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Sample records for morphological changes

  1. Change Detection via Morphological Comparative Filters

    NASA Astrophysics Data System (ADS)

    Vizilter, Y. V.; Rubis, A. Y.; Zheltov, S. Y.; Vygolov, O. V.

    2016-06-01

    In this paper we propose the new change detection technique based on morphological comparative filtering. This technique generalizes the morphological image analysis scheme proposed by Pytiev. A new class of comparative filters based on guided contrasting is developed. Comparative filtering based on diffusion morphology is implemented too. The change detection pipeline contains: comparative filtering on image pyramid, calculation of morphological difference map, binarization, extraction of change proposals and testing change proposals using local morphological correlation coefficient. Experimental results demonstrate the applicability of proposed approach.

  2. WHITE CLOVER MORPHOLOGY CHANGES WITH STRESS TREATMENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The plasticity of white clover (Trifolium repens L.) results in morphological changes in plant habit in response to different environmental stresses. This research characterized morphological changes in white clover clones derived either from two cultivars and a germplasm exposed to treatments in 2-...

  3. Morphology Changing at Incipient Crystallization Condition

    NASA Astrophysics Data System (ADS)

    Toshima, Takeshi; Hamai, Ryo; Fujita, Saya; Takemura, Yuka; Takamatsu, Saori; Tafu, Masamoto

    2015-04-01

    Brushite (Dicalcium phosphate dihydrate, (DCPD), CaHPO4·2H2O) is one of key components in calcium phosphate system due to wide attractive material not only as bioceramics but also environmental materials. Morphology of DCPD crystals is important factor when one uses its functionality with chemical reaction; because its surface crystal face, shape and size rule the chemical reactivity, responsiveness. Moreover, physical properties are also changed the morphology; such as cohesion, dispersiveness, permeability and so on. If one uses DCPD crystals as environmental renovation materials to catch the fluoride ions, their shape require 020 crystal surfaces; which usually restricts their shape as plate-like structure. After the chemical reaction, the shape of sludge is not good for handling due to their agglutinate property. Therefore searching an effective parameter and developing the method to control the morphology of DCPD crystals is required. In past, we reported that initial concentration and pH value of starting solution, prepared by dissolving calcium nitrate, Ca(NO3)2 and ammonium dihydrogen phosphate, NH4H2PO4, changes the morphology of DCPD crystals and phase diagram of morphology of DCPD crystal depend on those parameter. The DCPD crystallization shows unique behaviour; products obtained higher initial concentration form single crystal-like structure and under lower condition, they form agglomerate crystal-like structure. These results contradict usual crystallization. Here we report that the effect of mixing process of two solutions. The morphology of DCPD crystals is changed from plate structure to petal structure by the arrangement. Our result suggests that morphology of DCPD crystals strongly depends at incipient crystallization condition and growth form is controllable by setting initial crystallization condition.

  4. Leaf morphology shift linked to climate change

    PubMed Central

    Guerin, Greg R.; Wen, Haixia; Lowe, Andrew J.

    2012-01-01

    Climate change is driving adaptive shifts within species, but research on plants has been focused on phenology. Leaf morphology has demonstrated links with climate and varies within species along climate gradients. We predicted that, given within-species variation along a climate gradient, a morphological shift should have occurred over time due to climate change. We tested this prediction, taking advantage of latitudinal and altitudinal variations within the Adelaide Geosyncline region, South Australia, historical herbarium specimens (n = 255) and field sampling (n = 274). Leaf width in the study taxon, Dodonaea viscosa subsp. angustissima, was negatively correlated with latitude regionally, and leaf area was negatively correlated with altitude locally. Analysis of herbarium specimens revealed a 2 mm decrease in leaf width (total range 1–9 mm) over 127 years across the region. The results are consistent with a morphological response to contemporary climate change. We conclude that leaf width is linked to maximum temperature regionally (latitude gradient) and leaf area to minimum temperature locally (altitude gradient). These data indicate a morphological shift consistent with a direct response to climate change and could inform provenance selection for restoration with further investigation of the genetic basis and adaptive significance of observed variation. PMID:22764114

  5. Polymer Morphological Change Induced by Terahertz Irradiation.

    PubMed

    Hoshina, Hiromichi; Suzuki, Hal; Otani, Chiko; Nagai, Masaya; Kawase, Keigo; Irizawa, Akinori; Isoyama, Goro

    2016-01-01

    As terahertz (THz) frequencies correspond to those of the intermolecular vibrational modes in a polymer, intense THz wave irradiation affects the macromolecular polymorph, which determines the polymer properties and functions. THz photon energy is quite low compared to the covalent bond energy; therefore, conformational changes can be induced "softly," without damaging the chemical structures. Here, we irradiate a poly(3-hydroxybutylate) (PHB) / chloroform solution during solvent casting crystallization using a THz wave generated by a free electron laser (FEL). Morphological observation shows the formation of micrometer-sized crystals in response to the THz wave irradiation. Further, a 10-20% increase in crystallinity is observed through analysis of the infrared (IR) absorption spectra. The peak power density of the irradiating THz wave is 40 MW/cm(2), which is significantly lower than the typical laser intensities used for material manipulation. We demonstrate for the first time that the THz wave effectively induces the intermolecular rearrangement of polymer macromolecules. PMID:27272984

  6. Changes in pancreatic morphology associated with aging

    PubMed Central

    Kreel, Louis; Sandin, Brenda

    1973-01-01

    Retrograde pancreatography has been carried out at necropsy in 120 cases and the results have been analysed in statistical detail. With increasing age, changes in pancreatic anatomy occur which must not be taken to indicate pathology. These changes are: (1) low or ptotic position of the pancreas so that the papilla of Vater is below the level of L3; (2) calcification of the splenic and superior mesenteric arteries which produce calcific densities around the pancreas; (3) increasing width of main pancreatic duct along its whole length at about 8% per decade; in the elderly, widths of 1 cm can occur in the main duct in the head of the pancreas without evidence of obstruction; (4) formation of ductular ectasia which affects mainly the interlobular ductules but also intralobular ductules; (5) some ectatic ducts reach the dimensions of cysts, ie, 1-2 cm in diameter. Other morphological changes which have been demonstrated and which may produce difficulties in radiological interpretation are: (a) narrowed ducts not due to stricture; (b) space-occupying lesions due to superior mesenteric artery, splenic artery, aorta, vertebral osteophytes, sympathetic ganglion, and lymph nodes; (c) metastases in the pancreas—these must be distinguished from primary pancreatic carcinoma. The implications of these findings for endoscopy and isotope pancreatic scanning will be mentioned. ImagesFig 3Fig 1Fig 4aFig 4bFig 5Fig 7 (a and b) PMID:4785285

  7. Polymer Morphological Change Induced by Terahertz Irradiation

    PubMed Central

    Hoshina, Hiromichi; Suzuki, Hal; Otani, Chiko; Nagai, Masaya; Kawase, Keigo; Irizawa, Akinori; Isoyama, Goro

    2016-01-01

    As terahertz (THz) frequencies correspond to those of the intermolecular vibrational modes in a polymer, intense THz wave irradiation affects the macromolecular polymorph, which determines the polymer properties and functions. THz photon energy is quite low compared to the covalent bond energy; therefore, conformational changes can be induced “softly,” without damaging the chemical structures. Here, we irradiate a poly(3-hydroxybutylate) (PHB) / chloroform solution during solvent casting crystallization using a THz wave generated by a free electron laser (FEL). Morphological observation shows the formation of micrometer-sized crystals in response to the THz wave irradiation. Further, a 10−20% increase in crystallinity is observed through analysis of the infrared (IR) absorption spectra. The peak power density of the irradiating THz wave is 40 MW/cm2, which is significantly lower than the typical laser intensities used for material manipulation. We demonstrate for the first time that the THz wave effectively induces the intermolecular rearrangement of polymer macromolecules. PMID:27272984

  8. Polymer Morphological Change Induced by Terahertz Irradiation

    NASA Astrophysics Data System (ADS)

    Hoshina, Hiromichi; Suzuki, Hal; Otani, Chiko; Nagai, Masaya; Kawase, Keigo; Irizawa, Akinori; Isoyama, Goro

    2016-06-01

    As terahertz (THz) frequencies correspond to those of the intermolecular vibrational modes in a polymer, intense THz wave irradiation affects the macromolecular polymorph, which determines the polymer properties and functions. THz photon energy is quite low compared to the covalent bond energy; therefore, conformational changes can be induced “softly,” without damaging the chemical structures. Here, we irradiate a poly(3-hydroxybutylate) (PHB) / chloroform solution during solvent casting crystallization using a THz wave generated by a free electron laser (FEL). Morphological observation shows the formation of micrometer-sized crystals in response to the THz wave irradiation. Further, a 10‑20% increase in crystallinity is observed through analysis of the infrared (IR) absorption spectra. The peak power density of the irradiating THz wave is 40 MW/cm2, which is significantly lower than the typical laser intensities used for material manipulation. We demonstrate for the first time that the THz wave effectively induces the intermolecular rearrangement of polymer macromolecules.

  9. TRIMETHYLTIN-INDUCED CHANGES IN GROSS MORPHOLOGY OF THE HIPPOCAMPUS

    EPA Science Inventory

    Acute exposure to trimethyltin (TMT) produces alterations in hippocampal morphology. The purpose of this study was to arrive at a simple method for quantitative assessment of the gross changes in morphology which could then be used as a correlate in studies of TMT toxicity. Adult...

  10. Recent and widespread rapid morphological change in rodents.

    PubMed

    Pergams, Oliver R W; Lawler, Joshua J

    2009-01-01

    In general, rapid morphological change in mammals has been infrequently documented. Examples that do exist are almost exclusively of rodents on islands. Such changes are usually attributed to selective release or founder events related to restricted gene flow in island settings. Here we document rapid morphological changes in rodents in 20 of 28 museum series collected on four continents, including 15 of 23 mainland sites. Approximately 17,000 measurements were taken of 1302 rodents. Trends included both increases and decreases in the 15 morphological traits measured, but slightly more trends were towards larger size. Generalized linear models indicated that changes in several of the individual morphological traits were associated with changes in human population density, current temperature gradients, and/or trends in temperature and precipitation. When we restricted these analyses to samples taken in the US (where data on human population trends were presumed to be more accurate), we found changes in two additional traits to be positively correlated with changes in human population density. Principle component analysis revealed general trends in cranial and external size, but these general trends were uncorrelated with climate or human population density. Our results indicate that over the last 100+ years, rapid morphological change in rodents has occurred quite frequently, and that these changes have taken place on the mainland as well as on islands. Our results also suggest that these changes may be driven, at least in part, by human population growth and climate change. PMID:19649284

  11. Changes in Bar Morphology in an Aggrading Gravel Bed River

    NASA Astrophysics Data System (ADS)

    Hodge, R. A.

    2014-12-01

    The River Wharfe, UK, is an aggrading gravel bed river, with frequent gravel bars. Management of the river system requires information about the rate and processes of change occurring to the gravel storage within the bars. From a scientific perspective, there are questions about how bar morphology changes as bars are deposited and eroded in this single thread system, about the extent to which flow conditions drive morphological change, and about the extent to which morphological changes can be predicted. Morphological changes of ten bars along the River Wharfe are reported between early 2012 and late 2014. The bars span a 6 km long length of river, downstream of the point where the river emerges from a confined valley. The bars range in length from 25 to 135 m. Bar grain size decreases downstream as a consequence of strong downstream fining. Bar morphology was surveyed using Terrestrial Laser Scanning at four time periods between early 2012 and late 2014. Each bar was surveyed from at least two scan positions, and georeferenced using a network of permanent survey markers. After initial processing to register the point clouds and remove vegetation, the change detection algorithm M3C2 was used to identify areas of significant volumetric change. The measured morphological changes between 2012 and 2013 indicate predominantly depositional changes on the bars, with an overall downstream decrease in the volume of change. However, there are local variations superimposed on this pattern. The mechanisms by which the bars change vary between bars, and include downstream progression of an avalanche face and gravel sheet infilling of local hollows. The measured changes are compared to flow data over the study period to identify the extent to which they are driven by flow.

  12. [TMJ morphological changes in abnormal occlusion].

    PubMed

    Volkov, S I; Bazhenov, D V; Semkin, V A; Bogdanov, A O

    2013-01-01

    TMJ dysfunction is one of the most common diseases among all disorders of the maxillofacial region. Any abnormality in synchrony or amplitude of motion of the TMJ results in the malposition of the articular disc. Researchers and clinicians were always interested in topographic anatomy of the TMJ. There is currently no consensus on matters relating to changes in anatomical features of the TMJ by occlusal disturbances. PMID:23715443

  13. Brainstem morphological changes in Alzheimer's disease.

    PubMed

    Lee, Ji Han; Ryan, John; Andreescu, Carmen; Aizenstein, Howard; Lim, Hyun Kook

    2015-05-01

    As brainstem nuclei are interconnected with several cortical structures and regulate several autonomic, cognitive, and behavioral functions, it might be important to place the brainstem within an important pathologic core in the progression of Alzheimer's disease (AD). Although there have been several postmortem studies reporting neuropathological alterations of the brainstem in AD, there has been no in-vivo structural neuroimaging study of the brainstem in the patients with AD. The aim of this study was to investigate differences in the brainstem volume and shape between patients with AD and elderly normal controls. Fifty AD patients (the Clinical Dementia Rating Scale ≥ 1) and 50 normal controls were recruited, and the brainstem volumes and deformations were compared between the AD and the controls. Patients with AD showed significant total volume [(mean ± SD) 21007 ± 1640 mm] reduction in the brainstem compared with the controls [(mean ± SD) 22530 ± 1750 mm] (P<0.001). In addition, AD patients showed significant brainstem deformations in the upper posterior brainstem corresponding to the midbrain compared with the healthy individuals (false discovery rate corrected P<0.05). This study is the first to explore brainstem volume change and deformations in AD. These structural changes in the midbrain areas might be at the core of the underlying neurobiological mechanisms of brainstem dysfunction with relevance to their various cognitive and behavioral symptoms such as memory impairment, sleep, and emotional disturbance in AD. However, further longitudinal studies might be needed to confirm these findings. PMID:25830491

  14. Ischemia detection from morphological QRS angle changes.

    PubMed

    Romero, Daniel; Martínez, Juan Pablo; Laguna, Pablo; Pueyo, Esther

    2016-07-01

    In this paper, an ischemia detector is presented based on the analysis of QRS-derived angles. The detector has been developed by modeling ischemic effects on the QRS angles as a gradual change with a certain transition time and assuming a Laplacian additive modeling error contaminating the angle series. Both standard and non-standard leads were used for analysis. Non-standard leads were obtained by applying the PCA technique over specific lead subsets to represent different potential locations of the ischemic zone. The performance of the proposed detector was tested over a population of 79 patients undergoing percutaneous coronary intervention in one of the major coronary arteries (LAD (n  =  25), RCA (n  =  16) and LCX (n  =  38)). The best detection performance, obtained for standard ECG leads, was achieved in the LAD group with values of sensitivity and specificity of [Formula: see text], [Formula: see text], followed by the RCA group with [Formula: see text], Sp  =  94.4 and the LCX group with [Formula: see text], [Formula: see text], notably outperforming detection based on the ST series in all cases, with the same detector structure. The timing of the detected ischemic events ranged from 30 s up to 150 s (mean  =  66.8 s) following the start of occlusion. We conclude that changes in the QRS angles can be used to detect acute myocardial ischemia. PMID:27243441

  15. Contractile dynamics change before morphological cues during florescence illumination

    PubMed Central

    Knoll, S. G.; Ahmed, W. W.; Saif, T. A.

    2015-01-01

    Illumination can have adverse effects on live cells. However, many experiments, e.g. traction force microscopy, rely on fluorescence microscopy. Current methods to assess undesired photo-induced cell changes rely on qualitative observation of changes in cell morphology. Here we utilize a quantitative technique to identify the effect of light on cell contractility prior to morphological changes. Fibroblasts were cultured on soft elastic hydrogels embedded with fluorescent beads. The adherent cells generated contractile forces that deform the substrate. Beads were used as fiducial markers to quantify the substrate deformation over time, which serves as a measure of cell force dynamics. We find that cells exposed to moderate fluorescence illumination (λ = 540–585 nm, I = 12.5 W/m2, duration = 60 s) exhibit rapid force relaxation. Strikingly, cells exhibit force relaxation after only 2 s of exposure, suggesting that photo-induced relaxation occurs nearly immediately. Evidence of photo-induced morphological changes were not observed for 15–30 min after illumination. Force relaxation and morphological changes were found to depend on wavelength and intensity of excitation light. This study demonstrates that changes in cell contractility reveal evidence of a photo-induced cell response long before any morphological cues. PMID:26691776

  16. Flight stability analysis under changes in insect morphology

    NASA Astrophysics Data System (ADS)

    Noest, Robert; Wang, Z. Jane

    2015-11-01

    Insect have an amazing ability to control their flight, being able to perform both fast aerial maneuvers and stable hovering. The insect's neural system has developed various mechanism by which it can control these flying feats, but we expect that insect morphology is equally important in facilitating the aerial control. We perform a computational study using a quasi-steady instantaneous flapping flight model which allows us to freely adapt the insect's morphological parameters. We picked a fruit fly as the basis for the body shape and wing motion, and study the effect of changes to the morphology for a range of wing stroke amplitudes. In each case we determine the periodic flight mode, with the period equal to a single wing beat, and do a Floquet stability analysis of the flight. To interpret our results we will compare the changed morphology to related insects. We discuss the implications of the insects location on the stability diagram.

  17. Simulation of morphological changes due to dam removal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this chapter, a brief review of numerical models and their applications for impact assessment of dam removal on sediment transport and morphological changes in alluvial rivers is given. As an example, a one-dimensional river flow and sediment transport model, CCHE1D, is applied to assess morpholo...

  18. Mitochondria Change Dynamics and Morphology during Grapevine Leaf Senescence

    PubMed Central

    Bodner, Martina; La Rocca, Nicoletta; De Michele, Roberto; Carimi, Francesco; Schiavo, Fiorella Lo; Zottini, Michela

    2014-01-01

    Leaf senescence is the last stage of development of an organ and is aimed to its ordered disassembly and nutrient reallocation. Whereas chlorophyll gradually degrades during senescence in leaves, mitochondria need to maintain active to sustain the energy demands of senescing cells. Here we analysed the motility and morphology of mitochondria in different stages of senescence in leaves of grapevine (Vitis vinifera), by stably expressing a GFP (green fluorescent protein) reporter targeted to these organelles. Results show that mitochondria were less dynamic and markedly changed morphology during senescence, passing from the elongated, branched structures found in mature leaves to enlarged and sparse organelles in senescent leaves. Progression of senescence in leaves was not synchronous, since changes in mitochondria from stomata were delayed. Mitochondrial morphology was also analysed in grapevine cell cultures. Mitochondria from cells at the end of their growth curve resembled those from senescing leaves, suggesting that cell cultures might represent a useful model system for senescence. Additionally, senescence-associated mitochondrial changes were observed in plants treated with high concentrations of cytokinins. Overall, morphology and dynamics of mitochondria might represent a reliable senescence marker for plant cells. PMID:25009991

  19. Morphological change in machines accelerates the evolution of robust behavior

    PubMed Central

    Bongard, Josh

    2011-01-01

    Most animals exhibit significant neurological and morphological change throughout their lifetime. No robots to date, however, grow new morphological structure while behaving. This is due to technological limitations but also because it is unclear that morphological change provides a benefit to the acquisition of robust behavior in machines. Here I show that in evolving populations of simulated robots, if robots grow from anguilliform into legged robots during their lifetime in the early stages of evolution, and the anguilliform body plan is gradually lost during later stages of evolution, gaits are evolved for the final, legged form of the robot more rapidly—and the evolved gaits are more robust—compared to evolving populations of legged robots that do not transition through the anguilliform body plan. This suggests that morphological change, as well as the evolution of development, are two important processes that improve the automatic generation of robust behaviors for machines. It also provides an experimental platform for investigating the relationship between the evolution of development and robust behavior in biological organisms. PMID:21220304

  20. Morphologic Changes in Autonomic Nerves in Diabetic Autonomic Neuropathy.

    PubMed

    Jin, Heung Yong; Baek, Hong Sun; Park, Tae Sun

    2015-12-01

    Diabetic neuropathy is one of the major complications of diabetes, and it increases morbidity and mortality in patients with both type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). Because the autonomic nervous system, for example, parasympathetic axons, has a diffuse and wide distribution, we do not know the morphological changes that occur in autonomic neural control and their exact mechanisms in diabetic patients with diabetic autonomic neuropathy (DAN). Although the prevalence of sympathetic and parasympathetic neuropathy is similar in T1DM versus T2DM patients, sympathetic nerve function correlates with parasympathetic neuropathy only in T1DM patients. The explanation for these discrepancies might be that parasympathetic nerve function was more severely affected among T2DM patients. As parasympathetic nerve damage seems to be more advanced than sympathetic nerve damage, it might be that parasympathetic neuropathy precedes sympathetic neuropathy in T2DM, which was Ewing's concept. This could be explained by the intrinsic morphologic difference. Therefore, the morphological changes in the sympathetic and parasympathetic nerves of involved organs in T1DM and T2DM patients who have DAN should be evaluated. In this review, evaluation methods for morphological changes in the epidermal nerves of skin, and the intrinsic nerves of the stomach will be discussed. PMID:26706915

  1. Single-cell resolution of morphological changes in hemogenic endothelium.

    PubMed

    Bos, Frank L; Hawkins, John S; Zovein, Ann C

    2015-08-01

    Endothelial-to-hematopoietic transition (EHT) occurs within a population of hemogenic endothelial cells during embryogenesis, and leads to the formation of the adult hematopoietic system. Currently, the prospective identification of specific endothelial cells that will undergo EHT, and the cellular events enabling this transition, are not known. We set out to define precisely the morphological events of EHT, and to correlate cellular morphology with the expression of the transcription factors RUNX1 and SOX17. A novel strategy was developed to allow for correlation of immunofluorescence data with the ultrastructural resolution of scanning electron microscopy. The approach can identify single endothelial cells undergoing EHT, as identified by the ratio of RUNX1 to SOX17 immunofluorescence levels, and the morphological changes associated with the transition. Furthermore, this work details a new technical resource that is widely applicable for correlative analyses of single cells in their native tissue environments. PMID:26243871

  2. Proliferative and morphologic changes in rat colon following bypass surgery.

    PubMed Central

    Barkla, D. H.; Tutton, P. J.

    1985-01-01

    In this study the proliferative and morphologic changes that occur in the colon of normal and dimethylhydrazine-treated rats following surgical bypass of the middle third of the colon are reported. Proliferative changes were measured by estimating accumulated mitotic indexes following vinblastine treatment and morphologic changes were observed with the use of light microscopy and scanning electron microscopy. Data were collected on Days 0, 7, 14, 30, and 72 after surgery. The results show that surgical bypass produces contrasting effects in the segments proximal to and distal to the suture line. In the proximal segment there was morphologic evidence of hyperplasia, although proliferative activity was unchanged except for an increase at 7 days in normal rats. In the distal segment there was a long-lived increase in the mitotic index, although morphologic changes were not seen. The results for DMH-treated rats were similar to those in normal rats. Groups of isolated dysplastic epithelial cells were often seen in the submucosa adjacent to sutures up to 72 days after surgery. Increased lymphoid infiltration was seen in segments proximal to but not distal to the suture line. It is hypothesized that the different responses of the proximal and distal segments may be related to the different embryologic origins of those segments. It is also hypothesized that the seeding of the submucosa with epithelial cells during suturing may be a factor in tumor recurrence. Images Figure 19 Figure 20 Figure 21 Figure 22 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 PMID:4014432

  3. Measurement of red blood cell mechanics during morphological changes

    NASA Astrophysics Data System (ADS)

    Popescu, Gabriel; Park, Yongkeun; Best, Catherine; Dasari, Ramachandra; Feld, Michael; Kuriabova, Tatiana; Henle, Mark; Levine, Alex

    2010-03-01

    The human red blood cell (RBC) membrane, a fluid lipid bilayer tethered to an elastic 2D spectrin network, provides the principal control of the cell's morphology and mechanics. These properties, in turn, influence the ability of RBCs to transport oxygen in circulation. Current mechanical measurements of RBCs rely on external loads. Here we apply a Noncontact optical interferometric technique to quantify the thermal fluctuations of RBC membranes with 3 nm accuracy over a broad range of spatial and temporal frequencies. Combining this technique with a new mathematical model describing RBC membrane undulations, we measure the mechanical changes of RBCs as they undergo a transition from the normal discoid shape to the abnormal echinocyte and spherical shapes. These measurements indicate that, coincident with this morphological transition, there is a significant increase in the membrane's shear and bending moduli. This mechanical transition can alter cell circulation and impede oxygen delivery.

  4. Seasonal activity and morphological changes in martian gullies

    USGS Publications Warehouse

    Dundas, Colin M.; Diniega, Serina; Hansen, Candice J.; Byrne, Shane; McEwen, Alfred S.

    2012-01-01

    Recent studies of martian dune and non-dune gullies have suggested a seasonal control on present-day gully activity. The timing of current gully activity, especially activity involving the formation or modification of channels (which commonly have been taken as evidence of fluvial processes), has important implications regarding likely gully formation processes and necessary environmental conditions. In this study, we describe the results of frequent meter-scale monitoring of several active gully sites by the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter (MRO). The aim is to better assess the scope and nature of current morphological changes and to provide improved constraints on timing of gully activity on both dune and non-dune slopes. Our observations indicate that (1) gully formation on Mars is ongoing today and (2) the most significant morphological changes are strongly associated with seasonal frost and defrosting activity. Observed changes include formation of all major components of typical gully landforms, although we have not observed alcove formation in coherent bedrock. These results reduce the need to invoke recent climate change or present-day groundwater seepage to explain the many martian gullies with pristine appearance.

  5. Hypersalinity drives physiological and morphological changes in Limia perugiae (Poeciliidae).

    PubMed

    Weaver, Pablo F; Tello, Oscar; Krieger, Jonathan; Marmolejo, Arlen; Weaver, Kathleen F; Garcia, Jerome V; Cruz, Alexander

    2016-01-01

    A fundamental question in biology is how an organism's morphology and physiology are shaped by its environment. Here, we evaluate the effects of a hypersaline environment on the morphology and physiology of a population of livebearing fish in the genus Limia (Poeciliidae). We sampled from two populations of Limia perugiae (one freshwater and one hypersaline) in the southwest Dominican Republic. We evaluated relative abundance of osmoregulatory proteins using western blot analyses and used a geometric morphometric approach to evaluate fine-scale changes to size and shape. Our data show that gill tissue isolated from hypersaline fish contained approximately two and a half times higher expression of Na(+)/K(+) ATPase proteins. We also show evidence for mitochondrial changes within the gills, with eight times more complex I and four times higher expression of ATP synthase within the gill tissue from the hypersaline population. The energetic consequences to Limia living in saline and hypersaline environments may be a driver for phenotypic diversity, reducing the overall body size and changing the relative size and shape of the head, as well as impeding the growth of secondary sex features among the males. PMID:27402966

  6. [Morphological changes in esophageal mucosa in children with overweight].

    PubMed

    Dubrovskaia, M I; Tertychnyĭ, A S; Mukhina, Iu G; Volodina, I I; Mamchenko, S I

    2010-01-01

    In present work we studied the morphological features of the esophageal mucosa in 63 children with endoscopic diagnosis of the distal esophagitis having overweight and normal weight of a body. The biopsies were taken at level of 3 cm above a Z-line and at level of 1 cm above a Z-line. Dystrophic and dysregenerative changes were revealed at the majority of children and half of children had inflammatory changes of the esophageal mucosa regardless of weight of a body. These changes are more pronounced at level of 1 cm above a Z-line, their occurrence decreases with a distance from low esophageal sphincter. We used the pathology score system for assess the esophageal biopsies. According our scale we obtained following results: at level of 1 cm above Z-lines at 95% of children had the normal, minimum or mild features of esophagitis regardless of weight of a body. Morphological evidence of a reflux esophagitis was diagnosed statistically more often at level of 1 cm above Z lines in comparison with level of 3 cm above Z-lines (p < 0.01) as among children with overweight of the body (78 and 43% accordingly), and among children with normal weight of the body (78 and 35% accordingly). The obtained data will be allowed to avoid hyperdiagnostics of esophageal lesions in children. PMID:20405708

  7. Hypersalinity drives physiological and morphological changes in Limia perugiae (Poeciliidae)

    PubMed Central

    Tello, Oscar; Krieger, Jonathan; Marmolejo, Arlen; Weaver, Kathleen F.; Garcia, Jerome V.; Cruz, Alexander

    2016-01-01

    ABSTRACT A fundamental question in biology is how an organism's morphology and physiology are shaped by its environment. Here, we evaluate the effects of a hypersaline environment on the morphology and physiology of a population of livebearing fish in the genus Limia (Poeciliidae). We sampled from two populations of Limia perugiae (one freshwater and one hypersaline) in the southwest Dominican Republic. We evaluated relative abundance of osmoregulatory proteins using western blot analyses and used a geometric morphometric approach to evaluate fine-scale changes to size and shape. Our data show that gill tissue isolated from hypersaline fish contained approximately two and a half times higher expression of Na+/K+ ATPase proteins. We also show evidence for mitochondrial changes within the gills, with eight times more complex I and four times higher expression of ATP synthase within the gill tissue from the hypersaline population. The energetic consequences to Limia living in saline and hypersaline environments may be a driver for phenotypic diversity, reducing the overall body size and changing the relative size and shape of the head, as well as impeding the growth of secondary sex features among the males. PMID:27402966

  8. Evaluations of mosquito age grading techniques based on morphological changes.

    PubMed

    Hugo, L E; Quick-Miles, S; Kay, B H; Ryan, P A

    2008-05-01

    Evaluations were made of the accuracy and practicality of mosquito age grading methods based on changes to mosquito morphology; including the Detinova ovarian tracheation, midgut meconium, Polovodova ovariole dilatation, ovarian injection, and daily growth line methods. Laboratory maintained Aedes vigilax (Skuse) and Culex annulirostris (Skuse) females of known chronological and physiological ages were used for these assessments. Application of the Detinova technique to laboratory reared Ae. vigilax females in a blinded trial enabled the successful identification of nulliparous and parous females in 83.7-89.8% of specimens. The success rate for identifying nulliparous females increased to 87.8-98.0% when observations of ovarian tracheation were combined with observations of the presence of midgut meconium. However, application of the Polovodova method only enabled 57.5% of nulliparous, 1-parous, 2-parous, and 3-parous Ae. vigilax females to be correctly classified, and ovarian injections were found to be unfeasible. Poor correlation was observed between the number of growth lines per phragma and the calendar age of laboratory reared Ae. vigilax females. In summary, morphological age grading methods that offer simple two-category predictions (ovarian tracheation and midgut meconium methods) were found to provide high-accuracy classifications, whereas methods that offer the separation of multiple age categories (ovariolar dilatation and growth line methods) were found to be extremely difficult and of low accuracy. The usefulness of the morphology-based methods is discussed in view of the availability of new mosquito age grading techniques based on cuticular hydrocarbon and gene transcription changes. PMID:18533427

  9. Dynamics of morphological changes for mitochondrial fission and fusion

    NASA Astrophysics Data System (ADS)

    Wang, Shiqi; Fu, Changliang; Zhang, Yan; Chen, Quan; Long, Mian

    2010-04-01

    Mitochondria experience continuous fusion and fission in a living cell, but their dynamics remains poorly quantified. Here a theoretical model was developed, upon a simplified population balance equation (PBE), to predict the morphological changes induced by mitochondrial fission and fusion. Assuming that both fission and fusion events are statistically independent, the survival probability of mitochondria staying in the fission or fusion state was formulated as an exponentially-decayed function with time, which depended on the time-dependent distribution of the mitochondrial volume and the fission and fusion rates. Parametric analysis was done for two typical volume distributions. One was Gamma distribution and the other was Gaussian distribution, derived from the measurements of volume distribution for individual mitochondria in a living cell and purified mitochondria in vitro. The predictions indicated that the survival probability strongly depended on morphological changes of individual mitochondria and was inversely correlated to the fission and fusion rates. This work provided a new insight into quantifying the mitochondrial dynamics via monitoring the evolution of the mitochondrial volume.

  10. Change in P wave morphology after convergent atrial fibrillation ablation.

    PubMed

    Shrestha, Suvash; Chen, On; Greene, Mary; John, Jinu Jacob; Greenberg, Yisachar; Yang, Felix

    2016-01-01

    Convergent atrial fibrillation ablation involves extensive epicardial as well as endocardial ablation of the left atrium. We examined whether it changes the morphology of the surface P wave. We reviewed electrocardiograms of 29 patients who underwent convergent ablation for atrial fibrillation. In leads V1, II and III, we measured P wave duration, area and amplitude before ablation, and at 1, 3 and 6 months from ablation. After ablation, there were no significant changes in P wave amplitude, area, or duration in leads II and III. There was a significant reduction in the area of the terminal negative deflection of the P wave in V1 from 0.38 mm(2) to 0.13 mm(2) (p = 0.03). There is also an acute increase in the amplitude and duration of the positive component of the P wave in V1 followed by a reduction in both by 6 months. Before ablation, 62.5% of the patients had biphasic P waves in V1. In 6 months, only 39.2% of them had biphasic P waves. Hybrid ablation causes a reduction of the terminal negative deflection of the P wave in V1 as well as temporal changes in the duration and amplitude of the positive component of the P wave in V1. This likely reflects the reduced electrical contribution of the posterior left atrium after ablation as well as anatomical and autonomic remodeling. Recognition of this altered sinus P wave morphology is useful in the diagnosis of atrial arrhythmias in this patient population. PMID:27485559

  11. Mackenzie River Delta morphological change based on Landsat time series

    NASA Astrophysics Data System (ADS)

    Vesakoski, Jenni-Mari; Alho, Petteri; Gustafsson, David; Arheimer, Berit; Isberg, Kristina

    2015-04-01

    Arctic rivers are sensitive and yet quite unexplored river systems to which the climate change will impact on. Research has not focused in detail on the fluvial geomorphology of the Arctic rivers mainly due to the remoteness and wideness of the watersheds, problems with data availability and difficult accessibility. Nowadays wide collaborative spatial databases in hydrology as well as extensive remote sensing datasets over the Arctic are available and they enable improved investigation of the Arctic watersheds. Thereby, it is also important to develop and improve methods that enable detecting the fluvio-morphological processes based on the available data. Furthermore, it is essential to reconstruct and improve the understanding of the past fluvial processes in order to better understand prevailing and future fluvial processes. In this study we sum up the fluvial geomorphological change in the Mackenzie River Delta during the last ~30 years. The Mackenzie River Delta (~13 000 km2) is situated in the North Western Territories, Canada where the Mackenzie River enters to the Beaufort Sea, Arctic Ocean near the city of Inuvik. Mackenzie River Delta is lake-rich, productive ecosystem and ecologically sensitive environment. Research objective is achieved through two sub-objectives: 1) Interpretation of the deltaic river channel planform change by applying Landsat time series. 2) Definition of the variables that have impacted the most on detected changes by applying statistics and long hydrological time series derived from Arctic-HYPE model (HYdrologic Predictions for Environment) developed by Swedish Meteorological and Hydrological Institute. According to our satellite interpretation, field observations and statistical analyses, notable spatio-temporal changes have occurred in the morphology of the river channel and delta during the past 30 years. For example, the channels have been developing in braiding and sinuosity. In addition, various linkages between the studied

  12. Incorporating climate change and morphological uncertainty into coastal change hazard assessments

    USGS Publications Warehouse

    Baron, Heather M.; Ruggiero, Peter; Wood, Nathan J.; Harris, Erica L.; Allan, Jonathan; Komar, Paul D.; Corcoran, Patrick

    2015-01-01

    Documented and forecasted trends in rising sea levels and changes in storminess patterns have the potential to increase the frequency, magnitude, and spatial extent of coastal change hazards. To develop realistic adaptation strategies, coastal planners need information about coastal change hazards that recognizes the dynamic temporal and spatial scales of beach morphology, the climate controls on coastal change hazards, and the uncertainties surrounding the drivers and impacts of climate change. We present a probabilistic approach for quantifying and mapping coastal change hazards that incorporates the uncertainty associated with both climate change and morphological variability. To demonstrate the approach, coastal change hazard zones of arbitrary confidence levels are developed for the Tillamook County (State of Oregon, USA) coastline using a suite of simple models and a range of possible climate futures related to wave climate, sea-level rise projections, and the frequency of major El Niño events. Extreme total water levels are more influenced by wave height variability, whereas the magnitude of erosion is more influenced by sea-level rise scenarios. Morphological variability has a stronger influence on the width of coastal hazard zones than the uncertainty associated with the range of climate change scenarios.

  13. Selected morphological changes in Artemia franciscana after ionizing radiation exposure.

    PubMed

    Dvořák, P; Zd'árský, M; Beňová, K; Spalek, M

    2012-08-01

    Nauplii of Artemia franciscana were irradiated by the doses of 0.25, 0.5, 1.0, and 2.5 kGy (60)Co. Dimensions of the body length, body width, intestine width, intestine epithelium width, and intestine lumen width, as well as the mutual ratios of dimensions were determined in 126 specimens. Ratios of the body length/body width (3.98, 3.60, 3.59, and 3.45 vs. 4.13 of control group), and ratios of the intestine epithelium width/intestine lumen width (0.64, 0.52, 0.51, and 0.45 vs. 0.85 of control group), according to the doses, were the most important parameters of evaluation of dependence of morphological changes on radiation doses. PMID:22673764

  14. Change in surface morphology of polytetrafluoroethylene by reactive ion etching

    NASA Astrophysics Data System (ADS)

    Takahashi, Tomohiro; Hirano, Yuki; Takasawa, Yuya; Gowa, Tomoko; Fukutake, Naoyuki; Oshima, Akihiro; Tagawa, Seiichi; Washio, Masakazu

    2011-02-01

    Polytetrafluoroethylene (PTFE) was exposed to Ar, CF 4, N 2 and O 2 plasmas using a reactive ion etching facility. After the exposure, the change in the surface morphology of PTFE was examined and characterization studies were performed for the etching rate, surface roughness, radical yields, chemical structures, water repellency and so on. The etching rates of Ar, CF 4, N 2 and O 2 plasmas were 0.58, 7.2, 4.4 and 17 μm/h, respectively. It was observed that needle-like nano-fiber structures on the surface were irregularly fabricated by the CF 4 plasma. In addition, when the water repellency of exposed samples was evaluated by contact angle, they showed super-hydrophobic properties: contact angle over 150°.

  15. Secular Change in Morphological Pelvic Traits used for Sex Estimation.

    PubMed

    Klales, Alexandra R

    2016-03-01

    This research evaluates secular change in Phenice's (Am J Phys Anthropol, 30, 1969 and 297) three morphological traits of the pubis, as described by Klales et al. (Am J Phys Anthropol, 149, 2012 and 104): medial aspect of the ischio-pubic ramus, subpubic contour, and ventral arc. Ordinal scores were collected for these traits and compared between a sample of innominates from the historical Hamann-Todd Collection (n = 170) and modern Bass Donated Collection (n = 129). Using the Freeman-Halton test, significant differences between temporal sample score frequencies were found for all traits in females and for the subpubic contour and ventral arc in males. Despite these findings, classification accuracy using logistic regression between the temporal periods remained low (68.7%). These results suggest that secular changes in trait expression are occurring; however, sex estimation methods using these traits and created with historical samples are still applicable to modern forensic cases. In fact, the secular changes occurring in these traits contribute to better classification accuracy between sexes in modern populations. PMID:27404602

  16. Exploring Morphological Process Indicators in Regional Patterns of Shoreline Change

    NASA Astrophysics Data System (ADS)

    Lazarus, E. D.; List, J. H.; Murray, A. B.

    2007-12-01

    Beach morphology changes over a continuum of time and spatial scales, from ephemeral patterns (100 - 102 m alongshore) such as cusps and scarps that develop and dissipate over days to weeks, to persistent plan-view bumps in the shoreline (103 - 105 m), such as promontories, embayments, and capes, that tend to erode and accrete over years to millennia. Localized sediment cycling at smaller scales is strongly associated with cross-shore transport, while theoretical and data-analysis findings attribute large-scale shoreline evolution to alongshore sediment-transport processes; deep-water incident waves interacting with a sediment- covered shoreface are predicted to set up gradients in alongshore sediment transport that, depending on their approach angle, can exaggerate or smooth away shoreline perturbations. Patterns of alongshore sediment flux thus produce a correlation between shoreline-position change and shoreline curvature that depends on whether high- or low-angle waves dominated the wave climate over a given time span. Recent work on the northern North Carolina Outer Banks using lidar surveys to measure shoreline position shows a significant negative correlation, strongest at long time (decadal) and spatial (km) scales, between position change and shoreline curvature, suggestive of diffusion driven by a low-angle-dominated regional wave climate over the last decade. Correlations between position change and shoreline curvature, however, can arise from processes other than gradients in alongshore transport strictly related to shoreline curvature. Near the towns of Kitty Hawk, Kill Devil Hills, and Nags Head, a series of oblique sandy bars and gravel-floored troughs ~1 km wide define the nearshore bathymetry for approximately 5 - 8 km alongshore. Wave propagation over these features likely causes alongshore variations in breaking wave height and angle that affect alongshore sediment transport and patterns of shoreline change. From annual lidar surveys and vehicle

  17. Mathematical morphologic analysis of aging-related epidermal changes.

    PubMed

    Moragas, A; Castells, C; Sans, M

    1993-04-01

    Fractographic techniques based on mathematical morphology were used to study aging-related epidermal changes in abdominal skin samples obtained from 96 autopsy cases. Three linear roughness indices were evaluated for the rete peg profile and the shrinkage effect on the basal layer and interface between the granular and horny layers. Elderly subjects had a 36.3% decrease in rete peg-related roughness index when compared with younger subjects. This roughness index has been corrected, with shrinkage due to skin elasticity taken into account. For females, fitting of a logistic decay function yielded a curve with right and left asymptotes and a steeper descent between 40 and 60 years. Half value time--i.e., the time when half rete peg profile flattening occurred--was 46.8 years. In contrast, males showed almost monotonical decay. Epidermal thickness measured between rete pegs showed the same exponential decline for both sexes, with values from 22.6 to 11.4 microns. Skin shrinkage in elderly subjects decreased 22% in superficial layers and only 6% in the lower epidermis. In both cases shrinkage had a linear relation with age, and no sex differences were found. PMID:8318130

  18. Morphological determinants of peripheral lung mechanical changes induced by capsaicin.

    PubMed

    Dolhnikoff, M; Sakae, R S; Saldiva, P H; Martins, M A

    1997-04-01

    We studied the morphological elements associated with airway and pulmonary tissue responses to capsaicin in mechanically ventilated guinea pigs. Lungs were excised and frozen in liquid nitrogen 3 and 20 min after capsaicin infusion (1 or 100 micrograms/kg i.v.). Using image analysis, we obtained contraction index (CI) and peribronchial edema area (CUFF) for both central (C) and peripheral airways (P). We also assessed alveolar size (mean linear intercepts, Lm) and tissue distortion (standard deviation of the number of intercepts, SDI). Multiple regression analysis showed significant associations between pulmonary tissue resistance (Rti) and CUFFP (p < 0.001); pulmonary dynamic elastance and SDI (p = 0.002); and airway resistance and CUFFC (p < 0.0001). Our results suggest that increases in Rti observed in guinea pigs after capsaicin infusion are primarily dependent on changes in the small airways, mainly peribronchiolar edema; the increase in lung elastance is related to distortion of parenchymal tissues; and large airway edema contributes significantly to airway resistance. PMID:9178377

  19. Thermally induced phase transitions and morphological changes in organoclays.

    PubMed

    Gelfer, M; Burger, C; Fadeev, A; Sics, I; Chu, B; Hsiao, B S; Heintz, A; Kojo, K; Hsu, S L; Si, M; Rafailovich, M

    2004-04-27

    Thermal transitions and morphological changes in Cloisite organoclays were investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, and in situ simultaneous small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) over the temperature range of 30-260 degrees C. On the basis of DSC and FTIR results, the surfactant component in organoclays was found to undergo a melting-like order-disorder transition between 35 and 50 degrees C. The transition temperatures of the DSC peaks (Ttr) in the organoclays varied slightly with the surfactant content; however, they were significantly lower than the melting temperature of the free surfactant (dimethyldihydrotallowammonium chloride; Tm = 70 degrees C). FTIR results indicated that within the vicinity of Ttr, the gauche content increased significantly in the conformation of surfactant molecules, while WAXD results did not show any change in three-dimensional ordering. Multiple scattering peaks were observed in SAXS profiles. In the SAXS data acquired below Ttr, the second scattering peak was found to occur at an angle lower than twice that of the first peak position (i.e., nonequidistant scattering maxima). In the data acquired above Ttr, the second peak was found to shift toward the equidistant position (the most drastic shift was seen in the system with the highest surfactant content). Using a novel SAXS modeling technique, we suggest that the appearance of nonequidistant SAXS maxima could result from a bimodal layer thickness distribution of the organic layers in organoclays. The occurrence of the equidistant scattering profile above Ttr could be explained by the conversion of the bimodal distribution to the unimodal distribution, indicating a redistribution of the surfactant that is nonbounded to the clay surface. At temperatures above 190 degrees C, the scattering maxima gradually broadened and became nonequidistant again but

  20. Measuring Complexity of Mouse Brain Morphological Changes Using GeoEntropy

    NASA Astrophysics Data System (ADS)

    El-fiqi, Heba Z.; Pham, Tuan D.; Hattori, Haroldo T.; Crane, Denis I.

    2010-01-01

    Given the current emphasis on research into human neurodegenerative diseases, an effective computing approach for the analysis of complex brain morphological changes would represent a significant technological innovation. The availability of mouse models of such disorders provides an experimental system to test novel approaches to brain image analysis. Here we utilize a mouse model of a neurodegenerative disorder to model changes to cerebellar morphology during the postnatal period, and have applied the GeoEntropy algorithm to measure the complexity of morphological changes.

  1. Effect of culture conditions on morphological changes of Helicobacter pylori.

    PubMed

    Tominaga, K; Hamasaki, N; Watanabe, T; Uchida, T; Fujiwara, Y; Takaishi, O; Higuchi, K; Arakawa, T; Ishii, E; Kobayashi, K; Yano, I; Kuroki, T

    1999-01-01

    The morphological conversion of Helicobacter pylori from the spiral form to the coccoid form may be the expression of a transitory adaptation to an unsuitable environment. The mechanism(s) of this conversion are not clear. In this study, we examined whether the morphological conversion of H. pylori is affected by various culture conditions, such as oxygen concentration, pH, temperature, or the presence of beta-cyclodextrin. H. pylori (NTCC11916) was cultured on Brucella agar, followed by culture in Brucella broth containing 1% agar under several conditions. Morphological conversion of individual H. pylori on the agar plate was investigated with time after incubation under phase contrast microscopy. When H. pylori was inoculated in Brucella broth containing beta-cyclodextrin, the spiral form of the organism was observed even after 6 days of incubation under standard culture conditions: 37 degrees C, pH 7, and microaerobic atmosphere (5% O2/10% CO2/85% N2) (control). The morphological conversion of H. pylori was completed on day 3 in an aerobic atmosphere (20% O2 supply) and on day 2 in an undermicroaerobic atmosphere (<0.1% O2). Its complete morphological conversion was observed at pH 8 on day 5 and at pH 4 on day 6. All of the H. pylori (100%) incubated at 20 degrees or 42 degrees C had converted from the bacillary to the coccoid form on day 4. Conditioned medium without beta-cyclodextrin caused complete conversion on day 5. These results suggest that oxygen concentration, pH, temperature, and beta-cyclodextrin may be related to the H. pylori morphological conversion from the bacillary to the coccoid form. PMID:10616762

  2. The morphological changes of Ascaris lumbricoides ova in sewage sludge water treated by gamma irradiation

    NASA Astrophysics Data System (ADS)

    Shamma, M.; Al-Adawi, M. A.

    2002-10-01

    Untreated wastewater sampled from Damascus sewage water treatment plant containing nematode Ascaris lumbricoides ova were treated using gamma irradiation (doses between 1.5 and 8 kGy), immediately after irradiation the morphological and developmental status of eggs was examined microscopically. Major morphological changes of the contents of the eggs were detected. These eggs were incubated for 8 weeks, after this period no larvae "inside the eggs" were observed. Thus the morphological changes can be used as a viable parameter.

  3. Gold-plated silver nanoparticles engineered for sensitive plasmonic detection amplified by morphological changes.

    PubMed

    Hobbs, Krysten; Cathcart, Nicole; Kitaev, Vladimir

    2016-07-28

    Gold-plated silver nanoparticles have been developed to undergo morphological changes that enhance the surface plasmon resonance (SPR) sensing response. These morphological changes were realized through thin-frame gold plating that both reinforces the nanoparticle edges and enables partial silver etching upon exposure to several biological molecules, including thiols and amines. PMID:27418122

  4. Analysis of the Topographic and Morphological Characteristics of Chang'e 3 Landing Site

    NASA Astrophysics Data System (ADS)

    Li, H.; Li, C.; Mu, L.; Zou, X.; Liu, J.; Ren, X.; Zeng, X.

    2014-12-01

    Chang'e 3 (CE-3) landed at (19.51ºW, 44.12ºN) in northwestern Mare Imbrium at 13:11 (GMT) on December 14, 2013, as China's first mission to soft land on the Moon and explore the lunar surface. Employing CE-2 and CE-3 high-resolution topographic and imagery data, we analyze the background area (45 km × 70 km) of the landing site and the topographic, morphological, and lunar dust characteristics of the landing area. With CE-3 landing camera (LCAM) images, we extract information on the distribution of topographic elements, craters, boulders within 4 km × 4 km area of the landing site. In addition, we also analyze the effect of CE-3 engine on the distribution of lunar dust near the landing site. An area of 60 m × 135 m is affected with redistribution of dust and changed space weathering effect.

  5. Quantitative analysis of radiation-induced changes in sperm morphology.

    PubMed

    Young, I T; Gledhill, B L; Lake, S; Wyrobek, A J

    1982-09-01

    When developing spermatogenic cells are exposed to radiation, chemical carcinogens or mutagens, the transformation in the morphology of the mature sperm can be used to determine the severity of the exposure. In this study five groups of mice with three mice per group received testicular doses of X irradiation at dosage levels ranging from 0 rad to 120 rad. A random sample of 100 mature sperm per mouse was analyzed five weeks later for the quantitative morphologic transformation as a function of dosage level. The cells were stained with gallocyanin chrome alum (GCA) so that only the DNA in the sperm head was visible. The ACUity quantitative microscopy system at Lawrence Livermore National Laboratory was used to scan the sperm at a sampling density of 16 points per linear micrometer and with 256 brightness levels per point. The contour of each cell was extracted using conventional thresholding techniques on the high-contrast images. For each contour a variety of shape features was then computed to characterize the morphology of that cell. Using the control group and the distribution of their shape features to establish the variability of a normal sperm population, the 95% limits on normal morphology were established. Using only four shape features, a doubling dose of approximately 39 rad was determined. That is, at 39 rad exposure the percentage of abnormal cells was twice that occurring in the control population. This compared to a doubling dose of approximately 70 rad obtained from a concurrent visual procedure. PMID:6184000

  6. Menstrual cycle-related changes in amygdala morphology are associated with changes in stress sensitivity.

    PubMed

    Ossewaarde, Lindsey; van Wingen, Guido A; Rijpkema, Mark; Bäckström, Torbjörn; Hermans, Erno J; Fernández, Guillén

    2013-05-01

    Premenstrual increases in negative mood are thought to arise from changes in gonadal hormone levels, presumably by influencing mood regulation and stress sensitivity. The amygdala plays a major role in this context, and animal studies suggest that gonadal hormones influence its morphology. Here, we investigated whether amygdala morphology changes over the menstrual cycle and whether this change explains differences in stress sensitivity. Twenty-eight young healthy women were investigated once during the premenstrual phase and once during the late follicular phase. T1-weighted anatomical images of the brain were acquired using magnetic resonance imaging and analyzed with optimized voxel-based morphometry. To measure mood regulation and stress sensitivity, negative affect was assessed after viewing strongly aversive as well as neutral movie clips. Our results show increased gray matter volume in the dorsal part of the left amygdala during the premenstrual phase when compared with the late follicular phase. This volume increase was positively correlated with the premenstrual increase in stress-induced negative affect. This is the first study showing structural plasticity of the amygdala in humans at the macroscopic level that is associated with both endogenous gonadal hormone fluctuations and stress sensitivity. These results correspond with animal findings of gonadal hormone-mediated neural plasticity in the amygdala and have implications for understanding the pathogenesis of specific mood disorders associated with hormonal fluctuations. PMID:22162177

  7. Dynamic changes in PDMS surface morphology in femtosecond laser treatment.

    PubMed

    Moon, Heh-Young; Sidhu, Mehra S; Lee, Heung Soon; Jeoung, Sae Chae

    2015-07-27

    We have investigated the effect of the dynamics of crater size on the poly(dimethylsiloxane) (PDMS) surface morphology in fs-laser micro-processing. PDMS surface was processed with varying both inter-pulse interval and inter-spot distance between successive laser pulses. With keeping the interval of 5 ms crater shape is round even if the spot is overlapped in space. But decreasing the interval to 0.02 ms the shape of the crater is no longer round. Decreasing the inter-distance between the craters results in roughened surface morphology even at time intervals of 5 ms. Temporal dependence of single-shot fs-laser induced crater size was measured as a function of time delay. Within 0.1 ms after pulse irradiation with a fluence of 4.8 J/cm2 on PDMS surface the crater size has reached to its maximum values and then decreased with a time constant of about 0.3 ms. The surface morphology after fs-laser pulse irradiation is strongly dependent on not only inter-spot distance between successive laser pulse but also their inter-pulse intervals. By proposing a theoretical model on their dynamic features, we will try to explain the current observation in quantitatively. PMID:26367645

  8. Lunar Mare Dome Identification and Morphologic Properties Analysis Using Chang'E-2 Lunar Data

    NASA Astrophysics Data System (ADS)

    Zeng, Xingguo; Mu, Lingli; Li, Chunlai; Liu, Jianjun; Ren, Xin; Wang, Yuanyuan

    2016-04-01

    Identify the lunar mare dome and study the morphologic properties to know more knowledge about the structure will enhance the study of lunar volcanism. Traditionally, most lunar domes are identified by the scientists from exploring the images or topographic maps of the lunar surface with manual method, which already found out a bunch of lunar domes in specific local areas. For the purpose of getting more knowledge about global lunar dome, it is necessary to identify the lunar dome from the global lunar mare. However, it is hard to find new lunar domes from the global lunar mare only with manual method, since in that case, the large volume lunar data is needed and such work is too time consumed, so that, there are few researchers who have indentified and study the properties of the lunar dome from the perspective of lunar global scale. To solve the problem mentioned above, in this approach , CE-2 DEM, DOM data in 7m resolution were used in the detection and morphologic analysis of the lunar domes and a dome detection method based on topographic characteristics were developed.We firstly designed a method considering the morphologic characteristics to identify the lunar dome with Chang'E2(CE-2) lunar global data, after that, the initial identified result with properties is analyzed, and finally, by integrating the result with lunar domes already found by former researchers, we made some maps about the spatial distribution of the global lunar mare dome. With the CE-2 data covering the former lunar domes and the new found lunar domes, we surveyed and calculated some morphologic properties, and found that, lunar domes are circular or eclipse shaped, obviously different from background in topography,which has a average diameter between 3-25km, circular degree less than 1.54, with a average slope less than 10°, average height less than 650m and diameter/height less than 0.065. Almost all of the lunar domes are located in the extent of 58°N~54°S,167°W~180°E,and nearly

  9. Changes in portlandite morphology with solvent composition: Atomistic simulations and experiment

    SciTech Connect

    Galmarini, Sandra Aimable, Anne; Ruffray, Nicolas; Bowen, Paul

    2011-12-15

    Experimental work has been done to determine changes in the particle shape of portlandite grown in the presence of different ions. To quantify the experimentally observed changes in morphology a new analysis tool was developed, allowing the calculation of the relative surface energies of the crystal facets. The observed morphology in the presence of chlorides and nitrates was facetted particles of a similar shape, the addition of sulfates leads to hexagonal platelet morphology and the addition of silicates leads to the formation of large irregular aggregates. In addition to the experimental work, the surfaces of portlandite were studied with atomistic simulation techniques. The empirical force field used has first been validated. The equilibrium morphology of portlandite in vacuum and in water was then calculated. The results indicate that the presence of water stabilizes the [20.3] surface and changes the morphology. This is consistent with the experimental observation of [20.3] surfaces.

  10. Simulation and control of morphological changes due to dam removal in the Sandy River, Oregon, USA

    NASA Astrophysics Data System (ADS)

    Ding, Y.; Altinakar, M. S.

    2015-03-01

    A one-dimensional channel evolution simulation model (CCHE1D) is applied to assess morphological changes in a reach of the Sandy River, Oregon, USA, due to the Marmot Dam removal in 2007. Sediment transport model parameters (e.g. sediment transport capacity, bed roughness coefficient) were calibrated using observed bed changes after the dam removal. The validated model is then applied to assess long-term morphological changes in response to a 10-year hydrograph selected from historical storm water records. The long-term assessment of sedimentation gives a reasonable prediction of morphological changes, expanding erosion in reservoir and growing deposition immediately downstream of the dam site. This prediction result can be used for managing and planning river sedimentation after dam removal. A simulation-based optimization model is also applied to determine the optimal sediment release rates during dam-removal that will minimize the morphological changes in the downstream reaches.

  11. Morphological and acrosomal changes of canine spermatozoa during epididymal transit

    PubMed Central

    2013-01-01

    Background During epididymal transit, functional and structural modifications leading to full maturation enable male gametes to reach, recognize and fertilize the oocytes. In dogs, little is known on the modifications of spermatozoa during the passage in the epididymis. The aim of this study was to describe the motility, morphology and acrosomal patterns of canine spermatozoa retrieved from the epididymis caput, corpus and cauda. Results After the dilution required for the collection of epididymal content, sperm motility was significantly higher (P <0.0001) in the cauda compared to corpus and caput. Proportions of spermatozoa with normal morphology were significantly higher in corpus (P =0.02) and cauda (P <0.0001) compared to caput. Overall morphological abnormalities of the head and neck/midpiece were similar in the three different epididymal regions. A significantly increased prevalence of tail defects, mainly represented by single bent tails, was observed in the corpus compared to caput (P <0.0001) and cauda (P =0.006). Numbers of immature sperm with cytoplasmic droplets decreased from the proximal to the distal region of the epididymis. Particularly, proximal cytoplasmic droplets were more frequently found in spermatozoa collected from the caput epididymis than in the corpus (P <0.0001) and in the cauda (P <0.0001), whereas the occurrence of distal cytoplasmic droplets was higher in the corpus than in the caput (P =0.0003) and in the cauda (P <0.05). Significantly higher proportions of spermatozoa with intact acrosomes were retrieved from the cauda epididymis than from the caput (P =0.03) and the corpus (P =0.008). This difference was mainly due to a lower proportion of spermatozoa with abnormal acrosomes (mainly swollen acrosomes) rather than with absent acrosomes. Conclusions Canine spermatozoa undergo several modifications in the epididymis. The acquisition of progressive motility, migration of the cytoplasmic droplet and acrosomal reshaping lead to mature

  12. Morphological changes in polycrystalline Fe after compression and release

    NASA Astrophysics Data System (ADS)

    Gunkelmann, Nina; Tramontina, Diego R.; Bringa, Eduardo M.; Urbassek, Herbert M.

    2015-02-01

    Despite a number of large-scale molecular dynamics simulations of shock compressed iron, the morphological properties of simulated recovered samples are still unexplored. Key questions remain open in this area, including the role of dislocation motion and deformation twinning in shear stress release. In this study, we present simulations of homogeneous uniaxial compression and recovery of large polycrystalline iron samples. Our results reveal significant recovery of the body-centered cubic grains with some deformation twinning driven by shear stress, in agreement with experimental results by Wang et al. [Sci. Rep. 3, 1086 (2013)]. The twin fraction agrees reasonably well with a semi-analytical model which assumes a critical shear stress for twinning. On reloading, twins disappear and the material reaches a very low strength value.

  13. Morphological changes of V-79 cells after equinatoxin II treatment.

    PubMed

    Batista, U; Jezernik, K

    1992-02-01

    Morphological observations on the V-79-379 A cells after treatment with equinatoxin II (EqT II), isolated from the sea anemone Actina equina L., and fetal calf serum (FCS) treated toxin were examined by transmission electron microscopy. Our results showed that the cells incubated with FCS treated EqT II were almost ultrastructurally unaltered. When the cells were treated with low concentrations of EqT II alone cell ultrastructure was altered with the evidence of numerous blebs and decreased microvilli number on the cell surface and appearance of numerous vesicles in the Golgi regions. High concentrations of EqT II caused disintegration of plasmalemma and intracellular membranes as well as degradation of cytosol. PMID:1348018

  14. Morphological Changes in Rat Vestibular System Following Weightlessness

    NASA Technical Reports Server (NTRS)

    Ross, Muriel D.

    1993-01-01

    Mammalian gravity receptors (maculas) are morphologically organized for weighted, parallel distributed processing of information. There are two basic circuits: 1) highly channeled, type I cell to calyx; and 2) distributed modifying, type II cells to calyces and processes. The latter circuit should be the more adaptable since it modifies final output. To test this hypothesis, rats were flown in microgravity for 9 days aboard a space shuttle and euthanized shortly after landing. Hair cells and ribbon synapses from maculas of 3 flight and 3 ground control rats were studied ultrastructurally in blocks of 50 serial sections. Synapses increased by approximately 41% in type I cells and by approximately 55% in type II cells in flight animals. There was a shift toward the spherular form of ribbon synapse in both types of hair cells in flight animals. Current findings tend to support the stated hypothesis and indicate that mature utricular hair cells retain synaptic plasticity, permitting adaptation to an altered gravitational environment.

  15. Morphological change of skin fibroblasts induced by UV Irradiation is involved in photoaging.

    PubMed

    Yamaba, Hiroyuki; Haba, Manami; Kunita, Mayumi; Sakaida, Tsutomu; Tanaka, Hiroshi; Yashiro, Youichi; Nakata, Satoru

    2016-08-01

    Human dermal fibroblasts (HDFs) are typically flattened or extensible shaped and play a critical role in the metabolism of extracellular matrix components. As the properties of fibroblasts in the dermis are considered to be influenced by their morphology, we investigated the morphological changes induced in fibroblasts by ultraviolet (UV) irradiation as well as the relationship between these changes and collagen metabolism. In this study, we showed that UVA exposure induced morphological changes and reduced collagen contents in HDFs. These morphological changes were accompanied a reduction in actin filaments and upregulation of the actin filament polymerization inhibitor, capping protein muscle Z-line ɑ1 (CAPZA1). External actin filament growth inhibitors also affected the shape of HDFs and reduced collagen levels. These results suggest that UVA exposure may inhibit the polymerization of actin filaments and induce morphological changes in skin fibroblasts. These morphological changes in fibroblasts may accelerate reductions in collagen synthesis. This mechanism may be one of the processes responsible for collagen reductions observed in photoaged skin. When natural materials that suppress these morphological changes in HDFs were evaluated, we found that an extract of Lilium 'Casa Blanca' (LCB) suppressed UVA-induced alterations in the shape of HDFs, which are typically followed by inhibition of collagen reduction. An analysis of the active compounds in LCB extract led to the identification of regaloside I, which had a structure of phenylpropanoid glycerol glucoside, as the active compound inhibiting the upregulation of CAPZA1. Therefore, inhibition of UVA-induced morphological changes in HDFs is considered to be promising way for the suppression of collagen reduction in photoaging. PMID:27539902

  16. Ultrastructural morphologic changes in mycobacterial biofilm in different extreme condition.

    PubMed

    Kumar, Virendra; Sachan, Tarun Kumar; Sharma, Pragya; Rawat, Krishna Dutta

    2015-02-01

    The aim of this study was to investigate the morphologic and ultrastructural features of biofilms of slow and fast-growing mycobacteria in different stress conditions, presence and absence of oleic acid albumin dextrose catalase (OADC) enrichment and at different temperatures: 30, 37 and 42 °C. Four hundred mycobacterial isolates were taken. The biomass of each biofilm was quantified using a modified microtiter plate assay method. Isolates were divided into those that formed fully established biofilms, moderately attached biofilms and weakly adherent biofilms by comparison with a known biofilm-forming strain. The large quantity of biofilm was produced by Mycobacterium smegmatis at temperature 37 and 42 °C as compared to 30 °C. Mycobacterium fortuitum and M. avium developed large amount of biofilm at 30 °C as compared to 37 and 42 °C. Mycobacterium tuberculosis developed strong biofilm at 37 °C and no biofilm at 30 and 42 °C in Sauton's media. The selected non-tuberculous mycobacteria and H37Rv developed strong biofilm in the presence of OADC enrichment in Sauton's medium. Microscopic examination of biofilms by scanning electron microscopy revealed that poorly adherent biofilm formers failed to colonize the entire surface of the microtiter well. While moderately adherent biofilm formers grew in uniform monolayers but failed to develop a mature three-dimensional structure. SEM analysis of an isolate representative of the group formed fully established biofilms with a textured, multi-layered, three-dimensional structure. PMID:25192360

  17. Mitigating the effects of surface morphology changes during ultrasonic wall thickness monitoring

    NASA Astrophysics Data System (ADS)

    Cegla, Frederic; Gajdacsi, Attila

    2016-02-01

    Ultrasonic wall thickness monitoring using permanently installed sensors has become a tool to monitor pipe wall thicknesses online and during plant operation. The repeatability of measurements with permanently installed transducers is excellent and can be in the nanometer range. It has, however, also been shown that the measured wall thickness is dependent on surface morphology and that when there are changes in surface morphology the monitored thickness trends can be affected. With an adaptive cross correlation approach, this effect can be successfully muted. However, under some surface morphology change conditions, this can also lead to inaccuracies. Here, an approach to detect when surface morphology changes can influence trend accuracies is presented. This method requires the combination of measurements from several sensors that independently sample an area where the same wall loss mechanism is assumed to occur. Simulation results for the effectiveness of the technique are presented.

  18. Neuronal and brain morphological changes in animal models of schizophrenia.

    PubMed

    Flores, Gonzalo; Morales-Medina, Julio César; Diaz, Alfonso

    2016-03-15

    Schizophrenia, a severe and debilitating disorder with a high social burden, affects 1% of the adult world population. Available therapies are unable to treat all the symptoms, and result in strong side effects. For this reason, numerous animal models have been generated to elucidate the pathophysiology of this disorder. All these models present neuronal remodeling and abnormalities in spine stability. It is well known that the complexity in dendritic arborization determines the number of receptive synaptic contacts. Also the loss of dendritic spines and arbor stability are strongly associated with schizophrenia. This review evaluates changes in spine density and dendritic arborization in animal models of schizophrenia. By understanding these changes, pharmacological treatments can be designed to target specific neural systems to attenuate neuronal remodeling and associated behavioral deficits. PMID:26738967

  19. Morphological change in cranial shape following the transition to agriculture across western Eurasia.

    PubMed

    Cheronet, Olivia; Finarelli, John A; Pinhasi, Ron

    2016-01-01

    The Neolithic transition brought about fundamental social, dietary and behavioural changes in human populations, which, in turn, impacted skeletal morphology. Crania are shaped through diverse genetic, ontogenetic and environmental factors, reflecting various elements of an individual's life. To determine the transition's effect on cranial morphology, we investigated its potential impact on the face and vault, two elements potentially responding to different influences. Three datasets from geographically distant regions (Ukraine, Iberia, and the Levant plus Anatolia) were analysed. Craniometric measurements were used to compare the morphology of pre-transition populations with that of agricultural populations. The Neolithic transition corresponds to a statistically significant increase only in cranial breadth of the Ukrainian vaults, while facial morphology shows no consistent transformations, despite expected changes related to the modification of masticatory behaviour. The broadening of Ukrainian vaults may be attributable to dietary and/or social changes. However, the lack of change observed in the other geographical regions and the lack of consistent change in facial morphology are surprising. Although the transition from foraging to farming is a process that took place repeatedly across the globe, different characteristics of transitions seem responsible for idiosyncratic responses in cranial morphology. PMID:27622425

  20. Changes in caecal microbiota and mucosal morphology of weaned pigs.

    PubMed

    Castillo, Marisol; Martín-Orúe, Susana M; Nofrarías, Miquel; Manzanilla, Edgar G; Gasa, Josep

    2007-10-01

    An experiment was designed to monitor the changes in caecal microbiota associated with early weaning. Twelve piglets (20+/-2 days) from six different litters were selected from a commercial source. For the two experimental groups, one animal from each litter was weaned onto a post-weaning diet (W) and the other remained with the sow (S). After 1 week, animals were sacrificed and caecal samples taken. Microbial counts for total bacteria, enterobacteria and lactobacilli populations were determined by quantitative PCR using SYBR Green dye. Microbial profiles were assessed by terminal restriction fragment length polymorphism (t-RFLP). Weaning promoted an increase in the enterobacteria:lactobacilli ratio (0.27 versus 1.67 log/log 16S rRNA gene copy number, P=0.05). Total bacteria and richness of the caecal microbial ecosystem (number of peaks) were similar in both experimental groups (49.3 for S and 53.4 for W, respectively, P=0.22), although the band patterns were clearly grouped in two different clusters by dendogram analysis. Weaning was also associated with a decrease in crypt density, an increase in mytotic index and a decrease in the number of goblet cells. A reduced immunological response was also observed and was manifested by an increase in intraepithelial lymphocytes and lymphocyte density in the lamina propria. Weaning appears to be critical in the establishment of the caecal microbiota in pigs with important changes, particularly in microbial groups and in caecal mucosal architecture. PMID:17532151

  1. Transcriptomics of morphological color change in polychromatic Midas cichlids

    PubMed Central

    2013-01-01

    Background Animal pigmentation has received much attention in evolutionary biology research due to its strong implications for adaptation and speciation. However, apart from a few cases the genetic changes associated with these evolutionary processes remain largely unknown. The Midas cichlid fish from Central America are an ideal model system for investigating pigmentation traits that may also play a role in speciation. Most Midas cichlids maintain their melanophores and exhibit a grayish (normal) color pattern throughout their lives. A minority of individuals, however, undergo color change and exhibit a distinctive gold or even white coloration in adulthood. The ontogenetic color change in the Midas cichlids may also shed light on the molecular mechanisms underlying pigmentation disorders in humans. Results Here we use next-generation sequencing (Illumina) RNAseq analyses to compare skin transcriptome-wide expression levels in three distinct stages of color transformation in Midas cichlids. cDNA libraries of scale tissue, for six biological replicates of each group, were generated and sequenced using Illumina technology. Using a combination of three differential expression (DE) analyses we identified 46 candidate genes that showed DE between the color morphs. We find evidence for two key DE patterns: a) genes involved in melanosomal pathways are up-regulated in normally pigmented fish; and b) immediate early and inflammatory response genes were up-regulated in transitional fish, a response that parallels some human skin disorders such as melanoma formation and psoriasis. One of the DE genes segregates with the gold phenotype in a genetic cross and might be associated with incipient speciation in this highly “species-rich” lineage of cichlids. Conclusions Using transcriptomic analyses we successfully identified key expression differences between different color morphs of Midas cichlid fish. These differentially expressed genes have important implications for

  2. Dynamics of β-adrenergic/cAMP signaling and morphological changes in cultured astrocytes.

    PubMed

    Vardjan, Nina; Kreft, Marko; Zorec, Robert

    2014-04-01

    The morphology of astrocytes, likely regulated by cAMP, determines the structural association between astrocytes and the synapse, consequently modulating synaptic function. β-Adrenergic receptors (β-AR), which increase cytosolic cAMP concentration ([cAMP]i ), may affect cell morphology. However, the real-time dynamics of β-AR-mediated cAMP signaling in single live astrocytes and its effect on cell morphology have not been studied. We used the fluorescence resonance energy transfer (FRET)-based cAMP biosensor Epac1-camps to study time-dependent changes in [cAMP]i ; morphological changes in primary rat astrocytes were monitored by real-time confocal microscopy. Stimulation of β-AR by adrenaline, noradrenaline, and isoprenaline, a specific agonist of β-AR, rapidly increased [cAMP]i (∼15 s). The FRET signal response, mediated via β-AR, was faster than in the presence of forskolin (twofold) and dibutyryl-cAMP (>35-fold), which directly activate adenylyl cyclase and Epac1-camps, respectively, likely due to slow entry of these agents into the cytosol. Oscillations in [cAMP]i have not been recorded, indicating that cAMP-dependent processes operate in a slow time domain. Most Epac1-camps expressing astrocytes revealed a morphological change upon β-AR activation and attained a stellate morphology within 1 h. The morphological changes exhibited a bell-shaped dependency on [cAMP]i . The 5-10% decrease in cell cross-sectional area and the 30-50% increase in cell perimeter are likely due to withdrawal of the cytoplasm to the perinuclear region and the appearance of protrusions on the surface of astrocytes. Because astrocyte processes ensheath neurons, β-AR/cAMP-mediated morphological changes can modify the geometry of the extracellular space, affecting synaptic, neuronal, and astrocyte functions in health and disease. PMID:24464905

  3. Changes in particle morphology during illitization: an experimental study

    USGS Publications Warehouse

    Whitney, G.; Velde, B.

    1993-01-01

    Smectite was reacted at several temperatures between 200??C and 500??C to produce interstratified illite/smectite (I/S) with different proportions of expandable layers. Dispersed and sedimented products were examined using a transmission electron microscope. Particle size and aspect ratio showed no systematic change as a function of reaction extent during RO illitization. However, particles exhibited rounded edges during the early stages of the reaction, suggesting some dissolution of primary smectite. The thickening of particles is thought to be produced by the nucleation and precipitation of secondary illite layers on primary smectite layers. In the most extensively reacted I/S, particles have become aggregated into clumps or quasicrystals by lateral growth of illite layers. In highly illitic I/S, these aggregates took on an overall euhedral form and became crystallographically contiguous, producing single crystal electron diffraction patterns. -from Authors

  4. River restoration: morphological, hydrological, biogeochemical and ecological changes and challenges

    NASA Astrophysics Data System (ADS)

    Schirmer, M.; Luster, J.; Linde, N.; Perona, P.; Mitchell, E. A. D.; Barry, D. A.; Cirpka, O. A.; Schneider, P.; Vogt, T.; Durisch-Kaiser, E.

    2013-08-01

    River restoration is essential as a means to enhance river dynamics, environmental heterogeneity and biodiversity. The underlying processes governing the dynamic changes need to be understood thoroughly to ensure that restoration projects meet their goals. In particular, we need to understand quantitatively how hydromorphological variability relates to ecosystem functioning and services, biodiversity and (ground)water quality in restored river corridors. Here, we provide a short overview on the literature and present a study of a restored river corridor in Switzerland combining physical, chemical, and biological observations with modeling. The results show complex spatial patterns of bank infiltration, habitat-type, biotic communities and biogeochemical processes. In particular, we found an increase in taxonomic and functional diversity for earthworms, testate amoebae and bacteria in the restored part of the river. This complexity is driven by river hydrology and morphodynamics, which are in turn actively coupled to riparian vegetation processes. Given this complexity and the multiple constraints on the uses and management of floodplains, a multi-disciplinary approach is needed to monitor the success of restoration measures and to make recommendations for future restoration projects.

  5. Dramatic niche shifts and morphological change in two insular bird species

    PubMed Central

    Alström, Per; Jønsson, Knud A.; Fjeldså, Jon; Ödeen, Anders; Ericson, Per G. P.; Irestedt, Martin

    2015-01-01

    Colonizations of islands are often associated with rapid morphological divergence. We present two previously unrecognized cases of dramatic morphological change and niche shifts in connection with colonization of tropical forest-covered islands. These evolutionary changes have concealed the fact that the passerine birds madanga, Madanga ruficollis, from Buru, Indonesia, and São Tomé shorttail, Amaurocichla bocagii, from São Tomé, Gulf of Guinea, are forest-adapted members of the family Motacillidae (pipits and wagtails). We show that Madanga has diverged mainly in plumage, which may be the result of selection for improved camouflage in its new arboreal niche, while selection pressures for other morphological changes have probably been weak owing to preadaptations for the novel niche. By contrast, we suggest that Amaurocichla's niche change has led to divergence in both structure and plumage. PMID:26064613

  6. Morphological variation in salamanders and their potential response to climate change

    PubMed Central

    Ficetola, Gentile Francesco; Colleoni, Emiliano; Renaud, Julien; Scali, Stefano; Padoa-Schioppa, Emilio; Thuiller, Wilfried

    2016-01-01

    Despite the recognition that some species might quickly adapt to new conditions under climate change, demonstrating and predicting such a fundamental response is challenging. Morphological variations in response to climate may be caused by evolutionary changes or phenotypic plasticity, or both, but teasing apart these processes is difficult. Here we built on the number of thoracic vertebrae (NTV) in ectothermic vertebrates, a known genetically-based feature, to establish a link with body size and evaluate how climate change might affect the future morphological response of this group of species. First we show that in old-world salamanders, NTV variation is strongly related to changes in body size. Secondly, using 22 salamander species as a case study, we found support for relationships between the spatial variation in selected bioclimatic variables and NTV for most of species. For 44% of species, precipitation and aridity were the predominant drivers of geographical variation of the NTV. Temperature features were dominant for 31% of species, while for 19% temperature and precipitation played a comparable role. This two-step analysis demonstrates that ectothermic vertebrates may evolve in response to climate change by modifying the number of thoracic vertebrae. These findings allow to develop scenarios for potential morphological evolution under future climate change, and to identify areas and species in which the most marked evolutionary responses are expected. Resistance to climate change estimated from species distribution models was positively related to present-day species morphological response, suggesting that the ability of morphological evolution may play a role for species’ persistence under climate change. The possibility that present-day capacity for local adaptation might help the resistance response to climate change can be integrated into analyses of the impact of global changes, and should also be considered when planning management actions

  7. Morphological variation in salamanders and their potential response to climate change.

    PubMed

    Ficetola, Gentile Francesco; Colleoni, Emiliano; Renaud, Julien; Scali, Stefano; Padoa-Schioppa, Emilio; Thuiller, Wilfried

    2016-06-01

    Despite the recognition that some species might quickly adapt to new conditions under climate change, demonstrating and predicting such a fundamental response is challenging. Morphological variations in response to climate may be caused by evolutionary changes or phenotypic plasticity, or both, but teasing apart these processes is difficult. Here, we built on the number of thoracic vertebrae (NTV) in ectothermic vertebrates, a known genetically based feature, to establish a link with body size and evaluate how climate change might affect the future morphological response of this group of species. First, we show that in old-world salamanders, NTV variation is strongly related to changes in body size. Secondly, using 22 salamander species as a case study, we found support for relationships between the spatial variation in selected bioclimatic variables and NTV for most of species. For 44% of species, precipitation and aridity were the predominant drivers of geographical variation of the NTV. Temperature features were dominant for 31% of species, while for 19% temperature and precipitation played a comparable role. This two-step analysis demonstrates that ectothermic vertebrates may evolve in response to climate change by modifying the number of thoracic vertebrae. These findings allow to develop scenarios for potential morphological evolution under future climate change and to identify areas and species in which the most marked evolutionary responses are expected. Resistance to climate change estimated from species distribution models was positively related to present-day species morphological response, suggesting that the ability of morphological evolution may play a role for species' persistence under climate change. The possibility that present-day capacity for local adaptation might help the resistance response to climate change can be integrated into analyses of the impact of global changes and should also be considered when planning management actions favouring

  8. Morphology and polymorphic phase changes of calcium carbonate micro/nanocrystals using fruit extracts.

    PubMed

    Ankamwar, Balaprasad

    2011-05-01

    This study reveals the morphology and polymorphic phase changes of calcium carbonate crystals into a mixture of calcite and aragonite micro/nanocrystals of interesting morphology at room temperature by a simple reaction with fruit extracts of Tamarindus indica and Emblica officinalis respectively by mixing CaCO3 solutions with their corresponding extracts. The control experiments were carried out to establish the plausible role of tartaric acid from Tamarindus indica and ascorbic acid from Emblica officinalis in this regard. The quantitative determination of CaCO3 phases was done based on the use of intensities obtained from corresponding XRD spectrum. The molar % of aragonite was found to be more in case of TA and AA rather than TI and EO respectively, however the calcite was observed to be the predominant phase in all four reactions. Interestingly, the TI changes the rhombohedral morphology of calcite to elongated rods, whereas EO induces a great polymorphic phase change. PMID:21780397

  9. Morphological and Histopathological Changes in Orofacial Structures of Experimentally Developed Acromegaly-Like Rats: An Overview

    PubMed Central

    Iikubo, Masahiro; Kojima, Ikuho; Sakamoto, Maya; Kobayashi, Akane; Ikeda, Hidetoshi; Sasano, Takashi

    2012-01-01

    Tongue enlargement and mandibular prognathism are clinically recognized in almost all patients with acromegaly. An acromegaly-like rat model recently developed by exogenous administration of insulin-like growth factor I (IGF-I) was used to investigate morphological and histopathological changes in orofacial structures and to clarify whether these changes were reversible. Exogenous administration of IGF-I evoked specific enlargement of the tongue with identifiable histopathological changes (increased muscle bundle width, increased space between muscle bundles, and increased epithelial thickness), elongation of the mandibular alveolar bone and ascending ramus, and lateral expansion of the mandibular dental arch. Regarding histopathological changes in the mandibular condyle, the cartilaginous layer width, bone matrix ratio, and number of osteoblasts were all significantly greater in this rat model. After normalization of the circulating IGF-I level, tongue enlargement and histopathological changes in the tongue and mandibular condyle were reversible, whereas morphological skeletal changes in the mandible remained. PMID:22518118

  10. Adsorbate-driven morphological changes on Cu(111) nano-pits

    DOE PAGESBeta

    Mudiyanselage, K.; Xu, F.; Hoffmann, F. M.; Hrbek, J.; Waluyo, I.; Boscoboinik, J. A.; Stacchiola, D. J.

    2014-12-09

    Adsorbate-driven morphological changes of pitted-Cu(111) surfaces have been investigated following the adsorption and desorption of CO and H. The morphology of the pitted-Cu(111) surfaces, prepared by Ar+ sputtering, exposed a few atomic layers deep nested hexagonal pits of diameters from 8 to 38 nm with steep step bundles. The roughness of pitted-Cu(111) surfaces can be healed by heating to 450-500 K in vacuum. Adsorption of CO on the pitted-Cu(111) surface leads to two infrared peaks at 2089-2090 and 2101-2105 cm-1 for CO adsorbed on under-coordinated sites in addition to the peak at 2071 cm-1 for CO adsorbed on atop sitesmore » of the close-packed Cu(111) surface. CO adsorbed on under-coordinated sites is thermally more stable than that of atop Cu(111) sites. Annealing of the CO-covered surface from 100 to 300 K leads to minor changes of the surface morphology. In contrast, annealing of a H covered surface to 300 K creates a smooth Cu(111) surface as deduced from infrared data of adsorbed CO and scanning tunnelling microscopy (STM) imaging. The observation of significant adsorbate-driven morphological changes with H is attributed to its stronger modification of the Cu(111) surface by the formation of a sub-surface hydride with a hexagonal structure, which relaxes into the healed Cu(111) surface upon hydrogen desorption. These morphological changes occur ~150 K below the temperature required for healing of the pitted-Cu(111) surface by annealing in vacuum. In contrast, the adsorption of CO, which only interacts with the top-most Cu layer and desorbs by 160 K, does not significantly change the morphology of the pitted-Cu(111) surface.« less

  11. Adsorbate-driven morphological changes on Cu(111) nano-pits

    SciTech Connect

    Mudiyanselage, K.; Xu, F.; Hoffmann, F. M.; Hrbek, J.; Waluyo, I.; Boscoboinik, J. A.; Stacchiola, D. J.

    2014-12-09

    Adsorbate-driven morphological changes of pitted-Cu(111) surfaces have been investigated following the adsorption and desorption of CO and H. The morphology of the pitted-Cu(111) surfaces, prepared by Ar+ sputtering, exposed a few atomic layers deep nested hexagonal pits of diameters from 8 to 38 nm with steep step bundles. The roughness of pitted-Cu(111) surfaces can be healed by heating to 450-500 K in vacuum. Adsorption of CO on the pitted-Cu(111) surface leads to two infrared peaks at 2089-2090 and 2101-2105 cm-1 for CO adsorbed on under-coordinated sites in addition to the peak at 2071 cm-1 for CO adsorbed on atop sites of the close-packed Cu(111) surface. CO adsorbed on under-coordinated sites is thermally more stable than that of atop Cu(111) sites. Annealing of the CO-covered surface from 100 to 300 K leads to minor changes of the surface morphology. In contrast, annealing of a H covered surface to 300 K creates a smooth Cu(111) surface as deduced from infrared data of adsorbed CO and scanning tunnelling microscopy (STM) imaging. The observation of significant adsorbate-driven morphological changes with H is attributed to its stronger modification of the Cu(111) surface by the formation of a sub-surface hydride with a hexagonal structure, which relaxes into the healed Cu(111) surface upon hydrogen desorption. These morphological changes occur ~150 K below the temperature required for healing of the pitted-Cu(111) surface by annealing in vacuum. In contrast, the adsorption of CO, which only interacts with the top-most Cu layer and desorbs by 160 K, does not significantly change the morphology of the pitted-Cu(111) surface.

  12. Dynamic changes in brewing yeast cells in culture revealed by statistical analyses of yeast morphological data.

    PubMed

    Ohnuki, Shinsuke; Enomoto, Kenichi; Yoshimoto, Hiroyuki; Ohya, Yoshikazu

    2014-03-01

    The vitality of brewing yeasts has been used to monitor their physiological state during fermentation. To investigate the fermentation process, we used the image processing software, CalMorph, which generates morphological data on yeast mother cells and bud shape, nuclear shape and location, and actin distribution. We found that 248 parameters changed significantly during fermentation. Successive use of principal component analysis (PCA) revealed several important features of yeast, providing insight into the dynamic changes in the yeast population. First, PCA indicated that much of the observed variability in the experiment was summarized in just two components: a change with a peak and a change over time. Second, PCA indicated the independent and important morphological features responsible for dynamic changes: budding ratio, nucleus position, neck position, and actin organization. Thus, the large amount of data provided by imaging analysis can be used to monitor the fermentation processes involved in beer and bioethanol production. PMID:24012106

  13. Molecular and morphological changes in zebrafish following transient ethanol exposure during defined developmental stages.

    PubMed

    Zhang, Chengjin; Frazier, Jared M; Chen, Hao; Liu, Yao; Lee, Ju-Ahng; Cole, Gregory J

    2014-01-01

    Alcohol is a teratogen that has diverse effects on brain and craniofacial development, leading to a constellation of developmental disorders referred to as fetal alcohol spectrum disorder (FASD). The molecular basis of ethanol insult remains poorly understood, as does the relationship between molecular and behavioral changes as a consequence of prenatal ethanol exposure. Zebrafish embryos were exposed to a range of ethanol concentrations (0.5-5.0%) during defined developmental stages, and examined for morphological phenotypes characteristic of FASD. Embryos were also analyzed by in situ hybridization for changes in expression of defined cell markers for neural cell types that are sonic hedgehog-dependent. We show that transient binge-like ethanol exposures during defined developmental stages, such as early gastrulation and early neurulation, result in a range of phenotypes and changes in expression of Shh-dependent genes. The severity of fetal alcohol syndrome (FAS) morphological phenotypes, such as microphthalmia, depends on the embryonic stage and concentration of alcohol exposure, as does diminution of retinal Pax6a or forebrain and hindbrain GAD1 gene expression. We also show that changes in eye and brain morphology correlate with changes in Pax6a and GAD1 gene expression. Our results therefore show that transient binge-like ethanol exposures in zebrafish embryos produce the stereotypical morphological phenotypes of FAS, with the severity of phenotypes depending on the developmental stage and alcohol concentration of exposure. PMID:24929233

  14. The morphological changes in transplanted tumors in rats at plasmonic photothermal therapy

    NASA Astrophysics Data System (ADS)

    Bucharskaya, Alla B.; Maslyakova, Galina N.; Navolokin, Nikita A.; Dikht, Nataliya I.; Terentyuk, Georgy S.; Bashkatov, Alexey N.; Genina, Elina A.; Khlebtsov, Boris N.; Khlebtsov, Nikolai G.; Tuchin, Valery V.

    2016-04-01

    The aim of work was to study the morphological changes in transplanted liver tumors of rats after plasmonic photothermal therapy (PPTT). The gold nanorods functionalized with thiolated polyethylene glycol were injected intravenously to rats with transplanted liver cancer PC-1. A day after injection the tumors were irradiated by the infrared 808-nm diode laser. The withdrawal of the animals from the experiment and sampling of tumor tissue for morphological study were performed 24 hours after the laser exposure. The standard histological and immunohistochemical staining with antibodies to proliferation marker Ki-67 and apoptosis marker BAX were used for morphological study of transplanted tumors. The plasmonic photothermal therapy had pronounced damaging effect in rats with transplanted liver tumors expressed in degenerative and necrotic changes in the tumor cells. The decrease of proliferation marker Ki-67 and increase of expression of apoptosis marker BAX were observed in tumor cells after PPTT.

  15. Size, crystal structure and morphology changes of IATO nanoparticles effect on its optical property

    NASA Astrophysics Data System (ADS)

    Hu, Te; Su, Yu-Chang; Liu, Si-Dong; Tang, Hong-Bo; Mu, Shi-Jia; Hu, Ze-Xing

    2014-09-01

    Controlling and changing size, crystal structure and morphology of antimony and tin-doped indium oxide (IATO) nanoparticles can effectively influence their specific optical properties. Nanocube-like, nanorod-like and nanosphere-like IATO nanoparticles have been fabricated from 20 to 200 nm in diameter by sintering as-prepared precursors with distinct crystallographic structures and morphologies. These nano-sized precursors are either cubic In(OH)3 or orthorhombic InOOH with different crystallographic sizes and shapes due to the use of different solvents (deionized water, absolute ethyl alcohol and ethylene glycol) in hydrothermal synthesis process. Characterization and comparison of experimental samples have detailedly demonstrated that desired optical properties of IATO nanoparticles should be attained by appropriate change of size, crystal structure and morphology of IATO nanoparticles.

  16. SIMULATING SUB-DECADAL CHANNEL MORPHOLOGIC CHANGE IN EPHEMERAL STREAM NETWORKS

    EPA Science Inventory

    A distributed watershed model was modified to simulate cumulative channel morphologic
    change from multiple runoff events in ephemeral stream networks. The model incorporates the general design of the event-based Kinematic Runoff and" Erosion Model (KINEROS), which describes t...

  17. Silymarin Inhibits Morphological Changes in LPS-Stimulated Macrophages by Blocking NF-κB Pathway

    PubMed Central

    Kim, Eun Jeong; Lee, Min Young

    2015-01-01

    The present study showed that silymarin, a polyphenolic flavonoid isolated from milk thistle (Silybum marianum), inhibited lipopolysaccharide (LPS)-induced morphological changes in the mouse RAW264.7 macrophage cell line. We also showed that silymarin inhibited the nuclear translocation and transactivation activities of nuclear factor-kappa B (NF-κB), which is important for macrophage activation-associated changes in cell morphology and gene expression of inflammatory cytokines. BAY-11-7085, an NF-κB inhibitor, abrogated LPS-induced morphological changes and NO production, similar to silymarin. Treatment of RAW264.7 cells with silymarin also inhibited LPS-stimulated activation of mitogen-activated protein kinases (MAPKs). Collectively, these experiments demonstrated that silymarin inhibited LPS-induced morphological changes in the RAW264.7 mouse macrophage cell line. Our findings indicated that the most likely mechanism underlying this biological effect involved inhibition of the MAPK pathway and NF-κB activity. Inhibition of these activities by silymarin is a potentially useful strategy for the treatment of inflammation because of the critical roles played by MAPK and NF-κB in mediating inflammatory responses in macrophages. PMID:25954125

  18. Hexamethylene bisacetamide induces morphologic changes and increased synthesis of procollagen in cell line from glioblastoma multiforme.

    PubMed Central

    Rabson, A S; Stern, R; Tralka, T S; Costa, J; Wilczek, J

    1977-01-01

    Addition to hexamethylene bisacetamide (diacetyldiaminohexane) to cultures of a malignant mesenchymal cell line derived from a human glioblastoma multiforme induces morphological changes and stimulates the synthesis of procollagen. The morphological changes include cell elongation, an increase of extracellular material with staining properties of collagen by light microscopy, and an increase in extracellular 220-A fibrils by electron microscopy. The rate of procollagen synthesis increased as much as 20-fold, and the ratio of type I:type III procollagen changed, with type I becoming the predominant form. The change in type I:type III ratio is similar to that seen in the maturation of normal fetal to adult connective tissue. Images PMID:200944

  19. [The significance of morphologic changes in acute occlusive cholecystitis for determining the surgical approach].

    PubMed

    Iukhtin, V I; Khripun, A I; Raksha, A P; Zhukotskiĭ, A V; Sergeeva, N A; Dorofeeva, I M; Belous, G G

    1996-01-01

    Specific morphological and functional changes in the liver in acute obturative cholecystitis have been experimentally studied in 30 dogs and clinically examined in 21 patients. No morphological substrate of liver insufficiency were found in early period of acute obturative cholecystitis. Early changes in the liver are of reactive nature and have the features of active nonspecific hepatitis. The reactions of compensation and decompensation are changing each other periodically. The intensive reactions of compensation take place in the first 2 or 3 days of disease. The reactions of compensation weaken gradually. There is no correlation between changes in the liver and in blood serum. The early surgery and laparoscopic procedures in acute obturative cholecystitis are advocated. PMID:8965448

  20. Changes, and the Relevance Thereof, in Mitochondrial Morphology during Differentiation into Endothelial Cells

    PubMed Central

    Shin, Ji Won; Park, So Hee; Kang, Yun Gyeong; Wu, Yanru; Choi, Hyun Ju

    2016-01-01

    The roles of mitochondria in various physiological functions of vascular endothelial cells have been investigated extensively. Morphological studies in relation to physiological functions have been performed. However, there have been few reports of morphological investigations related to stem cell differentiation. This was the first morphological study of mitochondria in relation to endothelial differentiation and focused on quantitative analysis of changes in mitochondrial morphology, number, area, and length during differentiation of human mesenchymal stem cells (hMSCs) into endothelial-like cells. To induce differentiation, we engaged vascular endothelial growth factors and flow-induced shear stress. Cells were classified according to the expression of von Willebrand factor as hMSCs, differentiating cells, and almost fully differentiated cells. Based on imaging analysis, we investigated changes in mitochondrial number, area, and length. In addition, mitochondrial networks were quantified on a single-mitochondrion basis by introducing a branch form factor. The data indicated that the mitochondrial number, area per cell, and length were decreased with differentiation. The mitochondrial morphology became simpler with progression of differentiation. These findings could be explained in view of energy level during differentiation; a higher level of energy is needed during differentiation, with larger numbers of mitochondria with branches. Application of this method to differentiation into other lineages will explain the energy levels required to control stem cell differentiation. PMID:27517609

  1. Changes, and the Relevance Thereof, in Mitochondrial Morphology during Differentiation into Endothelial Cells.

    PubMed

    Shin, Ji Won; Park, So Hee; Kang, Yun Gyeong; Wu, Yanru; Choi, Hyun Ju; Shin, Jung-Woog

    2016-01-01

    The roles of mitochondria in various physiological functions of vascular endothelial cells have been investigated extensively. Morphological studies in relation to physiological functions have been performed. However, there have been few reports of morphological investigations related to stem cell differentiation. This was the first morphological study of mitochondria in relation to endothelial differentiation and focused on quantitative analysis of changes in mitochondrial morphology, number, area, and length during differentiation of human mesenchymal stem cells (hMSCs) into endothelial-like cells. To induce differentiation, we engaged vascular endothelial growth factors and flow-induced shear stress. Cells were classified according to the expression of von Willebrand factor as hMSCs, differentiating cells, and almost fully differentiated cells. Based on imaging analysis, we investigated changes in mitochondrial number, area, and length. In addition, mitochondrial networks were quantified on a single-mitochondrion basis by introducing a branch form factor. The data indicated that the mitochondrial number, area per cell, and length were decreased with differentiation. The mitochondrial morphology became simpler with progression of differentiation. These findings could be explained in view of energy level during differentiation; a higher level of energy is needed during differentiation, with larger numbers of mitochondria with branches. Application of this method to differentiation into other lineages will explain the energy levels required to control stem cell differentiation. PMID:27517609

  2. Morphological changes in pedal phalanges through ornithopod dinosaur evolution: a biomechanical approach.

    PubMed

    Moreno, Karen; Carrano, Matthew T; Snyder, Rebecca

    2007-01-01

    The evolution of ornithopod dinosaurs provides a well-documented example of the transition from digitigrady to subunguligrady. During this transition, the ornithopod pes was drastically altered from the plesiomorphic dinosaurian morphology (four digits, claw-shaped unguals, strongly concavo-convex joints, phalanges longer than wide, excavated collateral ligament fossae, presence of sagittal ridge, and prominent processes for the attachment of tendons) to a more derived condition (tridactyly, modification of the unguals into hooves, phalanges wider and thinner than long, lack of collateral ligament fossae, loss of sagittal ridge and tendon attachment processes, relatively flattened articular surfaces). These changes are particularly noteworthy given the overall conservatism in pedal morphology seen across Dinosauria. But what are the functional consequences of these specific morphological transitions? To study them, we examine a wide range of pedal morphologies in four non-avian dinosaurs and two birds. Our analyses of the external morphology, two-dimensional models (using Finite Element Analysis), and internal bone structure demonstrate that this evolutionary shift was accompanied by a loss of digit mobility and flexibility. In addition, pedal posture was modified to better align the pes with the main direction of the ground reaction force, thus becoming well suited to support high loads. These conclusions can be applied to other, parallel evolutionary changes (in both dinosaurs and mammals) that involved similar transitions to a subunguligrade posture. PMID:17146773

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

    SciTech Connect

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

    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, 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

  4. In situ 24 kHz coherent imaging of morphology change in laser percussion drilling.

    PubMed

    Webster, Paul J L; Yu, Joe X Z; Leung, Ben Y C; Anderson, Mitchell D; Yang, Victor X D; Fraser, James M

    2010-03-01

    We observe sample morphology changes in real time (24 kHz) during and between percussion drilling pulses by integrating a low-coherence microscope into a laser micromachining platform. Nonuniform cut speed and sidewall evolution in stainless steel are observed to strongly depend on assist gas. Interpulse morphology relaxation such as hole refill is directly imaged, showing dramatic differences in the material removal process dependent on pulse duration/peak power (micros/0.1 kW, ps/20 MW) and material (steel, lead zirconate titanate PZT). Blind hole depth precision is improved by over 1 order of magnitude using in situ feedback from the imaging system. PMID:20195306

  5. Time Dependent Assessment of Morphological Changes: Leukodepleted Packed Red Blood Cells Stored in SAGM

    PubMed Central

    2016-01-01

    Usually packed red blood cells (pRBCs) require specific conditions in storage procedures to ensure the maximum shelf life of up to 42 days in 2–6°C. However, molecular and biochemical consequences can affect the stored blood cells; these changes are collectively labeled as storage lesions. In this study, the effect of prolonged storage was assessed through investigating morphological changes and evaluating oxidative stress. Samples from leukodepleted pRBC in SAGM stored at 4°C for 42 days were withdrawn aseptically on day 0, day 14, day 28, and day 42. Morphological changes were observed using scanning electron microscopy and correlated with osmotic fragility and hematocrit. Oxidative injury was studied through assessing MDA level as a marker for lipid peroxidation. Osmotic fragility test showed that extended storage time caused increase in the osmotic fragility. The hematocrit increased by 6.6% from day 0 to day 42. The last 2 weeks show alteration in the morphology with the appearance of echinocytes and spherocytes. Storage lesions and morphological alterations appeared to affect RBCs during the storage period. Further studies should be performed to develop strategies that will aid in the improvement of stored pRBC quality and efficacy. PMID:26904677

  6. Changes of epidermal cell morphology and keratin expression induced by inhibitors of protein kinase C.

    PubMed

    Hegemann, L; Wevers, A; Bonnekoh, B; Mahrle, G

    1992-03-01

    Several lines of evidence show protein kinase C as being involved in various regulatory processes in keratinocyte biology, e.g. proliferation and differentiation. In the present study, we investigated the effects of three different inhibitors of protein kinase C, staurosporine, CP 46'665-1, and tiflucarbine, on cell morphology and keratin expression in a non-tumorigenic human keratinocyte cell line (HaCaT cells). Staurosporine, being the most potent inhibitor of protein kinase C activity in vitro, and CP 46'665-1 induced morphological transformation to a fibroblast-like cell shape. In contrast, no changes in cell morphology were observed after exposure to tiflucarbine. The investigation of keratin expression in HaCaT cells grown in the presence of the different compounds revealed the following changes: After 72 h of cultivation, keratins 8 and 18 were still expressed in treated cells, whereas expression of keratin 13 was decreased as compared to control cells. Immunoblotting to detect vimentin demonstrated its absence in treated and control cells. Since tiflucarbine is known as a dual protein kinase C/calmodulin inhibitor whereas staurosporine and CP 46'665-1 do not antagonize calmodulin function, it might be possible that not only protein kinase C but also calmodulin is involved in the process leading to the morphological changes. PMID:1376142

  7. Channel degradation and restoration of an Alpine river and related morphological changes

    NASA Astrophysics Data System (ADS)

    Campana, Daniela; Marchese, Enrico; Theule, Joshua I.; Comiti, Francesco

    2014-09-01

    River degradation and thus necessity for restoration are major issues worldwide. However, adequate methodologies to assess morphological variations linked to these actions and the morphological success of restoration interventions are still to be determined. The Ahr River (South Tyrol, Italian Alps) was characterized until the mid-twentieth century by an anabranching and meandering pattern, but starting from the 1960s it underwent intense channel degradation in terms of narrowing, incision, and floodplain disconnection. In the period 2003-2011, several reaches of the Ahr River were restored by widening and raising the channel bed. The planimetric changes that occurred historically in the Ahr River were determined by the interpretation of 10 maps and aerial photos covering the period 1820-2011. The estimation of the incision that occurred during the degradation phase was assessed by the difference in elevation between gravel surfaces, whereas the changes introduced by restoration interventions in two reaches were evaluated through the comparison of topographic cross sections surveyed in year 2000 and a high-resolution bathymetric LiDAR survey flown in late 2012. The MQI (Morphological Quality Index) was applied to different reaches in order to test how assessment methodologies respond to degradation and restoration actions. The combined analysis of planform and vertical changes indicates that gravel mining has been the largest pressure for the river, but a change in sediment/flow regimes probably led to the channel adjustments that occurred during the early twentieth century. The restoration measures have locally increased channel width, elevation, and morphometrical diversity compared to the unrestored reaches, as well as the morphological quality assessed by MQI. However, the extent of the modifications brought about by restoration works differs between the two restored reaches, pointing out the need for a quantitative analysis of the historical evolution of each

  8. Might short term rockglacier surface morphological changes be attributed to permafrost degradation ?

    NASA Astrophysics Data System (ADS)

    Perrier, Romain; Cossart, Etienne; Fort, Monique

    2015-04-01

    In high mountain environments, permafrost is increasingly affected by climate change. Rockglaciers represent the expression of creeping permafrost: they are generally considered as good geo-indicators of cryosphere distribution and evolution. Research dealing with the effect of climate change on rockglacier degradation is mostly based on photogrammetric studies as well as geophysics. Major results on rockglaciers behavior in relation to increasing mean annual air temperature are summarized as follows. Firstly, photogrammetry analysis shows that rockglacier surface velocities are higher when the permafrost temperature and/or water content increase within the rockglacier system; this can sometimes lead to the destabilization/collapse of rockglaciers. Secondly, geophysical studies demonstrate a decrease in resistivities within the rockglacier body in relation to a decrease in ice content hence suggesting a degradation of permafrost. Although these methods are appropriate for studying the effects of climate change on mountain permafrost and rockglacier evolution, their application is fairly costly and time-consuming, and are usually restricted to one or two study cases. Our investigations over a wider area up to regional scale require completing our approach by using surface morphological changes, a method that can identify potential degradation in a warming context. In this context, this work intends to characterize short terms (multi-decades) surface morphological changes at rockglacier scale and to determine if these changes may be attributed to potential permafrost degradation. Our investigations have been carried out in both Clarée and Ubaye valleys, in the French Southern Alps. Here we present our results obtained from the Lac Rouge rockglacier (45°02'49''N, 6°30'16''E; 2600-2825m a.s.l, Clarée valley, French Southern Alps). Analysis of multi-temporal aerial photographs, geomorphological field mapping, electrical resistivity tomographies and surface

  9. Morphological and functional changes in the vertebral column with increasing aquatic adaptation in crocodylomorphs

    PubMed Central

    Molnar, Julia L.; Pierce, Stephanie E.; Bhullar, Bhart-Anjan S.; Turner, Alan H.; Hutchinson, John R.

    2015-01-01

    The lineage leading to modern Crocodylia has undergone dramatic evolutionary changes in morphology, ecology and locomotion over the past 200+ Myr. These functional innovations may be explained in part by morphological changes in the axial skeleton, which is an integral part of the vertebrate locomotor system. Our objective was to estimate changes in osteological range of motion (RoM) and intervertebral joint stiffness of thoracic and lumbar vertebrae with increasing aquatic adaptation in crocodylomorphs. Using three-dimensional virtual models and morphometrics, we compared the modern crocodile Crocodylus to five extinct crocodylomorphs: Terrestrisuchus, Protosuchus, Pelagosaurus, Steneosaurus and Metriorhynchus, which span the spectrum from terrestrial to fully aquatic. In Crocodylus, we also experimentally measured changes in trunk flexibility with sequential removal of osteoderms and soft tissues. Our results for the more aquatic species matched our predictions fairly well, but those for the more terrestrial early crocodylomorphs did not. A likely explanation for this lack of correspondence is the influence of other axial structures, particularly the rigid series of dorsal osteoderms in early crocodylomorphs. The most important structures for determining RoM and stiffness of the trunk in Crocodylus were different in dorsoventral versus mediolateral bending, suggesting that changes in osteoderm and rib morphology over crocodylomorph evolution would have affected movements in some directions more than others. PMID:26716001

  10. Morphological and functional changes in the vertebral column with increasing aquatic adaptation in crocodylomorphs.

    PubMed

    Molnar, Julia L; Pierce, Stephanie E; Bhullar, Bhart-Anjan S; Turner, Alan H; Hutchinson, John R

    2015-11-01

    The lineage leading to modern Crocodylia has undergone dramatic evolutionary changes in morphology, ecology and locomotion over the past 200+ Myr. These functional innovations may be explained in part by morphological changes in the axial skeleton, which is an integral part of the vertebrate locomotor system. Our objective was to estimate changes in osteological range of motion (RoM) and intervertebral joint stiffness of thoracic and lumbar vertebrae with increasing aquatic adaptation in crocodylomorphs. Using three-dimensional virtual models and morphometrics, we compared the modern crocodile Crocodylus to five extinct crocodylomorphs: Terrestrisuchus, Protosuchus, Pelagosaurus, Steneosaurus and Metriorhynchus, which span the spectrum from terrestrial to fully aquatic. In Crocodylus, we also experimentally measured changes in trunk flexibility with sequential removal of osteoderms and soft tissues. Our results for the more aquatic species matched our predictions fairly well, but those for the more terrestrial early crocodylomorphs did not. A likely explanation for this lack of correspondence is the influence of other axial structures, particularly the rigid series of dorsal osteoderms in early crocodylomorphs. The most important structures for determining RoM and stiffness of the trunk in Crocodylus were different in dorsoventral versus mediolateral bending, suggesting that changes in osteoderm and rib morphology over crocodylomorph evolution would have affected movements in some directions more than others. PMID:26716001

  11. Closed-form density-based framework for automatic detection of cellular morphology changes.

    PubMed

    Duong, Tarn; Goud, Bruno; Schauer, Kristine

    2012-05-29

    A primary method for studying cellular function is to examine cell morphology after a given manipulation. Fluorescent markers attached to proteins/intracellular structures of interest in conjunction with 3D fluorescent microscopy are frequently exploited for functional analysis. Despite the central role of morphology comparisons in cell biological approaches, few statistical tools are available that allow biological scientists without a high level of statistical training to quantify the similarity or difference of fluorescent images containing multifactorial information. We transform intracellular structures into kernels and develop a multivariate two-sample test that is nonparametric and asymptotically normal to directly and quantitatively compare cellular morphologies. The asymptotic normality bypasses the computationally intensive calculations used by the usual resampling techniques to compute the P-value. Because all parameters required for the statistical test are estimated directly from the data, it does not require any subjective decisions. Thus, we provide a black-box method for unbiased, automated comparison of cell morphology. We validate the performance of our test statistic for finite synthetic samples and experimental data. Employing our test for the comparison of the morphology of intracellular multivesicular bodies, we detect changes in their distribution after disruption of the cellular microtubule cytoskeleton with high statistical significance in fixed samples and live cell analysis. These results demonstrate that density-based comparison of multivariate image information is a powerful tool for automated detection of cell morphology changes. Moreover, the underlying mathematics of our test statistic is a general technique, which can be applied in situations where two data samples are compared. PMID:22586080

  12. How Will Climate Change Affect Channel Morphology and Salmonid Habitat in Mountain Basins?

    NASA Astrophysics Data System (ADS)

    Buffington, J. M.; Goode, J.

    2010-12-01

    Riverine habitat for salmonids is intimately linked to channel morphology and fluvial processes (channel hydraulics, sediment transport and scour regime) which are, in turn, controlled by watershed hydrology and erosional processes that input sediment to the fluvial system. Climate change has the potential to alter the timing, magnitude, and style of sediment and water inputs to mountain rivers. Channel response to these changes may range from small-scale adjustments of channel characteristics (e.g., width, depth, grain size, scour depth) to larger-scale changes in channel type (e.g., metamorphosis from a pool-riffle channel to a plane-bed morphology). Identifying which parts of the river network will remain relatively stable in response to climate change, and which are likely to cross critical morphologic and scour thresholds is important for predicting effects on salmonid populations. Toward this end, a regime framework is presented for predicting the relative degree of morphologic stability and scour potential in different physiographic settings (different water and sediment regimes). Digital elevation models are used to explore the spatial distribution of these conditions and potential consequences for salmonid habitat across the landscape. Results suggest that the potential for scour and morphologic variability are strongly influenced by hydroclimate; snowmelt channels are relatively stable across floods of different magnitude, while rainfall-dominated channels are more variable and less stable. Transitional changes in hydrologic regime (mixed rain and snow) have the greatest potential for altering geomorphic conditions and salmonid habitat. However, the vulnerability of salmonids to climate-driven changes in scour regime depend on the species and its life history (i.e., depth to which eggs are buried and timing of incubation relative to scouring flows). Overall, the regime approach provides a useful first-order assessment of channel condition and response

  13. Exploring Statistical Characterizations of Morphologic Change and Variability: Fire Island, New York

    NASA Astrophysics Data System (ADS)

    Lentz, E. E.; Hapke, C. J.

    2012-12-01

    A comprehensive understanding of coastal barrier behavior requires high-resolution observations that capture a wide range of morphological changes occurring over a range of spatial and temporal scales. Fire Island National Seashore, located along the coast of Long Island, New York, is a well studied barrier island coast where understanding how morphological changes contribute to barrier island vulnerability have important implications for coastal land management. Previous work has shown that morphologic differences in eastern and western reaches are attributable to the underlying geology and variations sediment transport in the system. In this study, we further explore western and eastern differences and variability with lidar-derived topographic surfaces to provide a unique and comprehensive investigation of dune-beach change at Fire Island, New York. Continuous topographic surfaces generated from 12 lidar surveys collected between 1998 and 2011 are used to examine the three-dimensional variability over a range of time periods over the 50 km long island. Because surveys were collected over a range of seasons and in response to a number of storm events, we explore morphologic configurations reflecting the seasonality, post-storm configuration, and replenishment response to the system through the generation of a representative or average surface. These averaged surfaces provide the context for what would be an expected or typical coastal configuration under certain conditions, and through comparison with an individual event, can be used to derive an event-specific spatial-change signature. To investigate anthropogenic influences, differences in morphology between a survey collected after a substantial beach replenishment project and a typical fair-weather configuration averaged from six surveys are determined. Storm response variations are also explored by assessing differences between Tropical Storm Irene (2011), Nor'Ida (2009), and a typical post

  14. Morphological changes in the kidney, liver and spleen during prolonged administration of iron nanoparticles

    NASA Astrophysics Data System (ADS)

    Navolokin, N. A.; Maslyakova, G. N.; Bucharskya, A. B.; Kong, X. M.; Zuev, V. V.; Medvedev, B. A.; Ignatiev, A. A.; Bochkaryeva, T. V.

    2012-02-01

    We determined the cytotoxic effect of iron nanoparticles of 70 nm, with a single per oral administration in an experiment on white outbred mice. Morphological changes were evaluated in the internal organs. Thus, changes depend on the concentration of nanoparticles at long-term per oral exposure: identified violations of the structure of the liver, kidneys and spleen as venous plethora and degeneration of cells at 250 and 500 mkg / kg dose of nanoparticles are reversible, changes in the organs were pronounced with a dosage of 1000 mkg / kg.

  15. Stress tolerance and biocontrol performance of the yeast antagonist, Candida diversa, change with morphology transition.

    PubMed

    Li, Guangkun; Chi, Mengshan; Chen, Huizhen; Sui, Yuan; Li, Yan; Liu, Yongsheng; Zhang, Xiaojing; Sun, Zhiqiang; Liu, Guoqing; Wang, Qi; Liu, Jia

    2016-02-01

    As an eco-friendly management method, biological control of postharvest diseases, utilizing antagonistic yeasts, is a research topic receiving considerable attention. Detailed knowledge on the biology of yeast antagonists is crucial when considering their potential application and development as biocontrol products. Changes in the growth form, such as single-cell to pseudohyphae, have been associated with the mode of action in postharvest biocontrol yeasts. In this study, the antagonistic yeast, Candida diversa, reversibly shifted from a single-cell morphology on yeast peptone dextrose (YPD) medium with 2 % agar to a pseudohyphal morphology on YPD with 0.3 % agar. The tolerance of the pseudohyphal form to heat and oxidative stresses, as well as the biocontrol efficacy against Botrytis cinerea on apple and kiwifruit stored at 25 and 4 °C, was significantly higher as compared to the single-cell form. This study provides new information on the ability of C. diversa to change its morphology and the impact of the morphology shift on stress tolerance and biocontrol performance. PMID:26637302

  16. Effect of tungsten crystallographic orientation on He-ion-induced surface morphology changes

    SciTech Connect

    Parish, Chad M; Hijazi, Hussein Dib; Meyer III, Harry M; Meyer, Fred W

    2014-01-01

    In order to study the early stages of nanofuzz growth in fusion-plasma-facing tungsten, mirror-polished high-purity tungsten was exposed to 80 eV helium at 1130 C to a fluence of 4 1024 He/m2. The previously smooth surface shows morphology changes, and grains form one of four qualitatively different morphologies: smooth, wavy, pyramidal, or terraced/wide waves. Combining high-resolution scanning electron microscopy (SEM) observations to determine the morphology of each grain with quantitative measurement of the grain's orientation via electron backscatter diffraction (EBSD) in SEM shows that the normal-direction crystallographic orientation of the underlying grain controls the growth morphology. Specifically, near-<001> || normal direction (ND) grains formed pyramids, near-<114> to <112> || ND grains formed wavy and stepped structures, and near-<103> || ND grains remained smooth. Comparisons to control specimens indicate no changes to underlying bulk crystallographic texture, and the effects are attributed to surface energy anisotropy, although, surprisingly, the expected {101} low-energy planes were not the most stable. Future developments to control tungsten texture via thermomechanical processing, ideally obtaining a sharp near- <103> || ND processing texture, may delay the formation of nanofuzz.

  17. [MORPHOLOGICAL CHANGES OF THE LIVER IN OBTURATION JAUNDICE, CAUSED BY CHOLEDOCHOLITHIASIS, DEPENDING ON ITS DURATION].

    PubMed

    Sipliviy, V A; Yevtushenko, D V; Naumova, O V; Andreyeshchev, S A; Yevtushenko, A V

    2016-02-01

    Abstract The results of surgical treatment of 184 patients for obturation jaundice, caused by choledocholithiasis, were analyzed. Morphological changes of the liver were studied in 20 patients. There were three groups of patients delineated, depending on the obturation jaundice duration: up to 7 days, from 8 to 14 days, more than 15 days, and also a group of patients after the bile outflow restoration. The obturation jaundice occurrence in choledocholithiasis is accompanied by significant morphological changes in the liver, severity of which is enhancing while the obturation jaundice persistence increasing. While persistence of obturation jaundice through 8 days and more the connective tissue volume is enhancing, a relative volume of hepatocytes is reducing and a stromal-parenchymatous index is increasing. The bile outflow restoration secures significant reduction of intensity of alterative and inflammatory changes in hepatic parenchyma, as well as activation of reparative processes in the tissue. In cholangitis, caused by P. aeruginosa and E. coli, according to morphological investigations data, in the liver a diffuse purulent cholangitis on background of chronic changes in accordance to duration of the obturation jaundice persists. PMID:27244912

  18. Glial cell morphological and density changes through the lifespan of rhesus macaques.

    PubMed

    Robillard, Katelyn N; Lee, Kim M; Chiu, Kevin B; MacLean, Andrew G

    2016-07-01

    How aging impacts the central nervous system (CNS) is an area of intense interest. Glial morphology is known to affect neuronal and immune function as well as metabolic and homeostatic balance. Activation of glia, both astrocytes and microglia, occurs at several stages during development and aging. The present study analyzed changes in glial morphology and density through the entire lifespan of rhesus macaques, which are physiologically and anatomically similar to humans. We observed apparent increases in gray matter astrocytic process length and process complexity as rhesus macaques matured from juveniles through adulthood. These changes were not attributed to cell enlargement because they were not accompanied by proportional changes in soma or process volume. There was a decrease in white matter microglial process length as rhesus macaques aged. Aging was shown to have a significant effect on gray matter microglial density, with a significant increase in aged macaques compared with adults. Overall, we observed significant changes in glial morphology as macaques age indicative of astrocytic activation with subsequent increase in microglial density in aged macaques. PMID:26851132

  19. Ultrastructural and morphological changes in Leishmania (Viannia) braziliensis treated with synthetic chalcones.

    PubMed

    de Mello, Tatiane F P; Cardoso, Bruna M; Bitencourt, Heriberto R; Donatti, Lucélia; Aristides, Sandra M A; Lonardoni, Maria V C; Silveira, Thais G V

    2016-01-01

    Cutaneous leishmaniasis has an estimated incidence of 1.5 million new cases per year and the treatment options available are old, expensive, toxic, and difficult to administer. Chalcones have shown good activity against several species of Leishmania. However few studies have discussed the mechanisms of action and drug target of this group of compounds in Leishmania. The synthetic chalcones that were evaluated in the present study were previously shown to exhibit activity against Leishmania (Viannia) braziliensis. The objective of the present study was to identify ultrastructural and morphological changes in L. (V.) braziliensis after treatment with three synthetic chalcones (1-3). Promastigotes were treated with chalcones 1-3 and evaluated by transmission and scanning electron microscopy. Cellular and nuclear morphology of the parasites, changes in membrane permeability, and DNA fragmentation in agarose electrophoresis gel were also investigated after exposure to synthetic chalcones. All three synthetic chalcones (1-3) induced ultrastructural alterations in mitochondria, intense vacuolization, two nuclei with rounding of parasites, and cellular and nuclear shrinkage. Chalcones 1-3 also induced no changes in membrane permeability, and presence of nucleosome-sized DNA fragments. Synthetic chalcones 1-3 induced ultrastructural and morphological changes, suggesting that chalcones 1-3 induce apoptosis-like cell death. Further studies should be conducted to elucidate other aspects of the action of these chalcones against Leishmania spp. and their use for the treatment of cutaneous leishmaniasis. PMID:26632504

  20. Use of an Infrared Thermometer with Laser Targeting in Morphological Scene Change Detection for Fire Detection

    NASA Astrophysics Data System (ADS)

    Tickle, Andrew J.; Singh, Harjap; Grindley, Josef E.

    2013-06-01

    Morphological Scene Change Detection (MSCD) is a process typically tasked at detecting relevant changes in a guarded environment for security applications. This can be implemented on a Field Programmable Gate Array (FPGA) by a combination of binary differences based around exclusive-OR (XOR) gates, mathematical morphology and a crucial threshold setting. This is a robust technique and can be applied many areas from leak detection to movement tracking, and further augmented to perform additional functions such as watermarking and facial detection. Fire is a severe problem, and in areas where traditional fire alarm systems are not installed or feasible, it may not be detected until it is too late. Shown here is a way of adapting the traditional Morphological Scene Change Detector (MSCD) with a temperature sensor so if both the temperature sensor and scene change detector are triggered, there is a high likelihood of fire present. Such a system would allow integration into autonomous mobile robots so that not only security patrols could be undertaken, but also fire detection.

  1. Assessing Morphological Changes due to Hydrometeorologic Influences in Mehendiganj Island, Meghna Estuary, Bangladesh

    NASA Astrophysics Data System (ADS)

    Hossain, A.; Ahmed, K. M.; Overeem, I.; Rogers, K. G.

    2014-12-01

    The Ganges-Brahmaputra-Meghna river system is the largest river system in the world with massive discharge rates and sediment loads (annually over one billion tons). Sediment from these rivers has formed one of the largest and most densely populated deltas in the world. The combined rivers discharge through the Meghna estuary into the Bay of Bengal. The study area, Mehendiganj Island, is located in the morphologically dynamic Meghna estuary region of the delta and is characterized by rapid accretion and erosion. The net effect of erosion-accretion processes between the years 1987-2012 was analyzed using Landsat satellite imagery. Time-lapse series were generated over consecutive monsoon periods to estimate net erosion, and reveal that morphological changes are influenced by hydrological conditions (e.g. areal extent of flooding surface, hydrometeorology) driven by high river and sediment discharge, mainly during the seasonal monsoon (wet) period. The hydrological conditions and, consequently, the morphological changes exhibit a skewed pattern in annual distribution on account of high-energy condition prevailing during the monsoon. Total erosion and accretion within the study area was estimated to be about 5997 hectares and 2922 hectares, respectively. The measured annual erosion rates were as high as 1493 hectares, which were about 15% of the existing land surface within the study area. Discharge rates and sediment loads over the course of the study period were calculated using a numerical model (WBMsed) and was validated by comparisons with field-measured values. Moreover, hydrological parameters were analyzed in the context of statistical hydrology in order to obtain trends and were correlated with annual accretion and erosion rates attained from the satellite image analysis. Anomalies in the patterns of annual accretion and erosion rates were detected during extreme hydrometeorological events such as high floodwater years and cyclones. The morphological changes

  2. Fuzzy scaling analysis of a mouse mutant with brain morphological changes.

    PubMed

    Pham, Tuan D; Müller, Catharina C; Crane, Denis I

    2009-07-01

    Scaling behavior inherently exists in fundamental biological structures, and the measure of such an attribute can only be known at a given scale of observation. Thus, the properties of fractals and power-law scaling have become attractive for research in biology and medicine because of their potential for discovering patterns and characteristics of complex biological morphologies. Despite the successful applications of fractals for the life sciences, the quantitative measure of the scale invariance expressed by fractal dimensions is limited in more complex situations, such as for histopathological analysis of tissue changes in disease. In this paper, we introduce the concept of fuzzy scaling and its analysis of a mouse mutant with postnatal brain morphological changes. PMID:19369166

  3. Morphological changes in the gills of Heteropneustes fossilis (Bloch) exposed to coal mining effluent water.

    PubMed

    Mylliemngap, B K; Ramanujam, S N

    2012-07-01

    Ultrastructural changes in the gills of cat fish Heteropneustes fossilis exposed to coal mining effluent water collected from Rymbai river in Jaintia hills, Meghalaya, India was investigated under scanning electron microscopy (SEM). The pH of effluent water in the river was significantly low (2.5-3.0) due to coal mining activity in the adjacent areas. The dissolved oxygen (DO) was 7.7 mg l(-1) and conductivity 0.93 mS. Morphological changes like dissociation of the epithelium (E) of branchial arches and gill filaments, hypertrophy and disorientation in the array of lamellae were observed in the treated fish, leading to fish death. The primary and secondary gill lamellae (PL and SL) exhibited fusion, distortion and loss of alignment. Some of the gill rackers showed necrosis at certain places. The morphological features of the gills as revealed through SEM were highly deteriorated when compared to control. PMID:23360000

  4. Arsenic- and selenium-induced changes in spectral reflectance and morphology of soybean plants

    USGS Publications Warehouse

    Milton, N.M.; Ager, C.M.; Eiswerth, B.A.; Power, M.S.

    1989-01-01

    Soybean (Glycine max) plants were grown in hydroponic solutions treated with high concentrations of either arsenic or selenium. Spectral reflectance changes in arsenic-dosed plants included a shift to shorter wavelengths in the long-wavelength edge of the chlorophyll absorption band centered at 680 nm (the red edge) and higher reflectance in the 550-650 nm region. These results are consistent with vegetation reflectance anomalies observed in previous greenhouse experiments and in airborne radiometer studies. The selenium-dosed plants contrast, exhibited a shift to longer wavelengths of the red edge and lower reflectance between 550 nm and 650 wh when compared with control plants. Morphological effects of arsenic uptake included lower overall biomass, stunted and discolored roots, and smaller leaves oriented more vertically than leaves of control plants. Selenium-dosed plants also displayed morphological changes, but root and leaf biomass were less affected than were those of arsenic-dosed plants when compared to control plants. ?? 1989.

  5. Morphological changes in cultures of hippocampus following prenatal irradiation in the rat

    SciTech Connect

    Hamdorf, G.; Shahar, A.; Cervos-Navarro, J.; Scheffler, A.; Sparenberg, A.; Skoberla, A. )

    1990-07-01

    The effect of prenatal irradiation was studied in organotypic cultures of hippocampus, prepared from newborn rats that had been exposed to whole-body irradiation of 1 Gy from a {sup 60}Co-source at day 13 of pregnancy. Light and electron microscopic observations showed remarkable damage to neuronal mitochondria accompanied by extensive swelling, vacuolation of the Golgi complex, and formation of multilamellar bodies and vesicles of the lysosomal type. In contrast to neuronal alterations, no delay in synaptogenesis or onset of myelination was observed based upon the absence of significant morphological changes in synapses and myelin sheaths. Using this tissue culture model it could be confirmed that prenatal exposure to irradiation, even at low doses, induces specific morphological changes in the brain.

  6. Vortioxetine promotes early changes in dendritic morphology compared to fluoxetine in rat hippocampus.

    PubMed

    Chen, Fenghua; du Jardin, Kristian Gaarn; Waller, Jessica A; Sanchez, Connie; Nyengaard, Jens R; Wegener, Gregers

    2016-02-01

    Preclinical studies reveal that the multimodal antidepressant vortioxetine enhances long-term potentiation and dendritic branching compared to a selective serotonin reuptake inhibitor (SSRI). In the present study, we investigated vortioxetine׳s effects on spines and dendritic morphology in rat hippocampus at two time points compared to the SSRI, fluoxetine. Rats were dosed for 1 and 4 weeks with vortioxetine and fluoxetine at doses relevant for antidepressant activity. Dendritic morphology of pyramidal neurons (i.e., dendritic length, dendritic branch, spine number and density, and Sholl analysis) was examined in Golgi-stained sections from hippocampal CA1. After 1 week of treatment, vortioxetine significantly increased spine number (apical and basal dendrites), spine density (only basal), dendritic length (only apical), and dendritic branch number (apical and basal), whereas fluoxetine had no effect. After 4 weeks of treatment, vortioxetine significantly increased all measures of dendritic spine morphology as did fluoxetine except for spine density of basal dendrites. The number of intersections in the apical and basal dendrites was also significantly increased for both treatments after 4 weeks compared to control. In addition, 4 weeks of vortioxetine treatment, but not fluoxetine, promoted a decrease in spine neck length. In conclusion, 1-week vortioxetine treatment induced changes in spine number and density and dendritic morphology, whereas an equivalent dose of fluoxetine had no effects. Decreased spine neck length following 4-week vortioxetine treatment suggests a transition to mature spine morphology. This implies that vortioxetine׳s effects on spine and dendritic morphology are mediated by mechanisms that go beyond serotonin reuptake inhibition. PMID:26711685

  7. Morphological changes due to tsunami impact: Numerical modelling of sediments transport and deposit at Tangier - Morocco

    NASA Astrophysics Data System (ADS)

    Ramalho, Inês; Omira, Rachid; Baptista, Maria Ana; El Moussaoui, Said; Najib Zaghloul, Mohamed

    2016-04-01

    Coastal areas in the North of Morocco are at risk of tsunami inundation. Overland tsunami propagation leads to widespread and dramatic changes in coastal morphology due to sediments erosion, transport and deposition processes. Tsunami sediments transport and morphological changes must take into consideration bed-load and suspended load transport of non-cohesive sediments and suspended load of cohesive sediments. Numerical calculation of suspended sediment transport/deposition is performed by solving the advection-diffusion equations for the suspended sediment, where the velocities are obtained from the hydrodynamic modelling. In this study, we assess the morphological changes under tsunami impact at the Bay of Tangier-Morocco. We use a coupled hydrodynamic and morpho-dynamic numerical code, based on two open sources codes: COMCOT and Xbeach, to simulate the tsunami impact and the associated sediments transport and deposition. COMCOT solves the shallow water equations to calculate the inundation characteristics (flow depth and velocity), while Xbeach allows solving the advection-diffusion equations to determine the amount of sediments eroded, transported and deposed. The results of this study are presented in terms of maps displaying the amount of sediments eroded, transported and deposed at the bay of Tangier following a tsunami similar to the 1755 Lisbon event. We find that the bay of Tangier is vulnerable to morphological changes under tsunami threat coming from SW Iberia margin. This work is supported by the EU project ASTARTE - Assessment, Strategy And Risk Reduction for Tsunamis in Europe, Grant 603839, 7th FP (ENV.2013,6.4-3).

  8. Anchoring Ethinylestradiol Induced Gene Expression Changes with Testicular Morphology and Reproductive Function in the Medaka

    PubMed Central

    Miller, Hilary D.; Clark, Bryan W.; Hinton, David E.; Whitehead, Andrew; Martin, Stan; Kwok, Kevin W.; Kullman, Seth W.

    2012-01-01

    Environmental estrogens are ubiquitous in the environment and can cause detrimental effects on male reproduction. In fish, a multitude of effects from environmental estrogens have been observed including altered courting behavior and fertility, sex reversal, and gonadal histopathology. However, few studies in fish assess the impacts of estrogenic exposure on a physiological endpoint, such as reproduction, as well as the associated morphologic response and underlying global gene expression changes. This study assessed the implications of a 14 day sub-chronic exposure of ethinylestradiol (EE2; 1.0 or 10.0 µg/L EE2) on male medaka fertility, testicular histology and testicular gene expression. The findings demonstrate that a 14 day exposure to EE2 induced impaired male reproductive capacity and time- and dose-dependent alterations in testicular morphology and gene expression. The average fertilization rate/day following the exposure for control, 1.0 and 10.0 µg/L EE2 was 91.3% (±4.4), 62.8% (±8.3) and 28.8% (±5.8), respectively. The testicular morphologic alterations included increased germ cell apoptosis, decreased germinal epithelium and thickening of the interstitium. These changes were highly associated with testicular gene expression changes using a medaka-specific microarray. A pathway analysis of the differentially expressed genes emphasized genes and pathways associated with apoptosis, cell cycle and proliferation, collagen production/extracellular matrix organization, hormone signaling, male reproduction and protein ubiquitination among others. These findings highlight the importance of anchoring global gonadal gene expression changes with morphology and ultimately with tissue/organ function. PMID:23300682

  9. Change dynamics of RBC morphology after injection glucose for diabetes by diffraction phase microscope

    NASA Astrophysics Data System (ADS)

    Talaykova, N. A.; Kalyanov, A. L.; Lychagov, V. V.; Ryabukho, V. P.; Malinova, L. I.

    2013-11-01

    Experimental setup of diffraction phase microscope (DPM) with double low-coherence lighting system is presented in the paper. Algorithm of interference picture processing and optical thickness, height, volume and mean cells volume (MCV) of RBC calculating is shown. We demonstrate results of experiments with blood smears and ability of the method to calculate 3D model of the biological cells shape. Investigation change dynamics of RBC morphology after injection glucose for diabetes by DPM is shown in the paper.

  10. Does weather shape rodents? Climate related changes in morphology of two heteromyid species

    NASA Astrophysics Data System (ADS)

    Wolf, Mosheh; Friggens, Michael; Salazar-Bravo, Jorge

    2009-01-01

    Geographical variation in morphometric characters in heteromyid rodents has often correlated with climate gradients. Here, we used the long-term database of rodents trapped in the Sevilleta National Wildlife Refuge in New Mexico, USA to test whether significant annual changes in external morphometric characters are observed in a region with large variations in temperature and precipitation. We looked at the relationships between multiple temperature and precipitation variables and a number of morphological traits (body mass, body, tail, hind leg, and ear length) for two heteromyid rodents, Dipodomys merriami and Perognathus flavescens. Because these rodents can live multiple years in the wild, the climate variables for the year of the capture and the previous 2 years were included in the analyses. Using multiple linear regressions, we found that all of our morphometric traits, with the exception of tail length in D. merriami, had a significant relationship with one or more of the climate variables used. Our results demonstrate that effects of climate change on morphological traits occur over short periods, even in noninsular mammal populations. It is unclear, though, whether these changes are the result of morphological plasticity or natural selection.

  11. Linckosides enhance proliferation and induce morphological changes in human olfactory ensheathing cells.

    PubMed

    Tello Velasquez, Johana; Yao, Rebecca-Qing; Lim, Filip; Han, Chunguang; Ojika, Makoto; Ekberg, Jenny A K; Quinn, Ronald J; John, James A St

    2016-09-01

    Linckosides are members of the steroid glycoside family isolated from the starfish Linckia laevigata. These natural compounds have notable neuritogenic activity and synergistic effects on NGF-induced neuronal differentiation of PC12 cells. Neurogenic factors or molecules that are able to mimic their activities are known to be involved in the survival, proliferation and migration of neurons and glial cells; however how glial cells respond to specific neurogenic molecules such as linckosides has not been investigated. This study aimed to examine the effect of three different linckosides (linckoside A, B and granulatoside A) on the morphological properties, proliferation and migration of human olfactory ensheathing cells (hOECs). The proliferation rate after all the treatments was higher than control as detected by MTS assay. Additionally, hOECs displayed dramatic morphological changes characterized by a higher number of processes after linckoside treatment. Interestingly changes in microtubule organization and expression levels of some early neuronal markers (GAP43 and βIII-tubulin) were also observed. An increase in the phosphorylation of ERK 1/2 after addition of the compounds suggests that this pathway may be involved in the linckoside-mediated effects particularly those related to morphological changes. These results are the first description of the stimulating effects of linckosides on hOECs and raise the potential for this natural compound or its derivatives to be used to regulate and enhance the therapeutic properties of OECs, particularly for cell transplantation therapies. PMID:27343824

  12. COLLAGEN MUTATION CAUSES CHANGES OF THE MICRODAMAGE MORPHOLOGY IN BONE OF AN OI MOUSE MODEL

    PubMed Central

    Dong, X. Neil; Zoghi, Mahyar; Ran, Qitao; Wang, Xiaodu

    2010-01-01

    Previous studies have postulated that ultrastructural changes may alter the pattern and capacity of microdamage accumulation in bone. Using an osteogenesis imperfecta (OI) mouse model, this study was performed to investigate the correlation of collagen mutation with the microdamage morphology and the associated brittleness of bone. In this study, femurs from mild OI and wild type mice were fatigued under four-point bending to create microdamage in the specimens. Then, the microdamage morphology of these specimens was examined using the bulk-staining technique with basic fuchsin. Similar with the results of previous studies, it was observed that linear microcracks were formed more easily in compression, whereas diffuse damage was induced more readily in tension for both wild-type and mild-type mice. However, less diffuse damage was found in the tensile side of mild OI mouse femurs (collagen mutation) compared with those of wild type mice, showing that the microdamage morphology is correlated to the brittleness of bone. The results of this study provide direct evidence that supports the prediction made by the previous numerical simulation studies, suggesting that microdamage morphology in bone is significantly correlated with the integrity of the collagen phase. PMID:20736092

  13. Collagen mutation causes changes of the microdamage morphology in bone of an OI mouse model.

    PubMed

    Dong, X Neil; Zoghi, Mahyar; Ran, Qitao; Wang, Xiaodu

    2010-12-01

    Previous studies have postulated that ultrastructural changes may alter the pattern and capacity of microdamage accumulation in bone. Using an osteogenesis imperfecta (OI) mouse model, this study was performed to investigate the correlation of collagen mutation with the microdamage morphology and the associated brittleness of bone. In this study, femurs from mild OI and wild type mice were fatigued under four-point bending to create microdamage in the specimens. Then, the microdamage morphology of these specimens was examined using the bulk-staining technique with basic fuchsin. Similar with the results of previous studies, it was observed that linear microcracks were formed more easily in compression, whereas diffuse damage was induced more readily in tension for both wild-type and mild-type mice. However, less diffuse damage was found in the tensile side of mild OI mouse femurs (collagen mutation) compared with those of wild type mice, showing that the microdamage morphology is correlated to the brittleness of bone. The results of this study provide direct evidence that supports the prediction made by the previous numerical simulation studies, suggesting that microdamage morphology in bone is significantly correlated with the integrity of the collagen phase. PMID:20736092

  14. Microtubule inhibitors block the morphological changes induced in Drosophila blood cells by a parasitoid wasp factor.

    PubMed

    Rizki, R M; Rizki, T M

    1990-03-15

    The shape change of Drosophila melanogaster blood cells (lamellocytes) from discoidal to bipolar that is caused by a factor from the female parasitoid Leptopilina heterotoma is blocked by the tubulin inhibitors vinblastine and vincristine in vitro. The actin inhibitor, cytochalasin B, causes arborization of Drosophila lamellocytes and acts synergistically with the wasp factor to alter lamellocyte morphology. Lamellocyte aborization induced by cytochalasin B is blocked by simultaneous treatment with vinblastine. These observations indicate that the changes in lamellocyte shape induced by both the wasp factor and cytochalasin B require microtubule assembly. PMID:2311722

  15. Neurobiological origin of spurious brain morphological changes: A quantitative MRI study

    PubMed Central

    Lorio, Sara; Kherif, Ferath; Ruef, Anne; Melie‐Garcia, Lester; Frackowiak, Richard; Ashburner, John; Helms, Gunther

    2016-01-01

    Abstract The high gray‐white matter contrast and spatial resolution provided by T1‐weighted magnetic resonance imaging (MRI) has made it a widely used imaging protocol for computational anatomy studies of the brain. While the image intensity in T1‐weighted images is predominantly driven by T1, other MRI parameters affect the image contrast, and hence brain morphological measures derived from the data. Because MRI parameters are correlates of different histological properties of brain tissue, this mixed contribution hampers the neurobiological interpretation of morphometry findings, an issue which remains largely ignored in the community. We acquired quantitative maps of the MRI parameters that determine signal intensities in T1‐weighted images (R 1 (=1/T1), R 2*, and PD) in a large cohort of healthy subjects (n = 120, aged 18–87 years). Synthetic T1‐weighted images were calculated from these quantitative maps and used to extract morphometry features—gray matter volume and cortical thickness. We observed significant variations in morphometry measures obtained from synthetic images derived from different subsets of MRI parameters. We also detected a modulation of these variations by age. Our findings highlight the impact of microstructural properties of brain tissue—myelination, iron, and water content—on automated measures of brain morphology and show that microstructural tissue changes might lead to the detection of spurious morphological changes in computational anatomy studies. They motivate a review of previous morphological results obtained from standard anatomical MRI images and highlight the value of quantitative MRI data for the inference of microscopic tissue changes in the healthy and diseased brain. Hum Brain Mapp 37:1801–1815, 2016. © 2016 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:26876452

  16. Morphological, hydrological, biogeochemical and ecological changes and challenges in river restoration - the Thur River case study

    NASA Astrophysics Data System (ADS)

    Schirmer, M.; Luster, J.; Linde, N.; Perona, P.; Mitchell, E. A. D.; Barry, D. A.; Hollender, J.; Cirpka, O. A.; Schneider, P.; Vogt, T.; Radny, D.; Durisch-Kaiser, E.

    2014-06-01

    River restoration can enhance river dynamics, environmental heterogeneity and biodiversity, but the underlying processes governing the dynamic changes need to be understood to ensure that restoration projects meet their goals, and adverse effects are prevented. In particular, we need to comprehend how hydromorphological variability quantitatively relates to ecosystem functioning and services, biodiversity as well as ground- and surface water quality in restored river corridors. This involves (i) physical processes and structural properties, determining erosion and sedimentation, as well as solute and heat transport behavior in surface water and within the subsurface; (ii) biogeochemical processes and characteristics, including the turnover of nutrients and natural water constituents; and (iii) ecological processes and indicators related to biodiversity and ecological functioning. All these aspects are interlinked, requiring an interdisciplinary investigation approach. Here, we present an overview of the recently completed RECORD (REstored CORridor Dynamics) project in which we combined physical, chemical, and biological observations with modeling at a restored river corridor of the perialpine Thur River in Switzerland. Our results show that river restoration, beyond inducing morphologic changes that reshape the river bed and banks, triggered complex spatial patterns of bank infiltration, and affected habitat type, biotic communities and biogeochemical processes. We adopted an interdisciplinary approach of monitoring the continuing changes due to restoration measures to address the following questions: How stable is the morphological variability established by restoration? Does morphological variability guarantee an improvement in biodiversity? How does morphological variability affect biogeochemical transformations in the river corridor? What are some potential adverse effects of river restoration? How is river restoration influenced by catchment-scale hydraulics

  17. Surfactant-directed synthesis of silver nanorods and characteristic spectral changes occurred by their morphology evolution

    NASA Astrophysics Data System (ADS)

    Zhang, Wen; Hu, Guansong; Zhang, Wanzhong; Qiao, Xueliang; Wu, Kai; Chen, Qingyuan; Cai, Yuchun

    2014-11-01

    Silver nanorods with different polydispersity were synthesized in the cetyltrimethylammonium bromide (CTAB) rod-shaped micelles by inducing the orientation growth of silver seeds and adjusting the volumes of CTAB. The reaction for the formation of silver nanorods had basically finished in 10 min. A suitable volume of CTAB (i.e., 15.0 mL of 0.1 M CTAB) is beneficial to obtain high-quality silver nanorods in the given reaction system. That is, the volume of added CTAB is a key factor to determine the polydispersity of the formed nanorods. The aging time plays a critical role in the morphology evolution of silver nanorods due to the oxidation of silver nanorods with Br-, O2 and the Ostwald ripening of the nanoparticles. As a result, the characteristic spectral changes occurred due to the morphology evolution of silver nanorods. The ablation in the top ends of the longer nanorods is often accompanied by the growth of some shorter nanorods and nanospheres. The size distribution of silver nanorods might be more uniform in the early aging stage. All the nanorods in the colloidal solution should turn into the near-spherical nanoparticles with larger sizes and thus the characteristic absorption should change to single peak centered at about 400 nm. Based on the research results, mathematical models are proposed for explaining the formation and morphology changes of silver nanorods. The morphology evolution of silver nanorods may be important and can be used as a reference for preparing silver nanorods, nanowires and other anisotropic nanomaterials.

  18. Morphological and physiological changes during reproduction and their relationships to reproductive performance in a capital breeder.

    PubMed

    Stahlschmidt, Zachary R; Lourdais, Olivier; Lorioux, Sophie; Butler, Michael W; Davis, Jon R; Salin, Karine; Voituron, Yann; DeNardo, Dale F

    2013-01-01

    Current reproductive effort typically comes at a cost to future reproductive value by altering somatic function (e.g., growth or self-maintenance). Furthermore, effects of reproduction often depend on both fecundity and stage of reproduction, wherein allocation of resources into additional offspring and/or stages of reproduction results in increased costs. Despite these widely accepted generalities, interindividual variation in the effects of reproduction is common-yet the proximate basis that allows some individuals to mitigate these detrimental effects is unclear. We serially measured several variables of morphology (e.g., musculature) and physiology (e.g., antioxidant defenses) in female Children's pythons (Antaresia childreni) throughout reproduction to examine how these traits change over the course of reproduction and whether certain physiological traits are associated with reduced effects of reproduction in some individuals. Reproduction in this capital breeder was associated with changes in both morphology and physiology, but only morphological changes varied with fecundity and among specific reproductive stages. During reproduction, we detected negative relationships between morphology and self-maintenance (e.g., increased muscle allocation to reproduction was related to reduced immune function). Additionally, females that allocated resources more heavily into current reproduction also did so during future reproduction, and these females assimilated resources more efficiently, experienced reduced detriments to self-maintenance (e.g., lower levels of oxidative damage and glucocorticoids) during reproduction, and produced clutches with greater hatching success. Our results suggest that interindividual variation in specific aspects of physiology (assimilation efficiency and oxidative status) may drive variation in reproductive performance. PMID:23799834

  19. Neurobiological origin of spurious brain morphological changes: A quantitative MRI study.

    PubMed

    Lorio, Sara; Kherif, Ferath; Ruef, Anne; Melie-Garcia, Lester; Frackowiak, Richard; Ashburner, John; Helms, Gunther; Lutti, Antoine; Draganski, Bodgan

    2016-05-01

    The high gray-white matter contrast and spatial resolution provided by T1-weighted magnetic resonance imaging (MRI) has made it a widely used imaging protocol for computational anatomy studies of the brain. While the image intensity in T1-weighted images is predominantly driven by T1, other MRI parameters affect the image contrast, and hence brain morphological measures derived from the data. Because MRI parameters are correlates of different histological properties of brain tissue, this mixed contribution hampers the neurobiological interpretation of morphometry findings, an issue which remains largely ignored in the community. We acquired quantitative maps of the MRI parameters that determine signal intensities in T1-weighted images (R1 (=1/T1), R2 *, and PD) in a large cohort of healthy subjects (n = 120, aged 18-87 years). Synthetic T1-weighted images were calculated from these quantitative maps and used to extract morphometry features-gray matter volume and cortical thickness. We observed significant variations in morphometry measures obtained from synthetic images derived from different subsets of MRI parameters. We also detected a modulation of these variations by age. Our findings highlight the impact of microstructural properties of brain tissue-myelination, iron, and water content-on automated measures of brain morphology and show that microstructural tissue changes might lead to the detection of spurious morphological changes in computational anatomy studies. They motivate a review of previous morphological results obtained from standard anatomical MRI images and highlight the value of quantitative MRI data for the inference of microscopic tissue changes in the healthy and diseased brain. Hum Brain Mapp 37:1801-1815, 2016. © 2016 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:26876452

  20. Temporal morphological changes in the Imhotep region of comet 67P/Churyumov-Gerasimenko

    NASA Astrophysics Data System (ADS)

    Groussin, O.; Sierks, H.; Barbieri, C.; Lamy, P.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.; A'Hearn, M. F.; Auger, A.-T.; Barucci, M. A.; Bertaux, J.-L.; Bertini, I.; Besse, S.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; El-Maarry, M. R.; Fornasier, S.; Fulle, M.; Gutiérrez, P. J.; Güttler, C.; Hviid, S.; Ip, W.-H.; Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm, J. R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez Moreno, J. J.; Lowry, S.; Marchi, S.; Marzari, F.; Massironi, M.; Mottola, S.; Naletto, G.; Oklay, N.; Pajola, M.; Pommerol, A.; Thomas, N.; Toth, I.; Tubiana, C.; Vincent, J.-B.

    2015-11-01

    Aims: We report on the first major temporal morphological changes observed on the surface of the nucleus of comet 67P/Churyumov-Gerasimenko in the smooth terrains of the Imhotep region. Methods: We used images of the OSIRIS cameras onboard Rosetta to follow the temporal changes from 24 May 2015 to 11 July 2015. Results: The morphological changes observed on the surface are visible in the form of roundish features that are growing in size from a given location in a preferential direction at a rate of 5.6-8.1 × 10-5 m s-1 during the observational period. The location where the changes started and the contours of the expanding features are bluer than the surroundings, which suggests that ices (H2O and/or CO2) are exposed on the surface. However, sublimation of ices alone is not sufficient to explain the observed expanding features. No significant variations in the dust activity pattern are observed during the period of changes.

  1. Spatio-Temporal Pattern Analysis for Regional Climate Change Using Mathematical Morphology

    NASA Astrophysics Data System (ADS)

    Das, M.; Ghosh, S. K.

    2015-07-01

    Of late, significant changes in climate with their grave consequences have posed great challenges on humankind. Thus, the detection and assessment of climatic changes on a regional scale is gaining importance, since it helps to adopt adequate mitigation and adaptation measures. In this paper, we have presented a novel approach for detecting spatio-temporal pattern of regional climate change by exploiting the theory of mathematical morphology. At first, the various climatic zones in the region have been identified by using multifractal cross-correlation analysis (MF-DXA) of different climate variables of interest. Then, the directional granulometry with four different structuring elements has been studied to detect the temporal changes in spatial distribution of the identified climatic zones in the region and further insights have been drawn with respect to morphological uncertainty index and Hurst exponent. The approach has been evaluated with the daily time series data of land surface temperature (LST) and precipitation rate, collected from Microsoft Research - Fetch Climate Explorer, to analyze the spatio-temporal climatic pattern-change in the Eastern and North-Eastern regions of India throughout four quarters of the 20th century.

  2. Exercise prevents β-aminopropionitrile-induced morphological changes to type I collagen in murine bone

    PubMed Central

    Hammond, Max A; Wallace, Joseph M

    2015-01-01

    This study evaluated the effects of reduced enzymatic crosslinking, exercise and the ability of exercise to prevent the deleterious impact of reduced crosslinking on collagen D-spacing. Eight-week-old female mice were divided into four weight-matched groups receiving daily injections of either phosphate-buffered saline (PBS) or 300 mg kg−1 β-aminopropionitrile (BAPN) while undergoing normal cage activity (Sed) or 30 min per day of treadmill exercise (Ex) for 21 consecutive days. BAPN caused a downward shift in the D-spacing distribution in Sed BAPN compared with Sed PBS (P<0.001) but not in Ex BAPN (P=0.429), indicating that exercise can prevent changes in collagen morphology caused by BAPN. Exercise had no effect on D-spacing in PBS control mice (P=0.726), which suggests that exercise-induced increases in lysyl oxidase may be a possible mechanism for preventing BAPN-induced changes in D-spacing. The D-spacing changes were accompanied by an increase in mineral crystallinity/maturity due to the main effect of BAPN (P=0.016). However, no changes in nanoindentation, reference point indentation or other Raman spectroscopy parameters were observed. The ability of exercise to rescue BAPN-driven changes in collagen morphology necessitates further research into the use of mechanical stimulation as a preventative therapy for collagen-based diseases. PMID:25798234

  3. Chemical and morphological changes in human dentin after Er:YAGlaser irradiation: EDS and SEM analysis.

    PubMed

    Contreras-Arriaga, Belinda; Rodríguez-Vilchis, Laura Emma; Contreras-Bulnes, Rosalía; Olea-Mejìa, Oscar Fernando; Scougall-Vilchis, Rogelio José; Centeno-Pedraza, Claudia

    2015-11-01

    Sixty samples of human dentin were divided into six groups (n = 10) and were irradiated with Er:YAG laser at 100 mJ-19.9 J/cm(2), 150 mJ-29.8 J/cm(2), 100 mJ-35.3 J/cm(2), 150 mJ-53.0 J/cm(2), 200 mJ-70.7 J/cm(2), and 250 mJ-88.5 J/cm(2), respectively, at 7 Hz under a water spray. The atomic percentages of carbon, oxygen, magnesium, calcium, and phosphorus and the Ca-to-P molar ratio on the dentin were determined by energy dispersive X-ray spectroscopy. The morphological changes were observed using scanning electron microscopy. A paired t-test was used in statistical analysis before and after irradiation, and a one-way ANOVA was performed (P ≤ 0.05). The atomic percent of C tended to decrease in all of the groups after irradiation with statistically significant differences, O and Mg increased with significant differences in all of the groups, and the Ca-to-P molar ratio increased in groups IV, V, and VI, with statistically significant differences between groups II and VI. All the irradiated samples showed morphological changes. Major changes in the chemical composition of dentin were observed in trace elements. A significant increase in the Ca-to-P ratio was observed in the higher energy density groups. Morphological changes included loss of smear layer with exposed dentinal tubules. The changes produced by the different energy densities employed could have clinical implications, additional studies are required to clarify them. PMID:26397964

  4. Transcriptional and morphological changes in the transition from mycetophagous to phytophagous phase in the plant-parasitic nematode Bursaphelenchus xylophilus.

    PubMed

    Tsai, Isheng J; Tanaka, Ryusei; Kanzaki, Natsumi; Akiba, Mitsuteru; Yokoi, Toshiro; Espada, Margarida; Jones, John T; Kikuchi, Taisei

    2016-01-01

    Drastic physiological and morphological changes in parasites are crucial for the establishment of a successful infection. The nematode Bursaphelenchus xylophilus is the pathogenic agent of pine wilt disease, and little is known about the physiology and morphology in this nematode at the initial stage of infection. In this study, we devised an infection system using pine stem cuttings that allowed us to observe transcriptional and morphological changes in the host-infecting phytophagous phase. We found that 60 genes enriched in xenobiotic detoxification were up-regulated in two independent post-inoculation events, whereas down-regulation was observed in multiple members of collagen gene families. After 48 h of inoculation, the tails in some of the adult females exposed to the host changed in morphology. These results suggest that B. xylophilus may change its physiology and morphology to protect itself and to adapt to the host pine wood environment. PMID:25831996

  5. Cytological findings of appendiceal mixed adenoneuroendocrine carcinoma in pleural effusion: Morphological changes evident after metastasis.

    PubMed

    Tonooka, Akiko; Oda, Ken-Ichi; Hayashi, Mamoru; Sakazume, Ko-Ichi; Tanaka, Hiroki; Kaburaki, Kyo-Hei; Uekusa, Toshimasa

    2015-07-01

    Goblet cell carcinoid (GCC) of the appendix is now regarded as a malignant tumor, and mixed adenoneuroendocrine carcinoma (MANEC) is a carcinoma progressing from GCC. We describe a man initially diagnosed with GCC of the appendix who died 4 years after diagnosis. Pleural fluid due to metastasis was noted in the terminal phase. Histological findings of the initial tumor indicated that cells with signet-ring morphology were predominant, but the cytological morphology of the fluid was more atypical, making it difficult to diagnose as metastatic GCC by cellular morphology alone. The cells in the pleural fluid were immunopositive for synaptophysin, which was compatible with GCC, but p53 and ki67 staining indicated that the metastatic tumor was more aggressive. These findings suggested a final diagnosis of poorly differentiated adenocarcinoma-type MANEC, which we define as a tumor with typical GCC characteristics and foci that cannot be distinguished from a poorly differentiated adenocarcinoma. This case, which we believe is reported here for the first time, indicates the cytological features of GCC cells may change at metastatic sites to be more atypical and aggressive as the tumor progresses, and these changes should be considered in diagnosis. PMID:25425263

  6. Cell wall staining with Trypan blue enables quantitative analysis of morphological changes in yeast cells

    PubMed Central

    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. PMID:25717323

  7. Morphological changes at Vellar estuary, India--impact of the December 2004 tsunami.

    PubMed

    Pari, Y; Ramana Murthy, M V; Jaya Kumar, S; Subramanian, B R; Ramachandran, S

    2008-10-01

    Coastal subsystems formed by interaction of various processes, impacted by natural hazards like tsunami and storms, pose irreversible morphological changes. Vellar estuary, located on the southeast coast of India, with huge sand dunes (of 3-6m height and spread to 560 ha) and barrier islands, has undergone extensive morphological changes due to the giant Indian Ocean tsunami that occurred on 26th December 2004. The damage caused by the tsunami has been quantified using extensive field data collected during pre- and post-tsunami periods through Real Time Kinematic GPS (for mapping coastal features and beach profiles) and Geographic Information System (GIS) couple. The tsunami with a wave height as high as 4 m not only inundated the entire coastal land up to a maximum of 2 km but also eroded the sand dunes and deposited the eroded material at the inlet, which ultimately formed as a vast tidal flat spread over 31 ha. The estuary has suffered immensely due to the tsunami especially in terms of (i) loss of natural protection barriers (sand dunes), which made this coastal area more vulnerable to storm attack, and (ii) shallowness of inlet creating hindrance to navigation of fishing vessels. Based on the observations made at Vellar coast and past recovery experiences of tsunami/hurricanes elsewhere in the world, we contend that the morphological loss might take at least two annual cycles to regain its original form and the rebuilding of sand dunes may even take a decade. PMID:17574726

  8. Water Masers in W43A: Early Morphological Changes of a Future Planetary Nebula

    NASA Astrophysics Data System (ADS)

    Chong, Sze-Ning; Imai, Hiroshi; Diamond, Philip J.

    2015-05-01

    We present the distribution patterns of H2O maser features in the “water fountain” source (WF) W43A and show that they are closely related to the early morphological changes in a planetary nebula (PN). Using the Very Long Baseline Array, we have detected H2O maser features in W43A in 13 epochs across \\gt 10 yr. W43A is the only WF that has been observed for over a decade. We introduce a new cavity model scenario—a halo with a bipolar evacuated volume that has a partially enhanced wall—and compare it with the “traditional” precessing jet model particularly in terms of explaining the bow-shaped distribution patterns of H2O maser features in the most recent epochs and their temporal evolution. Long-term observations show that the distribution patterns require more than a single jet to form. Moreover, we have identified six groups of H2O maser features at both the redshifted and blueshifted sides with point symmetry. The six groups are believed to correspond to periodic mass profiles in the envelope and have recorded the mass-loss history. Together with a geometric similarity to the mid-infrared morphology of W43A, the results suggest that H2O masers can be used to trace the inner morphology and rapid temporal changes in evolved stars, especially where the PN shaping has just started.

  9. Long-term morphological changes in Welsh regulated rivers under distinct impoundment configuration

    NASA Astrophysics Data System (ADS)

    Vericat, D.; Batalla, R. J.; Gibbins, C.; Brasington, J.

    2009-04-01

    Dams cut the continuity of sediment and water transfer worldwide. Magnitude and frequency of competent events are reduced while important percentages of the sediment load of regulated rivers are trapped in reservoirs. These alterations cause morphological changes on downstream reaches and coastline ecosystems and may create important effects on river's habitat. The analyses of such alterations are relevant for water and sediment management purposes in regulated rivers and, in the case of the European Union, may inform actions to restore geomorphic integrity of fluvial systems under the Water Framework Directive. In this work we present the preliminary results of a research project with the aim to study long-term morphological alterations in four regulated rivers under different impounded configuration in Wales, United Kingdom. Impoundment configuration refers to the number and relative position of dams along a stream course of a channel network. The project involve (i) state-of-the-art high resolution topographic surveys upstream and downstream from dams acquired by means of RTK-GPS and Terrestrial Laser Scanning, (ii) determination of the morphological changes downstream from dams since they were commissioned using historical maps and aerial photographs, (iii) ground-based characterization of surface and subsurface bed material, (iv) hydrological modelling to asses the effects of dams on flow regimes and flood magnitude and frequency and (v) hydraulic modelling to study bed stability downstream from the dams.

  10. Mechanics of water collection in plants via morphology change of conical hairs

    NASA Astrophysics Data System (ADS)

    Ito, Fuyu; Komatsubara, Satoshi; Shigezawa, Naoki; Morikawa, Hideaki; Murakami, Yasushi; Yoshino, Katsumi; Yamanaka, Shigeru

    2015-03-01

    In an arid area like the Namib Desert, plants and animals obtain moisture needed for life from mist in the air. There, some plants have hairs or fibrous structures on their leaf surface that reportedly collect fresh water from the air. We examined the morphology and function of leaf hairs of plants during water collection under different circumstances. We studied the water collecting mechanics of several plants having fibrous hairs on their leaves: tomato, balsam pear, Berkheya purpurea, and Lychnis sieboldii. This plant was selected for detailed investigation as a model because this plant originated from dry grassland near Mount Aso in Kyusyu, Japan. We found a unique feature of water collection and release in this plant. The cone-shaped hairs having inner microfibers were reversibly converted to crushed plates that were twisted perpendicularly in dry conditions. Microfibers found in the hairs seem to be responsible for water storage and release. Their unique reciprocal morphological changes, cone-shaped hairs transformed into perpendicularly twisted shapes, depend on the moisture level in the air, and water stored during wet external conditions was released onto the leaf in drier conditions. These morphological changes were recorded as a movie. Simulations explained the formation of the twisted structure. In theoretical analyses, twisted structures were found to give higher mechanical strength. Similar phenomena were found in the other plants described above. These findings pave the way to new bioinspired technology for alleviating global water shortages.

  11. Temporal morphological changes at the surface of comet 67P/Churyumov-Gerasimenko

    NASA Astrophysics Data System (ADS)

    Groussin, Olivier; Sierks, H.; Barbieri, C.; Lamy, P.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.

    2015-11-01

    A key scientific question, to understand how comets work and whether they still contain pristine materials at or near their surface, is to understand how the nucleus is changing with time and to which extent activity modifies its surface. Rosetta, which has been orbiting comet 67P/Churyumov-Gerasimenko since August 2014, offers a unique opportunity to tackle this fundamental question. Here, we report on temporal morphological changes detected on the surface of the nucleus of comet 67P by the OSIRIS cameras. Changes have been detected in several regions and in particular in the Imhotep region, where they are visible in the form of roundish features that are growing in size from a given location in a preferential direction. Terrains bluer than the surroundings appear during changes, suggesting the presence of (water) ice exposed on the surface.

  12. Prediction of solvent-induced morphological changes of polyelectrolyte diblock copolymer micelles.

    PubMed

    Li, Nan K; Fuss, William H; Tang, Lei; Gu, Renpeng; Chilkoti, Ashutosh; Zauscher, Stefan; Yingling, Yaroslava G

    2015-11-14

    Self-assembly processes of polyelectrolyte block copolymers are ubiquitous in industrial and biological processes; understanding their physical properties can also provide insights into the design of polyelectrolyte materials with novel and tailored properties. Here, we report systematic analysis on how the ionic strength of the solvent and the length of the polyelectrolyte block affect the self-assembly and morphology of the polyelectrolyte block copolymer materials by constructing a salt-dependent morphological phase diagram using an implicit solvent ionic strength (ISIS) method for dissipative particle dynamics (DPD) simulations. This diagram permits the determination of the conditions for the morphological transition into a specific shape, namely vesicles or lamellar aggregates, wormlike/cylindrical micelles, and spherical micelles. The scaling behavior for the size of spherical micelles is predicted, in terms of radius of gyration (R(g,m)) and thickness of corona (Hcorona), as a function of solvent ionic strength (c(s)) and polyelectrolyte length (NA), which are R(g,m) ∼ c(s)(-0.06)N(A)(0.54) and Hcorona ∼ c(s)(-0.11)N(A)(0.75). The simulation results were corroborated through AFM and static light scattering measurements on the example of the self-assembly of monodisperse, single-stranded DNA block-copolynucleotides (polyT50-b-F-dUTP). Overall, we were able to predict the salt-responsive morphology of polyelectrolyte materials in aqueous solution and show that a spherical-cylindrical-lamellar change in morphology can be obtained through an increase in solvent ionic strength or a decrease of polyelectrolyte length. PMID:26315065

  13. Sustained morphologic changes to the shoreface related to Hurricane Sandy: Fire Island, NY

    NASA Astrophysics Data System (ADS)

    Hapke, C. J.; Nelson, T. R.

    2014-12-01

    A variety of topographic and photographic data have revealed widespread impacts to the subaerial portion of the beach system during Hurricane Sandy in 2012 - from beach erosion to barrier island breaching. However, less is known about impacts to the offshore environment. In order to examine a more comprehensive response of the active beach system to Hurricane Sandy, we quantify morphologic changes to the shoreface using bathymetric data along the length of Fire Island, NY. Airborne bathymetric lidar data, collected two days before Sandy made landfall, are used as a pre-storm baseline. Morphologic changes are measured using field surveyed GPS profiles collected along a limited portion of western Fire Island two months following Sandy and along the length of the island one year after Sandy. The offshore extent of the data is variable and analyses are constrained by the resolving ability of the lidar sensor, which typically achieved penetration to depths of 6-8m. The surfzone morphology was extensively impacted by Hurricane Sandy and continued to evolve during subsequent winter storms. As is typical during large storm events, the outer bar moved offshore during Sandy. A year after the storm, however, the bar remains further offshore than it was prior to Sandy, resulting in a widened surfzone. Both the subaerial and submarine portions of the beach system lost considerable volumes of sand. The majority of the loss below mean high water (MHW) is in the surfzone, concentrated in the trough immediately landward of the outer bar and generally in the pre-storm location of the outer bar. The trough not only deepened in response to Sandy, but in many locations continued to deepen over the course of the following year, with an average change of more than a meter. The average volume of the shoreface seaward of the bar increased, which is attributed to the seaward translation of the outer bar and additional offshore transport and deposition of material from the inner surfzone

  14. Morphological and dietary responses of chipmunks to a century of climate change.

    PubMed

    Walsh, Rachel E; Aprígio Assis, Ana Paula; Patton, James L; Marroig, Gabriel; Dawson, Todd E; Lacey, Eileen A

    2016-09-01

    Predicting how individual taxa will respond to climatic change is challenging, in part because the impacts of environmental conditions can vary markedly, even among closely related species. Studies of chipmunks (Tamias spp.) in Yosemite National Park provide an important opportunity to explore the reasons for this variation in response. While the alpine chipmunk (T. alpinus) has undergone a significant elevational range contraction over the past century, the congeneric and partially sympatric lodgepole chipmunk (T. speciosus) has not experienced an elevational range shift during this period. As a first step toward identifying the factors underlying this difference in response, we examined evidence for dietary changes and changes in cranial morphology in these species over the past century. Stable isotope analyses of fur samples from modern and historical museum specimens of these species collected at the same localities indicated that signatures of dietary change were more pronounced in T. alpinus, although diet breadth did not differ consistently between the study species. Morphometric analyses of crania from these specimens revealed significant changes in cranial shape for T. alpinus, with less pronounced changes in shape for T. speciosus; evidence of selection on skull morphology was detected for T. alpinus, but not for T. speciosus. These results are consistent with growing evidence that T. alpinus is generally more responsive to environmental change than T. speciosus, but emphasize the complex and often geographically variable nature of such responses. Accordingly, future studies that make use of the taxonomically and spatially integrative approach employed here may prove particularly informative regarding relationships between environmental conditions, range changes, and patterns of phenotypic variation. PMID:26732228

  15. Changes induced by peripheral nerve injury in the morphology and nanomechanics of sensory neurons

    NASA Astrophysics Data System (ADS)

    Benzina, Ouafa; Szabo, Vivien; Lucas, Olivier; Saab, Marie-belle; Cloitre, Thierry; Scamps, Frédérique; Gergely, Csilla; Martin, Marta

    2013-06-01

    Peripheral nerve injury in vivo promotes a regenerative growth in vitro characterized by an improved neurite regrowth. Knowledge of the conditioning injury effects on both morphology and mechanical properties of live sensory neurons could be instrumental to understand the cellular and molecular mechanisms leading to this regenerative growth. In the present study, we use differential interference contrast microscopy, fluorescence microscopy and atomic force microscopy (AFM) to show that conditioned axotomy, induced by sciatic nerve injury, does not increase somatic size of sensory neurons from adult mice lumbar dorsal root ganglia but promotes the appearance of longer and larger neurites and growth cones. AFM on live neurons is also employed to investigate changes in morphology and membrane mechanical properties of somas of conditioned neurons following sciatic nerve injury. Mechanical analysis of the soma allows distinguishing neurons having a regenerative growth from control ones, although they show similar shapes and sizes.

  16. Rapid morphological change in black rats (Rattus rattus) after an island introduction

    PubMed Central

    Byrn, David; Lee, Kashawneda L.Y.; Jackson, Racheal

    2015-01-01

    Rapid morphological change has been shown in rodent populations on islands, including endemic deer mice (Peromyscus maniculatus subspp.) on the California Channel Islands. Surprisingly, most of these changes were towards a smaller size. Black rats were introduced to Anacapa Island in the mid-1800s (probably in 1853) and eradicated in 2001–2002. To assess possible changes in these rats since their introduction, eleven cranial and four standard external measurements were taken from 59 Rattus rattus specimens collected from 1940–2000. All rat cranial traits changed 3.06–10.43% (724–2567 d, 0.06–0.42 h), and all became larger. When considered in haldanes, these changes are among the fastest on record in any organism, and far exceed changes found in other island rodents. These changes were confirmed by MANOVA (Wilk’s λ < 0.0005, Fd.f.15 = 2974.386, P < 0.0005), and all 11 cranial traits significantly fit linear regressions. We speculate that concurrent changes in mice may have been due in part to competition with and/or predation by rats. Future research might evaluate whether the vector of mouse evolution on Anacapa is again changing after rat eradication. PMID:25780765

  17. Rapid morphological change in black rats (Rattus rattus) after an island introduction.

    PubMed

    Pergams, Oliver R W; Byrn, David; Lee, Kashawneda L Y; Jackson, Racheal

    2015-01-01

    Rapid morphological change has been shown in rodent populations on islands, including endemic deer mice (Peromyscus maniculatus subspp.) on the California Channel Islands. Surprisingly, most of these changes were towards a smaller size. Black rats were introduced to Anacapa Island in the mid-1800s (probably in 1853) and eradicated in 2001-2002. To assess possible changes in these rats since their introduction, eleven cranial and four standard external measurements were taken from 59 Rattus rattus specimens collected from 1940-2000. All rat cranial traits changed 3.06-10.43% (724-2567 d, 0.06-0.42 h), and all became larger. When considered in haldanes, these changes are among the fastest on record in any organism, and far exceed changes found in other island rodents. These changes were confirmed by MANOVA (Wilk's λ < 0.0005, F d.f.15 = 2974.386, P < 0.0005), and all 11 cranial traits significantly fit linear regressions. We speculate that concurrent changes in mice may have been due in part to competition with and/or predation by rats. Future research might evaluate whether the vector of mouse evolution on Anacapa is again changing after rat eradication. PMID:25780765

  18. Modeling long-term morphological change and mixed bed sediment evolution in the Deschutes Estuary

    NASA Astrophysics Data System (ADS)

    George, D. A.; Gelfenbaum, G.; Lesser, G. R.; Stevens, A. W.

    2006-12-01

    For modeling systems in extreme disequilibrium, such as an impounded estuary or diked coastal wetland, coupling between the bed and the hydrodynamic forces from tides and rivers that can redistribute accumulated sediment is vital. The feedback among the evolving bed sediment grain size, bathymetry, sediment transport, and hydrodynamics increases in importance when the time scale extends beyond months to years or decades. The Deschutes Estuary Feasibility Study, in Olympia, Washington, which is investigating estuarine response to removing a dam, provides an opportunity to examine this coupling. A hydrodynamic and sediment transport model was constructed with the numerical model Delft3D to predict the flow, sediment transport, and morphological change under several estuary restoration scenarios. Multi-year (1, 3 and 10 year) morphological simulations required simplifying data inputs and implementing a time-scale acceleration technique. A sediment discharge climatology based on the Deschutes River hydrograph and a representative tide selected from the spring-neap tidal cycle are used to force the model. To reduce computational time, a variable morphological factor is employed, which relates the hydrodynamic and the morphologic time scales. Surface grab samples were collected to quantify the dominant bed sediment grain sizes but no other information regarding sediment erodibility was available. Four sediment sizes are used to represent the bed: clay (2 μm), silt (31 μm), sand (200 μm) and gravel (2000 μm). Sediment properties, such as critical shear stress for erosion, erosion rate, and dry density of mud fractions, are based on published observations in similar environments, and sensitivity to a range of values is tested. Long-term morphological simulations after removing the dam show that as the primary channel erodes, the sediment in the channel coarsens and sediment along the adjacent tide flats gets finer. A portion of the fine sediment that erodes from the

  19. Diabetes-induced morphological, biomechanical, and compositional changes in ocular basement membranes.

    PubMed

    To, Margaret; Goz, Alexandra; Camenzind, Leon; Oertle, Philipp; Candiello, Joseph; Sullivan, Mara; Henrich, Paul Bernhard; Loparic, Marko; Safi, Farhad; Eller, Andrew; Halfter, Willi

    2013-11-01

    The current study investigates the structural and compositional changes of ocular basement membranes (BMs) during long-term diabetes. By comparing retinal vascular BMs and the inner limiting membrane (ILM) from diabetic and non-diabetic human eyes by light and transmission electron microscopy (TEM), a massive, diabetes-related increase in the thickness of these BMs was detected. The increase in ILM thickness was confirmed by atomic force microscopy (AFM) on native ILM flat-mount preparations. AFM also detected a diabetes-induced increase in ILM stiffness. The changes in BM morphology and biophysical properties were accompanied by partial changes in the biochemical composition as shown by immunocytochemistry and western blots: agrin, fibronectin and tenascin underwent relative increases in concentration in diabetic BMs as compared to non-diabetic BMs. Fibronectin and tenascin were particularly high in the BMs of outlining microvascular aneurisms. The present data showed that retinal vascular BMs and the ILM undergo morphological, biomechanical and compositional changes during long-term diabetes. The increase in BM thickness not only resulted from an up-regulation of the standard BM proteins, but also from the expression of diabetes-specific extracellular matrix proteins that are not normally found in retinal BMs. PMID:24095823

  20. Changes of RBC aggregation in oxygenation-deoxygenation: pH dependency and cell morphology.

    PubMed

    Cicha, Iwona; Suzuki, Yoji; Tateishi, Norihiko; Maeda, Nobuji

    2003-06-01

    The effects of the oxygenation-deoxygenation process on red blood cell (RBC) aggregation were examined in relation to morphological changes in RBCs and the contribution of CO(2). A low-shear rheoscope was used to measure the rate of rouleaux (one-dimensional aggregate) formation in diluted autologous plasma exposed to gas mixtures with different Po(2) and Pco(2). RBC indexes and RBC suspension pH were measured for the oxygenated or the deoxygenated condition, and the cell shape was observed with a scanning electron microscope. In the oxygenation-deoxygenation process, the rate of rouleaux formation increased with rising pH of the RBC suspension, which was lowered in the presence of CO(2). The rate increased with increasing mean corpuscular hemoglobin concentration (thus the cells shrank), which increased with rising pH and decreased in the presence of CO(2). With rising pH, cell diameter increased and cell thickness decreased (thus the cell flattened). In addition, slight echinocytosis was induced in the presence of CO(2), and the aggregation was reduced by the morphological change. In conclusion, RBC aggregation in the oxygenation-deoxygenation process is mainly influenced by the pH-dependent change in the surface area-to-volume ratio of the cells, and the aggregation is modified by CO(2)-induced acidification and the accompanying changes in mean corpuscular hemoglobin concentration and cell shape. PMID:12742832

  1. Effects of Selenium on Morphological Changes in Candida utilis ATCC 9950 Yeast Cells.

    PubMed

    Kieliszek, Marek; Błażejak, Stanisław; Bzducha-Wróbel, Anna; Kurcz, Agnieszka

    2016-02-01

    This paper presents the results of microscopic examinations of the yeast cells cultured in yeast extract-peptone-dextrose (YPD) media supplemented with sodium selenite(IV). The analysis of the morphological changes in yeast cells aimed to determine whether the selected selenium doses and culturing time may affect this element accumulation in yeast cell structures in a form of inorganic or organic compounds, as a result of detoxification processes. The range of characteristic morphological changes in yeasts cultivated in experimental media with sodium selenite(IV) was observed, including cell shrinkage and cytoplasm thickening of the changes within vacuole structure. The processes of vacuole disintegration were observed in aging yeast cells in culturing medium, which may indicate the presence of so-called ghost cells lacking intracellular organelles The changes occurring in the morphology of yeasts cultured in media supplemented with sodium selenite were typical for stationary phase of yeast growth. From detailed microscopic observations, larger surface area of the cell (6.03 μm(2)) and yeast vacuole (2.17 μm(2)) were noticed after 24-h culturing in the medium with selenium of 20 mg Se(4+)/L. The coefficient of shape of the yeast cells cultured in media enriched with sodium selenite as well as in the control YPD medium ranged from 1.02 to 1.22. Elongation of cultivation time (up to 48 and 72 h) in the media supplemented with sodium selenite caused a reduction in the surface area of the yeast cell and vacuole due to detoxification processes. PMID:26166197

  2. Quantification of changes in zero valent iron morphology using X-ray computed tomography.

    PubMed

    Luo, Ping; Bailey, Elizabeth H; Mooney, Sacha J

    2013-11-01

    Morphological changes within the porous architecture of laboratory scale zero valent iron (ZVI) permeable reactive barriers (PRBs), after exposure to different groundwater conditions, have been quantified experimentally for different ZVI/sand ratios (10%, 50% and 100%, W/W) with the aim of inferring porosity changes in field barriers. Column studies were conducted to simulate interaction with different water chemistries, a synthetic groundwater, acidic drainage and deionised (DI) water as control. Morphological changes, in terms of pore size and distribution, were measured using X-ray computed tomography (CT). CT image analysis revealed significant morphological changes in columns treated with different water chemistries. For example, 100% ZVI (W/W) columns had a higher frequency of small pores (0.6 mm) was observed in ZVI grains reacted with typical groundwater, resulting in a porosity of 27%, compared to 32% when exposed to DI water. In comparison, ZVI grains treated with the acidic drainage had higher porosity (44%) and larger average pore size (2.8 mm). 10% ZVI PRB barrier material had the highest mean porosity (56%) after exposure to any water chemistry whilst 100% ZVI (W/W) columns always had the lowest (34%) with the 50% ZVI (W/W) in between (40%). These results agree with previously published PRB field data and simultaneously conducted geochemical monitoring and mass balance calculation, indicating that both the geochemical and hydraulic environment of the PRB play an important role in determining barrier lifespan. This study suggests that X-ray CT image analysis is a powerful tool for studying the detailed inter pores between ZVI grains within PRBs. PMID:24552065

  3. The fat and the furriest: morphological changes in harp seal fur with ontogeny.

    PubMed

    Gmuca, Natalia V; Pearson, Linnea E; Burns, Jennifer M; Liwanag, Heather E M

    2015-01-01

    Ontogenetic changes in physiological performance often exemplify the development of adaptations to environmental challenges. For mammals in polar regions, the extreme cold of the environment presents a constant challenge to thermal homeostasis. The harp seal (Pagophilus groenlandicus) is an Arctic species that shifts its thermoregulatory strategy with ontogeny. Adult harp seals primarily use blubber for insulation, but newborn harp seals instead rely on their fur coat while their blubber layer develops. Harp seal pups are weaned abruptly, less than 2 wk after birth, and must subsequently learn to swim and dive in frigid waters on their own. This study examined how the morphological characteristics of harp seal fur change with ontogeny. We compared hair length, hair circularity, and hair density for neonates (1 d old; n = 7), early-nursing pups (4 d old; n = 3), late-nursing pups (9 d old; n = 4), newly weaned (molting) pups (2 wk old; n = 5), late-weaned (molted) pups (3 wk old; n = 4), and adult harp seals (n = 4). Hairs were shorter (P < 0.001) and flatter (P < 0.001) in older animals. Additionally, hair density decreased with age (P < 0.001), in terms of both the average number of hair bundles per unit area and the average number of underhairs present in any given bundle. These morphological changes were associated with a reduced thermal resistance of the pelt in late-weaned (molted) pups and adults (P < 0.001). Results are consistent with known evolutionary patterns of fur morphology associated with the transition from fur to blubber in aquatic species, yet this is the first time such morphological differences have been demonstrated across age classes within a single species. Thus, the ontogenetic patterns described here for harp seals recapitulate the convergent phylogenetic patterns observed across secondarily aquatic species. Overall, the timing of these ontogenetic changes may limit the ability of harp seals to adapt to the deterioration of sea ice in the

  4. USE OF LIDAR TO MAP STREAM MORPHOLOGY AND MONITOR CHANGES DUE TO URBANIZATION OF A SMALL SUBURBAN WATERSHED

    EPA Science Inventory

    Urbanization has been associated with changes in stream flow regime, morphology, and water
    quality of rural watersheds being developed. Most studies of the effect of urbanization on stream morphology have been done post hoc -after development has occurred -and involve the ext...

  5. Chronic administration of resveratrol prevents morphological changes in prefrontal cortex and hippocampus of aged rats.

    PubMed

    Monserrat Hernández-Hernández, Elizabeth; Serrano-García, Carolina; Antonio Vázquez-Roque, Rubén; Díaz, Alfonso; Monroy, Elibeth; Rodríguez-Moreno, Antonio; Florán, Benjamin; Flores, Gonzalo

    2016-05-01

    Resveratrol may induce its neuroprotective effects by reducing oxidative damage and chronic inflammation apart from improving vascular function and activating longevity genes, it also has the ability to promote the activity of neurotrophic factors. Morphological changes in dendrites of the pyramidal neurons of the prefrontal cortex (PFC) and hippocampus have been reported in the brain of aging humans, or in humans with neurodegenerative diseases such as Alzheimer's disease. These changes are reflected particularly in the decrement of both the dendritic tree and spine density. Here we evaluated the effect of resveratrol on the dendrites of pyramidal neurons of the PFC (Layers 3 and 5), CA1- and CA3-dorsal hippocampus (DH) as well as CA1-ventral hippocampus, dentate gyrus (DG), and medium spiny neurons of the nucleus accumbens of aged rats. 18-month-old rats were administered resveratrol (20 mg/kg, orally) daily for 60 days. Dendritic morphology was studied by the Golgi-Cox stain procedure, followed by Sholl analysis on 20-month-old rats. In all resveratrol-treated rats, a significant increase in dendritic length and spine density in pyramidal neurons of the PFC, CA1, and CA3 of DH was observed. Interestingly, the enhancement in dendritic length was close to the soma in pyramidal neurons of the PFC, whereas in neurons of the DH and DG, the increase in dendritic length was further from the soma. Our results suggest that resveratrol induces modifications of dendritic morphology in the PFC, DH, and DG. These changes may explain the therapeutic effect of resveratrol in aging and in Alzheimer's disease. PMID:26789275

  6. Restraint Stress-Induced Morphological Changes at the Blood-Brain Barrier in Adult Rats

    PubMed Central

    Sántha, Petra; Veszelka, Szilvia; Hoyk, Zsófia; Mészáros, Mária; Walter, Fruzsina R.; Tóth, Andrea E.; Kiss, Lóránd; Kincses, András; Oláh, Zita; Seprényi, György; Rákhely, Gábor; Dér, András; Pákáski, Magdolna; Kálmán, János; Kittel, Ágnes; Deli, Mária A.

    2016-01-01

    Stress is well-known to contribute to the development of both neurological and psychiatric diseases. While the role of the blood-brain barrier is increasingly recognized in the development of neurodegenerative disorders, such as Alzheimer's disease, dysfunction of the blood-brain barrier has been linked to stress-related psychiatric diseases only recently. In the present study the effects of restraint stress with different duration (1, 3, and 21 days) were investigated on the morphology of the blood-brain barrier in male adult Wistar rats. Frontal cortex and hippocampus sections were immunostained for markers of brain endothelial cells (claudin-5, occluding, and glucose transporter-1) and astroglia (GFAP). Staining pattern and intensity were visualized by confocal microscopy and evaluated by several types of image analysis. The ultrastructure of brain capillaries was investigated by electron microscopy. Morphological changes and intensity alterations in brain endothelial tight junction proteins claudin-5 and occludin were induced by stress. Following restraint stress significant increases in the fluorescence intensity of glucose transporter-1 were detected in brain endothelial cells in the frontal cortex and hippocampus. Significant reductions in GFAP fluorescence intensity were observed in the frontal cortex in all stress groups. As observed by electron microscopy, 1-day acute stress induced morphological changes indicating damage in capillary endothelial cells in both brain regions. After 21 days of stress thicker and irregular capillary basal membranes in the hippocampus and edema in astrocytes in both regions were seen. These findings indicate that stress exerts time-dependent changes in the staining pattern of tight junction proteins occludin, claudin-5, and glucose transporter-1 at the level of brain capillaries and in the ultrastructure of brain endothelial cells and astroglial endfeet, which may contribute to neurodegenerative processes, cognitive and

  7. Morphological changes and depressed phagocytic efficiency in Dictyostelium amoebae treated with toxic concentrations of cadmium

    SciTech Connect

    Cyr, R.J.; Bernstein, R.L.

    1984-10-01

    The morphology and phagocytic efficiency of Dictyostelium discoideum amoebae exposed to cadmium was investigated at two Cd concentrations: a low toxic concentration - 7 x 10/sup -5/ m, and a high toxic concentration - 2 x 10/sup -4/ m. Both concentrations inhibited growth completely; however, only in the culture containing a high toxic concentration of cadmium were severe ultrastructural anomalies observed, notably, nucleolar changes and autophagic vacuolar formation. Using biological indices it was concluded that the high concentration of cadmium was lethal and that morphological changes associated with this dose of cadmium may be secondary to cell death. In contrast, amoebae treated with a low toxic but nonlethal concentration of Cd showed an altered size distribution of cytoplasmic vacuoles and a decreased phagocytic efficiency. Cultures whose growth was completely inhibited with cobalt were also examined, as were untreated control cultures. By 24 hr Cd-treated amoebae showed a 20% decrease in the cytoplasmic mean-vacuolar diameter and a 69% decrease in phagocytic efficiency whereas Co and untreated controls showed no significant decrease in the cytoplasmic mean-vacuolar diameter. Phagocytic efficiency was only slightly diminished by Co. Changes in vacuolar profiles had been shown earlier to be related to membrane utilization in Dictyostelium amoebae. Cd at low toxic concentrations affects membrane function in Dictyostelium amoebae.

  8. Scanning electron microscopic study of laser-induced morphologic changes of a coated enamel surface

    SciTech Connect

    Hess, J.A. )

    1990-01-01

    A low-energy Nd:YAG laser was used to irradiate extracted human teeth coated with a black energy-absorbent laser initiator in a study to determine the extent of the morphologic changes produced in the enamel surface. The laser initiator was applied to a cleaned enamel surface and irradiated at an energy output of 30 mJ or 75 mJ. Both energy levels produced morphologic changes of the surface. There was a sharp line of demarcation between the coated, irradiated area and the surrounding noncoated enamel surface. The scanning electron microscope view at the lower energy level showed that the surface had melted and reformed with numerous small, bubble-like inclusions. The 75 mJ energy level showed individual impact craters with shallow centers and raised edges containing numerous pores and large, bubble-like inclusions. Etching is a dental procedure in which an acid is normally used to remove a thin outer layer of the tooth structure. This is necessary to create a roughened, irregular surface in order to provide mechanical retention for dental restorative materials. The changes produced by the laser in this study suggest a simple, effective, and controlled method of etching the enamel surface of a tooth by altering its surface characteristics.

  9. Modeling Changing Morphology and Density Dependent Groundwater Flow in a Dynamic Environment: case study

    NASA Astrophysics Data System (ADS)

    Huizer, Sebastian; Bierkens, Marc; Oude Essink, Gualbert

    2015-04-01

    The prospect of sea level rise and increase in extreme weather conditions has led to a new focus on coastal defense in the Netherlands. As an innovative solution for coastal erosion a mega-nourishment named the Sand Motor (or Sand Engine) has been constructed at the Dutch coast. This body of sand will be distributed slowly along the coastline by wind, waves and currents; keeping the coastal defense structures in place and creating a unique, dynamic environment with changing morphology over time. The large size and position of the Sand Motor might lead to a substantial increase of fresh ground water resources. This creates an opportunity to combine coastal protection with an increase of fresh water resources in coastal regions. With a three dimensional, density dependent, groundwater model the effects of changing morphology over time and the potential increase in fresh water availability have been studied. The preliminary model calculations show that in a period of 20 years volume of fresh water gradually increases to ca. 12 Mm3. In the nearby dune area 7-8 Mm3 is abstracted yearly, therefore the first results are promising in increasing fresh groundwater resources. More model calculations will be performed to investigate the sensitivity of the change in the fresh, brackish and salt water distribution.

  10. Metabolic and morphological changes of an oil accumulating trebouxiophycean alga in nitrogen-deficient conditions.

    PubMed

    Ito, Takuro; Tanaka, Miho; Shinkawa, Haruka; Nakada, Takashi; Ano, Yoshitaka; Kurano, Norihide; Soga, Tomoyoshi; Tomita, Masaru

    2013-03-01

    Oil-rich algae have promising potential for a next-generation biofuel feedstock. Pseudochoricystis ellipsoidea MBIC 11204, a novel unicellular green algal strain, accumulates a large amount of oil (lipids) in nitrogen-deficient (-N) conditions. Although the oil bodies are easily visualized by lipophilic staining in the cells, little is known about how oil bodies are metabolically synthesized. Clarifying the metabolic profiles in -N conditions is important to understand the physiological mechanisms of lipid accumulations and will be useful to optimize culture conditions efficiently produce industrial oil. Metabolome and lipidome profiles were obtained, respectively, using capillary electrophoresis- and liquid chromatography-mass spectrometry from P. ellipsoidea in both nitrogen-rich (+N; rapid growth) and -N conditions. Relative quantities of more than 300 metabolites were systematically compared between these two conditions. Amino acids in nitrogen assimilation and N-transporting metabolisms were decreased to 1/20 the amount, or less, in -N conditions. In lipid metabolism, the quantities of neutral lipids increased greatly in -N conditions; however, quantities of nearly all the other lipids either decreased or only changed slightly. The morphological changes in +N and -N conditions were also provided by microscopy, and we discuss their relationship to the metabolic changes. This is the first approach to understand the novel algal strain's metabolism using a combination of wide-scale metabolome analysis and morphological analysis. PMID:23463323

  11. A model of transcriptional and morphological changes during thyroid hormone-induced metamorphosis of the axolotl

    PubMed Central

    Page, Robert B.; Monaghan, James R.; Walker, John A.; Voss, S. Randal

    2009-01-01

    Anuran (frog) metamorphosis has long-served as a model of how thyroid hormones regulate post-embryonic development in vertebrates. However, comparatively little is known about urodele (salamander) metamorphosis. We conducted a detailed time-course study of induced metamorphosis in the Mexican axolotl (Ambystoma mexicanum) that probed metamorphic changes in morphology and gene expression in the skin. Using morphometrics, quantitative PCR, histology, and in situ hybridization we demonstrate that the development of transcriptional markers is fundamental to the resolution of early metamorphic events in axolotls. We then use linear and piecewise linear models to identify a sequence of morphological and transcriptional changes that define larval to adult remodeling events throughout metamorphosis. In addition, we show that transcriptional biomarkers are expressed in specific larval and adult cell populations of the skin and that temporal changes in these biomarkers correlate with tissue remodeling. We compare our results with other studies of natural and induced metamorphosis in urodeles and highlight what appear to be conserved features between urodele and anuran metamorphosis. PMID:19275901

  12. Morphologic Changes in Acute Central Serous Chorioretinopathy Using Spectral Domain Optical Coherence Tomography

    PubMed Central

    Cho, Won Bin; Chung, Hyewon

    2012-01-01

    Purpose To investigate morphologic changes of acute central serous chorioretinopathy (CSC) using spectral domain optical coherence tomography (SD-OCT) and confocal scanning laser ophthalmoscopy. Methods This retrospective study included 63 eyes of 63 patients with unilateral acute CSC. All patients underwent simultaneous SD-OCT and fluorescein angiography examination using Spectralis HRA+OCT. Results The external limiting membrane could be seen on SD-OCT, although the junction between photoreceptor inner and outer segments (IS/OS) was not detected in all eyes with retinal detachment (RD). However, IS/OS became visible after resolution of serous RD in 51 eyes (81.0%). SD-OCT images at the leakage sites showed a bump of retinal pigment epithelium (RPE) in in 47 cases (68.1%) and pigment epithelial detachment (PED) in 22 of 69 leakage sites (31.9%). In 14 of 69 leakage sites (20.3%), highly reflective areas suggesting fibrinous exudate were observed in the subretinal space. In nine leakage sites (13.0%), sagging or dipping of the posterior retinal layer was seen. Abnormal RPE changes such as RPE bump and PED were observed in 12 of 22 fellow eyes (54.5%). Conclusions A variety of morphologic changes could be identified on SD-OCT, and those findings may contribute more information to our understanding of the pathophysiology of CSC. PMID:23060721

  13. 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

  14. Rapid morphological divergence of a stream fish in response to changes in water flow

    PubMed Central

    Cureton, James C.; Broughton, Richard E.

    2014-01-01

    Recent evidence indicates that evolution can occur on a contemporary time scale. However, the precise timing and patterns of phenotypic change are not well known. Reservoir construction severely alters selective regimes in aquatic habitats due to abrupt cessation of water flow. We examined the spatial and temporal patterns of evolution of a widespread North American stream fish (Pimephales vigilax) in response to stream impoundment. Gross morphological changes occurred in P. vigilax populations following dam construction in each of seven different rivers. Significant changes in body depth, head shape and fin placement were observed relative to fish populations that occupied the rivers prior to dam construction. These changes occurred over a very small number of generations and independent populations exhibited common responses to similar selective pressures. The magnitude of change was observed to be greatest in the first 15 generations post-impoundment, followed by continued but more gradual change thereafter. This pattern suggests early directional selection facilitated by phenotypic plasticity in the first 10–20 years, followed by potential stabilizing selection as populations reached a new adaptive peak (or variation became exhausted). This study provides evidence for rapid, apparently adaptive, phenotypic divergence of natural populations due to major environmental perturbations in a changing world.

  15. Leaf litter resource quality induces morphological changes in wood frog (Lithobates sylvaticus) metamorphs.

    PubMed

    Stoler, Aaron B; Stephens, Jeffrey P; Relyea, Rick A; Berven, Keith A; Tiegs, Scott D

    2015-11-01

    For organisms that exhibit complex life cycles, resource conditions experienced by individuals before metamorphosis can strongly affect phenotypes later in life. Such resource-induced effects are known to arise from variation in resource quantity, yet little is known regarding effects stemming from variation in resource quality (e.g., chemistry). For larval anurans, we hypothesized that variation in resource quality will induce a gradient of effects on metamorph morphology. We conducted an outdoor mesocosm experiment in which we manipulated resource quality by rearing larval wood frogs (Lithobates sylvaticus) under 11 leaf litter treatments. The litter species represented plant species found in open- and closed-canopy wetlands and included many plant species of current conservation concern (e.g., green ash, common reed). Consistent with our hypothesis, we found a gradient of responses for nearly all mass-adjusted morphological dimensions. Hindlimb dimensions and gut mass were positively associated with litter nutrient content and decomposition rate. In contrast, forelimb length and head width were positively associated with concentrations of phenolic acids and dissolved organic carbon. Limb lengths and widths were positively related with the duration of larval period, and we discuss possible hormonal mechanisms underlying this relationship. There were very few, broad differences in morphological traits of metamorphs between open- and closed-canopy litter species or between litter and no-litter treatments. This suggests that the effects of litter on metamorph morphology are litter species-specific, indicating that the effects of changing plant community structure in and around wetlands will largely depend on plant species composition. PMID:26188520

  16. Clonal Diversification and Changes in Lipid Traits and Colony Morphology in Mycobacterium abscessus Clinical Isolates.

    PubMed

    Park, In Kwon; Hsu, Amy P; Tettelin, Hervé; Shallom, Shamira J; Drake, Steven K; Ding, Li; Wu, Un-In; Adamo, Nick; Prevots, D Rebecca; Olivier, Kenneth N; Holland, Steven M; Sampaio, Elizabeth P; Zelazny, Adrian M

    2015-11-01

    The smooth-to-rough colony morphology shift in Mycobacterium abscessus has been implicated in loss of glycopeptidolipid (GPL), increased pathogenicity, and clinical decline in cystic fibrosis (CF) patients. However, the evolutionary phenotypic and genetic changes remain obscure. Serial isolates from nine non-CF patients with persistent M. abscessus infection were characterized by colony morphology, lipid profile via thin-layer chromatography and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), sequencing of eight genes in the GPL locus, and expression level of fadD23, a key gene involved in the biosynthesis of complex lipids. All 50 isolates were typed as M. abscessus subspecies abscessus and were clonally related within each patient. Rough isolates, all lacking GPL, predominated at later disease stages, some showing variation within rough morphology. While most (77%) rough isolates harbored detrimental mutations in mps1 and mps2, 13% displayed previously unreported mutations in mmpL4a and mmpS4, the latter yielding a putative GPL precursor. Two isolates showed no deleterious mutations in any of the eight genes sequenced. Mixed populations harboring different GPL locus mutations were detected in 5 patients, demonstrating clonal diversification, which was likely overlooked by conventional acid-fast bacillus (AFB) culture methods. Our work highlights applications of MALDI-TOF MS beyond identification, focusing on mycobacterial lipids relevant in virulence and adaptation. Later isolates displayed accumulation of triacylglycerol and reduced expression of fadD23, sometimes preceding rough colony onset. Our results indicate that clonal diversification and a shift in lipid metabolism, including the loss of GPL, occur during chronic lung infection with M. abscessus. GPL loss alone may not account for all traits associated with rough morphology. PMID:26292297

  17. Controls on sediment dynamics and medium-term morphological change in a barred microtidal beach (Cala Millor, Mallorca, Western Mediterranean)

    NASA Astrophysics Data System (ADS)

    Gómez-Pujol, Lluís; Orfila, Alejandro; Álvarez-Ellacuría, Amaya; Tintoré, Joaquín

    2011-09-01

    This paper describes the sedimentological and morphological evolution of a microtidal beach over an eight-month period under varying hydrodynamic conditions. During the monitoring a set of transverse to crescentic bars migrated onshore welded to the upper beach and then they were flattened under energetic wave conditions. The grain size distribution of surficial sediments did vary consistently across the beach profile and temporal changes in the sedimentology were mostly related to the seasonal morphological response. From our results we can state that changes in the beach morphology resulting from erosion and deposition might induce, at least to some degree, concomitant changes in the beach when hydrodynamics exceed some intensity and duration levels (Hs > 1 m). Wave climate, rather than wave forcing is the major control on sediment and morphological change co-variation.

  18. Field and video observations of morphological change under consecutive storm events (ECORS Truc Vert'08)

    NASA Astrophysics Data System (ADS)

    Senechal, Nadia; Rejas, Antoine; Coco, Giovanni; Bryan, Karin; Macmahan, Jamie; Capo, Sylvain; Parisot, Jean-Paul

    2010-05-01

    Morphological changes occurring over short and long temporal scales remain a major challenge in nearshore research. Because of the expected rise in mean sea level and storminess increase, beach response to changing wave conditions is of key interest to coastal managers. Current numerical models of beach change have limited predictive skills and the need to collect field observations to gain insight on processes determining beach response is widely acknowledged. A field experiment was performed in 2008 at Truc Vert, a macrotidal beach on the southern part of the French Atlantic coast. The experiment involved scientists from 6 countries (for a total of 16 institutions) and measurements of waves, currents, sediment transport and morphological changes were collected for a period of 6 weeks. We here focus on the analysis of morphological changes that occurred on the beachface and intertidal area during the experiment. Bed levels over an area spanning about 800 m in the alongshore direction were monitored daily using a DGPS system mounted on an ATV while the lower part of the swash zone was surveyed on foot. Video observations were collected using a 2-camera system deployed on a tower on top of the dunes and provided observations of shoreline and underwater sandbar position. During the field experiment, the beach experienced 2 major storms (offshore significant wave height above 5 m) as well as a period of time when offshore wave height was constantly around or above 3 m (average annual wave height at this site is 1.36 m) for a period of 10 days. Morphological response to storms and subsequent recovery patterns varied in both the alongshore and cross-shore direction and appear to be strongly influenced by the angle of wave approach and pre-existing morphological conditions of the beachface and the intertidal sandbar. Our analysis shows that the response of the upper intertidal part of the beach was very different between the three storms. In particular, whereas the first

  19. The Morphological and Molecular Changes of Brain Cells Exposed to Direct Current Electric Field Stimulation

    PubMed Central

    Pelletier, Simon J.; Lagacé, Marie; St-Amour, Isabelle; Arsenault, Dany; Cisbani, Giulia; Chabrat, Audrey; Fecteau, Shirley; Lévesque, Martin

    2015-01-01

    Background: The application of low-intensity direct current electric fields has been experimentally used in the clinic to treat a number of brain disorders, predominantly using transcranial direct current stimulation approaches. However, the cellular and molecular changes induced by such treatment remain largely unknown. Methods: Here, we tested various intensities of direct current electric fields (0, 25, 50, and 100V/m) in a well-controlled in vitro environment in order to investigate the responses of neurons, microglia, and astrocytes to this type of stimulation. This included morphological assessments of the cells, viability, as well as shape and fiber outgrowth relative to the orientation of the direct current electric field. We also undertook enzyme-linked immunosorbent assays and western immunoblotting to identify which molecular pathways were affected by direct current electric fields. Results: In response to direct current electric field, neurons developed an elongated cell body shape with neurite outgrowth that was associated with a significant increase in growth associated protein-43. Fetal midbrain dopaminergic explants grown in a collagen gel matrix also showed a reorientation of their neurites towards the cathode. BV2 microglial cells adopted distinct morphological changes with an increase in cyclooxygenase-2 expression, but these were dependent on whether they had already been activated with lipopolysaccharide. Finally, astrocytes displayed elongated cell bodies with cellular filopodia that were oriented perpendicularly to the direct current electric field. Conclusion: We show that cells of the central nervous system can respond to direct current electric fields both in terms of their morphological shape and molecular expression of certain proteins, and this in turn can help us to begin understand the mechanisms underlying the clinical benefits of direct current electric field. PMID:25522422

  20. Radon exposure mediated changes in lung macrophage morphology and function, in vitro

    SciTech Connect

    Seed, T.M.; Niiro, G.K.; Kretz, N.D.

    1990-01-01

    Bronchopulmonary macrophages play a key role in the normal physiology of the respiratory system. Potential respiratory dysfunctions due to radon/radon daughter exposure-mediated damage of the macrophage lung cell population has been explored via in vitro technology. In this study, macrophages were isolated from lungs of normal healthy dogs by saline lavage, cultured for varying periods (0-96 h) in the presence or absence of radon gas, and assessed for radon dose-dependent changes in cell morphology and function. The in vitro culture procedure and the cell exposing system allowed for detailed alpha particle dosimetry, in relation to the assessed biological end points; i.e. (1) exposure-dependent changes in macrophage surface topography, (2) capacity to elaborate specific growth factor (CSF) essential for self maintenance, and (3) alterations in cell viability. Highlights of the morphologic assessment indicate that relatively low alpha particle doses arising from protracted radon/radon daughter exposure elicites pronounced topographic alterations of the exposed macrophage's cell surface. 27 refs., 7 figs., 1 tab.

  1. Lensing-induced morphology changes in CMB temperature maps in modified gravity theories

    NASA Astrophysics Data System (ADS)

    Munshi, D.; Hu, B.; Matsubara, T.; Coles, P.; Heavens, A.

    2016-04-01

    Lensing of the Cosmic Microwave Background (CMB) changes the morphology of pattern of temperature fluctuations, so topological descriptors such as Minkowski Functionals can probe the gravity model responsible for the lensing. We show how the recently introduced two-to-two and three-to-one kurt-spectra (and their associated correlation functions), which depend on the power spectrum of the lensing potential, can be used to probe modified gravity theories such as f(R) theories of gravity and quintessence models. We also investigate models based on effective field theory, which include the constant-Ω model, and low-energy Hořava theories. Estimates of the cumulative signal-to-noise for detection of lensing-induced morphology changes, reaches Script O(103) for the future planned CMB polarization mission COrE+. Assuming foreground removal is possible to lmax=3000, we show that many modified gravity theories can be rejected with a high level of significance, making this technique comparable in power to galaxy weak lensing or redshift surveys. These topological estimators are also useful in distinguishing lensing from other scattering secondaries at the level of the four-point function or trispectrum. Examples include the kinetic Sunyaev-Zel'dovich (kSZ) effect which shares, with lensing, a lack of spectral distortion. We also discuss the complication of foreground contamination from unsubtracted point sources.

  2. Association of Atrial Fibrillation with Morphological and Electrophysiological Changes of the Atrial Myocardium.

    PubMed

    Matějková, Adéla; Šteiner, Ivo

    2016-01-01

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. For long time it was considered as pure functional disorder, but in recent years, there were identified atrial locations, which are involved in the initiation and maintenance of this arrhythmia. These structural changes, so called remodelation, start at electric level and later they affect contractility and morphology. In this study we attempted to find a possible relation between morphological (scarring, amyloidosis, left atrial (LA) enlargement) and electrophysiological (ECG features) changes in patients with AF. We examined grossly and histologically 100 hearts of necropsy patients - 54 with a history of AF and 46 without AF. Premortem ECGs were evaluated. The patients with AF had significantly heavier heart, larger LA, more severely scarred myocardium of the LA and atrial septum, and more severe amyloidosis in both atria. Severity of amyloidosis was higher in LAs vs. right atria (RAs). Distribution of both fibrosis and amyloidosis was irregular. The most affected area was in the LA anterior wall. Patients with a history of AF and with most severe amyloidosis have more often abnormally long P waves. Finding of long P wave may contribute to diagnosis of a hitherto undisclosed atrial fibrillation. PMID:27526304

  3. Morphological changes related to age in mesial root canals of permanent mandibular first molars.

    PubMed

    Gani, Omar A; Boiero, Claudio F; Correa, Carolina; Masin, Ivana; Machado, Ricardo; Silva, Emmanuel J N L; Vansan, Luiz Pascoal

    2014-01-01

    The aim of this study was to evaluate age-related morphological canal changes in mesial root canals of mandibular first molars of known ages. Fifty-six specimens were selected for this study and distributed into the following four age groups (n. 14): a) Group of children under 13 years, b) Group of adolescents (from 14 to 19 years), c) Group of young adults (from 20 to 39 years) and d) Group of older adults (over 40 years). The specimens were in perfect condition because after extraction they were carefully cleaned, sterilized, identified and stored in water. In order to improve the cleaning, they were placed in 1% sodium hypochlorite solution for four hours and rinsed in 10 vol. hydrogen peroxide for 8 hours. After that, a clearing technique was performed to illustrate root canal anatomy. Digitalized images of all samples were obtained by use of a stereomicroscope. Canals were noticeably simpler in older adults: they were sharply defined and narrow, sometimes too narrow. Calcification nuclei were not found and there were only a few remains of internuclear spaces. The canal system appeared cleaner, clearer and more sharply defined than in the other age groups. It may be concluded that there is a correlation between aging and morphological changes in the mesial root canals of mandibular first molars. PMID:25560687

  4. Morphological changes in human neural cells following tick-borne encephalitis virus infection.

    PubMed

    Růzek, Daniel; Vancová, Marie; Tesarová, Martina; Ahantarig, Arunee; Kopecký, Jan; Grubhoffer, Libor

    2009-07-01

    Tick-borne encephalitis (TBE) is one of the leading and most dangerous human viral neuroinfections in Europe and north-eastern Asia. The clinical manifestations include asymptomatic infections, fevers and debilitating encephalitis that might progress into chronic disease or fatal infection. To understand TBE pathology further in host nervous systems, three human neural cell lines, neuroblastoma, medulloblastoma and glioblastoma, were infected with TBE virus (TBEV). The susceptibility and virus-mediated cytopathic effect, including ultrastructural and apoptotic changes of the cells, were examined. All the neural cell lines tested were susceptible to TBEV infection. Interestingly, the neural cells produced about 100- to 10,000-fold higher virus titres than the conventional cell lines of extraneural origin, indicating the highly susceptible nature of neural cells to TBEV infection. The infection of medulloblastoma and glioblastoma cells was associated with a number of major morphological changes, including proliferation of membranes of the rough endoplasmic reticulum and extensive rearrangement of cytoskeletal structures. The TBEV-infected cells exhibited either necrotic or apoptotic morphological features. We observed ultrastructural apoptotic signs (condensation, margination and fragmentation of chromatin) and other alterations, such as vacuolation of the cytoplasm, dilatation of the endoplasmic reticulum cisternae and shrinkage of cells, accompanied by a high density of the cytoplasm. On the other hand, infected neuroblastoma cells did not exhibit proliferation of membranous structures. The virions were present in both the endoplasmic reticulum and the cytoplasm. Cells were dying preferentially by necrotic mechanisms rather than apoptosis. The neuropathological significance of these observations is discussed. PMID:19264624

  5. Changes in morphology of retinal ganglion cells with eccentricity in retinal degeneration.

    PubMed

    Anderson, E E; Greferath, U; Fletcher, E L

    2016-05-01

    Ganglion cells are the output neurons of the retina and are known to remodel during the subtle plasticity changes that occur following the death of photoreceptors in inherited retinal degeneration. We examine the influence of retinal eccentricity on anatomical remodelling and ganglion cell morphology well after photoreceptor loss. Rd1 mice that have a mutation in the β subunit of phosphodiesterase 6 were used as a model of retinal degeneration and gross remodelling events were examined by processing serial sections for immunocytochemistry. Retinal wholemounts from rd1-Thy1 and control Thy1 mice that contained a fluorescent protein labelling a subset of ganglion cells were processed for immunohistochemistry at 11 months of age. Ganglion cells were classified based on their soma size, dendritic field size and dendritic branching pattern and their dendritic fields were analysed for their length, area and quantity of branching points. Overall, more remodelling was found in the central compared with the peripheral retina. In addition, the size and complexity of A2, B1, C1 and D type ganglion cells located in the central region of the retina decreased. We propose that the changes in ganglion cell morphology are correlated with remodelling events in these regions and impact the function of retinal circuitry in the degenerated retina. PMID:26670589

  6. Endothelial Cell Morphology and Migration are Altered by Changes in Gravitational Fields

    NASA Technical Reports Server (NTRS)

    Melhado, Caroline; Sanford, Gary; Harris-Hooker, Sandra

    1997-01-01

    Endothelial cell migration is important to vascular wall regeneration following injury or stress. However, the mechanism(s) governing this response is not well understood. The microgravity environment of space may complicate the response of these cells to injury. To date, there are no reports in this area. We examined how bovine aortic (BAEC) and pulmonary (BPEC) endothelial cells respond to denudation injury under hypergravity (HGrav) and simulated microgravity (MGrav), using image analysis. In 10% FBS, the migration of confluent BAEC and BPEC into the denuded area was not affected by HGrav or MGrav. However, in low FBS (0.5%), signficantly retarded migration under MGrav, and increased migration under HGrav was found. MGrav also decreased the migration of postconfluent BPEC while HGrav showed no difference. Both MGrav and HGrav strongly decreased the migration of postconfluent BAEC. Also, both cell lines showed significant morphological changes by scanning electron microscopy. These studies indicate that endothelial cell function is affected by changes in gravity.

  7. Micro-structural Change During Nucleation: From Nucleus To Bicontinuous Morphology.

    PubMed

    Jeong, Seongmin; Jho, Yongseok; Zhou, Xin

    2015-01-01

    Although the microstructure of coexistence phase provides direct insights of the nucleation mechanism and their change is substantial in the phase transition, their study is limited due to the lack of suitable tools capturing the thermodynamically unstable transient states. We resolve this problem in computational study by introducing a generalized canonical ensemble simulation and investigate the morphological change of the nucleus during the water evaporation and condensation. We find that at very low pressure, where the transition is first order, classical nucleation theory holds approximately. A main nucleus is formed in the supersaturation near spinodal, and the overall shape of the nucleus is finite and compact. On increasing the pressure of the system, more nuclei are formed even before spinodal. They merge into a larger nuclei with a smaller free energy penalty to form ramified shapes. We suggest order parameters to describe the extent of fluctuation, and their relation to the free energy profile. PMID:26526871

  8. Micro-structural Change During Nucleation: From Nucleus To Bicontinuous Morphology

    PubMed Central

    Jeong, Seongmin; Jho, Yongseok; Zhou, Xin

    2015-01-01

    Although the microstructure of coexistence phase provides direct insights of the nucleation mechanism and their change is substantial in the phase transition, their study is limited due to the lack of suitable tools capturing the thermodynamically unstable transient states. We resolve this problem in computational study by introducing a generalized canonical ensemble simulation and investigate the morphological change of the nucleus during the water evaporation and condensation. We find that at very low pressure, where the transition is first order, classical nucleation theory holds approximately. A main nucleus is formed in the supersaturation near spinodal, and the overall shape of the nucleus is finite and compact. On increasing the pressure of the system, more nuclei are formed even before spinodal. They merge into a larger nuclei with a smaller free energy penalty to form ramified shapes. We suggest order parameters to describe the extent of fluctuation, and their relation to the free energy profile. PMID:26526871

  9. Beaver dams, sediment dynamics and morphological change, Odell Creek, southwest Montana

    NASA Astrophysics Data System (ADS)

    Levine, R.; Meyer, G. A.

    2012-12-01

    Beaver (Castor canadensis) were historically part of riverine systems across North America, and enhancement of beaver populations is increasingly considered an important remedy for stream degradation problems such as incised channels. However, how beaver affect fluvial processes and resulting morphology in different fluvial environments and on various channel types requires further attention. We examine the effects of beaver damming on Odell Creek, a relatively high-energy piedmont stream in the upper Missouri River basin of southwest Montana, where air photo and real-time observations indicate that main-channel dams typically persist for only a few years. Odell Creek has a basin area of 46 km2, a snowmelt-dominated hydrograph, and peak flows of 2-10 m3s-1. Odell Creek is broadly incised along most of its length within a late Pleistocene fluvial fan surface, with mean floodplain width between confining terraces of 240 m. Channel gradient declines downstream from 0.018 - 0.004, and mean channel width for 46 cross-sections is 8.1 m. We examined the geomorphic effects of active beaver dams and the persistence of dam-induced changes in nine study reaches representing downstream channel variability and variations in dam history. In-channel sediment characteristics and storage were investigated using pebble counts, fine sediment surveys and bed sediment mapping. Discharges exceeding bankfull during 2011 spring runoff breached three active dams within reaches surveyed in 2009 and 2010, allowing for repeat channel cross-section and sediment surveys. Channel geometry and sediment analyses were also conducted at several other active and breached dam sites. Volumes of fine (≤ 2 mm) sediment stored upstream of active beaver dams ranged from 40 - 135 m3. Observations and surveys of abandoned dam sites and dam breaches revealed that the majority of sediment stored upstream of beaver dams is quickly evacuated following a breach. However, while general aggradation from damming

  10. Ontogenetic changes in the internal and external morphology of the ilium in modern humans

    PubMed Central

    Abel, Richard; Macho, Gabriele A

    2011-01-01

    Trabecular architecture forms an important structural component of bone and, depending on the loading conditions encountered during life, is organised in a systematic, bone- and species-specific manner. However, recent studies suggested that gross trabecular arrangement (e.g. density distribution), like overall bone shape, is predetermined and/or affected by factors other than loading and perhaps less plastic than commonly assumed. To explore this issue further, the present cross-sectional ontogenetic study investigated morphological changes in external bone shape in relation to changes in trabecular bundle orientation and anisotropy. Radiographs of 73 modern human ilia were assessed using radiographic and Geometric Morphometric techniques. The study confirmed the apparently strong predetermination of trabecular bundle development, i.e. prior to external loading, although loading clearly also had an effect on overall morphology. For example, the sacro-pubic bundle, which follows the path of load transmission from the auricular surface to the acetabulum, is well defined and shows relatively high levels of anisotropy from early stages of development; the situation for the ischio-iliac strut is similar. However, while the sacro-pubic strut retains a constant relationship with the external landmarks defining the joint surfaces, the ischio-iliac bundle changes its relationship with the external landmarks and becomes aligned with the iliac tubercle only during late adolescence/early adulthood. It is tentatively proposed that the rearrangement of the ischio-iliac strut may reflect a change in locomotor pattern and/or a shift in positional behavior with increasing mass after growth of external bone dimensions has slowed/ceased. PMID:21323915

  11. Dynamic monitoring of avalanches and barchan dune morphology change at different timescales

    NASA Astrophysics Data System (ADS)

    Nield, Joanna; Wiggs, Giles; Baddock, Matthew; Hipondoka, Martin

    2016-04-01

    Aeolian dune morphology responds dynamically to changing wind conditions. The lee slope avalanche dynamics of dunes are particularly sensitive to prior morphological conditions as well as the varying intensity and duration characteristics of sand transport events. Here we use terrestrial laser scanning (TLS) to measure dune surface change over minutes, hours, a week and a year during conditions of variable approach flow resulting in considerable lee slope reworking. Several different avalanche patterns are recognised that can be related to slope characteristics, wind direction and slope reworking. We find that during oblique winds, horn reworking can reduce the lee slope angle. When the dominant, formative winds of the barchan return, the reworked lee slope, perpendicular to the prior oblique wind, takes longer to start avalanching. In the central region of the dune, avalanche frequency and the extent of lee slope reworking depends on wind speed. Under high winds from the dominant direction, there is continual erosion near the dune brink central area, due to the exceedance of a critical angle of repose, whilst under weaker winds the frequency of grainfall sedimentation and avalanches diminishes and net deposition in the brink area is more common. During the week of measurements, changes to the crest-brink area and lee slope form are considerable, based on the reworking of the slope by avalanche events, and this ultimately influences the dune migration rate. Over the course of a year, we demonstrate that the shape of the barchan stoss and lee slopes can change significantly, whilst the overall dune size and general planform is maintained. Our findings help elucidate dune mobility mechanics and pattern modifications at the wind storm event scale.

  12. Metabolic and morphologic changes in the corneal endothelium. The effects of potassium cyanide, iodoacetamide, and ouabain.

    PubMed

    Laing, R A; Chiba, K; Tsubota, K; Oak, S S

    1992-11-01

    The metabolic pathways of glycolysis and mitochondrial respiration in the corneal endothelial cell are the primary sources of the adenosine triphosphate (ATP) necessary to maintain endothelial structure and pump fluid to maintain the corneal stroma in its normally dehydrated and transparent state. The correlation between endothelial metabolism and morphology in rabbits was studied for 7 days after the application of three different agents: (1) iodoacetamide, used to inhibit ATP synthesis from both glycolysis and respiration; (2) potassium cyanide (KCN), used to inhibit ATP synthesis from respiration only; and (3) ouabain, used to inhibit fluid pumping but not ATP synthesis. After application of each of these three drugs to the corneal endothelium, changes in endothelial morphology were measured. The greatest change resulted from the use of iodoacetamide. Specular microscopic examination of the endothelium after the application of iodoacetamide showed progressive degradation of the integrity of the cellular structure; after 6 hr, there were no discernible cell borders. In those corneas treated with either KCN or ouabain, only minor changes in the endothelium were seen during the full 7 days of the investigation. Computer-assisted morphometric analysis showed an increase in the coefficient of variation of both cell area and perimeter in all cases. This increase was greater in the corneas treated with ouabain than those treated with either iodoacetamide or KCN. Redox fluorometry showed that the metabolic ratio (autofluorescence of reduced pyridine nucleotides divided by that of oxidized flavoproteins) decreased significantly in the iodoacetamide-treated corneas, increased significantly in the KCN group, and showed no significant change in the corneas in the ouabain group, all compared with a control group. The results showed that (1) when ATP produced by both glycolysis and respiration was inhibited by 0.1 mmol/l iodoacetamide, the endothelial cells could not survive

  13. Impact of vegetation on the hydrodynamics and morphological changes of the Wax Lake Delta during hurricanes

    NASA Astrophysics Data System (ADS)

    Xing, F.; Kettner, A. J.; Syvitski, J. P.; Ye, Q.; Bevington, A.; Twilley, R.; Atkinson, J. H.

    2013-12-01

    Coastal wetlands are natural barriers for storms, but have become more vulnerable especially when considering sea level rise and intensification of hurricanes due to global climate change. We use the numerical model Delft3D, which incorporates a newly developed vegetation routine to analyze the impact of natural vegetation on the morphological changes of coastal wetlands. The vegetation routine takes into account: 1) the influence of vertically oriented stems of plants as well as horizontally oriented stems (bent or broken but still attached to the belowground roots and rhizomes) on the flow turbulence as well as flow momentum, and 2) the influence of plant roots on the submerged soil strength. The model is applied to the Wax Lake Delta, a river-dominated delta that is part of the larger Mississippi River Delta system, during extreme events (hurricane Katrina and Rita (2005)). Hydrodynamic components as well as waves and salinity are included in the Delft3D model simulation. Results reveal that the submerged aboveground plant stems significantly decrease flow velocity and protect the wetland from erosion. When flow velocity exceeds a critical value, plant stems start to orient horizontally and lie on the bed, which changes the 3D vertical flow structure to free water condition (log profile), and also increases the bed roughness on the wetlands. Roots help to increase the soil strength, reducing erosion of the wetlands. However, roots can also intensify erosion if they got pulled out of the soil during storm events. Typically the whole root system of plants will be pulled out together, leading to a mat of soil that is eroded. This process has been observed for some parts of the Mississippi Delta during severe hurricanes like hurricane Katrina. Storm surges generated by hurricanes can push a large amount of saline water into the freshwater wetlands. The high salinity water increases flocculation and therefore sedimentation. Overall, plants have a complex impact on

  14. Quantifying anthropogenically driven morphologic changes on a barrier island: Fire Island National Seashore, New York

    USGS Publications Warehouse

    Kratzmann, M.G.; Hapke, C.J.

    2012-01-01

    Beach scraping, beach replenishment, and the presence of moderate development have altered the morphology of the dunebeach system at Fire Island National Seashore, located on a barrier island on the south coast of Long Island, New York. Seventeen communities are interspersed with sections of natural, nonmodified land within the park boundary. Beach width, dune elevation change, volume change, and shoreline change were calculated from light detection and ranging (LIDAR), real-time kinematic global positioning system (RTK GPS), and beach profile data sets at two ???4 km long study sites. Each site contains both modified (developed, replenished, and/or scraped) and nonmodified (natural) areas. The analysis spans 9 years, from 1998 to 2007, which encompasses both scraping and replenishment events at Fire Island. The objectives of this study were to quantify and compare morphological changes in modified and nonmodified zones, and to identify erosional areas within the study sites. Areas of increased volume and shoreline accretion were observed at both sites and at the western site are consistent with sand replenishment activities. The results indicate that from 1998 to 2007 locations backed by development and that employed beach scraping and/or replenishment as erosion control measures experienced more loss of volume, width, and dune elevation as compared with adjacent nonmodified areas. A detailed analysis of one specific modification, beach scraping, shows distinct morphological differences in scraped areas relative to nonscraped areas of the beach. In general, scraped areas where there is development on the dunes showed decreases in all measured parameters and are more likely to experience overwash during storm events. Furthermore, the rapid mobilization of material from the anthropogenic (scraped) dune results in increased beach accretion downcoast. National park lands are immediately adjacent to developed areas on Fire Island, and even relatively small human

  15. Remarked morphological change in a large tidal inlet with low sediment-supply

    NASA Astrophysics Data System (ADS)

    Wang, Ya Ping; Gao, Shu; Jia, Jianjun; Liu, Yunling; Gao, Jianhua

    2014-11-01

    Sediment transport within small tidal inlets is sensitive to natural processes, whilst large tidal inlets are relatively robust systems because of their large tidal prism. However, remarked morphological changes may be initiated even under the condition of low sediment supply, as illustrated by Jiaozhou Bay, a large coastal embayment on the Shandong Peninsula, eastern China. Jiaozhou Bay is characterized by its relatively slow rate of natural change, and while the embayment has a flood-dominated entrance channel and muddy seabed, the suspended sediment concentration is generally low due to the lack of abundant source material. Observations of sediment dynamics show that net suspended sediment transport is directed towards outside of the bay, with an order of magnitude of 103 t during a tidal cycle. The export of sediment associated with this flood-dominated environment implies that the net transport pattern is controlled by tidal exchange processes rather than the strength of the seabed shear stress. Sediment budget calculations show that supply of artificial sediment into the bay can account for up to 72% of the total input, which is in agreement with the 210Pb and 137Cs radioisotope geochronologies, and this leads to accumulation rates of 100-101 mm yr-1; without this, the deposition rate would be low under natural conditions. The flood tidal delta area is also influenced by the input of anthropogenic material, and acts as a depocenter with relatively high accumulation rates. Furthermore, although the inlet system has not yet reached its equilibrium state (i.e., the entrance cross-sectional area is still larger than the equilibrium cross-sectional area), land reclamation activities have resulted in a rapid reduction of the embayment area (by 37%) over the last 80 years. Our findings indicate that the rapid changes observed in the tidal basin area and seabed morphology are mainly the result of human activity rather than natural processes.

  16. Postnatal changes in the distribution and morphology of rat substantia nigra dopaminergic neurons.

    PubMed

    Tepper, J M; Damlama, M; Trent, F

    1994-05-01

    Significant changes in the neurophysiology and neuropharmacology of nigral dopaminergic neurons take place in the first postnatal month. In order to correlate these changes with the postnatal development of dopaminergic neuron morphology and substantia nigra cytoarchitecture, brains from Sprague-Dawley rat pups of age postnatal days 1, 7, 14, 21 and 28 and adult rats were sectioned and processed for tyrosine hydroxylase immunocytochemistry. At postnatal day 1, pars compacta and pars reticulata were not clearly delineated; tyrosine hydroxylase positive neurons and a dense plexus of fibers were scattered throughout the substantia nigra. By day 7 the density of tyrosine hydroxylase positive neurons decreased markedly in ventral substantia nigra, and a dopaminergic pars compacta and a non-dopaminergic pars reticulata could be more clearly distinguished. By day 14 the substantia nigra appeared essentially as it does in the adult. Cell counts during development revealed that the number of tyrosine hydroxylase positive neurons/section in both pars compacta and pars reticulata decreased significantly from postnatal day 1 to postnatal day 14, while those in pars lateralis did not change. Tyrosine hydroxylase-positive somatic size increased modestly but significantly from postnatal day 1 to day 14 as did the diameter of the proximal and distal dendrites. However, even at day 1, the morphology of tyrosine hydroxylase positive neurons appeared essentially the same as in adults. Dendritic arborizations were well developed. The dendrites were non-varicose and modestly branched, with some of the longer ventrally directed dendrites passing through pars reticulata into the crus cerebri.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7915412

  17. Diagnostic index of 3D osteoarthritic changes in TMJ condylar morphology

    NASA Astrophysics Data System (ADS)

    Gomes, Liliane R.; Gomes, Marcelo; Jung, Bryan; Paniagua, Beatriz; Ruellas, Antonio C.; Gonçalves, João. Roberto; Styner, Martin A.; Wolford, Larry; Cevidanes, Lucia

    2015-03-01

    The aim of this study was to investigate imaging statistical approaches for classifying 3D osteoarthritic morphological variations among 169 Temporomandibular Joint (TMJ) condyles. Cone beam Computed Tomography (CBCT) scans were acquired from 69 patients with long-term TMJ Osteoarthritis (OA) (39.1 ± 15.7 years), 15 patients at initial diagnosis of OA (44.9 ± 14.8 years) and 7 healthy controls (43 ± 12.4 years). 3D surface models of the condyles were constructed and Shape Correspondence was used to establish correspondent points on each model. The statistical framework included a multivariate analysis of covariance (MANCOVA) and Direction-Projection- Permutation (DiProPerm) for testing statistical significance of the differences between healthy control and the OA group determined by clinical and radiographic diagnoses. Unsupervised classification using hierarchical agglomerative clustering (HAC) was then conducted. Condylar morphology in OA and healthy subjects varied widely. Compared with healthy controls, OA average condyle was statistically significantly smaller in all dimensions except its anterior surface. Significant flattening of the lateral pole was noticed at initial diagnosis (p < 0.05). It was observed areas of 3.88 mm bone resorption at the superior surface and 3.10 mm bone apposition at the anterior aspect of the long-term OA average model. 1000 permutation statistics of DiProPerm supported a significant difference between the healthy control group and OA group (t = 6.7, empirical p-value = 0.001). Clinically meaningful unsupervised classification of TMJ condylar morphology determined a preliminary diagnostic index of 3D osteoarthritic changes, which may be the first step towards a more targeted diagnosis of this condition.

  18. Ethanol interferes with thrombin mediated changes in the morphology and cytoskeleton of human vascular endothelial cells

    SciTech Connect

    Pratt, K.J.; Rubin, R.; Hoek, J.; Williams, S.K. )

    1991-03-15

    The effect of physiological concentrations of ethanol (EtOH) on the response of human vascular endothelial cells (EC) to thrombin was examined Treatment of EC with EtOH concentrations of 20-85mM for 2-10 min. produced no significant changes in the morphology of 3- and 4-day monolayers established on fibronectin coated polystyrene. When examined immunofluorescently no significantly changes in the microfilament or microtubule structures were seen. Exposure of EC monolayers to 0.5 and 1 U/ml of thrombin for 1-60 minutes causes a concentration and time dependent monolayer retraction, evidenced by a general decrease in cell size, increase in visible gaps in the monolayer and redistribution of the microtubule and microfilament networks. Pretreatment of EC monolayers with EtOH for 3-5 minutes prior to addition of thrombin prevents the changes seen with thrombin alone. Immunofluorescent examination of the microfilament and microtubule structures suggests than EtOH may act in part via the microtubule network, which appears to be disorganized/disrupted when the EC are exposed to EtOH and then thrombin. Colchicine studies show that EC which have been pretreated with EtOH respond to colchicine differently then cells which have not previously seen EtOH. These data suggest that EtOH may alter EC monolayer responsiveness either by indirect changes which are reflected in cytoskeletal disorganization or possibly by direct influence on the cytoskeleton.

  19. Morphological response of songbirds to 100 years of landscape change in North America.

    PubMed

    Desrochers, A

    2010-06-01

    Major landscape changes caused by humans may create strong selection pressures and induce rapid evolution in natural populations. In the last 100 years, eastern North America has experienced extensive clear-cutting in boreal areas, while afforestation has occurred in most temperate areas. Based on museum specimens, I show that wings of several boreal forest songbirds and temperate songbirds of non-forest habitats have become more pointed over the last 100 years. In contrast, wings of most temperate forest and early-successional boreal forests species have become less pointed over the same period. In contrast to wing shape, the bill length of most species did not change significantly through time. These results are consistent with the "habitat isolation hypothesis", i.e., songbirds evolved in response to recent changes in the amount of available habitat and associated implications for mobility. Rapid morphological evolution may mitigate, without necessarily preventing, negative consequences of habitat loss caused by humans through direct exploitation or climate change. PMID:20583699

  20. Nanomechanical morphology of amorphous, transition, and crystalline domains in phase change memory thin films

    NASA Astrophysics Data System (ADS)

    Bosse, J. L.; Grishin, I.; Huey, B. D.; Kolosov, O. V.

    2014-09-01

    In the search for phase change materials (PCM) that may rival traditional random access memory, a complete understanding of the amorphous to crystalline phase transition is required. For the well-known Ge2Sb2Te5 (GST) and GeTe (GT) chalcogenides, which display nucleation and growth dominated crystallization kinetics, respectively, this work explores the nanomechanical morphology of amorphous and crystalline phases in 50 nm thin films. Subjecting these PCM specimens to a lateral thermal gradient spanning the crystallization temperature allows for a detailed morphological investigation. Surface and depth-dependent analyses of the resulting amorphous, transition and crystalline regions are achieved with shallow angle cross-sections, uniquely implemented with beam exit Ar ion polishing. To resolve the distinct phases, ultrasonic force microscopy (UFM) with simultaneous topography is implemented revealing a relative stiffness contrast between the amorphous and crystalline phases of 14% for the free film surface and 20% for the cross-sectioned surface. Nucleation is observed to occur preferentially at the PCM-substrate and free film interface for both GST and GT, while fine subsurface structures are found to be sputtering direction dependent. Combining surface and cross-section nanomechanical mapping in this manner allows 3D analysis of microstructure and defects with nanoscale lateral and depth resolution, applicable to a wide range of materials characterization studies where the detection of subtle variations in elastic modulus or stiffness are required.

  1. Morphological changes of Ganoderma boninense mycelia after challenged by Trichoderma and Bacillus

    SciTech Connect

    Alexander, Arnnyitte; Chong, Khim-Phin; Dayou, Jedol

    2015-07-22

    Ganoderma boninense is a fungal pathogen that causes Basal Stem Rot (BSR) disease in oil palm. This deadly disease has caused major losses in the oil palm industry and no remedy is reported to date. The more promising control on G. boninense is the use of biological control agents (BCAs). Despite many attempts in using BCAs as a control agent but evidence on the colonization of BCAs and morphological changes of the pathogen is not well documented. We have investigated the effect of antagonist activity on the combination of Trichoderma spp. and Bacillus spp. on the morphology of G. boninense. The antagonist activity was evaluated using agar well diffusion assay. BCAs suppressed the mycelia growth of G. boninense up to 70%. Observation under Scanning Electron Microscopy (SEM) shows these BCAs induced stripping of G. boninense hyphal structure by destroying the cellular structure. Highly disrupted, disaggerated, shrivelled and lysis of G. boninense hyphal were also observed. The antifungal activity of Trichoderma spp. and Bacillus spp. observed could be associated with the production of Cell Wall Degrading Enzymes (CWDE)

  2. Levonorgestrel decreases cilia beat frequency of human fallopian tubes and rat oviducts without changing morphological structure.

    PubMed

    Zhao, Weihong; Zhu, Qian; Yan, Mingxing; Li, Cheng; Yuan, Jiangjing; Qin, Guojuan; Zhang, Jian

    2015-02-01

    Levonorgestrel, a derivative of progesterone, effectively protects women against unwanted pregnancy as an emergency contraceptive. Previous studies have not been successful in determining the mechanism by which levonorgestrel acts. In the present study we analysed cilia beat action and cilia morphology following levonorgestrel exposure in vitro and in vivo using both light and electron microscopy. There was a significant decrease in the ciliary beat frequency (CBF) of human fallopian tubes between mucosal explants bathed in 5 μmol/L levonorgestrel and those bathed in medium alone (P < 0.05). There was a tendency for CBF to decrease more in the ampulla than in isthmus, but there were no differences between the proliferative and secretory phases. In rat oviducts, levonorgestrel produced a similar reduction in CBF (~ 10%) compared with the saline control group (P < 0.05). Histological and ultrastructural analysis demonstrated no changes in the percentage of ciliated cells or in the classic '9 + 2' structure of cilia following levonorgestrel treatment in either system. Thus, levonorgestrel reduces CBF without damaging cilia morphology. Decreases in CBF may indicate a pathological role for levonorgestrel in the transportation of the ovum and zygote in the fallopian tube. PMID:25399777

  3. Diamagnetic levitation causes changes in the morphology, cytoskeleton, and focal adhesion proteins expression in osteocytes.

    PubMed

    Qian, A R; Wang, L; Gao, X; Zhang, W; Hu, L F; Han, J; Li, J B; Di, S M; Shang, Peng

    2012-01-01

    Diamagnetic levitation technology is a novel simulated weightless technique and has recently been applied in life-science research. We have developed a superconducting magnet platform with large gradient high magnetic field (LG-HMF), which can provide three apparent gravity levels, namely, μg (diamagnetic levitation), 1g, and 2g for diamagnetic materials. In this study, the effects of LG-HMF on the activity, morphology, and cytoskeleton (actin filament, microtubules, and vimentin intermediate filaments) in osteocyte - like cell line MLO-Y4 were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) methods, hematoxylin-eosin (HE) staining, and laser scanning confocal microscopy (LSCM), respectively. The changes induced by LG-HMF in distribution and expression of focal adhesion (FA) proteins, including vinculin, paxillin, and talin in MLO-Y4 were determined by LSCM and Western blotting. The results showed that LG-HMF produced by superconducting magnet had no lethal effects on MLO-Y4. Compared to control, diamagnetic levitation (μg) affected MLO-Y4 morphology, nucleus size, cytoskeleton architecture, and FA proteins distribution and expression. The study indicates that osteocytes are sensitive to altered gravity and FA proteins (vinculin, paxillin, and talin) may be involved in osteocyte mechanosensation. The diamagnetic levitation may be a novel ground-based space-gravity simulator and can be used for biological experiment at cellular level. PMID:21216704

  4. Diagnostic index of three-dimensional osteoarthritic changes in temporomandibular joint condylar morphology.

    PubMed

    Gomes, Liliane R; Gomes, Marcelo; Jung, Bryan; Paniagua, Beatriz; Ruellas, Antonio C; Gonçalves, João Roberto; Styner, Martin A; Wolford, Larry; Cevidanes, Lucia

    2015-07-01

    This study aimed to investigate imaging statistical approaches for classifying three-dimensional (3-D) osteoarthritic morphological variations among 169 temporomandibular joint (TMJ) condyles. Cone-beam computed tomography scans were acquired from 69 subjects with long-term TMJ osteoarthritis (OA), 15 subjects at initial diagnosis of OA, and 7 healthy controls. Three-dimensional surface models of the condyles were constructed and SPHARM-PDM established correspondent points on each model. Multivariate analysis of covariance and direction-projection-permutation (DiProPerm) were used for testing statistical significance of the differences between the groups determined by clinical and radiographic diagnoses. Unsupervised classification using hierarchical agglomerative clustering was then conducted. Compared with healthy controls, OA average condyle was significantly smaller in all dimensions except its anterior surface. Significant flattening of the lateral pole was noticed at initial diagnosis. We observed areas of 3.88-mm bone resorption at the superior surface and 3.10-mm bone apposition at the anterior aspect of the long-term OA average model. DiProPerm supported a significant difference between the healthy control and OA group ([Formula: see text]). Clinically meaningful unsupervised classification of TMJ condylar morphology determined a preliminary diagnostic index of 3-D osteoarthritic changes, which may be the first step towards a more targeted diagnosis of this condition. PMID:26158119

  5. Redox Imbalance and Morphological Changes in Skin Fibroblasts in Typical Rett Syndrome

    PubMed Central

    Amabile, Sonia; Belmonte, Giuseppe; Valacchi, Giuseppe; Galano, Jean-Marie; Ciccoli, Lucia; Renieri, Alessandra; Hayek, Joussef

    2014-01-01

    Evidence of oxidative stress has been reported in the blood of patients with Rett syndrome (RTT), a neurodevelopmental disorder mainly caused by mutations in the gene encoding the Methyl-CpG-binding protein 2. Little is known regarding the redox status in RTT cellular systems and its relationship with the morphological phenotype. In RTT patients (n = 16) we investigated four different oxidative stress markers, F2-Isoprostanes (F2-IsoPs), F4-Neuroprostanes (F4-NeuroPs), nonprotein bound iron (NPBI), and (4-HNE PAs), and glutathione in one of the most accessible cells, that is, skin fibroblasts, and searched for possible changes in cellular/intracellular structure and qualitative modifications of synthesized collagen. Significantly increased F4-NeuroPs (12-folds), F2-IsoPs (7.5-folds) NPBI (2.3-folds), 4-HNE PAs (1.48-folds), and GSSG (1.44-folds) were detected, with significantly decreased GSH (−43.6%) and GSH/GSSG ratio (−3.05 folds). A marked dilation of the rough endoplasmic reticulum cisternae, associated with several cytoplasmic multilamellar bodies, was detectable in RTT fibroblasts. Colocalization of collagen I and collagen III, as well as the percentage of type I collagen as derived by semiquantitative immunofluorescence staining analyses, appears to be significantly reduced in RTT cells. Our findings indicate the presence of a redox imbalance and previously unrecognized morphological skin fibroblast abnormalities in RTT patients. PMID:24987493

  6. Morphologic and phenotypic changes of human neuroblastoma cells in culture induced by cytosine arabinoside

    SciTech Connect

    Ponzoni, M.; Lanciotti, M.; Melodia, A.; Casalaro, A.; Cornaglia-Ferraris, P. )

    1989-03-01

    The effects of cytosine-arabinoside (ARA-C) on the growth and phenotypic expression of a new human neuroblastoma (NB) cell line (GI-ME-N) have been extensively tested. Low doses of ARA-C allowing more than 90% cell viability induce morphological differentiation and growth inhibition. Differentiated cells were larger and flattened with elongated dendritic processes; such cells appeared within 48 hours after a dose of ARA-C as low as 0.1 {mu}g/ml. The new morphological aspect reached the maximum expression after 5-6 days of culture being independent from the addition of extra drug to the culture. A decrease in ({sup 3}H)thymidine incorporation was also observed within 24 hours and the cell growth was completely inhibited on the sixth day. Moreover, ARA-C strongly inhibited anchorage-independent growth in soft agar assay. Membrane immunofluorescence showed several dramatic changes in NB-specific antigen expression after 5 days of treatment with ARA-C. At the same time ARA-C also modulated cytoskeletal proteins and slightly increased catecholamine expression. These findings suggest that noncytotoxic doses of ARA-C do promote the differentiation of GI-ME-N neuroblastoma cells associated with reduced expression of the malignant phenotype.

  7. Endothelial cells undergo morphological, biomechanical, and dynamic changes in response to tumor necrosis factor-α.

    PubMed

    Stroka, Kimberly M; Vaitkus, Janina A; Aranda-Espinoza, Helim

    2012-11-01

    The immune response triggers a complicated sequence of events, one of which is release of the cytokine tumor necrosis factor-α (TNF-α) from stromal cells, for example monocytes and macrophages. In this work we investigated the biophysical effects of TNF-α on endothelial cells (ECs), including changes in cell morphology, biomechanics, migration, and cytoskeletal dynamics. We found that TNF-α induces a wide distribution of cell area and aspect ratio, with these properties increasing on average during treatment. Interestingly, aspect ratio peaks after approximately 10 h of exposure to TNF-α, corresponding also to a peak in exerted traction forces. Meanwhile, ECs treated with TNF-α soften, and we associate this with significant increases in estimated cellular volume. In addition, our evaluation of migratory dynamics revealed an inverse correlation between cell aspect ratio and migration speed after TNF-α treatment, suggesting that cell shape may be an important functional regulator of EC migration during an inflammatory response. Finally, we addressed the basic mechanics of how the reorganization of F-actin filaments occurs during TNF-α treatment, and observed a dynamic shift of existing actin filaments. Together, our results suggest a functional link between EC morphology, biomechanics, migration, and cytoskeletal dynamics during an inflammatory response. PMID:22940754

  8. Endothelial cells undergo morphological, biomechanical, and dynamic changes in response to tumor necrosis factor-α

    PubMed Central

    Stroka, Kimberly M.; Vaitkus, Janina A.; Aranda-Espinoza, Helim

    2012-01-01

    The immune response triggers a complicated sequence of events, one of which is release of the cytokine tumor necrosis factor-α (TNF-α) from stromal cells such as monocytes and macrophages. In this work we explored the biophysical effects of TNF-α on endothelial cells (ECs), including changes in cell morphology, biomechanics, migration, and cytoskeletal dynamics. We found that TNF-α induces a wide distribution of cell area and aspect ratio, with these properties increasing on average during treatment. Interestingly, aspect ratio peaks around 10 hours of exposure to TNF-α, corresponding also to a peak in exerted traction forces. Meanwhile, ECs treated with TNF-α soften, and we associate this with significant increases in estimated cellular volume. In addition, our evaluation of migratory dynamics demonstrates an inverse correlation between cell aspect ratio and migration speed after TNF-α treatment, suggesting that cell shape may be an important functional regulator of EC migration during an inflammatory response. Finally, we address the basic mechanics of how the reorganization of F-actin filaments occurs during TNF-α treatment, and we demonstrate a dynamic shift of existing actin filaments. Together, our results suggest a functional link between EC morphology, biomechanics, migration, and cytoskeletal dynamics during an inflammatory response. PMID:22940754

  9. Morphological and cellular changes within embryonic striatal grafts associated with enriched environment and involuntary exercise.

    PubMed

    Döbrössy, Máté D; Dunnett, Stephen B

    2006-12-01

    Environmental enrichment (EE) and exercise have been implicated in influencing behaviour and altering neuronal processes associated with cellular morphology in both 'normal' and injured states of the CNS. Using a rodent model of Huntington's disease, we investigated whether prolonged EE or involuntary exercise can induce morphological and cellular changes within embryonic striatal transplants. Adult rats were trained on the Staircase test--requiring fine motor control to reach and collect reward pellets--prior to being lesioned unilaterally in the dorsal neostriatum with quinolinic acid. The lesioned animals received E15 whole ganglionic eminence cell suspension grafts followed by housing in EE or standard cages. Half of the animals in standard cages received daily forced exercise on a treadmill. The grafted animals showed significant functional recovery on both the Staircase test and in drug-induced rotation. Neither the housing conditions nor the training had an impact on the behaviour, with the exception of the treadmill reducing the ipsilateral drug-induced rotation observed amongst the lesioned animals. However, the animals housed in the EE had significantly increased striatal brain-derived neurotrophic factor (BDNF) levels, and graft neurons in these animals exhibited both greater spine densities and larger cell volumes. Animals on forced exercise regime had reduced BDNF levels and grafted cells with sparser spines. The study suggests that the context of the animal can affect the plasticity of transplanted cells. Appropriately exploiting the underlying, and yet unknown, mechanisms could lead the way to improved anatomical and potentially functional integration of the graft. PMID:17156383

  10. Morphological changes of Ganoderma boninense mycelia after challenged by Trichoderma and Bacillus

    NASA Astrophysics Data System (ADS)

    Alexander, Arnnyitte; Dayou, Jedol; Chong, Khim-Phin

    2015-07-01

    Ganoderma boninense is a fungal pathogen that causes Basal Stem Rot (BSR) disease in oil palm. This deadly disease has caused major losses in the oil palm industry and no remedy is reported to date. The more promising control on G. boninense is the use of biological control agents (BCAs). Despite many attempts in using BCAs as a control agent but evidence on the colonization of BCAs and morphological changes of the pathogen is not well documented. We have investigated the effect of antagonist activity on the combination of Trichoderma spp. and Bacillus spp. on the morphology of G. boninense. The antagonist activity was evaluated using agar well diffusion assay. BCAs suppressed the mycelia growth of G. boninense up to 70%. Observation under Scanning Electron Microscopy (SEM) shows these BCAs induced stripping of G. boninense hyphal structure by destroying the cellular structure. Highly disrupted, disaggerated, shrivelled and lysis of G. boninense hyphal were also observed. The antifungal activity of Trichoderma spp. and Bacillus spp. observed could be associated with the production of Cell Wall Degrading Enzymes (CWDE).

  11. Density changes of iron during morphological healing evolution of internal fatigue microcracks

    NASA Astrophysics Data System (ADS)

    Zhang, H. L.; Sun, J.; Gao, L.

    2003-12-01

    Plastic-strain-controlled fatigue was performed on pure iron specimens with uniaxial symmetric tension-compression loadings at room temperature. The as-fatigued specimens were then annealed in vacuum at 1173 K from 1 to 7 hours. The morphologies of internal fatigue microcracks were observed by scanning electron microscopy (SEM) in the as-fatigued and as-annealed specimens. The density of the specimens was measured with an electronic analytical balance. The density of the as-fatigued specimens decreased continuously as the fractional fatigue life increased, and was nearly constant when the specimens were annealed up to 2 hours at 1173 K, but increased gradually after 2 hours of annealing time. The density of some specimens eventually approximates to the value of ρ 0, the initial density, at 7 hours of annealing time. This suggests that the initial decrease in density is due to crack initiation and propagation in the as-fatigued specimens. At the early stage of annealing, the specimen density is nearly constant because the crack morphological change is controlled by surface diffusion. At the later stages, the density increases and finally returns to the initial density because the spherical voids evolved from the parent crack are reduced by volume diffusion coupled with grain-boundary diffusion. A combined model is presented to predict the shrinkage of the spherical voids within the specimens, and is in broad agreement with the experimental data.

  12. Diagnostic index of three-dimensional osteoarthritic changes in temporomandibular joint condylar morphology

    PubMed Central

    Gomes, Liliane R.; Gomes, Marcelo; Jung, Bryan; Paniagua, Beatriz; Ruellas, Antonio C.; Gonçalves, João Roberto; Styner, Martin A.; Wolford, Larry; Cevidanes, Lucia

    2015-01-01

    Abstract. This study aimed to investigate imaging statistical approaches for classifying three-dimensional (3-D) osteoarthritic morphological variations among 169 temporomandibular joint (TMJ) condyles. Cone-beam computed tomography scans were acquired from 69 subjects with long-term TMJ osteoarthritis (OA), 15 subjects at initial diagnosis of OA, and 7 healthy controls. Three-dimensional surface models of the condyles were constructed and SPHARM-PDM established correspondent points on each model. Multivariate analysis of covariance and direction-projection-permutation (DiProPerm) were used for testing statistical significance of the differences between the groups determined by clinical and radiographic diagnoses. Unsupervised classification using hierarchical agglomerative clustering was then conducted. Compared with healthy controls, OA average condyle was significantly smaller in all dimensions except its anterior surface. Significant flattening of the lateral pole was noticed at initial diagnosis. We observed areas of 3.88-mm bone resorption at the superior surface and 3.10-mm bone apposition at the anterior aspect of the long-term OA average model. DiProPerm supported a significant difference between the healthy control and OA group (p-value=0.001). Clinically meaningful unsupervised classification of TMJ condylar morphology determined a preliminary diagnostic index of 3-D osteoarthritic changes, which may be the first step towards a more targeted diagnosis of this condition. PMID:26158119

  13. Modeling Character Change Heterogeneity in Phylogenetic Analyses of Morphology through the Use of Priors.

    PubMed

    Wright, April M; Lloyd, Graeme T; Hillis, David M

    2016-07-01

    The Mk model was developed for estimating phylogenetic trees from discrete morphological data, whether for living or fossil taxa. Like any model, the Mk model makes a number of assumptions. One assumption is that transitions between character states are symmetric (i.e., the probability of changing from 0 to 1 is the same as 1 to 0). However, some characters in a data matrix may not satisfy this assumption. Here, we test methods for relaxing this assumption in a Bayesian context. Using empirical data sets, we perform model fitting to illustrate cases in which modeling asymmetric transition rates among characters is preferable to the standard Mk model. We use simulated data sets to demonstrate that choosing the best-fit model of transition-state symmetry can improve model fit and phylogenetic estimation. PMID:26715586

  14. Age-dependent changes in cat masseter nerve: an electrophysiological and morphological study.

    PubMed

    Chase, M H; Engelhardt, J K; Adinolfi, A M; Chirwa, S S

    1992-07-24

    The present study was undertaken to determine the manner in which aging affects the function and structure of the masseter nerve in old cats. Electrophysiological data demonstrated a significant decrease in the conduction velocity of the action potential in old cats compared with that observed in adult cats. Light microscopic analyses revealed an age-dependent decrease in axon diameter. Electron microscopic observations of the masseter nerve in the aged cats revealed a disruption of the myelin sheaths and a pronounced increase in collagen fibers in the endoneurium and perineurium. These morphological changes are discussed and then related to the decrease in conduction velocity which was observed in the electrophysiological portion of this study. PMID:1521161

  15. Visualizing morphological changes of clear corneal cataract incisions with optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Rao, Bin; Zhang, Jun; Taban, Mehran; McDonnell, Peter J.; Chen, Zhongping

    2004-07-01

    Dynamic morphological changes of clear corneal cataract incisions are studied with Optical Coherence Tomography (OCT). Two opposite types of dynamic incision wound behaviors are documented. A stable incision angle range is found to be existent for single-planed, clear corneal cataract incisions. When well pressurized, incision angles within this stable range result in well-apposed incision edges that resist gapping while incision angles falling outside this range have a larger tendency for wound leakage. It is also shown that a two-planed incision can effectively expand the stable range. For incision angles outside the stable range, the farther the incision angle is away from stable range, the larger the gap between incision wound edges when well pressurized. Thus, incision construction method has a major impact on the self-sealing capability of the incision wounds. In this investigation, OCT has been demonstrated as an effective modality for imaging and monitoring corneal surgery.

  16. Visible-Light-Induced Morphological Changes of Giant Vesicles by Photoisomerization of a Ruthenium Aqua Complex.

    PubMed

    Hirahara, Masanari; Tsukamoto, Akira; Goto, Hiroki; Tada, Shigeru; Yagi, Masayuki; Umemura, Yasushi

    2016-02-18

    Visible- and red-light responsive vesicles were prepared by incorporating a ruthenium aqua complex having two alkyl chains on tridentate and asymmetrical bidentate ligands (proximal-2: [Ru(C10 tpy)(C10 pyqu)OH2 ](2+) , C10 tpy=4'-decyloxy-2,2';6',2"-terpyridine, C10 pyqu=2-[2'-(6'-decyloxy)-pyridyl]quinoline). The ruthenium complex of proximal-2 with closed alkyl chain geometry and a cylinder-like molecular shape exhibited photoisomerization to distal-2 with an open alkyl chain geometry and a cone-like shape, both in an aqueous solution and in vesicle dispersions. We observed that light irradiation of giant vesicles containing proximal-2 induced diverse morphological changes. PMID:26711139

  17. Automated segmentation algorithm for detection of changes in vaginal epithelial morphology using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Chitchian, Shahab; Vincent, Kathleen L.; Vargas, Gracie; Motamedi, Massoud

    2012-11-01

    We have explored the use of optical coherence tomography (OCT) as a noninvasive tool for assessing the toxicity of topical microbicides, products used to prevent HIV, by monitoring the integrity of the vaginal epithelium. A novel feature-based segmentation algorithm using a nearest-neighbor classifier was developed to monitor changes in the morphology of vaginal epithelium. The two-step automated algorithm yielded OCT images with a clearly defined epithelial layer, enabling differentiation of normal and damaged tissue. The algorithm was robust in that it was able to discriminate the epithelial layer from underlying stroma as well as residual microbicide product on the surface. This segmentation technique for OCT images has the potential to be readily adaptable to the clinical setting for noninvasively defining the boundaries of the epithelium, enabling quantifiable assessment of microbicide-induced damage in vaginal tissue.

  18. Estimating heart shift and morphological changes during minimally invasive cardiac interventions

    NASA Astrophysics Data System (ADS)

    Linte, Cristian A.; Carias, Mathew; Cho, Daniel S.; Pace, Danielle F.; Moore, John; Wedlake, Chris; Bainbridge, Daniel; Kiaii, Bob; Peters, Terry M.

    2010-02-01

    Image-guided interventions rely on the common assumption that pre-operative information can depict intraoperative morphology with sufficient accuracy. Nevertheless, in the context of minimally invasive cardiac therapy delivery, this assumption loses ground; the heart is a soft-tissue organ prone to changes induced during access to the heart and especially intracardiac targets. In addition to its clinical value for cardiac interventional guidance and assistance with the image- and model-to-patient registration, here we show how ultrasound imaging may be used to estimate changes in the heart position and morphology of structures of interest at different stages in the procedure. Using a magnetically tracked 2D transesophageal echocardiography transducer, we acquired in vivo images of the heart at different stages during the procedural workflow of common minimally invasive cardiac procedures, including robot-assisted coronary artery bypass grafting, mitral valve replacement/repair, or modelenhanced US-guided intracardiac interventions, all in the coordinate system of the tracking system. Anatomical features of interest (mitral and aortic valves) used to register the pre-operative anatomical models to the intraoperative coordinate frame were identified from each dataset. This information allowed us to identify the global position of the heart and also characterize the valvular structures at various peri-operative stages, in terms of their orientation, size, and geometry. Based on these results, we can estimate the differences between the preand intra-operative anatomical features, their effect on the model-to-subject registration, and also identify the need to update or optimize any pre-operative surgical plan to better suit the intra-operative procedure workflow.

  19. Catecholaminergic Gene Polymorphisms Are Associated with GI Symptoms and Morphological Brain Changes in Irritable Bowel Syndrome

    PubMed Central

    Shih, Wendy; Presson, Angela P.; Hammer, Christian; Niesler, Beate; Heendeniya, Nuwanthi; Mayer, Emeran A.; Chang, Lin

    2015-01-01

    Background Genetic and environmental factors contribute to the pathophysiology of irritable bowel syndrome (IBS). In particular, early adverse life events (EALs) and the catecholaminergic system have been implicated. Aims To investigate whether catecholaminergic SNPs with or without interacting with EALs are associated with: 1) a diagnosis of IBS, 2) IBS symptoms and 3) morphological alterations in brain regions associated with somatosensory, viscerosensory, and interoceptive processes. Methods In 277 IBS and 382 healthy control subjects (HCs), 11 SNPs in genes of the catecholaminergic signaling pathway were genotyped. A subset (121 IBS, 209 HCs) underwent structural brain imaging (magnetic resonance imaging [MRI]). Logistic and linear regressions evaluated each SNP separately and their interactions with EALs in predicting IBS and GI symptom severity, respectively. General linear models determined grey matter (GM) alterations from the SNPs and EALs that were predictive of IBS. Results 1) Diagnosis: There were no statistically significant associations between the SNPs and IBS status with or without the interaction with EAL after adjusting for multiple comparisons. 2) Symptoms: GI symptom severity was associated with ADRA1D rs1556832 (P = 0.010). 3) Brain morphometry: In IBS, the homozygous genotype of the major ADRA1D allele was associated with GM increases in somatosensory regions (FDR q = 0.022), left precentral gyrus (q = 0.045), and right hippocampus (q = 0.009). In individuals with increasing sexual abuse scores, the ADRAβ2 SNP was associated with GM changes in the left posterior insula (q = 0.004) and left putamen volume (q = 0.029). Conclusion In IBS, catecholaminergic SNPs are associated with symptom severity and morphological changes in brain regions concerned with sensory processing and modulation and affect regulation. Thus, certain adrenergic receptor genes may facilitate or worsen IBS symptoms. PMID:26288143

  20. The thoracic limb of the suricate (Suricata suricatta): osteology, radiologic anatomy, and functional morphologic changes.

    PubMed

    van Staden, Sheryl L

    2014-09-01

    The purpose of the study was to identify unique features of the normal osteology and radiologic anatomy of the thoracic limb of the meerkat or suricate (Suricata suricatta), as no comprehensive information has been published. Bone specimens of 19 suricates were studied. Individual bones of the manus of one preserved carcass were studied in situ. Radiographic evaluation was performed in six animals. Comparisons to domestic carnivores were made and functional morphologic changes were identified. A suprahamate process was present on the scapula spine. Both supratrochlear and supracondylar foramina were present in the distal humerus, with a small Fossa coronoidea seen cranially. The medial epicondyle was markedly larger than the lateral epicondyle. The Tuberositas radii was located caudally. The proximal end of the olecranon was prominent medially. The large medial coronoid process had an extensive proximal articulation facet for the humeral trochlea. The ulna styloid process articulated with the ulnar and accessory carpal bones. The manus was similar to that of domestic carnivores; however, Os metacarpalis I was markedly reduced with the absence of the first digit. There were seven carpal bones. Os carpi radiale was the largest, with a large palmaro-medial process and a small sesamoid bone present medially. Ossa metacarpalia II-V and corresponding phalanges were slender, with an elongated Processus unguicularis (third phalanx) present. Radiologic findings demonstrated increased mobility of the scapula and shoulder joint, with ease of abduction. On the cranio-caudal view of the humerus and elbow joint, the distal radius and manus were consistently rotated in a supinated position. Morphologic changes were identified for the enhanced, predominant function of the shoulder, elbow, carpal, and digital flexor muscles associated with superior digging ability, and supination of the antebrachium and manus. Reference values for size parameters of the long bones are reported. The

  1. Morphological Changes Along a Dike Landside Slope Sampled by 4d High Resolution Terrestrial Laser Scanning

    NASA Astrophysics Data System (ADS)

    Herrero-Huertaa, Mónica; Lindenbergh, Roderik; Ponsioen, Luc; van Damme, Myron

    2016-06-01

    Emergence of light detection and ranging (LiDAR) technology provides new tools for geomorphologic studies improving spatial and temporal resolution of data sampling hydrogeological instability phenomena. Specifically, terrestrial laser scanning (TLS) collects high resolution 3D point clouds allowing more accurate monitoring of erosion rates and processes, and thus, quantify the geomorphologic change on vertical landforms like dike landside slopes. Even so, TLS captures observations rapidly and automatically but unselectively. In this research, we demonstrate the potential of TLS for morphological change detection, profile creation and time series analysis in an emergency simulation for characterizing and monitoring slope movements in a dike. The experiment was performed near Schellebelle (Belgium) in November 2015, using a Leica Scan Station C10. Wave overtopping and overflow over a dike were simulated whereby the loading conditions were incrementally increased and 14 successful scans were performed. The aim of the present study is to analyse short-term morphological dynamic processes and the spatial distribution of erosion and deposition areas along a dike landside slope. As a result, we are able to quantify the eroded material coming from the impact on the terrain induced by wave overtopping which caused the dike failure in a few minutes in normal storm scenarios (Q = 25 l/s/m) as 1.24 m3. As this shows that the amount of erosion is measurable using close range techniques; the amount and rate of erosion could be monitored to predict dike collapse in emergency situation. The results confirm the feasibility of the proposed methodology, providing scalability to a comprehensive analysis over a large extension of a dike (tens of meters).

  2. Morphological Changes in Subcutaneous White Adipose Tissue After Severe Burn Injury.

    PubMed

    Saraf, Manish Kumar; Herndon, David N; Porter, Craig; Toliver-Kinsky, Tracy; Radhakrishnan, Ravi; Chao, Tony; Chondronikola, Maria; Sidossis, Labros S

    2016-01-01

    Severe burn injury produces a plethora of metabolic abnormalities which contribute to the prolonged morbidity of burn survivors. The authors have recently demonstrated trans-differentiation of white adipose tissue (WAT) after burn trauma, toward a more thermogenic phenotype. However, the impact of burn injury on subcutaneous WAT (sWAT) morphology in humans is unknown. Here, the authors studied the effect of severe burn injury on the architecture of sWAT. sWAT was collected from 11 severely burned children (11 ± 3 years; 55 ± 16% total BSA burned) and 12 nonburned healthy children (9 ± 3 years). Histology, electron microscopy, immunohistochemistry, and immunofluorescence were performed on fixed adipose tissue sections. sWAT cytokine and collagen concentrations were measured by multiplex assay and sirius/fast green staining method, respectively. sWAT histology demonstrated multiple fat droplets, significantly (P < .05) reduced mean cell size (104 ± 6 vs 68 ± 3 μm) and higher collagen content (7 ± 0.8 vs 4 ± 0.4) in burn patients. sWAT from burn victims stained positive for CD68 suggesting infiltration of macrophages. Furthermore, electron microscopic analysis showed multiple fat droplets and greater mitochondrial abundance in sWAT of burn survivors. In agreement with this, mitochondrial respiratory capacity in the leak and coupled state increased by 100% in sWAT of burned children from 1 to 3 weeks postinjury. The cytokines IL-6, IL-8, IL-13, IL-1a, IL-1b, MCP-1, and TNF-α were all significantly greater in the sWAT of burned children versus healthy children (P < .05). Furthermore, IL-6, IL-8, IL1-a, IL-1b, and TNF-α significantly increased after injury in sWAT of burned children (P < .05). This study provides detailed evidence of morphological and functional changes in sWAT of burn survivors which was associated with tissue inflammation. A better understanding of morphological and functional changes in sWAT will help discern the mechanisms underlying

  3. Southern high latitude dune fields on Mars: Morphology, aeolian inactivity, and climate change

    USGS Publications Warehouse

    Fenton, L.K.; Hayward, R.K.

    2010-01-01

    In a study area spanning the martian surface poleward of 50?? S., 1190 dune fields have been identified, mapped, and categorized based on dune field morphology. Dune fields in the study area span ??? 116400km2, leading to a global dune field coverage estimate of ???904000km2, far less than that found on Earth. Based on distinct morphological features, the dune fields were grouped into six different classes that vary in interpreted aeolian activity level from potentially active to relatively inactive and eroding. The six dune field classes occur in specific latitude zones, with a sequence of reduced activity and degradation progressing poleward. In particular, the first signs of stabilization appear at ???60?? S., which broadly corresponds to the edge of high concentrations of water-equivalent hydrogen content (observed by the Neutron Spectrometer) that have been interpreted as ground ice. This near-surface ground ice likely acts to reduce sand availability in the present climate state on Mars, stabilizing high latitude dunes and allowing erosional processes to change their morphology. As a result, climatic changes in the content of near-surface ground ice are likely to influence the level of dune activity. Spatial variation of dune field classes with longitude is significant, suggesting that local conditions play a major role in determining dune field activity level. Dune fields on the south polar layered terrain, for example, appear either potentially active or inactive, indicating that at least two generations of dune building have occurred on this surface. Many dune fields show signs of degradation mixed with crisp-brinked dunes, also suggesting that more than one generation of dune building has occurred since they originally formed. Dune fields superposed on early and late Amazonian surfaces provide potential upper age limits of ???100My on the south polar layered deposits and ???3Ga elsewhere at high latitudes. No craters are present on any identifiable dune

  4. Applying Uav and Photogrammetry to Monitor the Morphological Changes Along the Beach in Penghu Islands

    NASA Astrophysics Data System (ADS)

    Lu, Cheng-Hao

    2016-06-01

    Penghu islands, in the southern Taiwan Strait, is a remnant of a middle-late Miocene basaltic shield volcano. We present a procedure to use UAV (Unmanned Aerial Vehicles) to perform photogrammetry survey and monitoring analysis in beach evolution scenarios. The aim of this study is to understand spatial-temporal change along the sandy beach in Penghu islands, especially as for the effects of typhoon and coastal structures. According to the study result, this example of application is provided to show the results and the potential of this methodology in real beach changes. In addition, we found the typhoon and coastal structures play important roles to shape the beach morphology and its evolution. The result of beach monitoring reveals that the reduction and change of sand volume in Shanshui beach resulted from the placement of detached breakwater complexes. This coastal structure likely resulted in the development of tombolo and therefor make the beach unstable and subject to conduct rip current and more erosion.

  5. Morphological and nanostructural surface changes in Escherichia coli over time, monitored by atomic force microscopy.

    PubMed

    Gammoudi, Ibtissem; Mathelie-Guinlet, Marion; Morote, Fabien; Beven, Laure; Moynet, Daniel; Grauby-Heywang, Christine; Cohen-Bouhacina, Touria

    2016-05-01

    The present study aims at evaluating intrinsic changes in Escherichia coli (E. coli) surface over time, by Atomic Force Microscopy (AFM). For that purpose, bacteria were immobilized on mica or on mica previously functionalized by the deposition of a polyelectrolyte multilayer cushion. AFM images reveal that E. coli population goes through different stages. Firstly, after a week, the number of healthy bacteria decreases resulting in a release of cellular components which likely become, in turn, a nutrition source for increasing the healthy population after around two weeks. Finally, after one month, most of the bacteria is dead. Our study shows a transition of a healthy rod-shaped bacterium to a dead collapsed one. Most importantly, along with the morphological evolution of bacteria, are the structure changes and the mechanical properties of their outer membrane, emphasized by AFM phase images with very high resolution. Indeed, the surface of healthy bacteria is characterized by a phase separation pattern, thereafter mentioned as "ripples". Bacterial ageing goes along with the loss of this organized structure, turning into circular areas with irregular boundaries. These changes are likely caused by a re-organization, due to external stress, of mainly lipopolysaccharides (LPS) present in the outer membrane of E. coli. PMID:26878286

  6. Morphological Changes in Mesenteric Lymph Nodes and Lymphocyte Subpopulation Composition in Experimental Ulcerative Colitis.

    PubMed

    Postovalova, E A; Khochansky, D N; Zolotova, N A; Gao, Yu; Makarova, O V; Dobrynina, M T

    2016-04-01

    Morphological changes in the mesenteric lymph nodes of male C57Bl/6 mice and subpopulation composition of lymphocytes in these nodes were studied in experimental acute and chronic ulcerative colitis induced by sodium dextran sulfate. Acute and chronic ulcerative colitis was associated with the development of reactive changes in the mesenteric lymph nodes. These changes were of mixed type and were characterized by follicular hyperplasia and sinus reaction. The content of CD19(+) B cells in the mesenteric lymph nodes decreased in acute ulcerative colitis, while the content of CD3(+)CD8(+) cytotoxic T cells increased, which presumably reflected activation of Th1 reactions. The increase in the count of CD4(+)CD25(+)FOXP3(+) regulatory T cells and CD3(+)CD8(+) cytotoxic T cells was due to intensive migration of lymphocytes from the thymus and the colonic compartment of the local immune system. Chronic ulcerative colitis was associated with higher levels of CD19(+) B cells and CD3(+)CD4(+) T helper cells in the mesenteric lymph nodes, which was characteristic of adoptive immunity reactions and chronization of the inflammatory process. PMID:27165070

  7. Epidermal changes in heat and electrically injured pig skin: a light microscopic study of the sequences in morphology.

    PubMed

    Thomsen, H K; Danielsen, L; Nielsen, O; Aalund, O; Nielsen, K G; Karlsmark, T; Genefke, I K

    1982-09-01

    Biopsies were obtained from heat and electrically exposed pig skin at different at different times after exposure, in order to describe the morphological sequences in heat and electrically injured skin. The work is part of a series of studies in which it is investigated whether morphological methods can be used in disclosing electrical torture. Epidermal changes in heat lesions differed from those of electrical lesions in all experiments. Heat lesions typically showed a detached epidermis with fibrillar or granular cytoplasm. In older lesions the epidermis appeared concrete. Electrical lesions showed an attached epidermis with small defects, a white, homogeneous cytoplasm, vesicular nuclei and curled, clumped keratin. The electrical lesions were rejected at day 4 or 5. The number of characteristic morphological changes in epidermis decreased with the age of the lesions. It is concluded that epidermal electrical lesions differ in morphology from heat lesions and that it is possible to evaluate the age of the lesions. PMID:7148451

  8. FoxP2 protein levels regulate cell morphology changes and migration patterns in the vertebrate developing telencephalon.

    PubMed

    Garcia-Calero, Elena; Botella-Lopez, Arancha; Bahamonde, Olga; Perez-Balaguer, Ariadna; Martinez, Salvador

    2016-07-01

    In the mammalian telencephalon, part of the progenitor cells transition from multipolar to bipolar morphology as they invade the mantle zone. This associates with changing patterns of radial migration. However, the molecules implicated in these morphology transitions are not well known. In the present work, we analyzed the function of FoxP2 protein in this process during telencephalic development in vertebrates. We analyzed the expression of FoxP2 protein and its relation with cell morphology and migratory patterns in mouse and chicken developing striatum. We observed FoxP2 protein expressed in a gradient from the subventricular zone to the mantle layer in mice embryos. In the FoxP2 low domain cells showed multipolar migration. In the striatal mantle layer where FoxP2 protein expression is higher, cells showed locomoting migration and bipolar morphology. In contrast, FoxP2 showed a high and homogenous expression pattern in chicken striatum, thus bipolar morphology predominated. Elevation of FoxP2 in the striatal subventricular zone by in utero electroporation promoted bipolar morphology and impaired multipolar radial migration. In mouse cerebral cortex we obtained similar results. FoxP2 promotes transition from multipolar to bipolar morphology by means of gradiental expression in mouse striatum and cortex. Together these results indicate a role of FoxP2 differential expression in cell morphology control of the vertebrate telencephalon. PMID:26163006

  9. Multi-temporal image analysis for river reach morphological changes identification

    NASA Astrophysics Data System (ADS)

    Giordan, Daniele; Franzi, Luca; Rinaldi, Stefano; Dutto, Furio; Baldo, Marco; Allasia, Paolo

    2016-04-01

    The study of river reach evolution can be very important for the definition of the level of risk of building and infrastructures that are located nearby. Usually, these studies are based on the use of aerial photos and/or LiDAR surveys that could be analyzed for the definition of the river reach boundaries and their evolution over the time. In the past, the typical approach was the use of aerial photo for the identification of main morphological elements of the river and the definition of their changes over the time. LiDAR systems introduced an important add value related to the possibility to acquire also a DTM of the studied area and not only an orthophoto. The comparison of DTMs acquired in different periods can be useful for the identification of the changes in altimetry that can be a very important element for the comprehension of the morphological evolution of the studied area. When a river reach is characterized by a frequent changes in time, a detailed investigation needs frequent surveys and mapping. In this frame the recourse to frequent use of LiDAR could be very expensive, and therefore other cheaper solutions can be preferable. The use of RPAS system can be considered a good means for the acquisition of orthophoto and digital surface models, expecially for limited portions of river reaches and for the most active sectors. The high resolution of the orthophoto and the DSM are two important products that can be used for the identification and the measurement of main morphological changer of a river reach. The combination of aerial photos, LiDAR surveys and RPAS acquisition has been tested on the Orco River, Piemonte region (NW Italy). Orco is a gravel multichannel river with several sectors characterized by a strong inclination to the wandering of the main channel. One of the most critical sector is located not far from the confluence with Po River, where the wandering of the main channel changed the direction of the main flux of the water that now risks

  10. A Morphology Independent Methodology for Quantifying River Planform Change and Characteristics from Remotely Sensed Imagery

    NASA Astrophysics Data System (ADS)

    Rowland, J. C.; Gangodagamage, C.; Shelef, E.; Pope, P. A.; Brumby, S. P.; Wilson, C. J.

    2014-12-01

    The ready availability of remotely sensed imagery offers the potential to examine river dynamics and planform characteristics at global scales. The Landsat archive currently offers the greatest spatial and temporal coverage of the entire globe. However, at 30 meter multispectral resolution detailed and accurate examination of planform changes using Landsat imagery is restricted to intermediate (~ 500 m wide) to very large (~ 1 km wide) rivers or smaller rivers with very high rates of change. Many of these larger river systems exhibit multi-threaded or braided channel patterns that present significant challenges for many of the existing methodologies for quantifying changes developed for single threaded meandering river systems. In order to examine planform changes in river systems across all scales and morphologies we developed a set of algorithms for quantifying river mobility and planform attributes using raster-based river masks extracted from remotely sensed data. Unlike many prior methodologies for measuring river migration and erosion that rely on changes in the position of river channel centerlines, our methods adopt river banks as a frame of reference for quantifying change. The choice of a bank-centric reference frame was motivated by both a primary interest in the spatial and temporal patterns of bank change and the significant challenge of extracting and comparing channel centerlines in multi-threaded systems. Unlike prior vector-based analysis of river channels, our analysis retains a raster-based representation of the river from the original imagery source. At each bank pixel, our algorithms compute linear rates of bank change, local channel width, bank curvature, and bank aspect (used for examination of the influence of thermal processes such as freeze thaw and permafrost influence). The spatially distributed measurements are also aggregated along equally spaced river segments to examine spatial patterns in erosion/accretion rates, and channel widths

  11. Modelling long term morphological changes with XBeach: case study of Kizilirmak River mouth, Turkey

    NASA Astrophysics Data System (ADS)

    Baykal, Cüneyt; Ergin, Aysen; Güler, Işıkhan; Özyurt Tarakcıoğlu, Gülizar; Söğüt, Erdinç; Gökhan Güler, Hasan; Güney Doğan, Gözde

    2015-04-01

    The Bafra alluvial plain, where the Kızılırmak River discharges into the Black Sea, is one of the most critical examples of severe coastal erosion problems in Turkey. The amount of sediment carried by the Kızılırmak River has decreased from approximately 23 million ton per year to 0.46 million tons/year starting from 1960s as a result of construction of flow regulatory structures in the following years. This drastic decrease in the amount of sediment carried by the river resulted in a severe shoreline retreat up to 1 km in the cross-shore direction since 1988 according to the Regional Directorate of State Hydraulic Works and local residents (Kökpınar et al., 2007). The first remedial measure against this severe coastal erosion problem at the river mouth was constructed in 2000 by State Hydraulic Works (DSİ). It was composed of two Y-type and one I-type groins constructed at the eastern shoreline of the river mouth. After construction of the first remedial system, the shoreline retreat slowed down between the groins and trapping of sediment initiated. Today, the gaps between the groins are almost completely filled with sediment. In this study, the shoreline changes between the groins of the first remedial system for the years 1999, 2003 and 2007 are studied using the open source numerical model called XBeach (Roelvink et al.2010) focusing on the hydrodynamics and tombolo formation around the groins. The numerical model has been developed mainly to model short term morphological changes such as nearshore responses under storm and hurricane conditions. Herein, the preparation of the wave data input to minimize the computational demand of the model and the effect of the sequence of the input wave directions are discussed in detail in this study. Finally, the shoreline changes obtained from numerical model simulations are compared with the field data. Keywords: Numerical modeling of shoreline changes, tombolo formation

  12. Influence of Climate Change on Wave Dissipation over Coral Reefs: Effects on Beach Morphology

    NASA Astrophysics Data System (ADS)

    Grady, A. E.; Moore, L. J.; Storlazzi, C. D.; Elias, E.; Reidenbach, M. A.

    2012-12-01

    Coral reefs play a critical role in protecting coastlines by dissipating wave energy as it approaches shore. However, anthropogenic alterations to reef systems, such as changes in species composition, growth rates, and reef morphology, in combination with sea-level rise, have the potential to significantly alter wave dissipation across reefs. Changes in wave dissipation may lead to shifts in alongshore sediment transport gradients, thereby altering patterns of erosion and accretion on tropical coastlines. To simulate the effects of reef degradation on sediment transport rates, we used Delft3D to consider two schematized profile model domains based on a stretch of coast from Molokai, Hawaii. We created two representative end-member reef flat widths and simulated the incremental degradation, represented by an increase in overall depth, of the fore reef and reef crest structure (-0.10, -0.25, -0.50, and -1.00 m), as well as potential sea-level rise scenarios (+0.10, +0.25, +0.50, and +1.00 m). Resulting significant wave heights and alongshore sediment transport rates during storm conditions were compared across simulations for the two domains. Preliminary findings indicate that over a wide reef flat, sea-level rise has a greater relative effect than reef degradation on wave energy and alongshore sediment transport rates. In contrast, on narrow reef flats, the effects of reef degradation and sea-level rise are of the same order of magnitude. Further, because narrow reef flats are likely more sensitive to changes in coral reef degradation, our results suggest that reefs having alongshore-variable widths are most likely to experience changes in alongshore sediment transport gradients, and therefore shifts in patterns of erosion and accretion, than more linear fringing reef systems.

  13. Functional and morphological changes in pig skin after single or fractionated doses in x rays

    SciTech Connect

    Young, C.M.A.; Hopewell, J.W.

    1982-09-01

    The flank skin of pigs has been treated with either single or fractionated doses of x-irradiation. A single dose (2070 cGy) was compared with treatment given as 6 fractions in 18 days (6f/18 days; 3780 cGy) or 30 fractions in 39 days (30f/39 days; 8000 cGy). The doses were selected on the basis that similar levels of late tissue damage would result. Radiation induced changes in the skin were assessed by observing the skin reactions and by the measurement of isotope clearance (functional study), relative field contraction, dermal and epidermal thickness and dermal vascular density (morphological studies). In the three treatment groups the early radiation reaction varied considerably. In the first wave reaction (3 to 6 weeks after treatment) bright red erythema was recorded in many fields but moist desquamation developed only in the 30f/39 days treatment group. The second wave (10-16 weeks) was characterized by an ischemic mauve/dusky reaction. Dermal necrosis developed in 50% of the single dose fields. In the 30f/39 days regimen persistent moist desquamation progressed to dermal necrosis. Neither desquamation nor necrosis developed after 6f/18 days. Different levels of vascular damage in the dermis were assessed using an isotope clearance technique; for example in the early reaction significant changes were recorded in the papillary dermis (faster clearance) prior to the development of moist desquamation (30f/39 days) and in the reticular dermis (slower clearance) before necrosis (single dose). Changes in clearance rates have been correlated with changes in the vascular density and thickness of the dermis. Between 26 and 52 weeks (the late reaction) relative field contraction was slightly greater in the 30f/39 days group than in the other treatment groups.

  14. Critical storm thresholds for significant morphological changes and damage along the Emilia-Romagna coastline, Italy

    NASA Astrophysics Data System (ADS)

    Armaroli, Clara; Ciavola, Paolo; Perini, Luisa; Calabrese, Lorenzo; Lorito, Samantha; Valentini, Andrea; Masina, Marinella

    2012-03-01

    period surge are able to erode and/or overwash 2/3 of the dunes. The historical storm hydrodynamic information was used to estimate which wave and surge conditions are able to inundate at least 2/3 of the beach profiles. The MWL was again compared to beach elevations, this time along 63 anthropogenic profiles spaced 500 m apart (or 1/3 of the urbanised coastline). It was found that a wave heights >= 2 m and surge + tide levels >= 0.7 m are able to flood between 18% and 36% of the built-up coast. The defined thresholds are related to the present coastal characteristics and are not "static", meaning that they are likely to change according to future evolution of the coastline. They are very important because they can be used as thresholds to issue warnings and alert the Civil Protection. Moreover they are the first thresholds defined for the Emilia-Romagna coastline and will be used as starting values to generate "dynamic" thresholds based on numerical model predictions of morphological change for a given wave and surge level.

  15. Morphological and histological changes in digestive tract development during starvation in the miiuy croaker.

    PubMed

    Shan, Xiujuan; Quan, Hanfeng; Dou, Shuozeng

    2016-04-01

    A histological method was used to describe the ontogenetic development of the digestive tract of laboratory-reared miiuy croaker (Miichthys miiuy) and to evaluate the effects of short-term food deprivation on the morphology and histology of the digestive tract. Larvae and juveniles were maintained at 24 °C in a thermostatically controlled system. Three starvation experiments were conducted during different developmental stages: 1-7 days after hatching (dah; prior to benthic swimming); 26-35 dah (during settling); and 42-53 dah (after benthic swimming). According to the structural changes in the ontogenetic development of the digestive tract, three stages were observed. The first stage was from hatching to 3 dah; the digestive tract was undifferentiated in newly hatched larvae and then showed remarkable morphological changes and differentiation. During this period, larvae depended on endogenous nutrition. The second stage (4-20 dah) was a critical period in which larvae transitioned from endogenous feeding to exogenous feeding and the digestive tract fully differentiated into the buccopharynx, oesophagus, stomach, anterior intestine and posterior intestine. Goblet cells and vacuoles appeared in the digestive tract, and pharyngeal teeth and taste buds developed. During the third stage (20-36 dah), the gastric glands developed and the stomach differentiated into the fundic, cardiac and pyloric regions. At 25 dah, pyloric caeca developed and mucosal folds and spiral valves were clearly distinguishable. After 30 dah, the digestive tract did not undergo any noticeable differentiation, indicating the complete development of the digestive system. The wet weight and SGR (specific growth rate) of miiuy croaker larvae and juveniles greatly decreased when they were deprived of food, and compensatory growth was observed in re-feeding juveniles. The livers of starved larvae and juveniles were atrophied and dark coloured, the intestines were transparent and thin, and the stomach

  16. Chronic aerobic swimming exercise promotes functional and morphological changes in rat ileum

    PubMed Central

    da Cunha Araujo, Layanne Cabral; de Souza, Iara Leão Luna; Vasconcelos, Luiz Henrique César; de Freitas Brito, Aline; Queiroga, Fernando Ramos; Silva, Alexandre Sérgio; da Silva, Patrícia Mirella; de Andrade Cavalcante, Fabiana; da Silva, Bagnólia Araújo

    2015-01-01

    Several studies have reported the gastrointestinal (GI) effects promoted by the physical exercise. Thus, we aimed to evaluate the influence of swimming exercise on the contractile reactivity, lipid peroxidation and morphology of rat ileum. Wistar rats were divided into sedentary (SED) and groups exercised for two (EX2), four (EX4), six (EX6) or eight (EX8) weeks, 5 days/week. Animals were killed; the ileum was removed and suspended in organ baths where the isotonic contractions were recorded. Lipid peroxidation was evaluated by MDA (malondialdehyde) measurement with TBARS (thiobarbituric acid reactive substances) assay and morphology by histological staining. Cumulative concentration-response curves to KCl were attenuated, as the Emax values were changed from 100% (SED) to 63.1±3.9 (EX2), 48.8±3.8 (EX4), 19.4±1.8 (EX6) and 59.4±2.8% (EX8). Similarly, cumulative concentration-response curves to carbamylcholine hydrochloride (CCh) were attenuated, as the Emax values were changed from 100% (SED) to 74.1±5.4 (EX2), 75.9±5.2 (EX4) and 62.9±4.6 (EX6), but not in the EX8 (89.7±3.4%). However, CCh potency was increased in this latter, as the EC50 was altered from 1.0±0.1×10−6 (SED) to 2.1±0.4×10−7 (EX8). MDA concentration was altered only in EX4 (44.3±4.4) compared with SED (20.6±3.6 μmol/l). Circular layer was reduced in SED when compared with the exercised groups. Conversely, longitudinal layer was increased. In conclusion, chronic swimming exercise reduces the ileum contraction, equilibrates the oxidative damage and promotes changes in tissue size to establish an adaptation to the exercise. PMID:26424698

  17. Age Related Changes in Craniofacial Morphology in GDF-8 (Myostatin) Deficient Mice

    PubMed Central

    Vecchione, Lisa; Miller, Jeffrey; Byron, Craig; Cooper, Gregory M.; Barbano, Timothy; Cray, James; Losee, Joseph E.; Hamrick, Mark W.; Sciote, James J.; Mooney, Mark P.

    2011-01-01

    It is well recognized that masticatory muscle function helps determine morphology, although the extent of function on final form is still debated. GDF-8 (myostatin), a transcription factor is a negative regulator of skeletal muscle growth. A recent study has shown that mice homozygous for the myostatin mutation had increased muscle mass and craniofacial dysmorphology in adulthood. However, it is unclear whether such dysmorphology is present at birth. This study examines the onset and relationship between hypermuscularity and craniofacial morphology in neonatal and adult mice with GDF-8 deficiency. Fifteen (8 wild-type and 7 GDF-8 −/−), 1 day old and 16 (9 wt and 7 GDF-8 −/−), 180 day old male CD-1 mice were used. Standardized radiographs were taken of each head, scanned, traced, and cephalometric landmarks identified. Significant mean differences were assessed using a group × age, two-way ANOVA. Myostatin-deficient mice had significantly (p<0.01) smaller body and masseter muscle weights and craniofacial skeletons at 1 day of age and significantly greater body and masseter muscle weights at 180 days of age compared to controls. Myostatin-deficient mice showed significantly (p<0.001) longer and “rocker-shaped” mandibles and shorter and wider crania compared to controls at 180 days. Significant correlations were noted between masseter muscle weight and all cephalometric measurements in 180 day old Myostatin-deficient mice. Results suggest in this mouse model, there may be both early systemic skeletal growth deficiencies and later compensatory changes from hypermuscularity. These findings reiterate the role that masticatory muscle function plays on the ontogeny of the cranial vault, base, and most notably the mandible. PMID:19899116

  18. Aluminium oxide nanoparticles induced morphological changes, cytotoxicity and oxidative stress in Chinook salmon (CHSE-214) cells.

    PubMed

    Srikanth, Koigoora; Mahajan, Amit; Pereira, Eduarda; Duarte, Armando Costa; Venkateswara Rao, Janapala

    2015-10-01

    Aluminium oxide nanoparticles (Al2 O3 NPs) are increasingly used in diverse applications that has raised concern about their safety. Recent studies suggested that Al2 O3 NPs induced oxidative stress may be the cause of toxicity in algae, Ceriodaphnia dubia, Caenorhabditis elegans and Danio rerio. However, there is paucity on the toxicity of Al2 O3 NPs on fish cell lines. The current study was aimed to investigate Al2 O3 NPs induced cytotoxicity, oxidative stress and morphological abnormality of Chinnok salmon cells (CHSE-214). A dose-dependent decline in cell viability was observed in CHSE-214 cells exposed to Al2 O3 NPs. Oxidative stress induced by Al2 O3 NPs in CHSE-214 cells has resulted in the significant reduction of superoxide dismutase, catalase and glutathione in a dose-dependent manner. However, a significant increase in glutathione sulfo-transferase and lipid peroxidation was observed in CHSE-214 cells exposed to Al2 O3 NPs in a dose-dependent manner. Significant morphological changes in CHSE-214 cells were observed when exposed to Al2 O3 NPs at 6, 12 and 24 h. The cells started to detach and appear spherical at 6 h followed by loss of cellular contents resulting in the shrinking of the cells. At 24 h, the cells started to disintegrate and resulted in cell death. Our data demonstrate that Al2 O3 NPs induce cytotoxicity and oxidative stress in a dose-dependent manner in CHSE-214 cells. Thus, our current work may serve as a base-line study for future evaluation of toxicity studies using CHSE-214 cells. PMID:25875951

  19. EVOLUTION OF THE RADIO REMNANT OF SUPERNOVA 1987A: MORPHOLOGICAL CHANGES FROM DAY 7000

    SciTech Connect

    Ng, C.-Y.; Zanardo, G.; Potter, T. M.; Staveley-Smith, L.; Gaensler, B. M.; Manchester, R. N.; Tzioumis, A. K.

    2013-11-10

    We present radio imaging observations of supernova remnant 1987A at 9 GHz, taken with the Australia Telescope Compact Array over 21 years from 1992 to 2013. By employing a Fourier modeling technique to fit the visibility data, we show that the remnant structure has evolved significantly since day 7000 (mid-2006): the emission latitude has gradually decreased such that the overall geometry has become more similar to a ring structure. Around the same time, we find a decreasing trend in the east-west asymmetry of the surface emissivity. These results could reflect the increasing interaction of the forward shock with material around the circumstellar ring, and the relative weakening of the interaction with the lower-density material at higher latitudes. The morphological evolution caused an apparent break in the remnant expansion measured with a torus model, from a velocity of 4600{sup +150}{sub -}200 km s{sup –1} between day 4000 and 7000 to 2400{sup +100}{sub -200} km s{sup –1} after day 7000. However, we emphasize that there is no conclusive evidence for a physical slowing of the shock at any given latitude in the expanding remnant, and that a change of radio morphology alone appears to dominate the evolution. This is supported by our ring-only fits which show a constant expansion of 3890 ± 50 km s{sup –1} without deceleration between days 4000 and 9000. We suggest that once the emission latitude no longer decreases, the expansion velocity obtained from the torus model should return to the same value as that measured with the ring model.

  20. Channel Morphological Changes in the Yuba River, California, in the Post-Hydraulic Mining Period

    NASA Astrophysics Data System (ADS)

    Ghoshal, S.; James, A.; Singer, M.; Aalto, R.

    2007-12-01

    Hydraulic gold mining in the Sierra Nevada of California (1853-1884) produced large volumes of sediment from upland placer gravels. The prevailing belief has been that piedmont storage of this sediment is volumetrically negligible or inactive. This study tests the hypothesis that large deposits of historical sediment remaining in the bed, banks and terraces of the lower Yuba River have been remobilized by floods and that erosion has continued over the past few decades. Remote sensing and GIS analyses of topographic and planimetric data from historical maps, surveys, aerial photographs, and LiDAR data document historic changes and the timing of sediment erosion and deposition within the channel and floodplain system. Planimetric and volumetric measurements of channel enlargement, lateral migration, avulsions, and channel filling provide magnitudes of erosion and deposition of historic sediments in the lower Yuba River. In 1906, the California Debris Commission produced a detailed large-scale topographic map of the lower Yuba floodplain showing it as a multi-thread channel system. The paleochannel scars remain evident on air photos, LiDAR images, and in the field. Differencing of topographic data derived from the 1906 topographic maps and 1999 LiDAR data provide volumetric measures of substantial channel morphologic changes including channel shifting, filling, and evolution towards a single- thread channel system. These measures identify processes and rates of sediment production relevant to broader issues of flood hazards in the region.

  1. Ocean acidification induces biochemical and morphological changes in the calcification process of large benthic foraminifera.

    PubMed

    Prazeres, Martina; Uthicke, Sven; Pandolfi, John M

    2015-03-22

    Large benthic foraminifera are significant contributors to sediment formation on coral reefs, yet they are vulnerable to ocean acidification. Here, we assessed the biochemical and morphological impacts of acidification on the calcification of Amphistegina lessonii and Marginopora vertebralis exposed to different pH conditions. We measured growth rates (surface area and buoyant weight) and Ca-ATPase and Mg-ATPase activities and calculated shell density using micro-computer tomography images. In A. lessonii, we detected a significant decrease in buoyant weight, a reduction in the density of inner skeletal chambers, and an increase of Ca-ATPase and Mg-ATPase activities at pH 7.6 when compared with ambient conditions of pH 8.1. By contrast, M. vertebralis showed an inhibition in Mg-ATPase activity under lowered pH, with growth rate and skeletal density remaining constant. While M. vertebralis is considered to be more sensitive than A. lessonii owing to its high-Mg-calcite skeleton, it appears to be less affected by changes in pH, based on the parameters assessed in this study. We suggest difference in biochemical pathways of calcification as the main factor influencing response to changes in pH levels, and that A. lessonii and M. vertebralis have the ability to regulate biochemical functions to cope with short-term increases in acidity. PMID:25694619

  2. Morphological change in the corneal endothelium due to ultraviolet radiation in welders.

    PubMed Central

    Karai, I; Matsumura, S; Takise, S; Horiguchi, S; Matsuda, M

    1984-01-01

    To clarify the relationship between morphological changes in the corneal endothelium and ultraviolet (UV) radiation, specular microscopic examinations were performed on both eyes of 118 welders and 85 controls. The results showed: a decrease in the hexagonal cells in welders (20-29 years) in comparison with the controls (20-29) (p less than 0.05); an increase in the mean cell size of the endothelium and a decrease in the hexagonal cell population with increasing age in both groups; increases in standard deviation (SD) and the coefficient of variation (CV) of the mean cell size in both groups; increases in SD and CV of the mean number of cell cell sides in both groups; and no difference in the mean cell size between the two groups. These results show that UV radiation damages not only the corneal epithelium but also the endothelium, and suggest that it causes more pleomorphic change (a decrease in hexagonal cell population) than enlargement of the mean cell size. Images PMID:6743623

  3. Examination of changes in the morphology of lignocellulosic fibers treated with e-beam irradiation

    NASA Astrophysics Data System (ADS)

    Gryczka, Urszula; Migdal, Wojciech; Chmielewska, Dagmara; Antoniak, Magdalena; Kaszuwara, Waldemar; Jastrzebska, Agnieszka; Olszyna, Andrzej

    2014-01-01

    Ionizing radiation was applied as a substrate pretreatment method in the process of bioethanol production. The aim of the presented work was to determine the changes in the morphology of willow plant fibers caused by the interaction of a high energy electron beam with lignocellulosic biomass. The microstructure was examined with a scanning electron microscope and X-ray computer microtomography. Additionally, sorption analysis was carried out in order to determine specific surface area and porosity. The analysis carried out after the treatment of lignocellulose with an electron beam indicated destruction of cell walls, observed as a decrease in the smoothness and an increase in the roughness of the surface of the fibers. The changes in surface texture and fiber integrity affected the specific surface area and porosity of the tested samples. The specific surface area, the total volume of pores and the average pore diameter were calculated based on the isotherms of nitrogen sorption. The increase in the specific surface area was observed to occur simultaneously with the increase in the average diameter of pores.

  4. Induction of Morphological Changes in Human Embryo Liver Cells by the Pyrrolizidine Alkaloid Lasiocarpine

    PubMed Central

    Armstrong, Sylvia J.; Zuckerman, A. J.; Bird, R. G.

    1972-01-01

    The pyrrolizidine alkaloids have been implicated in the aetiology of liver disease in man and in animals. Studies of the effects of lasiocarpine indicate that they have several and perhaps independent effects on human liver cells in culture. These may be summarized as follows: 1. Nuclear and nucleolar changes which are probably related to the alkylation of DNA and ensuing inhibition of nucleic acid and protein synthesis. 2. The induction of possible chromosomal damage and mutation. 3. A generalized reduction of the metabolic activities of the cells due to membrane and mitochondrial damage, and to alkylation and inactivation of cell enzymes and proteins. 4. A long-term inhibition of mitosis leading to the formation of giant cells (“megalocytes”). The morphological effects induced by a number of the pyrrolizidine alkaloids were very similar but the pattern of metabolic changes varied somewhat. It is believed that the hepatotoxic effects are not due to the pyrrolizidine alkaloids themselves but to metabolic derivatives formed by the cell. ImagesFigs. 3-5Figs. 1-2 PMID:5032090

  5. Morphological changes in the seminal receptacle during ovarian development in the speckled swimming crab Arenaeus cribrarius.

    PubMed

    Zara, Fernando Jose; Raggi Pereira, Gerson Rodrigues; Sant'anna, Bruno Sampaio

    2014-08-01

    To understand sperm plug dissolution and spermatophore dehiscence in Portunidae, histological and ultrastructural changes in the seminal receptacle (SR) of Arenaeus cribrarius were investigated during ovarian development. In juvenile females the SR was filled with acid polysaccharides and the dorsal epithelium was stratified. Mated females with rudimentary ovaries showed a large SR filled by a glycoprotein sperm plug. This plug was present until the developing-ovary stage, when spermatophore dehiscence and intense holocrine secretions in the dorsal dense layer occurred. The plug was absent after the intermediate stage, and the SR became flaccid. The secretion produced moved the spermatophores into the ventral region. The modified dorsal epithelium in the transition between the dorsal and ventral regions released acid polysaccharides, which were found among the sperm, by exocytosis. The morphological changes of the SR in A. cribrarius, including the presence of the sperm plug, followed the macroscopic pattern observed in other members of Portunidae, such as blue crabs. However, in this species dissolution of the sperm plug was synchronized with ovarian development and occurred simultaneously with spermatophore dehiscence, showing the evolutionary relationship of the seminal receptacle and the female reproductive system to the storage of spermatophores and spermatozoa. PMID:25216499

  6. Scanning electrochemical microscopy of model neurons: imaging and real-time detection of morphological changes.

    PubMed

    Liebetrau, Johanna M; Miller, Heather M; Baur, John E; Takacs, Sara A; Anupunpisit, Vipavee; Garris, Paul A; Wipf, David O

    2003-02-01

    Living PC12 cells, a model cell type for studying neuronal function, were imaged using the negative feedback mode of a scanning electrochemical microscope (SECM). Six biocompatible redox mediators were successfully identified from a large pool of candidates and were then used for imaging PC12 cells before and after exposure to nerve growth factor (NGF). When exposed to NGF, cells differentiate into a neuron phenotype by growing narrow neurites (1-2 microm wide) that can extend > 100 microm from the cell proper. We demonstrate that carbon fiber electrodes with reduced tip diameters can be used for imaging both the cell proper and these neurites. Regions of decreased current, possibly resulting from raised features not identifiable by light microscopy, are clearly evident in the SECM images. Changes in the morphology of undifferentiated PC12 cells could be detected in real time with the SECM. After exposure to hypotonic and hypertonic solutions, reversible changes in cell height of <2 microm were measured. PMID:12585485

  7. Ocean acidification induces biochemical and morphological changes in the calcification process of large benthic foraminifera

    PubMed Central

    Prazeres, Martina; Uthicke, Sven; Pandolfi, John M.

    2015-01-01

    Large benthic foraminifera are significant contributors to sediment formation on coral reefs, yet they are vulnerable to ocean acidification. Here, we assessed the biochemical and morphological impacts of acidification on the calcification of Amphistegina lessonii and Marginopora vertebralis exposed to different pH conditions. We measured growth rates (surface area and buoyant weight) and Ca-ATPase and Mg-ATPase activities and calculated shell density using micro-computer tomography images. In A. lessonii, we detected a significant decrease in buoyant weight, a reduction in the density of inner skeletal chambers, and an increase of Ca-ATPase and Mg-ATPase activities at pH 7.6 when compared with ambient conditions of pH 8.1. By contrast, M. vertebralis showed an inhibition in Mg-ATPase activity under lowered pH, with growth rate and skeletal density remaining constant. While M. vertebralis is considered to be more sensitive than A. lessonii owing to its high-Mg-calcite skeleton, it appears to be less affected by changes in pH, based on the parameters assessed in this study. We suggest difference in biochemical pathways of calcification as the main factor influencing response to changes in pH levels, and that A. lessonii and M. vertebralis have the ability to regulate biochemical functions to cope with short-term increases in acidity. PMID:25694619

  8. Morphological changes of Gumara River channel over 50 years, upper Blue Nile basin, Ethiopia

    NASA Astrophysics Data System (ADS)

    Abate, Mengiste; Nyssen, Jan; Steenhuis, Tammo S.; Moges, Michael M.; Tilahun, Seifu A.; Enku, Temesgen; Adgo, Enyew

    2015-06-01

    In response to anthropogenic disturbances, alluvial rivers adjust their geometry. The alluvial river channels in the upper Blue Nile basin have been disturbed by human-induced factors since a longtime. This paper examines channel adjustment along a 38-km stretch of the Gumara River which drains towards Lake Tana and then to the Blue Nile. Over a 50 years period, agriculture developed rapidly in the catchment and flooding of the alluvial plain has become more frequent in recent times. The objectives of this study were to document the changes in channel planform and cross-section of the Gumara River and to investigate whether the changes could have contributed to the frequent flooding or vice versa. Two sets of aerial photographs (1957 and 1980) were scanned, and then orthorectified. Recent channel planform information was extracted from SPOT images of 2006 and Google Earth. Channel planform and bed morphology (vertical changes) were determined for these nearly 50 years period. The vertical changes were determined based on aggradation along a permanent structure, historic information on river cross-sections at a hydrological gauging station, and field observations. The results indicate that the lower reach of Gumara near its mouth has undergone major planform changes. A delta with approx. 1.12 km2 of emerged land was created between 1957 and 1980 and an additional 1 km2 of land has been added between 1980 and 2006. The sinuosity of the river changed only slightly: negatively (-1.1% i.e. meandering decreased) for the period from 1957 to 1980 and positively (+3.0%) for the period 1980-2006. Comparison of cross-sections at the hydrological gauging station showed that the deepest point in the river bed aggraded by 2.91 m for the period 1963-2009. The importance of sediment deposition in the stream and on its banks is related to land degradation in the upper catchment, and to artificial rising of Lake Tana level that creates a backwater effect and sediment deposition in

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

    SciTech Connect

    Pingali, Sai Venkatesh; O'Neill, Hugh Michael; Nishiyama, Yoshiharu; He, Lilin; Melnichenko, Yuri B.; Urban, Volker S.; Petridis, Loukas; Davison, Brian H.; Langan, Paul

    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 in 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.

  10. AgNO3-Dependent Morphological Change of Si Nanostructures Prepared by Single-Step Metal Assisted Etching Method

    NASA Astrophysics Data System (ADS)

    Shimizu, Tomohiro; Yamaguchi, Takuya; Inoue, Fumihiro; Inada, Mitsuru; Shingubara, Shoso

    2012-11-01

    The morphological changes of a nanostructured Si surface prepared by metal assisted etching were investigated. We used a mixture of silver nitrate (AgNO3) and hydrofluoric acid (HF) as an electroless plating bath of Ag, as well as an etching solution of Si. With a change in silver ion concentration in the etching solution, three types of etched Si nanostructures were observed: “nanowire”, “porous wall”, and “polished”. We developed a phase diagram of the morphology of the etched Si surface. With increasing concentration of AgNO3 in the etching solution, the surface morphology of etched Si changes from nanowire to porous wall, and finally, polished for regardless of Si resistivity.

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

    DOE PAGESBeta

    Pingali, Sai Venkatesh; O'Neill, Hugh Michael; Nishiyama, Yoshiharu; He, Lilin; Melnichenko, Yuri B.; Urban, Volker S.; Petridis, Loukas; Davison, Brian H.; Langan, Paul

    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

  12. Infundibula of equine maxillary cheek teeth: Part 2: Morphological variations and pathological changes.

    PubMed

    Suske, A; Pöschke, A; Müller, P; Wöber, S; Staszyk, C

    2016-03-01

    Incomplete cemental filling of the infundibula of equine maxillary cheek teeth (CT) is a common feature. Depending on the extent of the defect, three stages of infundibular decay have been suggested. However, histomorphological criteria to identify non-pathological abnormalities and destructive changes have not been defined. Six hundred and eighty eight CT with no evidence of dental diseases and 55 diseased permanent, fully erupted maxillary CT were evaluated on a macroscopic level by assessing the occlusal surface and horizontal sections, including porphyrin assays to detect residual blood within the infundibular cementum. Selected specimens were investigated on a microscopic level using routine and immunohistological staining methods to identify possible routes for the spread of infectious agents from the infundibulum into the endodontic system. Infundibular cemental hypoplasia was defined as a non-pathological developmental abnormality and was detected in >50% of CT with no evidence of dental diseases and in >70% of diseased CT. The first molar (Triadan 09) showed the highest prevalence (75%) of infundibular cemental hypoplasia. The mesial infundibulum was more often affected than the distal infundibulum. Infundibular erosion was considered as the most appropriate term to describe destructive infundibular changes. Infundibular erosion was present in <6% of CT with no evidence of dental diseases, but was detected in >27% of diseased teeth, always accompanied by endodontic disease. This suggests that teeth affected by infundibular cemental hypoplasia are prone to destructive erosion, which possibly leads to endodontic disease. Morphological factors that supplement this ethological hypothesis were described. In 74% of infundibula residual blood was identified, although no vital blood vessels were detected. It is assumed that this content of blood remained in the ample infundibular cemental blood system after tooth eruption and creates a favorable environment for

  13. Differentially expressed genes and morphological changes during lengthened immobilization in rat soleus muscle.

    PubMed

    Kim, Ji Won; Kwon, Oh Yun; Kim, Myoung Hee

    2007-02-01

    To examine the effect of lengthened immobilization on the expression of genes and concomitant morphological changes in soleus muscle, rat hindlimbs were immobilized at the ankle in full dorsiflexion by plaster cast. After removing the muscle (after 1 hr, 1, 4, and 7 days of immobilization), morphology and differential gene expression were analyzed through electron microscopy and differential display reverse transcription-polymerase chain reaction (DDRT-PCR), respectively. At the myotendinous junction (MTJ), a large cytoplasmic space appeared after 1 hr of immobilization and became enlarged over time, together with damaged Z lines. Interfibrillar space was detected after 1 day of immobilization, but diminished after 7 days. At the muscle belly, Z-line streaming and widening were observed following 1 hr of immobilization. Disorganization of myofilaments (misalignment of adjacent sarcomeres, distortion, or absence of Z lines) was detected after 4 days. Furthermore, mitochondrial swelling and cristae disruption were observed after 1 day of stretching. A set of 15 differentially expressed candidate genes was identified through DDRT-PCR. Of 11 known genes, seven (Atp5g3, TOM22, INrf2, Slc25a4, Hdac6, Tpm1, and Sv2b) were up and three (Podxl, Myh1, and Surf1) were down-regulated following immobilization. In the case of Acyp2, 1-day stretching-specific expression was observed. Atp5g3, Slc25a4, TOM22, and Surf1 are mitochondrial proteins related to energy metabolism, except TOM22, which has a chaperone-like activity located in the mitochondrial outer membrane. Together with these, INrf2, Hdac6, Podxl, and Acyp2 are related more or less to stress-induced apoptosis, indicating the responses to apoptotic changes in mitochondria caused by stretching. The expression of both Tpm1 and Myh1, fast twitch isoforms, suggests adaption to the immobilization. These results altogether indicate that lengthened immobilization regulates the expression of several stress/apoptosis-related and

  14. Changes in morphology of Rhizopus chinensis in submerged fermentation and their effect on production of mycelium-bound lipase.

    PubMed

    Teng, Yun; Xu, Yan; Wang, Dong

    2009-04-01

    In order to control suitable mycelium morphology to obtain high lipase productivity by Rhizopus chinensis in submerged fermentation, the effects of fungal morphology on the lipase production by this strain both in shake flask and fermentor were investigated. Different inoculum level and shear stress were used to develop distinctive morphologies. Analyses and investigations both on micromorphology and macromorphology were performed. Study of micromorphology reveals that micromorphologies for dispersed mycelia and aggregated mycelia are different in cell shape, biosynthetic activity. Macromorphology and broth rheology study in fermentor indicate that pellet formation results in low broth viscosity. Under this condition, the oil can disperse sufficiently in broth which is very important for lipase production. These results indicate that morphology changes affected the lipase production significantly for R. chinensis and the aggregated mycelia were suggested to achieve high lipase production. PMID:18779980

  15. Changes in platelet morphology and function during 24 hours of storage.

    PubMed

    Braune, S; Walter, M; Schulze, F; Lendlein, A; Jung, F

    2014-01-01

    For in vitro studies assessing the interaction of platelets with implant materials, common and standardized protocols for the preparation of platelet rich plasma (PRP) are lacking, which may lead to non-matching results due to the diversity of applied protocols. Particularly, the aging of platelets during prolonged preparation and storage times is discussed to lead to an underestimation of the material thrombogenicity. Here, we study the influence of whole blood- and PRP-storage times on changes in platelet morphology and function. Blood from apparently healthy subjects was collected according to a standardized protocol and examined immediately after blood collection, four hours and twenty four hours later. The capability of platelets to adhere and form stable aggregates (PFA100, closure time) was examined in sodium citrate anticoagulated whole blood (WB) using the agonists equine type I collagen and epinephrine bitartrate (collagen/epinephrine) as well as equine type I collagen and adenosine-5'-diphosphate (collagen/ADP). Circulating platelets were quantified at each time point. Morphology of platelets and platelet aggregates were visualized microscopically and measured using an electric field multi-channel counting system (CASY). The percentage of activated platelets was assessed by means of P-selectin (CD62P) expression of circulating platelets. Furthermore, platelet factor 4 (PF4) release was measured in platelet poor plasma (PPP) at each time point. Whole blood PFA100 closure times increased after stimulation with collagen/ADP and collagen/epinephrine. Twenty four hours after blood collection, both parameters were prolonged pathologically above the upper limit of the reference range. Numbers of circulating platelets, measured in PRP, decreased after four hours, but no longer after twenty four hours. Mean platelet volumes (MPV) and platelet large cell ratios (P-LCR, 12 fL - 40 fL) decreased over time. Immediately after blood collection, no debris or platelet

  16. An analytical tool that quantifies cellular morphology changes from three-dimensional fluorescence images.

    PubMed

    Haass-Koffler, Carolina L; Naeemuddin, Mohammad; Bartlett, Selena E

    2012-01-01

    The most common software analysis tools available for measuring fluorescence images are for two-dimensional (2D) data that rely on manual settings for inclusion and exclusion of data points, and computer-aided pattern recognition to support the interpretation and findings of the analysis. It has become increasingly important to be able to measure fluorescence images constructed from three-dimensional (3D) datasets in order to be able to capture the complexity of cellular dynamics and understand the basis of cellular plasticity within biological systems. Sophisticated microscopy instruments have permitted the visualization of 3D fluorescence images through the acquisition of multispectral fluorescence images and powerful analytical software that reconstructs the images from confocal stacks that then provide a 3D representation of the collected 2D images. Advanced design-based stereology methods have progressed from the approximation and assumptions of the original model-based stereology even in complex tissue sections. Despite these scientific advances in microscopy, a need remains for an automated analytic method that fully exploits the intrinsic 3D data to allow for the analysis and quantification of the complex changes in cell morphology, protein localization and receptor trafficking. Current techniques available to quantify fluorescence images include Meta-Morph (Molecular Devices, Sunnyvale, CA) and Image J (NIH) which provide manual analysis. Imaris (Andor Technology, Belfast, Northern Ireland) software provides the feature MeasurementPro, which allows the manual creation of measurement points that can be placed in a volume image or drawn on a series of 2D slices to create a 3D object. This method is useful for single-click point measurements to measure a line distance between two objects or to create a polygon that encloses a region of interest, but it is difficult to apply to complex cellular network structures. Filament Tracer (Andor) allows automatic

  17. SEMINAL PROTEINS BUT NOT SPERM INDUCE MORPHOLOGICAL CHANGES IN THE DROSOPHILA MELANOGASTER FEMALE REPRODUCTIVE TRACT DURING SPERM STORAGE

    PubMed Central

    Adams, Erika M.; Wolfner, Mariana F.

    2007-01-01

    In most insects, sperm transferred by the male to the female during mating are stored within the female reproductive tract for subsequent use in fertilization. In Drosophila melanogaster, male accessory gland proteins (Acps) within the seminal fluid are required for efficient transfer and subsequent accumulation of sperm in the female's sperm storage organs. To determine the events within the female reproductive tract that occur during sperm storage, and the role that Acps and sperm play in these events, we identified morphological changes that take place during sperm storage in females mated to wild-type, Acp-deficient or sperm-deficient males. A reproducible set of morphological changes occurs in a wild-type mating. These were categorized into 10 stereotypic stages. Sperm are not needed for progression through these stages in females, but receipt of Acps is essential for progression beyond the first few stages of morphological changes. Furthermore, females that received small quantities of Acps reached slightly later stages than females that received no Acps. Our results suggest that timely morphological changes in the female reproductive tract, possibly muscular in nature, may be needed for successful sperm storage, and that Acps from the male are needed in order for these changes to occur. PMID:17276455

  18. Morphological and positional changes of the carpal arch and median nerve during wrist compression

    PubMed Central

    Marquardt, Tamara L.; Gabra, Joseph N.; Li, Zong-Ming

    2015-01-01

    Background The carpal tunnel is a fibro-osseous structure containing the median nerve and flexor tendons. Its cross-sectional area has been shown to increase during compressive force application to the carpal bones in modeling and in vitro studies. The purpose of this study was to investigate the morphological and positional changes of the carpal arch and median nerve while in vivo compressive force was applied in the radioulnar direction across the wrist. Methods Ultrasound images of the carpal tunnel and its contents were captured for 11 healthy, female volunteers at the distal tunnel level prior to force application and during force application of 10 and 20 N. Findings With applied force, the carpal arch width significantly decreased, while the carpal arch height and area significantly increased (P < 0.001). The median nerve shape became more rounded as the compressive force magnitude increased, reflected by decreases in the nerve’s flattening ratio and increases in its circularity (P < 0.001). The applied force also resulted in nerve displacement in the radial-volar direction. Interpretation This study demonstrates that noninvasively applying radioulnar compressive force across the wrist may potentially provide relief of median nerve compression to patients suffering from carpal tunnel syndrome. PMID:25661267

  19. Viability and morphological changes of Acanthamoeba spp. cysts after treatment with Effective microorganisms (EM).

    PubMed

    Sampaotong, Tanitta; Lek-Uthai, Usa; Roongruangchai, Jantima; Roongruangchai, Kosol

    2016-06-01

    Acanthamoeba is a free-living opportunistic protozoan parasite that is found in diverse environments. It can cause keratitis, mostly related to inappropriate use of contact lenses, as well as life threatening diseases including encephalitis, disseminated sinusitis, and skin ulcers. This study investigated morphological changes and fine structures of the cyst form of Acanthamoeba spp. after treatment with effective microorganisms (EM™) using light and scanning electron microscopies. Acanthamoeba cysts treated with 1:2, 1:4, 1:6, and undiluted EM™ showed higher percentages of non-viable cysts than those treated with 1:8, 1:10, 1:100, 1:200, and 1:400 EM™ and at 5 days post-treatment developed from cystic stage to trophozoite stage. Acanthamoeba cysts treated at concentrations of 1:2, 1:4, 1:6, and undiluted EM™ exhibited cytoplasmic clumping and shrinkage of amoeba cells away from cyst walls. The effective EM™ concentration lethal to Acanthamoeba spp. cyst could provide information to monitor the environmental control system. PMID:27413306

  20. Morphological changes in woody stem of Prunus jamasakura under simulated microgravity

    NASA Technical Reports Server (NTRS)

    Yoneyama, Emi; Ishimoto-Negishi, Yoko; Sano, Yuzou; Funada, Ryo; Yamada, Mitsuhiro; Nakamura, Teruko

    2004-01-01

    When the four-week-old woody stem of Prunus jamasakura was grown under simulated microgravity condition on a three-dimensional clinostat, it bent at growth, and width of its secondary xylem decreased due to the reduction of fiber cell numbers and a smaller microfibril angle in the secondary cell wall, as reported in our previous paper. Gravity induces the development of the secondary xylem that supports the stem upward against the action of gravity. In this study, morphological changes of the tissues and cells were microscopically observed. Disorder was found in the concentric structure of tissues that organize the stem. The radial arrangement of the cells was also disturbed in the secondary xylem, and in the secondary phloem secondary cell walls of the bast fiber cells were undeveloped. These findings suggest that differentiation and development of the secondary xylem and the bast fiber cells are strongly controlled by terrestrial gravity. These tissue and cells functions to support the stem under the action of gravity. Furthermore, clinorotation induced disorder in the straight joint of vessel elements and the lattice-like structure of radial parenchyma cells, which is responsible for water transportation and storage, respectively. Gravity is an essential factor for keeping the division and differentiation normal in woody stem.

  1. Search for Mechanically-Induced Grain Morphology Changes in Oxygen Free Electrolytic (OFE) Copper

    SciTech Connect

    Sanders, Jennifer; /SLAC

    2006-08-18

    The deformation of the microscopic, pure metal grains (0.1 to > 1 millimeter) in the copper cells of accelerator structures decreases the power handling capabilities of the structures. The extent of deformation caused by mechanical fabrication damage is the focus of this study. Scanning electron microscope (SEM) imaging of a bonded test stack of six accelerating cells at magnifications of 30, 100, 1000 were taken before simulated mechanical damage was done. After a 2{sup o}-3{sup o} twist was manually applied to the test stack, the cells were cut apart and SEM imaged separately at the same set magnifications (30, 100, and 1000), to examine any effects of the mechanical stress. Images of the cells after the twist were compared to the images of the stack end (cell 60) before the twist. Despite immense radial damage to the end cell from the process of twisting, SEM imaging showed no change in grain morphology from images taken before the damage: copper grains retained shape and the voids at the grain boundaries stay put. Likewise, the inner cells of the test stack showed similar grain consistency to that of the end cell before the twist was applied. Hence, there is no mechanical deformation observed on grains in the aperture disk, either for radial stress or for rotational stress. Furthermore, the high malleability of copper apparently absorbed stress and strain very well without deforming the grain structure in the surface.

  2. MORPHOLOGICAL CHANGES OF RAT PLACENTA IN DIFFERENT PERIODS OF PREGNANCY UNDER MODELED PREECLAMPSIA.

    PubMed

    Sharashenidze, A; Kikalishvili, L; Turmanidze, T; Sanikidze, T

    2016-04-01

    The purpose of the study was to determine the morphological changes of rat placenta in II, III week of pregnancy under modeled preeclampsia. Modeling of preeclampsia was performed in the rats, as follows: lumen of the abdominal aorta below the renal artery was narrowed by the silk tread on the third of its diameter (0.2 mm). The placenta tissue was studied by histological and immunohistochemical methods (AE1/AE3, CD133, Ki-67). The study has shown that in the experimental model of preeclampsia at the end of II, III week of pregnancy the number of glycogen cells in the placenta trophyspongium layer is reduced compared with the control. There was shown sharp dilatation of the blood sinuses and lacuna, sometimes along the events of stasis. The volume of nucleated erythrocytes in fetal capillaries of the labyrinth layer is reduced compared with the control, especially in IIIweek of pregnancy. In the preparations marked by the CD133 marker, unlike to the norm of III week of pregnancy, the visualization of positive endothelial cells is complicated. The study of the preparations marked by Ki-67 marker reveals that the proliferated activity in the hypoxic placenta tissue is sharply reduced. The exception is those blood tubes, to which umbilical blood vessels are finally formed. It can be concluded that due to hypoxia placenta proliferation of placental blood vessels is disturbed that contributes to the disorder of placental blood circulation, reduce its metabolism in complications of pregnancy. PMID:27249447

  3. Monitoring Morphological Changes in 2D Monolayer Semiconductors Using Atom-Thick Plasmonic Nanocavities

    PubMed Central

    2015-01-01

    Nanometer-sized gaps between plasmonically coupled adjacent metal nanoparticles enclose extremely localized optical fields, which are strongly enhanced. This enables the dynamic investigation of nanoscopic amounts of material in the gap using optical interrogation. Here we use impinging light to directly tune the optical resonances inside the plasmonic nanocavity formed between single gold nanoparticles and a gold surface, filled with only yoctograms of semiconductor. The gold faces are separated by either monolayers of molybdenum disulfide (MoS2) or two-unit-cell thick cadmium selenide (CdSe) nanoplatelets. This extreme confinement produces modes with 100-fold compressed wavelength, which are exquisitely sensitive to morphology. Infrared scattering spectroscopy reveals how such nanoparticle-on-mirror modes directly trace atomic-scale changes in real time. Instabilities observed in the facets are crucial for applications such as heat-assisted magnetic recording that demand long-lifetime nanoscale plasmonic structures, but the spectral sensitivity also allows directly tracking photochemical reactions in these 2-dimensional solids. PMID:25495220

  4. Bovine leukemia virus-induced clinical signs and morphological changes of encephalitozoonosis in rabbits.

    PubMed

    Levkut, M; Lesník, F; Bálent, P; Zajac, V; Korim, P; Sláviková, K

    1997-01-01

    Fourteen three-month-old rabbits spontaneously-infected with the microsporidium Encephalitozoon cuniculi Levaditi, Nicolau et Schoen, 1923 were inoculated intravenously with lymphocytes (Ly) from seropositive bovine leukemia virus infected cattle (Ly/BLV) or with fetal lamb kidney cells infected with bovine fetal leukemia (FLK/BLV). Thirteen rabbits were seropositive to BLV at least for a period of three months. Six rabbits died of pulmonary lesions. Chronic inflammatory lesions of encephalitozoonosis were found in six rabbits killed between 454 and 548 days of the observation period. Five animals bore subcutaneous granulomas. Immunohistochemically, E. cuniculi was demonstrated in the inflammatory lesions of rabbits studied. Control animals also spontaneously infected with E. cuniculi did not show clinical signs of encephalitozoonosis. Morphological changes were found incidentally in the form of small glial foci and focal interstitial nephritis in these animals. The combined action of BLV-E. cuniculi on the bodies of rabbits is proposed as a suitable model for the study of encephalitozoonosis in man with human immunodeficiency virus (HIV) infection. PMID:9437837

  5. Rapid Morphological Change in the Masticatory Structures of an Important Ecosystem Service Provider

    PubMed Central

    Doudna, John W.; Danielson, Brent J.

    2015-01-01

    Humans have altered the biotic and abiotic environmental conditions of most organisms. In some cases, such as intensive agriculture, an organism’s entire ecosystem is converted to novel conditions. Thus, it is striking that some species continue to thrive under such conditions. The prairie deer mouse (Peromyscus maniculatus bairdii) is an example of such an organism, and so we sought to understand what role evolutionary adaptation played in the success of this species, with particular interest in adaptations to novel foods. In order to understand the evolutionary history of this species’ masticatory structures, we examined the maxilla, zygomatic plate, and mandible of historic specimens collected prior to 1910 to specimens collected in 2012 and 2013. We found that mandibles, zygomatic plates, and maxilla have all changed significantly since 1910, and that morphological development has shifted significantly. We present compelling evidence that these differences are due to natural selection as a response to a novel and ubiquitous food source, waste grain (corn, Zea mays and soybean, Glycine max). PMID:26061880

  6. Modulation of morphological changes of microglia and neuroprotection by monocyte chemoattractant protein-1 in experimental glaucoma

    PubMed Central

    Chiu, Kin; Yeung, Sze-Chun; So, Kwok-Fai; Chang, Raymond Chuen-Chung

    2010-01-01

    Monocyte chemoattractant protein-1 (MCP-1)/CCL2 is a C–C chemokine involved in the activation and recruitment of monocytic cells to injury sites. MCP-1/CCL2 can induce either neuroprotection or neurodestruction in vitro, depending on the experimental model. We aim to use MCP-1/CCL2 as an experimental tool to investigate the morphological changes of microglia when loss of healthy retinal ganglion cells (RGCs) is exacerbated or attenuated in an experimental glaucoma model. While a high concentration (1000 ng) of MCP-1/CCL2 and lipopolysaccharide (LPS)-exacerbated RGC loss, 100 ng MCP-1/CCL2 provided neuroprotection towards RGC. Neuroprotective MCP-1/CCL2 (100 ng) also upregulated insulin-like growth factor-1 (IGF-1) immunoreactivity in the RGCs. The neuroprotective effect of MCP-1/CCL2 was not due to the massive infiltration of microglia/macrophages. Taken together, this is the first report showing that an appropriate amount of MCP-1/CCL2 can protect RGCs in experimental glaucoma. PMID:20081877

  7. Rapid Morphological Change in the Masticatory Structures of an Important Ecosystem Service Provider.

    PubMed

    Doudna, John W; Danielson, Brent J

    2015-01-01

    Humans have altered the biotic and abiotic environmental conditions of most organisms. In some cases, such as intensive agriculture, an organism's entire ecosystem is converted to novel conditions. Thus, it is striking that some species continue to thrive under such conditions. The prairie deer mouse (Peromyscus maniculatus bairdii) is an example of such an organism, and so we sought to understand what role evolutionary adaptation played in the success of this species, with particular interest in adaptations to novel foods. In order to understand the evolutionary history of this species' masticatory structures, we examined the maxilla, zygomatic plate, and mandible of historic specimens collected prior to 1910 to specimens collected in 2012 and 2013. We found that mandibles, zygomatic plates, and maxilla have all changed significantly since 1910, and that morphological development has shifted significantly. We present compelling evidence that these differences are due to natural selection as a response to a novel and ubiquitous food source, waste grain (corn, Zea mays and soybean, Glycine max). PMID:26061880

  8. Quantitative evaluation of radiation-induced changes in sperm morphology and chromatin distribution

    SciTech Connect

    Aubele, M.; Juetting, U.R.; Rodenacker, K.; Gais, P.; Burger, G.; Hacker-Klom, U. )

    1990-01-01

    Sperm head cytometry provides a useful assay for the detection of radiation-induced damage in mouse germ cells. Exposure of the gonads to radiation is known to lead to an increase of diploid and higher polyploid sperm and of sperm with head shape abnormalities. In the pilot studies reported here quantitative analysis of the total DNA content, the morphology, and the chromatin distribution of mouse sperm was performed. The goal was to evaluate the discriminative power of features derived by high resolution image cytometry in distinguishing sperm of control and irradiated mice. Our results suggest that besides the induction of the above mentioned variations in DNA content and shape of sperm head, changes of the nonhomogeneous chromatin distribution within the sperm may also be used to quantify the radiation effect on sperm cells. Whereas the chromatin distribution features show larger variations for sperm 21 days after exposure (dpr), the shape parameters seem to be more important to discriminate sperm 35 dpr. This may be explained by differentiation processes, which take place in different stages during mouse spermatogenesis.

  9. [Effects of different contraceptives upon the ovulation changes of the morphological study of the ovaries].

    PubMed

    Bedoya Havia, M; Kesseur, E; Garcia La Madrid, M

    1967-12-01

    Bilateral ovarian wedges were performed on 46 patients scheduled for laparotomies for medical reasons. Prior to the operation, the patients were divided into 5 groups and treated as follows: 1 for control (5 patients); 1 that was given 1 of 3 different combined oral contraceptives, i.e., Anovlar, Gynovlar, or Engynon (22 patients); 1 that was given Sequens (3 patients); 1 that was injected with 200 mg of norethindrone enanthate (14 cases); and 1 given IUDs (2 cases). It was established that all experienced ovulatory cycles prior to therapy. The laparotomies were done between the 22nd-28th day of the menstrual cycle; hormonal therapy was begun between the 3rd-6th day. All but 1 of the group on combined preparations had anovulatory cycles. Detained follicles Grade 3 or 4 with precocious cystic atresic involution were observed. Of the 3 on the sequential preparation, 2 had involuted cystic corpora lutea and 1 had atresic follicles with thecal luteinization. The patients who received the injectable ovulated. There were no morphological or substantial changes in the corpora lutea of the control and IUD groups. PMID:12277382

  10. Cognitive impairment and morphological changes in the dorsal hippocampus of very old female rats.

    PubMed

    Morel, G R; Andersen, T; Pardo, J; Zuccolilli, G O; Cambiaggi, V L; Hereñú, C B; Goya, R G

    2015-09-10

    The hippocampus, a medial temporal lobe structure necessary for the formation of spatial memory, is particularly affected by both normal and pathologic aging. In previous studies, we observed a significant age-related increase in dopaminergic neuron loss in the hypothalamus and the substantia nigra of female rats, which becomes more conspicuous at extreme ages. Here, we extend our studies by assessing spatial memory in 4-6 month-old (young), 26-month-old (old) and 29-32-month-old (senile) Sprague-Dawley female rats as well as the age-related histopathological changes in their dorsal hippocampus. Age changes in spatial memory performance were assessed with a modified version of the Barnes maze test. We employed two probe trials (PTs), one and five days after training, respectively, in order to evaluate learning ability as well as short-term and longer-term spatial memory retention. A set of relevant hippocampal cell markers was also quantitated in the animals by means of an unbiased stereological approach. The results revealed that old rats perform better than senile rats in acquisition trials and young rats perform better than both aging groups. However, during short-term PT both aging groups showed a preserved spatial memory while in longer-term PT, spatial memory showed deterioration in both aged groups. Morphological analysis showed a marked decrease (94-97%) in doublecortin neuron number in the dentate gyrus in both aged groups and a reduction in glial fibrillary acidic protein-positive cell number in the stratum radiatum of aging rats. Astroglial process length and branching complexity decreased in aged rats. We conclude that while target-seeking activity and learning ability decrease in aged females, spatial memory only declines in the longer-term tests. The reduction in neuroblast number and astroglial arborescence complexity in the dorsal hippocampus are likely to play a role in the cognitive deficits of aging rats. PMID:26141841

  11. Recent human impacts and change in dynamics and morphology of ephemeral rivers

    NASA Astrophysics Data System (ADS)

    Ortega, J. A.; Razola, L.; Garzón, G.

    2014-03-01

    Ephemeral streams induce flash-flood events, which cause dramatic morphological changes and impacts on population, mainly because they are intermittent and less predictable. Human pressures on the basin modify load and discharge relationships, inducing dormant instability on the fluvial system that will manifest abruptly during flood events. The flash-flood response of two ephemeral streams affected by load supply modification due to land use changes is discussed in a combination of geomorphic and hydraulic approaches. During the Rivillas flash flood, intensive clearing on the basin led to high rates of sediment flowing into an artificially straightened and inefficient channel. The stream evolved from a sinuous single channel into a shallow braiding occupying the entire width of the valley floor. Misfits and unsteady channel conditions increased velocity, stream power and sediment entrainment capacity and considerably magnified flood damage. Resulting morphosedimentary features revealed a close relationship with the valley floor post-flood hydraulic model, and pre-event awareness would have made it possible to predict risk-sensitive areas. In the second case, the Azohía stream, modelling of current pre-flood channel conditions make it possible to determine channel narrowing and entrenchment in the lower alluvial fan stretch. Abandonment of intensive agriculture, basin reforestation and urbanization diminish load contribution and trigger channel incision. This induces an increase in slope and velocity in the bankfull channel, producing renewed erosive energy and thus activating upstream propagation of incision and bank undermining. The absence of water-spreading dynamics on the alluvial fan in favour of confinement in a single channel produces an unstable dynamic in the system, also offering a false sense of stability, as long as no large magnitude floods occur. When modelling flood-prone areas and analysing hydraulic variables, it is important to detect possible

  12. Ontogenetic change in skull morphology and mechanical advantage in the spotted hyena (Crocuta crocuta).

    PubMed

    Tanner, Jaime B; Zelditch, Miriam L; Lundrigan, Barbara L; Holekamp, Kay E

    2010-03-01

    Weaning represents a challenging transition for young mammals, one particularly difficult for species coping with extreme conditions during feeding. Spotted hyenas (Crocuta crocuta) experience such extreme conditions imposed by intense feeding competition during which the ability to consume large quantities of food quickly is highly advantageous. As adult spotted hyenas have massive skulls specialized for durophagy and can feed very rapidly, young individuals are likely at a competitive disadvantage until that specialized morphology is completely developed. Here we document developmental changes in skull size, shape, and mechanical advantage of the jaws. Sampling an ontogenetic series of Crocuta skulls from individuals ranging in age from 2 months to 18 years, we use linear measurements and geometric morphometrics to test hypotheses suggesting that size, limited mechanical advantage of the jaws, and/or limited attachment sites for jaw muscles might constrain the feeding performance of juveniles. We also examine skull development in relation to key life history events, including weaning and reproductive maturity, to inquire whether ontogeny of the feeding apparatus is slower or more protracted in this species than in carnivores not specialized for durophagy. We find that, although mechanical advantage reaches maturity in hyenas at 22 months, adult skull size is not achieved until 29 months of age, and skull shape does not reach maturity until 35 months. The latter is nearly 2 years after mean weaning age, and more than 1 year after reproductive maturity. Thus, skull development in Crocuta is indeed protracted relative to that in most other carnivores. Based on the skull features that continue to change and to provide additional muscle attachment area, protracted development may be largely due to development of the massive musculature required by durophagy. These findings may ultimately shed light on the adaptive significance of the unusual "role-reversed" pattern of

  13. Morphological approach to scene change detection and digital video storage and retrieval

    NASA Astrophysics Data System (ADS)

    Kim, Woonkyung M.; Song, Samuel M.; Kim, Hyeokman; Song, Cheeyang; Kwon, Byung W.; Kim, Sun G.

    1998-12-01

    With the abstraction of digital video, as the corresponding binary video, a process which, upon subjective experimentation seems to preserve the intelligibility of video content, we can pursue a precise and analytic approach to digital video storage and retrieval algorithm design based upon geometrical and morphological intuition. The foremost and tangible general benefit of such abstraction, however, is the immediate reduction of both data and computational complexities, involved in implementing various algorithms and databases. The general paradigm presented may be utilized to address all issues pertaining to video library construction, including visualization, optimum feedback query generation, and object recognition. However, the primary focus of attention in this paper pertains to detection of fast and gradual scene changes, such as dissolves, fades, and various special effects, such as wipes. Upon simulation, we observed that we can achieve performances comparable to those of others with drastic reductions in both storage and computational complexities. The conversion from grayscale to binary videos can be performed directly (with minimal additional computation) in the compressed domain by thresholding on the DCT DC coefficients themselves, or by using the contour information attached to MPEG4 formats. The algorithms presented herein are ideally suited for performing fast (on-the-fly) determinations of scene change, object recognition, and/or tracking, as well as other, more intelligent, tasks, traditionally requiring heavy demand of computational and/or storage complexities. The fast determinations may then be used on their own merit , or can be used in conjunction/complement with other higher-layer information in the future.

  14. Effects of cadmium metal on young gametophytes of Gelidium floridanum: metabolic and morphological changes.

    PubMed

    Simioni, Carmen; Schmidt, Éder C; Rover, Ticiane; dos Santos, Rodrigo; Filipin, Elisa P; Pereira, Debora T; Costa, Giulia Burle; Oliveira, Eva Regina; Chow, Fungyi; Ramlov, Fernanda; Ouriques, Luciane; Maraschin, Marcelo; Bouzon, Zenilda L

    2015-09-01

    By evaluating carotenoid content, photosynthetic pigments and changes in cellular morphology, growth rates, and photosynthetic performance, this study aimed to determine the effect of cadmium (Cd) on the development of young gametophytes of Gelidium floridanum. Plants were exposed to 7.5 and 15 μM of Cd for 7 days. Control plants showed increased formation of new filamentous thallus, increased growth rates, presence of starch grains in the cortical and subcortical cells, protein content distributed regularly throughout the cell periphery, and intense autofluorescence of chloroplasts. On the other hand, plants treated with Cd at concentrations of 7.5 and 15 μM showed few formations of new thallus with totally depigmented regions, resulting in decreased growth rates. Plants exposed to 7.5 μM Cd demonstrated alterations in the cell wall and an increase in starch grains in the cortical and subcortical cells, while plants exposed to 15 μM Cd showed changes in medullary cells with no organized distribution of protein content. The autofluorescence and structure of chloroplasts decreased, forming a thin layer on the periphery of cells. Cadmium also affected plant metabolism, as visualized by a decrease in photosynthetic pigments, in particular, phycoerythrin and phycocyanin contents, and an increase in carotenoids. This result agrees with decreased photosynthetic performance and chronic photoinhibition observed after treatment with Cd, as measured by the decrease in electron transport rate. Based on these results, it was concluded that exposure to Cd affects cell metabolism and results in significant toxicity to young gametophytes of G. floridanum. PMID:25666304

  15. Cyclophosphamide-Induced Morphological Changes in Dental Root Development of ICR Mice

    PubMed Central

    Kawakami, Tomomi; Nakamura, Yuko; Karibe, Hiroyuki

    2015-01-01

    Background Survivors of childhood cancer are at risk of late dental development. Cyclophosphamide is one of the most commonly used chemotherapeutic agents against cancer in children. The aim of this study was to investigate the effects of cyclophosphamide on root formation in the molars of growing mice and to assess the morphological changes in these roots using three-dimensional structural images. Methods We treated 16 12-day-old ICR mice with cyclophosphamide (100 mg/kg, i.p.) and 16 control mice with saline. At 16, 20, 24, and 27 days of age, the mandibular left first molars were scanned using soft micro-computed tomography. After scanning, the structural indices were calculated using a three-dimensional image analysis system, and the images were subjected to three-dimensional reconstruction. The length and apical foramen area of all distal roots were assessed. Histological changes in the apical region were then assessed via hematoxylin and eosin staining. Results The mandibular molars of all experimental mice showed evidence of cytotoxic injury, which appeared in the form of anomalous root shapes. Although all roots developed further after cyclophosphamide injection, the three-dimensional structural images showed that the roots in the experimental group tended to develop more slowly and were shorter than those in the control group. At 27 days of age, the mean root length was shorter in the experimental group than in the control group. Conversely, the apical foramen of the roots in the experimental group tended to close faster than that of roots in the control group. In addition, hematoxylin and eosin staining of the distal roots in the experimental group showed increased dentin thickness in the apical region. Conclusion Our results suggest that cyclophosphamide can result in short root lengths and early apical foramen closure, eventually leading to V-shaped or thin roots. PMID:26186337

  16. Correlation between Electrophysiological Properties, Morphological Maturation, and Olig Gene Changes during Postnatal Motor Tract Development

    PubMed Central

    Cai, Jun; Zhang, Yi Ping; Shields, Lisa B.E.; Zhang, Zoe Z.; Lui, Naiqui; Xu, Xiao-Ming; Feng, Shi-Qing; Shields, Christopher B.

    2014-01-01

    Background Functional maturation of the nervous system in postnatal (PN) animals is a progressive process that may be assessed using evoked potentials of the auditory, visual, or somatosensory systems. This study investigated electrophysiological and histological changes as well as alterations of myelin relevant proteins of descending motor tracts in rat pups. MEP responses were recorded bi-weekly from postnatal (PN) week-1 to week-9 (adult). Results MEP latencies in PN week-1 rats averaged 23.7 milliseconds and became shorter during early maturation, stabilizing at 6.6 milliseconds at PN week-4. During maturation there was a rapid increase in the conduction velocity (CV). The CV increased from 2.8 ± 0.2 at PN week-1 to 35.2 ± 3.1 mm/ms at PN week-8 which represented functional maturation. Histology of the spinal cord and sciatic nerves revealed progressive axonal myelination. Expression of the oligodendrocyte precursor markers PDGFRα and NG2 were gradually down-regulated in spinal cords, and myelin-relevant proteins such as GalC, CNP, and MBP were increased during maturation. Oligodendrocyte-lineage markers Olig2 and MOG, specifically expressed in myelinated oligodendrocytes, peaked at approximately PN week-3 and were down-regulated thereafter. A similar expression pattern was also observed in neurofilament M/H subunits (NF-M/H). Noticeably, NF-M/H was extensively phosphorylated in adult spinal cords but not in neonatal spinal cords, suggesting an increase in axon diameter and myelin formation. Ultra-structural morphology of axon and myelin sheaths in the ventrolateral funiculus (VLF) showed axon myelination of the VLF axons (99.3%) at PN week-2, while only 44.6% were sheathed at PN week-1. Furthermore, increased axon diameter and myelin thickness in both the VLF and sciatic nerves were highly correlated to the CV (rs>0.95). Conclusions Results from this study indicate that MEPs may be a predicator for the morphological maturity and integrity of myelinated

  17. Morphological changes in glial fibrillary acidic protein immunopositive astrocytes in the hippocampus of dietary-induced obese mice.

    PubMed

    Cano, Victoria; Valladolid-Acebes, Ismael; Hernández-Nuño, Francisco; Merino, Beatriz; Del Olmo, Nuria; Chowen, Julie A; Ruiz-Gayo, Mariano

    2014-06-01

    Long-term consumption of a high-fat diet (HFD) has been shown to trigger both metabolic and cardiovascular diseases. In contrast, the effect of this type of dietary regime on the central nervous system, particularly outside the hypothalamus, has been investigated poorly. Astrocytes, the most abundant population of glial cells in the brain, are pivotal in regulating glutamatergic transmission as they are responsible for most of the glutamate uptake and metabolism. Mice on an HFD show deficits in learning and memory, together with neurochemical and electrophysiological changes compatible with the impairment in hippocampal glutamatergic activity. Because astrocyte function and morphology have been shown to be interdependent, we speculated whether HFD would trigger changes in astrocyte morphology. For this purpose, we have used a model of diet-induced obesity in mice. We have analyzed astrocyte morphology and density by glial fibrillary acidic protein immunohistochemistry, as well as the expression of the glutamate transporters, GLT-1 (glutamate transporter type-1), and GLAST (astrocyte glutamate transporter), in the CA3 area of the hippocampus. We found that astrocytes from HFD mice showed longer and less abundant projections. These changes were accompanied by the upregulation of both GLT-1 and GLAST. Our data show that the functional impairment detected previously in HFD mice is concomitant with morphological changes within the hippocampus. PMID:24911388

  18. Endothelial Cell Morphology and Migration are Altered by Changes in Gravitational Fields

    NASA Technical Reports Server (NTRS)

    Melhado, Caroline; Sanford, Gary; Harris-Hooker, Sandra

    1997-01-01

    Many of the physiological changes of the cardiovascular system during space flight may originate from the dysfunction of basic biological mechanisms caused by microgravity. The weightlessness affects the system when blood and other fluids move to the upper body causing the heart to enlarge to handle the increased blood flow to the upper extremities and decrease circulating volume. Increase arterial pressure triggers baroreceptors which signal the brain to adjust heart rate. Hemodynarnic studies indicate that the microgravity-induced headward fluid redistribution results in various cardiovascular changes such as; alteration of vascular permeability resulting in lipid accumulation in the lumen of the vasculature and degeneration of the the vascular wall, capillary alteration with extensive endothelial invagination. Achieving a true microgravity environment in ground based studies for prolonged periods is virtually impossible. The application of vector-averaged gravity to mammalian cells using horizontal clinostat produces alterations of cellular behavior similar to those observed in microgravity. Similarly, the low shear, horizontally rotating bioreactor (originally designed by NASA) also duplicates several properties of microgravity. Additionally, increasing gravity, i.e., hypcrgravity is easily achieved. Hypergravity has been found to increase the proliferation of several different cell lines (e.g., chick embryo fibroblasts) while decreasing cell motility and slowing liver regeneration following partial hepatectomy. The effect of altered gravity on cells maybe similar to those of other physical forces, i.e. shear stress. Previous studies examining laminar flow and shear stress on endothelial cells found that the cells elongate, orient with the direction of flow, and reorganize their F-actin structure, with concomitant increase in cell stiffness. These studies suggest that alterations in the gravity environment will change the behavior of most cells, including

  19. Morphological Changes within the Rat Lateral Ventricle after the Administration of Proteasome Inhibitors.

    PubMed

    Wójcik, Sławomir; Spodnik, Jan Henryk; Dziewiątkowski, Jerzy; Spodnik, Edyta; Moryś, Janusz

    2015-01-01

    The broad variety of substances that inhibit the action of the ubiquitin-proteasome system (UPS)-known as proteasome inhibitors-have been used extensively in previous studies, and they are currently frequently proposed as a novel form of cancer treatment and as a protective factor in intracerebral hemorrhage treatment. The experimental data on the safest route of proteasome inhibitor administration, their associated side effects, and the possible ways of minimizing these effects have recently become a very important topic. The aim of our present study was to determine the effects of administering of MG-132, lactacystin and epoxomicin, compounds belonging to three different classes of proteasome inhibitors, on the ependymal walls of the lateral ventricle. Observations were made 2 and 8 weeks after the intraventricular administration of the studied substances dissolved in dimethyl sulfoxide (DMSO) into the lateral ventricle of adult Wistar rats. Qualitative and quantitative analysis of brain sections stained with histochemical and inmmunofluorescence techniques showed that the administration of proteasome inhibitors caused a partial occlusion of the injected ventricle in all of the studied animals. The occlusion was due to ependymal cells damage and subsequent ependymal discontinuity, which caused direct contact between the striatum and the lateral nuclei of the septum, mononuclear cell infiltration and the formation of a glial scar between these structures (with the activation of astroglia, microglia and oligodendroglia). Morphologically, the ubiquitin-positive aggregates corresponded to aggresomes, indicating impaired activity of the UPS and the accumulation and aggregation of ubiquitinated proteins that coincided with the occurrence of glial scars. The most significant changes were observed in the wall covering the striatum in animals that were administered epoxomicin, and milder changes were observed in animals administered lactacystin and MG-132. Interestingly

  20. Processes driving rapid morphological changes observed on the Khumbu Glacier, Nepal

    NASA Astrophysics Data System (ADS)

    Quincey, Duncan; Rowan, Ann; Gibson, Morgan; Irvine-Fynn, Tristram; King, Owen; Watson, Scott

    2016-04-01

    The response of many Himalayan glaciers to climatic change is complicated by the presence of a supraglacial debris cover, which leads to a suite of processes controlling mass loss that are not commonly found where glaciers are debris-free. Here, we present a range of field, surface topographic and ice-dynamical observations acquired from Khumbu Glacier in Nepal, to describe and quantify these processes in fine spatial and temporal resolution. Like many other debris-covered glaciers in the Himalaya, the debris-covered tongue of the Khumbu Glacier is heavily in recession. For at least two decades, the lower ablation area has been stagnant as surface lowering in the mid-ablation zone has led to ever decreasing driving stresses. Contemporary velocity data derived from TerraSAR-X imagery confirms that the active-inactive ice boundary can now be found 5 km from the glacier terminus and that the maximum velocity, immediately below the icefall, is around 70 m per year. These data show that in this upper part of the ablation zone, the glacier velocity has not changed during the last 20 years, suggesting that at least above the icefall the glacier remains healthy. Across the stagnant debris-covered tongue there have been marked surface morphological changes. Mapping from 2004 shows relatively few surface ponds, a homogeneous debris-covered surface, and a small area towards the terminus supporting soil formation and low vegetation. Mapping from field observations in 2014 shows an abundance of surface meltwater, a more heterogeneous surface texture associated with many exposed ice cliffs, and a long (3 km) zone of stable terrain where soils are developing and, in places, low scrub can be found. Most dramatically, a string of surface ponds occupying the true-left lowermost 2 km of ice have expanded and coalesced, suggesting the glacier has crossed a threshold leading towards large glacial lake development. Two fine-resolution DEMs derived from Structure-from-Motion in spring

  1. Natural and anthropogenic change in the morphology and connectivity of tidal channels of southwest Bangladesh

    NASA Astrophysics Data System (ADS)

    Wilson, C.; Goodbred, S. L., Jr.; Wallace Auerbach, L.; Ahmed, K. R.; Small, C.; Sams, S. E.

    2014-12-01

    Over the last century, land use changes in the Ganges-Brahmaputra tidal delta have transformed >5000 km2 of intertidal mangrove forest to densely inhabited, agricultural islands that have been embanked to protect against tides and storm surges (i.e., polders). More recently, the conversion of rice paddies to profitable shrimp aquaculture has become increasingly widespread. Recent field studies documented that poldering in southwest Bangladesh has resulted in an elevation deficit relative to that of the natural mangrove forests and mean high water (MHW). The offset is a function of lost sedimentation, enhanced compaction, and an effective rise in MHW from tidal amplification. The morphologic adjustment of the tidal channel network to these perturbations, however, has gone largely undocumented. One effect has been the shoaling of many channels due to decreases in fluvial discharge and tidal prism. We document a previously unrecognized anthropogenic component: the widespread closure of large conduit tidal channels for land reclamation and shrimp farming. GIS analysis of historical Landsat and Google Earth imagery within six 1000 km2 study areas reveals that the tidal network in the natural Sundarbans mangrove forest has remained relatively constant since the 1970s, while significant changes are observed in human-modified areas. Construction of the original embankments removed >1000 km of primary tidal creeks, and >80 km2 of land has been reclaimed outside of polders through the closure of formerly active tidal channels (decrease in mean channel width from 256±91 m to 25±10 m). Tidal restriction by large sluice gates is prevalent, favoring local channel siltation. Furthermore, severing the intertidal platform and large conduit channels from the tidal network has had serious repercussions, such as increased lateral migration and straightening of the remaining channels. Where banklines have eroded, the adjacent embankments appear to be more vulnerable to failure, as

  2. Phytohormonal Regulation of Biomass Allocation and Morphological and Physiological Traits of Leaves in Response to Environmental Changes in Polygonum cuspidatum

    PubMed Central

    Sugiura, Daisuke; Kojima, Mikiko; Sakakibara, Hitoshi

    2016-01-01

    Plants plastically change their morphological and physiological traits in response to environmental changes, which are accompanied by changes in endogenous levels of phytohormones. Although roles of phytohormones in various aspects of plant growth and development were elucidated, their importance in the regulation of biomass allocation was not fully investigated. This study aimed to determine causal relationships among changes in biomass allocation, morphological and physiological traits, and endogenous levels of phytohormones such as gibberellins (GAs) and cytokinins (CKs) in response to environmental changes in Polygonum cuspidatum. Seedlings of P. cuspidatum were grown under two light intensities, each at three nitrogen availabilities. The seedlings grown in high light intensity and high nitrogen availability (HH) were subjected to three additional treatments: Defoliating half of the leaves (Def), transferral to low nitrogen availability (LowN), or low light intensity (LowL). Biomass allocation at the whole-plant level, morphological and physiological traits of each leaf, and endogenous levels of phytohormones in each leaf and shoot apex were measured. Age-dependent changes in leaf traits were also investigated. After the treatments, endogenous levels of GAs in the shoot apex and leaves significantly increased in Def, decreased in LowN, and did not change in LowL compared with HH seedlings. Among all of the seedlings, the levels of GAs in the shoot apex and leaves were strongly correlated with biomass allocation ratio between leaves and roots. The levels of GAs in the youngest leaves were highest, while the levels of CKs were almost consistent in each leaf. The levels of CKs were positively correlated with leaf nitrogen content in each leaf, whereas the levels of GAs were negatively correlated with the total non-structural carbohydrate content in each leaf. These results support our hypothesis that GAs and CKs are key regulatory factors that control biomass

  3. Phytohormonal Regulation of Biomass Allocation and Morphological and Physiological Traits of Leaves in Response to Environmental Changes in Polygonum cuspidatum.

    PubMed

    Sugiura, Daisuke; Kojima, Mikiko; Sakakibara, Hitoshi

    2016-01-01

    Plants plastically change their morphological and physiological traits in response to environmental changes, which are accompanied by changes in endogenous levels of phytohormones. Although roles of phytohormones in various aspects of plant growth and development were elucidated, their importance in the regulation of biomass allocation was not fully investigated. This study aimed to determine causal relationships among changes in biomass allocation, morphological and physiological traits, and endogenous levels of phytohormones such as gibberellins (GAs) and cytokinins (CKs) in response to environmental changes in Polygonum cuspidatum. Seedlings of P. cuspidatum were grown under two light intensities, each at three nitrogen availabilities. The seedlings grown in high light intensity and high nitrogen availability (HH) were subjected to three additional treatments: Defoliating half of the leaves (Def), transferral to low nitrogen availability (LowN), or low light intensity (LowL). Biomass allocation at the whole-plant level, morphological and physiological traits of each leaf, and endogenous levels of phytohormones in each leaf and shoot apex were measured. Age-dependent changes in leaf traits were also investigated. After the treatments, endogenous levels of GAs in the shoot apex and leaves significantly increased in Def, decreased in LowN, and did not change in LowL compared with HH seedlings. Among all of the seedlings, the levels of GAs in the shoot apex and leaves were strongly correlated with biomass allocation ratio between leaves and roots. The levels of GAs in the youngest leaves were highest, while the levels of CKs were almost consistent in each leaf. The levels of CKs were positively correlated with leaf nitrogen content in each leaf, whereas the levels of GAs were negatively correlated with the total non-structural carbohydrate content in each leaf. These results support our hypothesis that GAs and CKs are key regulatory factors that control biomass

  4. Transmural progression of morphologic changes during ischemic contracture and reperfusion in the normal and hypertrophied rat heart.

    PubMed Central

    Anderson, P. G.; Bishop, S. P.; Digerness, S. B.

    1987-01-01

    The purpose of this study was to compare the functional and morphologic changes that occur during ischemic contracture and reperfusion in the normal and hypertrophied heart. Hearts from Sprague-Dawley, spontaneously hypertensive (SHR), and normotensive Wistar-Kyoto rats were evaluated using a modified Langendorff perfusion apparatus. After obtaining control data, hearts were potassium-arrested, made ischemic, and studied at various time points. Regional coronary flow was assessed with the use of radiolabeled microspheres or Microfil dye infusion, and morphologic changes were evaluated by means of light and electron microscopy. Sarcomere length changes and qualitative morphologic changes during global ischemia demonstrate a transmural progression of ischemic damage starting at the endocardium and extending, with time, epicardially. The progression of ischemic changes in hypertrophied hearts of SHRs was similar to that of normal hearts; however, hypertrophied hearts developed ischemic contracture sooner than normal hearts. In addition, the development of contraction band change after ischemic contracture occurred only when hearts were reperfused and was related to the development of no-reflow. Images Figure 4 Figure 5 Figure 2 Figure 3 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 PMID:2959155

  5. Exploring topographic methods for monitoring morphological changes in mountain channels of different size and slope

    NASA Astrophysics Data System (ADS)

    Theule, Joshua; Bertoldi, Gabriele; Comiti, Francesco; Macconi, Pierpaolo; Mazzorana, Bruno

    2015-04-01

    High resolution digital elevation models (DEM) can easily be obtained using either laser scanning technology or photogrammetry with structure from motion (SFM). The scale, resolution, and accuracy can vary according to how the data is acquired, such as by helicopter, drone, or extendable pole. In the Autonomous Province of Bozen-Bolzano (Northern Italy), we had the opportunity to compare several of these techniques at different scales in mountain streams ranging from low-gradient braided rivers to steep debris flow channels. The main objective is to develop protocols for efficient monitoring of morphologic changes in different parts of the river systems. For SFM methods, we used the software "Photoscan Professional" (Agisoft) to generate densified point clouds. Both artificial and natural targets were used to georeference them. In some cases, targets were not even necessary and point clouds could be aligned with older point clouds by using the iterative closest point algorithm in the freeware "CloudCompare". At the Mareit/Mareta River, a restored braided river, an airborne laser scan survey (2011) was compared to a SFM DEM derived from a helicopter photo survey (2014) carried out (by the Autonomous Province of Bolzano) at approximately 100 m above ground. Photogrammetry point clouds had an alignment error of 1.5 cm and had three times more data coverage than laser scanning. Indeed, the large spacing and clustering of 2011 ALS swaths led to areas of no data when a 10-cm grid is developed. In the Gadria basin, a debris flow monitoring catchment, we used a sediment retention basin to compare debris flow volumes resulting from i) a drone (by the "Mavtech" company) survey at 10 m above ground (with GoPro camera), ii) a 5-m pole-mounted camera (with Canon EOS 700D) and iii) a 3-m pole-mounted camera (with GoPro Hero Silver3+) to a iv) TLS survey. As the drone had limited load capacity (especially at high elevations) we used the lightweight GoPro Hero 3+, but due to the

  6. Linking Surface Morphological Change to Subsurface Fluvial Architecture: What Imprints do big Floods Leave?

    NASA Astrophysics Data System (ADS)

    Ashworth, P. J.; Best, J. L.; Sambrook-Smith, G. H.; Parker, N.; Lane, S. N.; Lunt, I. A.; Simpson, C. J.; Widdison, P. E.

    2008-12-01

    Ideas concerning the origin of alluvial deposits and their paleoenvironmental interpretation have usually resulted in two schools of thought: that such deposits are either the result of ordinary 'day-to-day' processes that acted uniformly through time, or that they are related to rare events that had a disproportionate effect on erosion and deposition rates. Despite the long running debate of gradualism and catastrophism within the Earth Sciences, there is surprisingly little quantitative data to assess what magnitude of event is represented in many fluvial sequences. This paper reports results of a unique natural 'experiment' where surface (digital elevation models obtained from digital photogrammetry) and subsurface (ground penetrating radar, GPR) data were taken immediately prior to, and after, a large (1 in 40 year) flood event that occurred in 2005 on the sand-bed, braided South Saskatchewan River, Canada. We surveyed several reaches of the river both before and after this major flood event, and collected repeat aerial surveys of the entire channel, as well as GPR surveys along identical survey lines. This allows us to examine the morphological change in the channel form during this flood, quantify the probability distributions of bed heights within the channels, and assess the amount of erosion and/or deposition represented within the subsurface architecture. Results indicate that although this high-magnitude flood had a marked geomorphic impact, the style and scale of both scour and deposition were the same as that measured during lower-magnitude, annual, floods. Hence, rather than being a reflection of either frequent or rare events, alluvial deposits in the South Saskatchewan contain the record of both but these different scale events may be virtually indistinguishable in the subsurface alluvial architecture.

  7. Diabetes-induced changes in the morphology and nociceptinergic innervation of the rat uterus.

    PubMed

    Tariq, Saeed; Nurulain, Syed M; Rashed, Hameed; Lotfy, Mohamed; Emerald, Starling Bright; Koturan, Surya; Tekes, Kornélia; Adeghate, Ernest

    2016-02-01

    The prevalence of diabetes mellitus (DM) is about 6% across the globe. This prevalence has been reported to increase in the near future. This means that the number of women with DM who would like to get pregnant and have children will also increase. The present study is aimed at investigating the morphological changes observed in the uterus after the onset of DM. The study also examined the pattern of distribution of nociceptin (NC), a neuropeptide involved in the regulation of pain, a major physiological factor during parturition. The study shows a severe atrophy of uteri as early as 15 days post DM and continued until the termination of the eight-week study. This atrophy was confirmed by light microscopy. Electron microscopy study showed atrophy of the columnar cells of the endometrium, reduced myofibril number and destruction of smooth muscle cells in the myometrium of diabetic rats compared to control. Immunofluorescence and immunoelectron microscopy studies clearly demonstrated the presence of NC in the endometrium, myometrium and on the myofibrils of the smooth muscles of both control and diabetic rat uteri. In addition, NC-positive neurons and varicose fibres were observed in the myometrium of both normal and diabetic rats. However, the expression of NC decreased after the onset of DM. Morphometric analysis showed that the number of NC-labeled cells was significantly (p < 0.05) lower in diabetic rat uteri compared to those of control. In conclusion, DM-induced uterine atrophy is associated with a decrease in the expression of NC in cells, neurons and myofibrils of the rat uterus. PMID:26589323

  8. Escherichia coli Morphological Changes and Lipid A Removal Induced by Reduced Pressure Nitrogen Afterglow Exposure

    PubMed Central

    Zerrouki, Hayat; Rizzati, Virginie; Bernis, Corinne; Nègre-Salvayre, Anne; Sarrette, Jean Philippe; Cousty, Sarah

    2015-01-01

    Lipid A is a major hydrophobic component of lipopolysaccharides (endotoxin) present in the membrane of most Gram-negative bacteria, and the major responsible for the bioactivity and toxicity of the endotoxin. Previous studies have demonstrated that the late afterglow region of flowing post-discharges at reduced pressure (1-20 Torr) can be used for the sterilization of surfaces and of the reusable medical instrumentation. In the present paper, we show that the antibacterial activity of a pure nitrogen afterglow can essentially be attributed to the large concentrations of nitrogen atoms present in the treatment area and not to the UV radiation of the afterglow. In parallel, the time variation of the inactivation efficiency quantified by the log reduction of the initial Escherichia coli (E. coli) population is correlated with morphologic changes observed on the bacteria by scanning electron microscopy (SEM) for increasing afterglow exposure times. The effect of the afterglow exposure is also studied on pure lipid A and on lipid A extracted from exposed E. coli bacteria. We report that more than 60% of lipid A (pure or bacteria-extracted) are lost with the used operating conditions (nitrogen flow QN2 = 1 standard liter per minute (slpm), pressure p = 5 Torr, microwave injected power PMW = 200 W, exposure time: 40 minutes). The afterglow exposure also results in a reduction of the lipid A proinflammatory activity, assessed by the net decrease of the redox-sensitive NFκB transcription factor nuclear translocation in murine aortic endothelial cells stimulated with control vs afterglow-treated (pure and extracted) lipid A. Altogether these results point out the ability of reduced pressure nitrogen afterglows to neutralize the cytotoxic components in Gram-negative bacteria. PMID:25837580

  9. Morphological, biochemical, molecular and ultrastructural changes induced by Cd toxicity in seedlings of Theobroma cacao L.

    PubMed

    Castro, Andressa V; de Almeida, Alex-Alan F; Pirovani, Carlos P; Reis, Graciele S M; Almeida, Nicolle M; Mangabeira, Pedro A O

    2015-05-01

    Seeds from Theobroma cacao progenies derived from the self-pollination of 'Catongo'×'Catongo' and the crossing between CCN-10×SCA-6 were immersed for 24h in different Cd solutions (2; 4; 8; 16 and 32 mgL(-1)) along with the control treatment (without Cd). Shortly after, the seeds were sown in plastic tubes containing organic substrate and were grown in a greenhouse for 60 days. The treatment with Cd was observed to cause morphological, biochemical, molecular and ultrastructural changes in both progenies of T. cacao. There has been deformation in chloroplasts, nuclear chromatin condensation, and reduction in thickness of the mesophyll. As for 'Catongo'×'Catongo', a decrease in thickness of the epidermis was noted on the abaxial face. There has been increased guaiacol peroxidase activity in the roots of CCN-10×SCA-6, as well as in the''Catongo'×'Catongo' leaves. In the presence of Cd, CCN-10×SCA-6 showed increased expression of the genes associated with the biosynthesis of phytochelatin (PCS-1) and class III peroxidases (PER-1) in leaves, and metallothionein (MT2b), in roots. In 'Catongo'×'Catongo', there has been an increase in the expression of genes associated with the biosynthesis of PER-1 and cytosolic superoxide dismutase dependent on copper and zinc (Cu-Zn SODCyt) in leaves and from MT2b and PCS-1 and roots. There was higher accumulation of Cd in the aerial parts of seedlings from both progenies, whereas the most pronounced accumulation was seen in''Catongo'×'Catongo'. The increase in Cd concentration has led to lower Zn and Fe levels in both progenies. Hence, one may conclude that the different survival strategies used by CCN-10×SCA-6 made such progeny more tolerant to Cd stress when compared to''Catongo'×'Catongo'. PMID:25700096

  10. Changes in lung morphology and cell number in radiation pneumonitis and fibrosis: a quantitative ultrastructural study

    SciTech Connect

    Vergara, J.A.; Raymond, U.; Thet, L.A.

    1987-05-01

    We used stereologic-morphometric techniques to obtain a detailed quantitative picture of the changes in lung ultrastructure of rats at 12 and 26 weeks after unilateral thoracic irradiation with 3000 cGy. At 12 weeks post-radiation, the total number type 1 epithelial cells, type 2 epithelial cells and capillary endothelial cells were decreased 50-70%, total type 1 epithelial and capillary surface areas were decreased 55-60%, and the total volume of intracapillary blood was decreased 75%. The interstitial cells and matrix together accounted for more than 9% of the peripheral lung tissue volume including air, compared to 3% in controls. The numerical density of interstitial cells was increased to 3-fold the control value. The numerical density of interstitial cells was increased to 3-fold the control value. Although fibroblasts still comprised the largest interstitial cell subgroup, the numerical density of mast cells was increased over 150-fold and other inflammatory and immune cells were increased to a lesser extent. At 26 weeks post-radiation, the number, volume, and surface area of the type 1 epithelium and capillary endothelium had further decreased to only 5-10% of control values. The total number of type 2 epithelial cells was reduced by 75% but the volume density was actually increased because of a 4-fold increase in the mean cell volume. The interstitial cells and matrix now comprised over 77% of total peripheral lung tissue volume including air as compared to 6% in controls. Mast cells and plasma cells comprised 11% and 19% of all interstitial cells respectively and the densities of these cells were 540 and 180-fold the control value respectively. The relation of these morphometric findings to the results of previous morphologic studies is discussed.

  11. Morphologic change of rectosigmoid colon using belly board and distended bladder protocol

    PubMed Central

    Cho, Yeona; Chang, Jee Suk; Kim, Mi Sun; Lee, Jaehwan; Byun, Hwakyung; Kim, Nalee; Park, Sang Joon; Keum, Ki Chnag

    2015-01-01

    Purpose This study investigates morphologic change of the rectosigmoid colon using a belly board in prone position and distended bladder in patients with rectal cancer. We evaluate the possibility of excluding the proximal margin of anastomosis from the radiation field by straightening the rectosigmoid colon. Materials and Methods Nineteen patients who received preoperative radiotherapy between 2006 and 2009 underwent simulation in a prone position (group A). These patients were compared to 19 patients treated using a belly board in prone position and a distended bladder protocol (group B). Rectosigmoid colon in the pelvic cavity was delineated on planning computed tomography (CT) images. A total dose of 45 Gy was planned for the whole pelvic field with superior margin of the sacral promontory. The volume and redundancy of rectosigmoid colon was assessed. Results Patients in group B had straighter rectosigmoid colons than those in group A (no redundancy; group A vs. group B, 10% vs. 42%; p = 0.03). The volume of rectosigmoid colon in the radiation field was significantly larger in group A (56.7 vs. 49.1 mL; p = 0.009). In dose volume histogram analysis, the mean irradiated volume was lower in patients in group B (V45 27.2 vs. 18.2 mL; p = 0.004). In Pearson correlation coefficient analysis, the in-field volume of rectosigmoid colon was significantly correlated with the bladder volume (R = 0.86, p = 0.003). Conclusion Use of a belly board and distended bladder protocol could contribute to exclusion of the proximal margin of anastomosis from the radiation field. PMID:26157683

  12. Morphological change of self-organized protrusions of fluoropolymer surface by ion beam irradiation

    NASA Astrophysics Data System (ADS)

    Kitamura (Ogawa), Akane; Kobayashi, Tomohiro; Satoh, Takahiro; Koka, Masashi; Kamiya, Tomihiro; Suzuki, Akihiro; Terai, Takayuki

    2013-07-01

    Polytetrafluoroethylene (PTFE) and fluorinated ethylene propylene (FEP) are typical fluoropolymers displaying several desirable technological properties such as electrical insulation and high chemical resistance. When their surfaces are irradiated with ion beams, dense micro-protrusions formed after the emergence and spread of micropores across the entire irradiated area, allowing culture cells to spread on the top of the protrusions. In this study, we investigate the morphological changes introduced in the fluoropolymer surfaces by ion beams as the energy of the beams is increased. When an FEP sample was irradiated with a nitrogen ion beam with an energy of less than 350 keV at 1.0 μA/cm2, protrusions were formed with a density between 2 × 107/cm2 and 2 × 108/cm2. However, at energies higher than 350 keV, the protrusions became sparse, and the density dropped to 5 × 102/cm2. Protrusions appeared sporadically during irradiation at high energies, and the top of the protrusions appeared as spots inside the sample, which were difficult to etch and became elongated as the erosion of the surface progressed. Erosion was caused by sputtering of FEP molecules and evaporation at notably elevated temperatures on the surface. Analysis based on attenuated total reflectance/Fourier transform infrared spectroscopy showed the presence of Cdbnd C bonds as well as -COOH, -Cdbnd O, and -OH bonds on all irradiated samples. Their concentration on the surface densely covered with micro-protrusions was higher than that on the surface with sparse protrusions after irradiation at energies exceeding 350 keV. Thus, we determined a suitable range for the ion energy for creating FEP surfaces densely covered with protrusions.

  13. Polyglycolide: degradation and drug release. Part I: changes in morphology during degradation.

    PubMed

    Hurrell, S; Cameron, R E

    2001-09-01

    The changing morphology of quenched polyglycolide (PGA) is investigated during hydrolytic degradation in phosphate buffered saline at pH 7.4. Analysis techniques include small and wide-angle X-ray scattering (SAXS and WAXS), mass measurements, DSC, pH measurement and UV-spectrophotometry. It is postulated that the degradation process can be separated into four distinct stages. In stage I, water diffuses quickly into the sample. During stage II, the polymer crystallizes by insertion crystallization, whilst the molecular weight gradually falls. This stage is characterized by a dramatic fall in the long period together with an increase in the crystallinity, minimal mass loss and minimal water uptake. At the onset of stage III, at around 10 days, a critical molecular weight is reached. Degradation products are now small enough to diffuse from the surface of the sample which begins to swell, water diffuses into the space created, and the crystals are freed from constraint. A co-operation between degradation products diffusing out of the sample and the water diffusing in causes "reaction-erosion" fronts to develop inside the sample. Ahead of these fronts, the trapped acidic degradation products remain to catalyze the hydrolysis. Stage III is characterized by swelling and an increase in the long period, together with mass loss and further water uptake. It is postulated that these reaction-erosion fronts move through the sample and meet in the centre at the beginning of stage IV, at which point the degradation again becomes homogeneous throughout the sample. PMID:15348229

  14. Chemical and morphological changes in archaeological seeds and fruits during preservation by desiccation

    NASA Astrophysics Data System (ADS)

    Van Bergen, P. F.; Bland, H. A.; Horton, M. C.; Evershed, R. P.

    1997-05-01

    Soluble and insoluble constituents of modern and ancient (ca. 600 AD) desiccated barley kernels and radish seeds have been studied using high-temperature gas chromatography-mass spectrometry, scanning electron microscopy, and Curie-point pyrolysis-gas chromatography-mass spectrometry. Although some changes in colour are seen, the morphology and anatomy of the desiccated specimens are largely unchanged compared with their extant counterparts. The main chemical alterations arising through long-term desiccation are chemically rather than microbially mediated. Comparison between the lipid data from the modern and ancient barley and radish reveals that extensive ester hydrolysis has occurred over time, while oxidation has been retarded. The insoluble material of the modern barley kernel walls, which is composed of a lignin-cellulose complex characteristic of monocotyledons, undergoes upon desiccation chemical alterations resulting in a significant decrease in the abundance of polysaccharides and cinnamic acids moieties. In marked contrast, the insoluble constituents of the modern radish seed coat yields primarily amino acid moieties upon pyrolysis, most likely deriving from proteins. The seed coal also contains a polyphenolic macromolecule and a small contribution from a dicotyledon lignincellulose complex. This is the first time such a distinct chemical composition has been reported for modern sclerotic plant tissues. The chemical composition of the tissues of the ancient radish specimens appears little altered compared with their modern counterparts; the only obvious difference is the decrease in abundance of 2,6-dimethoxyphenol moieties in the lignin-cellulose pyrolysis products. Comparison of the microscopic and chemical data with that of walls of propagules, i.e., fruits and seeds, deposited in aquatic environments reveals no differences between the material deposited under desiccating and aquatic conditions.

  15. Escherichia coli morphological changes and lipid A removal induced by reduced pressure nitrogen afterglow exposure.

    PubMed

    Zerrouki, Hayat; Rizzati, Virginie; Bernis, Corinne; Nègre-Salvayre, Anne; Sarrette, Jean Philippe; Cousty, Sarah

    2015-01-01

    Lipid A is a major hydrophobic component of lipopolysaccharides (endotoxin) present in the membrane of most Gram-negative bacteria, and the major responsible for the bioactivity and toxicity of the endotoxin. Previous studies have demonstrated that the late afterglow region of flowing post-discharges at reduced pressure (1-20 Torr) can be used for the sterilization of surfaces and of the reusable medical instrumentation. In the present paper, we show that the antibacterial activity of a pure nitrogen afterglow can essentially be attributed to the large concentrations of nitrogen atoms present in the treatment area and not to the UV radiation of the afterglow. In parallel, the time variation of the inactivation efficiency quantified by the log reduction of the initial Escherichia coli (E. coli) population is correlated with morphologic changes observed on the bacteria by scanning electron microscopy (SEM) for increasing afterglow exposure times. The effect of the afterglow exposure is also studied on pure lipid A and on lipid A extracted from exposed E. coli bacteria. We report that more than 60% of lipid A (pure or bacteria-extracted) are lost with the used operating conditions (nitrogen flow QN2 = 1 standard liter per minute (slpm), pressure p = 5 Torr, microwave injected power PMW = 200 W, exposure time: 40 minutes). The afterglow exposure also results in a reduction of the lipid A proinflammatory activity, assessed by the net decrease of the redox-sensitive NFκB transcription factor nuclear translocation in murine aortic endothelial cells stimulated with control vs afterglow-treated (pure and extracted) lipid A. Altogether these results point out the ability of reduced pressure nitrogen afterglows to neutralize the cytotoxic components in Gram-negative bacteria. PMID:25837580

  16. Normal sperm morphology and changes of semen characteristics and abnormal morphological spermatozoa among peri-mating seasons in captive japanese black bears (Ursus thibetanus japonicus).

    PubMed

    Okano, Tsukasa; Murase, Tetsuma; Nakamura, Sachiko; Komatsu, Takeshi; Tsubota, Toshio; Asano, Makoto

    2009-04-01

    The objectives of this study were to obtain morphological data for normal spermatozoa and to investigate seasonal changes (the early, mid- and post-mating seasons) in abnormal morphology of spermatozoa and the characteristics of semen in Japanese black bears. Semen was collected by electroejaculation from 34 captive male Japanese black bears a total of 74 times. Length of head, width of head, length of midpiece and total length of the spermatozoa were 6.3 +/- 0.4, 4.5 +/- 0.3, 10.4 +/- 0.7 and 69.6 +/- 3.1 mum (mean +/- SD; 20 semen, 200 spermatozoa), respectively. In the semen collected during the mid-mating season, ejaculate volume, ejaculate pH, sperm concentration, total sperm count, motility, viability and intact acrosomes were 0.46 +/- 0.36 ml, 7.3 +/- 0.4, 659 +/- 644 x 10(6)/ml, 214 +/- 208 x 10(6), 82.9 +/- 9.6%, 89.3 +/- 9.5% and 97.0 +/- 3.2% (mean +/- SD; n=21, in ejaculate pH n=8), respectively. Sperm motility and viability in the early (n=7) and mid-mating (n=21) seasons were significantly higher than in the post-mating (n=8) season. The rates of detached heads in the early and mid-mating season were significantly lower than in the post-mating season. The main abnormal morphologies observed (mean +/- SD%; n=23) were simply bent tail (19.9 +/- 22.6), distal droplets (13.5 +/- 11.7), proximal droplets (9.6 +/- 7.8), teratoid spermatozoa (6.7 +/- 10.7), knobbed acrosome (4.9 +/- 8.6), acrosome damage (3.7 +/- 2.8) and bent midpiece (3.7 +/- 5.1). The data will be useful for artificial breeding and further research on male reproductive physiology in this species. PMID:19194064

  17. Quantifying Morphologic Changes in a Low Gradient River Crossing Southeast Louisiana Fault Zones

    NASA Astrophysics Data System (ADS)

    Fischer, G.; Gasparini, N. M.; Dawers, N. H.

    2011-12-01

    This study investigates the signature of faulting in low gradient, alluvial rivers crossing the Baton Rouge fault zone (BRFZ) and Denham Springs-Scotlandville fault zone (DSSFZ), which encompass a set of East-West striking normal faults in southeast Louisiana. These faults exhibit surface expressions associated with up to a few meters of vertical displacement of Late Pleistocene sediments, but little is known about their activity during the Holocene. Our study aims to quantify geomorphic changes in a number of rivers that cross these fault zones and to use these changes to gain insight into the history of faulting in the region. We hypothesize that fault movement will be evident in patterns of river sinuosity, slope, and width to depth ratio. We focus on four subparallel channels of various discharges that cross either or both the BRFZ and the DSSFZ. Information on local fault scarp heights and channel reaches are extracted by GIS analysis of the LA LiDAR 5 m DEM, as well as flow modeling using the HEC-RAS software program. On the Tickfaw River, we conducted field surveys using differential GPS to record contemporary water surface slopes and channel location. Historic channel features on the Tickfaw are characterized using a series of aerial photographs dating back to 1952. Over the past 50 years, the Tickfaw River has shortened its course through the study area significantly (~4.9%) by means of meander cutoffs. Since 1952, sinuosity (P) has decreased in all of the Tickfaw channel reaches that cross fault segments. Currently, the sinuosity is extremely low (average P = 1.14) where the river crosses the DSSFZ and slightly higher where the river crosses the BRFZ (average P = 1.9). We use the LiDAR data to quantify offset on the faults that the river crosses. These values will be compared with the average lateral migration rate of the river in order to better understand the time scales over which both processes operate. If the faults appear to have little morphologic

  18. Developmental changes in the facial morphology of the Borneo orangutan (Pongo pygmaeus): possible signals in visual communication.

    PubMed

    Kuze, Noko; Malim, Titol Peter; Kohshima, Shiro

    2005-04-01

    Orangutans display remarkable developmental changes and sexual differences in facial morphology, such as the flanges or cheek-pads that develop only on the face of dominant adult males. These changes suggest that facial morphology is an important factor in visual communication. However, developmental changes in facial morphology have not been examined in detail. We studied developmental changes in the facial morphology of the Borneo orangutan (Pongo pygmaeus) by observing 79 individuals of various ages living in the Sepilok Orangutan Rehabilitation Centre (SORC) in Malaysia and in Japanese zoos. We also analyzed photographs of one captive male that were taken over a period of more than 16 years. There were clear morphological changes that occurred with growth, and we identified previously unreported sexual and developmental differences in facial morphology. Light-colored skin around the eyes and mouth is most prominent in animals younger than 3 years, and rapidly decreases in area through the age of approximately 7 years. At the same time, the scattered, erect hairs on the head (infant hair) become thick, dense hairs lying on the head (adult hair) in both sexes. The results suggest that these features are infant signals, and that adult signals may include darkened face color, adult hair, whiskers, and a beard, which begin to develop after the age of approximately 7 years in both sexes. In females, the eyelids remain white even after 10 years, and turn black at around the age of 20; in males, the eyelids turn black before the age of 10. The whiskers and beards of adults are thicker in males than in females, and are fully developed before the age of 10 in males, while they begin to develop in females only after approximately 20 years. White eyelids and undeveloped whiskers and beards may be visual signals that are indicative of young adult females. Our results also show that the facial morphology of the unflanged male is similar to that of the adult female, although

  19. Changes to the morphology, structure and properties as a consequence of polyethylene working in a polymer-metal kinematic pair

    SciTech Connect

    Maszybrocka, Joanna; Cybo, Jerzy; Cwajna, Jan

    2009-10-15

    A change is presented of the orientation of lamellar structure, degree of crystallinity, the degree of the spatial arrangement of the structure, micromechanical properties, and the surface morphology and thickness of a plastically deformed upper layer. These changes are the effect of work in a polymer-metal kinematic pair, which have occurred as a result of plastic deformation of polyethylene during its service. It has been shown that, as a result of selecting proper parameters of UHMW polyethylene via the initial draft and electron-beam irradiation, such a structure of the polymer can be obtained, which will enable the above-mentioned changes in morphology and structure to take place during service. This in turn, will allow a reduction of the susceptibility of the polymer to permanent deformation by 3-6 times, and its wear by more than 5 times, compared to the initial material.

  20. Expression of VHL Causes Three-Dimensional Morphological Changes in Renal Cells Indicative of Proximal Tubule Differentiation

    PubMed Central

    Chiatar, Shivannah S; Eze, Ogechukwu P; Schoenfeld, Alan R

    2013-01-01

    Mutations in the von Hippel-Lindau (VHL) tumor suppressor gene are responsible for the VHL hereditary cancer syndrome, and are associated with the majority of clear cell renal cell carcinomas. In this study, scanning electron microscopy of VHL-negative renal carcinoma cells was utilized to examine the effects of VHL re-expression on the morphology of these cells. Significant differences were observed between the morphology of VHL-negative control cells and those with reintroduced VHL, with VHL expression mediating an apical surface that mounded upward, as opposed to the flat surfaces seen with VHL-negative cells. In long term cultures, rounded VHL-expressing cells grew in clusters on top the monolayer, and microvilli were observed on the apical face of these cells, in a manner suggestive of proximal tubule differentiation. In contrast, VHL-negative cells remained flat and did not develop microvilli in long-term cultures. Since VHL is a key member of an ubiquitin E3 ligase complex whose best known target is hypoxia-inducible factor alpha (HIF-α), we looked at the effects of HIF-α expression on cell morphology. Knockdown of HIF-2α in cells that only express this isoform had no effect on the morphology of the cells. These results indicate that VHL expression directs three dimensional morphological changes in renal cells indicative of differentiation, and while dysregulation of HIF-α may be necessary for tumorigenesis following VHL loss, it is not the major determinant of these VHL-mediated morphological changes. PMID:24308012

  1. Surface morphology changes of lignin filled natural rubber latex films investigated using AFM in relation to tensile strengths

    NASA Astrophysics Data System (ADS)

    Asrul, M.; Othman, M.; Zakaria, M.

    2015-07-01

    The paper describes the preparation of lignin filled natural rubber latex composite and the consequential changes in tensile strength observed with varying lignin loading. The changes in tensile strength were shown to be associated with the changes in surface morphology as investigated via AFM. From the AFM analysis it can be inferred that lignin filled rubber latex film which exhibited an increase in tensile strength also demonstrated better phase homogeneity with lowest surface roughness value in comparison to the rest of the lignin filled rubber latex films analysed.

  2. The impact of run-off change on physical instream habitats and its response to river morphology

    NASA Astrophysics Data System (ADS)

    Hauer, Christoph; Habersack, Helmut

    2010-05-01

    Rivers have already been substantially altered by human activity. Channelization, flow regulation, or changes in land use, especially urbanization, significantly alter the water discharge, sediment transport, and morphology of rivers. The impacts of these anthropogenic measures (disturbances) on river morphology and instream habitats were frequently investigated by the scientific community over the last decades. However, there are forms of disturbances (often induced by climate change) which cause at the beginning only a slight but (over the years) a continuous degradation of aquatic habitats (and river morphology). In the presented study the impact of such disturbances caused by climate change on summer run-off was investigated within the Gr. Mühl River catchment, Austria. So far, various studies have documented the impact of run-off change on river morphology and/or sediment load. Further the impact of run-off change on aquatic ecology (target fish species) have been documented throughout various scientific papers. However, there is a lack of knowledge how (climate induced) run-off changes affect instream aquatic habitats concerning various morphological patterns (e.g. riffle-pool morphology vs. plane bed river). Thus, the aim of the presented study was to link the impacts of climate change (e.g. reduced summer run-off) to various morphological types (riffle-pool, plane bed) using habitat modelling (2-dimensional) as integrative evaluation method. As target fish species sub-adult/adult grayling was selected due to the fact, that Thymallus thymallus features especially high sensitivity in water depth (microhabitat use). Further grayling was one the historically dominant fish species for the hyporhithral catchment of the Gr. Mühl River. Within the catchment 80% of the total river length are determined as plane bed river and 20 % as riffle-pool reaches (situated in former fine material deposits). Six reaches (3 plane-bed, 3 riffle-pool) were selected and surveyed

  3. The morphological changes in lymphoid organs and peripheral blood indicators in rats after peroral administration of gold nanoparticles

    NASA Astrophysics Data System (ADS)

    Bucharskaya, A. B.; Pakhomy, S. S.; Zlobina, O. V.; Maslyakova, G. N.; Matveeva, O. V.; Bugaeva, I. O.; Navolokin, N. A.; Khlebtsov, B. N.; Bogatyrev, V. A.; Khlebtsov, N. G.; Tuchin, V. V.

    2016-03-01

    The wide application of nanotechnologies in medicine requires the careful study of various aspects of their potential safety. The effects of prolonged peroral administration of gold nanoparticles on morphological changes in lymphoid organs and indicators of peripheral blood of laboratory animals were investigated in experiment. The gold nanospheres functionalized with thiolated polyethylene glycol sizes 2, 15 and 50 nm were administered orally for 15 days to outbred white rats at a dosage of 190 μg/kg of animal body weight. The standard histological and hematological staining were used for morphological study of lymphoid organs and bone marrow smears. The size-dependent decrease of the number of neutrophils and lymphocytes was noted in the study of peripheral blood, especially pronounced after administration of gold nanoparticles with size of 50 nm. The stimulation of myelocytic germ of hematopoiesis was recorded at morphological study of the bone marrow. The signs of strengthening of the processes of differentiation and maturation of cellular elements were found in lymph nodes, which were showed as the increasing number of immunoblasts and large lymphocytes. The quantitative changes of cellular component morphology of lymphoid organs due to activation of migration, proliferation and differentiation of immune cells indicate the presence of immunostimulation effect of gold nanoparticles.

  4. Identifying heterogeneity in rates of morphological evolution: discrete character change in the evolution of lungfish (Sarcopterygii; Dipnoi).

    PubMed

    Lloyd, Graeme T; Wang, Steve C; Brusatte, Stephen L

    2012-02-01

    Quantifying rates of morphological evolution is important in many macroevolutionary studies, and critical when assessing possible adaptive radiations and episodes of punctuated equilibrium in the fossil record. However, studies of morphological rates of change have lagged behind those on taxonomic diversification, and most authors have focused on continuous characters and quantifying patterns of morphological rates over time. Here, we provide a phylogenetic approach, using discrete characters and three statistical tests to determine points on a cladogram (branches or entire clades) that are characterized by significantly high or low rates of change. These methods include a randomization approach that identifies branches with significantly high rates and likelihood ratio tests that pinpoint either branches or clades that have significantly higher or lower rates than the pooled rate of the remainder of the tree. As a test case for these methods, we analyze a discrete character dataset of lungfish, which have long been regarded as "living fossils" due to an apparent slowdown in rates since the Devonian. We find that morphological rates are highly heterogeneous across the phylogeny and recover a general pattern of decreasing rates along the phylogenetic backbone toward living taxa, from the Devonian until the present. Compared with previous work, we are able to report a more nuanced picture of lungfish evolution using these new methods. PMID:22276532

  5. Little evidence for morphological change in a resilient endemic species following the introduction of a novel predator.

    PubMed

    Sharpe, D M T; Langerhans, R B; Low-Décarie, E; Chapman, L J

    2015-11-01

    Human activities, such as species introductions, are dramatically and rapidly altering natural ecological processes and often result in novel selection regimes. To date, we still have a limited understanding of the extent to which such anthropogenic selection may be driving contemporary phenotypic change in natural populations. Here, we test whether the introduction of the piscivorous Nile perch, Lates niloticus, into East Africa's Lake Victoria and nearby lakes coincided with morphological change in one resilient native prey species, the cyprinid fish Rastrineobola argentea. Drawing on prior ecomorphological research, we predicted that this novel predator would select for increased allocation to the caudal region in R. argentea to enhance burst-swimming performance and hence escape ability. To test this prediction, we compared body morphology of R. argentea across space (nine Ugandan lakes differing in Nile perch invasion history) and through time (before and after establishment of Nile perch in Lake Victoria). Spatial comparisons of contemporary populations only partially supported our predictions, with R. argentea from some invaded lakes having larger caudal regions and smaller heads compared to R. argentea from uninvaded lakes. There was no clear evidence of predator-associated change in body shape over time in Lake Victoria. We conclude that R. argentea have not responded to the presence of Nile perch with consistent morphological changes and that other factors are driving observed patterns of body shape variation in R. argentea. PMID:26278629

  6. Control of Carbon Nanotube Morphology by Change of Applied Bias Field During Growth

    SciTech Connect

    Chen, L H.; AuBuchon, J F.; Gapin, A; Daraio, C; Bandaru, P; Jin, Sungho; Kim, D. W.; Yoo, I K.; Wang, Chong M.

    2004-10-21

    Carbon nanotube morphology has been engineered via simple control of applied voltage during dc plasma chemical vapor deposition growth. Below a critical applied voltage, a nanotube configuration of vertically aligned tubes with a constant diameter is obtained. Above the critical voltage, a nanocone-type configuration is obtained. The strongly field-dependent transition in morphology is attributed primarily to the plasma etching and decrease in the size of nanotube-nucleating catalyst particles. A two-step control of applied voltage allows a creation of dual-structured nanotube morphology consisting of a broad base nanocone ({approx}200 nm dia.) with a small diameter nanotube ({approx}7 nm) vertically emanating from the apex of the nanocone, which may be useful for atomic force microscopy.

  7. Using Remote-sensing to Survey Topography and Morphologic Change on Large Braided River Beds

    NASA Astrophysics Data System (ADS)

    Maurice, D.; Hicks, M.; Shankar, U.

    2007-12-01

    Since 1999 we have made extensive use of a variety of remote-sensing technologies to survey bed topography over reaches of large braided gravel-bed rivers on the east coast of New Zealand's South Island. The motivations have been (i) to collect input and validation data for 2-d hydrodynamic models for quantifying in-stream physical habitat and for predicting flood levels and (ii) to survey spatially-distributed riverbed erosion and deposition in order to estimate bedload fluxes by the 'morphological' method. Typical applications have been to river reaches 3-4 km long and 1 km wide, with grid cells from 1-5 m. We use different techniques to survey dry and wet areas of braided riverbed. For dry areas, we have used digital photogrammetry and infra-red airborne LiDAR. For wetted channels, we have generally used ortho-rectified colour imagery or multi-spectral scanning to map water depth, then we map bed topography by subtracting the water depth from a DEM of the water surface obtained from photogrammetry or LiDAR. The imagery is calibrated to water depth using field measurements on the day of imagery acquisition. Surveys are undertaken during low flows to maximise bed exposure. We use ground-based RTK-GPS and echo-sounding to collect calibration and validation data, and sometimes simply use these methods to survey the wetted areas. Orthoimagery at multiple river flows is used to validate 2-d model results. We have been able to achieve elevation accuracies at interpolated points of the order of 10-15 cm for dry areas. This accuracy typically degrades to 20-30 cm for wetted areas. Our experience has exposed a number of issues relating to survey accuracy and practicality at large river scales. These include: changing geoidal models between surveys; local systematic error with photogrammetric model mosaics; geospatial synchronisation of multi-platform data; time-synchronisation of LiDAR and imagery- collecting aeroplanes and suitable weather and river conditions

  8. Phase, compositional, and morphological changes of human dentin after Nd:YAG laser treatment.

    PubMed

    Lin, C P; Lee, B S; Lin, F H; Kok, S H; Lan, W H

    2001-06-01

    Although techniques for repairing root fracture have been proposed, the prognosis is generally poor. If the fusion of a root fracture by laser is possible, it will offer an alternative to extraction. Our group has attempted to use lasers to fuse a low melting-point bioactive glass to fractured dentin. This report is focused on the phase, compositional, and morphological changes observed by means of X-ray diffractometer, Fourier transforming infrared spectroscopy, and scanning electron microscopy-energy dispersive X-ray spectroscopy in human dentin after exposure to Nd:YAG laser. The irradiation energies were from 150 mJ/ pulse-10 pps-4 s to 150 mJ/pulse-30 pps-4 s. After exposure to Nd:YAG laser, dentin showed four peaks on the X-ray diffractometer that corresponding to a-tricalcium phosphate (TCP) and beta-TCP at 20 = 30.78 degrees/34.21 degrees and 32.47 degrees/33.05 degrees, respectively. The peaks of a-TCP and beta-TCP gradually increased in intensity with the elevation of irradiation energy. In Fourier transforming infrared analysis, two absorption bands at 2200 cm(-1) and 2015 cm(-1) could be traced on dentin treated by Nd:YAG laser with the irradiation energies beyond 150 mJ/pulse-10 pps-4 s. The energy dispersive X-ray results showed that the calcium/phosphorus ratios of the irradiated area proportionally increased with the elevation of irradiation energy. The laser energies of 150 mJ/ pulse-30 pps-4 s and 150 mJ/pulse-20 pps-4 s could result in the a-TCP formation and collagen breakdown. However, the formation of glass-like melted substances without a-TCP at the irradiated site was induced by the energy output of 150 mJ/ pulse-10 pps-4 s. Scanning electron micrographs also revealed that the laser energy of 150 mJ/ pulse-10 pps-4 s was sufficient to prompt melting and recrystallization of dentin crystals without cracking. Therefore, we suggest that the irradiation energy of Nd:YAG laser used to fuse a low melting-point bioactive glass to dentin is 150 m

  9. Impacts of storm chronology on the morphological changes of the Formby beach and dune system, UK

    NASA Astrophysics Data System (ADS)

    Dissanayake, P.; Brown, J.; Karunarathna, H.

    2015-04-01

    Impacts of storm chronology within a storm cluster on beach/dune erosion are investigated by applying the state-of-the-art numerical model XBeach to the Sefton coast, northwest England. Six temporal storm clusters of different storm chronologies were formulated using three storms observed during the 2013/14 winter. The storm power values of these three events nearly halve from the first to second event and from the second to third event. Cross-shore profile evolution was simulated in response to the tide, surge and wave forcing during these storms. The model was first calibrated against the available post-storm survey profiles. Cumulative impacts of beach/dune erosion during each storm cluster were simulated by using the post-storm profile of an event as the pre-storm profile for each subsequent event. For the largest event the water levels caused noticeable retreat of the dune toe due to the high water elevation. For the other events the greatest evolution occurs over the bar formations (erosion) and within the corresponding troughs (deposition) of the upper beach profile. The sequence of events impacting the size of this ridge-runnel feature is important as it consequently changes the resilience of the system to the most extreme event that causes dune retreat. The highest erosion during each single storm event was always observed when that storm initialised the storm cluster. The most severe storm always resulted in the most erosion during each cluster, no matter when it occurred within the chronology, although the erosion volume due to this storm was reduced when it was not the primary event. The greatest cumulative cluster erosion occurred with increasing storm severity; however, the variability in cumulative cluster impact over a beach/dune cross-section due to storm chronology is minimal. Initial storm impact can act to enhance or reduce the system resilience to subsequent impact, but overall the cumulative impact is controlled by the magnitude and number of

  10. Impacts of storm chronology on the morphological changes of the Formby beach and dune system, UK

    NASA Astrophysics Data System (ADS)

    Dissanayake, P.; Brown, J.; Karunarathna, H.

    2015-07-01

    Impacts of storm chronology within a storm cluster on beach/dune erosion are investigated by applying the state-of-the-art numerical model XBeach to the Sefton coast, northwest England. Six temporal storm clusters of different storm chronologies were formulated using three storms observed during the 2013/2014 winter. The storm power values of these three events nearly halve from the first to second event and from the second to third event. Cross-shore profile evolution was simulated in response to the tide, surge and wave forcing during these storms. The model was first calibrated against the available post-storm survey profiles. Cumulative impacts of beach/dune erosion during each storm cluster were simulated by using the post-storm profile of an event as the pre-storm profile for each subsequent event. For the largest event the water levels caused noticeable retreat of the dune toe due to the high water elevation. For the other events the greatest evolution occurs over the bar formations (erosion) and within the corresponding troughs (deposition) of the upper-beach profile. The sequence of events impacting the size of this ridge-runnel feature is important as it consequently changes the resilience of the system to the most extreme event that causes dune retreat. The highest erosion during each single storm event was always observed when that storm initialised the storm cluster. The most severe storm always resulted in the most erosion during each cluster, no matter when it occurred within the chronology, although the erosion volume due to this storm was reduced when it was not the primary event. The greatest cumulative cluster erosion occurred with increasing storm severity; however, the variability in cumulative cluster impact over a beach/dune cross section due to storm chronology is minimal. Initial storm impact can act to enhance or reduce the system resilience to subsequent impact, but overall the cumulative impact is controlled by the magnitude and number

  11. Morphological changes at Mt. Etna detected by TanDEM-X

    NASA Astrophysics Data System (ADS)

    Wegmuller, Urs; Bonforte, Alessandro; De Beni, Emanuela; Guglielmino, Francesco; Strozzi, Tazio

    2014-05-01

    the 2012 TanDEM-X model with the 2000 SRTM DEM in order to evaluate the morphological changes occurred on the volcano during the 12 years time lap. The pixel size of SRTM-DEM is about 90 m and we resampled the TanDEM-X model to fit this value. The results show that most of the variations occurred in the Valle del Bove and on the summit crater areas. In order to compare DEMs with the same pixel size, we performed a further comparison with a 5m ground resolution optical DEM, produced in 2004 and covering only the summit area. The variations in topography have been compared with ground mapping surveys, confirming a good correlation with the spatial extension of the lava flows and of the pyroclastic deposits occurred on Mt. Etna in the last seven years. The comparison between the two DEM's (2004-2012) allows calculating the amount of volcanics emitted and to clearly monitoring the growth and development of the New South East Crater (NSEC). TanDEM-X is a useful tools to monitor volcanic area characterized by a quit frequent activity (a paroxysm every 5-10 days), such us Mt. Etna, especially if concentrated in areas not easily accessible.

  12. Morphological and community changes of turf algae in competition with corals

    NASA Astrophysics Data System (ADS)

    Cetz-Navarro, Neidy P.; Quan-Young, Lizette I.; Espinoza-Avalos, Julio

    2015-08-01

    The morphological plasticity and community responses of algae competing with corals have not been assessed. We evaluated eight morphological characters of four species of stoloniferous clonal filamentous turf algae (FTA), including Lophosiphonia cristata (Lc) and Polysiphonia scopulorum var. villum (Psv), and the composition and number of turf algae (TA) in competition for space with the coral Orbicella spp. under experimental and non-manipulated conditions. All FTA exhibited morphological responses, such as increasing the formation of new ramets (except for Psv when competing with O. faveolata). Opposite responses in the space between erect axes were found when Psv competed with O. faveolata and when Lc competed with O. annularis. The characters modified by each FTA species, and the number and composition of TA species growing next to coral tissue differed from that of the TA growing at ≥3 cm. The specific and community responses indicate that some species of TA can actively colonise coral tissue and that fundamental competitive interactions between the two types of organisms occur within the first millimetres of the coral-algal boundary. These findings suggest that the morphological plasticity, high number, and functional redundancy of stoloniferous TA species favour their colonisation of coral tissue and resistance against coral invasion.

  13. Developmental Changes in Morphology of the Middle and Posterior External Cranial Base in Modern Homo sapiens

    PubMed Central

    Dalal, Deepal H.; Smith, Heather F.

    2015-01-01

    The basicranium has been described as phylogenetically informative, developmentally stable, and minimally affected by external factors and consequently plays an important role in cranial size and shape in subadult humans. Here basicranial variation of subadults from several modern human populations was investigated and the impact of genetic relatedness on basicranial morphological similarities was investigated. Three-dimensional landmark data were digitized from subadult basicrania from seven populations. Published molecular data on short tandem repeats were statistically compared to morphological data from three ontogenetic stages. Basicranial and temporal bone morphology both reflect genetic distances in childhood and adolescence (5–18 years), but not in infancy (<5 years). The occipital bone reflects genetic distances only in adolescence (13–18 years). The sphenoid bone does not reflect genetic distances at any ontogenetic stage but was the most diagnostic region evaluated, resulting in high rates of correct classification among populations. These results suggest that the ontogenetic processes driving basicranial development are complex and cannot be succinctly summarized across populations or basicranial regions. However, the fact that certain regions reflect genetic distances suggests that the morphology of these regions may be useful in reconstructing population history in specimens for which direct DNA evidence is unavailable, such as archaeological sites. PMID:26413515

  14. Morphological and community changes of turf algae in competition with corals

    PubMed Central

    Cetz-Navarro, Neidy P.; Quan-Young, Lizette I.; Espinoza-Avalos, Julio

    2015-01-01

    The morphological plasticity and community responses of algae competing with corals have not been assessed. We evaluated eight morphological characters of four species of stoloniferous clonal filamentous turf algae (FTA), including Lophosiphonia cristata (Lc) and Polysiphonia scopulorum var. villum (Psv), and the composition and number of turf algae (TA) in competition for space with the coral Orbicella spp. under experimental and non-manipulated conditions. All FTA exhibited morphological responses, such as increasing the formation of new ramets (except for Psv when competing with O. faveolata). Opposite responses in the space between erect axes were found when Psv competed with O. faveolata and when Lc competed with O. annularis. The characters modified by each FTA species, and the number and composition of TA species growing next to coral tissue differed from that of the TA growing at ≥3 cm. The specific and community responses indicate that some species of TA can actively colonise coral tissue and that fundamental competitive interactions between the two types of organisms occur within the first millimetres of the coral−algal boundary. These findings suggest that the morphological plasticity, high number, and functional redundancy of stoloniferous TA species favour their colonisation of coral tissue and resistance against coral invasion. PMID:26244816

  15. Simulation of sediment transport due to dam removal and control of morphological changes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper presents two case studies of post dam removal sedimentation in the United States. Two different one-dimensional channel evolution simulation models were used: CCHE1D and CONCEPTS, respectively. The first case is the application of CCHE1D to assess the long-term (up to 10 years) morphologi...

  16. Morphological and Structural Changes on Human Dental Enamel After Er:YAG Laser Irradiation: AFM, SEM, and EDS Evaluation

    PubMed Central

    Rodríguez-Vilchis, Laura Emma; Olea-Mejìa, Oscar Fernando; Sánchez-Flores, Ignacio; Centeno-Pedraza, Claudia

    2011-01-01

    Abstract Objective: The purpose of this study was to evaluate, using atomic force microscopy (AFM), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), the morphological and structural changes of the enamel after irradiation with the Er:YAG laser. Background data: A previous study showed that subablative Er:YAG laser irradiation produced undesirable morphological changes on the enamel surface, such as craters and cracks; however, the enamel acid resistance was not increased. Methods: Fifty-two samples of human enamel were divided into four groups (n = 13): Group I was the control (no laser irradiation), whereas Groups II, III, and IV were irradiated with the Er:YAG 100 mJ (12.7 J/cm2), 100 mJ (7.5 J/cm2), and 150 mJ (11 J/cm2), respectively, at 10 Hz with water spray. The morphological changes were observed by AFM and SEM. The weight percentages (wt%) of calcium (Ca), phosphorus (P), oxygen (O) and chlorine (Cl) were determined in the resultant craters and their periphery using EDS. Kruskal–Wallis and Mann–Whitney U tests were performed (p ≤ 0.05) to distinguish significant differences among the groups. Results: The AFM images showed cracks with depths between 250 nm and 750 nm for Groups II and IV, respectively, and the widths of these cracks were 5.37 μm and 2.58 μm. The interior of the cracks showed a rough surface. The SEM micrographs revealed morphological changes. Significant differences were detected in Ca, P, and Cl in the crater and its periphery. Conclusions: AFM observations showed triangular-shaped cracks, whereas craters and cracks were evident by SEM in all irradiated samples. It was not possible to establish a characteristic chemical pattern in the craters. PMID:21417912

  17. Variant of Helicobacter pylori CagA proteins induce different magnitude of morphological changes in gastric epithelial cells.

    PubMed

    Alfizah, Hanafiah; Ramelah, Mohamed

    2012-06-01

    Infection with Helicobacter pylori cagA-positive strains is associated with gastroduodenal diseases. The CagA protein is injected into gastric epithelial cells and supposedly induces morphological changes termed the 'hummingbird phenotype', which is associated with scattering and increased cell motility. The molecular mechanisms leading to the CagA-dependent morphological changes are only partially known. The present study was carried out to investigate the effect of CagA variants on the magnitude of gastric epithelial cell morphological changes. Recombinant 3' terminal domains of cagA were cloned and expressed in a gastric epithelial cell line and the hummingbird phenotype was quantified by microscopy. The 3' region of the cagA gene of Malaysian H. pylori isolates showed six sub-genotypes that differed in the structural organization of the EPIYA repeat sequences. The percentage of hummingbird cells induced by CagA increased with duration of transfection. The hummingbird phenotype was observed to be more pronounced when CagA with 4 EPIYA motifs rather than 3 or 2 EPIYA motifs was produced. The activity of different CagA variants in the induction of the hummingbird phenotype in gastric epithelial cells depends at least in part on EPIYA motif variability. The difference in CagA genotypes might influence the potential of individual CagAs to cause morphological changes in host cells. Depending on the relative exposure of cells to CagA genotypes, this may contribute to the various disease outcomes caused by H. pylori infection in different individuals. PMID:22870595

  18. Subsecond Morphological Changes in Nafion during Water Uptake Detected by Small-Angle X-ray Scattering

    SciTech Connect

    Kusoglu, Ahmet; Modestino, Miguel A.; Hexemer, Alexander; Segalman, Rachel A.; Weber, Adam Z.

    2011-11-09

    The ability of the Nafion membrane to absorb water rapidly and create a network of hydrated interconnected water domains provides this material with an unmatched ability to conduct ions through a chemically and mechanically robust membrane. The morphology and composition of these hydrated membranes significantly affects their transport properties and performance. This research demonstrates that differences in interfacial interactions between the membranes exposed to vapor or liquid water can cause significant changes in kinetics of water uptake. In situ small-angle X-ray scattering (SAXS) experiments captured the rapid swelling of the membrane in liquid water with a nanostructure rearrangement on the order of seconds. For membranes in contact with water vapor, morphological changes are four orders-of-magnitude slower than in liquid water, suggesting that interfacial resistance limits the penetration of water into the membrane. Furthermore, upon water absorption from liquid water, a structural rearrangement from a distribution of spherical and cylindrical domains to exclusively cylindrical-like domains is suggested. These differences in water-uptake kinetics and morphology provide a new perspective into Schroeder's paradox, which dictates a different water content for vapor- and liquid-equilibrated ionomers at unit activity. Lastly, the findings of this work provide critical insights into the fast kinetics of water absorption of the Nafion membrane, which can aid in the design of energy conversion devices that operate under frequent changes in environmental conditions.

  19. Dynamic Changes of QRS Morphology of Premature Ventricular Contractions During Ablation in the Right Ventricular Outflow Tract: A Case Report.

    PubMed

    Yue-Chun, Li; Jia-Feng, Lin; Jia-Xuan, Lin

    2015-10-01

    Electrocardiographic characteristics can be useful in differentiating between right ventricular outflow tract (RVOT) and aortic sinus cusp (ASC) ventricular arrhythmias. Ventricular arrhythmias originating from ASC, however, show preferential conduction to RVOT that may render the algorithms of electrocardiographic characteristics less reliable. Even though there are few reports describing ventricular arrhythmias with ASC origins and endocardial breakout sites of RVOT, progressive dynamic changes in QRS morphology of the ventricular arrhythmias during ablation obtained were rare.This case report describes a patient with symptomatic premature ventricular contractions of left ASC origin presenting an electrocardiogram (ECG) characteristic of right ventricular outflow tract before ablation. Pacing at right ventricular outflow tract reproduced an excellent pace map. When radiofrequency catheter ablation was applied to the right ventricular outflow tract, the QRS morphology of premature ventricular contractions progressively changed from ECG characteristics of right ventricular outflow tract origin to ECG characteristics of left ASC origin.Successful radiofrequency catheter ablation was achieved at the site of the earliest ventricular activation in the left ASC. The distance between the successful ablation site of the left ASC and the site with an excellent pace map of the RVOT was 20 mm.The ndings could be strong evidence for a preferential conduction via the myocardial bers from the ASC origin to the breakout site in the right ventricular outflow tract. This case demonstrates that ventricular arrhythmias with a single origin and exit shift may exhibit QRS morphology changes. PMID:26496347

  20. Genomic and physiological responses to strong selective pressure during late organogenesis: few gene expression changes found despite striking morphological differences

    PubMed Central

    2013-01-01

    Background Adaptations to a new environment, such as a polluted one, often involve large modifications of the existing phenotypes. Changes in gene expression and regulation during critical developmental stages may explain these phenotypic changes. Embryos from a population of the teleost fish, Fundulus heteroclitus, inhabiting a clean estuary do not survive when exposed to sediment extract from a site highly contaminated with polycyclic aromatic hydrocarbons (PAHs) while embryos derived from a population inhabiting a PAH polluted estuary are remarkably resistant to the polluted sediment extract. We exposed embryos from these two populations to surrogate model PAHs and analyzed changes in gene expression, morphology, and cardiac physiology in order to better understand sensitivity and adaptive resistance mechanisms mediating PAH exposure during development. Results The synergistic effects of two model PAHs, an aryl hydrocarbon receptor (AHR) agonist (β-naphthoflavone) and a cytochrome P4501A (CYP1A) inhibitor (α-naphthoflavone), caused significant developmental delays, impaired cardiac function, severe morphological alterations and failure to hatch, leading to the deaths of reference embryos; resistant embryos were mostly unaffected. Unexpectedly, patterns of gene expression among normal and moderately deformed embryos were similar, and only severely deformed embryos showed a contrasting pattern of gene expression. Given the drastic morphological differences between reference and resistant embryos, a surprisingly low percentage of genes, 2.24% of 6,754 analyzed, show statistically significant differences in transcript levels during late organogenesis between the two embryo populations. Conclusions Our study demonstrates important contrasts in responses between reference and resistant natural embryo populations to synergistic effects of surrogate model PAHs that may be important in adaptive mechanisms mediating PAH effects during fish embryo development. These

  1. Open and closed evolutionary paths for drastic morphological changes, involving serial gene duplication, sub-functionalization, and selection

    PubMed Central

    Abe, Gembu; Lee, Shu-Hua; Li, Ing-Jia; Chang, Chun-Ju; Tamura, Koji; Ota, Kinya G.

    2016-01-01

    Twin-tail goldfish strains are examples of drastic morphological alterations that emerged through domestication. Although this mutation is known to be caused by deficiency of one of two duplicated chordin genes, it is unknown why equivalent mutations have not been observed in other domesticated fish species. Here, we compared the chordin gene morphant phenotypes of single-tail goldfish and common carp (close relatives, both of which underwent chordin gene duplication and domestication). Morpholino-induced knockdown depleted chordin gene expression in both species; however, while knockdown reproduced twin-tail morphology in single-tail goldfish, it had no effect on common carp morphology. This difference can be explained by the observation that expression patterns of the duplicated chordin genes overlap completely in common carp, but are sub-functionalized in goldfish. Our finding implies that goldfish drastic morphological changes might be enhanced by the subsequent occurrence of three different types of evolutionary event (duplication, sub-functionalization, and selection) in a certain order. PMID:27220684

  2. Open and closed evolutionary paths for drastic morphological changes, involving serial gene duplication, sub-functionalization, and selection.

    PubMed

    Abe, Gembu; Lee, Shu-Hua; Li, Ing-Jia; Chang, Chun-Ju; Tamura, Koji; Ota, Kinya G

    2016-01-01

    Twin-tail goldfish strains are examples of drastic morphological alterations that emerged through domestication. Although this mutation is known to be caused by deficiency of one of two duplicated chordin genes, it is unknown why equivalent mutations have not been observed in other domesticated fish species. Here, we compared the chordin gene morphant phenotypes of single-tail goldfish and common carp (close relatives, both of which underwent chordin gene duplication and domestication). Morpholino-induced knockdown depleted chordin gene expression in both species; however, while knockdown reproduced twin-tail morphology in single-tail goldfish, it had no effect on common carp morphology. This difference can be explained by the observation that expression patterns of the duplicated chordin genes overlap completely in common carp, but are sub-functionalized in goldfish. Our finding implies that goldfish drastic morphological changes might be enhanced by the subsequent occurrence of three different types of evolutionary event (duplication, sub-functionalization, and selection) in a certain order. PMID:27220684

  3. [Morphological characteristics of the changes in the skeletal muscle tissue in acute experimental ischemia of the extremities].

    PubMed

    Savel'ev, V S; Chekareva, G A; Mishnev, O D; Bogdanov, O A

    1985-05-01

    A comprehensive morphological study of the ischemic skeletal muscles of the limbs was performed in experiments on dogs. Ischemia of the muscle tissue was induced by artificial embolic occlusion of the terminal part of the aorta. A quantitative functional and morphological study revealed serious disturbances in metabolism of the skeletal muscle that was subjected to a 6-hour ischemia. Depression of aerobic metabolism, ineffectiveness of anaerobic glycolysis (a spare pathway of the synthesis of macroergic substances), a dramatic lowering of ATPase activity, and activation of acid phosphatase in experiments of such a duration are important signs of a probably compromised adaptation process and irreversibility of the lesions in the tissue. The data should be taken into consideration in determining the optimal periods of the blood flow recovery in the limbs. Morphological changes in muscle fibers under ischemia progress with an increase in the experiment duration (up to 9 and 12 h). An important morphological sign of ischemia is a disturbed typification of muscle fibers. PMID:4005420

  4. Impacts of Sea Level Rise and Morphological Changes on Tidal Hydrodynamics in the Northern Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Passeri, D. L.; Hagen, S. C.; Plant, N. G.; Bilskie, M. V.

    2014-12-01

    Sea level rise (SLR) threatens coastal environments with increased erosion, inundation of wetlands, and changes in hydrodynamic patterns. Planning for the effects of SLR requires understanding the coupled response of SLR, geomorphic and hydrodynamic processes; this will provide crucial information for managers to make informed decisions for human and natural communities. Evaluating changes in tidal hydrodynamics under future scenarios is a key aspect for understanding the effects of SLR on coastal systems; tidal hydrodynamics influence inundation, circulation patterns, sediment transport processes, shoreline erosion, and productivity of marshes and other species. This study evaluates the dynamic effects of SLR and morphologic change on tidal hydrodynamics along the Northern Gulf of Mexico (NGOM) coast from Mississippi to the Florida panhandle. A large-scale hydrodynamic model is used to simulate astronomic tides under present (circa 2005), and future conditions (circa 2050 and 2100). The model is modified with specific SLR scenarios, morphology, and shorelines that represent the conditions at each of the time periods. Future sea levels for the years 2050 and 2100 are determined using the Parris et al. (2012) projections. To make projections of future morphology, a Bayesian Network (BN) is implemented. The BN is used to define relationships between forcing mechanisms and coastal responses based on long-term relative SLR, mean wave height, long-term shoreline change rates, mean tidal range, geomorphic setting and coastal slope. Probabilistic predictions of future shoreline positions and dune heights are developed for each SLR scenario for the years 2050 and 2100. The Digital Elevation Model (DEM) is then updated to reflect the future morphologic changes. Comparison of present and future conditions illustrates the hydrodynamic response of the system to the changing landscape. Changes in variables such as harmonic tidal constituents, tidal range, tidal prism, tidal

  5. Changes in very fine root respiration and morphology with time since last fire in a boreal forest

    NASA Astrophysics Data System (ADS)

    Makita, Naoki; Pumpanen, Jukka; Köster, Kajar; Berninger, Frank

    2016-04-01

    We examined the physiological and morphological responses of individual fine root segments in boreal forests stands with different age since the last fire to determine changes in specific fine root respiration and morphological traits during forest succession. We investigated the respiration of fine roots divided into three diameter classes (<0.5, 0.5-1.0, and 1.0-2.0 mm) in a Finnish boreal Pinus sylvestris L. in forest stands with 5, 45, 63, and 155 years since the last fire. Specific respiration rates of <0.5 mm roots in 155-year-old stands were 74%, 38%, and 31% higher than in 5-, 45-, and 63-year-old stands, respectively. However, the respiration rates of thicker diameter roots did not significantly change among stands with respect to time after fire. Similarly, fire disturbance had a strong impact on morphological traits of <0.5 mm roots, but not on thicker roots. Root respiration rates correlated positively with specific root length (length per unit mass) and negatively with root tissue density (mass per unit volume) in all stand ages. The linear regression lines fitted to the relationships between root respiration and specific root length or root tissue density showed significantly higher intercepts in 63- and 155-year-old than in 5-year-old stands. Significant shifts in the intercept of the common slope of respiration vs. morphology indicate the different magnitude of the changes in physiological performance among the fire age class. Despite a specific small geographic area, we suggest that the recovery of boreal forests following wildfire induces a strategy that favors carbon investment in nutrient and water exploitation efficiency with consequences for higher respiration, length, and lower tissue density of very fine roots.

  6. Morphological dependence of silver electrodeposits investigated by changing the ionic liquid solvent and the deposition parameters.

    PubMed

    Figueredo-Sobrinho, Francisco A A; Santos, Luis P M; Leite, Davi S; Craveiro, Diego C; Santos, Samir H; Eguiluz, Katlin I B; Salazar-Banda, Giancarlo R; Maciel, Cleiton D; Coutinho-Neto, Maurício D; Homem-de-Mello, Paula; de Lima-Neto, Pedro; Correia, Adriana N

    2016-03-14

    The low toxicity and environmentally compatible ionic liquids (ILs) are alternatives to the toxic and harmful cyanide-based baths used in industrial silver electrodeposition. Here, we report the successful galvanostatic electrodeposition of silver films using the air and water stable ILs 1-ethyl-3-methylimidazolium trifluoromethylsulfonate ([EMIM]TfO) and 1-H-3-methylimidazolium hydrogen sulphate ([HMIM(+)][HSO4(-)]) as solvents and AgTfO as the source of silver. The electrochemical deposition parameters were thoughtfully studied by cyclic voltammetry before deposition. The electrodeposits were characterized by scanning electron microscopy coupled with X-ray energy dispersive spectroscopy and X-ray diffraction. Molecular dynamics (MD) simulations were used to investigate the structural dynamic and energetic properties of AgTfO in both ILs. Cyclic voltammetry experiments revealed that the reduction of silver is a diffusion-controlled process. The morphology of the silver coatings obtained in [EMIM]TfO is independent of the applied current density, resulting in nodular electrodeposits grouped as crystalline clusters. However, the current density significantly influences the morphology of silver electrodeposits obtained in [HMIM(+)][HSO4(-)], thus evolving from dendrites at 15 mA cm(-2) to the coexistence of dendrites and columnar shapes at 30 mA cm(-2). These differences are probably due to the greater interaction of Ag(+) with [HSO4(-)] than with TfO(-), as indicated by the MD simulations. The morphology of Ag deposits is independent of the electrodeposition temperature for both ILs, but higher values of temperature promoted increased cluster sizes. Pure face-centred cubic polycrystalline Ag was deposited on the films with crystallite sizes on the nanometre scale. The morphological dependence of Ag electrodeposits obtained in the [HMIM(+)][HSO4(-)] IL on the current density applied opens up the opportunity to produce different and predetermined Ag deposits. PMID

  7. Ontogenetic development of the auditory sensory organ in zebrafish (Danio rerio): changes in hearing sensitivity and related morphology

    PubMed Central

    Wang, Jiping; Song, Qiang; Yu, Dongzhen; Yang, Guang; Xia, Li; Su, Kaiming; Shi, Haibo; Wang, Jian; Yin, Shankai

    2015-01-01

    Zebrafish (Danio rerio) is an important model organism in hearing research. However, data on the hearing sensitivity of zebrafish vary across different reports. In the present study, the hearing sensitivity of zebrafish was examined by analysing the auditory evoked potentials (AEPs) over a range of total lengths (TLs) from 12 to 46 mm. Morphological changes in the hair cells (HCs) of the saccule (the main auditory end organ) and their synapses with primary auditory neurons were investigated. The AEPs were detected up to a much higher frequency limit (12 kHz) than previously reported. No significant difference in the frequency response range was observed across the TL range examined. However, the AEP thresholds demonstrated both developmental improvement and age-related loss of hearing sensitivity. The changes in hearing sensitivity were roughly consistent with the morphological changes in the saccule including (1) the number and density of HCs, (2) the organization of stereocilia, and (3) the quantity of a main ribbon protein, Ribeye b. The results of this study established a clear baseline for the hearing ability of zebrafish and revealed that the changes in the saccule contribute to the observed changes in TL (age)-related hearing sensitivity. PMID:26526229

  8. On the polymorphic and morphological changes of cellulose nanocrystals (CNC-I) upon mercerization and conversion to CNC-II.

    PubMed

    Jin, Ersuo; Guo, Jiaqi; Yang, Fang; Zhu, Yangyang; Song, Junlong; Jin, Yongcan; Rojas, Orlando J

    2016-06-01

    Polymorphic and morphological transformations of cellulosic materials are strongly associated to their properties and applications, especially in the case of emerging nanocelluloses. Related changes that take place upon treatment of cellulose nanocrystals (CNC) in alkaline conditions are studied here by XRD, TEM, AFM, and other techniques. The results indicate polymorphic transformation of CNC proceeds gradually in a certain range of alkali concentrations, i.e. from about 8% to 12.5% NaOH. In such transition alkali concentration, cellulose I and II allomorphs coexists. Such value and range of the transition concentration is strongly interdependent with the crystallite size of CNCs. In addition, it is distinctively lower than that for macroscopic fibers (12-15% NaOH). Transmission electron microscopy and particle sizing reveals that after mercerization CNCs tend to associate. Furthermore, TEMPO-oxidized mercerized CNC reveals the morphology of individual nanocrystal of the cellulose II type, which is composed of some interconnected granular structures. Overall, this work reveals how the polymorphism and morphology of individual CNC change in alkali conditions and sheds light onto the polymorphic transition from cellulose I to II. PMID:27083376

  9. Nanoscale Morphological and Chemical Changes of High Voltage Lithium–Manganese Rich NMC Composite Cathodes with Cycling

    PubMed Central

    2015-01-01

    Understanding the evolution of chemical composition and morphology of battery materials during electrochemical cycling is fundamental to extending battery cycle life and ensuring safety. This is particularly true for the much debated high energy density (high voltage) lithium–manganese rich cathode material of composition Li1 + xM1 – xO2 (M = Mn, Co, Ni). In this study we combine full-field transmission X-ray microscopy (TXM) with X-ray absorption near edge structure (XANES) to spatially resolve changes in chemical phase, oxidation state, and morphology within a high voltage cathode having nominal composition Li1.2Mn0.525Ni0.175Co0.1O2. Nanoscale microscopy with chemical/elemental sensitivity provides direct quantitative visualization of the cathode, and insights into failure. Single-pixel (∼30 nm) TXM XANES revealed changes in Mn chemistry with cycling, possibly to a spinel conformation and likely including some Mn(II), starting at the particle surface and proceeding inward. Morphological analysis of the particles revealed, with high resolution and statistical sampling, that the majority of particles adopted nonspherical shapes after 200 cycles. Multiple-energy tomography showed a more homogeneous association of transition metals in the pristine particle, which segregate significantly with cycling. Depletion of transition metals at the cathode surface occurs after just one cycle, likely driven by electrochemical reactions at the surface. PMID:25054780

  10. Nanoscale morphological and chemical changes of high voltage lithium-manganese rich NMC composite cathodes with cycling.

    PubMed

    Yang, Feifei; Liu, Yijin; Martha, Surendra K; Wu, Ziyu; Andrews, Joy C; Ice, Gene E; Pianetta, Piero; Nanda, Jagjit

    2014-08-13

    Understanding the evolution of chemical composition and morphology of battery materials during electrochemical cycling is fundamental to extending battery cycle life and ensuring safety. This is particularly true for the much debated high energy density (high voltage) lithium-manganese rich cathode material of composition Li(1 + x)M(1 - x)O2 (M = Mn, Co, Ni). In this study we combine full-field transmission X-ray microscopy (TXM) with X-ray absorption near edge structure (XANES) to spatially resolve changes in chemical phase, oxidation state, and morphology within a high voltage cathode having nominal composition Li1.2Mn0.525Ni0.175Co0.1O2. Nanoscale microscopy with chemical/elemental sensitivity provides direct quantitative visualization of the cathode, and insights into failure. Single-pixel (∼ 30 nm) TXM XANES revealed changes in Mn chemistry with cycling, possibly to a spinel conformation and likely including some Mn(II), starting at the particle surface and proceeding inward. Morphological analysis of the particles revealed, with high resolution and statistical sampling, that the majority of particles adopted nonspherical shapes after 200 cycles. Multiple-energy tomography showed a more homogeneous association of transition metals in the pristine particle, which segregate significantly with cycling. Depletion of transition metals at the cathode surface occurs after just one cycle, likely driven by electrochemical reactions at the surface. PMID:25054780

  11. Morphologic changes in uranyl nitrate-induced acute renal failure in saline- and water-drinking rats

    SciTech Connect

    Haley, D.P.

    1982-02-01

    The sequential changes in renal morphology that occurred for 5 subsequent days after a subcutaneous injection of uranyl nitrate (10 mg. per kg.) were examined in saline- and water-drinking rats using light microscopy, transmission electron microscopy, and scanning electron microscopy. The cortical proximal tubule exhibited diffuse focal brush border loss and increased vacuolization by 1 hour after administration of the nephrotoxin. By 5 days, the P2 and P3 segments were completely necrotic. Cells of P1 segments accumulated large vacuoles throughout their cytoplasm, and distal nephron segments exhibited considerable cellular swelling and vacuolization. Scanning electron microscopy revealed abnormalities in glomerular epithelial cells similar to those seen in humans with chronic renal disease and in experimental animal models characterized by proteinuria. There was essentially no difference in the morphologic response of saline- and water-drinking rats. Although uranyl nitrate administered at this dosage resulted in the relatively slow development of tubular necrosis, changes in renal morphology could be seen within an hour and progressed insidiously throughout the study with little evidence of regeneration.

  12. Historical GIS Data and Changes in Urban Morphological Parameters for the Analysis of Urban Heat Islands in Hong Kong

    NASA Astrophysics Data System (ADS)

    Peng, F.; Wong, M. S.; Nichol, J. E.; Chan, P. W.

    2016-06-01

    Rapid urban development between the 1960 and 2010 decades have changed the urban landscape and pattern in the Kowloon Peninsula of Hong Kong. This paper aims to study the changes of urban morphological parameters between the 1985 and 2010 and explore their influences on the urban heat island (UHI) effect. This study applied a mono-window algorithm to retrieve the land surface temperature (LST) using Landsat Thematic Mapper (TM) images from 1987 to 2009. In order to estimate the effects of local urban morphological parameters to LST, the global surface temperature anomaly was analysed. Historical 3D building model was developed based on aerial photogrammetry technique using aerial photographs from 1964 to 2010, in which the urban digital surface models (DSMs) including elevations of infrastructures and buildings have been generated. Then, urban morphological parameters (i.e. frontal area index (FAI), sky view factor (SVF)), vegetation fractional cover (VFC), global solar radiation (GSR), Normalized Difference Built-Up Index (NDBI), wind speed were derived. Finally, a linear regression method in Waikato Environment for Knowledge Analysis (WEKA) was used to build prediction model for revealing LST spatial patterns. Results show that the final apparent surface temperature have uncertainties less than 1 degree Celsius. The comparison between the simulated and actual spatial pattern of LST in 2009 showed that the correlation coefficient is 0.65, mean absolute error (MAE) is 1.24 degree Celsius, and root mean square error (RMSE) is 1.51 degree Celsius of 22,429 pixels.

  13. Physiological and morphological colour change in Antarctic krill, Euphausia superba: a field study in the Lazarev Sea.

    PubMed

    Auerswald, Lutz; Freier, Ulrich; Lopata, Andreas; Meyer, Bettina

    2008-12-01

    Antarctic krill, Euphausia superba, is very susceptible to harmful solar radiation because of its unique genetic setup. Exposure occurs in spring to autumn during vertical diel migration and during occasional daytime surface-swarming. We have investigated colour change in Antarctic krill, Euphausia superba, during summer and winter in the Lazarev Sea in response to ultraviolet radiation (UVR) and photosynthetically active radiation (PAR). Short-term physiological colour change and long-term (seasonal) morphological colour change are present. Both are facilitated by a single type of monochromatic red chromatophore, i.e. erythrophores, of 20-450 microm diameter. Superficial erythrophores cover large dorsal areas, especially above vital organs (brain, sinus glands), additional 'profound' erythrophores cover internal organs (heart, gut, nerve cords). Short-term change in light regime causes rapid physiological colour change along dense bundles of microtubules: pigment disperses into chromorhizae upon exposure to PAR and UVA and to a lesser extent to UVB. Darkness leads to aggregation of pigment in the centre and hence blanching. There is no circadian rhythm in the dispersal state of erythrophores present in winter. Physiological colour change in adult krill is two to three times more rapid in summer than in winter. Furthermore, seasonal changes in light regime also result in a profound morphological colour change: in summer animals, abdominal astaxanthin concentration is 450% and erythrophore count is 250-480% higher than in winter krill. We conclude from our results, that pigmentation of E. superba serves in the protection from harmful solar radiation and is adapted to the varying diel and seasonal light conditions. PMID:19043057

  14. The physiology of adaptation to small bowel resection in the pig: an integrated study of morphological and functional changes.

    PubMed

    Sigalet, D L; Lees, G M; Aherne, F; Van Aerde, J E; Fedorak, R N; Keelan, M; Thomson, A B

    1990-06-01

    This study examined the adaptive response to extensive small intestinal resection in the juvenile domestic pig. Control animals underwent an ileal transection with end-to-end anastomosis, whereas resected pigs had a resection of the mid-75% of the total small bowel length. Animals were followed for 16 weeks. Resected animals gained less weight than controls, with no significant difference in feed intake per unit animal weight. In vivo fat, protein, carbohydrate, and total energy absorption were reduced in resected animals. Resected pigs had increased in vitro passive ileal uptake of fatty acids, cholesterol, and L-glucose, but no change in active D-glucose uptake. Microscopic morphology was altered, with an increase in the size of villi, a decrease in villous density, and no net change in mucosal surface area per unit of serosal surface area. Gross bowel length and diameter increased proportionately more in the resected than the control groups. This study demonstrated that massive resection results in a significant change in nutritional status in the growing pig. Functional and morphological changes occur, demonstrating intestinal adaptation. These findings suggest that this model would be suitable for the study of therapeutic modalities for the short-bowel syndrome in humans. PMID:2359003

  15. Morphological Changes of Paulownia Seedlings Infected Phytoplasmas Reveal the Genes Associated with Witches' Broom through AFLP and MSAP

    PubMed Central

    Cao, Xibing; Fan, Guoqiang; Zhao, Zhenli; Deng, Minjie; Dong, Yanpeng

    2014-01-01

    Paulownia witches' broom (PaWB) caused by phytoplasma might result in devastating damage to the growth and wood production of Paulownia. To study the effect of phytoplasma on DNA sequence and to discover the genes related to PaWB occurrence, DNA polymorphisms and DNA methylation levels and patterns in PaWB seedlings, the ones treated with various concentration of methyl methane sulfonate (MMS) and healthy seedlings were investigated with amplified fragment length polymorphism (AFLP) and methylation-sensitive amplification polymorphism (MSAP). Our results indicated that PaWB seedlings recovered a normal morphology, similar to healthy seedlings, after treatment with more than 20 mg·L−1 MMS; Phytoplasma infection did not change the Paulownia genomic DNA sequence at AFLP level, but changed the global DNA methylation levels and patterns; Genes related to PaWB were discovered through MSAP and validated using quantitative real-time PCR (qRT-PCR). These results implied that changes of DNA methylation levels and patterns were closely related to the morphological changes of seedlings infected with phytoplasmas. PMID:25427154

  16. Assessment of global morphological and topological changes in trabecular structure under the bone resorption process

    NASA Astrophysics Data System (ADS)

    Sidorenko, Irina N.; Bauer, Jan; Monetti, Roberto; Baum, Thomas; Rummeny, Ernst J.; Eckstein, Felix; Matsuura, Maiko; Lochmueller, Eva-Maria; Zysset, Philippe K.; Raeth, Christoph W.

    2012-03-01

    Osteoporosis is a frequent skeletal disease characterised both by loss of bone mineral mass and deterioration of cancellous bone micro-architecture. It can be caused by mechanical disuse, estrogen deficiency or natural age-related resorption process. Numerical analysis of high-resolution images of the trabecular network is recognised as a powerful tool for assessment of structural characteristics. Using μCT images of 73 thoracic and 78 lumbar human vertebral specimens in vitro with isotropic resolution of 26μm we simulate bone atrophy as random resorption of bone surface voxels. Global morphological and topological characteristics provided by four Minkowski Functionals (MF) are calculated for two numerical resorption models with and without conservation of global topological connectivity of the trabecular network, which simulates different types of bone loss in osteoporosis, as it has been described in males and females. Diagnostic performance of morphological and topological characteristics as a function of relative bone loss is evaluated by a correlation analysis with respect to experimentally measured Maximum Compressive Strength (MCS). In both resorption models the second MF, which coincides with bone surface fraction BS/TV, demonstrates almost constant value of Pearson's correlation coefficient with respect to the relative bone loss ▵BV/TV. This morphological characteristic does not vary considerably under age-related random resorption and can be used for predicting bone strength in the elderly. The third and fourth MF demonstrate an increasing correlation coefficients with MCS after applying random bone surface thinning without preserving topological connectivity, what can be used for improvement of evaluation of the current state of the structure.

  17. Morphological and molecular changes of human granulosa cells exposed to 5-azacytidine and addressed toward muscular differentiation.

    PubMed

    Brevini, Tiziana A L; Pennarossa, Georgia; Rahman, Mahbubur M; Paffoni, Alessio; Antonini, Stefania; Ragni, Guido; deEguileor, Magda; Tettamanti, Gianluca; Gandolfi, Fulvio

    2014-10-01

    Converting adult cells from one cell type to another is a particularly interesting idea for regenerative medicine. Terminally differentiated cells can be induced to de-differentiate in vitro to become multipotent progenitors. In mammals these changes do not occur naturally, however exposing differentiated adult cells to synthetic molecules capable of selectively reverting cells from their lineage commitment to a more plastic state makes it possible to re-address their fate. Only scattered information are available on the morphological changes and ultrastructural remodeling taking place when cells convert into a different and specific type. To better clarify these aspects, we derived human granulosa cell (GC) primary cultures and analyzed the morphological changes taking place in response to the exposure to the epigenetic modifier 5-azacytidine (5-aza-CR) and to the treatment with VEGF, as a stimulus for inducing differentiation into muscle cells. Ultrastructural modifications and molecular marker expression were analyzed at different intervals during the treatments. Our results indicate that the temporary up regulation of pluripotency markers is accompanied by the loss of GC-specific ultrastructural features, mainly through autophagocitosis, and is associated with a temporary chromatin decondensation. After exposure to VEGF the induction of muscle specific genes was combined with the appearance of multinucleated cells with a considerable quantity of non-spatially organized filaments. The detailed analysis of the morphological changes occurring in cells undergoing lineage re-addressing allows a better understanding of these process and may prove useful for refining the use of somatic cells in regenerative medicine and tissue replacement therapies. PMID:24858410

  18. [Morphological changes of tissues in formation of a welding suture on the large intestine].

    PubMed

    Bondar', G V; Basheev, V Kh; Borota, A V; Miroshnichenko, E Iu; Koshik, E A

    2011-01-01

    Abdominoanal resection with descending of left colon on perineum, leaving additional part of a descended intestine, was performed. For the hemorrhage arrest the welding sutures were put on intestinal wall. According to morphological investigations data, a damage of intestinal wall in the zone of a welding suture application is a reversible one, it spreads from the electrode branch on 2-3 mm. The presence of undamaged structures witnesses the presence of an active regeneration process in tissues around the welding suture. PMID:21512998

  19. Insight into morphology changes of nanoparticle laden droplets in acoustic field

    NASA Astrophysics Data System (ADS)

    Basu, Saptarshi; Tijerino, Erick; Kumar, Ranganathan

    2013-04-01

    Hollow structures with unique morphologies form due to particle agglomeration in acoustically levitated nanofluid functional droplets when subjected to external heating. The final diameter of the structure depends only on the ratio of agglomeration to evaporation time scales for various nanoparticle laden droplets, and not on the type of the suspended particles. These time scales depend only on nanoparticle concentration. This valuable information may be exploited to form microstructures with desired properties from ceramic compounds. Phase diagrams for alumina and silica droplets indicate the transition from a bowl to ring structure depending on concentration.

  20. Hemodynamic effects of long-term morphological changes in the human carotid sinus.

    PubMed

    Seong, Jaehoon; Jeong, Woowon; Smith, Nataliya; Towner, Rheal A

    2015-04-13

    Previous investigations of morphology for human carotid artery bifurcation from infancy to young adulthood found substantial growth of the internal carotid artery with advancing age, and the development of the carotid sinus at the root of the internal carotid artery during teenage years. Although the reasons for the appearance of the carotid sinus are not clearly understood yet, it has been hypothesized that the dilation of the carotid sinus serves to support pressure sensing, and slows the blood flow to reduce pulsatility to protect the brain. In order to understand this interesting evolvement at the carotid bifurcation in the aspects of fluid mechanics, we performed in vitro phase-contrast MR flow experiments using compliant silicone replicas of age-dependent carotid artery bifurcations. The silicone models in childhood, adolescence, and adulthood were fabricated using a rapid prototyping technique, and incorporated with a bench-top flow mock circulation loop using a computer-controlled piston pump. The results of the in vitro flow study showed highly complex flow characteristics at the bifurcation in all age-dependent models. However, the highest magnitude of kinetic energy was found at the internal carotid artery in the child model. The high kinetic energy in the internal carotid artery during childhood might be one of the local hemodynamic forces that initiate morphological long-term development of the carotid sinus in the human carotid bifurcation. PMID:25702250

  1. A novel biointerface that suppresses cell morphological changes by scavenging excess reactive oxygen species.

    PubMed

    Ikeda, Yutaka; Yoshinari, Tomoki; Nagasaki, Yukio

    2015-09-01

    During cell cultivation on conventional culture dishes, various events results in strong stresses that lead to the production of bioactive species such as reactive oxygen species (ROS) and nitric oxide. These reactive species cause variable damage to cells and stimulate cellular responses. Here, we report the design of a novel biocompatible surface that decreases stress by not only morphologically modifying the dish surface by using poly(ethylene glycol) tethered chains, but also actively scavenging oxidative stress by using our novel nitroxide radical-containing polymer. A block copolymer, poly(ethylene glycol)-b-poly[(2,2,6,6-tetramethylpiperidine-N-oxyl)aminomethylstyrene] (PEG-b-PMNT) was used to coat the surface of a dish. Differentiation of undifferentiated human leukemia (HL-60) cells was found to be suppressed on the polymer-coated dish. Notably, HL-60 cell cultivation caused apoptosis under high-density conditions, while spontaneous apoptosis was suppressed in cells plated on the PEG-b-PMNT-modified surface, because a healthy mitochondrial membrane potential was maintained. In contrast, low molecular weight antioxidants did not have apparent effects on the maintenance of mitochondria. We attribute this to the lack of cellular internalization of our immobilized polymer and selective scavenging of excessive ROS generated outside of cells. These results demonstrate the utility of our novel biocompatible material for actively scavenging ROS and thus maintaining cellular morphology. PMID:25691268

  2. The Ever-Changing Morphology of Hippocampal Granule Neurons in Physiology and Pathology

    PubMed Central

    Llorens-Martín, María; Rábano, Alberto; Ávila, Jesús

    2016-01-01

    Newborn neurons are continuously added to the hippocampal dentate gyrus throughout adulthood. In this review, we analyze the maturational stages that newborn granule neurons go through, with a focus on their unique morphological features during each stage under both physiological and pathological circumstances. In addition, the influence of deleterious (such as schizophrenia, stress, Alzheimer's disease, seizures, stroke, inflammation, dietary deficiencies, or the consumption of drugs of abuse or toxic substances) and neuroprotective (physical exercise and environmental enrichment) stimuli on the maturation of these cells will be examined. Finally, the regulation of this process by proteins involved in neurodegenerative and neurological disorders such as Glycogen synthase kinase 3β, Disrupted in Schizophrenia 1 (DISC-1), Glucocorticoid receptor, pro-inflammatory mediators, Presenilin-1, Amyloid precursor protein, Cyclin-dependent kinase 5 (CDK5), among others, will be evaluated. Given the recently acquired relevance of the dendritic branch as a functional synaptic unit required for memory storage, a full understanding of the morphological alterations observed in newborn neurons may have important consequences for the prevention and treatment of the cognitive and affective alterations that evolve in conjunction with impaired adult hippocampal neurogenesis. PMID:26834550

  3. Molecular Mechanism of Ionic-Liquid-Induced Membrane Disruption: Morphological Changes to Bilayers, Multilayers, and Vesicles.

    PubMed

    Yoo, Brian; Zhu, Yingxi; Maginn, Edward J

    2016-05-31

    The application of ionic liquids (ILs) in many industrially relevant processes provides an urgent need to better understand their molecular interactions with biological systems. A detailed understanding of the cytotoxicity mechanism of ILs can be helpful in facilitating the molecular design of nontoxic ILs. Using coarse-grained molecular dynamics (MD) simulations, we investigate the effects of imidazolium-based ILs on several lipid bilayer morphologies. Our results demonstrate that the asymmetric insertion of IL cations into one side of a lipid bilayer leaflet enhances the leaflet strain, which upon reaching a critical value triggers a morphological disruption in the bilayer. Consistently, the bending modulus of the bilayer is reduced by 1 to 2 orders of magnitude relative to that of an IL-free planar bilayer prior to the disruption event. Our results suggest that ILs that can easily insert into the lipid bilayer without diffusing across or inducing lipid flip-flop can be more disruptive to a lipid biomembrane. PMID:27159842

  4. Evaluating the Impacts of Land Use Change on Stream Morphology in Coastal Maine

    NASA Astrophysics Data System (ADS)

    Kasprak, A.; Magilligan, F. J.; Nislow, K. H.; Snyder, N. P.

    2009-12-01

    Intensive forestry has been occurring in Maine for centuries, and continues today, despite having the potential to adversely impact stream processes and aquatic habitat. Numerous studies have documented the morphologic effects of logging on streams in high-relief western U.S. landscapes, particularly with regard to sediment transport and large woody debris (LWD) loading. Conversely, little is known regarding the role of timber harvest on the morphology of low-relief streams, such as those of coastal Maine. We use a combination of field-based stream surveys and LiDAR-based remote sensing to determine the present disturbance state of the 78-km Narraguagus River in Downeast Maine, with specific focus on LWD loading and bedload sediment transport. Using LiDAR groundtruthed via riparian surveys, we determine the amount of channel-spanning wood currently available to the stream. We find that potential channel-spanning LWD is scarce (less than 50% of riparian area over the entire stream length). We also conduct in-channel sediment surveys (Wolman pebble counts, embeddedness surveys, and interstitial shelter space measurements) at sixteen sites on both the mainstem and its tributaries, and find that while bed over-coarsening (as compared to LiDAR-derived D50 estimates) is commonplace on the mainstem, high fine sediment concentration is a prevailing characteristic of tributary streambeds. Our ongoing research seeks to determine whether the overall lack of LWD and/or increased levels of fine sediment on tributaries are attributable to logging in the basin.

  5. Induction of morphological changes in death-induced cancer cells monitored by holographic microscopy.

    PubMed

    El-Schich, Zahra; Mölder, Anna; Tassidis, Helena; Härkönen, Pirkko; Falck Miniotis, Maria; Gjörloff Wingren, Anette

    2015-03-01

    We are using the label-free technique of holographic microscopy to analyze cellular parameters including cell number, confluence, cellular volume and area directly in the cell culture environment. We show that death-induced cells can be distinguished from untreated counterparts by the use of holographic microscopy, and we demonstrate its capability for cell death assessment. Morphological analysis of two representative cell lines (L929 and DU145) was performed in the culture flasks without any prior cell detachment. The two cell lines were treated with the anti-tumour agent etoposide for 1-3days. Measurements by holographic microscopy showed significant differences in average cell number, confluence, volume and area when comparing etoposide-treated with untreated cells. The cell volume of the treated cell lines was initially increased at early time-points. By time, cells decreased in volume, especially when treated with high doses of etoposide. In conclusion, we have shown that holographic microscopy allows label-free and completely non-invasive morphological measurements of cell growth, viability and death. Future applications could include real-time monitoring of these holographic microscopy parameters in cells in response to clinically relevant compounds. PMID:25637284

  6. Hemodynamic Effects of Long-term Morphological Changes in the Human Carotid Sinus

    PubMed Central

    Seong, Jaehoon; Jeong, Woowon; Smith, Nataliya; Towner, Rheal A.

    2015-01-01

    Previous investigations of morphology for human carotid artery bifurcation from infancy to young adulthood found substantial growth of the internal carotid artery with advancing age, and the development of the carotid sinus at the root of the internal carotid artery during teen age years. Although the reasons for the appearance of the carotid sinus are not clearly understood yet, it has been hypothesized that the dilation of the carotid sinus serves to support pressure sensing, and slows the blood flow to reduce pulsatility to protect the brain. In order to understand this interesting evolvement at the carotid bifurcation in the aspects of fluid mechanics, we performed in vitro phase-contrast MR flow experiments using compliant silicone replicas of age-dependent carotid artery bifurcations. The silicone models in childhood, adolescence, and adulthood were fabricated using a rapid prototyping technique, and incorporated with a bench-top flow mock circulation loop using a computer-controlled piston pump. The results of the in vitro flow study showed highly complex flow characteristics at the bifurcation in all age-dependent models. However, the highest magnitude of kinetic energy was found at the internal carotid artery in the child model. The high kinetic energy in the internal carotid artery during childhood might be one of the local hemodynamic forces that initiate morphological long-term development of the carotid sinus in the human carotid bifurcation. PMID:25702250

  7. Primary hepatic tumors with myxoid change: morphologically unique hepatic adenomas and hepatocellular carcinomas.

    PubMed

    Salaria, Safia N; Graham, Rondell P; Aishima, Shinichi; Mounajjed, Taofic; Yeh, Matthew M; Torbenson, Michael S

    2015-03-01

    Mucin production in primary liver neoplasms is typically interpreted as evidence for biliary differentiation. However, we have observed benign and malignant liver tumors that have abundant extracellular myxoid/mucinous material, yet have only evidence of hepatocellular differentiation. To further characterize these unusual findings, 9 cases were identified and further studied. Four cases were hepatic adenomas, whereas 5 were hepatocellular carcinomas. Extracellular myxoid/mucinous material was diffuse in 7 cases and patchy in 2 cases. The extracellular myxoid/mucinous material was typically weakly mucicarmine positive (N=6) and Alcian blue positive (N=8). All tumors were well differentiated, and none had evidence for biliary differentiation by morphology or immunohistochemistry. The hepatic adenomas arose in nondiabetic and nonobese patients. Both the hepatic adenomas and the hepatocellular carcinomas were strongly and diffusely HepPar1 positive, CK19 negative, and showed loss of LFABP protein expression. These findings indicate that extracellular myxoid/mucinous material in isolation should not be interpreted as cholangiocarcinoma. Furthermore, the unique morphology, the clinical characteristics, and the immunophenotype results suggest that myxoid hepatic adenomas and hepatocellular carcinoma may be unique tumor variants. PMID:25602798

  8. Effect of morphological changes on the hydrodynamics and flushing properties of the Óbidos lagoon (Portugal)

    NASA Astrophysics Data System (ADS)

    Oliveira, Anabela; Fortunato, André B.; Rego, João R. L.

    2006-06-01

    This paper investigates the effect of natural and artificial morphological changes in a tidal inlet on the tidal propagation and on the water exchanges with the sea, through data analysis and numerical modeling. Bathymetric and tidal data reveal a strong seasonal signal, as a result of the changes in the relative importance of tidal and wave action: during the maritime winter the M2 tidal amplitude decreases by 50% and flood dominance increases. This trend is reverted during maritime summer, and tidal amplitudes can be further enhanced by dredging of the inlet. Hydrodynamic and residence time (RT) simulations were set up for three different bathymetric configurations of the lower lagoon, representative of distinct situations. Hydrodynamic results confirmed that tidal propagation depends strongly on the bathymetric configuration. At the transitions between channels, tidal energy losses occur and flood dominance increases. Dredging the channels and repositioning the inlet throat improve tidal propagation and promote sediment flushing to the sea. The spatial variability of RTs was evaluated through the integration of individual particle results in morphologically relevant units, while time variability was examined within the tidal and neap/spring cycles. Residence times depend heavily on the morphological changes associated with both dredging operations and inlet migration, and on the particle release time, both within the tidal cycle and within neap/spring cycles. The relative importance of each of these factors depends on the particle location within the lagoon. The upstream regions of the lagoon have very large RTs (years), as a result of the small tidal amplitudes and velocities. In some of these regions, RTs vary by a factor of 4 depending on the bathymetry of the inlet. In the lower lagoon, tidal amplitude also has a significant effect on RTs. Dredging the channels and repositioning the inlet throat from the southern margin to a central position improves the

  9. Morphological and functional changes of stallion spermatozoa after cryopreservation during breeding and non-breeding season.

    PubMed

    Blottner, S; Warnke, C; Tuchscherer, A; Heinen, V; Torner, H

    2001-01-31

    The study compared quality and freezability of stallion semen during breeding and non-breeding seasons. Ejaculates were collected twice per week from four stallions during May (n = 24) and December (n = 24). The semen was mixed with skim milk extender, centrifuged and resuspended in fresh extender. Aliquots of this sperm suspension were separated from extender and diluted in TALP medium for sperm evaluation or with cryoextender (type "Gent" or a combination of Triladyl and skim milk). Samples of 0.5ml were cryopreserved in straws using a programmed freezer. Parameters of sperm quality were evaluated before and after freezing/thawing. These included percentages of motile spermatozoa and of morphological intact sperm. Typical injuries were demonstrated by scanning electron microscopy (S.E.M.). The acrosomal status was visualised using FITC-conjugated peanut agglutinin, and the acrosome reaction was induced by calcium ionophore A 23187. The chromatin stability was estimated by acridine orange test. In winter, the average percentages of motile and morphologically normal sperm (67 and 74.3%, respectively) were higher than during the breeding season in May (59 and 65.9%; P < 0.05). After freezing/thawing the proportions of vital and intact sperm decreased significantly. The number of motile sperm declined to 15 and 18% in May and December (range 5-40%), and of morphologically intact sperm to 51% in both seasons. Results of S.E.M. showed typical membrane ruptures in the acrosomal region and some sperm with abnormal necks. The proportion of frozen sperm with spontaneous acrosome reaction was higher during winter (86.5 versus 77.0%), suggesting a higher degree of membrane reactivity. Percentages of spermatozoa with denaturated chromatin were minimal and showed minimal differences between fresh and frozen state, stallions or seasons. An additional decondensation treatment with papain and DTE revealed a slightly enhanced number of spermatozoa with denaturable DNA after

  10. Tracking Changes in Coastal and Nearshore Morphology in the Southern Beaufort Sea Using Synthetic Aperture Radar

    NASA Astrophysics Data System (ADS)

    Solomon, S. M.; Fraser, P.; Whalen, D.

    2007-12-01

    Nearshore morphology in the Mackenzie Delta region of the Beaufort Sea is poorly known because much of the region is very shallow (< 2 m) and the water is highly turbid. Synthetic Aperture Radar (SAR) has been used to map nearshore morphology of lakes in Alaska by taking advantage of the ability of radar waves to penetrate freshwater ice. This technique has been extended to the Mackenzie Delta nearshore region where winter ice forms from river water that is sufficiently fresh so as to be transparent at SAR frequencies. SAR allows the delineation of sea ice that freezes to the seabed (bottom-fast ice or BFI). A time series of imagery throughout a winter depicts the progressive growth of areas where BFI occurs and if sea ice thickness is known at the time of imaging, the delineation of BFI zones represents a proxy for bathymetry. Progressive development of BFI was mapped through the winters of 2003-07 and isolated images from other years are available. The nearshore morphology of the region as revealed by BFI mapping is characterized by extensive nearshore shoals that form at the mouths of active distributaries and are separated by wide, slightly deeper embayments. Narrow channels can be seen to transect the shoals both aligned with and orthogonal to the river outflow. Detailed images from thick ice years depict channels fanning out to feed distributary mouth bars. Comparison of images acquired over more than 10 years suggest that shoal migration can exceed 100 m per year and channel incision of the shoals to depths of >5 m has occurred. The BFI imagery suggests that there is sufficient room beneath the sea ice cover to permit river discharge to reach the shelf without requiring extensive networks of sub- ice channels. The distribution of bottomfast ice also constrains discharge during winter and spring. High inflows occurring during winter surges may lift the ice canopy or over flow onto the surface of the ice disrupting transportation networks. Negative surges in

  11. CW-laser-induced morphological changes of a single gold nanoparticle on glass: observation of surface evaporation.

    PubMed

    Setoura, Kenji; Okada, Yudai; Hashimoto, Shuichi

    2014-12-28

    Pulsed-laser heating of colloidal noble-metal nanoparticles in an aqueous solution induces morphological changes such as size reduction. However, the technique suffers disadvantages through polydispersed products. Here, we show that continuous-wave (CW) laser heating of single gold nanoparticles is capable of generating particles of smaller diameters with superb control in terms of exposure time and intensity. We show, based on calculations of particle temperatures under illumination, that surface evaporation below the boiling point of bulk gold occurs, resulting in a gradual diameter decrease in air. In our experiment, a focused illumination of Au NPs through an objective lens of a microscope provided peak-power densities (10(6)-10(7) W cm(-2)) equivalent to that of a typical nanosecond laser. Nevertheless the heating rate under CW laser illumination is much lower than that under pulsed-laser illumination, resulting in better control over nanoparticle heating and related morphological changes. Furthermore, the single-particle study of such heating helps us to clarify the evolution of such changes to a given particle. PMID:25377431

  12. Correlations Between Fluvial Morphologic Changes and Vegetation, and Fluvio-deltaic Behavior on Deltas Using Remote Sensing

    NASA Astrophysics Data System (ADS)

    Felicia, A. L.; Weissmann, G. S.; Scuderi, L. A.; Hartley, A. J.

    2015-12-01

    Large deltas (>30 km in length) provide the majority of sediment to the world's oceans and contain important aquifers and hydrocarbon reservoirs; however, a comprehensive analysis of the geomorphic influence of factors (e.g., tides, groundwater interaction, and upstream discharge and sediment supply) controlling fluvio-deltaic deposition and morphology has not been conducted. To document the geomorphological changes occurring from the apex to the toe of deltas, a database of 84 large modern deltas was compiled. Of these deltas, several were specifically selected to gauge the interplay of tidal, groundwater, and fluvial influence on the modern river channels on these deltas. On these selected deltas, we analyzed the river width and sinuosity with distance downstream from the apex using Shuttle Radar Topography Mission (SRTM) and LANDSAT imagery. Additionally, we analyzed a time-series from the year 2000 to 2015 of interpreted vegetation density using the Normalized Difference Vegetation Index (NDVI). Since vegetation density and type are related to both salinity and groundwater conditions, we are able to observe systematic changes in vegetation across different portions of the delta, depending on the major hydrologic influences in each area (e.g., tidal, fresh groundwater, brackish groundwater, or direct fluvial influence). In this study, we evaluate correlations between fluvial morphologic changes and vegetation density and type, thus helping to improve our understanding of the significance of tides and groundwater on fluvio-deltaic behavior globally.

  13. Ocular gene transfer of active TGF-beta induces changes in anterior segment morphology and elevated IOP in rats.

    PubMed

    Robertson, Jennifer V; Golesic, Elizabeth; Gauldie, Jack; West-Mays, Judith A

    2010-01-01

    Purpose. Transforming growth factor beta (TGF-beta) is known to play a crucial role in wound healing and fibrotic tissue remodeling. A large body of evidence suggests a role for this cytokine in the pathogenesis of glaucoma; however, the mechanisms by which it affects anterior segment morphology are not well understood. Therefore, the purpose of this study was to examine the effects of TGF-beta overexpression on anterior segment morphology and subsequent effects on intraocular pressure. Methods. Adenoviral gene transfer was used to deliver active TGF-beta1 to the rat eye. Measurements of intraocular pressure were taken with a tonometer on days 0, 14, 21, and 29. Histologic analysis was undertaken to examine anterior segment morphology, and markers of matrix deposition and fibrosis were used. Results. Gene transfer of TGF-beta in the anterior segment resulted in the formation of peripheral anterior synechiae (PAS), which consisted of a fibroproliferative region of corneal endothelial cells, matrix accumulation, and decrease in trabecular meshwork expression of alpha-smooth muscle actin. These features were accompanied by ocular hypertension. Conclusions. Gene transfer of TGF-beta into the anterior segment induces aberrant PAS associated with the transition of corneal endothelial cells and subsequent matrix deposition. These features are highly reminiscent of human iridocorneal endothelial (ICE) syndrome. Gene transfer of TGF-beta can, therefore, be used to induce anatomic changes in the anterior segment in a rodent model that result in ocular hypertension. PMID:19696167

  14. Comparison of Morphological and Functional Endothelial Cell Changes after Cataract Surgery: Phacoemulsification Versus Manual Small-Incision Cataract Surgery

    PubMed Central

    Ganekal, Sunil; Nagarajappa, Ashwini

    2014-01-01

    Purpose: To compare the morphological (cell density, coefficient of variation and standard deviation) and functional (central corneal thickness) endothelial changes after phacoemulsification versus manual small-incision cataract surgery (MSICS). Design: Prospective randomized control study. Materials and Methods: In this prospective randomized control study, patients were randomly allocated to undergo phacoemulsification (Group 1, n = 100) or MSICS (Group 2, n = 100) using a random number Table. The patients underwent complete ophthalmic evaluation and specular microscopy preoperatively and at 1and 6 weeks postoperatively. Functional and morphological endothelial evaluation was Noncon ROBO PACHY SP-9000 specular microscope. Phacoemulsification was performed, the chop technique and MSICS, by the viscoexpression technique. Results: The mean difference in central corneal thickness at baseline and 1 week between Group 1 and Group 2 was statistically significant (P = 0.027). However, this difference at baseline when compared to 6 week and 1 week, 6 weeks was not statistically significant (P > 0.05). The difference in mean endothelial cell density between groups at 1 week and 6 weeks was statistically significant (P = 0.016). The mean coefficient of variation and mean standard deviation between groups were not statistically significant (P > 0.05, both comparisons). Conclusion: The central corneal thickness, coefficient of variation, and standard deviation were maintained in both groups indicating that the function and morphology of endothelial cells was not affected despite an initial reduction in endothelial cell number in MSICS. Thus, MSICS remains a safe option in the developing world. PMID:24669147

  15. Morphological and chemical changes of aerosolized E. coli treated with a dielectric barrier discharge.

    PubMed

    Romero-Mangado, Jaione; Nordlund, Dennis; Soberon, Felipe; Deane, Graham; Maughan, Kevin; Sainio, Sami; Singh, Gurusharan; Daniels, Stephen; Saunders, Ian T; Loftus, David; Meyyappan, M; Koehne, Jessica; Gandhiraman, Ram P

    2016-06-01

    This study presents the morphological and chemical modification of the cell structure of aerosolized Escherichia coli treated with a dielectric barrier discharge (DBD). Exposure to DBD results in severe oxidation of the bacteria, leading to the formation of hydroxyl groups and carbonyl groups and a significant reduction in amine functionalities and phosphate groups. Near edge x-ray absorption fine structure (NEXAFS) measurements confirm the presence of additional oxide bonds upon DBD treatment, suggesting oxidation of the outer layer of the cell wall. Electron microscopy images show that the bacteria undergo physical distortion to varying degrees, resulting in deformation of the bacterial structure. The electromagnetic field around the DBD coil causes severe damage to the cell structure, possibly resulting in leakage of vital cellular materials. The oxidation and chemical modification of the bacterial components are evident from the Fourier transform infrared spectroscopy and NEXAFS results. The bacterial reculture experiments confirm inactivation of airborne E. coli upon treating with DBD. PMID:26872580

  16. Microbiota-Induced Changes in Drosophila melanogaster Host Gene Expression and Gut Morphology

    PubMed Central

    Buchon, Nicolas

    2014-01-01

    ABSTRACT To elucidate mechanisms underlying the complex relationships between a host and its microbiota, we used the genetically tractable model Drosophila melanogaster. Consistent with previous studies, the microbiota was simple in composition and diversity. However, analysis of single flies revealed high interfly variability that correlated with differences in feeding. To understand the effects of this simple and variable consortium, we compared the transcriptome of guts from conventionally reared flies to that for their axenically reared counterparts. Our analysis of two wild-type fly lines identified 121 up- and 31 downregulated genes. The majority of these genes were associated with immune responses, tissue homeostasis, gut physiology, and metabolism. By comparing the transcriptomes of young and old flies, we identified temporally responsive genes and showed that the overall impact of microbiota was greater in older flies. In addition, comparison of wild-type gene expression with that of an immune-deficient line revealed that 53% of upregulated genes exerted their effects through the immune deficiency (Imd) pathway. The genes included not only classic immune response genes but also those involved in signaling, gene expression, and metabolism, unveiling new and unexpected connections between immunity and other systems. Given these findings, we further characterized the effects of gut-associated microbes on gut morphology and epithelial architecture. The results showed that the microbiota affected gut morphology through their impacts on epithelial renewal rate, cellular spacing, and the composition of different cell types in the epithelium. Thus, while bacteria in the gut are highly variable, the influence of the microbiota at large has far-reaching effects on host physiology. PMID:24865556

  17. Oxidative Stress Induces Persistent Telomeric DNA Damage Responsible for Nuclear Morphology Change in Mammalian Cells

    PubMed Central

    Coluzzi, Elisa; Colamartino, Monica; Cozzi, Renata; Leone, Stefano; Meneghini, Carlo; O’Callaghan, Nathan; Sgura, Antonella

    2014-01-01

    One main function of telomeres is to maintain chromosome and genome stability. The rate of telomere shortening can be accelerated significantly by chemical and physical environmental agents. Reactive oxygen species are a source of oxidative stress and can produce modified bases (mainly 8-oxoG) and single strand breaks anywhere in the genome. The high incidence of guanine residues in telomeric DNA sequences makes the telomere a preferred target for oxidative damage. Our aim in this work is to evaluate whether chromosome instability induced by oxidative stress is related specifically to telomeric damage. We treated human primary fibroblasts (MRC-5) in vitro with hydrogen peroxide (100 and 200 µM) for 1 hr and collected data at several time points. To evaluate the persistence of oxidative stress-induced DNA damage up to 24 hrs after treatment, we analysed telomeric and genomic oxidative damage by qPCR and a modified comet assay, respectively. The results demonstrate that the genomic damage is completely repaired, while the telomeric oxidative damage persists. The analysis of telomere length reveals a significant telomere shortening 48 hrs after treatment, leading us to hypothesise that residual telomere damage could be responsible for the telomere shortening observed. Considering the influence of telomere length modulation on genomic stability, we quantified abnormal nuclear morphologies (Nucleoplasmic Bridges, Nuclear Buds and Micronuclei) and observed an increase of chromosome instability in the same time frame as telomere shortening. At subsequent times (72 and 96 hrs), we observed a restoration of telomere length and a reduction of chromosome instability, leaving us to conjecture a correlation between telomere shortening/dysfunction and chromosome instability. We can conclude that oxidative base damage leads to abnormal nuclear morphologies and that telomere dysfunction is an important contributor to this effect. PMID:25354277

  18. Monitoring river morphological changes using high resolution multitemporal sar images: a case study on orco river, italy

    NASA Astrophysics Data System (ADS)

    Mitidieri, Francesco; Nicolina Papa, Maria; Ruello, Giuseppe; Amitrano, Donato; Bizzi, Simone; Demarchi, Luca

    2016-04-01

    Improving the knowledge about river processes by applying innovative monitoring techniques is extremely needed to face the challenge of a better river management. In this paper we test the capability of satellite synthetic aperture radar (SAR) images to enrich the monitoring of river geomorphological processes. Multitemporal SAR images provide observations and measurements at high spatial (3 m), and in particular temporal resolution (15 days). This information if properly processed and classified may significantly enrich our ability to monitor the evolution of river morphological phenomena (erosion/deposition, narrowing/widening, riparian vegetation's evolution and interferences with river flow). This is expected to lead to an enhancements in the river management capabilities, in particular as regards the assessment of hydro-morphological river quality, as strongly suggested by European Commission's Water Framework Directive (2000/60/EC). A case study on the Italian River Orco is here presented. The case study has used a set of 100 COSMO-SkyMed stripmap images (from October 2008 to November 2014) from Italian Space Agency. All the data were acquired with medium look angle (almost 30°) and HH polarization, also for increasing the land-water contrast. Calibration, registration and despeckling procedures were applied on the acquired dataset. In particular, the optimal weighting multitemporal De Grandi filter was adopted in order to allow an effective extraction of the water surfaces contour. This method was applied to extract water contours over the entire historical series of SAR datasets available. Thanks to the generated information we were able to monitor the lateral dynamic of the water channels and infer on the evolutions of erosion/deposition phenomena. To this aim, an RGB representation of multitemporal SAR data was implemented. The series of detected river channel morphological changes was then analyzed in the light of the series of discharge measurements in

  19. Particle size distribution and morphological changes in activated carbon-metal oxide hybrid catalysts prepared under different heating conditions.

    PubMed

    Barroso-Bogeat, A; Alexandre-Franco, M; Fernández-González, C; Gómez-Serrano, V

    2016-03-01

    In catalysis processes, activated carbon (AC) and metal oxides (MOs) are widely used either as catalysts or as catalyst supports because of their unique properties. A combination of AC and a MO in a single hybrid material entails changes not only in the composition, microstructure and texture but also in the morphology, which may largely influence the catalytic behaviour of the resulting product. This work is aimed at investigating the modifications in the morphology and particle size distribution (PSD) for AC-MO hybrid catalysts as a result of their preparation under markedly different heating conditions. From a commercial AC and six MO (Al2 O3 , Fe2 O3 , ZnO, SnO2 , TiO2 and WO3 ) precursors, two series of such catalysts are prepared by wet impregnation, oven-drying at 120ºC, and subsequent heat treatment at 200ºC or 850ºC in inert atmosphere. The resulting samples are characterized in terms of their morphology and PSD by scanning electron microscopy and ImageJ processing program. Obtained results indicate that the morphology, PSD and degree of dispersion of the supported catalysts are strongly dependent both on the MO precursor and the heat treatment temperature. With the temperature rise, trends are towards the improvement of crystallinity, the broadening of the PSD and the increase in the average particle size, thus suggesting the involvement of sintering mechanisms. Such effects are more pronounced for the Fe, Sn and W catalysts due to the reduction of the corresponding MOs by AC during the heat treatment at 850ºC. PMID:26457467

  20. Morphological changes in neurons of the hind limb reflex arc during long term immobilization

    NASA Technical Reports Server (NTRS)

    Tkachenko, Z. Y.

    1980-01-01

    Twelve adult rabbits were immobilized for 9 to 31 days, followed by histological study of the nerve processes of lumbar vertebra 7 and sacral vertebra 1, the sciatic nerve and the motor endings of the thigh muscles. In the spinal ganglia, dystrophic changes of increasing severity with immobilization time were found, including pericellular edema, vacuolized neuroplasm, pycnotic changes, cytolysis and destruction. Chromatophilic matter decreased and was partly bleached, and amitotic division occurred. A portion of the sciatic nerve fibers were argentophilic, and some fragmentary decomposition occurred. Considerable dystrophic changes occurred in the motor nerve endings.

  1. Changes in morphology and spatial position of coiled bodies during NGF-induced neuronal differentiation of PC12 cells.

    PubMed

    Janevski, J; Park, P C; De Boni, U

    1997-11-01

    Interphase nuclei are organized into structural and functional domains. The coiled body, a nuclear organelle of unknown function, exhibits cell type-specific changes in number and morphology. Its association with nucleoli and with small nuclear ribonucleo-proteins (snRNPs) indicates that it functions in RNA processing. In cycling cells, coiled bodies are round structures not associated with nucleoli. In contrast, in neurons, they frequently present as nucleolar "caps." To test the hypothesis that neuronal differentiation is accompanied by changes in the spatial association of coiled bodies with nucleoli and in their morphology, PC12 cells were differentiated into a neuronal phenotype with nerve growth factor (NGF) and coiled bodies detected by immunocytochemical localization of p80-coilin and snRNPs. The fraction of cells that showed coiled bodies as nucleolar caps increased from 1.6 +/- 0.9% (mean +/- SEM) in controls to 16.5 +/- 1.6% in NGF-differentiated cultures. The fraction of cells with ring-like coiled bodies increased from 17.2 +/- 5.0% in controls to 57.8 +/- 4.4% in differentiated cells. This was accompanied by a decrease, from 81.2 +/- 5.7% to 25.7 +/- 3.1%, in the fraction of cells with small, round coiled bodies. SnRNPs remained associated with typical coiled bodies and with ring-like coiled bodies during NGF-induced recruitment of snRNPs to the nuclear periphery. Together with the observation that coiled bodies are also present as nucleolar caps in sensory neurons, the results indicate that coiled bodies alter their morphology and increase their association with nucleoli during NGF-induced neuronal differentiation. PMID:9358854

  2. Exposure to non-ionizing radiation provokes changes in rat thyroid morphology and expression of HSP-90.

    PubMed

    Misa-Agustiño, Maria J; Jorge-Mora, Teresa; Jorge-Barreiro, Francisco J; Suarez-Quintanilla, Juan; Moreno-Piquero, Eduardo; Ares-Pena, Francisco J; López-Martín, Elena

    2015-09-01

    Non-ionizing radiation at 2.45 GHz may modify the morphology and expression of genes that codify heat shock proteins (HSP) in the thyroid gland. Diathermy is the therapeutic application of non-ionizing radiation to humans for its beneficial effects in rheumatological and musculo-skeletal pain processes. We used a diathermy model on laboratory rats subjected to maximum exposure in the left front leg, in order to study the effects of radiation on the nearby thyroid tissue. Fifty-six rats were individually exposed once or repeatedly (10 times in two weeks) for 30 min to 2.45 GHz radiation in a commercial chamber at different non-thermal specific absorption rates (SARs), which were calculated using the finite difference time domain technique. We used immunohistochemistry methods to study the expression of HSP-90 and morphological changes in thyroid gland tissues. Ninety minutes after radiation with the highest SAR, the central and peripheral follicles presented increased size and the thickness of the peripheral septa had decreased. Twenty-four hours after radiation, only peripheral follicles radiated at 12 W were found to be smaller. Peripheral follicles increased in size with repeated exposure at 3 W power. Morphological changes in the thyroid tissue may indicate a glandular response to acute or repeated stress from radiation in the hypothalamic-pituitary-thyroid axis. Further research is needed to determine if the effect of this physical agent over time may cause disease in the human thyroid gland. PMID:25649190

  3. Effects of changing channel morphology on vegetation, groundwater, and soil moisture regimes in groundwater dependent ecosystems

    NASA Astrophysics Data System (ADS)

    Loheide, S. P.; Booth, E. G.

    2008-12-01

    Channel incision and excessive floodplain sedimentation are major causes of riparian degradation across the country. Though the causes and consequences of these processes vary significantly, the resulting morphology in both cases is steep streambanks and a stream that is less connected with the floodplain. A case study from semi-arid, wet meadows with snow-melt driven hydrology in the Sierra Nevada of CA will be compared with one from a riparian wet prairie in the humid environment of the Driftless Area of southern Wisconsin. In the mountain meadows, 80 years of logging and overgrazing led to more flashy runoff and downcutting of the stream. This led to drainage of groundwater from the meadow and a shift in vegetation composition from sedges and rushes to dryland grasses and sagebrush in this groundwater dependent ecosystem. In the Driftless Area of WI, the introduction of agricultural practices by European settlers in the 1830s resulted in severe erosion from the cropped areas in the uplands. This sediment was transported to the stream valleys where it was deposited on the floodplain, raising this surface relative to the streambed. As a result, the water table is at a greater depth from this elevated land surface. In this ecosystem, the vegetation has shifted from wet prairie and sedge meadow communities to grasses and lowland forests dominated by box elder trees. The geomorphic result at both sites was a channel bounded by tall banks with reduced hydrologic connectivity with the floodplain. In both cases, the slope of the water table towards the stream is greater than the topographic slope across the riparian zone and the greatest depth to the water table is found adjacent to the channel. Transects exhibit a decreasing trend in soil moisture with increasing variability toward the channel. Remotely sensed imagery shows trends of drier vegetation communities adjacent to channels and wetter vegetation communities toward the margin of the riparian zones. Coupled

  4. Binge Drinking of Ethanol during Adolescence Induces Oxidative Damage and Morphological Changes in Salivary Glands of Female Rats.

    PubMed

    Fagundes, Nathalia Carolina Fernandes; Fernandes, Luanna Melo Pereira; Paraense, Ricardo Sousa de Oliveira; de Farias-Junior, Paulo Mecenas Alves; Teixeira, Francisco Bruno; Alves-Junior, Sergio Melo; Pinheiro, João de Jesus Viana; Crespo-López, Maria Elena; Maia, Cristiane Socorro Ferraz; Lima, Rafael Rodrigues

    2016-01-01

    This study investigates morphological and biochemistry effects of binge ethanol consumption in parotid (PG) and submandibular (SG) salivary glands of rats from adolescence to adulthood. Female Wistar rats (n = 26) received ethanol at 3 g/kg/day (20% w/v) for 3 consecutive days/week from the 35th until the 62nd day of life. Animals were treated in two periods: 1 week (G1) and 4 weeks (G2), with a control (treated with distilled water) and an ethanol group to each period. In morphological analysis, morphometric and immunohistochemistry evaluation for smooth muscle actin (αSMA), cytokeratin-18 (CK-18), and vimentin (VIM) were made. Biochemical changes were analyzed by concentration of nitrites and levels of malondialdehyde (MDA). The difference between groups in each analysis was evaluated by Mann-Whitney U test or Student's t-test (p ≤ 0.05). PG showed, at one week of ethanol exposure, lower CK-18 and α-SMA expression, as well as MDA levels. After four weeks, lower CK-18 and higher MDA levels were observed in PG exposed to ethanol, in comparison to control group. SG showed lower α-SMA expression after 1 and 4 weeks of ethanol exposure as well as higher MDA levels after 1 week. Ethanol binge consumption during adolescence promotes tissue and biochemical changes with only one-week binge in acinar and myoepithelial PG cells. PMID:27579155

  5. Decadal morphological evolution of the Yangtze Estuary in response to river input changes and estuarine engineering projects

    NASA Astrophysics Data System (ADS)

    Luan, Hua Long; Ding, Ping Xing; Wang, Zheng Bing; Ge, Jian Zhong; Yang, Shi Lun

    2016-07-01

    The Yangtze Estuary in China has been intensively influenced by human activities including altered river and sediment discharges in its catchment and local engineering projects in the estuary over the past half century. River sediment discharge has significantly decreased since the 1980s because of upstream dam construction and water-soil conservation. We analyzed bathymetric data from the Yangtze Estuary between 1958 and 2010 and divided the entire estuary into two sections: inner estuary and mouth bar area. The deposition and erosion pattern exhibited strong temporal and spatial variations. The inner estuary and mouth bar area underwent different changes. The inner estuary was altered from sedimentation to erosion primarily at an intermediate depth (5-15 m) along with river sediment decline. In contrast, the mouth bar area showed continued accretion throughout the study period. The frequent river floods during the 1990s and simultaneously decreasing river sediment probably induced the peak erosion of the inner estuary in 1986-1997. We conclude that both sediment discharge and river flood events played important roles in the decadal morphological evolution of the Yangtze Estuary. Regarding the dredged sediment, the highest net accretion rate occurred in the North Passage where jetties and groins were constructed to regulate the navigation channel in 1997-2010. In this period, the jetties induced enhanced deposition at the East Hengsha Mudflat and the high accretion rate within the mouth bar area was maintained. The impacts of estuarine engineering projects on morphological change extended beyond their sites.

  6. Optical coherence tomography and confocal fluorescence microscopy as a combined method for studying morphological changes in lung dynamics

    NASA Astrophysics Data System (ADS)

    Gaertner, Maria; Cimalla, Peter; Knels, Lilla; Meissner, Sven; Schnabel, Christian; Kuebler, Wolfgang M.; Koch, Edmund

    2011-03-01

    Acute lung injury (ALI) is a severe pulmonary disease leading to hypoxemia accompanied by a reduced compliance and partial edema of the lung. Most of the patients have to be ventilated to compensate for the lack of oxygen. The treatment is strongly connected with ventilator induced lung injury (VILI), which is believed to introduce further stress to the lung and changes in its elastic performance. A thorough understanding of the organs micro-structure is crucial to gain more insight into the course of the disease. Due to backscattering of near-infrared light, detailed description of lung morphology can be obtained using optical coherence tomography (OCT), a non-invasive, non-contact, high resolution and fast three-dimensional imaging technique. One of its drawbacks lies in the non-specificity of light distribution in relation to defined substances, like elastic biomolecules. Using fluorescence detection, these chemical components can be visualized by introducing specifically binding fluorophores. This study presents a combined setup for studying alveolar compliance depending on volume changes and elastic fiber distributions. Simultaneously acquired OCT and confocal fluorescence images allow an entire view into morphological rearrangements during ventilation for an ex vivo mouse model using continuous pulmonary airway pressure at different values.

  7. Binge Drinking of Ethanol during Adolescence Induces Oxidative Damage and Morphological Changes in Salivary Glands of Female Rats

    PubMed Central

    Fagundes, Nathalia Carolina Fernandes; Fernandes, Luanna Melo Pereira; Paraense, Ricardo Sousa de Oliveira; Teixeira, Francisco Bruno; Alves-Junior, Sergio Melo; Pinheiro, João de Jesus Viana; Crespo-López, Maria Elena

    2016-01-01

    This study investigates morphological and biochemistry effects of binge ethanol consumption in parotid (PG) and submandibular (SG) salivary glands of rats from adolescence to adulthood. Female Wistar rats (n = 26) received ethanol at 3 g/kg/day (20% w/v) for 3 consecutive days/week from the 35th until the 62nd day of life. Animals were treated in two periods: 1 week (G1) and 4 weeks (G2), with a control (treated with distilled water) and an ethanol group to each period. In morphological analysis, morphometric and immunohistochemistry evaluation for smooth muscle actin (αSMA), cytokeratin-18 (CK-18), and vimentin (VIM) were made. Biochemical changes were analyzed by concentration of nitrites and levels of malondialdehyde (MDA). The difference between groups in each analysis was evaluated by Mann-Whitney U test or Student's t-test (p ≤ 0.05). PG showed, at one week of ethanol exposure, lower CK-18 and α-SMA expression, as well as MDA levels. After four weeks, lower CK-18 and higher MDA levels were observed in PG exposed to ethanol, in comparison to control group. SG showed lower α-SMA expression after 1 and 4 weeks of ethanol exposure as well as higher MDA levels after 1 week. Ethanol binge consumption during adolescence promotes tissue and biochemical changes with only one-week binge in acinar and myoepithelial PG cells. PMID:27579155

  8. Magnetic resonance imaging of morphological and functional changes of the uterus induced by sacral surface electrical stimulation.

    PubMed

    Ogura, Takahide; Murakami, Takashi; Ozawa, Yuka; Seki, Kazunori; Handa, Yasunobu

    2006-01-01

    The purpose of this study is to examine the morphological and kinematical changes of the uterus induced by electrical stimulation applied to the skin just above the second and fourth posterior sacral foramens (sacral surface electrical stimulation [ssES]) in 26 healthy subjects. Out of them, eight subjects who had severe pain subjectively during every menstruation received ssES just in menstruation. Morphological and functional changes of the uterus were examined by using T2-weighted magnetic resonance (MR) imaging and T1-weighted MR cinematography, respectively. Cyclic electrical stimulation for 15 min with 5 sec ON and 5 sec OFF was applied just before MR scanning. A decrease in thickness of the muscular layer of the uterus was observed in every subject after ssES for 15 min and was significant as compared with the thickness before ssES. Periodic uterine movement during menstruation was observed in the subjects with severe menstrual pain in MR cine and the power spectrum analysis of the movement showed a marked decrease in peak power and frequency after ssES treatment. We conclude that ssES causes a reduction of static muscle tension of the uterus in all menstrual cycle periods and suppression of uterine peristalsis during menstruation in the subjects with severe menstrual pain. Possible neural mechanisms for these static and dynamic effects of ssES on the uterus at spinal level are discussed. PMID:16340175

  9. Dramatic beach and nearshore morphological changes due to extreme flooding at a wave-dominated river mouth (Invited)

    NASA Astrophysics Data System (ADS)

    Barnard, P. L.; Warrick, J. A.

    2009-12-01

    Direct observations of major floods which input large volumes of sediment into littoral systems generally are rare due to the scarcity of large events and the difficulty of obtaining appropriate data. To understand the importance of infrequent, high-discharge river floods on the long-term morphodynamics of a coastal system, we combine 16 years of pre-flood survey data with three years of post-flood data to characterize morphologic changes at a wave-dominated river mouth. This study provides in-depth morphological analysis of coastal response to an extremely rare flooding event; the highest discharge on record for the Santa Clara River (CA, USA) which occurred in January 2005. This event injected ~5 million m3 of littoral-grade sediment into the Santa Barbara Littoral Cell (SBLC), producing rapid and extreme beach and nearshore morphologic evolution. The sediment load produced by the event is an order of magnitude larger than both the average annual river loads and the annual alongshore littoral transport in this portion of the SBLC. Over 170 m of local shoreline (mean high water (MHW)) progradation was observed as result of the flood, followed by 3 years of rapid local shoreline retreat. Linear regression-determined shoreline change rates of up to -45 m a-1 were observed on the subaerial beach (MHW) and -114 m a-1 on the submarine delta (6 m isobath). Starting approximately 1 km downdrift of the river mouth, shoreline progradation persisted throughout the three-year post-flood monitoring period, with rates of up to +19 m a-1. Post-flood bathymetric surveys show nearshore (0 to 12 m depth) erosion on the delta exceeding 400 m3/m a-1, more than an order of magnitude higher than mean seasonal cross-shore sediment transport rates in the region. Changes were not constant with depth, however; sediment accumulation and subsequent erosion on the delta were greatest at -5 to -8 m, and accretion in downdrift areas was greatest above -2 m. Simple “one-line” shoreline

  10. Statistics of Language Morphology Change: From Biconsonantal Hunters to Triconsonantal Farmers

    PubMed Central

    Agmon, Noam; Bloch, Yigal

    2013-01-01

    Linguistic evolution mirrors cultural evolution, of which one of the most decisive steps was the "agricultural revolution" that occurred 11,000 years ago in W. Asia. Traditional comparative historical linguistics becomes inaccurate for time depths greater than, say, 10 kyr. Therefore it is difficult to determine whether decisive events in human prehistory have had an observable impact on human language. Here we supplement the traditional methodology with independent statistical measures showing that following the transition to agriculture, languages of W. Asia underwent a transition from biconsonantal (2c) to triconsonantal (3c) morphology. Two independent proofs for this are provided. Firstly the reconstructed Proto-Semitic fire and hunting lexicons are predominantly 2c, whereas the farming lexicon is almost exclusively 3c in structure. Secondly, while Biblical verbs show the usual Zipf exponent of about 1, their 2c subset exhibits a larger exponent. After the 2c > 3c transition, this could arise from a faster decay in the frequency of use of the less common 2c verbs. Using an established frequency-dependent word replacement rate, we calculate that the observed increase in the Zipf exponent has occurred over the 7,500 years predating Biblical Hebrew namely, starting with the transition to agriculture. PMID:24367613

  11. Morphology Change of C60 Islands on Organic Crystals Observed by Atomic Force Microscopy.

    PubMed

    Freund, Sara; Hinaut, Antoine; Pawlak, Rémy; Liu, Shi-Xia; Decurtins, Silvio; Meyer, Ernst; Glatzel, Thilo

    2016-06-28

    Organic-organic heterojunctions are nowadays highly regarded materials for light-emitting diodes, field-effect transistors, and photovoltaic cells with the prospect of designing low-cost, flexible, and efficient electronic devices.1-3 However, the key parameter of optimized heterojunctions relies on the choice of the molecular compounds as well as on the morphology of the organic-organic interface,4 which thus requires fundamental studies. In this work, we investigated the deposition of C60 molecules at room temperature on an organic layer compound, the salt bis(benzylammonium)bis(oxalato)cupurate(II), by means of noncontact atomic force microscopy. Three-dimensional molecular islands of C60 having either triangular or hexagonal shapes are formed on the substrate following a "Volmer-Weber" type of growth. We demonstrate the dynamical reshaping of those C60 nanostructures under the local action of the AFM tip at room temperature. The dissipated energy is about 75 meV and can be interpreted as the activation energy required for this migration process. PMID:27219352

  12. Morphological and chemical changes of aerosolized E. coli treated with a dielectric barrier discharge

    DOE PAGESBeta

    Romero-Mangado, Jaione; Nordlund, Dennis; Soberon, Felipe; Deane, Graham; Maughan, Kevin; Sainio, Sami; Singh, Gurusharan; Daniels, Stephen; Saunders, Ian T.; Loftus, David; et al

    2016-02-12

    This paper presents the morphological and chemical modification of the cell structure of aerosolized Escherichia coli treated with a dielectric barrier discharge (DBD). Exposure to DBD results in severe oxidation of the bacteria, leading to the formation of hydroxyl groups and carbonyl groups and a significant reduction in amine functionalities and phosphate groups. Near edge x-ray absorption fine structure(NEXAFS) measurements confirm the presence of additional oxide bonds upon DBD treatment, suggesting oxidation of the outer layer of the cell wall. Electron microscopy images show that the bacteria undergo physical distortion to varying degrees, resulting in deformation of the bacterial structure.more » The electromagnetic field around the DBD coil causes severe damage to the cell structure, possibly resulting in leakage of vital cellular materials. The oxidation and chemical modification of the bacterial components are evident from the Fourier transform infrared spectroscopy and NEXAFS results. The bacterial reculture experiments confirm inactivation of airborne E. coli upon treating with DBD.« less

  13. Experimental and numerical characterization of floc morphology: role of changing hydraulic retention time under flocculation mechanisms.

    PubMed

    Nan, Jun; Yao, Meng; Chen, Ting; Wang, Zhenbei; Li, Qinggui; Zhan, Dan

    2016-02-01

    The formation, breakage, and re-growth of flocs were investigated by using modified flocculation tests and numerical simulation to explore the evolution of floc morphology for different hydraulic retention times. The shorter the aggregation time was, the smaller the flocs produced for the same hydraulic conditions were. Another interesting discovery was that broken flocs that formed in shorter aggregation time had the capacity to completely recover, whereas those formed in a longer amount of time had rather worse reversibility of broken flocs. With the addition of the maximum motion step in the representative two-dimensional diffusion-limited aggregation (DLA) model, there was a transition for flocs from isotropic to anisotropic as the maximum motion step increased. The strength of flocs was mainly affected by the distribution of particles near the aggregated core rather than distant particles. A simplified breakage model, which found that broken flocs provided more chances for diffused particles to access the inner parts of flocs and to be uniformly packed around the aggregated core, was first proposed. Moreover, an important result showed that the floc fragments formed with a larger value of the maximum motion step had more growing sites than did those with a smaller msa value, which was a benefit of following the re-forming procedure. PMID:26490940

  14. Observations of aerosol light scattering, absorption, and particle morphology changes as a function of relative humidity

    NASA Astrophysics Data System (ADS)

    Arnott, W. P.; Lewis, K.; Paredes-Miranda, G.; Winter, S.; Day, D.; Chakrabarty, R.; Moosmuller, H.; Jimenez, J. L.; Ulbrich, I.; Huffman, A.; Onasch, T.; Trimborn, A.; Kreidenweis, S.; Carrico, C.; Wold, C.; Lincoln, E.; Freeborn, P.; Hao, W.; McMeeking, G.

    2006-12-01

    A very interesting case of smoke aerosol with very low single scattering albedo, yet very large hygroscopic growth for scattering is presented. Several samples of chamise (Adenostoma fasciculatum), a common and often dominant species in California chaparral, were recently burned at the USFS Fire Science Laboratory in Missoula Montana, and aerosol optics and chemistry were observed, along with humidity-dependent light scattering, absorption, and particle morphology. Photoacoustic measurements of light absorption by two instruments at 870 nm, one on the dry channel, one on the humidified channel, showed strong reduction of aerosol light absorption with RH above 65 percent, and yet a strong increase in light scattering was observed both at 870 nm and 550 nm with nephelometers. Multispectral measurements of aerosol light absorption indicated an Angstrom coefficient for absorption near unity for the aerosols from chamise combustion. It is argued that the hygroscopic growth of scattering is due to uptake of water by the sulfur bearing aerosol. Furthermore, the reduction of aerosol light absorption is argued to be due to the collapse of chain aggregate aerosol as the RH increases wherein the interior of aerosol does no longer contribute to absorption. Implications for biomass burning in general are that humidity processing of aerosols from this source and others like it tends to substantially increase its single scattering albedo, probably in a non-reversible manner. The chemical pathway to hygroscopicity will be addressed.

  15. Salinity induced anatomical and morphological changes in Chloris gayana Kunth roots.

    PubMed

    Céccoli, Gabriel; Ramos, Julio C; Ortega, Leandro I; Acosta, Juan M; Perreta, Mariel G

    2011-04-01

    Chloris gayana Kunth is a grass species valuable as forage which was introduced into Argentina to be used as pasture in saline soils of subtropical and warm-temperate zones, given its good adaptability to drought, salinity and mild freezing. However, its tolerance varies according to the cultivar. In tetraploid cultivars, important reductions in yield have been observed. Here, a study of the variations produced on the root and stem system by salinity at different NaCl concentrations (0, 150 and 250 mM) was performed in the Boma cultivar, with the aim of determining the anatomical and morphological alterations produced by the salt excess. Plants cultivated with the highest level of salinity showed, in the whole, significant differences in the measured variables. A diminution in absolute values of the variables and a major reduction in vascular tissue dimensions were observed, which suggests that the lack of tolerance to salt stress could be related to a deficient adaptation to absorb and transport water and nutrients from the roots. PMID:21667667

  16. Morphological change of the acrosome on motile bovine spermatozoa due to storage at 4 degrees C.

    PubMed

    Aalseth, E P; Saacke, R G

    1985-07-01

    Swelling of the apical ridge and anterior acrosome of motile bovine spermatozoa was observed during in-vitro storage using differential interference-contrast optics. This morphological alteration is different from that described as the false acrosome reaction on immotile spermatozoa, apparent in ageing semen samples and which has been associated with cell death. In this study, transmission electron microscopy revealed that the apical ridge acrosomal matrix was extended into complex folds and/or projections. Acrosomal and plasma membrane integrity was retained. Storing spermatozoa (1500 X 10(6)/ml) in seminal plasma at 4 degrees C for 1 day was most conducive to the swelling of the apical ridge. Replacing seminal plasma with egg yolk-citrate inhibited swelling. However, incubating semen at 37 degrees C in egg yolk-Tris-fructose extender (25 X 10(6) spermatozoa/ml) after storage in egg yolk-citrate at 4 degrees C for greater than or equal to 3 days restored the swelling characteristic. PMID:3900381

  17. On the relationship between the energetic particle flux morphology and the change in the magnetic field magnitude during substorms

    NASA Technical Reports Server (NTRS)

    Lopez, R. E.; Lui, A. T. Y.; Sibeck, D. G.; Takahashi, K.; Mcentire, R. W.

    1989-01-01

    The relationship between the morphology of energetic particle substorm injections and the change in the magnetic field magnitude over the course of the event is examined. Using the statistical relationships between the magnetic field during the growth phase and the change in the field magnitude during substorms calculated by Lopez et al. (1988), a limited number of dispersionless ion injections observed by AMPTE CCE are selected. It is argued that this limited set is representative of a large set of events and that the conclusions drawn from examining those events are valid for substorms in general in the inner magnetosphere. It is demonstrated that in an event when CCE directly observed the disruption of the current sheet, the particle and field data show that the region of particle acceleration was highly turbulent and was temporally, and perhaps spatially, limited and that the high fluxes of energetic particles are qualitatively associated with intense inductive electric fields.

  18. The response of the HMX-based material PBXN-9 to thermal insults: thermal decomposition kinetics and morphological changes

    SciTech Connect

    Glascoe, E A; Hsu, P C; Springer, H K; DeHaven, M R; Tan, N; Turner, H C

    2010-12-10

    PBXN-9, an HMX-formulation, is thermally damaged and thermally decomposed in order to determine the morphological changes and decomposition kinetics that occur in the material after mild to moderate heating. The material and its constituents were decomposed using standard thermal analysis techniques (DSC and TGA) and the decomposition kinetics are reported using different kinetic models. Pressed parts and prill were thermally damaged, i.e. heated to temperatures that resulted in material changes but did not result in significant decomposition or explosion, and analyzed. In general, the thermally damaged samples showed a significant increase in porosity and decrease in density and a small amount of weight loss. These PBXN-9 samples appear to sustain more thermal damage than similar HMX-Viton A formulations and the most likely reasons are the decomposition/evaporation of a volatile plasticizer and a polymorphic transition of the HMX from {beta} to {delta} phase.

  19. The Morphology of the Proximal Femoral Canal Continues to Change in the Very Elderly: Implications for Total Hip Arthroplasty.

    PubMed

    Boymans, Tim A E J; Heyligers, Ide C; Grimm, Bernd

    2015-12-01

    A shape mismatch between cementless stems and the femoral canal of very elderly patients could partly explain the inferior performance of cementless compared to cemented stems in this age group. Influences of age and gender on canal morphology were investigated by measuring coronal/sagittal dimensions on CT-scans of subjects ≥80 years old (n = 117) and subjects < 80 years old (n = 51). Absolute canal dimensions like width were larger in octogenarians than in younger subjects. These differences were larger in the sagittal plane than in the coronal plane (P < 0.001). Canal flaring changed asymmetrically with increased medial and less lateral flaring in octogenarians. Age-related changes were mainly observed in females and should be taken into consideration for implant design, selection and implantation in octogenarians. PMID:26187385

  20. [Specific molecular and morphological changes in cardiomyocytes of hibernating ground squirrels in different periods of annual cycle].

    PubMed

    Karaduleva, E V; Santalova, I M; Zakharova, N M

    2014-01-01

    Structural and molecular changes in cardiomyocytes of hibernating ground squirrels in different periods of the annual cycle were analyzed by means of electron microscopy and polymerase chain reaction. Morphological analysis showed an increase in relative area of sarcoplasmic reticulum in cardiac muscle of ground squirrels preparing to torpor compared to active summer animals. The size of sarcoplasmic reticulum in cardiomyocytes of torpid animals was reliably less than in any other condition of ground squirrels in the annual cycle. The results of molecular analysis showed the decrease in sarcoplasmic reticulum Ca(2+)-ATPase gene (SERCA2a) expression .at all stages of hibernation process and also in periods of autumn activity compared to control mRNA level in active summer animals. The revealed season changes in structure of sarcoplasmic reticulum and sarcoplasmic reticulum Ca(2+)-ATPase gene expression are discussed in regard to adaptation of ground squirrels to hibernation. PMID:25730975

  1. Physicochemical, morphological, thermal and IR spectral changes in the properties of waxy rice starch modified with vinyl acetate.

    PubMed

    Kalita, Dipankar; Kaushik, Neelima; Mahanta, Charu L

    2014-10-01

    Waxy rice starch was modified with vinyl acetate at levels of 4, 6, 8, and 10 % with degree of substitution of 0.021, 0.023, 0.032 and 0.056. The modified starches were studied for physicochemical, morphological, thermal and infra red spectral properties. Waxy starch acetates had high water holding capacity and did not sediment. Scanning electron microscopy revealed surface damage of the granules and their fusion. X ray diffractography showed that crystalline peak intensity had increased on acetylation. Differential scanning calorimetry studies showed changes in thermal properties. While gelatinization temperatures of modified starches were higher than the native starch, their transition enthalpies were lower than the native starch. IR spectra of the starch acetates did not show the peak typical for acetyl group. Thus, modification of waxy rice starch with vinyl acetate caused changes in the starch properties. The high water holding capacity of starch acetates can be exploited for specific applications. PMID:25328227

  2. Bryozoans as indicators of global change: predictable shifts in morphology and carbonate mineralogy in response to warming and ocean acidification

    NASA Astrophysics Data System (ADS)

    Swezey, D. S.; Bean, J. R.; Ninokawa, A. T.; Sanford, E.

    2014-12-01

    Recent studies have documented variation in skeletal structure and carbonate mineralogy across a broad range of marine invertebrate taxa. Intraspecific changes in growth, morphology, and carbonate composition may occur in response to local and global changes in temperature, carbonate saturation state, and nutrient availability. Recurring upwelling along the west coast of the United States creates an alongshore mosaic of Ocean Acidification (OA), which may induce plastic responses and/or select for adaptive skeletal construction that can withstand pCO2 and temperature changes. Calcifying bryozoans provide a unique study system for investigating carbonate precipitation under variable conditions. Using a newly constructed flow-through CO2 control apparatus, we tested whether three laboratory-reared populations of the bryozoans Membranipora serrilamella, M. tuberculata and Celleporella cornuta showed differences in growth, calcification, and skeletal composition in response to simulated future OA conditions. Under elevated pCO2 (1200 μatm), bryozoans showed no significant differences in growth rate (new zooids added) compared to clones reared under current atmospheric values. However, C. cornuta colonies raised under high CO2 were significantly lighter, with less carbonate per zooid compared to colonies grown in present-day conditions (400 μatm). Scanning electron microscopy revealed that elevated pCO2 led to dissolution of bryozoan skeletons, which did not occur at 400 μatm. Structural changes in M. tuberculata and C. cornuta colonies may be related to the dissolution of high magnesium calcite skeletal components. Analyses of bryozoan morphological responses along with environmental proxies (δ13C, δ18O, and Mg/Ca ratios) could yield high resolution records of temperature and pH, which could be used to help reconstruct environmental variation along the California coast.

  3. Morphological analysis of GeTe in inline phase change switches

    SciTech Connect

    King, Matthew R.; El-Hinnawy, Nabil; Salmon, Mike; Gu, Jitty; Wagner, Brian P.; Jones, Evan B.; Howell, Robert S.; Nichols, Doyle T.; Young, Robert M.; Borodulin, Pavel

    2015-09-07

    Crystallization and amorphization phenomena in indirectly heated phase change material-based devices were investigated. Scanning transmission electron microscopy was utilized to explore GeTe phase transition processes in the context of the unique inline phase change switch (IPCS) architecture. A monolithically integrated thin film heating element successfully converted GeTe to ON and OFF states. Device cycling prompted the formation of an active area which sustains the majority of structural changes during pulsing. A transition region on both sides of the active area consisting of polycrystalline GeTe and small nuclei (<15 nm) in an amorphous matrix was also observed. The switching mechanism, determined by variations in pulsing parameters, was shown to be predominantly growth-driven. A preliminary model for crystallization and amorphization in IPCS devices is presented.

  4. Morphological analysis of GeTe in inline phase change switches

    NASA Astrophysics Data System (ADS)

    King, Matthew R.; El-Hinnawy, Nabil; Salmon, Mike; Gu, Jitty; Wagner, Brian P.; Jones, Evan B.; Borodulin, Pavel; Howell, Robert S.; Nichols, Doyle T.; Young, Robert M.

    2015-09-01

    Crystallization and amorphization phenomena in indirectly heated phase change material-based devices were investigated. Scanning transmission electron microscopy was utilized to explore GeTe phase transition processes in the context of the unique inline phase change switch (IPCS) architecture. A monolithically integrated thin film heating element successfully converted GeTe to ON and OFF states. Device cycling prompted the formation of an active area which sustains the majority of structural changes during pulsing. A transition region on both sides of the active area consisting of polycrystalline GeTe and small nuclei (<15 nm) in an amorphous matrix was also observed. The switching mechanism, determined by variations in pulsing parameters, was shown to be predominantly growth-driven. A preliminary model for crystallization and amorphization in IPCS devices is presented.

  5. Progressive changes in the morphology of fluvial terraces and scarps along the Rappahannock River, Virginia.

    USGS Publications Warehouse

    Colman, Steven M.

    1983-01-01

    Progressive geomorphic changes in the flight of fluvial terraces along the Rappahannock River, Virginia, provide a framework for analysing the effect of time on landforms. Indices of terrace preservation, especially drainage densities and area to perimeter ratios, show systematic changes with terrace age. Higher scarps tend to have steeper slopes and, for a given scarp height, older scarps tend to have gentler slopes. Depositional features such as bars and channels with 1-3m of relief are preserved on terraces on the order of 105 yr old.-from Author

  6. Age-specific forced polymorphism: implications of ontogenetic changes in morphology for male mating tactics.

    PubMed

    Irschick, Duncan J; Lailvaux, Simon P

    2006-01-01

    Age-specific forced polymorphism is the presence of two or more distinct phenotypes (here we consider only males) that occur in separate sexually mature age groups (e.g., horns in older males but not younger males). The life-stage morph maturation hypothesis posits that all younger males that possess a particular structure can transform into older males with a different structure, most likely via the influence of hormones. The life-stage morph selection hypothesis posits that polymorphism is due to intense selection resulting in a highly nonrandom sample of younger males surviving to become older males, thus leading to different mean phenotypes in different age groups. We conducted an extensive review of literature from the past 20 years (1983-2003) for cases of age-specific forced polymorphism. Overall, we found only a few cases that fit our criteria of age-specific forced polymorphism, and we argue that most (e.g., orangutans, elephant seals) have likely arisen via the life-stage morph maturation mechanism, but we also present several examples (e.g., green anole lizards) that appear to be candidates for life-stage morph selection. However, none of the reviewed studies provided enough information (e.g., age of morphs, growth patterns of the morphological structure) to definitively invoke either of the two mechanisms. We suggest that age-specific forced polymorphism is more common than reflected in this review and that future studies should gather demographic and laboratory data that will directly compare the life-stage morph maturation and life-stage morph selection hypotheses. PMID:16380929

  7. Surface morphology changes of polymer membrane and carbon paste sertraline sensors.

    PubMed

    Khater, M M; Hassib, H B; Issa, Y M; Mohammed, S H

    2015-03-01

    Polymer membrane and chemically modified carbon paste (CMCP) sensors for determination of sertraline HCl (Ser-Cl) incorporating sertraline tetraphenylborate (Ser-TPB) as an electro-active material were constructed. They showed a rapid and linear response for Ser-ion over the concentration range 0.01-10.00 mmol L(-1). The limits of detection were 2.80 and 9.55 μmol L(-1), and Nernastian slopes were 56.60, 59.60 mV decade(-1) for membrane and CMCP sensors for batch method. In flow injection analysis (FIA), the electrodes revealed comparatively good selectivity for Ser-ion with regard to a wide variety of different cations, sugars, and amino acids. The addition of different anionic additives, namely sodium tetraphenylborate (NaTPB), potassium tetraphenylborate (KTPB), potassium tetrakis[3,5-bis-(triflouromethyl)phenyl]borate (KTFMPB), and sodium tetrakis[3,5-bis(trifluoro-methyl)phenyl]borate (NaTFMPB), to the prepared mixture improved their response characteristics. The surface morphologies of membrane films containing PVC only (blank), plasticizer+PVC, Ser-TPB+plasticizer+PVC, and Ser-TPB +plasticizer+PVC+additive were studied using scanning and atomic force electron microscopes. These sensors had been used in the potentiometric titration of Ser-ion against NaTPB. Standard addition method for the pure raw material and some of its pharmaceutical tablets was used for Ser-Cl determination. The obtained results were tested for their repeatability and reproducibility and were statistically treated by F- and t- tests. PMID:25618706

  8. Adaptive responses of mitochondria to mild copper deprivation involve changes in morphology, OXPHOS remodeling and bioenergetics.

    PubMed

    Ruiz, Lina María; Jensen, Erik L; Bustos, Rodrigo I; Argüelloa, Graciela; Gutierrez-Garcia, Ricardo; González, Mauricio; Hernández, Claudia; Paredes, Rodolfo; Simon, Felipe; Riedel, Claudia; Ferrick, David; Elorza, Alvaro A

    2014-05-01

    Copper is an essential cofactor of complex IV of the electron transfer chain, and it is directly involved in the generation of mitochondrial membrane potential. Its deficiency induces the formation of ROS, large mitochondria and anemia. Thus, there is a connection between copper metabolism and bioenergetics, mitochondrial dynamics and erythropoiesis. Copper depletion might end in cellular apoptosis or necrosis. However, before entering into those irreversible processes, mitochondria may execute a series of adaptive responses. Mitochondrial adaptive responses (MAR) may involve multiple and diverse mechanisms for preserving cell life, such as mitochondrial dynamics, OXPHOS remodeling and bioenergetics output. In this study, a mild copper deficiency was produced in an animal model through intraperitoneal injections of bathocuproine disulfonate in order to study the MAR. Under these conditions, a new type of mitochondrial morphology was discovered in the liver. Termed the "butternut squash" mitochondria, it coexisted with normal and swollen mitochondria. Western blot analyses of mitochondrial dynamics proteins showed an up-regulation of MFN-2 and OPA1 fusion proteins. Furthermore, isolated liver mitochondria displayed OXPHOS remodeling through a decrease in supercomplex activity with a concomitant increase at an individual level of complexes I and IV, higher respiratory rates at complex I and II levels, higher oligomycin-insensitive respiration, and lower respiratory control ratio values when compared to the control group. As expected, total ATP and ATP/ADP values were not significantly different, since animal's health was not compromised. As a whole, these results describe a compensatory and adaptive response of metabolism and bioenergetics under copper deprivation. PMID:24446197

  9. Environmental and morphological changes around the Maritime Maya site Vista Alegre.

    NASA Astrophysics Data System (ADS)

    Jaijel, Roy; Goodman, Beverly; Glover, Jeffrey; Beddows, Patricia; Carter, Alice; Smith, Derek; Rissolo, Dominique; Ben Avraham, Zvi

    2016-04-01

    The untold story of the Maritime Maya from the ancient port site Vista Alegre, is being written for the first time using a multidisciplinary effort that aims to reconstruct the environmental and morphological history of the site. Vista Alegre is located on the north-eastern tip of the Yucatan peninsula, on the ancient Maritime Maya trade routes. This strategic point between the Caribbean Sea and the Gulf of Mexico, offers an ideal setting for this kind of research, which will add to the general Maritime Maya history. The multidisciplinary effort is part of a larger project called "Costa Escodida". The project's main goals are to learn how the ancient inhabitants adapted to the environment, and to understand how this coastal site was integrated into broader maritime trade routes. The portion of the research presented here concentrates on the sites geomorphology and climate during the past 2-3000 years through the multiproxy analysis of marine sediment core and surface samples combined with archaeological data. This study aids our understanding of the site's possible functions, the environmental challenges the local inhabits contended with, and the identification of ancient harboring locations. The site was inhabited from the 9th century B.C until the mid 16th century A.D., with an apparent two century abandonment phase from the mid 7th to 9th century A.D. According to the results, five depositional phases can be recognized, and the related shoreline reconstruction shows a general trend of a flooded terrestrial landscape. This 'flooding' relates well to relative sea-level curves published in the region. Continued analysis of results from the research, and future research activities, may make it possible to recognize hurricane proxies in the sediment, locate underwater manmade seafaring artifacts and facilities, determine the range of economic opportunities for past inhabitants and quantify the availability of potable water sources.

  10. Influence of exposure regimen on nitrogen dioxide-induced morphological changes in the rat lung

    SciTech Connect

    Rombout, P.J.A.; Dormans, J.A.M.A.; Marra, M.; van Esch, G.J.

    1986-12-01

    Experiments were performed to study the influence of concentration, exposure pattern, and length of exposure on the degree and extent of morphological alterations in the NO/sub 2//sup -/ exposed rat lung. Four weeks of continuous exposure to 20 mg NO/sub 2//m/sup 3/ consecutively revealed damage and loss of cilia, replacement of desquamated type I pneumocytes by type II pneumocytes resulting in a cuboidal epithelial lining, an influx of alveolar macrophages, and hypertrophy and hyperplasia of the bronchiolar epithelium. The animals recovered almost completely from the induced lesions within 8 days. Continuous exposure to 1, 2.5, or 5 mg/m/sup 3/ displayed minimal alterations in the 5 mg/m/sup 3/ group. The effects increased with exposure time. Intermittent or continuous exposure to 20 mg NO/sub 2//m/sup 3/ resulted in minor differences after 4 weeks. The onset of the lesions was delayed and the massive influx of alveolar macrophages in the continuously exposed animals failed to appear in the intermittently exposed animals. This work demonstrates that in subacute experiments: (1) Concentration plays a more important role in inducing pulmonary lesions than exposure time when the product of concentration and time is kept constant. This effect is stronger during intermittent exposure than during continuous exposure. (2) Continuous exposure seems to be a more important factor with regard to a macrophage response than intermittent exposure. (3) The rat lung has a large capacity to repair almost completely from damage caused by short-term NO/sub 2/ exposure.

  11. MORPHOLOGIC ANALYSIS CORRELATES WITH GENE EXPRESSION CHANGES IN CULTURED F344 RAT MESOTHELIAL CELLS

    EPA Science Inventory

    The gene expression pattern of mesothelial cells in vitro was determined after 4 or 12 h exposure to the rat mesothelial, kidney and thyroid carcinogen, and oxidative stressor potassium bromate (KBr03). Gene expression changes observed using cDNA arrays indicated oxidative stres...

  12. MORPHOLOGICAL CHANGES IN POLYURETHANE COATINGS ON EXPOSURE TO WATER. (R828081E01)

    EPA Science Inventory

    When a polyurethane self-priming coating on a sol-gel treated aluminum panel was immersed in dilute Harrison's solution, subsequent change of the polyurethane coating surface was inspected with atomic force microscopy (AFM) and scanning electron microscopy (SEM). After immersi...

  13. USUING STREAM MORPHOLOGY CLASSIFICATION TO MANAGE ECOLOGICAL RISKS FROM LAND USE CHANGES IN THE LMR WATERSHED

    EPA Science Inventory

    Changes in the amount and types of land use in a watershed can destabilize stream channel structure, increase sediment loading and degrade in-stream habitat. Stream classification systems (e.g. Rosgen) may be useful for determining the susceptibility of stream channel segments t...

  14. USING STREAM MORPHOLOGY CLASSIFICATION TO MANAGE ECOLOGICAL RISKS FROM LAND USE CHANGES IN THE LMR WATERSHED

    EPA Science Inventory

    Changes in the amount and types of land use in a watershed can destabilize stream channel structure, increase sediment loading and degrade in-stream habitat. Stream classification systems (e.g. Rosgen) may be useful for determining the susceptibility of stream channel segments t...

  15. Are morphological changes necessary to mediate the therapeutic effects of electroconvulsive therapy?

    PubMed

    Nickl-Jockschat, Thomas; Palomero Gallagher, Nicola; Kumar, Vinod; Hoffstaedter, Felix; Brügmann, Elisabeth; Habel, Ute; Eickhoff, Simon B; Grözinger, Michael

    2016-04-01

    The neurotrophic hypothesis has become the favorite model to explain the antidepressant properties of electroconvulsive therapy (ECT). It is based on the assumption that a restoration of previously defective neural networks drives therapeutic effects. Recent data in rather young patients suggest that neurotrophic effects of ECT might be detectable by diffusion tensor imaging. We here aimed to investigate whether the therapeutic response to ECT necessarily goes along with mesoscopic effects in gray matter (GM) or white matter (WM) in our patients in advanced age. Patients (n = 21, 15 males and 7 females) suffering from major depressive disorder were treated with ECT. Before the start of treatment and after the completion of the index series, they underwent magnetic resonance imaging, including a diffusion-weighed sequence. We used voxel-based morphometry to assess GM changes and tract-based spatial statistics and an SPM-based whole-brain analysis to detect WM changes in the course of treatment. Patients significantly improved clinically during the course of ECT. This was, however, not accompanied by GM or WM changes. This result challenges the notion that mesoscopic brain structure changes are an obligatory prerequisite for the antidepressant effects of ECT. PMID:26260901

  16. Temporal dynamics of changes in reactive oxygen species (ROS) levels and cellular morphology are coordinated during complementary chromatic acclimation in Fremyella diplosiphon.

    PubMed

    Singh, Shailendra P; Miller, Haley L; Montgomery, Beronda L

    2013-10-14

    Fremyella diplosiphon alters the phycobiliprotein composition of its light-harvesting complexes, i.e., phycobilisomes, and its cellular morphology in response to changes in the prevalent wavelengths of light in the external environment in a phenomenon known as complementary chromatic acclimation (CCA). The organism primarily responds to red light (RL) and green light (GL) during CCA to maximize light absorption for supporting optimal photosynthetic efficiency. Recently, we found that RL-characteristic spherical cell morphology is associated with higher levels of reactive oxygen species (ROS) compared to growth under GL where lower ROS levels and rectangular cell shape are observed. The RL-dependent association of increased ROS levels with cellular morphology was demonstrated by treating cells with a ROS-scavenging antioxidant which resulted in the observation of GL-characteristic rectangular morphology under RL. To gain additional insights into the involvement of ROS in impacting cellular morphology changes during CCA, we conducted experiments to study the temporal dynamics of changes in ROS levels and cellular morphology during transition to growth under RL or GL. Alterations in ROS levels and cell morphology were found to be correlated with each other at early stages of acclimation of low white light-grown cells to growth under high RL or cells transitioned between growth in RL and GL. These results provide further general evidence that significant RL-dependent increases in ROS levels are temporally correlated with changes in morphology toward spherical. Future studies will explore the light-dependent mechanisms by which ROS levels may be regulated and the direct impacts of ROS on the observed morphology changes. PMID:24122367

  17. [Morphological changes in the liver of rats subjected to deficient diet and bromex administration].

    PubMed

    Krustev, L; Tasheva, M; Kaloianova-Simeonova, F

    1982-01-01

    An experiment was carried out with male albino rats, with a mean body weight 165 g, grouped into 4 groups: on protein deficiency diet (with 3.8% protein in food), 4-week treatment with 1/50 LD50 bromex and a control group (not treated). It was established that the separate bromex treatment of the animals or their putting on a 6-week deficiency diet led to moderate changes in hepatocyte organelles. The combined effect of both factors--bromex and deficiency diet--sums the effect leading to the reduction of chromatin inclusions of the nuclei, reduces the amount of GER, Ser and mitochondria, dystrophic changes in mitochondria, increase of secondary lysozyomes and build up of fatty acids in hepatocytes. PMID:7178068

  18. Characteristic morphological and frictional changes in sputtered MoS/sub 2 films

    NASA Technical Reports Server (NTRS)

    Spalvins, T.

    1984-01-01

    Three microstructural growth stages of sputtered MoS2 films were identified with respect to film thickness: (1) ridge formation during nucleation, (2) an equiaxed transition zone, and (3) a columnar-fiber-like structure. Each of these growth stages are characterized in terms of microcrystallite size, shape, and orientation. The effective lubricating film thickness is established in terms of the microstructural growth stages during sliding experiments. The film has a tendency to break up within the columnar zone. Actual lubrication is performed by the remaining film which is 0.18 to 0.22 microns thick. Also a visual screening is proposed to evaluate the integrity of the as-sputtered MoS2 film. The lubricating properties are identified with respect to optical changes before and after wiping. The orientation of the microcrystallites are responsible for the optical reflective changes observed.

  19. [Morphological changes in the respiratory organs in chronic obstructive pulmonary disease].

    PubMed

    Malykhin, F T; Kostornaya, I V

    2016-01-01

    The basis for airway remoldeling in patients with chronic obstructive pulmonary disease (COPD) is tissue changes contributing to thickening of the walls of the airway and its obstruction. As the disease becomes severer, there are increases in mucosal metaplasia, submucosal hypertrophy, peribronchial fibrosis, and airway smooth muscle mass. Drug therapy for COPD does not virtually lead to regression of airway obstruction, except when eosinophilia is present. PMID:27077144

  20. The response of tidal morphologies to changing physical and biological forcings

    NASA Astrophysics Data System (ADS)

    D'Alpaos, A.; da Lio, C.; Marani, M.

    2009-12-01

    In times of natural climate changes and human interferences, tidal ecosystems are most exposed to possibly irreversible transformations, with far-reaching ecological, economical and social implications worldwide. Relative sea-level fluctuations, changes in nutrient and sediment loading, and ecological characteristics expose tidal ecosystems to responses which may or may not be reversible. Improving our understanding of the chief landforming processes which drive their morphogenesis and long-term evolution, is deemed to be a subject of leading theoretical and practical importance. We have modelled the joint evolution of tidal landforms and biota including the dynamics of intertidal vegetation, benthic microbial assemblages, erosional and depositional processes, local and general hydrodynamics, and relative sea-level change. Alternative stable states and punctuated equilibrium dynamics emerge, characterized by possible sudden transitions of the system, governed by vegetation type, disturbances of the benthic biofilm, sediment availability, wind climate, local hydrodynamics, and the vagaries of relative sea level rise. The existence of feedbacks between physical and biological processes affect trajectories characterizing the evolution of these ecosystems and the reversibility of such trajectories. They highlight the importance of the coupling between biological and sediment transport processes in determining the evolution of a tidal system as a whole.

  1. Morphological and immunohistological changes in the skin in allogeneic bone marrow recipients.

    PubMed Central

    Sloane, J P; Thomas, J A; Imrie, S F; Easton, D F; Powles, R L

    1984-01-01

    Skin biopsies from leukaemic patients undergoing allogeneic bone marrow transplantations and treated prophylactically with cyclosporin A were analysed using histological, morphometric, and immunohistological techniques. Samples from donors were used to establish normal values. Biopsies taken from recipients two days before grafting were all histologically normal, but on immunohistological staining half of them showed a reduction in the number of epidermal Langerhans' cells and 29% a reduction in T inducer lymphocytes. Thirty two biopsies were taken from patients with rashes at various times after transplantation: 14 showed lichenoid changes consistent with graft versus host disease, three eczematous tissue reactions, two vesicular lesions, and 12 no histological abnormality. One sample showed changes intermediate between the lichenoid and eczematous forms. The numbers of epidermal Langerhans' cells were low during the first few weeks after transplantation and were normal or raised later regardless of histological appearances. Unlike epidermal Langerhans' cells, significant reductions in the numbers of lymphocytes were not seen. Lesions of all histological types contained mixtures of T inducer and T suppressor/cytotoxic cells, although the eczematous and vesicular lesions contained higher proportions of T inducer cells. Epidermal infiltrates invariably contained T suppressor/cytotoxic cells but infiltration of epidermis by T inducer cells occurred only in the presence of normal numbers of epidermal Langerhans' cells. Natural killer cells were not identified. The immunological appearances of the various histological subgroups thus change with time after transplantation. Images PMID:6381547

  2. Morphological Changes, Evidence for a Collimating Disk, and Extremely Young Jetlike Components in the Planetary Nebula IC 4997

    NASA Astrophysics Data System (ADS)

    Miranda, Luis F.; Torrelles, José M.

    1998-03-01

    We present VLA-A radio continuum observations at 3.6 cm and 2 cm of the extremely young, double-shell planetary nebula IC 4997. A comparison of the new 3.6 cm map with that obtained in 1995 July shows that morphological changes have occurred in the nebula in ~=1.3 yr. These changes reveal themselves by the presence in the outer shell of several new bright compact regions, most of which are located along the major nebular axis. The observed changes suggest that a variable highly collimated stellar wind impinges on the outer shell and causes variation of the physical conditions in compact nebular regions. This mechanism is probably related to the origin of the microstructure in IC 4997. The inner shell has been resolved at 2 cm and shows an elliptical morphology with a deconvolved size of ~=0.12" × 0.09" (P.A. ~= 56°). Evidence for an extended, flat equatorial disk (size ~=1.4" × 0.22", P.A. ~= 125°) is found at 2 cm. The derived spectral index α(3.6-2 cm) map of the nebula reveals a compact (size ~= 0.5" × 0.2", P.A. ~= 125°), dense [Ne ~= (2-6) × 105 cm-3], optically thick (τ3.6 cm ~= 1-8) band that probably represents the innermost, densest regions of the extended disk. This disk can be identified as the collimating agent of both the inner and outer shells. In addition, extremely young bipolar jetlike features are observed along the major axis of the inner shell, exhibiting the typical properties of jetlike outflows in planetary nebulae.

  3. Functional and Morphological Changes in Endocrine Pancreas following Cola Drink Consumption in Rats

    PubMed Central

    2015-01-01

    Aim We report the effects of long-term cola beverage drinking on glucose homeostasis, endocrine pancreas function and morphology in rats. Methods Wistar rats drank: water (group W), regular cola beverage (group C, sucrose sweetened) or “light” cola beverage (group L, artificially sweetened). After 6 months, 50% of the animals in each group were euthanized and the remaining animals consumed water for the next 6 months when euthanasia was performed. Biochemical assays, insulinemia determination, estimation of insulin resistance (HOMA-IR), morphometry and immunohistochemistry evaluations were performed in pancreas. Results Hyperglycemia (16%, p<0.05), CoQ10 (coenzyme-Q10) decrease (−52%,p<0.01), strong hypertriglyceridemia (2.8-fold, p<0.01), hyperinsulinemia (2.4 fold, p<0.005) and HOMA-IR increase (2.7 fold, p<0.01) were observed in C. Group C showed a decrease in number of α cells (−42%, p<0.01) and β cells (−58%, p<0.001) and a moderate increase in α cells’ size after wash-out (+14%, p<0.001). Group L showed reduction in β cells’ size (−9%, p<0.001) and only after wash-out (L12) a 19% increase in size (p<0.0001) with 35% decrease in number of α cells (p<0.01). Groups C and L showed increase in α/β-cell ratio which was irreversible only in C (α/β = +38% in C6,+30% in C12, p<0.001vs.W6). Regular cola induced a striking increase in the cytoplasmic expression of Trx1 (Thioredoxin-1) (2.25-fold in C6 vs. W6; 2.7-fold in C12 vs. W12, p<0.0001) and Prx2 (Peroxiredoxin-2) (3-fold in C6 vs. W6; 2-fold in C12 vs. W12, p<0.0001). Light cola induced increase in Trx1 (3-fold) and Prx2 (2-fold) after wash-out (p<0.0001, L12 vs. W12). Conclusion Glucotoxicity may contribute to the loss of β cell function with depletion of insulin content. Oxidative stress, suggested by increased expression of thioredoxins and low circulating levels of CoQ10, may follow sustained hyperglycemia. A likely similar panorama may result from the effects of artificially

  4. Monitoring Changes in Channel Morphology in Las Vegas Wash with Global Fiducials Program Imagery

    NASA Astrophysics Data System (ADS)

    Wheeler, D. J.

    2012-12-01

    obstructions in the channel. The replanting of native vegetation on storm debris flats is stabilizing some of the soil in the wash and also rejuvenating much of the wetland habitat. Las Vegas Wash is a test bed for the design and implementation of innovative methods for modifying stream morphology to achieve desirable results, as some of these methods are deemed successful and some are not as effective. The lessons learned about curbing erosion and sediment transport within Las Vegas Wash may be applied to other urban streams in arid environments.

  5. Beach morphology and change along the mixed grain-size delta of the dammed Elwha River, Washington

    USGS Publications Warehouse

    Warrick, J.A.; George, D.A.; Gelfenbaum, G.; Ruggiero, P.; Kaminsky, G.M.; Beirne, M.

    2009-01-01

    Sediment supply provides a fundamental control on the morphology of river deltas, and humans have significantly modified these supplies for centuries. Here we examine the effects of almost a century of sediment supply reduction from the damming of the Elwha River in Washington on shoreline position and beach morphology of its wave-dominated delta. The mean rate of shoreline erosion during 1939-2006 is ~ 0.6??m/yr, which is equivalent to ~ 24,000??m3/yr of sediment divergence in the littoral cell, a rate approximately equal to 25-50% of the littoral-grade sediment trapped by the dams. Semi-annual surveys between 2004 and 2007 show that most erosion occurs during the winter with lower rates of change in the summer. Shoreline change and morphology also differ spatially. Negligible shoreline change has occurred updrift (west) of the river mouth, where the beach is mixed sand to cobble, cuspate, and reflective. The beach downdrift (east) of the river mouth has had significant and persistent erosion, but this beach differs in that it has a reflective foreshore with a dissipative low-tide terrace. Downdrift beach erosion results from foreshore retreat, which broadens the low-tide terrace with time, and the rate of this kind of erosion has increased significantly from ~ 0.8??m/yr during 1939-1990 to ~ 1.4??m/yr during 1990-2006. Erosion rates for the downdrift beach derived from the 2004-2007 topographic surveys vary between 0 and 13??m/yr, with an average of 3.8??m/yr. We note that the low-tide terrace is significantly coarser (mean grain size ~ 100??mm) than the foreshore (mean grain size ~ 30??mm), a pattern contrary to the typical observation of fining low-tide terraces in the region and worldwide. Because this cobble low-tide terrace is created by foreshore erosion, has been steady over intervals of at least years, is predicted to have negligible longshore transport compared to the foreshore portion of the beach, and is inconsistent with oral history of abundant

  6. Catecholamines of the adrenal medula and their morphological changes during adaptation to repeated immobilization stress

    NASA Technical Reports Server (NTRS)

    Kvetnansky, R.; Mitro, A.; Mikulaj, L.; Hocman, G.

    1980-01-01

    Changes of the adrenal medulla of rats were studied in the course of adaptation to repeated immobilization stress. An increase in the number of cells in the adrenal medulla was found in the adapted animals; this increase was confirmed by weight indices of the medulla and by cell counts per surface unit. Simultaneous karyometric measurements of the nuclei of adrenal medulla cells and an analysis of the catecholamine contents in the adrenals explain the increased activity of the adrenal medulla in the course of adaptation.

  7. He-Ion and Self-Atom Induced Damage and Surface-Morphology Changes of a Hot W Target

    SciTech Connect

    Meyer, Fred W; Hijazi, Hussein Dib; Krstic, Predrag S; Dadras, Mostafa Jonny; Meyer III, Harry M; Parish, Chad M; Bannister, Mark E

    2014-01-01

    We report results of measurements on the evolution of the surface morphology of a hot tungsten surface due to impacting low-energy (80 12,000 eV) He ions and of simulations of damage caused by cumulative bombardment of 1 and 10 keV W self-atoms. The measurements were performed at the ORNL Multicharged Ion Research Facility (MIRF), while the simulations were done at the Kraken supercomputing facility of the University of Tennessee. At 1 keV, the simulations show strong defect-recombination effects that lead to a saturation of the total defect number after a few hundreds impacts, while sputtering leads to an imbalance of the vacancy and interstitial number. On the experimental side, surface morphology changes were investigated over a broad range of fluences for both virgin and pre-damaged W-targets. At the lowest accumulated fluences, small surface-grain features and near-surface He bubbles are observed. At the largest fluences, individual grain characteristics disappear in FIB/SEM scans, and the entire surface is covered by a multitude of near-surface bubbles with a broad range of sizes, and disordered whisker growth, while in top-down SEM imaging the surface is virtually indistinguishable from the nano-fuzz produced on linear plasma devices. These features are evident at progressively lower fluences as the He-ion energy is increased.

  8. Morphological study of the human hyoid bone with three-dimensional CT images -Gender difference and age-related changes.

    PubMed

    Ito, Kyoichi; Ando, Satoshi; Akiba, Norihiko; Watanabe, Yuichi; Okuyama, Yasuo; Moriguchi, Hisamoto; Yoshikawa, Kohki; Takahashi, Tsuneo; Shimada, Morio

    2012-01-01

    The human hyoid bone supports the base of the tongue and is involved in breathing, chewing, and swallowing as well as in the muscle movements associated with articulation. Accordingly it plays an important bone for a human to live. It is a very interesting organ also in multiple special area, including anatomy, mastication, swallowing, articulation, and also forensic medicine. In the morphological study of the human hyoid bone, there is a comparative anthropological research early in 1900, whereas the metrological research has been little reported later. We first used MDCT, and recorded each organic hyoid locus with a three-dimensional image for three-dimensional morphometry of gender differences, age-related changes, and the morphologic characters of the hyoid bone, and compared them with the results of our predecessors. By measuring the volume of the human hyoid bone, we identified gender difference at high rates, and estimated a certain level of ages based on the ossification at the junction area of the hyoid body and greater horns observed. Our results can be applied in the forensic medicine. By examining 600 cases, atypical horseshoes-shapes were found and the existence of the hyoid bone protrusion was demonstrated at high rates. PMID:23429053

  9. Phorbol 12-myristate 13-acetate prevents isoproterenol-induced morphological change in cultured vascular smooth muscle cells

    SciTech Connect

    Nabika, Toru; Chaldakov, G.N.; Nara, Yasuo; Endo, Jiro; Yamori, Yukio )

    1988-10-01

    The effect of phorbol 12-myristate 13-acetate (PMA) on isoproterenol (ISO)- and dibutyryl cAMP (dBcAMP)-induced morphological change and cytoskeletal reorganization was studied in cultured vascular smooth muscle cells (VSMC) using the fluorescence staining of actin and microtubules. The treatment of VSMC with 1.0 {mu}M of ISO or with 1.0 mM of dBcAMP for 90 min induced the disruption of actin-containing stress fibers followed by cytoplasmic arborization. The addition of 100 nM of PMA prevented both the destruction of actin fibers and cell arborization induced either by ISO or by dBcAMP. These results indicated that the inhibition of arborization by PMA was mediated through the activation of protein kinase C. Colchicine at 5.0 {mu}M also had an inhibitory effect on ISO- and dBcAMP-induced cell arborization. However, immunofluorescence studies revealed that colchicine but not PMA elicited the reorganization of microtubules, suggesting that the effect of PMA was mediated through a mechanism different from that of colchicine. The observations indicated that the morphology of VSMC was regulated through the alteration of cytoskeletal organization induced by cAMP-mediated and by protein kinase C-dependent systems.

  10. Oenothein B inhibits the expression of PbFKS1 transcript and induces morphological changes in Paracoccidioides brasiliensis.

    PubMed

    Santos, Glaciane D; Ferri, Pedro H; Santos, Suzana C; Bao, Sônia N; Soares, Célia M A; Pereira, Maristela

    2007-11-01

    The fungus Paracoccidioides brasiliensis is the causative agent of paracoccidioidomycosis (PCM), the most prevalent human systemic mycosis in Latin America. Drug toxicity and the appearance of resistant strains have created the need to search for new therapeutic approaches. Plants with reputed antimicrobial properties represent a rich screening source of potential antifungal compounds. In this work, the growth of P. brasiliensis yeast cells was evaluated in the presence of oenothein B extracted from Eugenia uniflora. The oenothein B dosage that most effectively inhibited the development (74%) of P. brasiliensis yeast cells in vitro was 500 microg/ml. To verify if oenothein B interferes with cell morphology, we observed oenothein B-treated yeast cells by electron microscopy. The micrographs showed characteristic cell changes noted with glucan synthesis inhibition, including squashing, rough surface, cell wall rupture and cell membrane recess. The expression of P. brasiliensis genes was evaluated in order to investigate the action of oenothein B. Here we report that oenothein B inhibits 1,3-beta-glucan synthase (PbFKS1) transcript accumulation. The results indicate that oenothein B interferes with the cell morphology of P. brasiliensis, probably by inhibiting the transcription of 1,3-beta-glucan synthase gene, which is involved in the cell wall synthesis. PMID:18033615

  11. He-ion and self-atom induced damage and surface-morphology changes of a hot W target

    NASA Astrophysics Data System (ADS)

    Meyer, F. W.; Hijazi, H.; Bannister, M. E.; Krstic, P. S.; Dadras, J.; Meyer, H. M., III; Parish, C. M.

    2014-04-01

    We report results of measurements on the evolution of the surface morphology of a hot tungsten surface due to impacting low-energy (80-12 000 eV) He ions and of simulations of damage caused by cumulative bombardment of 1 and 10 keV W self-atoms. The measurements were performed at the ORNL Multicharged Ion Research Facility, while the simulations were done at the Kraken supercomputing facility of the University of Tennessee. At 1 keV, the simulations show strong defect-recombination effects that lead to a saturation of the total defect number after a few hundred impacts, while sputtering leads to an imbalance of the vacancy and interstitial number. On the experimental side, surface morphology changes were investigated over a broad range of fluences, energies and temperatures for both virgin and pre-damaged W-targets. At the lowest accumulated fluences, small surface-grain features and near-surface He bubbles are observed. At the largest fluences, individual grain characteristics disappear in focused ion beam/scanning electron microscopy (FIB/SEM) scans, and the entire surface is covered by a multitude of near-surface bubbles with a broad range of sizes, and disordered whisker growth, while in top-down SEM imaging the surface is virtually indistinguishable from the nano-fuzz produced on linear plasma devices. These features are evident at progressively lower fluences as the He-ion energy is increased.

  12. Rates of change and Sensitivity to Change in Cartilage Morphology in Healthy Knees and in Knees with Mild, Moderate, and End Stage Radiographic Osteoarthritis

    PubMed Central

    Eckstein, Felix; Nevitt, Michael; Gimona, Alberto; Picha, Kristen; Lee, Jennifer H; Davies, Richard Y; Dreher, Donatus; Benichou, Olivier; Le Graverand, Marie-Pierre Hellio; Hudelmaier, Martin; Maschek, Susanne; Wirth, Wolfgang

    2011-01-01

    Objective To study the longitudinal rate of (and sensitivity to) change of knee cartilage thickness across defined stages of radiographic osteoarthritis (ROA), specifically healthy knees and knees with end-stage ROA. Methods One knee of 831 Osteoarthritis Initiative (OAI) participants was examined: 112 healthy, without ROA or risk factors for knee OA, and 719 ROA knees: 310 calculated Kellgren Lawrence [cKLG] grade 2, 300 cKLG3, and 109 cKLG4. Subregional change in thickness was assessed after segmentation of weight-bearing femorotibial cartilage at baseline and at one year from coronal MRI. Regional and ordered values (OV) of change were compared by baseline ROA status. Results Healthy knees displayed small changes in plates and subregions (±0.7%; standardized response mean [SRM] ±0.15), with OVs being symmetrically distributed around zero. In cKLG2 knees, changes in cartilage thickness were small (≤1%; minimal SRM -0.22) and not significantly different from healthy knees. Knees with cKLG3 showed substantial loss of cartilage thickness (up to -2.5%; minimal SRM -0.35), with OV changes being significantly (p<0.05) greater than those in healthy knees. cKLG4 knees displayed the largest rate of loss across ROA grades (up to -3.9%; minimal SRM -0.51), with OV changes also significantly (p<0.05) greater than in healthy knees. Conclusion MRI-based cartilage thickness showed high rates of loss in knees with moderate and end-stage ROA, and small rates (indistinguishable from healthy knees) in mild ROA. From the perspective of sensitivity to change, end-stage ROA knees need not be excluded from longitudinal studies using MRI cartilage morphology as an endpoint. PMID:20957657

  13. Growth Mechanism of Strain-Dependent Morphological Change in PEDOT:PSS Films

    PubMed Central

    Lee, Yoo-Yong; Choi, Gwang Mook; Lim, Seung-Min; Cho, Ju-Young; Choi, In-Suk; Nam, Ki Tae; Joo, Young-Chang

    2016-01-01

    Understanding the mechanism of the strain-dependent conductivity change in polymers in stretched conditions is important. We observed a strain-induced growth of the conductive regions of PEDOT:PSS films, induced by a coalescence of conductive PEDOT-rich cores. This growth due to coalescence leads to a gradual decrease in the electrical resistivity up to 95%, independent of the thickness of the PEDOT:PSS films. The primary mechanism for the evolution of the PEDOT-rich cores proceeds by the cores growing larger as they consuming relatively smaller cores. This process is caused by a strain-induced local rearrangement of PEDOT segments in the vicinity of PSS shells around the cores and also changes the chemical environment in PEDOT, induced by the electron-withdrawing effects around the PEDOT chains. The strain-induced growth mechanism is beneficial to understanding the phenomenon of polymeric chain rearrangement in mechanical deformation and to modulating the electrical conductivity for practical applications. PMID:27125340

  14. Temporary morphological changes in plus disease induced during contact digital imaging

    PubMed Central

    Zepeda-Romero, L C; Martinez-Perez, M E; Ruiz-Velasco, S; Ramirez-Ortiz, M A; Gutierrez-Padilla, J A

    2011-01-01

    Objective To compare and quantify the retinal vascular changes induced by non-intentional pressure contact by digital handheld camera during retinopathy of prematurity (ROP) imaging by means of a computer-based image analysis system, Retinal Image multiScale Analysis. Methods A set of 10 wide-angle retinal pairs of photographs per patient, who underwent routine ROP examinations, was measured. Vascular trees were matched between ‘compression artifact' (absence of the vascular column at the optic nerve) and ‘not compression artifact' conditions. Parameters were analyzed using a two-level linear model for each individual parameter for arterioles and venules separately: integrated curvature (IC), diameter (d), and tortuosity index (TI). Results Images affected with compression artifact showed significant vascular d (P<0.01) changes in both arteries and veins, as well as in artery IC (P<0.05). Vascular TI remained unchanged in both groups. Conclusions Non-adverted corneal pressure with the RetCam lens could compress and decrease intra-arterial diameter or even collapse retinal vessels. Careful attention to technique is essential to avoid absence of the arterial blood column at the optic nerve head that is indicative of increased pressure during imaging. PMID:21760627

  15. Cucumarioside A2-2 causes changes in the morphology and proliferative activity in mouse spleen.

    PubMed

    Pislyagin, E A; Manzhulo, I V; Dmitrenok, P S; Aminin, D L

    2016-05-01

    The immunomodulatory effect of triterpene glycoside cucumarioside A2-2 (CA2-2), isolated from the Far Eastern sea cucumber Cucumaria japonica, on the mouse spleen was investigated in comparison with lipopolysaccharide (LPS). It has been shown that the intraperitoneal (i.p.) glycoside administration did not influence on splenic weights, while the statistically significant increase in splenic weight was observed after LPS administration. Changes in the ratio of red to white pulp after CA2-2 or LPS administration were observed. The proportion of splenic white pulp after glycoside or LPS administration increased by up to 34% and 36%, respectively. A detailed study of the distribution of the РСNA (Proliferating Cell Nuclear Antigen) marker showed that the proliferative activity in the white pulp under CA2-2 and LPS influence increased 2.07 and 2.24 times, respectively. The localization of PCNA-positive nuclei in the white pulp region, as well as their dimensional characteristics, suggests that a large proportion of the proliferating cell population consisted of B cells. The mass spectrometry profiles of spleen peptide/protein homogenate were obtained using the MALDI-TOF-MS (Matrix -Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry) approach. It was found that i.p. stimulation of animals with CA2-2 or LPS leads to marked changes in the intensity of revealed characteristic peaks of peptides/proteins after exposure to immunostimulants. PMID:27079859

  16. Morphological changes of glutamatergic synapses in animal models of Parkinson’s disease

    PubMed Central

    Villalba, Rosa M.; Mathai, Abraham; Smith, Yoland

    2015-01-01

    The striatum and the subthalamic nucleus (STN) are the main entry doors for extrinsic inputs to reach the basal ganglia (BG) circuitry. The cerebral cortex, thalamus and brainstem are the key sources of glutamatergic inputs to these nuclei. There is anatomical, functional and neurochemical evidence that glutamatergic neurotransmission is altered in the striatum and STN of animal models of Parkinson’s disease (PD) and that these changes may contribute to aberrant network neuronal activity in the BG-thalamocortical circuitry. Postmortem studies of animal models and PD patients have revealed significant pathology of glutamatergic synapses, dendritic spines and microcircuits in the striatum of parkinsonians. More recent findings have also demonstrated a significant breakdown of the glutamatergic corticosubthalamic system in parkinsonian monkeys. In this review, we will discuss evidence for synaptic glutamatergic dysfunction and pathology of cortical and thalamic inputs to the striatum and STN in models of PD. The potential functional implication of these alterations on synaptic integration, processing and transmission of extrinsic information through the BG circuits will be considered. Finally, the significance of these pathological changes in the pathophysiology of motor and non-motor symptoms in PD will be examined. PMID:26441550

  17. Transformation of Face Transplants: Volumetric and Morphologic Graft Changes Resemble Aging After Facial Allotransplantation.

    PubMed

    Kueckelhaus, M; Turk, M; Kumamaru, K K; Wo, L; Bueno, E M; Lian, C G; Alhefzi, M; Aycart, M A; Fischer, S; De Girolami, U; Murphy, G F; Rybicki, F J; Pomahac, B

    2016-03-01

    Facial allotransplantation restores normal anatomy to severely disfigured faces. Although >30 such operations performed worldwide have yielded promising short-term results, data on long-term outcomes remain scarce. Three full-face transplant recipients were followed for 40 months. Severe changes in volume and composition of the facial allografts were noted. Data from computed tomography performed 6, 18 and 36 months after transplantation were processed to separate allograft from recipient tissues and further into bone, fat and nonfat soft tissues. Skin and muscle biopsies underwent diagnostic evaluation. All three facial allografts sustained significant volume loss (mean 19.55%) between 6 and 36 months after transplant. Bone and nonfat soft tissue volumes decreased significantly over time (17.22% between months 6 and 18 and 25.56% between months 6 and 36, respectively), whereas fat did not. Histological evaluations showed atrophy of muscle fibers. Volumetric and morphometric changes in facial allografts have not been reported previously. The transformation of facial allografts in this study resembled aging through volume loss but differed substantially from regular aging. These findings have implications for risk-benefit assessment, donor selection and measures counteracting muscle and bone atrophy. Superior long-term outcomes of facial allotransplantation will be crucial to advance toward future clinical routine. PMID:26639618

  18. Changes in Morphology, Gene Expression and Protein Content in Chondrocytes Cultured on a Random Positioning Machine

    PubMed Central

    Aleshcheva, Ganna; Sahana, Jayashree; Ma, Xiao; Hauslage, Jens; Hemmersbach, Ruth; Egli, Marcel; Infanger, Manfred; Bauer, Johann; Grimm, Daniela

    2013-01-01

    Tissue engineering of chondrocytes on a Random Positioning Machine (RPM) is a new strategy for cartilage regeneration. Using a three-dimensional RPM, a device designed to simulate microgravity on Earth, we investigated the early effects of RPM exposure on human chondrocytes of six different donors after 30 min, 2 h, 4 h, 16 h, and 24 h and compared the results with the corresponding static controls cultured under normal gravity conditions. As little as 30 min of RPM exposure resulted in increased expression of several genes responsible for cell motility, structure and integrity (beta-actin); control of cell growth, cell proliferation, cell differentiation and apoptosis (TGF-β1, osteopontin); and cytoskeletal components such as microtubules (beta-tubulin) and intermediate filaments (vimentin). After 4 hours of RPM exposure disruptions in the vimentin network were detected. These changes were less dramatic after 16 hours on the RPM, when human chondrocytes appeared to reorganize their cytoskeleton. However, the gene expression and protein content of TGF-β1 was enhanced during RPM culture for 24 h. Taking these results together, we suggest that chondrocytes exposed to the RPM seem to change their extracellular matrix production behaviour while they rearrange their cytoskeletal proteins prior to forming three-dimensional aggregates. PMID:24244418

  19. Plant–pathogen interactions and elevated CO2: morphological changes in favour of pathogens

    PubMed Central

    Lake, Janice Ann; Wade, Ruth Nicola

    2009-01-01

    Crop losses caused by pests and weeds have been estimated at 42% worldwide, with plant pathogens responsible for almost $10 billion worth of damage in the USA in 1994 alone. Elevated carbon dioxide [ECO2] and associated climate change have the potential to accelerate plant pathogen evolution, which may, in turn, affect virulence. Plant–pathogen interactions under increasing CO2 concentrations have the potential to disrupt both agricultural and natural systems severely, yet the lack of experimental data and the subsequent ability to predict future outcomes constitutes a fundamental knowledge gap. Furthermore, nothing is known about the mechanistic bases of increasing pathogen agressiveness. In the absence of information on crop species, it is shown here that plant pathogen (Erysiphe cichoracearum) aggressiveness is increased under ECO2, together with changes in the leaf epidermal characteristics of the model plant Arabidopsis thaliana L. Stomatal density, guard cell length, and trichome numbers on leaves developing post-infection are increased under ECO2 in direct contrast to non-infected responses. As many plant pathogens utilize epidermal features for successful infection, these responses provide a positive feedback mechanism facilitating an enhanced susceptibility of newly developed leaves to further pathogen attack. Furthermore, a screen of resistant and susceptible ecotypes suggest inherent differences in epidermal responses to ECO2. PMID:19470658

  20. Interaction between Cities and Climate Change: Modelling Urban Morphology and Local Urban Planning Scenarios from Open Datasets across European Cities

    NASA Astrophysics Data System (ADS)

    Thomas, Bart; Stevens, Catherine; Grommen, Mart

    2015-04-01

    Cities are characterised by a large spatiotemporal diversity of local climates induced by a superposition of various factors and processes interacting at global and regional scales but also at the micro level such as the urban heat island effect. As urban areas are known as 'hot spots' prone to climate and its variability over time leading to changes in the severity and occurrence of extreme events such as heat waves, it is of crucial importance to capture the spatial heterogeneity resulting from variations in land use land cover (LULC) and urban morphology in an effective way to drive local urban climate simulations. The first part of the study conducted in the framework of the NACLIM FP7 project funded by the European Commission focusses on the extraction of land surface parameters linked to urban morphology characteristics from detailed 3D city models and their relationship with openly accessible European datasets such as the degree of soil sealing and disaggregated population densities from the European Environment Agency (EEA) and the Joint Research Centre (JRC). While it has been demonstrated that good correlations can be found between those datasets and the planar and frontal area indices, the present work has expanded the research to other urban morphology parameters including the average and variation of the building height and the sky view factor. Correlations up to 80% have been achieved depending on the considered parameter and the specific urban area including the cities of Antwerp (Belgium), Berlin (Germany) and Almada (Portugal) represented by different climate and urban characteristics. Moreover, the transferability of the established relations has been investigated across the various cities. Secondly, a flexible and scalable approach as a function of the required the level of detail has been elaborated to update the various morphology parameters in case of integration with urban planning data to analyse the local impact of future land use scenarios

  1. Morphologic changes in the thyroid after irradiation for Hodgkin's and non-Hodgkin's lymphoma

    SciTech Connect

    Carr, R.F.; LiVolsi, V.A.

    1989-08-15

    Four cases of thyroidectomy for suspected thyroid carcinoma after previous irradiation for Hodgkin's or non-Hodgkin's lymphoma are reviewed. The patients ranged in age from 18 to 33 years at the time of thyroid surgery with an average latency period of 12 years (range, 8-20 years) from radiation therapy to thyroidectomy. All patients had a clinically palpable thyroid nodule, and pathologically showed a pattern of multiple adenomatous nodules with cytologic atypia. The microscopic changes were sufficiently striking to cause the primary pathologist to request consultation to rule out thyroid carcinoma in each case. Fine-needle aspiration was performed in one case and suggested a thyroid neoplasm. The pathologic findings are reviewed and distinction of this lesion from thyroid carcinoma is discussed.

  2. [Morphological changes in the adenohypophysis during the recovery period after single individually graded physical exercise].

    PubMed

    Samarin, M Iu

    1983-02-01

    Morpho-functional changes occurring in the anterior principle part of the adenohypophysis have been studied light optically in dogs during the restorative period 1 day after the effect of single individually-dosed loadings of a moderate and great intensity. During one day the restoration of the gland is not completed. Certain structural signs that characterize the main regularities in the course of the restorative process have been revealed. Thus, an additional activation of the adenohypophysis during the restorative period makes it possible to suppose an oscillatory character of the restorative process, in particular--the supercompensation phase. Heterochronicity in restoration of some morpho-functional parameters of the gland has been also determined. It has been stated that manifestation of restoration in the anterior principle part of the adenohypophysis depends on the dose of the physical loading: the greater the loading, the more active, economic and effective is the restoration. PMID:6687799

  3. The changing morphology and increasing deceleration of supernova 1993J in M81

    PubMed

    Bartel; Bietenholz; Rupen; Beasley; Graham; Altunin; Venturi; Umana; Cannon; Conway

    2000-01-01

    Twenty consecutive Very Long Baseline Interferometry images of supernova 1993J from the time of explosion to the present show the dynamic evolution of the expanding radio shell of an exploded star. High-precision astrometry reveals that the supernova expands isotropically from its explosion center. Systematic changes in the images may reflect a pattern of anisotropies and inhomogeneities in the material left over from the progenitor star. As the shock front sweeps up the material in the surrounding medium, it is increasingly decelerated and influenced by the material. After 5 years, the supernova has slowed to half of its original expansion velocity and may have entered the early stages of the adiabatic phase common in much older supernova remnants in the Milky Way Galaxy. PMID:10615042

  4. Effects of UV-A Radiation on Desmodesmus armatus: Changes in Growth Rate, Pigment Content and Morphological Appearance

    NASA Astrophysics Data System (ADS)

    Pálffy, Károly; Vörös, Lajos

    2006-10-01

    Laboratory cultures of Desmodesmus armatus (R. Chod.) Hegew. were grown under different levels of photosynthetically active radiation (PAR) supplemented with 3.75 mW . cm-2 UV-A radiation. Growth rate was monitored daily, chlorophyl-a concentration, total carotenoid content, cell number and the relative abundance of different coenobial forms was determined at the end of each experiment. Exposure to UV-A radiation resulted in an increasing inhibition of growth towards higher PAR levels, reaching 100% at 400 μmol . m-2 . s-1. Cellular carotenoid content was higher in the presence of UV-A radiation, on the other hand no differences were observed in cellular chlorophyll-a concentration. UV-A radiation also induced changes in coenobium formation with a decreasing proportion of 4-celled coenobia and an increase in the abundance of 2-celled and teratologic coenobia, suggesting that high intensity UV-A radiation may influence cell cycle events or morphology development.

  5. Laser-writing inside uniaxially birefringent crystals: fine morphology of ultrashort pulse-induced changes in lithium niobate.

    PubMed

    Karpinski, P; Shvedov, V; Krolikowski, W; Hnatovsky, C

    2016-04-01

    This work presents a detailed analysis of the morphology of femtosecond laser-induced changes in bulk lithium niobate (LiNbO3) - one of the most common host materials in photonics - using second-harmonic generation microscopy and scanning electron microscopy. It is shown that focused linearly polarized near-infrared pulses can produce two or three distinct axially separated regions of modified material, depending on whether the pulse propagation is along or perpendicular to the optical axis. When laser writing in LiNbO3 is conducted in multi-shot irradiation mode and the focused light intensity is kept near the bulk damage threshold, periodic planar nanostructures aligned perpendicular to the laser polarization are produced inside the focal volume. These results provide a new perspective to laser writing in crystalline materials, including the fabrication of passive and active waveguides, photonic crystals, and optical data storage devices. PMID:27137036

  6. [Dose dependence of the frequency of morphological changes in Scots pine (Pinus sylvestris L.) in Chernobyl exclusion zone].

    PubMed

    Ioshchenko, V I; Bondar', Iu O

    2009-01-01

    Patterns and main parameters of the dynamics of radioactive contamination of organs of Scots pine in the plantations of Chernobyl zone are presented. On the basis of this data and within the frameworks of the microdosimetric approach, the dosimetric model for the apical meristem of the pine trees was created. The dose rates were calculated for the trees of the experimental array growing at three sites in the exclusion zone and one outside, which differed by three orders of magnitude of the trees' radioactive contamination levels. Comparable high, up to several Gy/y, levels of the dose rate of chronic irradiation were shown for the plantation at the Red Forest site. Such an expressed radiation factor results in a high frequency of the morphological changes at this site. The dose rate-effect dependence was formulated for this type of the radiobiological effects. PMID:19368333

  7. Irreversible morphological changes of a graphite negative-electrode at high potentials in LiPF6-based electrolyte solution.

    PubMed

    Domi, Yasuhiro; Doi, Takayuki; Tsubouchi, Shigetaka; Yamanaka, Toshiro; Abe, Takeshi; Ogumi, Zempachi

    2016-08-10

    The degradation mechanism of a graphite negative-electrode in LiPF6-based electrolyte solution was investigated using the basal plane of highly oriented pyrolytic graphite (HOPG) as a model electrode. Changes in the surface morphology were observed by in situ atomic force microscopy. In the initial cathodic scan, a number of pits appeared at around 1.75 V vs. Li(+)/Li, and fine particles formed on the terrace of the HOPG basal plane at about 1.5 V vs. Li(+)/Li. The fine particles were characterized by spectroscopic analysis, such as X-ray photoelectron spectroscopy and attenuated total reflection Fourier transform infrared spectroscopy. We added one of the components to LiClO4-based electrolyte solution, and successfully reproduced the formation of pits and fine particles on the basal plane of HOPG. Based on these results, the formation mechanisms of pits and fine particle layers were proposed. PMID:27465798

  8. Pickling of laser-cut NiTi slotted tube stents: Effect on surface morphology, dimension changes and mechanical behaviour

    NASA Astrophysics Data System (ADS)

    Zhao, H.; Stalmans, R.; van Humbeeck, J.; de Scheerder, I.

    2003-10-01

    Production of the NiTi slotted tube stents by laser cutting leads to strong burr formation and depositions on the material surface. Acid pickling is one of the major methods to remove the burr and the depositions. In this study, as a pre-treatment of polishing the NiTi stents, pickling was tested for various times in an acid solution at room temperature. Its effect on the surface morphology, dimension changes, and mechanical behaviour of the NiTi stents was evaluated. The burr and depositions could be removed practically. The removal (weight loss) of the material increases linearly with the pickling time. The burr and depositions were removed totally from the cutting zone when pickling time reached a specific value. Experimental relations among weight loss, dimensions, mechanical properties and pickling time of the NiTi stents were established.

  9. Pineal gland as an endocrine gravitational lunasensor: manifestation of moon-phase dependent morphological changes in mice.

    PubMed

    Gerasimov, A V; Kostyuchenko, V P; Solovieva, A S; Olovnikov, A M

    2014-10-01

    We found that some morphological properties of the pineal gland and submandibular salivary gland of mice are significantly distinct at the new and full moon. We suppose that the differences are initiated by the displacements of the electron-dense concretions in the secretory vesicles of pinealocytes. This presumably occurs under the influence of the gravitational field, which periodically changes during different phases of the moon. It seems that the pinealocyte is both an endocrine and gravisensory cell. A periodic secretion of the pineal gland probably stimulates, in a lunaphasic mode, the neuroendocrine system that, in turn, periodically exerts influence on different organs of the body. The observed effect probably serves, within the lifelong clock of a brain, to control development and aging in time. PMID:25519065

  10. A Morphological Study of Retinal Changes in Unilateral Amblyopia Using Optical Coherence Tomography Image Segmentation

    PubMed Central

    Szigeti, Andrea; Tátrai, Erika; Szamosi, Anna; Vargha, Péter; Nagy, Zoltán Zsolt; Németh, János; DeBuc, Delia Cabrera; Somfai, Gábor Márk

    2014-01-01

    Objective The purpose of this study was to evaluate the possible structural changes of the macula in patients with unilateral amblyopia using optical coherence tomography (OCT) image segmentation. Patients and Methods 38 consecutive patients (16 male; mean age 32.4±17.6 years; range 6–67 years) with unilateral amblyopia were involved in this study. OCT examinations were performed with a time-domain OCT device, and a custom-built OCT image analysis software (OCTRIMA) was used for OCT image segmentation. The axial length (AL) was measured by a LenStar LS 900 device. Macular layer thickness, AL and manifest spherical equivalent refraction (MRSE) of the amblyopic eye were compared to that of the fellow eye. We studied if the type of amblyopia (strabismus without anisometropia, anisometropia without strabismus, strabismus with anisometropia) had any influence on macular layer thickness values. Results There was significant difference between the amblyopic and fellow eyes in MRSE and AL in all subgroups. Comparing the amblyopic and fellow eyes, we found a statistically significant difference only in the thickness of the outer nuclear layer in the central region using linear mixed model analysis keeping AL and age under control (p = 0.032). There was no significant difference in interocular difference in the thickness of any macular layers between the subgroups with one-way between-groups ANCOVA while statistically controlling for interocular difference in AL and age. Conclusions According to our results there are subtle changes in amblyopic eyes affecting the outer nuclear layer of the fovea suggesting the possible involvement of the photoreceptors. However, further studies are warranted to support this hypothesis. PMID:24516641

  11. Brain morphological changes in adolescent and adult patients with anorexia nervosa.

    PubMed

    Seitz, J; Herpertz-Dahlmann, B; Konrad, K

    2016-08-01

    Gray matter (GM) and white matter (WM) volume loss occur in the brains of patients with acute anorexia nervosa (AN) and improve again upon weight restoration. Adolescence is an important time period for AN to begin. However, little is known about the differences between brain changes in adolescents vs adults. We used a meta-analysis and a qualitative review of all MRI studies regarding acute structural brain volume changes and their recovery in adolescents and adults with AN. 29 studies with 473 acute, 121 short-term weight-recovered and 255 long-term recovered patients with AN were included in the meta-analysis. In acute AN, GM and WM were reduced compared to healthy controls. Acute adolescent patients showed a significantly greater GM reduction than adults (-8.4 vs -3.1 %), the difference in WM (-4.0 vs -2.1 %) did not reach significance. Short-term weight-recovered patients showed a remaining GM deficit of 3.6 % and a non-significant WM reduction of 0.9 % with no age differences. Following 1.5-8 years of remission, GM and WM were no longer significantly reduced in adults (GM -0.4 %, WM -0.7 %); long-term studies for adolescents were scarce. The qualitative review showed that GM volume loss was correlated with cognitive deficits and three studies found GM regions, cerebellar deficits and WM to be predictive of outcome. GM and WM are strongly reduced in acute AN and even more pronounced in adolescence. Long-term recovery appears to be complete for adults while no conclusions can be drawn for adolescents, thus caution remains. PMID:27188331

  12. Morphological Brain Changes after Climbing to Extreme Altitudes—A Prospective Cohort Study

    PubMed Central

    Rummel, Christian; Hauf, Martinus; Hefti, Urs; Merz, Tobias Michael

    2015-01-01

    Background Findings of cerebral cortical atrophy, white matter lesions and microhemorrhages have been reported in high-altitude climbers. The aim of this study was to evaluate structural cerebral changes in a large cohort of climbers after an ascent to extreme altitudes and to correlate these findings with the severity of hypoxia and neurological signs during the climb. Methods Magnetic resonance imaging (MRI) studies were performed in 38 mountaineers before and after participating in a high altitude (7126m) climbing expedition. The imaging studies were assessed for occurrence of new WM hyperintensities and microhemorrhages. Changes of partial volume estimates of cerebrospinal fluid, grey matter, and white matter were evaluated by voxel-based morphometry. Arterial oxygen saturation and acute mountain sickness scores were recorded daily during the climb. Results On post-expedition imaging no new white matter hyperintensities were observed. Compared to baseline testing, we observed a significant cerebrospinal fluid fraction increase (0.34% [95% CI 0.10–0.58], p = 0.006) and a white matter fraction reduction (-0.18% [95% CI -0.32–-0.04], p = 0.012), whereas the grey matter fraction remained stable (0.16% [95% CI -0.46–0.13], p = 0.278). Post-expedition imaging revealed new microhemorrhages in 3 of 15 climbers reaching an altitude of over 7000m. Affected climbers had significantly lower oxygen saturation values but not higher acute mountain sickness scores than climbers without microhemorrhages. Conclusions A single sojourn to extreme altitudes is not associated with development of focal white matter hyperintensities and grey matter atrophy but leads to a decrease in brain white matter fraction. Microhemorrhages indicative of substantial blood-brain barrier disruption occur in a significant number of climbers attaining extreme altitudes. PMID:26509635

  13. Changes in lagoonal marsh morphology at selected northeastern Atlantic coast sites of significance to migratory waterbirds

    USGS Publications Warehouse

    Erwin, R.M.; Sanders, G.M.; Prosser, D.J.

    2004-01-01

    Five lagoonal salt marsh areas, ranging from 220 ha to 3,670 ha, were selected from Cape Cod, Massachusetts to the southern DelMarVa peninsula, Virginia, USA to examine the degree to which Spartina marsh area and microhabitats had changed from the early or mid- 1900s to recent periods. We chose areas based on their importance to migratory bird populations, agency concerns about marsh loss and sea-level rise, and availability of historic imagery. We georeferenced and processed aerial photographs from a variety of sources ranging from 1932 to 1994. Of particular interest were changes in total salt marsh area, tidal creeks, tidal flats, tidal and non-tidal ponds, and open water habitats. Nauset Marsh, within Cape Cod National Seashore, experienced an annual marsh loss of 0.40% (19% from 1947 to 1994) with most loss attributed to sand overwash and conversion to open water. At Forsythe National Wildlife Refuge in southern New Jersey, annual loss was 0.27% (17% from 1932 to 1995), with nearly equal attribution of loss to open water and tidal pond expansion. At Curlew Bay, Virginia, annual loss was 0.20% (9% from 1949 to 1994) and almost entirely due to perimeter erosion to open water. At Gull Marsh, Virginia, a site chosen because of known erosional losses, we recorded the highest annual loss rate, 0.67% per annum, again almost entirely due to erosional, perimeter loss. In contrast, at the southernmost site, Mockhorn Island Wildlife Management Area, Virginia, there was a net gain of 0.09% per annum (4% from 1949 to 1994), with tidal flats becoming increasingly vegetated. Habitat. implications for waterbirds are considerable; salt marsh specialists such as laughing gulls (Larus atricilla), Forster's terns (Sterna forsteri), black rail, (Laterallus jamaicensis), seaside sparrow (Ammodramus maritimus), and saltmarsh sharp-tailed sparrow (Ammodramus caudacutus) are particularly at risk if these trends continue, and all but the laughing gull are species of concern to state

  14. Changes in zooxanthellae density, morphology, and mitotic index in hermatypic corals and anemones exposed to cyanide.

    PubMed

    Cervino, J M; Hayes, R L; Honovich, M; Goreau, T J; Jones, S; Rubec, P J

    2003-05-01

    Sodium cyanide (NaCN) is widely used for the capture of reef fish throughout Southeast Asia and causes extensive fish mortality, but the effect of NaCN on reef corals remains debated. To document the impact of cyanide exposure on corals, the species Acropora millepora, Goniopora sp., Favites abdita, Trachyphyllia geoffrio, Plerogyra sp., Heliofungia actinformis, Euphyllia divisa, and Scarophyton sp., and the sea anemone Aiptasia pallida were exposed to varying concentrations of cyanide for varying time periods. Corals were exposed to 50, 100, 300, and 600 mg/l of cyanide ion (CN(-)) for 1-2 min (in seawater, the CN(-) forms hydrocyanic acid). These concentrations are much lower than those reportedly used by fish collectors. Exposed corals and anemones immediately retracted their tentacles and mesenterial filaments, and discharged copious amounts of mucus containing zooxanthellae. Gel electrophoreses techniques found changes in protein expression in both zooxanthellae and host tissue. Corals and anemones exposed to cyanide showed an immediate increase in mitotic cell division of their zooxenthellae, and a decrease in zooxanthellae density. In contrast, zooxanthellae cell division and density remained constant in controls. Histopathological changes included gastrodermal disruption, mesogleal degradation, and increased mucus in coral tissues. Zooxanthellae showed pigment loss, swelling, and deformation. Mortality occurred at all exposure levels. Exposed specimens experienced an increase in the ratio of gram-negative to gram-positive bacteria on the coral surface. The results demonstrate that exposure cyanide causes mortality to corals and anemones, even when applied at lower levels than that used by fish collectors. Even brief exposure to cyanide caused slow-acting and long-term damage to corals and their zooxanthellae. PMID:12735955

  15. Overexpression of Guanylate Cyclase Activating Protein 2 in Rod Photoreceptors In Vivo Leads to Morphological Changes at the Synaptic Ribbon

    PubMed Central

    López-Begines, Santiago; Fernández-Sánchez, Laura; Cuenca, Nicolás; Llorens, Jordi; de la Villa, Pedro; Méndez, Ana

    2012-01-01

    Guanylate cyclase activating proteins are EF-hand containing proteins that confer calcium sensitivity to retinal guanylate cyclase at the outer segment discs of photoreceptor cells. By making the rate of cGMP synthesis dependent on the free intracellular calcium levels set by illumination, GCAPs play a fundamental role in the recovery of the light response and light adaptation. The main isoforms GCAP1 and GCAP2 also localize to the synaptic terminal, where their function is not known. Based on the reported interaction of GCAP2 with Ribeye, the major component of synaptic ribbons, it was proposed that GCAP2 could mediate the synaptic ribbon dynamic changes that happen in response to light. We here present a thorough ultrastructural analysis of rod synaptic terminals in loss-of-function (GCAP1/GCAP2 double knockout) and gain-of-function (transgenic overexpression) mouse models of GCAP2. Rod synaptic ribbons in GCAPs−/− mice did not differ from wildtype ribbons when mice were raised in constant darkness, indicating that GCAPs are not required for ribbon early assembly or maturation. Transgenic overexpression of GCAP2 in rods led to a shortening of synaptic ribbons, and to a higher than normal percentage of club-shaped and spherical ribbon morphologies. Restoration of GCAP2 expression in the GCAPs−/− background (GCAP2 expression in the absence of endogenous GCAP1) had the striking result of shortening ribbon length to a much higher degree than overexpression of GCAP2 in the wildtype background, as well as reducing the thickness of the outer plexiform layer without affecting the number of rod photoreceptor cells. These results indicate that preservation of the GCAP1 to GCAP2 relative levels is relevant for maintaining the integrity of the synaptic terminal. Our demonstration of GCAP2 immunolocalization at synaptic ribbons at the ultrastructural level would support a role of GCAPs at mediating the effect of light on morphological remodeling changes of synaptic

  16. Functional consequences of age-related morphologic changes to pyramidal neurons of the rhesus monkey prefrontal cortex

    PubMed Central

    Coskren, Patrick J.; Luebke, Jennifer I.; Kabaso, Doron; Wearne, Susan L.; Yadav, Aniruddha; Rumbell, Timothy; Hof, Patrick R.; Weaver, Christina M.

    2014-01-01

    Layer 3 (L3) pyramidal neurons in the lateral prefrontal cortex (LPFC) of rhesus monkeys exhibit dendritic regression, spine loss and increased action potential (AP) firing rates during normal aging. The relationship between these structural and functional alterations, if any, is unknown. To address this issue, morphological and electrophysiological properties of L3 LPFC pyramidal neurons from young and aged rhesus monkeys were characterized using in vitro whole-cell patch-clamp recordings and high-resolution digital reconstruction of neurons. Consistent with our previous studies, aged neurons exhibited significantly reduced dendritic arbor length and spine density, as well as increased input resistance and firing rates. Computational models using the digital reconstructions with Hodgkin-Huxley and AMPA channels allowed us to assess relationships between demonstrated age-related changes and to predict physiological changes that have not yet been tested empirically. For example, the models predict that in both backpropagating APs and excitatory postsynaptic currents (EPSCs), attenuation is lower in aged versus young neurons. Importantly, when identical densities of passive parameters and voltage- and calcium-gated conductances were used in young and aged model neurons, neither input resistance nor firing rates differed between the two age groups. Tuning passive parameters for each model predicted significantly higher membrane resistance (Rm) in aged versus young neurons. This Rm increase alone did not account for increased firing rates in aged models, but coupling these Rm values with subtle differences in morphology and membrane capacitance did. The predicted differences in passive parameters (or parameters with similar effects) are mathematically plausible, but must be tested empirically. PMID:25527184

  17. Age-related changes in the morphology and protein expression of the thymus of healthy yaks (Bos grunniens).

    PubMed

    Zhang, Qian; Yang, Kun; Yangyang, Pan; He, Junfeng; Yu, Sijiu; Cui, Yan

    2016-06-01

    OBJECTIVE To evaluate age-related changes in the morphology and expression of cluster of differentiation 3 (CD3), S100 β, and caspase-3 of the thymus of healthy yaks (Bos grunniens). ANIMALS 15 healthy male yaks of various ages from highland plateaus. PROCEDURES Yaks were allocated to 3 groups on the basis of age (newborn [1 to 7 days old; n = 5], juvenile [5 to 7 months old, 5], and adult [3 to 4 years old; 5]) and euthanized. The thymus was harvested from each yak within 10 minutes after euthanasia. Morphological characteristics were assessed by histologic examination and transmission electron microscopy. Expression of CD3, S100 β, and caspase-3 mRNA and protein was measured by quantitative real-time PCR assay, Western blot analysis, and immunohistochemical staining. RESULTS As age increased, functional thymic tissue was replaced with adipose and connective tissues and the thymic capsule thickened. Expression of CD3 and S100 β mRNA and protein decreased with age, whereas expression of caspase-3 mRNA and protein increased with age. Immunohistochemical staining revealed that CD3-positive thymocytes were located within both the thymic cortex and medulla, S100 β-positive thymic dendritic cells were located in the corticomedullary junction and medulla, and caspase-3-positive thymocytes were diffusely scattered throughout the cortex and medulla. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that age-related thymic changes in yaks that live on highland plateaus were similar to those observed in humans and other mammals. Thus, yaks might serve as a model to study thymic immune system adaptations to high elevations. PMID:27227493

  18. Applications of a morphological scene change detection (MSCD) for visual leak and failure identification in process and chemical engineering

    NASA Astrophysics Data System (ADS)

    Tickle, Andrew J.; Harvey, Paul K.; Smith, Jeremy S.

    2010-10-01

    Morphological Scene Change Detection (MSCD) is a process typically tasked at detecting relevant changes in a guarded environment for security applications. This can be implemented on a Field Programmable Gate Array (FPGA) by a combination of binary differences based around exclusive-OR (XOR) gates, mathematical morphology and a crucial threshold setting. The additional ability to set up the system in virtually any location due to the FPGA makes it ideal for insertion into an autonomous mobile robot for patrol duties. However, security is not the only potential of this robust algorithm. This paper details how such a system can be used for the detection of leaks in piping for use in the process and chemical industries and could be deployed as stated in the above manner. The test substance in this work was water, which was pumped either as a liquid or as low pressure steam through a simple pipe configuration with holes at set points to simulate the leaks. These holes were situated randomly at either the center of a pipe (in order to simulate an impact to it) or at a joint or corner (to simulate a failed weld). Imagery of the resultant leaks, which were visualised as drips or the accumulation of steam, which where analysed using MATLAB to determine their pixel volume in order to calibrate the trigger for the MSCD. The triggering mechanism is adaptive to make it possible in theory for the type of leak to be determined by the number of pixels in the threshold of the image and a numerical output signal to state which of the leak situations is being observed. The system was designed using the DSP Builder package from Altera so that its graphical nature is easily comprehensible to the non-embedded system designer. Furthermore, all the data from the DSP Builder simulation underwent verification against MATLAB comparisons using the image processing toolbox in order to validate the results.

  19. In situ atomic force microscopy analysis of morphology and particle size changes in lithium iron phosphate cathode during discharge.

    PubMed

    Demirocak, Dervis Emre; Bhushan, Bharat

    2014-06-01

    Li-ion batteries offer great promise for future plug-in hybrid electric vehicles (PHEVs) and pure electric vehicles (EVs). One of the challenges is to improve the cycle life of Li-ion batteries which requires detailed understanding of the aging phenomenon. In situ techniques are especially valuable to understand aging since it allows monitoring the physical and chemical changes in real time. In this study, in situ atomic force microscopy (AFM) is utilized to study the changes in morphology and particle size of LiFePO4 cathode during discharge. The guidelines for in situ AFM cell design for accurate and reliable measurements based on different designs are presented. The effect of working electrode to counter electrode surface area ratio on cycling data of an in situ cell is also discussed. Analysis of the surface area change in LiFePO4 particles when the cell was cycled between 100% and 70% state of charge is presented. Among four particles analyzed, surface area increase of particles during Li intercalation of LiFePO4 spanned from 1.8% to 14.3% indicating the inhomogeneous nature of the cathode surface. PMID:24703680

  20. Patient satisfaction and penile morphology changes with postoperative penile rehabilitation 2 years after Coloplast Titan prosthesis.

    PubMed

    Pryor, Michael B; Carrion, Rafael; Wang, Run; Henry, Gerard

    2016-01-01

    A common complaint after inflatable penile prosthesis surgery is reduced penile length. We previously reported how using the Coloplast Titan inflatable penile prosthesis with aggressive new length measurement technique (NLMT) coupled with postoperative IPP rehabilitation of the implant for 1-year helped to improve patient satisfaction and erectile penile measurements. This is a 2 years follow-up of a prospective, three-center, study of 40 patients who underwent Titan prosthesis placement, with new length measurement technique for erectile dysfunction. Patient instructions were to inflate daily for 6 months and then inflate maximally for 1-2 h daily for 6-24 months. Fifteen penile measurements were taken before and immediately after surgery and at follow-up visits. Measurement changes were improved at 24 months as compared to immediately postoperative and at 12 months. 67.8% of subjects were satisfied with their length at 2 years, and 77% had perceived penile length that was longer (30.8%) or the same (46.2%) as prior to the surgery. 64.3% and 17.9% of subjects had increased and unchanged satisfaction, respectively, with penile length as compared to prior to penile implant surgery. All but one subject (96.5%) was satisfied with the overall function of his implant. This study suggests using the Coloplast Titan with aggressive cylinder sizing, and a postoperative penile rehabilitation inflation protocol can optimize patient satisfaction and erectile penile measurements at 2 years postimplant. PMID:26459782

  1. Bactericidal thurincin H causes unique morphological changes in Bacillus cereus F4552 without affecting membrane permeability.

    PubMed

    Wang, Gaoyan; Feng, Guoping; Snyder, Abigail B; Manns, David C; Churey, John J; Worobo, Randy W

    2014-08-01

    Thurincin H is an antilisterial bacteriocin produced by Bacillus thuringiensis SF361. It exhibits inhibitory activity against a wide range of Gram-positive foodborne pathogens and spoilage bacteria including Listeria monocytogenes, B. cereus, and B. subtilis. This hydrophobic, anionic bacteriocin folds into a hairpin structure maintained by four pairs of unique sulfur to α-carbon thioether bonds. As its hydrophobicity and structure are quite different from most archived bacteriocins, this study aimed to elucidate its mode of action and compare it with the mechanisms of other well-characterized bacteriocins. The results indicated that, although bactericidal to B. cereus F4552, thurincin H did not lead to optical density reduction or detectable changes in cell membrane permeability. B. cereus F4552 imaged by scanning electron microscopy after treatment with thurincin H at 32 × MIC showed regular rod-shaped cells, while only cells treated with thurincin H at the elevated levels of 256 × MIC showed loss of cell integrity and rigidity. Both concentrations caused greater than 99% of cell viability reduction. In contrast, nisin caused significant cell membrane permeability at concentration as low as 2 × MIC. These results indicated a difference in the mode of action for thurincin H compared with the generalized pore-forming mechanism of many lantibiotics, such as nisin. PMID:24891232

  2. Changes in growth and morphology of the condyle following mandibular distraction in minipigs: Overloading or Underloading?

    PubMed Central

    Rafferty, Katherine L.; Sun, Zongyang; Egbert, Mark; Bakko, Daniel W.; Herring, Susan W.

    2007-01-01

    Objective: Loading of temporomandibular tissues during mandibular distraction may cause changes in condylar growth and cartilage thickness. This study examines the effects of distraction on the condyle in a large animal model by explicitly measuring growth and in vivo loading. Design: Unilateral mandibular distraction was carried out on twenty growing minipigs divided into three groups. One group underwent distraction but not consolidation, whereas the other two groups were allowed a period of consolidation of either one or two weeks. Animals received fluorochrome and 5-bromo-2'-deoxyuridine (BrdU) labeling and masticatory strain was measured from the condylar neck. Condylar strain was also recorded in an age-matched sample of eight animals that received no distraction surgery. Immunohistochemical procedures were used to identify dividing prechondroblasts and histological analysis was used to measure mineral apposition rate, count dividing cells, and measure the thickness of condylar cartilage. Results: Strain magnitude, particularly compressive strain, was much larger on the non-distraction side compared to the distraction side condyle. Compared to normal loading levels, the distraction side condyle was underloaded whereas the condyle on the intact side was overloaded. Mineral apposition and cartilage thickness were greater on the distraction side condyle compared to the opposite side. Differences between the sides were most pronounced in the group with no consolidation and became progressively reduced with consolidation time. Conclusions: Increased mineralization and cartilage thickness on the distraction side condyle is associated with reduced, not increased loading, perhaps because of disruption of the distraction side masseter muscle. PMID:17573035

  3. [The morphological changes in the myocardial tissue after sudden cardiac death from alcoholic cardiomyopathy].

    PubMed

    Sokolova, O V

    2016-01-01

    This paper was designed to report the results of the retrospective analysis of the protocols of 180 forensic medical autopsy sections stored in the archives of Sankt-Petersburg Bureau of Forensic Medical Expertise and the data of the histological studies of myocardial tissues obtained after sudden cardiac death from alcoholic cardiomyopathy. The study revealed the following most pathognomonic histological criteria for alcoholic heart lesions: the alternation of hypertrophic and atrophic cardiomyocytes in the state of severe parenchymatous degeneration, pronounced mesenchymal fatty dystrophy in combination with pathological changes of the vascular walls (vascular wall plasmatization), sub-endothelial accumulation of the PAS-positive tissue compounds, microcirculatory disorders in the form of erythrocyte stasis with the manifestations of the blood "sludge" phenomenon, and precapillary fibrosis. The signs of severe parenchymatous and stromal vascular dystrophy of the myocardial histohematic barrier (HHB) are supposed to reflect the toxic effects of ethanol and its metabolites that are directly involved in the mechanisms underlying the disturbances of intracellular metabolism and dyscirculatory events leading to the development of heart muscle hypoxia. PMID:27030089

  4. Parallel changes in genital morphology delineate cryptic diversification of planktonic nudibranchs.

    PubMed

    Churchill, Celia K C; Alejandrino, Alvin; Valdés, Angel; Foighil, Diarmaid O

    2013-08-22

    The relative roles of geographical and non-geographical barriers in the genesis of genetic isolation are highly debated in evolutionary biology, yet knowing how speciation occurs is essential to our understanding of biodiversity. In the open ocean, differentiating between the two is particularly difficult, because of the high levels of gene flow found in pelagic communities. Here, we use molecular phylogenetics to test the hypothesis that geography is the primary isolating mechanism in a clade of pelagic nudibranchs, Glaucinae. Our results contradict allopatric expectations: the cosmopolitan Glaucus atlanticus is panmictic, whereas the Indo-Pacific Glaucus marginatus contains two pairs of cryptic species with overlapping distributions. Within the G. marginatus species complex, a parallel reproductive change has occurred in each cryptic species pair: the loss of a bursa copulatrix. Available G. marginatus data are most consistent with non-geographical speciation events, but we cannot rule out the possibility of allopatric speciation, followed by iterative range extension and secondary overlap. Irrespective of ancestral range distributions, our results implicate a central role for reproductive character differentiation in glaucinin speciation-a novel result in a planktonic system. PMID:23825213

  5. Physiological and morphological changes in Salix viminalis L. as a result of plant exposure to copper.

    PubMed

    Gąsecka, Monika; Mleczek, Mirosław; Drzewiceka, Kinga; Magdziak, Zuzanna; Rissmann, Iwona; Chadzinikolau, Tamara; Golinski, Piotr

    2012-01-01

    The aim of this study was to assess the response of Salix viminalis L. under model conditions to different copper concentrations and, as a consequence, potential application of the experimental results in decontamination of water with heavy metal ions (phytoaccumlation). The 14-day experiment was conducted on one-year-old cuttings of Salix viminalis L. 'Cannabina' exposed, in a phytotron, to six different copper levels in hydroponic pots. The results showed that the capacity to accumulate heavy metals was of the following order: roots > rods > shoots > leaves. The linear relationships between the accumulation efficiency of particular Salix parts were confirmed. Together with an increase in copper sorption in above-ground organs, a decrease was observed in root biomass and the length of roots, shoots and leaves. The release of low molecular weight organic acids into solution was different under various Cu levels. Glucose, fructose and sucrose contents in leaves of Salix in all treatments were higher than in control plants. Higher concentration of sugars (4 times higher compared to the control) was detected for fructose in a 2 mM Cu treatment. The total phenolics content rapidly increased only at 3 mM Cu level. Free and total salicylic acid and the glutathione contents in plants treated with copper in relation to the control were always higher and changed with increasing concentration of copper ions in the medium. PMID:22375537

  6. Massage-induced morphological changes of dense connective tissue in rat's tendon.

    PubMed

    Kassolik, Krzysztof; Andrzejewski, Waldemar; Dziegiel, Piotr; Jelen, Michal; Fulawka, Lukasz; Brzozowski, Marcin; Kurpas, Donata; Gworys, Bohdan; Podhorska-Okolow, Marzenna

    2013-01-01

    The aim of the experiment was to determine if possible changes in connective tissue induced by massage could have a positive effect justifing the use of massage in all post-traumatic connective tissue conditions, e.g. tendon injuries. The investigations were performed in a group of 18 Buffalo rats. The rats were divided into two groups (experimental and control). To standardize the massage procedure, it was performed with an algometer probe of 0.5 cm2 with constant pressure force of 1 kG (9,81 N). To analyse the number and diameter of collagen fibrils, two electron micrographs were performed for each rat of the collected segments of tendons of rat tail lateral extensor muscle. After image digitalization and calibration, the measurements were carried out using iTEM 5.0 software. The number of fibrils, their diameter and area were measured in a cross-sectional area. An increase of the number of collagen fibrils was observed in the tendons of massaged animals compared to the control group. Our study demonstrated that massage may cause a beneficial effect on metabolic activity of tendon's fibroblasts and, in consequence, may be applied for more effective use of massage for the prevention of tendon injury as well as after the injury has occurred. (Folia Histochemica et Cytobiologica 2013, Vol. 51, No. 1, 103-106). PMID:23690224

  7. Patient satisfaction and penile morphology changes with postoperative penile rehabilitation 2 years after Coloplast Titan prosthesis

    PubMed Central

    Pryor, Michael B; Carrion, Rafael; Wang, Run; Henry, Gerard

    2016-01-01

    A common complaint after inflatable penile prosthesis surgery is reduced penile length. We previously reported how using the Coloplast Titan inflatable penile prosthesis with aggressive new length measurement technique (NLMT) coupled with postoperative IPP rehabilitation of the implant for 1-year helped to improve patient satisfaction and erectile penile measurements. This is a 2 years follow-up of a prospective, three-center, study of 40 patients who underwent Titan prosthesis placement, with new length measurement technique for erectile dysfunction. Patient instructions were to inflate daily for 6 months and then inflate maximally for 1–2 h daily for 6–24 months. Fifteen penile measurements were taken before and immediately after surgery and at follow-up visits. Measurement changes were improved at 24 months as compared to immediately postoperative and at 12 months. 67.8% of subjects were satisfied with their length at 2 years, and 77% had perceived penile length that was longer (30.8%) or the same (46.2%) as prior to the surgery. 64.3% and 17.9% of subjects had increased and unchanged satisfaction, respectively, with penile length as compared to prior to penile implant surgery. All but one subject (96.5%) was satisfied with the overall function of his implant. This study suggests using the Coloplast Titan with aggressive cylinder sizing, and a postoperative penile rehabilitation inflation protocol can optimize patient satisfaction and erectile penile measurements at 2 years postimplant. PMID:26459782

  8. Characteristics and short-term changes of the Po Delta seafloor morphology through high-resolution bathymetric and backscatter data

    NASA Astrophysics Data System (ADS)

    Madricardo, Fantina; Bosman, Alessandro; Kruss, Aleksandra; Remia, Alessandro; Correggiari, Anna; Fogarin, Stefano; Romagnoli, Claudia; Moscon, Giorgia

    2016-04-01

    River deltas are highly dynamical and valuable environments and often undergo strong natural and human-induced actions that need constant monitoring. Whereas remote sensing observations of the sub-aerial part of the delta are very important for the assessment of the morphological changes over long time scales (years-decades), the short time-scale evolution of the submerged part of the system remains often undetermined. In particular, the shallow-water submarine pro-delta front is commonly characterized by active depositional and erosional processes. This area is crucial for the understanding of the fluvial and coastal dynamics. In this study, we applied geophysical investigations to characterize the very shallow-water area of the Po river delta in the northern Adriatic Sea. The modern Po delta is the result of increased sediment flux derived from both climate change (Little Ice Age) and human impact (deforestation and diversion and construction of artificial levees) and in recent years is suffering erosion. Here, we present the results of two high-resolution multibeam echosounder surveys carried out in June 2013 and in September 2014 on the Po river mouth and delta front in the framework of the Ritmare Project. The Po delta front, as other modern deltas, has a complicated morphology, consisting of multiple terminal distributary channels, subaqueous levee deposits, and mouth bars. The high-resolution bathymetric data show that the prodelta slope has a curved shape with an overall southward asymmetry of the submerged delta due to prevalent longshore currents. The 2013 bathymetric map highlights a number of sedimentary features, such as depositional bars, radiating in the prodelta slope with an asymmetric section, with steeper southward lee side. The new bathymetric map collected in 2014 shows impressive changes: in correspondence with the depositional lobes, we observed extensive collapse depressions with bathymetric changes of over 1 m in 15 months and widespread

  9. Detection of morphological changes in cliff face surrounding a waterfall using terrestrial laser scanning and unmanned aerial system

    NASA Astrophysics Data System (ADS)

    Hayakawa, Yuichi S.; Obanawa, Hiroyuki

    2015-04-01

    Waterfall or bedrock knickpoint appears as an erosional front in bedrock rivers forming deep v-shaped valley downstream. Following the rapid fluvial erosion of waterfall, rockfalls and gravita-tional collapses often occur in surrounding steep cliffs. Although morphological changes of such steep cliffs are sometimes visually observed, quantitative and precise measurements of their spatio-temporal distribution have been limited due to the difficulties in direct access to such cliffs if with classical measurement methods. However, for the clarification of geomorphological processes oc-curring in the cliffs, multi-temporal mapping of the cliff face at a high resolution is necessary. Re-mote sensing approaches are therefore suitable for the topographic measurements and detection of changes in such inaccessible cliffs. To achieve accurate topographic mapping of cliffs around a wa-terfall, here we perform multi-temporal terrestrial laser scanning (TLS), as well as structure-from-motion multi-view stereo (SfM-MVS) photogrammetry based on unmanned aerial system (UAS). The study site is Kegon Falls in central Japan, having a vertical drop of surface water from top of its overhanging cliff, as well as groundwater outflows from its lower portions. The bedrock is composed of alternate layers of andesite lava and conglomerates. Minor rockfalls in the cliffs are often ob-served by local people. The latest major rockfall occurred in 1986, causing ca. 8-m upstream propa-gation of the waterfall lip. This provides a good opportunity to examine the changes in the surround-ing cliffs following the waterfall recession. Multi-time point clouds were obtained by TLS measure-ment over years, and the three-dimensional changes of the rock surface were detected, uncovering the locus of small rockfalls and gully developments. Erosion seems particularly frequent in relatively weak the conglomerates layer, whereas small rockfalls seems to have occurred in the andesite layers. Also, shadows in the

  10. Development and morphological changes in the vaginal closure membrane throughout gestation in Galea spixii (Rodentia: Caviidae).

    PubMed

    Dos Santos, Amilton Cesar; Oliveira, Gleidson Benevides; Viana, Diego Carvalho; Oliveira, Franceliusa Delys; Silva, Renata Dos Santos; Rici, Rose Eli Grassi; de Oliveira, Moacir Franco; de Assis-Neto, Antônio Chaves

    2016-05-01

    Present research was carried out in order to perform the monitoring of development, recognizes the type of tissue and describes histological and cellular changes of the vaginal closure membrane (VCM) throughout pregnancy in Galea spixii. The results showed that at 20 days of gestation (DG), the VCM occludes completely the external vaginal ostium. Microscopically, the VCM presented juxtaposed cells, derived from the stratum germinative of the stratified epithelium of vaginal mucosa at 20 DG and areas with cell clusters with the presence of intercellular spaces in the final stages of pregnancy (40-50 DG). At 0 DG, the stratified epithelium of vaginal mucosa presented all strata but at 20 DG presented stratified epithelium without the stratum corneum and stratum granular and showed communicant junctions by desmosomes and interdigitations in the cell membrane compound the VCM. Gradually from 40 to 50 DG the stratum germinative became barely perceptible. Many cells showed apoptotic nuclei and emerged many intercellular spacing. So, the interdigitations and desmosomes were not observed. Here, it was demonstrated for the first time that the VCM is formed after the extinction of the stratum granular and corneum of the vaginal mucosa epithelium, with the proliferation of the cells of stratum germinative and communication and junction through desmosomes and interdigitations of these cells. At the end of pregnancy, cellular apoptosis; the spread of stratum germinative; and, absence of cellular communication and junction may be responsible for the weakening of the VCM and may assist the process of rupture of this membrane. Microsc. Res. Tech. 79:359-364, 2016. © 2016 Wiley Periodicals, Inc. PMID:26873391

  11. Morphologic changes associated with functional adaptation of the navicular bone of horses.

    PubMed

    Bentley, V A; Sample, S J; Livesey, M A; Scollay, M C; Radtke, C L; Frank, J D; Kalscheur, V L; Muir, P

    2007-11-01

    Failure of functional adaptation to protect the skeleton from damage is common and is often associated with targeted remodeling of bone microdamage. Horses provide a suitable model for studying loading-related skeletal disease because horses are physically active, their exercise is usually regulated, and adaptive failure of various skeletal sites is common. We performed a histologic study of the navicular bone of three groups of horses: (1) young racing Thoroughbreds (n = 10); (2) young unshod ponies (n = 10); and (3) older horses with navicular syndrome (n = 6). Navicular syndrome is a painful condition that is a common cause of lameness and is associated with extensive remodeling of the navicular bone; a sesamoid bone located within the hoof which articulates with the second and third phalanges dorsally. The following variables were quantified: volumetric bone mineral density; cortical thickness (Ct.Th); bone volume fraction, microcrack surface density; density of osteocytes and empty lacunae; and resorption space density. Birefringence of bone collagen was also determined using circularly polarized light microscopy and disruption of the lacunocanalicular network was examined using confocal microscopy. Remodeling of the navicular bone resulted in formation of transverse secondary osteons orientated in a lateral to medial direction; bone collagen was similarly orientated. In horses with navicular syndrome, remodeling often led to the formation of intracortical cysts and development of multiple tidemarks at the articular surface. These changes were associated with high microcrack surface density, low bone volume fraction, low density of osteocytes, and poor osteocyte connectivity. Empty lacunae were increased in Thoroughbreds. Resorption space density was not increased in horses with navicular syndrome. Taken together, these data suggest that the navicular bone may experience habitual bending across the sagittal plane. Consequences of cumulative cyclic loading in

  12. Developmental changes in membrane excitability and morphology of neurons in the nucleus angularis of the chicken

    PubMed Central

    Fukui, Iwao; Ohmori, Harunori

    2003-01-01

    In order to understand how sound intensity information is extracted and processed in the auditory nuclei, we investigated the neuronal excitability in the nucleus angularis (NA) of the chicken (P0–5) and the chicken embryo (E16–21). In embryos, neurons fired basically in three patterns in response to current injections: the onset pattern (19 %), the tonic pattern (52 %) and the pause pattern (29 %). After hatching, neurons fired either in the tonic pattern (83 %) or in the onset pattern (17 %). In both pre- and post-hatch periods, multiple firing neurons (tonic and pause) increased the maximum rate of rise of the action potential 2.6-fold, the fall 3.9-fold, and the maximum firing frequency 4-fold, and shifted the threshold potential to be more negative. After hatching, the firing frequency of tonic neurons reached a maximum at about 650 Hz. Application of TEA (1 mm) reduced the firing frequency, broadened action potentials and reduced the maximum rate of fall, but the threshold current was not changed. Dendrotoxin-I (DTX, 100 nm) reduced the threshold current. Application of DTX induced the onset neuron to fire repetitively. Branching patterns of auditory nerve fibres (ANFs) in NA were visualized by labelling with 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (Di-I) placed within the cochlea. Di-I placed near the apex of the cochlea labelled the ventral part of the NA, and Di-I placed in the base labelled the dorso-lateral part. Tonic neurons labelled with biocytin extended dendrites in parallel with the projection of ANFs in the nucleus after hatching. ANF activity of a limited range of characteristic sound frequencies is thought to be extracted by tonic neurons and encoded into firing frequencies proportional to the strength of the input. PMID:12576492

  13. Changes induced by prenatal stress in behavior and brain morphology: can they be prevented or reversed?

    PubMed

    Weinstock, Marta

    2015-01-01

    This chapter presents a critical analysis of the behavioral alterations reported in the offspring of women exposed to stress and/or depression during pregnancy and the neurochemical and structural changes underlying them. Among the alterations attributed to prenatal stress in humans and experimental rats of both sexes is impaired regulation of the hypothalamic-pituitary-adrenal (HPA) axis, anxiety and exaggerated fear of novelty, and decreased social interaction. Learning and attention deficits are more prevalent in boys and male rats. Fear of novelty and anxiety are associated with enlargement of the amygdala and its corticotropin-releasing factor content, and decreased socialization, with lower oxytocin activity in the amygdala. Learning deficits are associated with a decrease in neurogenesis, dendritic complexity, and spine number in the dorsal hippocampus. Fostering prenatally stressed (PS) pups onto control mothers prevents the dysregulation of the HPA axis and heightened anxiety, indicating a role for postnatal factors in their etiology. By contrast, learning impairment and decreased socialization are not affected by this fostering procedure and are therefore prenatally mediated.In spite of their widespread use in depressed pregnant women, selective serotonin reuptake inhibitor (SSRI) antidepressants do not normalize the behavior of their children. When administered during gestation to stressed rats, SSRIs do not reduce anxiety or learning deficits in their offspring. Moreover, when given to unstressed mothers, SSRIs induce anxiety in the offspring. The detrimental effect of SSRIs may result from inhibition of the serotonin transporter exposing the brain to excess amounts of 5-hydroxytryptamine (5-HT) at a critical time during fetal development. PMID:25287533

  14. Morphological Changes of Tidal Headland Connected Sandbanks infered from Time Lapse Multibeam Surveys

    NASA Astrophysics Data System (ADS)

    Schmitt, T.; Mitchell, N. C.; Ramsay, T.

    2003-04-01

    Sandbanks are commonly found near irregularities of the coastline. A popular hypothesis for their origin states that interaction of tidal currents with a coastal headland induces vortices in residual currents downstream of it. Such vortices lead to the development and maintenance of such sandbanks (Pingree and Maddock, 1979). We have surveyed two headland-connected sandbanks in the Bristol Channel (South Wales, UK), the Helwick and the Nash Sand Banks, using a new Reson Seabat 8101 multibeam echo-sounder owned by Cardiff University. Around the Helwick sand bank, we surveyed an area encompassing the connection of the bank with the south Gower coast, the headland (Port Eynon Point) and the offshore part of a bay (Port Eynon Bay) to infer the distribution of bedforms and to test the above hypothesis. On the southern side of the bank, close to its connection with the coastline, an area has been surveyed on two occasions separated by a year to infer the ability of multibeam sonar to track the mobility of the bedforms around the bank. Sandwaves of ~5 m high and 100-200 m spacing are superimposed on the bank. Their lee sides, on the southern side of the bank, point to the west, indicating an ebb-dominated sediment movement, whereas their shape changes towards the crest of the bank to a more symmetrical form. On the northern side of the bank their orientations indicate that they are dominated by flood flow. Hence the sandwaves orientations suggest a circular flow pattern around the bank, as expected. This study forms part of a time-series comparison of successive multibeam surveys of this area. Preliminary comparisons of the two first surveys (September 2001-August 2002) indicates a differential migration of the bedforms of ~40m on the northern flank of the bank towards the east and ~80m on the southern side towards the west. Such migration of the sandwaves is similar to the direction of the residual currents downstream of the headland mentioned by the Pingree and Maddock

  15. Improving understanding of near-term barrier island evolution through multi-decadal assessment of morphologic change

    USGS Publications Warehouse

    Lentz, Erika E.; Hapke, Cheryl J.; Stockdon, Hilary F.; Hehre, Rachel E.

    2013-01-01

    Observed morphodynamic changes over multiple decades were coupled with storm-driven run-up characteristics at Fire Island, New York, to explore the influence of wave processes relative to the impacts of other coastal change drivers on the near-term evolution of the barrier island. Historical topography was generated from digital stereo-photogrammetry and compared with more recent lidar surveys to quantify near-term (decadal) morphodynamic changes to the beach and primary dune system between the years 1969, 1999, and 2009. Notably increased profile volumes were observed along the entirety of the island in 1999, and likely provide the eolian source for the steady dune crest progradation observed over the relatively quiescent decade that followed. Persistent patterns of erosion and accretion over 10-, 30-, and 40-year intervals are attributable to variations in island morphology, human activity, and variations in offshore bathymetry and island orientation that influence the wave energy reaching the coast. Areas of documented long-term historical inlet formation and extensive bayside marsh development show substantial landward translation of the dune–beach profile over the near-term period of this study. Correlations among areas predicted to overwash, observed elevation changes of the dune crestline, and observed instances of overwash in undeveloped segments of the barrier island verify that overwash locations can be accurately predicted in undeveloped segments of coast. In fact, an assessment of 2012 aerial imagery collected after Hurricane Sandy confirms that overwash occurred at the majority of near-term locations persistently predicted to overwash. In addition to the storm wave climate, factors related to variations within the geologic framework which in turn influence island orientation, offshore slope, and sediment supply impact island behavior on near-term timescales.

  16. Thermal alteration and morphological changes of sound and demineralized primary dentin after Er:YAG laser ablation.

    PubMed

    Brandão, Cristina Bueno; Contente, Marta Maria Martins Giamatei; De Lima, Fabrício Augusto; Galo, Rodrigo; Corrêa-Afonso, Alessandra Marques; Bachmann, Luciano; Borsatto, Maria Cristina

    2012-02-01

    The purpose of this study was to assess the influence of Er:YAG laser pulse repetition rate on the thermal alterations occurring during laser ablation of sound and demineralized primary dentin. The morphological changes at the lased areas were examined by scanning electronic microscopy (SEM). To this end, 60 fragments of 30 sound primary molars were selected and randomly assigned to two groups (n = 30); namely A sound dentin (control) and B demineralized dentin. Each group was divided into three subgroups (n = 10) according to the employed laser frequencies: I-4 Hz; II-6 Hz, and III-10 Hz. Specimens in group B were submitted to a pH-cycling regimen for 21 consecutive days. The irradiation was performed with a 250 mJ pulse energy in the noncontact and focused mode, in the presence of a fine water mist at 1.5 mL/min, for 15 s. The measured temperature was recorded by type K thermocouples adapted to the dentin wall relative to the pulp chamber. Three samples of each group were analyzed by SEM. The data were submitted to the nonparametric Kruskal-Wallis test and to qualitative SEM analysis. The results revealed that the temperature increase did not promote any damage to the dental structure. Data analysis demonstrated that in group A, there was a statistically significant difference among all the subgroups and the temperature rise was directly proportional to the increase in frequency. In group B, there was no difference between subgroup I and II in terms of temperature. The superficial dentin observed by SEM displayed irregularities that augmented with rising frequency, both in sound and demineralized tissues. In conclusion, temperature rise and morphological alterations are directly related to frequency increment in both demineralized and sound dentin. PMID:21761493

  17. Changes in small intestinal morphology and digestive enzyme activity with oral administration of copper-loaded chitosan nanoparticles in rats.

    PubMed

    Han, Xin-Yan; Du, Wen-Li; Huang, Qi-Chun; Xu, Zi-Rong; Wang, Yi-Zheng

    2012-03-01

    The experiment was conducted to evaluate the effect of copper-loaded chitosan nanoparticles on the small intestinal morphology and activities of digestive enzyme and mucosal disaccharase in rats. Forty male Sprague-Dawley rats, with average body weight of 82 g, were randomly allotted to five groups (n = 8). All rats were received a basal diet (control) or the same basal diet added with 80 mg/kg BW CuSO(4), 80 mg/kg BW chitosan (CS-I), 80 mg/kg BW copper-loaded chitosan nanoparticles (CSN-I), 160 mg/kg BW copper-loaded chitosan nanoparticles (CSN-II), respectively. The experiment lasted 21 days. The results showed that the villus heights of the small intestinal mucosa in groups CSN-I and CSN-II were higher than those of the control, group CuSO(4) or CS-I. The crypt depth of duodenum and ileum mucosa in group CSN-I or CSN-II was depressed. Compared with the control, there were no significant effects of CuSO(4) or CS-I on the villus height and crypt depth of small intestinal mucosa. Supplementation with CSN improved the activities of trypsin, amylase and lipase in the small intestinal contents and maltase, sucrase and lactase of duodenum, jejunum, and ileum mucosa while there were no significant effects of CuSO(4) on the digestive enzyme activities of the small content compared with the control. The results indicated that intestinal morphology, activities of digestive enzyme in digesta and mucosal disaccharase were beneficially changed by treatment of copper-loaded chitosan nanoparticles. PMID:21882065

  18. Repeated fluvoxamine treatment recovers juvenile stress-induced morphological changes and depressive-like behavior in rats.

    PubMed

    Lyttle, Kerise; Ohmura, Yu; Konno, Kohtarou; Yoshida, Takayuki; Izumi, Takeshi; Watanabe, Masahiko; Yoshioka, Mitsuhiro

    2015-08-01

    Human studies have suggested that early life stress such as child abuse could enhance susceptibility to depressive disorders. Moreover, the abnormalities of the prefrontal cortex have been associated with depression. Although clinical studies have implied the negative effects of early life stress on brain development, the causality and the detailed morphogenetic changes has not been clearly elucidated. In the present study, we determined the effect of juvenile stress exposure on the presentation of depressive-like behavior and the neural mechanisms involved using a rodent model. Rat pups were exposed to footshock stress during postnatal days 21-25 followed by repeated oral administration of fluvoxamine (0 or 10mg/kg/d × 14 days), which is a selective serotonin reuptake inhibitor. At the postadolescent stage forced swim test assessment of depressive-like behavior and Golgi-Cox staining of medial prefrontal cortex pyramidal neurons followed by morphological analyses were carried out. Post-adolescent behavioral and morphological studies identified the presentation of increased depressive-like behaviors and reduced spine densities and dendritic lengths of layer II/III pyramidal neuron in the infralimbic cortex, but not in the prelimbic cortex of rats exposed to juvenile stress. Repeated fluvoxamine treatment recovered the increased depressive-like behavior and reduced spine densities/dendritic lengths observed in rats exposed to footshock stress. Cortical thicknesses in the infralimbic cortex and prelimbic cortex were also reduced by juvenile stress, but these reductions were not recovered by fluvoxamine treatment. The results demonstrate cortical sensitivities to stress exposures during the juvenile stage which mediate behavioral impairments, and provide a clue to find therapeutics for early life stress-induced emotional dysfunctions. PMID:25960352

  19. Morphological and physiological changes exhibited by a Cd-resistant Dictyosphaerium chlorelloides strain and its cadmium removal capacity.

    PubMed

    Bartolomé, M C; Cortés, A A; Sánchez-Fortún, A; Garnica-Romo, M G; Sánchez-Carrillo, S; Sánchez-Fortún, Sebastián

    2016-12-01

    Changes induced on freshwater microalga Dictyosphaerium chlorelloides (Dc(wt)) acclimated in the laboratory until their survival in culture media enriched with cadmium 100 µM have been studied. Cadmium removal by living cells of this Cd-resistant (Dc(CdR100)) strain was tested in cultures exposed to 100 µM Cd during 30 days. Cell dimensions were measured under light microscopy, and cell growth was studied. Photosynthetic yield (ΦPSII) was analyzed and the photosynthetic oxygen development and respiration response was obtained. Results show that Dc(CdR100) strain exhibited significant cell morphology changes in comparison to Dc(wt) cells, which affected both surface area and cell biovolume. Malthusian fitness analysis showed that Dc(CdR100) strain living in Cd-enriched culture had developed a lower capacity of nearly 50% growth, and its photosynthetic oxygen development and respiration response were significantly reduced in both light and dark photosynthetic phases. Dc(CdR100) strain showed a very high capacity to remove cadmium from the aquatic environment (over 90%), although most of the removed heavy metal (≈70%) is adhered to the cell wall. These specific characteristics of Dc(CdR100) cells suggest the possibility of using this strain in conjunction with Dc(wt) strain as bioelements into a dual-head biosensor, and in bioremediation processes on freshwater polluted with Cd. PMID:27222159

  20. Morphologic changes in livers of hamsters treated with high doses of ursodeoxycholic acid: correlation with bile acids in bile.

    PubMed

    Mamianetti, A; Konopka, H F; Lago, N; Vescina, C; Scarlato, E; Carducci, C N

    1994-01-01

    The effects of high doses of ursodeoxycholic acid on bile acid composition and the liver morphology was examined in 60 male Syrian golden hamsters. The animals were allocated to five groups: I, control; II and IV received 0.5 g and 1 g of ursodeoxycholic acid per 100 g of standard diet respectively over 30 days and III and V received 0.5 g and 1 g of ursodeoxycholic acid per 100 g of standard diet respectively over 60 days. Bile acids were determined by high performance liquid chromatography. In all treated groups there was a significant increase in chenodeoxycholic and lithocholic acid in the bile. The mean glyco/tauro ratio was significantly higher than in the control group, reaching values > 1 for individual bile acids, except for lithocholic acid values which remained < 1. Under light microscopy, the livers of the hamsters showed damage which was dose/time related, namely portal inflammatory infiltrate, bile duct proliferation, cholestasis, fat infiltration and necrosis. Electron microscopy revealed pronounced changes starting with microvilli edema and extending to canalicular membrane destruction and necrosis. The changes observed in the relation glyco/tauro lithocholic acids, may be due to defence mechanisms to avoid hepatotoxicity. The hepatotoxicity resulting from ursodeoxycholic acid administration is presumed to be due primarily to lithocholic acid or some lithocholic acid metabolite. PMID:8058592

  1. Morphological changes of wrasse sperm axoneme after their motility initiation observed with use of atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Shimizu, Hideaki; Majima, Toshikazu; Takai, Hiroyuki; Inaba, Kazuo; Tomie, Toshihisa

    1995-03-01

    The sperm of bambooleaf wrasse, a marine teleost, are immotile when they are diluted in a solution isotonic to the seminal plasma, but they begin to swim when they are suspended in sea water. What changes arise in morphology of the sperm cell after the motility initiation? The semen collected from the abdomen of a matured wrasse was mixed with either thinned sea water or sea water. A drop of the same specimen was placed on a cleaned silicon wafer, respectively. After fixed chemically, they were rinsed with distilled water and dried naturally in room temperature. These samples were examined carefully with use of an atomic force microscopy. Although the axonemes of intact sperms were found to be crushed as if the axonemes were cut open along doublet microtubules. The motility initiated sperm was strong enough to resist the force caused by surface tension of water in the drying process and could maintain the structure of the axoneme. These experimental facts suggest that the binding characteristics in the structure of the axoneme after the initiation of the motility were clearly changed stronger that before.

  2. Morphological changes of skeletal muscle in spinal and bulbar muscular atrophy (SBMA), Kennedy's disease: a case report.

    PubMed

    Acewicz, Albert; Wierzba-Bobrowicz, Teresa; Lewandowska, Eliza; Sienkiewicz-Jarosz, Halina; Sulek, Anna; Antczak, Jakub; Rakowicz, Maria; Ryglewicz, Danuta

    2015-01-01

    Spinal and bulbar muscular atrophy (SBMA, Kennedy's disease) is an X-linked recessive disease affecting lower motor neurons. In the present case report, we describe morphological changes in a muscle biopsy obtained from a 62-year-old patient with gynecomastia and with the following neurological symptoms: dysphagia, dysarthria, wasting and fasciculation of the tongue, proximal weakness, fasciculations in the limb muscles, and an absence of all tendon reflexes. Neurogenic alternations were predominantly observed using light and electron microscopy. The angulated atrophic muscle fibers formed bundles. The numerous nuclei were pyknotic or pale, some of them were also ubiquitin positive; they were grouped inside so-called "nuclear sacks". At the ultrastructural level, atrophic muscle fibers revealed disruption and loss of sarcomeres, duplication of Z-line, and rod-like structures. The nuclei, often with irregular shapes, revealed varying degrees of chromatin condensation, from dispersed to highly condensed, like pyknotic nuclei. Occasionally electron-dense inclusions in the nuclei were found. Some myogenic features like hypertrophic muscle fibers and proliferation of connective tissue were also visible. The neurogenic and myogenic pathological changes suggested SBMA, which was confirmed with genetic analysis (trinucleotide CAG (glutamie)-repeat expansion in the androgen-receptor gene). PMID:25828775

  3. Unexpected morphological and karyological changes in invasive Carpobrotus (Aizoaceae) in Provence (S-E France) compared to native South African species.

    PubMed

    Verlaque, Régine; Affre, Laurence; Diadema, Katia; Suehs, Carey M; Médail, Frédéric

    2011-04-01

    Hybridization processes can lead to evolutionary changes, particularly in co-introduced congeneric plant species, such as Carpobrotus spp. which are recognized as invasive in Mediterranean climate regions. Morphological and karyological comparisons have therefore been made between native Carpobrotus edulis and C. acinaciformis in South Africa and their invasive counterparts in Provence (C. edulis and C. aff. acinaciformis). Morphological data exhibited the most significant differences in invasive C. aff. acinaciformis that forms a new phenotypic variant. Unexpected chromosomal restructuring has been highlighted for both taxa in Provence, with in particular a clear decrease in asymmetry, an increase in the intraspecific variability, and an interspecific convergence of karyotypes. These changes suggest a drift that has facilitated various crosses, and has been amplified through hybridization/introgression. Furthermore, several morphological and karyological transgressive characters have been found in the two invasive taxa. These results stress the important role and the rapidity of karyological changes in invasive processes. PMID:21513901

  4. Using boat-based mobile terrestrial laser scanning (TLS) in quantifying the flood-related changes in river channel morphology

    NASA Astrophysics Data System (ADS)

    Kasvi, E.; Alho, P.; Kukko, A.; Hyyppä, J.; Hyyppä, H.; Kaartinen, H.; Vaaja, M.

    2010-03-01

    Flooding has a major effect on their surrounding environment over time. Understanding the river system dynamics is important both in scientific manner and for societal purposes. Being able to map and quantify the flood-related erosion processes in a channel is essential for general understanding of the river dynamics as well as for improving flood protection and management. The variations in river bed material and the varying three dimensional flow conditions lead to asymmetries in the formation of the meanders and other channel formations and make the studying of the natural river channel dynamics challenging. To date, the detailed morphology of the fluvial landforms has been a challenge to measure. Field measurements for digital terrain model (DTM) creation based on traditional approaches are limited in riverine environment as steep river banks, curved point bars and dense vegetation create shadows on the sight of survey. Furthermore, these survey campaigns are usually rather time-consuming and might even be dangerous. Spatial or temporal coverage is rather diminished in these field measurements and consequently resolution of DTM is rather coarse. Therefore, new approaches for more detailed mapping of the flood-related geomorphologic changes in rivers are necessary in order to develop flood protection. In this study the boat-based, mobile mapping system (BoMMS) combined with a laser scanner was used to gather detailed, multi-temporal, pre- and post-flood topographical data in order to map the flood related geomorphic changes. The BoMMS- measurements were completed with static terrestrial LiDAR (Light Detection And Range) and mobile terrestrial LiDAR. The change detection was realized by subtracting the LiDAR-based DTMs. BoMMS-approach proved to be an effective and accurate way of mapping the river channel with only a small time-lag directly after flood. In addition, multi-temporal data set allowed a precise location and quantification of the flood-related erosion

  5. Morphological changes at Colima volcano caused the 2015 Hurricane Patricia investigated by repeated drone surveys and time lapse cameras

    NASA Astrophysics Data System (ADS)

    Walter, Thomas R.; Navarro, Carlos; Arambula, Raul; Salzer, Jackie; Reyes, Gabriel

    2016-04-01

    Colima is one of the most active volcanoes in Latin America, with frequent dome building eruptions and pyroclastic flow hazards. In July 2015 Colima had a new climax of eruptive activity, profoundly changing the summit morphology and redistributing volcanic ashes to the lower volcano apron. These unconsolidated ashes are prone to be mobilized by rainfall events, and therefore required close monitoring. A major hurricane then had landfall in western Mexico in October 2015, accumulating c. 450 mm of rainfall at a meteorological station at Nevado de Colima (3461 m) and immense lahar and ash deposit mobilization from Colima Volcano. Hurricane Patricia was the largest ever recorded category 5 storm, directly crossing the state of Colima. Due to the successful scientific advice and civil protection no human losses were directly associated to this lahar hazards. We have conducted drone overflight in profound valleys that directed the pyroclastic flows and lahars two days before and three days after the hurricane. Over 8,000 close range aerial photographs could be recorded, along with GPS locations of ground stations. Images were processed using the structure from motion methodology, and digital elevation models compared. Erosion locally exceeded 10 m vertically and caused significant landscape change. Mass mobilization unloaded the young pyroclastic deposits and led to significant underground heat loss and water boiling in the affected areas. We also firstly report the use of camera array set-ups along the same valley to monitor lahar deposition and erosion from different perspectives. Combining these photos using photogrammetric techniques allow time series of digital elevation change studies at the deepening erosional ravines, with large potential for future geomorphic monitoring. This study shows that photo monitoring is very useful for studying the link of volcano landscape evolution and hydrometerological extremes and for rapid assessment of indirect volcanic hazards.

  6. Severe methylenetetrahydrofolate reductase deficiency in mice results in behavioral anomalies with morphological and biochemical changes in hippocampus.

    PubMed

    Jadavji, Nafisa M; Deng, Liyuan; Leclerc, Daniel; Malysheva, Olga; Bedell, Barry J; Caudill, Marie A; Rozen, Rima

    2012-06-01

    The brain is particularly sensitive to folate metabolic disturbances, since methyl groups are critical for its functions. Methylenetetrahydrofolate reductase (MTHFR) generates the primary circulatory form of folate required for homocysteine remethylation to methionine. Neurological disturbances have been described in homocystinuria caused by severe MTHFR deficiency. The goal of this study was to determine if behavioral anomalies are present in severe Mthfr-deficient (Mthfr(-/-)) mice and to identify neurobiological changes that could contribute to these anomalies. Adult male mice of 3 Mthfr genotypes (+/+, +/-, -/-) were tested on motor, anxiety, exploratory and cognitive tasks. Volumes (whole brain and hippocampus) and morphology, global DNA methylation, apoptosis, expression of choline acetyltransferase (ChAT) and glucocorticoid receptor (GR), and concentrations of choline metabolites were assessed in hippocampus. Mthfr(-/-) mice had impairments in motor function and in short- and long-term memory, increased exploratory behavior and decreased anxiety. They showed decreased whole brain and hippocampal volumes, reduced thickness of the pyramidal cell layer of CA1 and CA3, and increased apoptosis in hippocampus. There was a disturbance in choline metabolism as manifested by differences in acetylcholine, betaine or glycerophosphocholine concentrations, and by increased ChAT levels. Mthfr(-/-) mice also had increased GR mRNA and protein. Our study has revealed significant anomalies in affective behavior and impairments in memory of Mthfr(-/-) mice. We identified structural changes, increased apoptosis, altered choline metabolism and GR dysregulation in hippocampus. These findings, as well as some similar observations in cerebellum, could contribute to the behavioral changes and suggest that choline is a critical metabolite in homocystinuria. PMID:22521626

  7. Anti-herbivore Structures of Paulownia tomentosa: Morphology, Distribution, Chemical Constituents and Changes During Shoot and Leaf Development

    PubMed Central

    Kobayashi, Sawa; Asai, Teigo; Fujimoto, Yoshinori; Kohshima, Shiro

    2008-01-01

    Background and Aims Recent studies have shown that small structures on plant surfaces serve ecological functions such as resistance against herbivores. The morphology, distribution, chemical composition and changes during shoot and leaf development of such small structures were examined on Paulownia tomentosa. Methods The morphology and distribution of the structures were studied under light microscopy, and their chemical composition was analysed using thin-layer chromatography and high-performance liquid chromatography. To further investigate the function of these structures, several simple field experiments and observations were also conducted. Key Results Three types of small structures on P. tomentosa were investigated: bowl-shaped organs, glandular hairs and dendritic trichomes. The bowl-shaped organs were densely aggregated on the leaves near flower buds and were determined to be extrafloral nectarines (EFNs) that secrete sugar and attract ants. Nectar production of these organs was increased by artificial damage to the leaves, suggesting an anti-herbivore function through symbiosis with ants. Glandular hairs were found on the surfaces of young and/or reproductive organs. Glandular hairs on leaves, stems and flowers secreted mucilage containing glycerides and trapped small insects. Secretions from glandular hairs on flowers and immature fruits contained flavonoids, which may provide protection against some herbivores. Yellow dendritic trichomes on the adaxial side of leaves also contained flavonoids identical to those secreted by the glandular hairs on fruits and flowers. Three special types of leaves, which differed from the standard leaves in shape, size and identity of small structures, developed near young shoot tips or young flower buds. The density of small structures on these leaf types was higher than on standard leaves, suggesting that these leaf types may be specialized to protect young leaves or reproductive organs. Changes in the small structures

  8. Ultrastructural study on the morphological changes in indigenous bacteria of mucous layer and chyme throughout the rat intestine

    PubMed Central

    MANTANI, Youhei; ITO, Eri; NISHIDA, Miho; YUASA, Hideto; MASUDA, Natsumi; QI, Wang-Mei; KAWANO, Junichi; YOKOYAMA, Toshifumi; HOSHI, Nobuhiko; KITAGAWA, Hiroshi

    2015-01-01

    Indigenous bacteria in the alimentary tract are exposed to various bactericidal peptides and digestive enzymes, but the viability status and morphological changes of indigenous bacteria are unclear. Therefore, the present study aimed to ultrastructurally clarify the degeneration and viability status of indigenous bacteria in the rat intestine. The majority of indigenous bacteria in the ileal mucous layer possessed intact cytoplasm, but the cytoplasm of a few bacteria contained vacuoles. The vacuoles were more frequently found in bacteria of ileal chyme than in those of ileal mucous layer and were found in a large majority of bacteria in both the mucous layer and chyme throughout the large intestine. In the dividing bacteria of the mucous layer and chyme throughout the intestine, the ratio of area occupied by vacuoles was almost always less than 10%. Lysis or detachment of the cell wall in the indigenous bacteria was more frequently found in the large intestine than in the ileum, whereas bacterial remnants, such as cell walls, were distributed almost evenly throughout the intestine. In an experimental control of long-time-cultured Staphylococcus epidermidis on agar, similar vacuoles were also found, but cell-wall degeneration was never observed. From these findings, indigenous bacteria in the mucous layer were ultrastructurally confirmed to be the source of indigenous bacteria in the chyme. Furthermore, the results suggested that indigenous bacteria were more severely degenerated toward the large intestine and were probably degraded in the intestine. PMID:25890991

  9. Surface morphology changes and deuterium retention in Toughened, Fine-grained Recrystallized Tungsten under high-flux irradiation conditions

    NASA Astrophysics Data System (ADS)

    Oya, M.; Lee, H. T.; Ueda, Y.; Kurishita, H.; Oyaidzu, M.; Hayashi, T.; Yoshida, N.; Morgan, T. W.; De Temmerman, G.

    2015-08-01

    Surface morphology changes and deuterium (D) retention in Toughened, Fine-Grained Recrystallized Tungsten (TFGR W) with TaC dispersoids (W-TaC) and pure tungsten exposed to D plasmas to a fluence of 1026 D/m2 s were studied as a function of the D ion flux (1022-1024 D/m2 s). As the flux increased from 1022 D/m2 s to 1024 D/m2 s, the numbers of blisters increased for both materials. However, smaller blisters were observed on W-TaC compared to pure W. In W-TaC, cracks beneath the surface along grain boundaries were observed, which were comparable to the blister sizes. The reason for the smaller blister sizes may arise from smaller grain sizes of W-TaC. In addition, reduction of the D retention in W-TaC was observed for higher flux exposures. D depth profiles indicate this reduction arises due to decrease in trapping in the bulk.

  10. Immunoexpression of intermediate filaments and morphological changes in the liver and bile duct of rats infected with Fasciola hepatica.

    PubMed

    Kolodziejczyk, L; Laszczyńska, M; Masiuk, M; Grabowska, M; Skrzydlewska, E

    2015-01-01

    We investigated the immunoexpression of the intermediate filament proteins, cytokeratin and desmin, and the morphological changes in the liver of rats during experimental fasciolosis at 4, 7 and 10 weeks post-infection. Rats were infected with 30 Fasciola hepatica metacercariae. Paraffin sections of the liver were stained using H & E, PAS and azan stains. Immunohistochemical reactions were performed using antibodies against cytokeratin and desmin. The experimental F. hepatica infection led to fibrosis and cirrhosis of the liver, and to inflammation of the common bile ducts. The expression of cytokeratin was increased in the epithelial cells of both the liver bile ductules at 4, 7 and 10 weeks post-infection and in the common bile ducts at 7 and 10 weeks post-infection compared to uninfected rats; expression in the common bile ducts was more intense. The myofibroblasts of the liver and smooth myocytes of the interlobular bile ducts and common bile ducts, showed a slight increase in desmin expression compared to the uninfected rats. The increased expression of cytokeratins in the hyperplastic rat common bile duct epithelium during the biliary phase of fasciolosis at 7 and 10 weeks post-infection may be explained by mechanical irritation by the parasite and an inflammatory reaction in the bile duct epithelium and in periductal fibrous tissue. PMID:25923046

  11. Predicting morphological changes DS New Naga-Hammadi Barrage for extreme Nile flood flows: A Monte Carlo analysis

    PubMed Central

    Sattar, Ahmed M.A.; Raslan, Yasser M.

    2013-01-01

    While construction of the Aswan High Dam (AHD) has stopped concurrent flooding events, River Nile is still subject to low intensity flood waves resulting from controlled release of water from the dam reservoir. Analysis of flow released from New Naga-Hammadi Barrage, which is located at 3460 km downstream AHD indicated an increase in magnitude of flood released from the barrage in the past 10 years. A 2D numerical mobile bed model is utilized to investigate the possible morphological changes in the downstream of Naga-Hammadi Barrage from possible higher flood releases. Monte Carlo simulation analyses (MCS) is applied to the deterministic results of the 2D model to account for and assess the uncertainty of sediment parameters and formulations in addition to sacristy of field measurements. Results showed that the predicted volume of erosion yielded the highest uncertainty and variation from deterministic run, while navigation velocity yielded the least uncertainty. Furthermore, the error budget method is used to rank various sediment parameters for their contribution in the total prediction uncertainty. It is found that the suspended sediment contributed to output uncertainty more than other sediment parameters followed by bed load with 10% less order of magnitude. PMID:25685476

  12. The Effect of Cochinchina momordica Seed Extract on Gastric Acid Secretion and Morphologic Change in Aged Rat Stomach

    PubMed Central

    Jo, Hyun Jin; Nam, Ryoung Hee; Chang, Hyun; Kim, Joo-Hyon; Park, Ji Hyun; Kang, Jung Mook; Lee, Dong Ho; Jung, Hyun Chae

    2013-01-01

    Background/Aims Cochinchina momordica seed extract (SK-MS10) has a gastric protective effect. We aimed to assess the effect of SK-MS10 on gastric acid secretion with morphologic changes in the aged rat. Methods Acid secretions were evaluated in the male F344 rats of four different ages (6-, 31-, 74-week, and 2-year). The 31-week-old rats were divided to three groups and continuously administered chow containing vehicle, SK-MS10 and lansoprazole, respectively. At the age of 74 weeks and 2 years, basal and stimulated acid was measured and the expression of mRNA and protein of H+-K+-ATPase were determined. The area of connective tissue of lamina propria was measured. Results Basal and stimulated gastric acid significantly decreased and connective tissue of lamina propria increased with age. The expression of mRNA and protein of H+-K+-ATPase significantly decreased with age. However, 74-week-old rats in the SK-MS10 group had higher stimulated gastric acid secretion than those in the vehicle and lansoprazole groups. In 2-year-old rats of SK-MS10 group, there was no increase of connective tissue. Conclusions As SK-MS10 kept the capacity of acid secretion as well as connective tissue area to comparable to young rats, it might valuable to perform further research regarding mechanism of SK-MS10 as an antiaging agent in the stomach. PMID:24073314

  13. Changes in the permeability and morphology of dentine surfaces after brushing with a Thai herbal toothpaste: A preliminary study

    PubMed Central

    Vajrabhaya, La-ongthong; Korsuwannawong, Suwanna; Harnirattisai, Choltacha; Teinchai, Chayada

    2016-01-01

    Objectives: The aim of this study was to evaluate dentine permeability after brushing with Twin Lotus®, Thai herbal toothpaste by comparing with Sensodyne Rapid Relief®, a commercial desensitizing toothpaste, and also after artificial saliva (AS) immersion or citric acid challenge. Materials and Methods: Dentine discs from human mandibular third molars were divided into three groups (n = 20) and brushed with either experimental toothpaste or water (control) for 2 min with an automated toothbrush. Then, 10 discs were immersed in AS, and the other 10 discs were immersed in 6% citric acid to simulate the conditions of the oral environment. The dentine permeability of each specimen was measured before brushing and after each treatment using a fluid filtration system. Morphological changes in the dentine were observed using scanning electron microscopy (SEM). Results: Both toothpastes significantly reduced dentine permeability, and a crystalline precipitate was observed on the dentine surface under SEM observation. No significant difference was found between the two toothpaste groups with regard to dentine permeability after brushing and AS or acid immersion. Conclusions: The dentine permeability reduction caused by the two toothpastes did not differ after brushing or after AS or citric acid immersion. PMID:27095904

  14. Assessment of Morphological and Functional Changes in Organs of Rats after Intramuscular Introduction of Iron Nanoparticles and Their Agglomerates

    PubMed Central

    Sizova, Elena; Miroshnikov, Sergey; Yausheva, Elena; Polyakova, Valentina

    2015-01-01

    The research was performed on male Wistar rats based on assumptions that new microelement preparations containing metal nanoparticles and their agglomerates had potential. Morphological and functional changes in tissues in the injection site and dynamics of chemical element metabolism (25 indicators) in body were assessed after repeated intramuscular injections (total, 7) with preparation containing agglomerate of iron nanoparticles. As a result, iron depot was formed in myosymplasts of injection sites. The quantity of muscle fibers having positive Perls' stain increased with increasing number of injections. However, the concentration of the most chemical elements and iron significantly decreased in the whole skeletal muscle system (injection sites are not included). Consequently, it increased up to the control level after the sixth and the seventh injections. Among the studied organs (liver, kidneys, and spleen), Caspase-3 expression was revealed only in spleen. The expression had a direct dependence on the number of injections. Processes of iron elimination from preparation containing nanoparticles and their agglomerates had different intensity. PMID:25789310

  15. Joint use of multiple Synthetic Aperture Radar imagery for the detection of bivalve beds and morphological changes on intertidal flats

    NASA Astrophysics Data System (ADS)

    Gade, Martin; Melchionna, Sabrina

    2016-03-01

    We analyzed a large amount of high-resolution Synthetic Aperture Radar (SAR) data of dry-fallen intertidal flats on the German North Sea coast with respect to the imaging of sediments, macrophytes, and mussels. TerraSAR-X and Radarsat-2 images of four test areas acquired from 2008 to 2013 form the basis for the present investigation and are used to demonstrate that pairs of SAR images, if combined through basic algebraic operations, can already provide indicators for morphological changes and for bivalve (oyster and mussel) beds. Multi-temporal analyses of series of SAR images allow detecting bivalve beds, since the radar backscattering from those beds is generally high, whereas that from sediments may vary with imaging geometry and environmental conditions. Our results further show evidence that also single-acquisition, dual-polarization SAR imagery can be used in this respect. The polarization coefficient (i.e., the ratio of the difference and the sum of both co-polarizations) can be used to infer indicators for oyster and blue-mussel beds.