiC coating. The coating is deposited over the internal surface of pipe structured graphite fuel tube, which is a prototype of potential components of compact high-temperature reactor (CHTR). The coating is deposited using atmospheric pressure chemical vapor deposition (APCVD) and properties such as morphology, porosity, thickness variation are evaluated. Micro-structural differences in the coating caused by substrate distance from precursor inlet in a CVD reactor are also studied. The study finds micro-CT a potential tool for characterization of SiC coating during its future course of engineering. We show that depletion of reactants at larger distances causes development of larger pores in the coating, which affects its morphology, density and thickness. Copyright © 2015 Elsevier Ltd. All rights reserved.

Supercritical phase inversion of starch-poly(epsilon-caprolactone) for tissue engineering applications.

PubMed

Duarte, Ana Rita C; Mano, João F; Reis, Rui L

2010-02-01

In this work, a starch-based polymer, namely a blend of starch-poly(epsilon-caprolactone) was processed by supercritical assisted phase inversion process. This processing technique has been proposed for the development of 3D structures with potential applications in tissue engineering applications, as scaffolds. The use of carbon dioxide as non-solvent in the phase inversion process leads to the formation of a porous and interconnected structure, dry and free of any residual solvent. Different processing conditions such as pressure (from 80 up to 150 bar) and temperature (45 and 55 degrees C) were studied and the effect on the morphological features of the scaffolds was evaluated by scanning electron microscopy and micro-computed tomography. The mechanical properties of the SPCL scaffolds prepared were also studied. Additionally, in this work, the in vitro biological performance of the scaffolds was studied. Cell adhesion and morphology, viability and proliferation was assessed and the results suggest that the materials prepared are allow cell attachment and promote cell proliferation having thus potential to be used in some for biomedical applications.

Chemical and morphological gradient scaffolds to mimic hierarchically complex tissues: From theoretical modeling to their fabrication.

PubMed

Marrella, Alessandra; Aiello, Maurizio; Quarto, Rodolfo; Scaglione, Silvia

2016-10-01

Porous multiphase scaffolds have been proposed in different tissue engineering applications because of their potential to artificially recreate the heterogeneous structure of hierarchically complex tissues. Recently, graded scaffolds have been also realized, offering a continuum at the interface among different phases for an enhanced structural stability of the scaffold. However, their internal architecture is often obtained empirically and the architectural parameters rarely predetermined. The aim of this work is to offer a theoretical model as tool for the design and fabrication of functional and structural complex graded scaffolds with predicted morphological and chemical features, to overcome the time-consuming trial and error experimental method. This developed mathematical model uses laws of motions, Stokes equations, and viscosity laws to describe the dependence between centrifugation speed and fiber/particles sedimentation velocity over time, which finally affects the fiber packing, and thus the total porosity of the 3D scaffolds. The efficacy of the theoretical model was tested by realizing engineered graded grafts for osteochondral tissue engineering applications. The procedure, based on combined centrifugation and freeze-drying technique, was applied on both polycaprolactone (PCL) and collagen-type-I (COL) to test the versatility of the entire process. A functional gradient was combined to the morphological one by adding hydroxyapatite (HA) powders, to mimic the bone mineral phase. Results show that 3D bioactive morphologically and chemically graded grafts can be properly designed and realized in agreement with the theoretical model. Biotechnol. Bioeng. 2016;113: 2286-2297. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Effects of simulated acid rain on the morphology, phenology and dry biomass of a local variety of maize (Suwan-1) in Southwestern Nigeria.

PubMed

Macaulay, Babajide Milton; Enahoro, Gloria Ebarunosen

2015-10-01

Effects of acid rain on the morphology, phenology and dry biomass of maize (Suwan-1 variety) were investigated. The maize seedlings were subjected to different pH treatments (1.0, 2.0, 3.0, 4.0, 5.0 and 6.0) of simulated acid rain (SAR) with pH 7.0 as the control for a period of 90 days. The common morphological defects due to SAR application were necrosis and chlorosis. It was observed that necrosis increased in severity as the acidity increased whilst chlorosis was dominant as the acidity decreased. SAR encouraged rapid floral and cob growth but with the consequence of poor floral and cob development in pH 1.0 to 3.0 treatments. The result for the dry biomass indicates that pH treatments 2.0 to 7.0 for total plant biomass were not significantly different (P > 0.05) from one another, but were all significantly higher (P < 0.05) than pH 1.0. Therefore, it may be deduced that Suwan-1 has the potential to withstand acid rain but with pronounced morphological and phenological defects which, however, have the capacity to reduce drastically the market value of the crop. Therefore, it may be concluded that Suwan-1 tolerated acid rain in terms of the parameters studied at pH 4.0 to 7.0 which makes it a suitable crop in acid rain-stricken climes. This research could also serve as a good reference for further SAR studies on maize or other important cereals.

Synchrotron-based transmission x-ray microscopy for improved extraction in shale during hydraulic fracturing

NASA Astrophysics Data System (ADS)

Kiss, Andrew M.; Jew, Adam D.; Joe-Wong, Claresta; Maher, Kate M.; Liu, Yijin; Brown, Gordon E.; Bargar, John

2015-09-01

Engineering topics which span a range of length and time scales present a unique challenge to researchers. Hydraulic fracturing (fracking) of oil shales is one of these challenges and provides an opportunity to use multiple research tools to thoroughly investigate a topic. Currently, the extraction efficiency from the shale is low but can be improved by carefully studying the processes at the micro- and nano-scale. Fracking fluid induces chemical changes in the shale which can have significant effects on the microstructure morphology, permeability, and chemical composition. These phenomena occur at different length and time scales which require different instrumentation to properly study. Using synchrotron-based techniques such as fluorescence tomography provide high sensitivity elemental mapping and an in situ micro-tomography system records morphological changes with time. In addition, the transmission X-ray microscope (TXM) at the Stanford Synchrotron Radiation Lightsource (SSRL) beamline 6-2 is utilized to collect a nano-scale three-dimensional representation of the sample morphology with elemental and chemical sensitivity. We present the study of a simplified model system, in which pyrite and quartz particles are mixed and exposed to oxidizing solution, to establish the basic understanding of the more complex geology-relevant oxidation reaction. The spatial distribution of the production of the oxidation reaction, ferrihydrite, is retrieved via full-field XANES tomography showing the reaction pathway. Further correlation between the high resolution TXM data and the high sensitivity micro-probe data provides insight into potential morphology changes which can decrease permeability and limit hydrocarbon recovery.

Application of a coupled smoothed particle hydrodynamics (SPH) and coarse-grained (CG) numerical modelling approach to study three-dimensional (3-D) deformations of single cells of different food-plant materials during drying.

PubMed

Rathnayaka, C M; Karunasena, H C P; Senadeera, W; Gu, Y T

2018-03-14

Numerical modelling has gained popularity in many science and engineering streams due to the economic feasibility and advanced analytical features compared to conventional experimental and theoretical models. Food drying is one of the areas where numerical modelling is increasingly applied to improve drying process performance and product quality. This investigation applies a three dimensional (3-D) Smoothed Particle Hydrodynamics (SPH) and Coarse-Grained (CG) numerical approach to predict the morphological changes of different categories of food-plant cells such as apple, grape, potato and carrot during drying. To validate the model predictions, experimental findings from in-house experimental procedures (for apple) and sources of literature (for grape, potato and carrot) have been utilised. The subsequent comaprison indicate that the model predictions demonstrate a reasonable agreement with the experimental findings, both qualitatively and quantitatively. In this numerical model, a higher computational accuracy has been maintained by limiting the consistency error below 1% for all four cell types. The proposed meshfree-based approach is well-equipped to predict the morphological changes of plant cellular structure over a wide range of moisture contents (10% to 100% dry basis). Compared to the previous 2-D meshfree-based models developed for plant cell drying, the proposed model can draw more useful insights on the morphological behaviour due to the 3-D nature of the model. In addition, the proposed computational modelling approach has a high potential to be used as a comprehensive tool in many other tissue morphology related investigations.

Morphometric of blastomeres in Salmo salar.

PubMed

Effer, Brian R; Sánchez, Rubén R; Ubilla, Andrea M; Figueroa, Elías V; Valdebenito, Iván I

2014-11-01

For Salmo salar, there is a lack of information on the morphology of the first blastomeres formed during embryonic development and which could be used as a diagnostic tool for the first stages of development. The purpose of this investigation, therefore, was to characterize morphometrically the first blastomeres of S. salar. From a pool of eggs incubated at 7.5°C, 100 microphotographs of blastodiscs were extracted and analyzed at different incubation periods: 12, 14, 16, 20 or 24 h. Blastodiscs were characterized morphologically after 16, 20 or 24 h incubation, and classified into symmetric or asymmetric groups according to their morphology. The ratio of length (L) versus width (W) of each blastomere was determined, to establish its symmetry. In addition, 20 microphotographs of blastodiscs of normal appearance were analysed morphologically (control blastodisc: CB) for comparison (20 or 24 h). Results show that the first cleavage ends after 16 h of development. Seven categories were established during blastomere characterization: 47% normal (G1); 27% with dispersed margins (G2); 10% unequal (G3); 9% 'pie-shaped' (G4); 3% amorphous (G5); 2% three equal blastomeres and one different one (G6); and 2% with eccentric cleavage (G7). Although the incidence of abnormal cleavage in S. salar is uncertain, there is a potential for some asymmetries to be corrected during embryogenesis to generate viable individuals. More studies are necessary to correlate these abnormal cleavage patterns with indicators of quality in the later stages of embryogenesis in this species, to establish a quality assessment tool for gametes and/or embryos in salmonid species.

The delayed rectifier, IKI, is the major conductance in type I vestibular hair cells across vestibular end organs

NASA Technical Reports Server (NTRS)

Ricci, A. J.; Rennie, K. J.; Correia, M. J.

1996-01-01

Hair cells were dissociated from the semicircular canal, utricle, lagena and saccule of white king pigeons. Type I hair cells were identified morphologically based on the ratios of neck width to cuticular plate width (NPR < 0.72) as well as neck width to cell body width (NBR < 0.64). The perforated patch variant of the whole-cell recording technique was used to measure electrical properties from type I hair cells. In voltage-clamp, the membrane properties of all identified type I cells were dominated by a predominantly outward potassium current, previously characterized in semicircular canal as IKI. Zero-current potential, activation, deactivation, slope conductance, pharmacologic and steady-state properties of the complex currents were not statistically different between type I hair cells of different vestibular end organs. The voltage dependence causes a significant proportion of this conductance to be active about the cell's zero-current potential. The first report of the whole-cell activation kinetics of the conductance is presented, showing a voltage dependence that could be best fit by an equation for a single exponential. Results presented here are the first data from pigeon dissociated type I hair cells from utricle, saccule and lagena suggesting that the basolateral conductances of a morphologically identified population of type I hair cells are conserved between functionally different vestibular end organs; the major conductance being a delayed rectifier characterized previously in semicircular canal hair cells as IKI.

Altered apolipoprotein C expression in association with cognition impairments and hippocampus volume in schizophrenia and bipolar disorder.

PubMed

Knöchel, Christian; Kniep, Jonathan; Cooper, Jason D; Stäblein, Michael; Wenzler, Sofia; Sarlon, Jan; Prvulovic, David; Linden, David E J; Bahn, Sabine; Stocki, Pawel; Ozcan, Sureyya; Alves, Gilberto; Carvalho, Andre F; Reif, Andreas; Oertel-Knöchel, Viola

2017-04-01

Proteomic analyses facilitate the interpretation of molecular biomarker probes which are very helpful in diagnosing schizophrenia (SZ). In the current study, we attempt to test whether potential differences in plasma protein expressions in SZ and bipolar disorder (BD) are associated with cognitive deficits and their underlying brain structures. Forty-two plasma proteins of 29 SZ patients, 25 BD patients and 93 non-clinical controls were quantified and analysed using multiple reaction monitoring-based triple quadrupole mass spectrometry approach. We also computed group comparisons of protein expressions between patients and controls, and between SZ and BD patients, as well. Potential associations of protein levels with cognitive functioning (psychomotor speed, executive functioning, crystallised intelligence) as well as underlying brain volume in the hippocampus were explored, using bivariate correlation analyses. The main finding of this study was that apolipoprotein expression differed between patients and controls and that these alterations in both disease groups were putatively related to cognitive impairments as well as to hippocampus volumes. However, none of the protein level differences were related to clinical symptom severity. In summary, altered apolipoprotein expression in BD and SZ was linked to cognitive decline and underlying morphological changes in both disorders. Our results suggest that the detection of molecular patterns in association with cognitive performance and its underlying brain morphology is of great importance for understanding of the pathological mechanisms of SZ and BD, as well as for supporting the diagnosis and treatment of both disorders.

A morphological comparison of narrow, low-gradient streams traversing wetland environments to alluvial streams.

PubMed

Jurmu, Michael C

2002-12-01

Twelve morphological features from research on alluvial streams are compared in four narrow, low-gradient wetland streams located in different geographic regions (Connecticut, Indiana, and Wisconsin, USA). All four reaches differed in morphological characteristics in five of the features compared (consistent bend width, bend cross-sectional shape, riffle width compared to pool width, greatest width directly downstream of riffles, and thalweg location), while three reaches differed in two comparisons (mean radius of curvature to width ratio and axial wavelength to width ratio). The remaining five features compared had at least one reach where different characteristics existed. This indicates the possibility of varying morphology for streams traversing wetland areas further supporting the concept that the unique qualities of wetland environments might also influence the controls on fluvial dynamics and the development of streams. If certain morphological features found in streams traversing wetland areas differ from current fluvial principles, then these varying features should be incorporated into future wetland stream design and creation projects. The results warrant further research on other streams traversing wetlands to determine if streams in these environments contain unique morphology and further investigation of the impact of low-energy fluvial processes on morphological development. Possible explanations for the morphology deviations in the study streams and some suggestions for stream design in wetland areas based upon the results and field observations are also presented.

Rapid genetic diversification within dog breeds as evidenced by a case study on Schnauzers.

PubMed

Streitberger, K; Schweizer, M; Kropatsch, R; Dekomien, G; Distl, O; Fischer, M S; Epplen, J T; Hertwig, S T

2012-10-01

As a result of strong artificial selection, the domesticated dog has arguably become one of the most morphologically diverse vertebrate species, which is mirrored in the classification of around 400 different breeds. To test the influence of breeding history on the genetic structure and variability of today's dog breeds, we investigated 12 dog breeds using a set of 19 microsatellite markers from a total of 597 individuals with about 50 individuals analysed per breed. High genetic diversity was noted over all breeds, with the ancient Asian breeds (Akita, Chow Chow, Shar Pei) exhibiting the highest variability, as was indicated chiefly by an extraordinarily high number of rare and private alleles. Using a Bayesian clustering method, we detected significant genetic stratification within the closely related Schnauzer breeds. The individuals of these three recently differentiated breeds (Miniature, Standard and Giant Schnauzer) could not be assigned to a single cluster each. This hidden genetic structure was probably caused by assortative mating owing to breeders' preferences regarding coat colour types and the underlying practice of breeding in separate lineages. Such processes of strong artificial disruptive selection for different morphological traits in isolated and relatively small lineages can result in the rapid creation of new dog types and potentially new breeds and represent a unique opportunity to study the evolution of genetic and morphological differences in recently diverged populations. © 2011 The Authors, Animal Genetics © 2011 Stichting International Foundation for Animal Genetics.

Facile synthesis of hierarchical mesoporous weirds-like morphological MnO2 thin films on carbon cloth for high performance supercapacitor application.

PubMed

Shinde, Pragati A; Lokhande, Vaibhav C; Ji, Taeksoo; Lokhande, Chandrakant D

2017-07-15

The mesoporous nanostructured metal oxides have a lot of capabilities to upsurge the energy storing capacity of the supercapacitor. In present work, different nanostructured morphologies of MnO 2 have been successfully fabricated on flexible carbon cloth by simple but capable hydrothermal method at different deposition temperatures. The deposition temperature has strong influence on reaction kinetics, which subsequently alters the morphology and electrochemical performance. Among different nanostructured MnO 2 thin films, the mesoporous weirds composed thin film obtained at temperature of 453K exhibits excellent physical and electrochemical features for supercapacitor application. The weirds composed MnO 2 thin film exhibits specific surface area of 109m 2 g -1 , high specific capacitance of 595Fg -1 with areal capacitance of 4.16Fcm -2 at a scan rate of 5mVs -1 and high specific energy of 56.32Whkg -1 . In addition to this, MnO 2 weirds attain capacity retention of 87 % over 2000 CV cycles, representing better cycling stability. The enhanced electrochemical performance could be ascribed to direct growth of highly porous MnO 2 weirds on carbon cloth which provide more pathways for easy diffusion of electrolyte into the interior of electroactive material. The as-fabricated electrode with improved performance could be ascribed as a potential electrode material for energy storage devices. Copyright © 2017 Elsevier Inc. All rights reserved.

Shape matters: The case for Ellipsoids and Ellipsoidal Water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tillack, Andreas F.; Robinson, Bruce H.

We describe the shape potentials used for the van der Waals interactions between soft-ellipsoids used to coarse-grain molecular moieties in our Metropolis Monte-Carlo simulation software. The morphologies resulting from different expressions for these van der Waals interaction potentials are discussed for the case of a prolate spheroid system with a strong dipole at the ellipsoid center. We also show that the calculation of ellipsoids is, at worst, only about fivefold more expensive computationally when compared to a simple Lennard- Jones sphere. Finally, as an application of the ellipsoidal shape we parametrize water from the original SPC water model and observemore » – just through the difference in shape alone – a significant improvement of the O-O radial distribution function when compared to experimental data.« less

Gravimetric humidity sensor based on ZnO nanorods covered piezoresistive Si microcantilever

NASA Astrophysics Data System (ADS)

Xu, Jiushuai; Bertke, Maik; Li, Xiaojing; Gad, Alaaeldin; Zhou, Hao; Wasisto, Hutomo Suryo; Peiner, Erwin

2017-06-01

A ZnO nanorods film covered silicon resonant cantilever sensor is developed for atmosphere humidity detection by monitoring the resonant frequency shifts induced by the additional weight of adsorbed water molecules. Two different crystalline seed-layer deposition methods were applied to grow different nanorods films. The morphology of the ZnO films were characterized and the sensor sensitivities were measured under different relative humidity (RH) levels. The experiments results showed that this novel humidity sensor with ZnO nanorods has a sensitivity of 101.5 +/- 12.0 ppm/RH% (amount of adsorbed water of 36.9 +/- 4.4 ng/RH%), indicating its potential for portable sensing applications.

Fe-tannic acid complex dye as photo sensitizer for different morphological ZnO based DSSCs

NASA Astrophysics Data System (ADS)

Çakar, Soner; Özacar, Mahmut

2016-06-01

In this paper we have synthesized different morphological ZnO nanostructures via microwave hydrothermal methods at low temperature within a short time. We described different morphologies of ZnO at different Zn(NO3)2/KOH mole ratio. The ZnO nanostructures were characterized via X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and UV-vis spectrophotometry. All ZnO structures have hexagonal wurtzite type structures. The FESEM images showed various morphologies of ZnO such as plate, rod and nanoparticles. Dye sensitized solar cells have been assembled by these different morphological structures photo electrode and tannic acid or Fe-tannic acid complex dye as sensitizer. We have achieved at maximum efficiencies of photovoltaic cells prepared with ZnO plate in all dye systems. The conversion efficiencies of dye sensitized solar cells are 0.37% and 1.00% with tannic acid and Fe-tannic acid complex dye, respectively.

CT Examination of Nose and Paranasal Sinuses of Egyptian Mummies and Three Distinct Human Population Groups: Anthropological and Clinical Implications.

PubMed

Márquez, Samuel; Lawson, William; Mowbray, Kenneth; Delman, Bradley N; Laitman, Jeffrey T

2015-06-01

The interaction of nasal morphology and climatic conditions has resulted in diverse hard- and soft-tissue configurations across human population groups. While the processes of skull pneumatization are not fully understood, the invasions of the paranasal sinuses [PNS] into the cranium have contributed to assorted morphologies. Human migratory patterns and the strong association with climatic variables through time and space may explain this diversity. This study examined four multiregional populations of which two are from Egypt but of widely divergent eras. Three Egyptian mummies [EG-M] from the middle kingdom were CT scanned providing a unique opportunity to investigate the status of PNS anatomy within a time frame from 1567 BCE to 600 CE and compare it to a contemporary Egyptian [EG] (n = 12) population. Dry skulls of Inuit [IT] (n = 10) and East African [EA] (n = 8) provide out-group comparisons, as one group represents an isolated geographic environment far different from that of Egypt and the other group inhabiting distinct environmental conditions albeit located within the same continent. Results showed EG-M and EG frontal sinus volumes were diminutive in size with no statistically significant difference between them. Maxillary sinus size values of EG-M and EG clustered together while IT and EA significantly differed from each other (P = 0.002). The multiregional groups exhibited population specific morphologies in their PNS anatomy. Ecogeographic localities revealed anatomical differences among IT and EA, while the potential time span of about 3,500 years produced only a negligible difference between the Egyptian groups. The small sample sizes incorporated into this research requires confirmation of the results by analyses of larger samples from each geographic region and with the integration of a larger group of Egyptian mummified remains. © 2015 Wiley Periodicals, Inc.

Are lianas more drought-tolerant than trees? A test for the role of hydraulic architecture and other stem and leaf traits.

PubMed

van der Sande, Masha T; Poorter, Lourens; Schnitzer, Stefan A; Markesteijn, Lars

2013-08-01

Lianas are an important component of neotropical forests, where evidence suggests that they are increasing in abundance and biomass. Lianas are especially abundant in seasonally dry tropical forests, and as such it has been hypothesized that they are better adapted to drought, or that they are at an advantage under the higher light conditions in these forests. However, the physiological and morphological characteristics that allow lianas to capitalize more on seasonal forest conditions compared to trees are poorly understood. Here, we evaluate how saplings of 21 tree and liana species from a seasonal tropical forest in Panama differ in cavitation resistance (P50) and maximum hydraulic conductivity (K(h)), and how saplings of 24 tree and liana species differ in four photosynthetic leaf traits (e.g., maximum assimilation and stomatal conductance) and six morphological leaf and stem traits (e.g., wood density, maximum vessel length, and specific leaf area). At the sapling stage, lianas had a lower cavitation resistance than trees, implying lower drought tolerance, and they tended to have a higher potential hydraulic conductivity. In contrast to studies focusing on adult trees and lianas, we found no clear differences in morphological and photosynthetic traits between the life forms. Possibly, lianas and trees are functionally different at later ontogenetic stages, with lianas having deeper root systems than trees, or experience their main growth advantage during wet periods, when they are less vulnerable to cavitation and can achieve high conductivity. This study shows, however, that the hydraulic characteristics and functional traits that we examined do not explain differences in liana and tree distributions in seasonal forests.

Chemical Characterization and Determination of the Anti-Oxidant Capacity of Two Brown Algae with Respect to Sampling Season and Morphological Structures Using Infrared Spectroscopy and Multivariate Analyses.

PubMed

Beratto, Angelo; Agurto, Cristian; Freer, Juanita; Peña-Farfal, Carlos; Troncoso, Nicolás; Agurto, Andrés; Castillo, Rosario Del P

2017-10-01

Brown algae biomass has been shown to be a highly important industrial source for the production of alginates and different nutraceutical products. The characterization of this biomass is necessary in order to allocate its use to specific applications according to the chemical and biological characteristics of this highly variable resource. The methods commonly used for algae characterization require a long time for the analysis and rigorous pretreatments of samples. In this work, nondestructive and fast analyses of different morphological structures from Lessonia spicata and Macrocystis pyrifera, which were collected during different seasons, were performed using Fourier transform infrared (FT-IR) techniques in combination with chemometric methods. Mid-infrared (IR) and near-infrared (NIR) spectral ranges were tested to evaluate the spectral differences between the species, seasons, and morphological structures of algae using a principal component analysis (PCA). Quantitative analyses of the polyphenol and alginate contents and the anti-oxidant capacity of the samples were performed using partial least squares (PLS) with both spectral ranges in order to build a predictive model for the rapid quantification of these parameters with industrial purposes. The PCA mainly showed differences in the samples based on seasonal sampling, where changes were observed in the bands corresponding to polysaccharides, proteins, and lipids. The obtained PLS models had high correlation coefficients (r) for the polyphenol content and anti-oxidant capacity (r > 0.9) and lower values for the alginate determination (0.7 < r < 0.8). Fourier transform infrared-based techniques were suitable tools for the rapid characterization of algae biomass, in which high variability in the samples was incorporated for the qualitative and quantitative analyses, and have the potential to be used on an industrial scale.

Vision in the common bed bug Cimex lectularius L. (Hemiptera: Cimicidae): eye morphology and spectral sensitivity.

PubMed

McNeill, C A; Allan, S A; Koehler, P G; Pereira, R M; Weeks, E N I

2016-12-01

Bed bugs as pests of public health importance recently experienced a resurgence in populations throughout the U.S. and other countries. Consequently, recent research efforts have focused on improving understanding of bed bug physiology and behaviour to improve management. While few studies have investigated the visual capabilities of bed bugs, the present study focused specifically on eye morphology and spectral sensitivity. A 3-D imaging technique was used to document bed bug eye morphology from the first instar through adult and revealed morphological characteristics that differentiate the common bed bug from the tropical bed bug as well as sex-specific differences. Electrophysiological measurements were used to evaluate the spectral sensitivity of adult bed bugs. Male bed bugs were more responsive than females at some wavelengths. Electrophysiological studies provided evidence for at least one photoreceptor with a spectral sensitivity curve peak in the green (λ max 520 nm) region of the spectrum. The broadened long wavelength portion of the spectral sensitivity curve may potentially indicate another photoreceptor in the yellow-green (λ max 550 nm) portion of the spectrum or screening pigments. Understanding more about bed bug visual biology is vital for designing traps, which are an important component of integrated bed bug management. © 2016 The Royal Entomological Society.

Morphologic study of the effect of iron on pseudocyst formation in Trichomonas vaginalis and its interaction with human epithelial cells.

PubMed

Dias-Lopes, Geovane; Saboia-Vahia, Leonardo; Margotti, Eliane Trindade; Fernandes, Nilma de Souza; Castro, Cássia Luana de Faria; Oliveira, Francisco Odencio; Peixoto, Juliana Figueiredo; Britto, Constança; Silva, Fernando Costa E; Cuervo, Patricia; Jesus, José Batista de

2017-10-01

Trichomonas vaginalis is the aetiological agent of human trichomoniasis, which is one of the most prevalent sexually transmitted diseases in humans. Iron is an important element for the survival of this parasite and the colonisation of the host urogenital tract. In this study, we investigated the effects of iron on parasite proliferation in the dynamics of pseudocyst formation and morphologically characterised iron depletion-induced pseudocysts. We performed structural and ultrastructural analyses using light microscopy, scanning electron microscopy and transmission electron microscopy. It was observed that iron depletion (i) interrupts the proliferation of T. vaginalis, (ii) induces morphological changes in typical multiplicative trophozoites to spherical non-proliferative, non-motile pseudocysts, and (iii) induces the arrest of cell division at different stages of the cell cycle; (iv) iron is the fundamental element for the maintenance of typical trophozoite morphology; (v) pseudocysts induced by iron depletion are viable and reversible forms; and, finally, (vi) we demonstrated that pseudocysts induced by iron depletion are able to interact with human epithelial cells maintaining their spherical forms. Together, these data suggest that pseudocysts could be induced as a response to iron nutritional stress and could have a potential role in the transmission and infection of T. vaginalis.

Computational Examination of Orientation-Dependent Morphological Evolution during the Electrodeposition and Electrodissolution of Magnesium

DOE PAGES

DeWitt, S.; Hahn, N.; Zavadil, K.; ...

2015-12-30

Here a new model of electrodeposition and electrodissolution is developed and applied to the evolution of Mg deposits during anode cycling. The model captures Butler-Volmer kinetics, facet evolution, the spatially varying potential in the electrolyte, and the time-dependent electrolyte concentration. The model utilizes a diffuse interface approach, employing the phase field and smoothed boundary methods. Scanning electron microscope (SEM) images of magnesium deposited on a gold substrate show the formation of faceted deposits, often in the form of hexagonal prisms. Orientation-dependent reaction rate coefficients were parameterized using the experimental SEM images. Three-dimensional simulations of the growth of magnesium deposits yieldmore » deposit morphologies consistent with the experimental results. The simulations predict that the deposits become narrower and taller as the current density increases due to the depletion of the electrolyte concentration near the sides of the deposits. Increasing the distance between the deposits leads to increased depletion of the electrolyte surrounding the deposit. Two models relating the orientation-dependence of the deposition and dissolution reactions are presented. Finally, the morphology of the Mg deposit after one deposition-dissolution cycle is significantly different between the two orientation-dependence models, providing testable predictions that suggest the underlying physical mechanisms governing morphology evolution during deposition and dissolution.« less

Effect of Cymbopogon citratus (lemongrass) and Syzygium aromaticum (clove) oils on the morphology and mortality of Aedes aegypti and Anopheles dirus larvae.

PubMed

Soonwera, Mayura; Phasomkusolsil, Siriporn

2016-04-01

Cymbopogon citratus (lemongrass) and Syzygium aromaticum (clove) oils were evaluated to determine mortality rates, morphological aberrations, and persistence when used against third and fourth larval instars of Aedes aegypti and Anopheles dirus. The oils were evaluated at 1, 5, and 10 % concentrations in mixtures with soybean oil. Persistence of higher concentrations was measured over a period of 10 days. For Ae. aegypti, both plant oils caused various morphological aberrations to include deformed larvae, incomplete eclosion, white pupae, deformed pupae, dead normal pupae, and incomplete pupal eclosion. All of these aberrations led to larval mortality. In Ae. aegypti larvae, there were no significant differences in mortality at days 1, 5, and 10 or between third and fourth larval instar exposure. In An. dirus, morphological aberrations were rare and S. aromaticum oil was more effective in causing mortality among all larval stages. Both oils were equally effective at producing mortality on days 1, 5, and 10. Both oils had slightly increased LT50 rates from day 1 to day 10. In conclusion, both lemongrass and clove oils have significant effects on the immature stages of Ae. aegypti and An. dirus and could potentially be developed for use as larvicides.

Morphological and functional evaluation of chronic pancreatitis with magnetic resonance imaging

PubMed Central

Hansen, Tine Maria; Nilsson, Matias; Gram, Mikkel; Frøkjær, Jens Brøndum

2013-01-01

Magnetic resonance imaging (MRI) techniques for assessment of morphology and function of the pancreas have been improved dramatically the recent years and MRI is very often used in diagnosing and follow-up of chronic pancreatitis (CP) patients. Standard MRI including fat-suppressed T1-weighted and T2-weighted imaging techniques reveal decreased signal and glandular atrophy of the pancreas in CP. In contrast-enhanced MRI of the pancreas in CP the pancreatic signal is usually reduced and delayed due to decreased perfusion as a result of chronic inflammation and fibrosis. Thus, morphological changes of the ductal system can be assessed by magnetic resonance cholangiopancreatography (MRCP). Furthermore, secretin-stimulated MRCP is a valuable technique to evaluate side branch pathology and the exocrine function of the pancreas and diffusion weighted imaging can be used to quantify both parenchymal fibrotic changes and the exocrine function of the pancreas. These standard and advanced MRI techniques are supplementary techniques to reveal morphological and functional changes of the pancreas in CP. Recently, spectroscopy has been used for assessment of metabolite concentrations in-vivo in different tissues and may have the potential to offer better tissue characterization of the pancreas. Hence, the purpose of the present review is to provide an update on standard and advanced MRI techniques of the pancreas in CP. PMID:24259954

Morphologic study of the effect of iron on pseudocyst formation in Trichomonas vaginalis and its interaction with human epithelial cells

PubMed Central

Dias-Lopes, Geovane; Saboia-Vahia, Leonardo; Margotti, Eliane Trindade; Fernandes, Nilma de Souza; Castro, Cássia Luana de Faria; Oliveira, Francisco Odencio; Peixoto, Juliana Figueiredo; Britto, Constança; Silva, Fernando Costa e; Cuervo, Patricia; de Jesus, José Batista

2017-01-01

BACKGROUND Trichomonas vaginalis is the aetiological agent of human trichomoniasis, which is one of the most prevalent sexually transmitted diseases in humans. Iron is an important element for the survival of this parasite and the colonisation of the host urogenital tract. OBJECTIVES In this study, we investigated the effects of iron on parasite proliferation in the dynamics of pseudocyst formation and morphologically characterised iron depletion-induced pseudocysts. METHODS We performed structural and ultrastructural analyses using light microscopy, scanning electron microscopy and transmission electron microscopy. FINDINGS It was observed that iron depletion (i) interrupts the proliferation of T. vaginalis, (ii) induces morphological changes in typical multiplicative trophozoites to spherical non-proliferative, non-motile pseudocysts, and (iii) induces the arrest of cell division at different stages of the cell cycle; (iv) iron is the fundamental element for the maintenance of typical trophozoite morphology; (v) pseudocysts induced by iron depletion are viable and reversible forms; and, finally, (vi) we demonstrated that pseudocysts induced by iron depletion are able to interact with human epithelial cells maintaining their spherical forms. MAIN CONCLUSIONS Together, these data suggest that pseudocysts could be induced as a response to iron nutritional stress and could have a potential role in the transmission and infection of T. vaginalis. PMID:28953994

Geomatics for Mapping of Groundwater Potential Zones in Northern Part of the United Arab Emiratis - Sharjah City

NASA Astrophysics Data System (ADS)

Al-Ruzouq, R.; Shanableh, A.; Merabtene, T.

2015-04-01

In United Arab Emirates (UAE) domestic water consumption has increased rapidly over the last decade. The increased demand for high-quality water, create an urgent need to evaluate the groundwater production of aquifers. The development of a reasonable model for groundwater potential is therefore crucial for future systematic developments, efficient management, and sustainable use of groundwater resources. The objective of this study is to map the groundwater potential zones in northern part of UAE and assess the contributing factors for exploration of potential groundwater resources. Remote sensing data and geographic information system will be used to locate potential zones for groundwater. Various maps (i.e., base, soil, geological, Hydro-geological, Geomorphologic Map, structural, drainage, slope, land use/land cover and average annual rainfall map) will be prepared based on geospatial techniques. The groundwater availability of the basin will qualitatively classified into different classes based on its hydro-geo-morphological conditions. The land use/land cover map will be also prepared for the different seasons using a digital classification technique with a ground truth based on field investigation.

Associations between male infertility and ancestry in South Americans: a case control study.

PubMed

Skowronek, Maria Fernanda; Velazquez, Tatiana; Mut, Patricia; Figueiro, Gonzalo; Sans, Monica; Bertoni, Bernardo; Sapiro, Rossana

2017-07-26

Infertility affects 15% of human couples, with men being responsible in approximately 50% of cases. Moreover, the aetiology of male factor infertility is poorly understood. The majority of male factor infertility remains idiopathic and potentially genetic in origin. The association of the Y chromosome and mitochondrial haplogroups with male infertility has been previously reported. This association differs between studied populations and their geographical distributions. These effects have been only rarely analysed in mixed populations, such as South Americans. In this study, we analysed the contributions of the Y chromosome and mitochondrial haplogroups to male infertility in a mixed population. A case control study was conducted. Regular PCR and high-resolutionmelting- real-time PCR were performed to type haplogroups from fertile and infertile men. The sperm parameters from infertile men were compared in each haplogroup by logistic regression analysis and ANOVA. The genotyping confirmed the known admixture characteristic of the Uruguayan population. The European paternal contribution was higher than the maternal contribution in both fertile and infertile men. Neither maternal nor paternal ancestry presented differences between the cases and controls. Men belonging to the Y chromosome haplogroup F(xK) more frequently presented with an abnormal sperm morphology than men from other haplogroups. The sperm parameters were not associated with the mitochondrial haplogroups. The data presented in this study showed an association between male infertility and ancestry in the Uruguayan population. Specifically, abnormal sperm morphology was associated with the Y chromosome haplogroup F(xK). Since the Y chromosome lacks recombination, these data suggest that some genes that determine sperm morphology might be inherited in blocks with the region that determines specific haplogroups. However, the possible association between the Y chromosome haplogroup F(xK) and sperm morphology requires further confirmatory testing. Data linking infertility with ancestry are needed to establish the possible causes of infertility and define male populations susceptible to infertility. Whether the admixed characteristics of the Uruguayan population exert any pressure on male fertility potential must be further investigated.

Survival potential of wild type cellulose deficient Salmonella from the feed industry.

PubMed

Vestby, Lene K; Møretrø, Trond; Ballance, Simon; Langsrud, Solveig; Nesse, Live L

2009-11-23

Biofilm has been shown to be one way for Salmonella to persist in the feed factory environment. Matrix components, such as fimbriae and cellulose, have been suggested to play an important role in the survival of Salmonella in the environment. Multicellular behaviour by Salmonella is often categorized according to colony morphology into rdar (red, dry and rough) expressing curli fimbriae and cellulose, bdar (brown, dry and rough) expressing curli fimbriae and pdar (pink, dry and rough) expressing cellulose. The aim of the study was to look into the distribution of morphotypes among feed and fish meal factory strains of Salmonella, with emphasis on potential differences between morphotypes with regards to survival in the feed factory environment. When screening a total of 148 Salmonella ser. Agona, Salmonella ser. Montevideo, Salmonella ser. Senftenberg and Salmonella ser. Typhimurium strains of feed factory, human clinical and reference collection origin, as many as 99% were able to express rough morphology (rdar or bdar). The dominant morphotype was rdar (74%), however as many as 55% of Salmonella ser. Agona and 19% of Salmonella ser. Senftenberg displayed the bdar morphology. Inconsistency in Calcofluor binding, indicating expression of cellulose, was found among 25% of all the strains tested, however Salmonella ser. Agona showed to be highly consistent in Calcofluor binding (98%). In biofilm, Salmonella ser. Agona strains with bdar mophology was found to be equally tolerant to disinfection treatment as strains with rdar morphotype. However, rdar morphology appeared to be favourable in long term survival in biofilm in a very dry environment. Chemical analysis showed no major differences in polysaccharide content between bdar and rdar strains. Our results indicate that cellulose is not a major component of the Salmonella biofilm matrix. The bdar morphotype is common among Salmonella ser. Agona strains isolated from the factory environment. The rdar and the bdar strains were found to be equally tolerant to disinfectants, while the rdar strain was found to be more tolerant to long-term desiccation and nutrient depletion in biofilm than the bdar strain. Cellulose does not appear to be a major component of the Salmonella biofilm matrix.

Plant Survival and Mortality during Drought Can be Mediated by Co-occurring Species' Physiological and Morphological Traits: Results from a Model

NASA Astrophysics Data System (ADS)

Tai, X.; Mackay, D. S.

2015-12-01

Interactions among co-occurring species are mediated by plant physiology, morphology and environment. Without proper mechanisms to account for these factors, it remains difficult to predict plant mortality/survival under changing climate. A plant ecophysiological model, TREES, was extended to incorporate co-occurring species' belowground interaction for water. We used it to examine the interaction between two commonly co-occurring species during drought experiment, pine (Pinus edulis) and juniper (Juniperus monosperma), with contrasting physiological traits (vulnerability to cavitation and leaf water potential regulation). TREES was parameterized and validated using field-measured plant physiological traits. The root architecture (depth, profile, and root area to leaf area ratio) of juniper was adjusted to see how root morphology could affect the survival/mortality of its neighboring pine under both ambient and drought conditions. Drought suppressed plant water and carbon uptake, as well increased the average percentage loss of conductivity (PLC). Pine had 59% reduction in water uptake, 48% reduction in carbon uptake, and 38% increase in PLC, while juniper had 56% reduction in water uptake, 50% reduction in carbon and 29% increase in PLC, suggesting different vulnerability to drought as mediated by plant physiological traits. Variations in juniper root architecture further mediated drought stress on pine, from negative to positive. Different juniper root architecture caused variations in response of pine over drought (water uptake reduction ranged 0% ~63%, carbon uptake reduction ranged 0% ~ 70%, and PLC increase ranged 2% ~ 91%). Deeper or more uniformly distributed roots of juniper could effectively mitigate stress experienced by pine. In addition, the total water and carbon uptake tended to increase as the ratio of root area to leaf area increased while PLC showed non-monotonic response, suggesting the potential trade-off between maximizing resource uptake and susceptibility to cavitation. The results showed that co-occurring species' morphological traits could alleviate or aggravate stress imposed by drought and should therefore be considered together with plant physiological traits in predicting plant mortality and ecosystem structural shift under future climate conditions.

Morphological, molecular and functional differences of adult bone marrow- and adipose-derived stem cells isolated from rats of different ages

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mantovani, Cristina; Department of Integrative Medical Biology and Surgical and Perioperative Science, Umea University, Umea; Department of Surgical and Perioperative Science, Umea University, Umea

2012-10-01

Adult mesenchymal stem cells have self-renewal and multiple differentiation potentials, and play important roles in regenerative medicine. However, their use may be limited by senescence or age of the donor, leading to changes in stem cell functionality. We investigated morphological, molecular and functional differences between bone marrow-derived (MSC) and adipose-derived (ASC) stem cells isolated from neonatal, young and old rats compared to Schwann cells from the same animals. Immunocytochemistry, RT-PCR, proliferation assays, western blotting and transmission electron microscopy were used to investigate expression of senescence markers. Undifferentiated and differentiated ASC and MSC from animals of different ages expressed Notch-2 atmore » similar levels; protein-38 and protein-53 were present in all groups of cells with a trend towards increased levels in cells from older animals compared to those from neonatal and young rats. Following co-culture with adult neuronal cells, dMSC and dASC from animals of all ages elicited robust neurite outgrowth. Mitotracker{sup Registered-Sign} staining was consistent with ultrastructural changes seen in the mitochondria of cells from old rats, indicative of senescence. In conclusion, this study showed that although the cells from aged animals expressed markers of senescence, aged MSC and ASC differentiated into SC-like cells still retain potential to support axon regeneration. -- Highlights: Black-Right-Pointing-Pointer Aged MSC and ASC differentiated into Schwann-like cells support axon regeneration. Black-Right-Pointing-Pointer p53 expression does not appreciably influence the biology of Schwann or stem cells. Black-Right-Pointing-Pointer Notch 2 expression was similar in cells derived from animals of different ages. Black-Right-Pointing-Pointer Proliferation rates of dMSC varied little over time or with animal age.« less

Estimating abundances of interacting species using morphological traits, foraging guilds, and habitat

USGS Publications Warehouse

Dorazio, Robert M.; Connor, Edward F.

2014-01-01

We developed a statistical model to estimate the abundances of potentially interacting species encountered while conducting point-count surveys at a set of ecologically relevant locations - as in a metacommunity of species. In the model we assume that abundances of species with similar traits (e.g., body size) are potentially correlated and that these correlations, when present, may exist among all species or only among functionally related species (such as members of the same foraging guild). We also assume that species-specific abundances vary among locations owing to systematic and stochastic sources of heterogeneity. For example, if abundances differ among locations due to differences in habitat, then measures of habitat may be included in the model as covariates. Naturally, the quantitative effects of these covariates are assumed to differ among species. Our model also accounts for the effects of detectability on the observed counts of each species. This aspect of the model is especially important for rare or uncommon species that may be difficult to detect in community-level surveys. Estimating the detectability of each species requires sampling locations to be surveyed repeatedly using different observers or different visits of a single observer. As an illustration, we fitted models to species-specific counts of birds obtained while sampling an avian community during the breeding season. In the analysis we examined whether species abundances appeared to be correlated due to similarities in morphological measures (body mass, beak length, tarsus length, wing length, tail length) and whether these correlations existed among all species or only among species of the same foraging guild. We also used the model to estimate the effects of forested area on species abundances and the effects of sound power output (as measured by body size) on species detection probabilities.

THE PARADOX OF SIGN LANGUAGE MORPHOLOGY

PubMed Central

Aronoff, Mark; Meir, Irit; Sandler, Wendy

2011-01-01

Sign languages have two strikingly different kinds of morphological structure: sequential and simultaneous. The simultaneous morphology of two unrelated sign languages, American and Israeli Sign Language, is very similar and is largely inflectional, while what little sequential morphology we have found differs significantly and is derivational. We show that at least two pervasive types of inflectional morphology, verb agreement and classifier constructions, are iconically grounded in spatiotemporal cognition, while the sequential patterns can be traced to normal historical development. We attribute the paucity of sequential morphology in sign languages to their youth. This research both brings sign languages much closer to spoken languages in their morphological structure and shows how the medium of communication contributes to the structure of languages.* PMID:22223926

3D-printing of undisturbed soil imaged by X-ray

NASA Astrophysics Data System (ADS)

Bacher, Matthias; Koestel, John; Schwen, Andreas

2014-05-01

The unique pore structures in Soils are altered easily by water flow. Each sample has a different morphology and the results of repetitions vary as well. Soil macropores in 3D-printed durable material avoid erosion and have a known morphology. Therefore potential and limitations of reproducing an undisturbed soil sample by 3D-printing was evaluated. We scanned an undisturbed soil column of Ultuna clay soil with a diameter of 7 cm by micro X-ray computer tomography at a resolution of 51 micron. A subsample cube of 2.03 cm length with connected macropores was cut out from this 3D-image and printed in five different materials by a 3D-printing service provider. The materials were ABS, Alumide, High Detail Resin, Polyamide and Prime Grey. The five print-outs of the subsample were tested on their hydraulic conductivity by using the falling head method. The hydrophobicity was tested by an adapted sessile drop method. To determine the morphology of the print-outs and compare it to the real soil also the print-outs were scanned by X-ray. The images were analysed with the open source program ImageJ. The five 3D-image print-outs copied from the subsample of the soil column were compared by means of their macropore network connectivity, porosity, surface volume, tortuosity and skeleton. The comparison of pore morphology between the real soil and the print-outs showed that Polyamide reproduced the soil macropore structure best while Alumide print-out was the least detailed. Only the largest macropore was represented in all five print-outs. Printing residual material or printing aid material remained in and clogged the pores of all print-out materials apart from Prime Grey. Therefore infiltration was blocked in these print-outs and the materials are not suitable even though the 3D-printed pore shapes were well reproduced. All of the investigated materials were insoluble. The sessile drop method showed angles between 53 and 85 degrees. Prime Grey had the fastest flow rate; the other conducting materials had slow or non-reproducible flow rates. Since only Prime Grey was able to print-out the largest macropore in a discontinuous way, the morphological differences between the five print-outs were not evaluated. Each material has its limitations but only Prime Greys morphology was sufficiently printed and no clogging with residual material occurred. Polyamide and High Detail Resin had clogged pores but were matching the soil's macropore morphology better but further research on removal of residual material blocking pores is needed before they are useable.

Crystal morphology optimization of thiamine hydrochloride in solvent system: Experimental and molecular dynamics simulation studies

NASA Astrophysics Data System (ADS)

Yang, Yang; Han, Dandan; Du, Shichao; Wu, Songgu; Gong, Junbo

2018-01-01

Thiamine hydrochloride (THCL) was produced in methanol accompanied with agglomeration in industry, the plate like morphology of THCL in methanol was not deserve to have a good quality. Selecting a suitable solvent should be considered because solvent could be one of the essential factors to impact morphology. Methanol and methanol/ethyl acetate solvent (0.2 vol fraction of methanol) was selected as the solvent system in reactive crystallization of THCL. The experiment results show the THCL crystal morphology in methanol/ethyl acetate solvent system was granular and more regular than that in methanol. In order to explicate the different crystal morphology in different solvents, molecular dynamics (MD) simulation was introduced to simulate crystal morphology in different solvents. The attachment energy (AE) model was employed to investigate the morphology of THCL under vacuum conditions, methanol and methanol/ethyl acetate solvent conditions, respectively. The simulation crystal morphology was in a good agreement with that of experimented. The particle of THCL in methanol/ethyl acetate solvent has less tendency to agglomeration, and then it is favorable to the downstream process, such as filtration, storage and transportation.

Preparation and cupric ion release behavior of Cu/LDPE porous composites with tunable pore morphology for intrauterine devices.

PubMed

Xiao, Lian; Xia, Xianping; Xie, Changsheng; Ge, Man; Xiao, Cheng; Cai, Shuizhou

2013-07-01

Copper/low-density polyethylene (Cu/LDPE) porous composites are novel materials for copper-containing intrauterine devices (Cu-IUDs). Here we report a method, i.e., by changing the mass ratio of two kinds of porogens that have different melting points through the combined techniques of injection molding and particulate leaching, to prepare the Cu/LDPE porous composites with tunable pore morphology. After these Cu/LDPE porous composites with different pore morphologies were obtained, the influences of pore morphologies on their cupric ion release behaviors were studied. The results show that the pore morphology has great influence on the cupric ion release behavior of Cu/LDPE porous composites. This phenomenon is caused by the different influences of different pore morphologies on the effective porosity and the surface hydrophilicity. And those results can be applied to guide the fabrication of Cu/LDPE porous composite Cu-IUDs with minimal weight at an appropriate cupric ion release rate. Copyright © 2013 Elsevier B.V. All rights reserved.

Nanomechanical clues from morphologically normal cervical squamous cells could improve cervical cancer screening

NASA Astrophysics Data System (ADS)

Geng, Li; Feng, Jiantao; Sun, Quanmei; Liu, Jing; Hua, Wenda; Li, Jing; Ao, Zhuo; You, Ke; Guo, Yanli; Liao, Fulong; Zhang, Youyi; Guo, Hongyan; Han, Jinsong; Xiong, Guangwu; Zhang, Lufang; Han, Dong

2015-09-01

Applying an atomic force microscope, we performed a nanomechanical analysis of morphologically normal cervical squamous cells (MNSCs) which are commonly used in cervical screening. Results showed that nanomechanical parameters of MNSCs correlate well with cervical malignancy, and may have potential in cancer screening to provide early diagnosis.Applying an atomic force microscope, we performed a nanomechanical analysis of morphologically normal cervical squamous cells (MNSCs) which are commonly used in cervical screening. Results showed that nanomechanical parameters of MNSCs correlate well with cervical malignancy, and may have potential in cancer screening to provide early diagnosis. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr03662c

Studies on morphology of Langmuir-Blodgett films of stearic acid deposited with different orientation of substrates with respect to compression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choudhary, Keerti; Manjuladevi, V.; Gupta, R. K., E-mail: raj@pilani.bits-pilani.ac.in

2016-05-06

The Langmuir monolayer at an air-water interface shows remarkably different surface pressure – area isotherm, when measured with the surface normal of a Wilhemly plate parallel or perpendicular to the direction of compression of the monolayer. Such difference arises due to difference in stress exerted by the monolayer on the plate in different direction. In this article, we report the effect of changing the direction of substrate normal with respect to the compression of the monolayer during Langmuir-Blodgett (LB) film deposition on the morphology of the films. The morphology of the LB film of stearic acid was studied using anmore » atomic force microscope (AFM). The morphology of the LB films was found to be different due to difference in the stress in different directions.« less

The Acetone Extract of Sclerocarya birrea (Anacardiaceae) Possesses Antiproliferative and Apoptotic Potential against Human Breast Cancer Cell Lines (MCF-7)

PubMed Central

Tanih, Nicoline Fri; Ndip, Roland Ndip

2013-01-01

Interesting antimicrobial data from the stem bark of Sclerocarya birrea, which support its use in traditional medicine for the treatment of many diseases, have been delineated. The current study was aimed to further study some pharmacological and toxicological properties of the plant to scientifically justify its use. Anticancer activity of water and acetone extracts of S. birrea was evaluated on three different cell lines, HT-29, HeLa, and MCF-7 using the cell titre blue viability assay in 96-well plates. Apoptosis was evaluated using the acridine orange and propidium iodide staining method, while morphological structure of treated cells was examined using SEM. The acetone extract exhibited remarkable antiproliferative activities on MCF-7 cell lines at dose- and time-dependent manners (24 h and 48 h of incubation). The extract also exerted apoptotic programmed cell death in MCF-7 cells with significant effect on the DNA. Morphological examination also displayed apoptotic characteristics in the treated cells, including clumping, condensation, and culminating to budding of the cells to produce membrane-bound fragmentation, as well as formation of apoptotic bodies. The acetone extract of S. birrea possesses antiproliferative and apoptotic potential against MCF-7-treated cells and could be further exploited as a potential lead in anticancer therapy. PMID:23576913

Bio-photonic detection method for morphological analysis of anthracnose disease and physiological disorders of Diospyros kaki

NASA Astrophysics Data System (ADS)

Wijesinghe, Ruchire Eranga; Lee, Seung-Yeol; Ravichandran, Naresh Kumar; Shirazi, Muhammad Faizan; Moon, Byungin; Jung, Hee-Young; Jeon, Mansik; Kim, Jeehyun

2017-04-01

The pathological and physiological defects in various types of fruits lead to large amounts of economical waste. It is well recognized that internal fruit defects due to pathological infections and physiological disorders can be effectively visualized at an initial stage of the disease using a well-known bio-photonic detection method called optical coherence tomography (OCT). This work investigates the use of OCT for identifying the morphological variations of anthracnose (bitter rot) disease infected and physiologically disordered Diospyros kaki (Asian Persimmon) fruits. An experiment was conducted using fruit samples that were carefully selected from persimmon orchards. Depth-resolved images with a high axial resolution were acquired using 850-nm-based spectral-domain OCT (SD-OCT) system. The obtained exemplary high-resolution two-dimensional and volumetric three-dimensional images revealed complementary morphological differences between healthy and defected samples. Moreover, the obtained depth-profile analysis results confirmed the disappearance of the healthy cell layers among the healthy-infected boundary regions. Thus, the proposed method has the potential to increase the diagnostic accuracy of the OCT technique used in agricultural plantations.

A novel copper/polydimethiylsiloxane nanocomposite for copper-containing intrauterine contraceptive devices.

PubMed

Xu, X X; Ding, M H; Zhang, J X; Zheng, W; Li, L; Zheng, Y F

2013-11-01

In this article, a novel composite of copper (Cu) nanoparticles and polydimethiylsiloxane (PDMS) has been prepared and investigated for the potential application in Cu-containing intrauterine device. The Cu/PDMS composite with various mass fraction of Cu nanoparticles was fabricated via the hot vulcanizing process. The chemical structures and surface morphologies of the Cu/PDMS composites were characterized confirming the physical interaction between Cu nanoparticles and PDMS. The surface morphology observation using scanning electron microscope and atomic force microscope showed the agglomeration of Cu nanoparticles in PDMS matrix and the distribution of the agglomerations was more uniform with increased amount of Cu nanoparticles. The cupric ion release behaviors of the Cu/PDMS composites with different amounts of Cu nanoparticles were investigated in simulated uterine fluid at 37°C for 150 days. The corrosion morphologies of the Cu/PDMS composites were also characterized. Both the burst release rate of the cupric ion in the first few days and the steady release rate after 30-day immersion were improved. The cytotoxicity test has been done for the Cu/PDMS composites. Copyright © 2013 Wiley Periodicals, Inc.

Effect of Yeast Cell Morphology, Cell Wall Physical Structure and Chemical Composition on Patulin Adsorption

PubMed Central

Luo, Ying; Wang, Jianguo; Liu, Bin; Wang, Zhouli; Yuan, Yahong; Yue, Tianli

2015-01-01

The capability of yeast to adsorb patulin in fruit juice can aid in substantially reducing the patulin toxic effect on human health. This study aimed to investigate the capability of yeast cell morphology and cell wall internal structure and composition to adsorb patulin. To compare different yeast cell morphologies, cell wall internal structure and composition, scanning electron microscope, transmission electron microscope and ion chromatography were used. The results indicated that patulin adsorption capability of yeast was influenced by cell surface areas, volume, and cell wall thickness, as well as 1,3-β-glucan content. Among these factors, cell wall thickness and 1,3-β-glucan content serve significant functions. The investigation revealed that patulin adsorption capability was mainly affected by the three-dimensional network structure of the cell wall composed of 1,3-β-glucan. Finally, patulin adsorption in commercial kiwi fruit juice was investigated, and the results indicated that yeast cells could adsorb patulin from commercial kiwi fruit juice efficiently. This study can potentially simulate in vitro cell walls to enhance patulin adsorption capability and successfully apply to fruit juice industry. PMID:26295574

Effect of Yeast Cell Morphology, Cell Wall Physical Structure and Chemical Composition on Patulin Adsorption.

PubMed

Luo, Ying; Wang, Jianguo; Liu, Bin; Wang, Zhouli; Yuan, Yahong; Yue, Tianli

2015-01-01

The capability of yeast to adsorb patulin in fruit juice can aid in substantially reducing the patulin toxic effect on human health. This study aimed to investigate the capability of yeast cell morphology and cell wall internal structure and composition to adsorb patulin. To compare different yeast cell morphologies, cell wall internal structure and composition, scanning electron microscope, transmission electron microscope and ion chromatography were used. The results indicated that patulin adsorption capability of yeast was influenced by cell surface areas, volume, and cell wall thickness, as well as 1,3-β-glucan content. Among these factors, cell wall thickness and 1,3-β-glucan content serve significant functions. The investigation revealed that patulin adsorption capability was mainly affected by the three-dimensional network structure of the cell wall composed of 1,3-β-glucan. Finally, patulin adsorption in commercial kiwi fruit juice was investigated, and the results indicated that yeast cells could adsorb patulin from commercial kiwi fruit juice efficiently. This study can potentially simulate in vitro cell walls to enhance patulin adsorption capability and successfully apply to fruit juice industry.

Neurogenic and cardiomyogenic differentiation of mesenchymal stem cells isolated from minipig bone marrow.

PubMed

Kumar, B Mohana; Maeng, Geun-Ho; Lee, Yeon-Mi; Kim, Tae-Ho; Lee, Jeong-Hyeon; Jeon, Byeong-Gyun; Ock, Sun-A; Yoo, Jae-Gyu; Rho, Gyu-Jin

2012-10-01

The present study investigated the potential of minipig bone marrow-mesenchymal stem cells (BM-MSCs) to differentiate in vitro into neuron- and cardiomyocyte-like cells. Isolated BM-MSCs exhibited a fibroblast-like morphology, expressed CD29, CD44 and CD90, and differentiated into osteocytes, adipocytes and chondrocytes. Upon induction in two different neuronal specific media, most of BM-MSCs acquired the distinctive morphological features and positively stained for nestin, neurofilament-M (NF-M), neuronal nuclei (NeuN), β-tubulin, galactocerebroside (Gal-C) and glial fibrillary acidic protein (GFAP). Expression of nestin, GFAP and NF-M was further demonstrated by RT-PCR and RT-qPCR. Following cardiomyogenic induction, MSCs exhibited a stick-like morphology with extended cytoplasmic processes, and formed cluster-like structures. The expression of cardiac specific markers α-smooth muscle actin, cardiac troponin T, desmin and α-cardiac actin was positive for immunofluorescence staining, and further confirmed by RT-PCR and RT-qPCR. In conclusion, our results showed the in vitro differentiation ability of porcine BM-MSCs into neuron-like and cardiomyocyte-like cells. Copyright © 2011 Elsevier Ltd. All rights reserved.

Emerging roles of apoptotic microtubules during the execution phase of apoptosis.

PubMed

Oropesa Ávila, Manuel; Fernández Vega, Alejandro; Garrido Maraver, Juan; Villanueva Paz, Marina; De Lavera, Isabel; De La Mata, Mario; Cordero, Mario D; Alcocer Gómez, Elizabet; Delgado Pavón, Ana; Álvarez Córdoba, Mónica; Cotán, David; Sánchez-Alcázar, José Antonio

2015-09-01

Apoptosis is a genetically programmed energy-dependent process of cell demise, characterized by specific morphological and biochemical events in which the activation of caspases has an essential role. During apoptosis the cytoskeleton participates actively in characteristic morphological rearrangements of the dying cell. This reorganisation has been assigned mainly to actinomyosin ring contraction, while microtubule and intermediate filaments are depolymerized at early stages of apoptosis. However, recent reports have showed that microtubules are reformed during the execution phase of apoptosis organizing an apoptotic microtubule network (AMN). AMN is organized behind plasma membrane, forming a cortical structure. Apoptotic microtubules repolymerization takes place in many cell types and under different apoptotic inducers. It has been hypothesized that AMN is critical for maintaining plasma membrane integrity and cell morphology during the execution phase of apoptosis. AMN disorganization leads apoptotic cells to secondary necrosis and the release of potential toxic molecules which can damage neighbor cells and promotes inflammation. Therefore, AMN formation during physiological apoptosis or in pathological apoptosis induced by anti-cancer treatments is essential for tissue homeostasis and the prevention of additional cell damage and inflammation. © 2015 Wiley Periodicals, Inc.

Morphological and functional aspects of progenitors perturbed in cortical malformations

PubMed Central

Bizzotto, Sara; Francis, Fiona

2015-01-01

In this review, we discuss molecular and cellular mechanisms important for the function of neuronal progenitors during development, revealed by their perturbation in different cortical malformations. We focus on a class of neuronal progenitors, radial glial cells (RGCs), which are renowned for their unique morphological and behavioral characteristics, constituting a key element during the development of the mammalian cerebral cortex. We describe how the particular morphology of these cells is related to their roles in the orchestration of cortical development and their influence on other progenitor types and post-mitotic neurons. Important for disease mechanisms, we overview what is currently known about RGC cellular components, cytoskeletal mechanisms, signaling pathways and cell cycle characteristics, focusing on how defects lead to abnormal development and cortical malformation phenotypes. The multiple recent entry points from human genetics and animal models are contributing to our understanding of this important cell type. Combining data from phenotypes in the mouse reveals molecules which potentially act in common pathways. Going beyond this, we discuss future directions that may provide new data in this expanding area. PMID:25729350

Inter-ethnic differences in valve morphology, valvular dysfunction, and aortopathy between Asian and European patients with bicuspid aortic valve.

PubMed

Kong, William K F; Regeer, Madelien V; Poh, Kian K; Yip, James W; van Rosendael, Philippe J; Yeo, Tiong C; Tay, Edgar; Kamperidis, Vasileios; van der Velde, Enno T; Mertens, Bart; Ajmone Marsan, Nina; Delgado, Victoria; Bax, Jeroen J

2018-04-14

Transcatheter aortic valve replacement (TAVR) has been shown safe and feasible in patients with bicuspid aortic valve (BAV) morphology. Evaluation of inter-ethnic differences in valve morphology and function and aortic root dimensions in patients with BAV is important for the worldwide spread of this therapy in this subgroup of patients. Comparisons between large European and Asian cohorts of patients with BAV have not been performed, and potential differences between populations may have important implications for TAVR. The present study evaluated the differences in valve morphology and function and aortic root dimensions between two large cohorts of European and Asian patients with BAV. Aortic valve morphology was defined on transthoracic echocardiography according to the number of commissures and raphe: type 0 = no raphe and two commissures, type 1 = one raphe and two commissures, type 2 = two raphes and one commissure. Aortic stenosis and regurgitation were graded according to current recommendations. For this study, aortic root dimensions were manually measured on transthoracic echocardiograms at the level of the aortic annulus, sinus of Valsalva (SOV), sinotubular junction (STJ), and ascending aorta (AA). Of 1427 patients with BAV (45.2 ± 18.1 years, 71.9% men), 794 (55.6%) were Europeans and 633 (44.4%) were Asians. The groups were comparable in age and proportion of male sex. Asians had higher prevalence of type 1 BAV with raphe between right and non-coronary cusps than Europeans (19.7% vs. 13.6%, respectively; P < 0.001), whereas the Europeans had higher prevalence of type 0 BAV (two commissures, no raphe) than Asians (14.5% vs. 6.8%, respectively; P < 0.001). The prevalence of moderate and severe aortic regurgitation was higher in Europeans than Asians (44.2% vs. 26.8%, respectively; P < 0.001) whereas there were no differences in BAV with normal function or aortic stenosis. After adjusting for demographics, comorbidities, and valve function, the dimensions of the aortic annulus [mean difference 1.17 mm/m2, 95% confidence interval (CI) 0.96-1.39], SOV (mean difference 1.86 mm/m2, 95% CI 1.47-2.24), STJ (mean difference 0.52 mm/m2, 95% CI 0.14-0.90) and AA (mean difference 1.05 mm/m2, 95% CI 0.57-1.52) were significantly larger among Asians compared with Europeans. This large multicentre registry reports for the first time that Asians with BAV showed more frequently type 1 BAV (with fusion between right and non-coronary cusp) and have larger aortic dimensions than Europeans. These findings have important implications for prosthesis type and size selection for TAVR.

Basal ganglia and thalamic morphology in schizophrenia and bipolar disorder.

PubMed

Womer, Fay Y; Wang, Lei; Alpert, Kathryn I; Smith, Matthew J; Csernansky, John G; Barch, Deanna M; Mamah, Daniel

2014-08-30

In this study, we examined the morphology of the basal ganglia and thalamus in bipolar disorder (BP), schizophrenia-spectrum disorders (SCZ-S), and healthy controls (HC) with particular interest in differences related to the absence or presence of psychosis. Volumetric and shape analyses of the basal ganglia and thalamus were performed in 33 BP individuals [12 without history of psychotic features (NPBP) and 21 with history of psychotic features (PBP)], 32 SCZ-S individuals [28 with SCZ and 4 with schizoaffective disorder], and 27 HC using FreeSurfer-initiated large deformation diffeomorphic metric mapping. Significant volume differences were found in the caudate and globus pallidus, with volumes smallest in the NPBP group. Shape abnormalities showing inward deformation of superior regions of the caudate were observed in BP (and especially in NPBP) compared with HC. Shape differences were also found in the globus pallidus and putamen when comparing BP and SCZ-S groups. No significant differences were seen in the nucleus accumbens and thalamus. In summary, structural abnormalities in the caudate and globus pallidus are present in BP and SCZ-S. Differences were more apparent in the NPBP subgroup. The findings herein highlight the potential importance of separately examining BP subgroups in neuroimaging studies. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Application for the Drosophila ventral nerve cord standard in neuronal circuit reconstruction and in-depth analysis of mutant morphology.

PubMed

Boerner, Jana; Godenschwege, Tanja Angela

2010-09-01

The Drosophila standard brain has been a useful tool that provides information about position and size of different brain structures within a wild-type brain and allows the comparison of imaging data that were collected from individual preparations. Therefore the standard can be used to reveal and visualize differences of brain regions between wild-type and mutant brains and can provide spatial description of single neurons within the nervous system. Recently the standard brain was complemented by the generation of a ventral nerve cord (VNC) standard. Here the authors have registered the major components of a simple neuronal circuit, the Giant Fiber System (GFS), into this standard. The authors show that they can also virtually reconstruct the well-characterized synaptic contact of the Giant Fiber with its motorneuronal target when they register the individual neurons from different preparations into the VNC standard. In addition to the potential application for the standard thorax in neuronal circuit reconstruction, the authors show that it is a useful tool for in-depth analysis of mutant morphology of single neurons. The authors find quantitative and qualitative differences when they compared the Giant Fibers of two different neuroglian alleles, nrg(849) and nrg(G00305), using the averaged wild-type GFS in the standard VNC as a reference.

Inhibition of stored Ca2+ release disrupts convergence-related cell movements in the lateral intermediate mesoderm resulting in abnormal positioning and morphology of the pronephric anlagen in intact zebrafish embryos.

PubMed

Lam, Pui Ying; Webb, Sarah E; Leclerc, Catherine; Moreau, Marc; Miller, Andrew L

2009-05-01

Ca(2+) is a highly versatile intra- and intercellular signal that has been reported to regulate a variety of different pattern-forming processes during early development. To investigate the potential role of Ca(2+) signaling in regulating convergence-related cell movements, and the positioning and morphology of the pronephric anlagen, we treated zebrafish embryos from 11.5 h postfertilization (hpf; i.e. just before the pronephric anlagen are morphologically distinguishable in the lateral intermediate mesoderm; LIM) to 16 hpf, with a variety of membrane permeable pharmacological reagents known to modulate [Ca(2+)](i). The effect of these treatments on pronephric anlagen positioning and morphology was determined in both fixed and live embryos via in situ hybridization using the pronephic-specific probes, cdh17, pax2.1 and sim1, and confocal imaging of BODIPY FL C(5)-ceramide-labeled embryos, respectively. We report that Ca(2+) released from intracellular stores via inositol 1,4,5-trisphosphate receptors plays a significant role in the positioning and morphology of the pronephric anlagen, but does not affect the fate determination of the LIM cells that form these primordia. Our data suggest that when Ca(2+) release is inhibited, the resulting effects on the pronephric anlagen are a consequence of the disruption of normal convergence-related movements of LIM cells toward the embryonic midline.

Nocturnality constrains morphological and functional diversity in the eyes of reef fishes.

PubMed

Schmitz, Lars; Wainwright, Peter C

2011-11-19

Ambient light levels are often considered to drive the evolution of eye form and function. Diel activity pattern is the main mechanism controlling the visual environment of teleost reef fish, with day-active (diurnal) fish active in well-illuminated conditions, whereas night-active (nocturnal) fish cope with dim light. Physiological optics predicts several specific evolutionary responses to dim-light vision that should be reflected in visual performance features of the eye. We analyzed a large comparative dataset on morphological traits of the eyes in 265 species of teleost reef fish in 43 different families. The eye morphology of nocturnal reef teleosts is characterized by a syndrome that indicates better light sensitivity, including large relative eye size, high optical ratio and large, rounded pupils. Improved dim-light image formation comes at the cost of reduced depth of focus and reduction of potential accommodative lens movement. Diurnal teleost reef fish, released from the stringent functional requirements of dim-light vision have much higher morphological and optical diversity than nocturnal species, with large ranges of optical ratio, depth of focus, and lens accommodation. Physical characteristics of the environment are an important factor in the evolution and diversification of the vertebrate eye. Both teleost reef fish and terrestrial amniotes meet the functional requirements of dim-light vision with a similar evolutionary response of morphological and optical modifications. The trade-off between improved dim-light vision and reduced optical diversity may be a key factor in explaining the lower trophic diversity of nocturnal reef teleosts.

Utility of combining morphological characters, nuclear and mitochondrial genes: An attempt to resolve the conflicts of species identification for ciliated protists.

PubMed

Zhao, Yan; Yi, Zhenzhen; Gentekaki, Eleni; Zhan, Aibin; Al-Farraj, Saleh A; Song, Weibo

2016-01-01

Ciliates comprise a highly diverse protozoan lineage inhabiting all biotopes and playing crucial roles in regulating microbial food webs. Nevertheless, subtle morphological differences and tiny sizes hinder proper species identification for many ciliates. Here, we use the species-rich taxon Frontonia and employ both nuclear and mitochondrial loci. We attempt to assess the level of genetic diversity and evaluate the potential of each marker in delineating species of Frontonia. Morphological features and ecological characteristics are also integrated into genetic results, in an attempt to resolve conflicts of species identification based on morphological and molecular methods. Our studies reveal: (1) the mitochondrial cox1 gene, nuclear ITS1 and ITS2 as well as the hypervariable D2 region of LSU rDNA are promising candidates for species delineation; (2) the cox1 gene provides the best resolution for analyses below the species level; (3) the V2 and V4 hypervariable regions of SSU rDNA, and D1 of LSU rDNA as well as the 5.8S rDNA gene do not show distinct barcoding gap due to overlap between intra- and inter-specific genetic divergences; (4) morphological character-based analysis shows promise for delimitation of Frontonia species; and (5) all gene markers and character-based analyses demonstrate that the genus Frontonia consists of three groups and monophyly of the genus Frontonia is questionable. Copyright © 2015 Elsevier Inc. All rights reserved.

Performance analysis of deciduous morphology for detecting biological siblings.

PubMed

Paul, Kathleen S; Stojanowski, Christopher M

2015-08-01

Family-centered burial practices influence cemetery structure and can represent social group composition in both modern and ancient contexts. In ancient sites dental phenotypic data are often used as proxies for underlying genotypes to identify potential biological relatives. Here, we test the performance of deciduous dental morphological traits for differentiating sibling pairs from unrelated individuals from the same population. We collected 46 deciduous morphological traits for 69 sibling pairs from the Burlington Growth Centre's long term Family Study. Deciduous crown features were recorded following published standards. After variable winnowing, inter-individual Euclidean distances were generated using 20 morphological traits. To determine whether sibling pairs are more phenotypically similar than expected by chance we used bootstrap resampling of distances to generate P values. Multidimensional scaling (MDS) plots were used to evaluate the degree of clustering among sibling pairs. Results indicate an average distance between siblings of 0.252, which is significantly less than 9,999 replicated averages of 69 resampled pseudo-distances generated from: 1) a sample of non-relative pairs (P < 0.001), and 2) a sample of relative and non-relative pairs (P < 0.001). MDS plots indicate moderate to strong clustering among siblings; families occupied 3.83% of the multidimensional space on average (versus 63.10% for the total sample). Deciduous crown morphology performed well in identifying related sibling pairs. However, there was considerable variation in the extent to which different families exhibited similarly low levels of phenotypic divergence. © 2015 Wiley Periodicals, Inc.

Quantitative Outline-based Shape Analysis and Classification of Planetary Craterforms using Supervised Learning Models

NASA Astrophysics Data System (ADS)

Slezak, Thomas Joseph; Radebaugh, Jani; Christiansen, Eric

2017-10-01

The shapes of craterform morphology on planetary surfaces provides rich information about their origins and evolution. While morphologic information provides rich visual clues to geologic processes and properties, the ability to quantitatively communicate this information is less easily accomplished. This study examines the morphology of craterforms using the quantitative outline-based shape methods of geometric morphometrics, commonly used in biology and paleontology. We examine and compare landforms on planetary surfaces using shape, a property of morphology that is invariant to translation, rotation, and size. We quantify the shapes of paterae on Io, martian calderas, terrestrial basaltic shield calderas, terrestrial ash-flow calderas, and lunar impact craters using elliptic Fourier analysis (EFA) and the Zahn and Roskies (Z-R) shape function, or tangent angle approach to produce multivariate shape descriptors. These shape descriptors are subjected to multivariate statistical analysis including canonical variate analysis (CVA), a multiple-comparison variant of discriminant analysis, to investigate the link between craterform shape and classification. Paterae on Io are most similar in shape to terrestrial ash-flow calderas and the shapes of terrestrial basaltic shield volcanoes are most similar to martian calderas. The shapes of lunar impact craters, including simple, transitional, and complex morphology, are classified with a 100% rate of success in all models. Multiple CVA models effectively predict and classify different craterforms using shape-based identification and demonstrate significant potential for use in the analysis of planetary surfaces.

Quantitative assessment of cancer cell morphology and motility using telecentric digital holographic microscopy and machine learning.

PubMed

Lam, Van K; Nguyen, Thanh C; Chung, Byung M; Nehmetallah, George; Raub, Christopher B

2018-03-01

The noninvasive, fast acquisition of quantitative phase maps using digital holographic microscopy (DHM) allows tracking of rapid cellular motility on transparent substrates. On two-dimensional surfaces in vitro, MDA-MB-231 cancer cells assume several morphologies related to the mode of migration and substrate stiffness, relevant to mechanisms of cancer invasiveness in vivo. The quantitative phase information from DHM may accurately classify adhesive cancer cell subpopulations with clinical relevance. To test this, cells from the invasive breast cancer MDA-MB-231 cell line were cultured on glass, tissue-culture treated polystyrene, and collagen hydrogels, and imaged with DHM followed by epifluorescence microscopy after staining F-actin and nuclei. Trends in cell phase parameters were tracked on the different substrates, during cell division, and during matrix adhesion, relating them to F-actin features. Support vector machine learning algorithms were trained and tested using parameters from holographic phase reconstructions and cell geometric features from conventional phase images, and used to distinguish between elongated and rounded cell morphologies. DHM was able to distinguish between elongated and rounded morphologies of MDA-MB-231 cells with 94% accuracy, compared to 83% accuracy using cell geometric features from conventional brightfield microscopy. This finding indicates the potential of DHM to detect and monitor cancer cell morphologies relevant to cell cycle phase status, substrate adhesion, and motility. © 2017 International Society for Advancement of Cytometry. © 2017 International Society for Advancement of Cytometry.

Morphological Plant Modeling: Unleashing Geometric and Topological Potential within the Plant Sciences

PubMed Central

Bucksch, Alexander; Atta-Boateng, Acheampong; Azihou, Akomian F.; Battogtokh, Dorjsuren; Baumgartner, Aly; Binder, Brad M.; Braybrook, Siobhan A.; Chang, Cynthia; Coneva, Viktoirya; DeWitt, Thomas J.; Fletcher, Alexander G.; Gehan, Malia A.; Diaz-Martinez, Diego Hernan; Hong, Lilan; Iyer-Pascuzzi, Anjali S.; Klein, Laura L.; Leiboff, Samuel; Li, Mao; Lynch, Jonathan P.; Maizel, Alexis; Maloof, Julin N.; Markelz, R. J. Cody; Martinez, Ciera C.; Miller, Laura A.; Mio, Washington; Palubicki, Wojtek; Poorter, Hendrik; Pradal, Christophe; Price, Charles A.; Puttonen, Eetu; Reese, John B.; Rellán-Álvarez, Rubén; Spalding, Edgar P.; Sparks, Erin E.; Topp, Christopher N.; Williams, Joseph H.; Chitwood, Daniel H.

2017-01-01

The geometries and topologies of leaves, flowers, roots, shoots, and their arrangements have fascinated plant biologists and mathematicians alike. As such, plant morphology is inherently mathematical in that it describes plant form and architecture with geometrical and topological techniques. Gaining an understanding of how to modify plant morphology, through molecular biology and breeding, aided by a mathematical perspective, is critical to improving agriculture, and the monitoring of ecosystems is vital to modeling a future with fewer natural resources. In this white paper, we begin with an overview in quantifying the form of plants and mathematical models of patterning in plants. We then explore the fundamental challenges that remain unanswered concerning plant morphology, from the barriers preventing the prediction of phenotype from genotype to modeling the movement of leaves in air streams. We end with a discussion concerning the education of plant morphology synthesizing biological and mathematical approaches and ways to facilitate research advances through outreach, cross-disciplinary training, and open science. Unleashing the potential of geometric and topological approaches in the plant sciences promises to transform our understanding of both plants and mathematics. PMID:28659934

Protein expression differs between neural progenitor cells from the adult rat brain subventricular zone and olfactory bulb.

PubMed

Maurer, Martin H; Feldmann, Robert E; Bürgers, Heinrich F; Kuschinsky, Wolfgang

2008-01-16

Neural progenitor cells can be isolated from various regions of the adult mammalian brain, including the forebrain structures of the subventricular zone and the olfactory bulb. Currently it is unknown whether functional differences in these progenitor cell populations can already be found on the molecular level. Therefore, we compared protein expression profiles between progenitor cells isolated from the subventricular zone and the olfactory bulb using a proteomic approach based on two-dimensional gel electrophoresis and mass spectrometry. The subventricular zone and the olfactory bulb are connected by the Rostral Migratory Stream (RMS), in which glial fibrillary acidic protein (GFAP)-positive cells guide neuroblasts. Recent literature suggested that these GFAP-positive cells possess neurogenic potential themselves. In the current study, we therefore compared the cultured neurospheres for the fraction of GFAP-positive cells and their morphology of over a prolonged period of time. We found significant differences in the protein expression patterns between subventricular zone and olfactory bulb neural progenitor cells. Of the differentially expressed protein spots, 105 were exclusively expressed in the subventricular zone, 23 showed a lower expression and 51 a higher expression in the olfactory bulb. The proteomic data showed that more proteins are differentially expressed in olfactory bulb progenitors with regard to proteins involved in differentiation and microenvironmental integration, as compared to the subventricular zone progenitors. Compared to 94% of all progenitors of the subventricular zone expressed GFAP, nearly none in the olfactory bulb cultures expressed GFAP. Both GFAP-positive subpopulations differed also in morphology, with the olfactory bulb cells showing more branching. No differences in growth characteristics such as doubling time, and passage lengths could be found over 26 consecutive passages in the two cultures. In this study, we describe differences in protein expression of neural progenitor populations isolated from two forebrain regions, the subventricular zone and the olfactory bulb. These subpopulations can be characterized by differential expression of marker proteins. We isolated fractions of progenitor cells with GFAP expression from both regions, but the GFAP-positive cells differed in number and morphology. Whereas in vitro growth characteristics of neural progenitors are preserved in both regions, our proteomic and immunohistochemical data suggest that progenitor cells from the two regions differ in morphology and functionality, but not in their proliferative capacity.

Electrochemical stability and postmortem studies of Pt/SiC catalysts for polymer electrolyte membrane fuel cells.

PubMed

Stamatin, Serban N; Speder, Jozsef; Dhiman, Rajnish; Arenz, Matthias; Skou, Eivind M

2015-03-25

In the presented work, the electrochemical stability of platinized silicon carbide is studied. Postmortem transmission electron microscopy and X-ray photoelectron spectroscopy were used to document the change in the morphology and structure upon potential cycling of Pt/SiC catalysts. Two different potential cycle aging tests were used in order to accelerate the support corrosion, simulating start-up/shutdown and load cycling. On the basis of the results, we draw two main conclusions. First, platinized silicon carbide exhibits improved electrochemical stability over platinized active carbons. Second, silicon carbide undergoes at least mild oxidation if not even silicon leaching.

Testing Convergence Versus History: Convergence Dominates Phenotypic Evolution for over 150 Million Years in Frogs.

PubMed

Moen, Daniel S; Morlon, Hélène; Wiens, John J

2016-01-01

Striking evolutionary convergence can lead to similar sets of species in different locations, such as in cichlid fishes and Anolis lizards, and suggests that evolution can be repeatable and predictable across clades. Yet, most examples of convergence involve relatively small temporal and/or spatial scales. Some authors have speculated that at larger scales (e.g., across continents), differing evolutionary histories will prevent convergence. However, few studies have compared the contrasting roles of convergence and history, and none have done so at large scales. Here we develop a two-part approach to test the scale over which convergence can occur, comparing the relative importance of convergence and history in macroevolution using phylogenetic models of adaptive evolution. We apply this approach to data from morphology, ecology, and phylogeny from 167 species of anuran amphibians (frogs) from 10 local sites across the world, spanning ~160 myr of evolution. Mapping ecology on the phylogeny revealed that similar microhabitat specialists (e.g., aquatic, arboreal) have evolved repeatedly across clades and regions, producing many evolutionary replicates for testing for morphological convergence. By comparing morphological optima for clades and microhabitat types (our first test), we find that convergence associated with microhabitat use dominates frog morphological evolution, producing recurrent ecomorphs that together encompass all sampled species in each community in each region. However, our second test, which examines whether and how much species differ from their inferred optima, shows that convergence is incomplete: that is, phenotypes of most species are still somewhat distant from the estimated optimum for each microhabitat, seemingly because of insufficient time for more complete adaptation (an effect of history). Yet, these effects of history are related to past ecologies, and not clade membership. Overall, our study elucidates the dominant drivers of morphological evolution across a major vertebrate clade and shows that evolution can be repeatable at much greater temporal and spatial scales than commonly thought. It also provides an analytical framework for testing other potential examples of large-scale convergence. © The Author(s) 2015. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Field trial of insect-resistant and herbicide-tolerant genetically modified cotton (Gossypium hirsutum L.) for environmental risk assessment in Japan.

PubMed

Asanuma, Yoko; Gondo, Takahiro; Ishigaki, Genki; Inoue, Koichi; Zaita, Norihiro; Muguerza, Melody; Akashi, Ryo

2017-04-03

Japan imports cottonseed mainly from Australia and the USA where more than 96% of all cotton varieties grown are genetically modified (GM). GM crops undergo an environmental risk assessment (ERA) under the Law Concerning the Conservation and Sustainable Use of Biological Diversity before import into Japan. Potential adverse effects on biodiversity are comprehensively assessed based on competitiveness, production of harmful substances and outcrossing ability. Even though imported cottonseed is intended for food and feed uses and not for cultivation, the potential risks from seed spillage during transport must be evaluated. In most cases, the ERA requires data collected from in-country field trials to demonstrate how the GM crop behaves in Japan's environment. Confined field trials in Japan were conducted for the ERA of Lepidoptera-resistant and glufosinate-tolerant GM cotton (Gossypium hirsutum L.) lines GHB119 and T304-40. These lines were compared with conventional varieties for growth habit, morphological characteristics, seed dormancy, and allelopathic activity associated with competitiveness and production of harmful substances. Outcrossing ability was not a concern due to the absence of sexually compatible wild relatives in Japan. Although slight statistical differences were observed between the GM line and its conventional comparator for some morphological characteristics, transgenes or transformation were not considered to be responsible for these differences. The trial demonstrated that competitiveness and production of harmful substances by these GM cotton lines were equivalent to conventional cotton varieties that have a long history of safe use, and no potential adverse effects to biosafety in Japan were observed.

Field trial of insect-resistant and herbicide-tolerant genetically modified cotton (Gossypium hirsutum L.) for environmental risk assessment in Japan

PubMed Central

Asanuma, Yoko; Gondo, Takahiro; Ishigaki, Genki; Inoue, Koichi; Zaita, Norihiro; Muguerza, Melody; Akashi, Ryo

2017-01-01

ABSTRACT Japan imports cottonseed mainly from Australia and the USA where more than 96% of all cotton varieties grown are genetically modified (GM). GM crops undergo an environmental risk assessment (ERA) under the Law Concerning the Conservation and Sustainable Use of Biological Diversity before import into Japan. Potential adverse effects on biodiversity are comprehensively assessed based on competitiveness, production of harmful substances and outcrossing ability. Even though imported cottonseed is intended for food and feed uses and not for cultivation, the potential risks from seed spillage during transport must be evaluated. In most cases, the ERA requires data collected from in-country field trials to demonstrate how the GM crop behaves in Japan's environment. Confined field trials in Japan were conducted for the ERA of Lepidoptera-resistant and glufosinate-tolerant GM cotton (Gossypium hirsutum L.) lines GHB119 and T304-40. These lines were compared with conventional varieties for growth habit, morphological characteristics, seed dormancy, and allelopathic activity associated with competitiveness and production of harmful substances. Outcrossing ability was not a concern due to the absence of sexually compatible wild relatives in Japan. Although slight statistical differences were observed between the GM line and its conventional comparator for some morphological characteristics, transgenes or transformation were not considered to be responsible for these differences. The trial demonstrated that competitiveness and production of harmful substances by these GM cotton lines were equivalent to conventional cotton varieties that have a long history of safe use, and no potential adverse effects to biosafety in Japan were observed. PMID:28510512

Growth potential limits drought morphological plasticity in seedlings from six Eucalyptus provenances.

PubMed

Maseda, Pablo H; Fernández, Roberto J

2016-02-01

Water stress modifies plant above- vs belowground biomass allocation, i.e., morphological plasticity. It is known that all species and genotypes reduce their growth rate in response to stress, but in the case of water stress it is unclear whether the magnitude of such reduction is linked to the genotype's growth potential, and whether the reduction can be largely attributed to morphological adjustments such as plant allocation and leaf and root anatomy. We subjected seedlings of six seed sources, three from each of Eucalyptus camaldulensis (potentially fast growing) and E. globulus (inherently slow growing), to three experimental water regimes. Biomass, leaf area and root length were measured in a 6-month glasshouse experiment. We then performed functional growth analysis of relative growth rate (RGR), and aboveground (leaf area ratio (LAR), specific leaf area (SLA) and leaf mass ratio (LMR)) and belowground (root length ratio (RLR), specific root length (SRL) and root mass ratio (RMR)) morphological components. Total biomass, root biomass and leaf area were reduced for all Eucalyptus provenances according to drought intensity. All populations exhibited drought plasticity, while those of greater growth potential (RGRmax) had a larger reduction in growth (discounting the effect of size). A positive correlation was observed between drought sensitivity and RGRmax. Aboveground, drought reduced LAR and LMR; under severe drought a negative correlation was found between LMR and RGRmax. Belowground, drought reduced SRL but increased RMR, resulting in no change in RLR. Under severe drought, a negative correlation was found between RLR, SRL and RGRmax. Our evidence strongly supports the classic ecophysiological trade-off between growth potential and drought tolerance for woody seedlings. It also suggests that slow growers would have a low capacity to adjust their morphology. For shoots, this constraint on plasticity was best observed in partition (i.e., LMR) whereas for roots it was clearest in morphology/anatomy (i.e., SRL). Thus, a low RGRmax would limit plastic response to drought not only at the whole plant level but also at the organ and even the tissue level. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Effect of morphology on the non-ohmic conduction in ZnO nanostructures

NASA Astrophysics Data System (ADS)

Praveen, E.; Jayakumar, K.

2016-05-01

Nanostructures of ZnO is synthesized with nanoflower like morphology by simple wet chemical method. The structural, morphological and electrical characterization have been carried out. The temperature dependent electrical characterization of ZnO pellets of thickness 1150 µm is made by the application of 925MPa pressure. The morphological dependence of non-ohmic conduction beyond some arbitrary tunneling potential and grain boundary barrier thickness is compared with the commercially available bulk ZnO. Our results show the suitability of nano-flower like ZnO for the devices like sensors, rectifiers etc.

Influences of pea morphology and interacting factors on pea aphid (Homoptera: Aphididae) reproduction.

PubMed

Buchman, N; Cuddington, K

2009-08-01

It has been claimed that plant architecture can alter aphid reproductive rates, but the mechanism driving this effect has not been identified. We studied interactions between plant architecture, aphid density, environmental conditions, and nutrient availability on the reproduction of pea aphids [Acyrthosiphon pisum (Harris)] using four near-isogenic peas (Pisum sativum L.) that differ in morphology. Manipulations of aphid density (1, 5, and 10 adults per plant) allowed us to examine any effects of plant morphology on crowding and consequently reproduction. Pea morphology per se did not alter pea aphid crowding, as measured by mean nearest neighbor distance, and there was no effect on reproduction. In addition, reproduction increased with increasing adult density, indicating positive density dependence. In a separate experiment, peas were fertilized to determine whether differences between nutrient availability of the four different morphologies might drive any observed differences in aphid reproduction. Although plant nitrogen content was altered by fertilization treatments, this did not have an impact on aphid reproduction. Greenhouse experiments, however, suggested that pea morphology can interact with environmental conditions to reduce aphid reproduction under some conditions. We conclude that plant morphology only influences aphid reproduction when environmental conditions are less than optimal.

Preparation of nano-hydroxyapatite particles with different morphology and their response to highly malignant melanoma cells in vitro

NASA Astrophysics Data System (ADS)

Li, Bo; Guo, Bo; Fan, Hongsong; Zhang, Xingdong

2008-11-01

To investigate the effects of nano-hydroxyapatite (HA) particles with different morphology on highly malignant melanoma cells, three kinds of HA particles with different morphology were synthesized and co-cultured with highly malignant melanoma cells using phosphate-buffered saline (PBS) as control. A precipitation method with or without citric acid addition as surfactant was used to produce rod-like hydroxyapatite (HA) particles with nano- and micron size, respectively, and a novel oil-in-water emulsion method was employed to prepare ellipse-like nano-HA particles. Particle morphology and size distribution of the as prepared HA powders were characterized by transmission electron microscope (TEM) and dynamic light scattering technique. The nano- and micron HA particles with different morphology were co-cultured with highly malignant melanoma cells. Immunofluorescence analysis and MTT assay were employed to evaluate morphological change of nucleolus and proliferation of tumour cells, respectively. To compare the effects of HA particles on cell response, the PBS without HA particles was used as control. The experiment results indicated that particle nanoscale effect rather than particle morphology of HA was more effective for the inhibition on highly malignant melanoma cells proliferation.

The influence of semantic and morphological complexity of verbs on sentence recall: Implications for the nature of conceptual representation and category-specific deficits.

PubMed

Mobayyen, Forouzan; de Almeida, Roberto G

2005-03-01

One hundred and forty normal undergraduate students participated in a Proactive Interference (PI) experiment with sentences containing verbs from four different semantic and morphological classes (lexical causatives, morphological causatives, and morphologically complex and simplex perception verbs). Past research has shown significant PI build-up effects for semantically and morphologically complex verbs in isolation (de Almeida & Mobayyen, 2004). The results of the present study show that, when embedded into sentence contexts, semantically and morphologically complex verbs do not produce significant PI build-up effects. Different verb classes, however, yield different recall patterns: sentences with semantically complex verbs (e.g., causatives) were recalled significantly better than sentences with semantically simplex verbs (e.g., perception verbs). The implications for the nature of both verb-conceptual representations and category-specific semantic deficits are discussed.

Efficacy of evaluation of rooster sperm morphology using different staining methods.

PubMed

Lukaszewicz, E; Jerysz, A; Partyka, A; Siudzińska, A

2008-12-01

This work focused on inexpensive methods of evaluation fowl sperm morphology, based on eosin-nigrosin smears, which can determine disorders in spermatogenesis and can be recommended for evaluating the fertilising potency and selecting males in flocks reproduced by artificial insemination. Four fowl breeds (Black Minorca, Italian Partridge, Forwerk and Greenleg Partridge) were used to determine the efficacy of sperm morphology evaluation using four eosin-nigrosin staining methods (according to Blom, Bakst and Cecil, Morisson, Jaśkowski) and three examiners of different experience (high, medium, novice). There were significant (P< or = 0.01) differences in sperm morphology between Blom's staining method and those of Bakst and Cecil, Morisson or Jaśkowski, irrespective of fowl breed and examiners experience. Blom stain caused sperm head swelling and showed a drastic reduction in the proportion of live spermatozoa with normal morphology. The staining method had a greater influence on sperm morphology evaluation than the experience of the examiners.

Wetting morphologies on randomly oriented fibers.

PubMed

Sauret, Alban; Boulogne, François; Soh, Beatrice; Dressaire, Emilie; Stone, Howard A

2015-06-01

We characterize the different morphologies adopted by a drop of liquid placed on two randomly oriented fibers, which is a first step toward understanding the wetting of fibrous networks. The present work reviews previous modeling for parallel and touching crossed fibers and extends it to an arbitrary orientation of the fibers characterized by the tilting angle and the minimum spacing distance. Depending on the volume of liquid, the spacing distance between fibers and the angle between the fibers, we highlight that the liquid can adopt three different equilibrium morphologies: 1) a column morphology in which the liquid spreads between the fibers, 2) a mixed morphology where a drop grows at one end of the column or 3) a single drop located at the node. We capture the different morphologies observed using an analytical model that predicts the equilibrium configuration of the liquid based on the geometry of the fibers and the volume of liquid.

Effect of etching time on morphological, optical, and electronic properties of silicon nanowires

PubMed Central

2012-01-01

Owing to their interesting electronic, mechanical, optical, and transport properties, silicon nanowires (SiNWs) have attracted much attention, giving opportunities to several potential applications in nanoscale electronic, optoelectronic devices, and silicon solar cells. For photovoltaic application, a superficial film of SiNWs could be used as an efficient antireflection coating. In this work we investigate the morphological, optical, and electronic properties of SiNWs fabricated at different etching times. Characterizations of the formed SiNWs films were performed using a scanning electron microscope, ultraviolet–visible-near-infrared spectroscopy, and light-beam-induced-current technique. The latter technique was used to determine the effective diffusion length in SiNWs films. From these investigations, we deduce that the homogeneity of the SiNWs film plays a key role on the electronic properties. PMID:22799265

Investigation of the asymmetric misfit dislocation morphology in epitaxial layers with the zinc-blende structure

NASA Technical Reports Server (NTRS)

Fox, Bradley A.; Jesser, William A.

1990-01-01

The source of the asymmetry in the dislocation morphology exhibited in the epitaxial growth of compound semiconductors on (100) was investigated. A thickness wedge of p- and n-type GaAs(0.95)P(0.05) was grown on GaAs by metalorganic chemical vapor deposition, and the effect of misorientation on the resolved shear stress for each slip system was calculated and eliminated as the source of the asymmetry. Another potential source of asymmetry, the thickness gradient, was also eliminated. Results show that the substrate misorientation and the thickness gradient do not significantly contribute to the asymmetry and that the dominant contributor to the asymmetry of misfit dislocations in the (001) epitaxial interface can be attributed to the differences in the Peierls barriers between the two types of dilocations in GaAsP/GaAs.

Characterization of fungi isolated from the equipment used in the International Space Station or Space Shuttle.

PubMed

Satoh, Kazuo; Yamazaki, Takashi; Nakayama, Takako; Umeda, Yoshiko; Alshahni, Mohamed Mahdi; Makimura, Miho; Makimura, Koichi

2016-05-01

As a part of a series of studies regarding the microbial biota in manned space environments, fungi were isolated from six pieces of equipment recovered from the Japanese Experimental Module "KIBO" of the International Space Station and from a space shuttle. Thirty-seven strains of fungi were isolated, identified and investigated with regard to morphological phenotypes and antifungal susceptibilities. The variety of fungi isolated in this study was similar to that of several previous reports. The dominant species belonged to the genera Penicillium, Aspergillus and Cladosporium, which are potential causative agents of allergy and opportunistic infections. The morphological phenotypes and antifungal susceptibilities of the strains isolated from space environments were not significantly different from those of reference strains on Earth. © 2016 The Societies and John Wiley & Sons Australia, Ltd.

Major Variations in HIV-1 Capsid Assembly Morphologies Involve Minor Variations in Molecular Structures of Structurally Ordered Protein Segments*

PubMed Central

Lu, Jun-Xia; Bayro, Marvin J.; Tycko, Robert

2016-01-01

We present the results of solid state nuclear magnetic resonance (NMR) experiments on HIV-1 capsid protein (CA) assemblies with three different morphologies, namely wild-type CA (WT-CA) tubes with 35–60 nm diameters, planar sheets formed by the Arg18-Leu mutant (R18L-CA), and R18L-CA spheres with 20–100 nm diameters. The experiments are intended to elucidate molecular structural variations that underlie these variations in CA assembly morphology. We find that multidimensional solid state NMR spectra of 15N,13C-labeled CA assemblies are remarkably similar for the three morphologies, with only small differences in 15N and 13C chemical shifts, no significant differences in NMR line widths, and few differences in the number of detectable NMR cross-peaks. Thus, the pronounced differences in morphology do not involve major differences in the conformations and identities of structurally ordered protein segments. Instead, morphological variations are attributable to variations in conformational distributions within disordered segments, which do not contribute to the solid state NMR spectra. Variations in solid state NMR signals from certain amino acid side chains are also observed, suggesting differences in the intermolecular dimerization interface between curved and planar CA lattices, as well as possible differences in intramolecular helix-helix packing. PMID:27129282