Transfer from blue light or green light to white light partially reverses changes in ocular refraction and anatomy of developing guinea pigs.

PubMed

Qian, Yi-Feng; Liu, Rui; Dai, Jin-Hui; Chen, Min-Jie; Zhou, Xing-Tao; Chu, Ren-Yuan

2013-09-26

Relative to the broadband white light (BL), postnatal guinea pigs develop myopia in a monochromic middle-wavelength light (ML, 530 nm) environment and develop hyperopia in a monochromic short-wavelength light (SL, 430 nm) environment. We investigated whether transfer from SL or ML to BL leads to recuperation of ocular refraction and anatomy of developing guinea pigs. Two-week-old guinea pigs were given (a) SL for 20 weeks, (b) SL recuperation (SLR, SL for 10 weeks then BL for 10 weeks), (c) ML for 20 weeks, (d) ML recuperation (MLR, ML for 10 weeks then BL for 10 weeks), or (e) BL for 20 weeks. Two weeks after transfer from ML to BL (MLR group), ocular refraction increased from 1.95 ± 0.35 D to 2.58 ± 0.24 D, and vitreous length decreased from 3.48 ± 0.06 mm to 3.41 ± 0.06 mm. Two weeks after transfer from SL to BL (SLR group), ocular refraction decreased from 5.65 ± 0.61 D to 4.33 ± 0.49 D, and vitreous length increased from 3.18 ± 0.07 mm to 3.26 ± 0.11 mm. The MLR and SLR groups had final ocular refractions that were significantly different from those of the ML and SL groups at 20 weeks (ML vs. MLR: p < 0.0001; SL vs. SLR: p < 0.0001) but were still significantly different from the BL group (BL vs. MLR: p = 0.0120; BL vs. SLR: p = 0.0010). These results suggest that recuperation was not complete after return to BL for 10 weeks.

He-Ion Microscopy as a High-Resolution Probe for Complex Quantum Heterostructures in Core-Shell Nanowires.

PubMed

Pöpsel, Christian; Becker, Jonathan; Jeon, Nari; Döblinger, Markus; Stettner, Thomas; Gottschalk, Yeanitza Trujillo; Loitsch, Bernhard; Matich, Sonja; Altzschner, Marcus; Holleitner, Alexander W; Finley, Jonathan J; Lauhon, Lincoln J; Koblmüller, Gregor

2018-06-13

Core-shell semiconductor nanowires (NW) with internal quantum heterostructures are amongst the most complex nanostructured materials to be explored for assessing the ultimate capabilities of diverse ultrahigh-resolution imaging techniques. To probe the structure and composition of these materials in their native environment with minimal damage and sample preparation calls for high-resolution electron or ion microscopy methods, which have not yet been tested on such classes of ultrasmall quantum nanostructures. Here, we demonstrate that scanning helium ion microscopy (SHeIM) provides a powerful and straightforward method to map quantum heterostructures embedded in complex III-V semiconductor NWs with unique material contrast at ∼1 nm resolution. By probing the cross sections of GaAs-Al(Ga)As core-shell NWs with coaxial GaAs quantum wells as well as short-period GaAs/AlAs superlattice (SL) structures in the shell, the Al-rich and Ga-rich layers are accurately discriminated by their image contrast in excellent agreement with correlated, yet destructive, scanning transmission electron microscopy and atom probe tomography analysis. Most interestingly, quantitative He-ion dose-dependent SHeIM analysis of the ternary AlGaAs shell layers and of compositionally nonuniform GaAs/AlAs SLs reveals distinct alloy composition fluctuations in the form of Al-rich clusters with size distributions between ∼1-10 nm. In the GaAs/AlAs SLs the alloy clustering vanishes with increasing SL-period (>5 nm-GaAs/4 nm-AlAs), providing insights into critical size dimensions for atomic intermixing effects in short-period SLs within a NW geometry. The straightforward SHeIM technique therefore provides unique benefits in imaging the tiniest nanoscale features in topography, structure and composition of a multitude of diverse complex semiconductor nanostructures.

Interactions between similar and dissimilar charged interfaces in the presence of multivalent anions.

PubMed

Moazzami-Gudarzi, Mohsen; Adam, Pavel; Smith, Alexander M; Trefalt, Gregor; Szilágyi, István; Maroni, Plinio; Borkovec, Michal

2018-04-04

Direct force measurements involving amidine latex (AL) and sulfate latex (SL) particles in aqueous solutions containing multivalent ferrocyanide anions are presented. These measurements feature three different pairs of particles, namely SL-SL, AL-SL, and AL-AL. The force profiles are quantitatively interpreted in terms of the theory by Derjaguin, Landau, Verwey, and Overbeek (DLVO) that is combined with a short-ranged exponential attraction. In monovalent salt solutions, the AL particles are positively charged, while the SL particles are negatively charged. In solutions containing ferrocyanide, the charge of the AL particles is reversed as the concentration is increased. The longer-ranged component of all force profiles is fully compatible with DLVO theory, provided effects of charge regulation are included. At shorter distances, an additional exponential attraction must be introduced, whereby the respective decay length is about 2 nm for the AL-AL pair, and below 1 nm for the SL-SL pair. This non-DLVO force is intermediate for the asymmetric AL-SL pair. These additional forces are probably related to charge fluctuations, patch-charged interactions, or hydrophobic forces.

ALIAS (Acquisition and Logistics Information and Analysis System) Maintenance and Expansion Guide. Volume 2.

DTIC Science & Technology

1984-10-31

PURPOSE UTILITIES! C. C.CT2 .t tt.t t.t, 4.t44.• 4 *• tt 4t t • t t tt* t tttt t SCONTROL check-2 SUBRO.UTINE ccat2 .sl,lenl,s2,len2,sr, lenr ,nlenr) C.4...same address as sI or s2 C-C t lenr length of sr Cin 4lenr naxiPsum length allowable for sr C.tETH0Q. C D.TS. refers to a Delimited Text String, in which...DECLARATIONS **. !9TESER !enIlen2,1!n3,!en4, lenr ,m1enr CKARACTER.25S sl, sZ, s3, s4., sr C.* ABSTRACT *.. Cl.PURPOSE -erfor..s sr sl ’’ s2 ’: s3 C.OUOIT HIS.TORY

Stable Tearing and Buckling Responses of Unstiffened Aluminum Shells with Long Cracks

NASA Technical Reports Server (NTRS)

Starnes, James H., Jr.; Rose, Cheryl A.

1999-01-01

The results of an analytical and experimental study of the nonlinear response of thin, unstiffened, aluminum cylindrical shells with a long longitudinal crack are presented. The shells are analyzed with a nonlinear shell analysis code that accurately accounts for global and local structural response phenomena. Results are presented for internal pressure and for axial compression loads. The effect of initial crack length on the initiation of stable crack growth and unstable crack growth in typical shells subjected to internal pressure loads is predicted using geometrically nonlinear elastic-plastic finite element analyses and the crack-tip-opening angle (CTOA) fracture criterion. The results of these analyses and of the experiments indicate that the pressure required to initiate stable crack growth and unstable crack growth in a shell subjected to internal pressure loads decreases as the initial crack length increases. The effects of crack length on the prebuckling, buckling and postbuckling responses of typical shells subjected to axial compression loads are also described. For this loading condition, the crack length was not allowed to increase as the load was increased. The results of the analyses and of the experiments indicate that the initial buckling load and collapse load for a shell subjected to axial compression loads decrease as the initial crack length increases. Initial buckling causes general instability or collapse of a shell for shorter initial crack lengths. Initial buckling is a stable local response mode for longer initial crack lengths. This stable local buckling response is followed by a stable postbuckling response, which is followed by general or overall instability of the shell.

Stable Tearing and Buckling Responses of Unstiffened Aluminum Shells with Long Cracks

NASA Technical Reports Server (NTRS)

Starnes, James H., Jr.; Rose, Cheryl A.

1998-01-01

The results of an analytical and experimental study of the nonlinear response of thin, unstiffened, aluminum cylindrical shells with a long longitudinal crack are presented. The shells are analyzed with a nonlinear shell analysis code that accurately accounts for global and local structural response phenomena. Results are presented for internal pressure and for axial compression loads. The effect of initial crack length on the initiation of stable crack growth and unstable crack growth in typical shells subjected to internal pressure loads is predicted using geometrically nonlinear elastic-plastic finite element analyses and the crack-tip-opening angle (CTOA) fracture criterion. The results of these analyses and of the experiments indicate that the pressure required to initiate stable crack growth and unstable crack growth in a shell subjected to internal pressure loads decreases as the initial crack length increases. The effects of crack length on the prebuckling, buckling and postbuckling responses of typical shells subjected to axial compression loads are also described. For this loading condition, the crack length was not allowed to increase as the load was increased. The results of the analyses and of the experiments indicate that the initial buckling load and collapse load for a shell subjected to axial compression loads decrease as the initial crack length increases. Initial buckling causes general instability or collapse of a shell for shorter initial crack lengths. Initial buckling is a stable local response mode for longer initial crack lengths. This stable local buckling response is followed by a stable postbuckling response, which is followed by general or overall instability of the shell.

Transcriptional regulation of SlPYL, SlPP2C, and SlSnRK2 gene families encoding ABA signal core components during tomato fruit development and drought stress.

PubMed

Sun, Liang; Wang, Yan-Ping; Chen, Pei; Ren, Jie; Ji, Kai; Li, Qian; Li, Ping; Dai, Sheng-Jie; Leng, Ping

2011-11-01

In order to characterize the potential transcriptional regulation of core components of abscisic acid (ABA) signal transduction in tomato fruit development and drought stress, eight SlPYL (ABA receptor), seven SlPP2C (type 2C protein phosphatase), and eight SlSnRK2 (subfamily 2 of SNF1-related kinases) full-length cDNA sequences were isolated from the tomato nucleotide database of NCBI GenBank. All SlPYL, SlPP2C, and SlSnRK2 genes obtained are homologous to Arabidopsis AtPYL, AtPP2C, and AtSnRK2 genes, respectively. Based on phylogenetic analysis, SlPYLs and SlSnRK2s were clustered into three subfamilies/subclasses, and all SlPP2Cs belonged to PP2C group A. Within the SlPYL gene family, SlPYL1, SlPYL2, SlPYL3, and SlPYL6 were the major genes involved in the regulation of fruit development. Among them, SlPYL1 and SlPYL2 were expressed at high levels throughout the process of fruit development and ripening; SlPYL3 was strongly expressed at the immature green (IM) and mature green (MG) stages, while SlPYL6 was expressed strongly at the IM and red ripe (RR) stages. Within the SlPP2C gene family, the expression of SlPP2C, SlPP2C3, and SlPP2C4 increased after the MG stage; SlPP2C1 and SlPP2C5 peaked at the B3 stage, while SlPP2C2 and SlPP2C6 changed little during fruit development. Within the SlSnRK2 gene family, the expression of SlSnRK2.2, SlSnRK2.3, SlSnRK2.4, and SlSnRK2C was higher than that of other members during fruit development. Additionally, most SlPYL genes were down-regulated, while most SlPP2C and SlSnRK2 genes were up-regulated by dehydration in tomato leaf.

Thin filament length in the cardiac sarcomere varies with sarcomere length but is independent of titin and nebulin.

PubMed

Kolb, Justin; Li, Frank; Methawasin, Mei; Adler, Maya; Escobar, Yael-Natalie; Nedrud, Joshua; Pappas, Christopher T; Harris, Samantha P; Granzier, Henk

2016-08-01

Thin filament length (TFL) is an important determinant of the force-sarcomere length (SL) relation of cardiac muscle. However, the various mechanisms that control TFL are not well understood. Here we tested the previously proposed hypothesis that the actin-binding protein nebulin contributes to TFL regulation in the heart by using a cardiac-specific nebulin cKO mouse model (αMHC Cre Neb cKO). Atrial myocytes were studied because nebulin expression has been reported to be most prominent in this cell type. TFL was measured in right and left atrial myocytes using deconvolution optical microscopy and staining for filamentous actin with phalloidin and for the thin filament pointed-end with an antibody to the capping protein Tropomodulin-1 (Tmod1). Results showed that TFLs in Neb cKO and littermate control mice were not different. Thus, deletion of nebulin in the heart does not alter TFL. However, TFL was found to be ~0.05μm longer in the right than in the left atrium and Tmod1 expression was increased in the right atrium. We also tested the hypothesis that the length of titin's spring region is a factor controlling TFL by studying the Rbm20(ΔRRM) mouse which expresses titins that are ~500kDa (heterozygous mice) and ~1000kDa (homozygous mice) longer than in control mice. Results revealed that TFL was not different in Rbm20(ΔRRM) mice. An unexpected finding in all genotypes studied was that TFL increased as sarcomeres were stretched (~0.1μm per 0.35μm of SL increase). This apparent increase in TFL reached a maximum at a SL of ~3.0μm where TFL was ~1.05μm. The SL dependence of TFL was independent of chemical fixation or the presence of cardiac myosin-binding protein C (cMyBP-C). In summary, we found that in cardiac myocytes TFL varies with SL in a manner that is independent of the size of titin or the presence of nebulin. Copyright © 2016. Published by Elsevier Ltd.

Biometric studies on the bivalves Astarte elliptica, A. borealis and A. montagui in Kiel Bay (Western Baltic Sea)

NASA Astrophysics Data System (ADS)

Schaefer, R.; Trutschler, K.; Rumohr, H.

1985-09-01

The three Astarte species were studied in June 1983 at two sites in Kiel Bay, “Süderfahrt” and “Schleimünde”, at 20 m depth. Shell length to live wet weight correlations are given for all three species; for A. elliptica also shell-free dry weight, shell dry weight, ash-free dry weight of the soft body and ash-free dry weight of the shell are recorded as functions of the shell length. In the logarithmic length/weight regression analysis the coefficients of slope for A. elliptica and A. borealis are 3. For A. montagui, that coefficient is significantly greater than 3. Weight conversion factors, calculated for A. elliptica, revealed a mean weight composition of 31.5 % water in the mantle cavity and tissue water, 64.5 % shell ash, 2.1 % organic content of shell, 1.7 % organic content of the soft body and 0.4 % ash of the soft body. An isometric growth of shell length and shell breadth is confirmed for A. borealis, while A. montagui exhibits positive allometric shell growth and changes its shape during life.

Spliced leader RNA trans-splicing discovered in copepods

NASA Astrophysics Data System (ADS)

Yang, Feifei; Xu, Donghui; Zhuang, Yunyun; Yi, Xiaoyan; Huang, Yousong; Chen, Hongju; Lin, Senjie; Campbell, David A.; Sturm, Nancy R.; Liu, Guangxing; Zhang, Huan

2015-12-01

Copepods are one of the most abundant metazoans in the marine ecosystem, constituting a critical link in aquatic food webs and contributing significantly to the global carbon budget, yet molecular mechanisms of their gene expression are not well understood. Here we report the detection of spliced leader (SL) trans-splicing in calanoid copepods. We have examined nine species of wild-caught copepods from Jiaozhou Bay, China that represent the major families of the calanoids. All these species contained a common 46-nt SL (CopepodSL). We further determined the size of CopepodSL precursor RNA (slRNA; 108-158 nt) through genomic analysis and 3‧-RACE technique, which was confirmed by RNA blot analysis. Structure modeling showed that the copepod slRNA folded into typical slRNA secondary structures. Using a CopepodSL-based primer set, we selectively enriched and sequenced copepod full-length cDNAs, which led to the characterization of copepod transcripts and the cataloging of the complete set of 79 eukaryotic cytoplasmic ribosomal proteins (cRPs) for a single copepod species. We uncovered the SL trans-splicing in copepod natural populations, and demonstrated that CopepodSL was a sensitive and specific tool for copepod transcriptomic studies at both the individual and population levels and that it would be useful for metatranscriptomic analysis of copepods.

Remediation of muddy tidal flat sediments using hot air-dried crushed oyster shells.

PubMed

Yamamoto, Tamiji; Kondo, Shunsuke; Kim, Kyung-Hoi; Asaoka, Satoshi; Yamamoto, Hironori; Tokuoka, Makoto; Hibino, Tadashi

2012-11-01

In order to prove that hot air-dried crushed oyster shells (HACOS) are effective in reducing hydrogen sulfide in muddy tidal flat sediments and increasing the biomass, field experiments were carried out. The concentration of hydrogen sulfide in the interstitial water, which was 16 mg SL(-1) before the application of HACOS, decreased sharply and maintained almost zero in the experimental sites (HACOS application sites) for one year, whereas it was remained at ca. 5 mg SL(-1) in the control sites. The number of macrobenthos individuals increased to 2-4.5 times higher than that in the control site. Using a simple numerical model, the effective periods for suppression of hydrogen sulfide were estimated to be 3.2-7.6 and 6.4-15.2 years for the experimental sites with 4 and 8 tons per 10 × 10 × 0.2m area, respectively. From these results, it is concluded that HACOS is an effective material to remediate muddy tidal flats. Copyright © 2012 Elsevier Ltd. All rights reserved.

Myosin head orientation: a structural determinant for the Frank-Starling relationship

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

Farman, Gerrie P.; Gore, David; Allen, Edward

The cellular mechanism underlying the Frank-Starling law of the heart is myofilament length-dependent activation. The mechanism(s) whereby sarcomeres detect changes in length and translate this into increased sensitivity to activating calcium has been elusive. Small-angle X-ray diffraction studies have revealed that the intact myofilament lattice undergoes numerous structural changes upon an increase in sarcomere length (SL): lattice spacing and the I{sub 1,1}/I{sub 1,0} intensity ratio decreases, whereas the M3 meridional reflection intensity (I{sub M3}) increases, concomitant with increases in diastolic and systolic force. Using a short ({approx}10 ms) X-ray exposure just before electrical stimulation, we were able to obtain detailedmore » structural information regarding the effects of external osmotic compression (with mannitol) and obtain SL on thin intact electrically stimulated isolated rat right ventricular trabeculae. We show that over the same incremental increases in SL, the relative changes in systolic force track more closely to the relative changes in myosin head orientation (as reported by IM3) than to the relative changes in lattice spacing. We conclude that myosin head orientation before activation determines myocardial sarcomere activation levels and that this may be the dominant mechanism for length-dependent activation.« less

Schistura megalodon species nova, a new river loach from the Irra-waddy basin in Dehong, Yunnan, China (Teleostei: Cypriniformes: Nemacheilidae).

PubMed

Endruweit, Marco

2014-09-01

A new species of river loach, Schistura megalodon sp. nov., is described from the Irrawaddy basin in Yingjiang County, Dehong Autonomous Prefecture, Yunnan Province, China. The following combination of diagnostic characters serve to distinguish it from all other congeners in the given zoogeographical region: a large processus dentiformes in the upper jaw, a short pre-anus length of 65.4%-66.3% of SL, long paired fins (pectoral: 20.8%-24.2% of SL; pelvic: 17.9%-20.6% of SL), a wide body of 9.7%-11.3% of SL at anal fin origin, an incomplete lateral line, the absence of an orbital lobe, and a oad and distinct basicaudal bar with forward extensions.

Size dependence of the melting temperature of metallic nanoclusters from the viewpoint of the thermodynamic theory of similarity

NASA Astrophysics Data System (ADS)

Samsonov, V. M.; Vasilyev, S. A.; Bembel, A. G.

2016-08-01

The generalized Thomson formula T m = T m (∞) (1-δ) R for the melting point of small objects T m has been analyzed from the viewpoint of the thermodynamic theory of similarity, where R is the radius of the particle and T m (∞) is the melting point of the corresponding large crystal. According to this formula, the parameter δ corresponds to the value of the radius of the T m ( R -1) particle obtained by the linear extrapolation of the dependence to the melting point of the particle equal to 0 K. It has been shown that δ = αδ0, where α is the factor of the asphericity of the particle (shape factor). In turn, the redefined characteristic length δ0 is expressed through the interphase tension σ sl at the boundary of the crystal with its own melt, the specific volume of the solid phase v s and the macroscopic value of the heat of fusion λ∞:δ0 = 2σ sl v s /λ∞. If we go from the reduced radius of the particle R/δ to the redefined reduced radius R/ r 1 or R/ d, where r 1 is the radius of the first coordination shell and d ≈ r 1 is the effective atomic diameter, then the simplex δ/ r 1 or δ/ d will play the role of the characteristic criterion of thermodynamic similarity. At a given value of α, this role will be played by the simplex Estimates of the parameters δ0 and δ0/ d have been carried out for ten metals with different lattice types. It has been shown that the values of the characteristic length δ0 are close to 1 nm and that the simplex δ0/ d is close to unity. In turn, the calculated values of the parameter δ agree on the order of magnitude with existing experimental data.

Two new species of shovel-jaw carp Onychostoma (Teleostei: Cyprinidae) from southern Vietnam.

PubMed

Hoang, Huy Duc; Pham, Hung Manh; Tran, Ngan Trong

2015-05-22

Two new species of large shovel-jaw carps in the genus Onychostoma are described from the upper Krong No and middle Dong Nai drainages of the Langbiang Plateau in southern Vietnam. These new species are known from streams in montane mixed pine and evergreen forests between 140 and 1112 m. Their populations are isolated in the headwaters of the upper Sre Pok River of the Mekong basin and in the middle of the Dong Nai basin. Both species are differentiated from their congeners by a combination of the following characters: transverse mouth opening width greater than head width, 14-17 predorsal scales, caudal-peduncle length 3.9-4.2 times in SL, no barbels in adults and juveniles, a strong serrated last simple ray of the dorsal fin, and small eye diameter (20.3-21.5% HL). Onychostoma krongnoensis sp. nov. is differentiated from Onychostoma dongnaiensis sp. nov. by body depth (4.0 vs. 3.2 times in SL), predorsal scale number (14-17 vs. 14-15), dorsal-fin length (4.5 vs. 4.2 times in SL), caudal-peduncle length (3.9 vs. 4.2 times in SL), colour in life (dark vs. bright), and by mitochondrial DNA (0.2% sequence divergence). Molecular evidence indicates that both species are members of Onychostoma and are distinct from all congeners sampled (uncorrected sequence divergences at the 16S rRNA gene of >2.0% for all Onychostoma for which homologous 16S rRNA sequences are available).

Root resorption, treatment time and extraction rate during orthodontic treatment with self-ligating and conventional brackets

PubMed Central

2014-01-01

Introduction This study determined the amount and severity of EARR (external apical root resorption) after orthodontic treatment with self-ligating (SL) and conventional (Non-SL) brackets. Differences regarding rate of extraction cases, appointments and treatment time were evaluated. Material and methods 213 patients with a mean age of 12.4 ± 2.2 years were evaluated retrospectively. The treatments were performed with SL brackets (n = 139, Smartclip, 3 M Unitek, USA) or Non-SL brackets (n = 74, Victory Series, 3 M Unitek, USA). Measurements of the crown and root length of the incisors were taken using panoramic radiographs. Three-factor analysis of variance (ANOVA) was performed for an appliance effect. Results There was no difference between patients treated with Non-SL or SL brackets regarding the amount (in percentage) of EARR (Non-SL: 4.5 ± 6.6 vs. SL: 3.0 ± 5.6). Occurrence of severe EARR (sEARR) did also not differ between the two groups (Non-SL 0.5 vs. SL: 0.3). The percentage of patients with need of tooth extraction for treatment (Non SL: 8.1 vs. SL: 6.9) and the number of appointments (Non-SL: 12.4 ± 3.4 vs. SL: 13.9 ± 3.3) did not show any differences. The treatment time was shorter with Non-SL brackets (Non-SL: 18.1 ± 5.3 vs. SL: 20.7 ± 4.9 months). Conclusions This is the largest study showing that there is no difference in the amount of EARR, number of appointments and extraction rate between conventional and self-ligating brackets. For the first time we could demonstrate that occurrence of sEARR does not differ between the two types of brackets. PMID:24456620

Order-Order Transition of C → sdG → sL → S in ABC Triblock Copolymer Thin Film Induced by Solvent Vapor.

PubMed

Luo, Chunxia; Huang, Weihuan; Han, Yanchun

2009-04-01

The morphology transition of polystyrene-block-poly(butadiene)-block-poly(2-vinylpyridine) (SBV) triblock thin film induced in benzene vapor showing weak selectivity for PS is investigated. The order-order transitions (OOT) in the sequence of core-shell cylinders (C), sphere in 'diblock gyroid' (sdG), sphere in lamella (sL) and sphere (S) are observed. The projection along (111) direction in Gyroid phase (sdG(111)) is found to epitaxially grow from C(001) in the film. Instead of sdG(111), sdG(110)(0.1875) develops to the phase of sL. Consequently, the film experiences the transition sequence of sdG(111) → sdG(211) → sdG(110)(0.25)  → sdG(110)(0.1875) between C and sL. The mechanism is analyzed from the total surface area of the blocks. Copyright © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Manipulating the stride length/stride velocity relationship of walking using a treadmill and rhythmic auditory cueing in non-disabled older individuals. A short-term feasibility study.

PubMed

Eikema, D J A; Forrester, L W; Whitall, J

2014-09-01

One target for rehabilitating locomotor disorders in older adults is to increase mobility by improving walking velocity. Combining rhythmic auditory cueing (RAC) and treadmill training permits the study of the stride length/stride velocity ratio (SL/SV), often reduced in those with mobility deficits. We investigated the use of RAC to increase velocity by manipulating the SL/SV ratio in older adults. Nine participants (6 female; age: 61.1 ± 8.8 years) walked overground on a gait mat at preferred and fast speeds. After acclimatization to comfortable speed on a treadmill, participants adjusted their cadence to match the cue for 3 min at 115% of preferred speed by either (a) increasing stride length only or (b) increasing stride frequency only. Following training, participants walked across the gait mat at preferred velocity without, and then with, RAC. Group analysis determined no immediate overground velocity increase, but reintroducing RAC did produce an increase in velocity after both conditions. Group and single subject analysis determined that the SL/SV ratio changed in the intended direction only in the stride length condition. We conclude that RAC is a powerful organizer of gait parameters, evidenced by its induced after-effects following short duration training. Copyright © 2014 Elsevier B.V. All rights reserved.

Schistura megalodon species nova, a new river loach from the Irra-waddy basin in Dehong, Yunnan, China (Teleostei: Cypriniformes: Nemacheilidae)

PubMed Central

Endruweit, Marco

2014-01-01

A new species of river loach, Schistura megalodon sp. nov., is described from the Irrawaddy basin in Yingjiang County, Dehong Autonomous Prefecture, Yunnan Province, China. The following combination of diagnostic characters serve to distinguish it from all other congeners in the given zoogeographical region: a large processus dentiformes in the upper jaw, a short pre-anus length of 65.4%-66.3% of SL, long paired fins (pectoral: 20.8%-24.2% of SL; pelvic: 17.9%-20.6% of SL), a wide body of 9.7%-11.3% of SL at anal fin origin, an incomplete lateral line, the absence of an orbital lobe, and a broad and distinct basicaudal bar with forward extensions. PMID:25297074

Gait efficiency on an uneven surface is associated with falls and injury in older subjects with a spectrum of lower limb neuromuscular function: a prospective study

PubMed Central

Zurales, Katie; DeMott, Trina K.; Kim, Hogene; Allet, Lara; Ashton-Miller, James A.; Richardson, James K.

2015-01-01

Objective To determine which gait measures on smooth and uneven surfaces predict falls and fall-related injuries in older subjects with diabetic peripheral neuropathy (DPN). Design Twenty-seven subjects (12 women) with a spectrum of peripheral nerve function ranging from normal to moderately severe DPN walked on smooth and uneven surfaces, with gait parameters determined by optoelectronic kinematic techniques. Falls and injuries were then determined prospectively over the following year. Results Seventeen subjects (62.9%) fell and 12 (44.4%) sustained a fall-related injury. As compared to non-fallers, the subject group reporting any fall, as well as the subject group reporting fall-related injury, demonstrated decreased speed, greater step width (SW), shorter step length (SL) and greater step-width-to-step-length ratio (SW:SL) on both surfaces. Uneven surface SW:SL was the strongest predictor of falls (pseudo-R2 = 0.65; p = .012) and remained so with inclusion of other relevant variables into the model. Post-hoc analysis comparing injured with non-injured fallers showed no difference in any gait parameter. Conclusion SW:SL on an uneven surface is the strongest predictor of falls and injuries in older subjects with a spectrum of peripheral neurologic function. Given the relationship between SW:SL and efficiency, older neuropathic patients at increased fall risk appear to sacrifice efficiency for stability on uneven surfaces. PMID:26053187

The Impact of Immediate Verbal Feedback on the Improvement of Swimming Technique

PubMed Central

Zatoń, Krystyna; Szczepan, Stefan

2014-01-01

The present research attempts to ascertain the impact of immediate verbal feedback (IVF) on modifications of stroke length (SL). In all swimming styles, stroke length is considered an essential kinematic parameter of the swimming cycle. It is important for swimming mechanics and energetics. If SL shortens while the stroke rate (SR) remains unchanged or decreases, the temporal-spatial structure of swimming is considered erroneous. It results in a lower swimming velocity. Our research included 64 subjects, who were divided into two groups: the experimental – E (n=32) and the control – C (n=32) groups. A pretest and a post-test were conducted. The subjects swam the front crawl over the test distance of 25m at Vmax. Only the E group subjects were provided with IVF aiming to increase their SL. All tests were filmed by two cameras (50 samples•s-1). The kinematic parameters of the swimming cycle were analyzed using the SIMI Reality Motion Systems 2D software (SIMI Reality Motion Systems 2D GmbH, Germany). The movement analysis allowed to determine the average horizontal swimming velocity over 15 meters. The repeated measures analysis of variance ANOVA with a post-hoc Tukey range test demonstrated statistically significant (p<0.05) differences between the two groups in terms of SL and swimming velocity. IVF brought about a 6.93% (Simi method) and a 5.09% (Hay method) increase in SL, as well as a 2.92% increase in swimming velocity. PMID:25114741

A new species of Abyssobrotula (Ophidiiformes, Ophidiidae) from the Kuril-Kamchatka Trench.

PubMed

Ohashi, Shinpei; Nielsen, Jørgen G

2016-07-01

A new abyssal ophidiid fish, Abyssobrotula hadropercularis, is described on the basis of two specimens caught at two stations at ca. 5000 meters of depth in the Kuril-Kamchatka Trench. The genus Abyssobrotula Nielsen, 1977 was previously known from the type species, A. galatheae Nielsen, 1977 of which 40-50 specimens now are reported from all oceans at depths greater than 2000 m. One of the specimens from the Puerto Rico Trench captured at 8370 m is still the deepest record for fishes. The new species differs from A. galatheae in having great number of pectoral-fin rays 14-15 (vs 10-11); greater eye diameter (1.2-1.3% SL vs 0.7-0.9% SL); larger prepelvic 14.0-14.5% SL (vs 10.5-12.5% SL) and preanal lengths 42.5% SL (vs 33.0-41.5% SL); opercular spine strongly developed (vs poorly developed); gill rakers on anterior arch robust and close-set (vs rakers thin and well separated). The description of A. hadropercularis makes it necessary to slightly modify the generic diagnosis.

The Influence of Added Mass on Optimal Step Length in Running.

PubMed

Reenalda, Jasper; Maas, Maurice T F; de Koning, Jos J

2016-10-01

To examine the influence of induced changes in the morphology of the leg by adding mass on the optimal step length (OSL) in experienced runners to get more insight into parameters that influence preferred step length (PSL) and OSL. Thirteen experienced male runners (mean age 26.9 ± 6.1 y, height 183.7 ± 7.1 cm, mass 71.8 ± 5.9 kg) ran on a treadmill in 3 different conditions: unloaded (UL), loaded with 2 kg mass at the ankles (MA), and loaded with 2 kg mass at the hips (MH) at 7 different step lengths (SLs). SL deviations were expressed as deviations in relative leg length (%LL) from the individual PSL: 0%LL, ±5%LL, ±10%LL, and ±15%LL. Trials lasted 8 min, and 8 min of rest was given between trials. Oxygen uptake (V̇O 2 ) was expressed as a fraction of V̇O 2 at PSL + 0%LL in the unloaded condition (%V̇O 2 ). The %SL with the lowest value of %V̇O 2 was considered the OSL for this group of participants. OSL at the UL condition was 6% shorter than PSL. The MA condition resulted in a 7%LL larger OSL than at UL and MH (P < .05). The mass distribution of the leg is a determinant of the OSL. As a consequence of the added mass to the ankles, OSL was 7%LL longer. Morphological characteristics of the leg might therefore play an important role in determining the runner's individual optimal SL.

Bending Boundary Layers in Laminated-Composite Circular Cylindrical Shells

NASA Technical Reports Server (NTRS)

Nemeth, Michael P.; Smeltzer, Stanley S., III

2000-01-01

A study of the attenuation of bending boundary layers in balanced and unbalanced, symmetrically and unsymmetrically laminated cylindrical shells is presented for nine contemporary material systems. The analysis is based on the linear Sanders-Koiter shell equations and specializations to the Love-Kirchhoff shell equations and Donnell's equations are included. Two nondimensional parameters are identified that characterize the effects of laminate orthotropy and anisotropy on the bending boundary-layer decay length in a very general manner. A substantial number of structural design technology results are presented for a wide range of laminated-composite cylinders. For all laminates considered, the results show that the differences between results obtained with the Sanders-Koiter shell equations, the Love-Kirchhoff shell equations, and Donnell's equations are negligible. The results also show that the effect of anisotropy in the form of coupling between pure bending and twisting has a negligible effect on the size of the bending boundary-layer decay length of the balanced, symmetrically laminated cylinders considered. Moreover, the results show that coupling between the various types of shell anisotropies has a negligible effect on the calculation of the bending boundary-layer decay length in most cases. The results also show that, in some cases, neglecting the shell anisotropy results in underestimating the bending boundary-layer decay length and, in other cases, results in an overestimation.

Nonlinear Response of Thin Cylindrical Shells with Longitudinal Cracks and Subjected to Internal Pressure and Axial compression Loads

NASA Technical Reports Server (NTRS)

Starnes, James H.; Rose, Cheryl A.

1998-01-01

The results of an analytical study of the nonlinear response of a thin unstiffened aluminum cylindrical shell with a longitudinal crack are presented. The shell is analyzed with a nonlinear shell analysis code that maintains the shell in a nonlinear equilibrium state while the crack is grown. The analysis accurately accounts for global and local structural response phenomena. Results are presented for internal pressure, axial compression, and combined internal pressure and axial compression loads. The effects of varying crack length on the nonlinear response of the shell subjected to internal pressure are described. The effects of varying crack length on the prebuckling, buckling and postbuckling responses of the shell subjected to axial compression, and subjected to combined internal pressure and axial compression are also described. The results indicate that the nonlinear interaction between the in-plane stress resultants and the out-of-plane displacements near a crack can significantly affect the structural response of the shell. The results also indicate that crack growth instabilities and shell buckling instabilities can both affect the response of the shell as the crack length is increased.

Fishing and bottom water temperature as drivers of change in maximum shell length in Atlantic surfclams (Spisula solidissima)

NASA Astrophysics Data System (ADS)

Munroe, D. M.; Narváez, D. A.; Hennen, D.; Jacobson, L.; Mann, R.; Hofmann, E. E.; Powell, E. N.; Klinck, J. M.

2016-03-01

Maximum shell length of Atlantic surfclams (Spisula solidissima) on the Middle Atlantic Bight (MAB) continental shelf, obtained from federal fishery survey data from 1982-present, has decreased by 15-20 mm. Two potential causes of this decreasing trend, fishery removal of large animals and stress due to warming bottom temperatures, were investigated using an individual-based model for post-settlement surfclams and a fifty-year hindcast of bottom water temperatures on the MAB. Simulations showed that fishing and/or warming bottom water temperature can cause decreases in maximum surfclam shell length (body size) equivalent to those observed in the fished stock. Independently, either localized fishing rates of 20% or sustained bottom temperatures that are 2 °C warmer than average conditions generate the observed decrease in maximum shell length. However, these independent conditions represent extremes and are not sustained in the MAB. The combined effects of fishing and warmer temperatures can generate simulated length decreases that are similar to observed decreases. Interannual variability in bottom water temperatures can also generate fluctuations in simulated shell length of up to 20 mm over a period of 10-15 years. If the change in maximum size is not genotypic, simulations also suggest that shell size composition of surfclam populations can recover if conditions change; however, that recovery could take a decade to become evident.

Neuromuscular adaptations associated with knee joint angle-specific force change.

PubMed

Noorkõiv, Marika; Nosaka, Kazunori; Blazevich, Anthony J

2014-08-01

Neuromuscular adaptations to joint angle-specific force increases after isometric training have not yet been fully elucidated. This study examined angle-specific neuromuscular adaptations in response to isometric knee extension training at short (SL, joint angle 38.1° ± 3.7°) versus long (LL, 87.5° ± 6.0°) muscle lengths. Sixteen men trained three times a week for 6 wk either at SL (n = 8) or LL (n = 8). Voluntary maximal isometric knee extensor (MVC) force, doublet twitch force, EMG amplitudes (EMG/Mmax), and voluntary activation during MVC force (VA%) were measured at eight knee joint angles (30°-100°) at weeks 0, 3, and 6. Muscle volume and cross-sectional area (CSA) were measured from magnetic resonance imaging scans, and fascicle length (Lf) was assessed using ultrasonography before and after training. Clear joint angle specificity of force increase was seen in SL but not in LL. The 13.4% ± 9.7% (P = 0.01) force increase around the training angle in SL was related to changes in vastus lateralis and vastus medialis EMG/Mmax around the training angle (r = 0.84-0.88, P < 0.05), without changes in the doublet twitch force-angle relation or muscle size. In LL, muscle volume and CSA increased and the changes in CSA at specific muscle regions were correlated with changes in MVC force. A 5.4% ± 4.9% (P = 0.001) increase in Lf found in both groups was not associated with angle-specific force changes. There were no angle-specific changes in VA%. The EMG/Mmax, although not VA%, results suggest that neural adaptations underpinned training-related changes at short quadriceps lengths, but hypertrophic changes predominated after training at long lengths. The findings of this study should contribute to the development of more effective and evidence-based rehabilitation and strength training protocols.

Life history and ecological characteristics of the Santa Ana sucker, Catostomus santaanae

USGS Publications Warehouse

Saiki, Michael K.; Martin, Barbara A.; Knowles, Glen W.; Tennant, Patrick W.

2007-01-01

This study was conducted to document the life history and ecological characteristics of the Santa Ana sucker, Catostomus santaanae, within its native range in southern California. Electrofishing surveys were conducted at 3-month intervals from December 1998 to December 1999 at one site on the San Gabriel River and two sites on the Santa Ana River. Suckers were captured in the San Gabriel River (average, 6.6 fish/10-minutes electrofishing) and at an upstream Santa Ana River site (average, 2.3 fish/10-minutes electrofishing) but not at a downstream Santa Ana River site. Length frequency distributions indicated that at least three year classes (modal groups) of suckers were present in the San Gabriel River, whereas one or two year classes were present in the Santa Ana River. Collection of 21-30 mm standard length (SL) juveniles in June in the Santa Ana River and in September in the San Gabriel River indicated that reproduction occurred over several months. In December, Age-0 suckers averaged 36-48 mm SL in the San Gabriel River and 63-65 mm SL in the Santa Ana River, whereas Age-1 suckers averaged 86 mm SL in the San Gabriel River and 115 mm SL in the Santa Ana River. On average, suckers were in better body condition in the San Gabriel River than in the Santa Ana River. Highest abundance of suckers was associated with relativelypristine environmental conditions (especially low specific conductance) where other native fishes were also common or abundant.

Growth, mortality and reproduction of the blue tilapia Oreochromis aureus (Perciformes: Cichlidae) in the Aguamilpa Reservoir, Mexico.

PubMed

Peña Messina, Emilio; Tapia Varela, Raul; Velázquez Abunader, José Iván; Orbe Mendoza, Alma Araceli; Velazco Arce, Javier Marcial de Jesús Ruiz

2010-12-01

Tilapia production has increased in Aguamilpa Reservoir, in Nayarit, Mexico, in the last few years and represents a good economic activity for rural communities and the country. We determined growth parameters, mortality and reproductive aspects for 2413 specimens of blue tilapia Oreochromis aureus in this reservoir. Samples were taken monthly from July 2000 through June 2001, of which 1 371 were males and 1 042 were females. Standard length (SL) and total weight (TW) were measured in each organism. The SL/TW relationships through power models for sexes were determined. The growth parameters L infinity k, and t0 of the von Bertalanffy equation were estimated using frequency distribution of length through ELEFAN-I computer program. Finally the reproductive cycle and size of first maturity were established using morph chromatic maturity scale. The results suggested that the males and females had negative allometric growth (b < 3). Significant differences were found between SL/TW model for the sexes, suggesting separate models for males and females. Results indicate that there are no differences in growth rates between sexes; the proposed parameters were L infinity = 43.33 cm standard length, k = 0.36/year and t0 = -0.43 years. Natural and fishing mortality coefficients were 0.83/year and 1.10/year, respectively. The estimated exploitation rate (0.57/year) suggested that during the study period the fishery showed signs of overfishing. Blue tilapia reproduces year-round; the highest activity occurs from January through May and size of first maturity was 23 cm SL. We conclude that it is necessary to establish a minimum catch size in this reservoir based on the reproductive behavior of this species.

Morphometric body condition indices of wild Florida manatees (Trichechus manatus latirostris)

USGS Publications Warehouse

Harshaw, Lauren T.; Larkin, Iskande V.; Bonde, Robert K.; Deutsch, Charles J.; Hill, Richard C.

2016-01-01

In many species, body weight (W) increases geometrically with body length (L), so W/L3 provides a body condition index (BCI) that can be used to evaluate nutritional status once a normal range has been established. No such index has been established for Florida manatees (Trichechus manatus latirostris). This study was designed to determine a normal range of BCIs of Florida manatees by comparing W in kg with straight total length (SL), curvilinear total length (CL), and umbilical girth (UG) in m for 146 wild manatees measured during winter health assessments at three Florida locations. Small calves to large adults of SL from 1.47 to 3.23 m and W from 77 to 751 kg were compared. BCIs were significantly greater in adult females than in adult males (p < 0.05). W scaled proportionally to L3 in females but not in males, which were slimmer than females. The logarithms of W and of each linear measurement were regressed to develop amended indices that allow for sex differences. The regression slope for log W against log SL was 2.915 in females and 2.578 in males; W/SL2.915 ranged from 18.9 to 29.6 (mean 23.2) in females and from 24.6 to 37.3 (mean 29.8) in males. Some BCIs were slightly (4%), but significantly (p ≤ 0.05), higher for females in Crystal River than in Tampa Bay or Indian River, but there was no evidence of geographic variation in condition among males. These normal ranges should help evaluate the nutritional status of both wild and rehabilitating captive manatees.

Lamprologus markerti, a new lamprologine cichlid (Teleostei: Cichlidae) endemic to the lower Congo River in the Democratic Republic of Congo, west-central Africa.

PubMed

Tougas, Stephanie; Stiassny, Melanie L J

2014-08-15

A new Lamprologus is described from the lower Congo River (LCR) in the Democratic Republic of Congo. Lamprologus markerti, new species, is readily distinguished from L. tigripictilis and L. werneri, the LCR endemic lamprologines with which it was once taxonomically conflated, in the possession of a reduced number of gill rakers on the first arch (9-11 versus 12-17), a longer head (32.1-34.7% SL versus 29.3-31.9 and 29.1-32.9% SL, respectively), and a longer predorsal length (33.0-35.9% SL versus 29.3-32.7 and 28.5-32.6% SL, respectively). Further, L. markerti lacks a second intestinal loop present in both L. tigripictilis and L. werneri, and has a highly reduced infraorbital series often consisting of a single first infraorbital (lachrymal) element. 

Bending Boundary Layers in Laminated-Composite Circular Cylindrical Shells

NASA Technical Reports Server (NTRS)

Nemeth, Michael P.; Smeltzer, Stanley S., III

2000-01-01

An analytical, parametric study of the attenuation of bending boundary layers or edge effects in balanced and unbalanced, symmetrically and unsymmetrically laminated thin cylindrical shells is presented for nine contemporary material systems. The analysis is based on the linear Sanders-Koiter shell equations and specializations to the Love-Kirchhoff shell equations and Donnell's equations are included. Two nondimensional parameters are identified that characterize and quantify the effects of laminate orthotropy and laminate anisotropy on the bending boundary-layer decay length in a very general and encompassing manner. A substantial number of structural design technology results are presented for a wide range of laminated-composite cylinders. For all the laminate constructions considered, the results show that the differences between results that were obtained with the Sanders-Koiter shell equations, the Love-Kirchhoff shell equations, and Donnell's equations are negligible. The results also show that the effect of anisotropy in the form of coupling between pure bending and twisting has a negligible effect on the size of the bending boundary-layer decay length of the balanced, symmetrically laminated cylinders considered. Moreover, the results show that coupling between the various types of shell anisotropies has a negligible effect on the calculation of the bending boundary-layer decay length in most cases. The results also show that in some cases neglecting the shell anisotropy results in underestimating the bending boundary-layer decay length and in other cases it results in an overestimation.

The cross-bridge dynamics is determined by two length-independent kinetics: Implications on muscle economy and Frank-Starling Law.

PubMed

Amiad Pavlov, Daria; Landesberg, Amir

2016-01-01

The cellular mechanisms underlying the Frank-Starling Law of the heart and the skeletal muscle force-length relationship are not clear. This study tested the effects of sarcomere length (SL) on the average force per cross-bridge and on the rate of cross-bridge cycling in intact rat cardiac trabeculae (n=9). SL was measured by laser diffraction and controlled with a fast servomotor to produce varying initial SLs. Tetanic contractions were induced by addition of cyclopiazonic acid, to maintain a constant activation. Stress decline and redevelopment in response to identical ramp shortenings, starting at various initial SLs, was analyzed. Both stress decline and redevelopment responses revealed two distinct kinetics: a fast and a slower phase. The duration of the rapid phases (4.2 ± 0.1 msec) was SL-independent. The second slower phase depicted a linear dependence of the rate of stress change on the instantaneous stress level. Identical slopes (70.5 ± 1.6 [1/s], p=0.33) were obtained during ramp shortening at all initial SLs, indicating that the force per cross-bridge and cross-bridge cycling kinetics are length-independent. A decrease in the slope at longer SLs was obtained during stress redevelopment, due to internal shortening. The first phase is attributed to rapid changes in the average force per cross-bridge. The second phase is ascribed to both cross-bridge cycling between its strong and weak conformations and to changes in the number of strong cross-bridges. Cross-bridge cycling kinetics and muscle economy are length-independent and the Frank-Starling Law cannot be attributed to changes in the force per cross-bridge or in the single cross-bridge cycling rates. Copyright © 2015 Elsevier Ltd. All rights reserved.

Signal recognition particle RNA in dinoflagellates and the Perkinsid Perkinsus marinus.

PubMed

Zhang, Huan; Campbell, David A; Sturm, Nancy R; Rosenblad, Magnus A; Dungan, Christopher F; Lin, Senjie

2013-09-01

In dinoflagellates and perkinsids, the molecular structure of the protein translocating machinery is unclear. Here, we identified several types of full-length signal recognition particle (SRP) RNA genes from Karenia brevis (dinoflagellate) and Perkinsus marinus (perkinsid). We also identified the four SRP S-domain proteins, but not the two Alu domain proteins, from P. marinus and several dinoflagellates. We mapped both ends of SRP RNA transcripts from K. brevis and P. marinus, and obtained the 3' end from four other dinoflagellates. The lengths of SRP RNA are predicted to be ∼260-300 nt in dinoflagellates and 280-285 nt in P. marinus. Although these SRP RNA sequences are substantially variable, the predicted structures are similar. The genomic organization of the SRP RNA gene differs among species. In K. brevis, this gene is located downstream of the spliced leader (SL) RNA, either as SL RNA-SRP RNA-tRNA gene tandem repeats, or within a SL RNA-SRP RNA-tRNA-U6-5S rRNA gene cluster. In other dinoflagellates, SRP RNA does not cluster with SL RNA or 5S rRNA genes. The majority of P. marinus SRP RNA genes array as tandem repeats without the above-mentioned small RNA genes. Our results capture a snapshot of a potentially complex evolutionary history of SRP RNA in alveolates. Copyright © 2013 Elsevier GmbH. All rights reserved.

Comparative quantitative trait loci for silique length and seed weight in Brassica napus.

PubMed

Fu, Ying; Wei, Dayong; Dong, Hongli; He, Yajun; Cui, Yixin; Mei, Jiaqin; Wan, Huafang; Li, Jiana; Snowdon, Rod; Friedt, Wolfgang; Li, Xiaorong; Qian, Wei

2015-09-23

Silique length (SL) and seed weight (SW) are important yield-associated traits in rapeseed (Brassica napus). Although many quantitative trait loci (QTL) for SL and SW have been identified in B. napus, comparative analysis for those QTL is seldom performed. In the present study, 20 and 21 QTL for SL and SW were identified in doubled haploid (DH) and DH-derived reconstructed F2 populations in rapeseed, explaining 55.1-74.3% and 24.4-62.9% of the phenotypic variation across three years, respectively. Of which, 17 QTL with partially or completely overlapped confidence interval on chromosome A09, were homologous with two overlapped QTL on chromosome C08 by aligning QTL confidence intervals with the reference genomes of Brassica crops. By high density selective genotyping of DH lines with extreme phenotypes, using a Brassica single-nucleotide polymorphism (SNP) array, the QTL on chromosome A09 was narrowed, and aligned into 1.14-Mb region from 30.84 to 31.98 Mb on chromosome R09 of B. rapa and 1.05-Mb region from 27.21 to 28.26 Mb on chromosome A09 of B. napus. The alignment of QTL with Brassica reference genomes revealed homologous QTL on A09 and C08 for SL. The narrowed QTL region provides clues for gene cloning and breeding cultivars by marker-assisted selection.

Effect of feeding sericea lespedeza leaf meal in goats experimentally infected with Haemonchus contortus.

PubMed

Joshi, B R; Kommuru, D S; Terrill, T H; Mosjidis, J A; Burke, J M; Shakya, K P; Miller, J E

2011-05-31

Effect of sericea lespedeza [SL; Lespedeza cuneata (Dum-Cours.) G. Don.] leaf meal feeding was evaluated in two experiments in indoor reared goats with experimental infection of Haemonchus contortus larvae. In the first experiment, ten 8-10 month old male Spanish and Alpine cross kids pair matched for body weight and age were fed SL or bermudagrass [BG; Cynodon dactylon (L.) Pers.] hay one week before infection and were infected with 5000 H. contortus L(3). The animals were maintained on the same diet for the remaining period and were slaughtered 28 days post-infection (DPI) to determine the establishment of incoming infective larvae. Goats fed SL had lower establishment (P<0.05) of H. contortus larvae than that of the control goats fed BG hay. In the second experiment, twenty-five 8-10 months old male Alpine cross, Saanen, Nubian×Saanen and Spanish kids reared in confinement on BG were experimentally infected with 5000 H. contortus L(3). On 35 DPI, the animals were allocated to two groups after blocking by fecal egg count (FEC), and one group was fed SL leaf meal (n=13), and another control group remained on BG (n=12). Four goats/group were slaughtered successively on days 7, 14, and 28 days post SL feeding, except on day 7, when five SL fed goats were slaughtered. Fecal egg counts and blood packed cell volume (PCV) were measured at weekly intervals and worm count, female worm fecundity, worm length and mucosal eosinophils, mast cells and globule leucocytes were measured after slaughter. Goats fed SL had a lower FEC (P<0.05) one week after feeding, as compared to those fed on BG, and the values remained at low level thereafter. Similarly, PCV was also significantly affected by feeding (P<0.01), and feeding and time interaction (P<0.05). However, worm burden, female worm fecundity, parasite length, and mucosal inflammatory cell count were similar between the groups. Feeding SL reduced the establishment of infective larvae and FEC of H. contortus in experimental studies and this plant could be used for biological control of parasite infection under field conditions to limit the harmful effects of the parasites in goats. Copyright © 2010 Elsevier B.V. All rights reserved.

A pollen-specific RALF from tomato that regulates pollen tube elongation.

PubMed

Covey, Paul A; Subbaiah, Chalivendra C; Parsons, Ronald L; Pearce, Gregory; Lay, Fung T; Anderson, Marilyn A; Ryan, Clarence A; Bedinger, Patricia A

2010-06-01

Rapid Alkalinization Factors (RALFs) are plant peptides that rapidly increase the pH of plant suspension cell culture medium and inhibit root growth. A pollen-specific tomato (Solanum lycopersicum) RALF (SlPRALF) has been identified. The SlPRALF gene encodes a preproprotein that appears to be processed and released from the pollen tube as an active peptide. A synthetic SlPRALF peptide based on the putative active peptide did not affect pollen hydration or viability but inhibited the elongation of normal pollen tubes in an in vitro growth system. Inhibitory effects of SlPRALF were detectable at concentrations as low as 10 nm, and complete inhibition was observed at 1 mum peptide. At least 10-fold higher levels of alkSlPRALF, which lacks disulfide bonds, were required to see similar effects. A greater effect of peptide was observed in low-pH-buffered medium. Inhibition of pollen tube elongation was reversible if peptide was removed within 15 min of exposure. Addition of 100 nm SlPRALF to actively growing pollen tubes inhibited further elongation until tubes were 40 to 60 mum in length, after which pollen tubes became resistant to the peptide. The onset of resistance correlated with the timing of the exit of the male germ unit from the pollen grain into the tube. Thus, exogenous SlPRALF acts as a negative regulator of pollen tube elongation within a specific developmental window.

Effects of the chromatic defocus caused by interchange of two monochromatic lights on refraction and ocular dimension in guinea pigs.

PubMed

Qian, Yi-Feng; Dai, Jin-Hui; Liu, Rui; Chen, Min-Jie; Zhou, Xing-Tao; Chu, Ren-Yuan

2013-01-01

To investigate refractive and axial responses to the shift of focal plane resulting from the interchange of two monochromatic lights separately corresponding to the peak wavelengths of the cones absorption spectrum in retina, fifty 2-week-old pigmented guinea pigs were randomly assigned to five groups based on the mode of illumination: short-wavelength light (SL), middle-wavelength light (ML) and broad-band white light (BL) for 20 weeks, SL for 10 weeks followed by ML for 10 weeks (STM), as well as ML for 10 weeks followed by SL for 10 weeks (MTS). Biometric and refractive measurements were then performed every 2 weeks. After 10 weeks, SL and STM groups became more hyperopic and had less vitreous elongation than BL group. However, ML and MTS groups became more myopic and had more vitreous elongation. After interchange of the monochromatic light, the refractive error decreased rapidly by about 1.93D and the vitreous length increased by 0.14 mm in STM group from 10 to 12 weeks. After that, there were no significant intergroup differences between STM and BL groups. The interchange from ML to SL quickly increased the refractive error by about 1.53D and decreased the vitreous length by about 0.13 mm in MTS group after two weeks. At this time, there were also no significant intergroup differences between MTS and BL groups. The guinea pig eye can accurately detect the shift in focal plane caused by interchange of two monochromatic lights and rapidly generate refractive and axial responses. However, an excessive compensation was induced. Some properties of photoreceptors or retina may be changed by the monochromatic light to influence the following refractive development.

Short rest interval lengths between sets optimally enhance body composition and performance with 8 weeks of strength resistance training in older men.

PubMed

Villanueva, Matthew G; Lane, Christianne Joy; Schroeder, E Todd

2015-02-01

To determine if 8 weeks of periodized strength resistance training (RT) utilizing relatively short rest interval lengths (RI) in between sets (SS) would induce greater improvements in body composition and muscular performance, compared to the same RT program utilizing extended RI (SL). 22 male volunteers (SS: n = 11, 65.6 ± 3.4 years; SL: n = 11, 70.3 ± 4.9 years) were assigned to one of two strength RT groups, following 4 weeks of periodized hypertrophic RT (PHRT): strength RT with 60-s RI (SS) or strength RT with 4-min RI (SL). Prior to randomization, all 22 study participants trained 3 days/week, for 4 weeks, targeting hypertrophy; from week 4 to week 12, SS and SL followed the same periodized strength RT program for 8 weeks, with RI the only difference in their RT prescription. Following PHRT, all study participants experienced increases in lean body mass (LBM) (p < 0.01), upper and lower body strength (p < 0.001), and dynamic power (p < 0.001), as well as decreases in percentage body fat (p < 0.05). Across the 8-week strength RT phase, SS experienced significantly greater increases in LBM (p = 0.001), flat machine bench press 1-RM (p < 0.001), bilateral leg press 1-RM (p < 0.001), narrow/neutral grip lat pulldown (p < 0.01), and Margaria stair-climbing power (p < 0.001), compared to SL. This study suggests 8 weeks of periodized high-intensity strength RT with shortened RI induces significantly greater enhancements in body composition, muscular performance, and functional performance, compared to the same RT prescription with extended RI, in older men. Applied professionals may optimize certain RT-induced adaptations, by incorporating shortened RI.

Hand-assisted versus straight laparoscopic sigmoid colectomy on a training simulator: what is the difference? A stepwise comparison of hand-assisted versus straight laparoscopic sigmoid colectomy performance on an augmented reality simulator.

PubMed

Leblanc, Fabien; Delaney, Conor P; Ellis, Clyde N; Neary, Paul C; Champagne, Bradley J; Senagore, Anthony J

2010-12-01

We hypothesized that simulator-generated metrics and intraoperative errors may be able to differentiate the technical differences between hand-assisted laparoscopic (HAL) and straight laparoscopic (SL) approaches. Thirty-eight trainees performed two laparoscopic sigmoid colectomies on an augmented reality simulator, randomly starting by a SL (n = 19) or HAL (n = 19) approach. Both approaches were compared according to simulator-generated metrics, and intraoperative errors were collected by faculty. Sixty-four percent of surgeons were experienced (>50 procedures) with open colon surgery. Fifty-five percent and 69% of surgeons were inexperienced (<10 procedures) with SL and HAL colon surgery, respectively. Time (P < 0.001), path length (P < 0.001), and smoothness (P < 0.001) were lower with the HAL approach. Operative times for sigmoid and splenic flexure mobilization and for the colorectal anastomosis were significantly shorter with the HAL approach. Time to control the vascular pedicle was similar between both approaches. Error rates were similar between both approaches. Operative time, path length, and smoothness correlated directly with the error rate for the HAL approach. In contrast, error rate inversely correlated with the operative time for the SL approach. A HAL approach for sigmoid colectomy accelerated colonic mobilization and anastomosis. The difference in correlation between both laparoscopic approaches and error rates suggests the need for different skills to perform the HAL and the SL sigmoid colectomy. These findings may explain the preference of some surgeons for a HAL approach early in the learning of laparoscopic colorectal surgery.

Mg/Ca ratios of two Globigerinoides ruber (white) morphotypes: Implications for reconstructing past tropical/subtropical surface water conditions

NASA Astrophysics Data System (ADS)

Steinke, Stephan; Chiu, Han-Yi; Yu, Pai-Sen; Shen, Chuan-Chou; LöWemark, Ludvig; Mii, Horng-Sheng; Chen, Min-Te

2005-11-01

Tests of the planktonic foraminifer Globigerinoides ruber (white; d'Orbigny) have become a standard tool for reconstructing past oceanic environments. Paleoceanographers often utilize the Mg/Ca ratios of the foraminiferal tests for reconstructing low-latitude ocean glacial-interglacial changes in sea surface temperatures (SST). We report herein a comparison of Mg/Ca measurements on sample pairs (n = 20) of two G. ruber (white) morphotypes (G. ruber sensu stricto (s.s.) and G. ruber sensu lato (s.l.)) from surface and downcore samples of the western Pacific and Indian Oceans. G. ruber s.s. refers to specimens with spherical chambers sitting symmetrically over previous sutures with a wide, high arched aperture, whereas G. ruber s.l. refers to a more compact test with a diminutive final chamber and small aperture. The G. ruber s.s. specimens generally show significantly higher Mg/Ca ratios compared to G. ruber s.l. Our results from the Mg/Ca ratio analysis suggest that G. ruber s.l. specimens precipitated their shells in slightly colder surface waters than G. ruber s.s. specimens. This conclusion is supported by the differences in δ18O and δ13C values between the two morphotypes. Although it is still unclear if these two morphotypes represent phenotypic variants or sibling species, our findings seem to support the hypothesis of depth and/or seasonal allopatry within a single morphospecies.

Identification of white campion (Silene latifolia) guaiacol O-methyltransferase involved in the biosynthesis of veratrole, a key volatile for pollinator attraction

PubMed Central

2012-01-01

Background Silene latifolia and its pollinator, the noctuid moth Hadena bicruris, represent an open nursery pollination system wherein floral volatiles, especially veratrole (1, 2-dimethoxybenzene), lilac aldehydes, and phenylacetaldehyde are of key importance for floral signaling. Despite the important role of floral scent in ensuring reproductive success in S. latifolia, the molecular basis of scent biosynthesis in this species has not yet been investigated. Results We isolated two full-length cDNAs from S. latifolia that show similarity to rose orcinol O-methyltransferase. Biochemical analysis showed that both S. latifolia guaiacol O-methyltransferase1 (SlGOMT1) &S. latifolia guaiacol O-methyltransferase2 (SlGOMT2) encode proteins that catalyze the methylation of guaiacol to form veratrole. A large Km value difference between SlGOMT1 (~10 μM) and SlGOMT2 (~501 μM) resulted that SlGOMT1 is 31-fold more catalytically efficient than SlGOMT2. qRT-PCR expression analysis showed that the SlGOMT genes are specifically expressed in flowers and male S. latifolia flowers had 3- to 4-folds higher level of GOMT gene transcripts than female flower tissues. Two related cDNAs, S. dioica O-methyltransferase1 (SdOMT1) and S. dioica O-methyltransferase2 (SdOMT2), were also obtained from the sister species Silene dioica, but the proteins they encode did not methylate guaiacol, consistent with the lack of veratrole emission in the flowers of this species. Our evolutionary analysis uncovered that SlGOMT1 and SlGOMT2 genes evolved under positive selection, whereas SdOMT1 and SdOMT2 genes show no evidence for selection. Conclusions Altogether, we report the identification and functional characterization of the gene, SlGOMT1 that efficiently catalyzes veratrole formation, whereas another copy of this gene with only one amino acid difference, SlGOMT2 was found to be less efficient for veratrole synthesis in S. latifolia. PMID:22937972

Effects of the microbubble shell physicochemical properties on ultrasound-mediated drug delivery to the brain.

PubMed

Wu, Shih-Ying; Chen, Cherry C; Tung, Yao-Sheng; Olumolade, Oluyemi O; Konofagou, Elisa E

2015-08-28

Lipid-shelled microbubbles have been used in ultrasound-mediated drug delivery. The physicochemical properties of the microbubble shell could affect the delivery efficiency since they determine the microbubble mechanical properties, circulation persistence, and dissolution behavior during cavitation. Therefore, the aim of this study was to investigate the shell effects on drug delivery efficiency in the brain via blood-brain barrier (BBB) opening in vivo using monodisperse microbubbles with different phospholipid shell components. The physicochemical properties of the monolayer were varied by using phospholipids with different hydrophobic chain lengths (C16, C18, and C24). The dependence on the molecular size and acoustic energy (both pressure and pulse length) were investigated. Our results showed that a relatively small increase in the microbubble shell rigidity resulted in a significant increase in the delivery of 40-kDa dextran, especially at higher pressures. Smaller (3kDa) dextran did not show significant difference in the delivery amount, suggesting that the observed shell effect was molecular size-dependent. In studying the impact of acoustic energy on the shell effects, it was found that they occurred most significantly at pressures causing microbubble destruction (450kPa and 600kPa); by increasing the pulse length to deliver the 40-kDa dextran, the difference between C16 and C18 disappeared while C24 still achieved the highest delivery efficiency. These indicated that the acoustic energy could be used to modulate the shell effects. The acoustic cavitation emission revealed the physical mechanisms associated with different shells. Overall, lipid-shelled microbubbles with long hydrophobic chain length could achieve high delivery efficiency for larger molecules especially with high acoustic energy. Our study, for the first time, offered evidence directly linking the microbubble monolayer shell with their efficacy for drug delivery in vivo. Copyright © 2015 Elsevier B.V. All rights reserved.

Hole effective masses and subband splitting in type-II superlattice infrared detectors

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

Ting, David Z., E-mail: David.Z.Ting@jpl.nasa.gov; Soibel, Alexander; Gunapala, Sarath D.

We explore band structure effects to help determine the suitability of n-type type-II superlattice (T2SL) absorbers for infrared detectors. It is often assumed that the exceedingly large growth-direction band-edge curvature hole effective mass in n-type long wavelength infrared (LWIR) T2SL would lead to low hole mobility and therefore low detector collection quantum efficiency. We computed the thermally averaged conductivity effective mass and show that the LWIR T2SL hole conductivity effective mass along the growth direction can be orders of magnitude smaller than the corresponding band-edge effective mass. LWIR InAs/GaSb T2SL can have significantly smaller growth-direction hole conductivity effective mass thanmore » its InAs/InAsSb counterpart. For the InAs/InAsSb T2SL, higher Sb fraction is more favorable for hole transport. Achieving long hole diffusion length becomes progressively more difficult for the InAs/InAsSb T2SL as the cutoff wavelength increases, since its growth-direction hole conductivity effective mass increases significantly with decreasing band gap. However, this is mitigated by the fact that the splitting between the top valence subbands also increases with the cutoff wavelength, leading to reduced inter-subband scattering and increased relaxation time.« less

Gibberellin Regulation of Fruit Set and Growth in Tomato1[W

PubMed Central

Serrani, Juan Carlos; Sanjuán, Rafael; Ruiz-Rivero, Omar; Fos, Mariano; García-Martínez, José Luis

2007-01-01

The role of gibberellins (GAs) in tomato (Solanum lycopersicum) fruit development was investigated. Two different inhibitors of GA biosynthesis (LAB 198999 and paclobutrazol) decreased fruit growth and fruit set, an effect reversed by GA3 application. LAB 198999 reduced GA1 and GA8 content, but increased that of their precursors GA53, GA44, GA19, and GA20 in pollinated fruits. This supports the hypothesis that GA1 is the active GA for tomato fruit growth. Unpollinated ovaries developed parthenocarpically in response to GA3 > GA1 = GA4 > GA20, but not to GA19, suggesting that GA 20-oxidase activity was limiting in unpollinated ovaries. This was confirmed by analyzing the effect of pollination on transcript levels of SlCPS, SlGA20ox1, -2, and -3, and SlGA3ox1 and -2, encoding enzymes of GA biosynthesis. Pollination increased transcript content of SlGA20ox1, -2, and -3, and SlCPS, but not of SlGA3ox1 and -2. To investigate whether pollination also altered GA inactivation, full-length cDNA clones of genes encoding enzymes catalyzing GA 2-oxidases (SlGA2ox1, -2, -3, -4, and -5) were isolated and characterized. Transcript levels of these genes did not decrease early after pollination (5-d-old fruits), but transcript content reduction of all of them, mainly of SlGA2ox2, was found later (from 10 d after anthesis). We conclude that pollination mediates fruit set by activating GA biosynthesis mainly through up-regulation of GA20ox. Finally, the phylogenetic reconstruction of the GA2ox family clearly showed the existence of three gene subfamilies, and the phylogenetic position of SlGA2ox1, -2, -3, -4, and -5 was established. PMID:17660355

Crack Initiation and Growth Behavior at Corrosion Pit in 2024-T3 Aluminum Alloy

DTIC Science & Technology

2014-09-01

63 Figure B.1: The crack length vs. number of cycles during fatigue testing for the 2AI-01 specimen...number of cycles during fatigue testing for the the 2AI- 02 specimen...64 Figure B.3: The crack length vs. number of cycles during fatigue testing for the 2Sl-01 specimen

Extraction of minority carrier diffusion length of MWIR Type-II superlattice nBp detector

NASA Astrophysics Data System (ADS)

Taghipour, Zahra; Kazemi, Alireza; Myers, Stephen; Wijewarnasuriya, Priyalal; Mathews, Sen; Steenbergen, Elizabeth H.; Morath, Christian; Cowan, Vincent M.; Ariyawansa, Gamini; Scheihing, John; Krishna, Sanjay

2017-08-01

We present a model for the spectral external quantum efficiency (EQE) to extract the minority carrier diffusion length (Ln) of a unipolar nBp InAs/GaSb Type-II superlattice (T2SL) mid-wave infrared (MWIR) detector. The detector consists of a 4 μm thick p-doped 10ML InAs/10ML GaSb SL absorber with a 50% cut-off wavelength of 5 μm at 80 K and zero bias. The n-type doped InAs/AlSb SL barrier in the structure was included to reduce the GR dark current. By fitting the experimentally measured EQE data to the theoretically calculated QE based on the solution of the drift-diffusion equation, the p-type absorber was found the have Ln = 10 +/- 0.5 μm at 80K, and Ln = 12 +/- 0.5 μm at 120K and 150K. We performed the absorption coefficient measurement at different temperatures of interest. Also, we estimated the reduced background concentration and the built-in potential by utilizing a capacitance-voltage measurement technique. We used time-resolved-photoluminescence (TRPL) to determine the lifetime at 80K. With the result of the model and the lifetime measurement, we calculated the diffusion coefficient and the mobility in the T2SL detector at various temperatures. Also, we studied the behavior of different dark current mechanisms by fitting the experimentally measured and simulated dark current density under different operating temperatures and biases.

Lower extremity joint loads in habitual rearfoot and mid/forefoot strike runners with normal and shortened stride lengths.

PubMed

Boyer, Elizabeth R; Derrick, Timothy R

2018-03-01

Our purpose was to compare joint loads between habitual rearfoot (hRF) and habitual mid/forefoot strikers (hFF), rearfoot (RFS) and mid/forefoot strike (FFS) patterns, and shorter stride lengths (SLs). Thirty-eight hRF and hFF ran at their normal SL, 5% and 10% shorter, as well as with the opposite foot strike. Three-dimensional ankle, knee, patellofemoral (PF) and hip contact forces were calculated. Nearly all contact forces decreased with a shorter SL (1.2-14.9% relative to preferred SL). In general, hRF had higher PF (hRF-RFS: 10.8 ± 1.4, hFF-FFS: 9.9 ± 2.0 BWs) and hip loads (axial hRF-RFS: -9.9 ± 0.9, hFF-FFS: -9.6 ± 1.0 BWs) than hFF. Many loads were similar between foot strike styles for the two groups, including axial and lateral hip, PF, posterior knee and shear ankle contact forces. Lateral knee and posterior hip contact forces were greater for RFS, and axial ankle and knee contact forces were greater for FFS. The tibia may be under greater loading with a FFS because of these greater axial forces. Summarising, a particular foot strike style does not universally decrease joint contact forces. However, shortening one's SL 10% decreased nearly all lower extremity contact forces, so it may hold potential to decrease overuse injuries associated with excessive joint loads.

A novel cold-adapted and highly salt-tolerant esterase from Alkalibacterium sp. SL3 from the sediment of a soda lake

PubMed Central

Wang, Guozeng; Wang, Qiaohuang; Lin, Xianju; Bun Ng, Tzi; Yan, Renxiang; Lin, Juan; Ye, Xiuyun

2016-01-01

A novel esterase gene (estSL3) was cloned from the Alkalibacterium sp. SL3, which was isolated from the sediment of soda lake Dabusu. The 636-bp full-length gene encodes a polypeptide of 211 amino acid residues that is closely related with putative GDSL family lipases from Alkalibacterium and Enterococcus. The gene was successfully expressed in E. coli, and the recombinant protein (rEstSL3) was purified to electrophoretic homogeneity and characterized. rEstSL3 exhibited the highest activity towards pNP-acetate and had no activity towards pNP-esters with acyl chains longer than C8. The enzyme was highly cold-adapted, showing an apparent temperature optimum of 30 °C and remaining approximately 70% of the activity at 0 °C. It was active and stable over the pH range from 7 to 10, and highly salt-tolerant up to 5 M NaCl. Moreover, rEstSL3 was strongly resistant to most tested metal ions, chemical reagents, detergents and organic solvents. Amino acid composition analysis indicated that EstSL3 had fewer proline residues, hydrogen bonds and salt bridges than mesophilic and thermophilic counterparts, but more acidic amino acids and less hydrophobic amino acids when compared with other salt-tolerant esterases. The cold active, salt-tolerant and chemical-resistant properties make it a promising enzyme for basic research and industrial applications. PMID:26915906

Improved Modeling of Surface Layer Parameters in a AGCM Using Refined Vertical Resolution in the Surface Layer

NASA Astrophysics Data System (ADS)

Shin, H. H.; Zhao, M.; Ming, Y.; Chen, X.; Lin, S. J.

2017-12-01

Surface layer (SL) parameters in atmospheric models - such as 2-m air temperature (T2), 10-m wind speed (U10), and surface turbulent fluxes - are computed by applying the Monin-Obukhov Similarity Theory (MOST) to the lowest model level height (LMH) in the models. The underlying assumption is that LMH is within surface layer height (SLH), but most AGCMs hardly meet the condition in stable boundary layers (SBLs) over land. To assess the errors in modeled SL parameters caused by this, offline computations of the MOST are performed with different LMHs from 1 to 100 m, for an idealized SBL case with prescribed surface parameters (surface temperature, roughness length and Obukhov length), and vertical profiles of temperature and winds. The results show that when LMH is higher than SLH, T2 and U10 are underestimated by O(1 K) and O(1 m/s), respectively, and the biases increase as LMH increases. Based on this, the refined vertical resolution with an additional layer in the SL is applied to the GFDL AGCM, and it reduces the systematic cold biases in T2 and the systematic underestimation of U10.

Stream gradient Hotspot and Cluster Analysis (SL-HCA) for improving the longitudinal profiles metrics

NASA Astrophysics Data System (ADS)

Troiani, Francesco; Piacentini, Daniela; Seta Marta, Della

2016-04-01

Many researches successfully focused on stream longitudinal profiles analysis through Stream Length-gradient (SL) index for detecting, at different spatial scales, either tectonic structures or hillslope processes. The analysis and interpretation of spatial variability of SL values, both at a regional and local scale, is often complicated due to the concomitance of different factors generating SL anomalies, including the bedrock composition. The creation of lithologically-filtered SL maps is often problematic in areas where homogeneously surveyed geological maps, with a sufficient resolution are unavailable. Moreover, both the SL map classification and the unbiased anomaly detection are rather difficult. For instance, which is the best threshold to define the anomalous SL values? Further, is there a minimum along-channel extent of anomalous SL values for objectively defining over-steeped segments on long-profiles? This research investigates the relevance and potential of a new approach based on Hotspot and Cluster Analysis of SL values (SL-HCA) for detecting knickzones on long-profiles at a regional scale and for fine-tuning the interpretation of their geological-geomorphological meaning. We developed this procedure within a 2800 km2-wide area located in the mountainous sector of the Northern Apennines of Italy. The Getis-Ord Gi∗ statistic is applied for the SL-HCA approach. The value of SL, calculated starting from a 5x5 m Digital Elevation Model, is used as weighting factor and the Gi∗ index is calculated for each 50 m-long channel segment for the whole fluvial system. The outcomes indicate that high positive Gi∗ values imply the clustering of SL anomalies, thus the occurrence of knickzones on the stream long-profiles. Results show that high and very high Gi* values (i.e. values beyond two standard deviations from the mean) correlate well with the principal knickzones detected with existent lithologically-filtered SL maps. Field checks and remote sensing analysis conducted on 52 clusters of high and very high Gi* values indicate that mass movement of slope material represents the dominant process producing over-steeped long-profiles along connected streams, whereas the litho-structure accounts for the main anomalies along disconnected steams. Tectonic structures generally provide to the largest clusters. Our results demonstrate that SL-HCA maps have the same potential of lithologically-filtered SL maps for detecting knickzones due to hillslope processes and/or tectonic structures. The reduced-complexity model derived from SL-HCA approach highly improve the readability of the morphometric outcomes, thus the interpretation at a regional scale of the geological-geomorphological meaning of over-steeped segments on long-profiles. SL-HCA maps are useful to investigate and better interpret knickzones within regions poorly covered by geological data and where field surveys are difficult to be performed.

Biometrical analysis of the shoulder joint regarding glenoid implant dimensions for arthroplasty.

PubMed

Kircher, Jörn; Bittersohl, Bernd; Zilkens, Christoph; Hedtmann, Achim; Krauspe, Rüdiger

2014-05-01

Reduced bone stock and difficult intraoperative orientation are challenges in glenoid replacement surgery. New implant designs and methods for fixation, such as locking screws, extra-long central pegs and/or central compression screws are targeting these issues. The objective of this study is the analysis of the glenoid dimension regarding maximum central peg diameter and peg length (PL), and maximum screw length (SL) for glenoid fixation. Retrospective analysis of magnetic resonance imaging (n = 50) scans. Measurement of the maximum inferior glenoid diameter (GD), SL, maximum length of a 9.9, 10 and 11.4 mm central peg (PL) in the transverse plane; glenoid version (GV), humeral head diameter (HHD). Two independent measurements. Mean age: 49.0 ± 15.7 years (17-80) (n = 20 female, 49.6 ± 16.0; n = 30 male, 48.6 ± 15.7). Mean values of measurement were GD: 28.9 ± 3.7 mm (21-39); SL: 34.1 ± 4.9 mm (26-44); PL 9.9 mm: 19.4 ± 4.3 mm (9-30); PL 10 mm: 19.0 ± 4.4 mm (8-30); PL 11.4 mm: 16.5 ± 4.1 mm (7-26) with significant gender differences (p = 0.001; p = 0.022; p = 0.001); GV: -0.6° ± 4.9° (-10 to 11); HHD: 50.0 mm ± 4.9 (41-61). There was good correlation between PL and SL (r = 0.32, p = 0.024) and for GD and PL (r = 0.61, p = 0.001; r = 0.57, p = 0.001; r = 0.96, p = 0.001). The ratio of HHD and GD was very constant with 0.6 ± 0.07. These data indicate the high interindividual variability of glenoid morphology including significant gender-related differences. The good correlation between humeral head size and GD and maximum central PL can be helpful for cases with reduced bone stock in decision-making about implant size and bone grafting.

The MADS-box gene SlMBP11 regulates plant architecture and affects reproductive development in tomato plants.

PubMed

Guo, Xuhu; Chen, Guoping; Naeem, Muhammad; Yu, Xiaohu; Tang, Boyan; Li, Anzhou; Hu, Zongli

2017-05-01

MADS-domain proteins are important transcription factors that are involved in many biological processes of plants. In the present study, SlMBP11, a member of the AGL15 subfamily, was cloned in tomato plants (Solanum lycopersicon M.). SlMBP11 is ubiquitously expressed in all of the tissues we examined, whereas the SlMBP11 transcription levels were significantly higher in reproductive tissues than in vegetative tissues. Plants exhibiting increased SlMBP11 levels displayed reduced plant height, leaf size, and internode length as well as a loss of dominance in young seedlings, highly branched growth from each leaf axil, and increased number of nodes and leaves. Moreover, overexpression lines also exhibited reproductive phenotypes, such as those having a shorter style and split ovary, leading to polycarpous fruits, while the wild type showed normal floral organization. In addition, delayed perianth senescence was observed in transgenic tomatoes. These phenotypes were further confirmed by analyzing the morphological, anatomical and molecular features of lines exhibiting overexpression. These results suggest that SlMBP11 plays an important role in regulating plant architecture and reproductive development in tomato plants. These findings add a new class of transcription factors to the group of genes controlling axillary bud growth and illuminate a previously uncharacterized function of MADS-box genes in tomato plants. Copyright © 2017 Elsevier B.V. All rights reserved.

The Role of Endogenous Strigolactones and Their Interaction with ABA during the Infection Process of the Parasitic Weed Phelipanche ramosa in Tomato Plants

PubMed Central

Cheng, Xi; Floková, Kristýna; Bouwmeester, Harro; Ruyter-Spira, Carolien

2017-01-01

The root parasitic plant species Phelipanche ramosa, branched broomrape, causes severe damage to economically important crops such as tomato. Its seed germination is triggered by host-derived signals upon which it invades the host root. In tomato, strigolactones (SLs) are the main germination stimulants for P. ramosa. Therefore, the development of low SL-producing lines may be an approach to combat the parasitic weed problem. However, since SLs are also a plant hormone controlling many aspects of plant development, SL deficiency may also have an effect on post-germination stages of the infection process, during the parasite-host interaction. In this study, we show that SL-deficient tomato plants (Solanum lycopersicum; SlCCD8 RNAi lines), infected with pre-germinated P. ramosa seeds, display an increased infection level and faster development of the parasite, which suggests a positive role for SLs in the host defense against parasitic plant invasion. Furthermore, we show that SL-deficient tomato plants lose their characteristic SL-deficient phenotype during an infection with P. ramosa through a reduction in the number of internodes and the number and length of secondary branches. Infection with P. ramosa resulted in increased levels of abscisic acid (ABA) in the leaves and roots of both wild type and SL-deficient lines. Upon parasite infection, the level of the conjugate ABA-glucose ester (ABA-GE) also increased in leaves of both wild type and SL-deficient lines and in roots of one SL-deficient line. The uninfected SL-deficient lines had a higher leaf ABA-GE level than the wild type. Despite the high levels of ABA, stomatal aperture and water loss rate were not affected by parasite infection in the SL-deficient line, while in wild type tomato stomatal aperture and water loss increased upon infection. Future studies are needed to further underpin the role that SLs play in the interaction of hosts with parasitic plants and which other plant hormones interact with the SLs during this process. PMID:28392795

The Role of Endogenous Strigolactones and Their Interaction with ABA during the Infection Process of the Parasitic Weed Phelipanche ramosa in Tomato Plants.

PubMed

Cheng, Xi; Floková, Kristýna; Bouwmeester, Harro; Ruyter-Spira, Carolien

2017-01-01

The root parasitic plant species Phelipanche ramosa , branched broomrape, causes severe damage to economically important crops such as tomato. Its seed germination is triggered by host-derived signals upon which it invades the host root. In tomato, strigolactones (SLs) are the main germination stimulants for P. ramosa . Therefore, the development of low SL-producing lines may be an approach to combat the parasitic weed problem. However, since SLs are also a plant hormone controlling many aspects of plant development, SL deficiency may also have an effect on post-germination stages of the infection process, during the parasite-host interaction. In this study, we show that SL-deficient tomato plants ( Solanum lycopersicum; SlCCD8 RNAi lines), infected with pre-germinated P. ramosa seeds, display an increased infection level and faster development of the parasite, which suggests a positive role for SLs in the host defense against parasitic plant invasion. Furthermore, we show that SL-deficient tomato plants lose their characteristic SL-deficient phenotype during an infection with P. ramosa through a reduction in the number of internodes and the number and length of secondary branches. Infection with P. ramosa resulted in increased levels of abscisic acid (ABA) in the leaves and roots of both wild type and SL-deficient lines. Upon parasite infection, the level of the conjugate ABA-glucose ester (ABA-GE) also increased in leaves of both wild type and SL-deficient lines and in roots of one SL-deficient line. The uninfected SL-deficient lines had a higher leaf ABA-GE level than the wild type. Despite the high levels of ABA, stomatal aperture and water loss rate were not affected by parasite infection in the SL-deficient line, while in wild type tomato stomatal aperture and water loss increased upon infection. Future studies are needed to further underpin the role that SLs play in the interaction of hosts with parasitic plants and which other plant hormones interact with the SLs during this process.

Identification of larvae: The zebra mussel (Dreissena polymorpha), quagga mussel (Dreissena rosteriformis bugensis), and Asian clam (Corbicula fluminea)

USGS Publications Warehouse

Nichols, S. Jerrine; Black, M.G.

1994-01-01

There are presently four freshwater bivalves in the United States that produce larvae or veligers commonly found in the water column: two forms of Asian clams and two species of dreissenids. Portions of the geographic range of three of these bivalves, one species of Asian clam (Corbicula fluminea), zebra mussels (Dreissena polymorpha), and quagga mussels (Dreissena rosteriformis bugensis), overlap, causing problems with larval identification. To determine which characteristics can be used to separate larval forms, adult Asian clams, quaggas, and zebra mussels were brought into the laboratory and induced to spawn, and the resulting larvae were reared. Hybrids between quaggas and zebra mussels were also produced, but not reared to maturity. Characteristics allowing for the most rapid and accurate separation of larvae were hinge length, shell length/height, shell shape, shell size, and the presence or absence of a foot and velum. These characteristics were observed in laboratory-reared larvae of known parentage and field-caught larvae of unknown parentage. In most cases, larvae of the Asian clam can be readily separated from those produced by either type of dreissenid on the basis of shell size and presence of a foot. Separating the gametes and embryos of the two types of dreissenids is not possible, but after shell formation, most of the larval stages can be distinguished. Hinge length, shell length/height, and the similarity in size of the shell valves can be used to separate straight-hinged, umbonal, pediveliger, and plantigrade larvae. Quagga × zebra mussel hybrids show characteristics of both parents and are difficult to identify.

Species and Size Composition of Seahorses (Genus Hippocampus, Family Syngnathidae) in the Coastal Waters and Local Market of Kota Kinabalu, Sabah, Malaysia

PubMed Central

Shapawi, Rossita; Anyie, Adrian Leslie; Hussien, Muhammad Ali Syed; Zuldin, Wahidatul Husna

2015-01-01

Seahorse diversity (genus Hippocampus, Family Syngnathidae), species identification, size composition and sexual dimorphism were studied from November 2012 to March 2013 in selected coastal waters around Kota Kinabalu, Sabah and the local market trade. Six species of seahorses were identified in the study: (1) Hippocampus barbouri, (2) Hippocampus comes, (3) Hippocampus kelloggi, (4) Hippocampus kuda, (5) Hippocampus spinosissimus and (6) Hippocampus trimaculatus. All six species were sold at the local market, and the dried seahorses were obtained mainly by local fishermen using trawl by-catch method and traded as traditional medicine, souvenirs and other uses. Four species were identified by direct samplings in various different habitats of Kota Kinabalu coastal waters: (1) H. barbouri, (2) H. comes, (3) H. kuda, and (4) H. spinosissimus. Based on the results, H. comes was the largest in size among the four fresh/live species found (mean standard length [SL]: 148.25±1.26 mm), whereas H. barbouri was the smallest species (mean SL: 129±7.81 mm). For the dried samples, H. kelloggi was the largest (mean SL: 245.25±14.55 mm) and H. barbouri was the smallest (mean SL: 127.21±10.01 mm). No significant difference (p>0.05) was observed between the lengths of males and females in every seahorse species, and there was no sexual size dimorphism in any of the species. The findings from the study are significant to provide baseline data for the conservation efforts of these unique marine teleost. PMID:26868706

Species and Size Composition of Seahorses (Genus Hippocampus, Family Syngnathidae) in the Coastal Waters and Local Market of Kota Kinabalu, Sabah, Malaysia.

PubMed

Shapawi, Rossita; Anyie, Adrian Leslie; Hussien, Muhammad Ali Syed; Zuldin, Wahidatul Husna

2015-12-01

Seahorse diversity (genus Hippocampus, Family Syngnathidae), species identification, size composition and sexual dimorphism were studied from November 2012 to March 2013 in selected coastal waters around Kota Kinabalu, Sabah and the local market trade. Six species of seahorses were identified in the study: (1) Hippocampus barbouri, (2) Hippocampus comes, (3) Hippocampus kelloggi, (4) Hippocampus kuda, (5) Hippocampus spinosissimus and (6) Hippocampus trimaculatus. All six species were sold at the local market, and the dried seahorses were obtained mainly by local fishermen using trawl by-catch method and traded as traditional medicine, souvenirs and other uses. Four species were identified by direct samplings in various different habitats of Kota Kinabalu coastal waters: (1) H. barbouri, (2) H. comes, (3) H. kuda, and (4) H. spinosissimus. Based on the results, H. comes was the largest in size among the four fresh/live species found (mean standard length [SL]: 148.25±1.26 mm), whereas H. barbouri was the smallest species (mean SL: 129±7.81 mm). For the dried samples, H. kelloggi was the largest (mean SL: 245.25±14.55 mm) and H. barbouri was the smallest (mean SL: 127.21±10.01 mm). No significant difference (p>0.05) was observed between the lengths of males and females in every seahorse species, and there was no sexual size dimorphism in any of the species. The findings from the study are significant to provide baseline data for the conservation efforts of these unique marine teleost.

Contribution of titin and extracellular matrix to passive pressure and measurement of sarcomere length in the mouse left ventricle

PubMed Central

Chung, Charles S; Granzier, Henk L

2011-01-01

It remains to be established to what degree titin and the extracellular matrix (ECM) contribute to passive pressure in the left ventricle (LV). Thus, we aimed to elucidate the contribution of major molecular determinants of passive pressure in the normal mouse LV. Furthermore, we determined the working sarcomere length (SL) range of the LV to bridge our findings to earlier work in skinned muscle fibers. We utilized Frank-Starling type protocols to obtain diastolic pressure-volume relationships (PVR) in Langendorff perfused isolated LVs. To quantify the molecular contribution of titin and ECM, we innovated on methods of fiber mechanics to chemically permeabilize intact LVs and measure a fully passive PVR. To differentially dissect the contributions of the ECM and titin, we utilized myofilament extraction techniques in permeabilized LVs, measuring passive PVRs at each stage in the protocol. Myofilament extraction suggests that titin contributes ~80% of passive pressures in the heart. Langendorff perfusion was also used to chemically fix passive and BaCl2 activated hearts at specific volumes to determine that the maximal working SL range of the midwall LV fibers is approximately 1.8-2.2 μm. A model of the passive SL-Volume relationship was then used to estimate the pressure-SL relationships, indicating that the ECM contribution does not exceed titin's contribution until large volumes with SLs>~2.2μm. In conclusion, within physiological volumes titin is the dominant contributor to LV passive pressure, and ECM-based pressures dominates at larger volumes. PMID:21255582

Flux-periodicity crossover from h/2e to h/e in aluminium nano-loops

NASA Astrophysics Data System (ADS)

Espy, C.; Sharon, O. J.; Braun, J.; Garreis, R.; Strigl, F.; Shaulov, A.; Leiderer, P.; Scheer, E.; Yeshurun, Y.

2018-03-01

We study the magnetoresistance of aluminium ‘double-networks’ formed by connecting the vertexes of nano-loops with relatively long wires, creating two interlaced subnetworks of small and large loops (SL and LL, respectively). Far below the critical temperature, Aharonov-Bohm like quantum interference effects are observed for both the LL and the SL subnetworks. When approaching T c, both exhibit the usual Little-Parks oscillations, with periodicity of the superconducting flux quantum Φ 0 =h/2e. For one sample, with a relatively large coherence length, ξ, at temperatures very close to T c, the Φ 0 periodicity of the SL disappears, and the waveform of the first period is consistent with that predicted recently for loops with a size a < ξ, indicating a crossover to 2Φ 0 periodicity.

a Triangular Deformation of the Two-Dimensional POINCARÉ Algebra

NASA Astrophysics Data System (ADS)

Khorrami, M.; Shariati, A.; Abolhassani, M. R.; Aghamohammadi, A.

Contracting the h-deformation of SL(2, ℝ), we construct a new deformation of two-dimensional Poincaré's algebra, the algebra of functions on its group and its differential structure. It is seen that these dual Hopf algebras are isomorphic to each other. It is also shown that the Hopf algebra is triangular, and its universal R-matrix is also constructed explicitly. We then find a deformation map for the universal enveloping algebra, and at the end, give the deformed mass shells and Lorentz transformation.

A circumferential crack in a cylindrical shell under tension.

NASA Technical Reports Server (NTRS)

Duncan-Fama, M. E.; Sanders, J. L., Jr.

1972-01-01

A closed cylindrical shell under uniform internal pressure has a slit around a portion of its circumference. Linear shallow shell theory predicts inverse square-root-type singularities in certain of the stresses at the crack tips. This paper reports the computed strength of these singularities for different values of a dimensionless parameter based on crack length, shell radius and shell thickness.

Surgical management of breast cancer liver metastases

PubMed Central

Cassera, Maria A; Hammill, Chet W; Ujiki, Michael B; Wolf, Ronald F; Swanström, Lee L; Hansen, Paul D

2011-01-01

Introduction Selected patients with isolated breast cancer liver metastases (BCLM) may benefit from surgical management; however, indications remain unclear and the risks may outweigh the benefits in patients with a generally poor prognosis. Methods Between 1998 and 2006, 17 patients diagnosed with BCLM were considered for surgical management (<4 tumours, tumour <4 cm in diameter and no/stable extrahepatic metastases). Peri-operative and outcomes data were analysed and compared. Results Eight patients were found to have extensive or untreatable disease on staging laparoscopy and intra-operative ultrasound (SL/IOUS). The remaining nine patients underwent surgical management [seven laparoscopic radiofrequency ablations (RFA) and two hepatic resections]. Median length of follow-up for patients treated surgically was 40.0 months, median disease-free survival (DFS) was 32.2 months and median time to disease progression was 17.7 months. Of the eight patients not amenable to surgery, median length of follow-up was 21.8 months. Conclusion SL/IOUS prevented unnecessary laparotomy in half of the patients taken to the operating room for surgical treatment of BCLM. In patients with BCLM, SL/IOUS should be considered standard of care before surgical intervention. The small number of patients and short follow-up may be inadequate to determine the true value of surgical management in this group of patients with BCLM. PMID:21418133

Genetic Diversity of Anopheles triannulatus s.l. (Diptera: Culicidae) from Northwestern and Southeastern Colombia

PubMed Central

Rosero, Doris A.; Jaramillo, Luz M.; Gutiérrez, Lina A.; Conn, Jan E.; Correa, Margarita M.

2012-01-01

Anopheles triannulatus s.l. is a species complex, however in Colombia its taxonomic status is unclear. This study was conducted to understand the level of genetic differentiation or population structure of specimens of An. triannulatus s.l. from northwestern and southeastern Colombia. Cytochrome oxidase subunit I (COI) and internal transcribed spacer (ITS2) sequence analyses suggested high genetic differentiation between the NW and SE populations. A TCS network and Bayesian inference analysis based on 814 bp of COI showed two main groups: group I included samples from the NW and group II samples from the SE. Two main ITS2-polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) patterns were found. Pattern I is present in both the NW and SE, and pattern II is found in the SE specimens. To further elucidate the taxonomic status of An. triannulatus s.l. in Colombia and how these COI lineages are related to the Triannulatus Complex species, the evaluation of immature stages, male genitalia, and additional mitochondrial and nuclear markers will be needed. PMID:22949519

Genetic diversity of Anopheles triannulatus s.l. (Diptera: Culicidae) from northwestern and southeastern Colombia.

PubMed

Rosero, Doris A; Jaramillo, Luz M; Gutiérrez, Lina A; Conn, Jan E; Correa, Margarita M

2012-11-01

Anopheles triannulatus s.l. is a species complex, however in Colombia its taxonomic status is unclear. This study was conducted to understand the level of genetic differentiation or population structure of specimens of An. triannulatus s.l. from northwestern and southeastern Colombia. Cytochrome oxidase subunit I (COI) and internal transcribed spacer (ITS2) sequence analyses suggested high genetic differentiation between the NW and SE populations. A TCS network and Bayesian inference analysis based on 814 bp of COI showed two main groups: group I included samples from the NW and group II samples from the SE. Two main ITS2-polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) patterns were found. Pattern I is present in both the NW and SE, and pattern II is found in the SE specimens. To further elucidate the taxonomic status of An. triannulatus s.l. in Colombia and how these COI lineages are related to the Triannulatus Complex species, the evaluation of immature stages, male genitalia, and additional mitochondrial and nuclear markers will be needed.

NMR structure of the 101-nucleotide core encapsidation signal of the Moloney murine leukemia virus.

PubMed

D'Souza, Victoria; Dey, Anwesha; Habib, Dina; Summers, Michael F

2004-03-19

The full length, positive-strand genome of the Moloney Murine Leukemia Virus contains a "core encapsidation signal" that is essential for efficient genome packaging during virus assembly. We have determined the structure of a 101-nucleotide RNA that contains this signal (called mPsi) using a novel isotope-edited NMR approach. The method is robust and should be generally applicable to larger RNAs. mPsi folds into three stem loops, two of which (SL-C and SL-D) co-stack to form an extended helix. The third stem loop (SL-B) is connected to SL-C by a flexible, four-nucleotide linker. The structure contains five mismatched base-pairs, an unusual C.CG base-triple platform, and a novel "A-minor K-turn," in which unpaired adenosine bases A340 and A341 of a GGAA bulge pack in the minor groove of a proximal stem, and a bulged distal uridine (U319) forms a hydrogen bond with the phosphodiester of A341. Phylogenetic analyses indicate that these essential structural elements are conserved among the murine C-type retroviruses.

Shell-corona microgels from double interpenetrating networks.

PubMed

Rudyak, Vladimir Yu; Gavrilov, Alexey A; Kozhunova, Elena Yu; Chertovich, Alexander V

2018-04-18

Polymer microgels with a dense outer shell offer outstanding features as universal carriers for different guest molecules. In this paper, microgels formed by an interpenetrating network comprised of collapsed and swollen subnetworks are investigated using dissipative particle dynamics (DPD) computer simulations, and it is found that such systems can form classical core-corona structures, shell-corona structures, and core-shell-corona structures, depending on the subchain length and molecular mass of the system. The core-corona structures consisting of a dense core and soft corona are formed at small microgel sizes when the subnetworks are able to effectively separate in space. The most interesting shell-corona structures consist of a soft cavity in a dense shell surrounded with a loose corona, and are found at intermediate gel sizes; the area of their existence depends on the subchain length and the corresponding mesh size. At larger molecular masses the collapsing network forms additional cores inside the soft cavity, leading to the core-shell-corona structure.

Capoeta coadi, a new species of cyprinid fish from the Karun River drainage, Iran based on morphological and molecular evidences (Teleostei, Cyprinidae)

PubMed Central

Alwan, Nisreen H.; Zareian, Halimeh; Esmaeili, Hamid Reza

2016-01-01

Abstract As presently recognized, the genus Capoeta includes 24 species, nine of which are known to occur in Iran (Capoeta aculeata, Capoeta capoeta, Capoeta buhsei, Capoeta damascina, Capoeta fusca, Capoeta heratensis, Capoeta mandica, Capoeta saadii and Capoeta trutta) and are distributed in almost all Iranian basins except Sistan and Mashkid. Capoeta coadi sp. n. is a new species from the Karun River, southern Iran, draining into the Arvand Rud (Shatt al-Arab) which drains into the Persian Gulf. It is distinguished from all other species of Capoeta by the combination of the following characters: elongate and usually cylindrical body; 8–9 branched dorsal-fin rays; last unbranched dorsal-fin ray weakly to moderately ossified and serrated along 1/3–2/3 of its length; scales small; 70-84 in lateral line (total); 12–17 scales between dorsal-fin origin and lateral line; 9-11 scales between anal-fin origin and lateral line; 26–32 circum-peduncular scales; 10–13 gill rakers on lower limb of first gill arch; 45–47 total vertebrae; one posterior pair of barbels; bright golden-greenish or silvery body coloration in life; length of the longest dorsal-fin ray 15–22% SL; head length 23–26% SL; mouth width 7–10% SL. Capoeta coadi is also distinguished from all other congeners in the Iranian drainages by fixed diagnostic nucleotide substitutions in the mtDNA COI barcode region and cyt b. It is nested in the Capoeta damascina species complex. PMID:28050161

Spliced leader RNA of trypanosomes: in vivo mutational analysis reveals extensive and distinct requirements for trans splicing and cap4 formation.

PubMed Central

Lücke, S; Xu, G L; Palfi, Z; Cross, M; Bellofatto, V; Bindereif, A

1996-01-01

In trypanosomes mRNAs are generated through trans splicing. The spliced leader (SL) RNA, which donates the 5'-terminal mini-exon to each of the protein coding exons, plays a central role in the trans splicing process. We have established in vivo assays to study in detail trans splicing, cap4 modification, and RNP assembly of the SL RNA in the trypanosomatid species Leptomonas seymouri. First, we found that extensive sequences within the mini-exon are required for SL RNA function in vivo, although a conserved length of 39 nt is not essential. In contrast, the intron sequence appears to be surprisingly tolerant to mutation; only the stem-loop II structure is indispensable. The asymmetry of the sequence requirements in the stem I region suggests that this domain may exist in different functional conformations. Second, distinct mini-exon sequences outside the modification site are important for efficient cap4 formation. Third, all SL RNA mutations tested allowed core RNP assembly, suggesting flexible requirements for core protein binding. In sum, the results of our mutational analysis provide evidence for a discrete domain structure of the SL RNA and help to explain the strong phylogenetic conservation of the mini-exon sequence and of the overall SL RNA secondary structure; they also suggest that there may be certain differences between trans splicing in nematodes and trypanosomes. This approach provides a basis for studying RNA-RNA interactions in the trans spliceosome. Images PMID:8861965

Ambulatory estimation of foot placement during walking using inertial sensors.

PubMed

Martin Schepers, H; van Asseldonk, Edwin H F; Baten, Chris T M; Veltink, Peter H

2010-12-01

This study proposes a method to assess foot placement during walking using an ambulatory measurement system consisting of orthopaedic sandals equipped with force/moment sensors and inertial sensors (accelerometers and gyroscopes). Two parameters, lateral foot placement (LFP) and stride length (SL), were estimated for each foot separately during walking with eyes open (EO), and with eyes closed (EC) to analyze if the ambulatory system was able to discriminate between different walking conditions. For validation, the ambulatory measurement system was compared to a reference optical position measurement system (Optotrak). LFP and SL were obtained by integration of inertial sensor signals. To reduce the drift caused by integration, LFP and SL were defined with respect to an average walking path using a predefined number of strides. By varying this number of strides, it was shown that LFP and SL could be best estimated using three consecutive strides. LFP and SL estimated from the instrumented shoe signals and with the reference system showed good correspondence as indicated by the RMS difference between both measurement systems being 6.5 ± 1.0 mm (mean ± standard deviation) for LFP, and 34.1 ± 2.7 mm for SL. Additionally, a statistical analysis revealed that the ambulatory system was able to discriminate between the EO and EC condition, like the reference system. It is concluded that the ambulatory measurement system was able to reliably estimate foot placement during walking. Copyright © 2010 Elsevier Ltd. All rights reserved.

Treatment options for tank farms long-length contaminated equipment

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

Josephson, W.S.

1995-10-16

This study evaluated a variety of treatment and disposal technologies for mixed waste (MW) meeting the following criteria: 1. Single-Shell and Double-Shell Tank System (tank farms) equipment and other debris; 2. length greater than 12 feet; and contaminated with listed MW from the tank farms. This waste stream, commonly referred to as tank farms long-length contaminated equipment (LLCE), poses a unique and costly set of challenges during all phases of the waste management lifecycle.

Sarcomere mechanics in uniform and non-uniform cardiac muscle: a link between pump function and arrhythmias.

PubMed

ter Keurs, Henk E D J; Shinozaki, Tsuyoshi; Zhang, Ying Ming; Zhang, Mei Luo; Wakayama, Yuji; Sugai, Yoshinao; Kagaya, Yutaka; Miura, Masahito; Boyden, Penelope A; Stuyvers, Bruno D M; Landesberg, Amir

2008-01-01

Starling's Law and the well-known end-systolic pressure-volume relationship (ESPVR) of the left ventricle reflect the effect of sarcomere length (SL) on stress (sigma) development and shortening by myocytes in the uniform ventricle. We show here that tetanic contractions of rat cardiac trabeculae exhibit a sigma-SL relationship at saturating [Ca2+] that depends on sarcomere geometry in a manner similar to skeletal sarcomeres and the existence of opposing forces in cardiac muscle shortened below slack length. The sigma-SL-[Ca2+]free relationships (sigma-SL-CaR) at submaximal [Ca2+] in intact and skinned trabeculae were similar, albeit that the sensitivity for Ca2+ of intact muscle was higher. We analyzed the mechanisms underlying the sigma-SL-CaR using a kinetic model where we assumed that the rates of Ca2+ binding by Troponin-C (Tn-C) and/or cross-bridge (XB) cycling are determined by SL, [Ca2+] or stress. We analyzed the correlation between the model results and steady state stress measurements at varied SL and [Ca2+] from skinned rat cardiac trabeculae to test the hypotheses that: (i) the dominant feedback mechanism is SL, stress or [Ca2+]-dependent; and (ii) the feedback mechanism regulates: Tn-C-Ca2+ affinity, XB kinetics or, unitary XB-force. The analysis strongly suggests that feedback of the number of strong XBs to cardiac Tn-C-Ca2+ affinity is the dominant mechanism that regulates XB recruitment. Application of this concept in a mathematical model of twitch-stress accurately reproduced the sigma-SL-CaR and the time course of twitch-stress as well as the time course of intracellular [Ca2+]i. Modeling of the response of the cardiac twitch to rapid stress changes using the above feedback model uniquely predicted the occurrence of [Ca2+]i transients as a result of accelerated Ca2+ dissociation from Tn-C. The above concept has important repercussions for the non-uniformly contracting heart in which arrhythmogenic Ca2+ waves arise from weakened areas in cardiac muscle. These Ca2+ waves can reversibly be induced in muscle with non-uniform excitation contraction coupling (ECC) by the cycle of stretch and release in the border zone between the damaged and intact regions. Stimulus trains induced propagating Ca2+ waves and reversibly induced arrhythmias. We hypothesize that rapid force loss by sarcomeres in the border zone during relaxation causes Ca2+ release from Tn-C and initiates Ca2+ waves propagated by the sarcoplasmic reticulum (SR). These observations suggest the unifying hypothesis that force feedback to Ca2+ binding by Tn-C is responsible for Starling's Law and the ESPVR in uniform myocardium and leads in non-uniform myocardium to a surge of Ca2+ released by the myofilaments during relaxation, which initiates arrhythmogenic propagating Ca2+ release by the SR.

Nonlinear Local Bending Response and Bulging Factors for Longitudinal and Circumferential Cracks in Pressurized Cylindrical Shells

NASA Technical Reports Server (NTRS)

Young, Richard D.; Rose, Cheryl A.; Starnes, James H., Jr.

2000-01-01

Results of a geometrically nonlinear finite element parametric study to determine curvature correction factors or bulging factors that account for increased stresses due to curvature for longitudinal and circumferential cracks in unstiffened pressurized cylindrical shells are presented. Geometric parameters varied in the study include the shell radius, the shell wall thickness, and the crack length. The major results are presented in the form of contour plots of the bulging factor as a function of two nondimensional parameters: the shell curvature parameter, lambda, which is a function of the shell geometry, Poisson's ratio, and the crack length; and a loading parameter, eta, which is a function of the shell geometry, material properties, and the applied internal pressure. These plots identify the ranges of the shell curvature and loading parameters for which the effects of geometric nonlinearity are significant. Simple empirical expressions for the bulging factor are then derived from the numerical results and shown to predict accurately the nonlinear response of shells with longitudinal and circumferential cracks. The numerical results are also compared with analytical solutions based on linear shallow shell theory for thin shells, and with some other semi-empirical solutions from the literature, and limitations on the use of these other expressions are suggested.

Bivalve shell horizons in seafloor pockmarks of the last glacial-interglacial transition: a thousand years of methane emissions in the Arctic Ocean

NASA Astrophysics Data System (ADS)

Ambrose, William G.; Panieri, Giuliana; Schneider, Andrea; Plaza-Faverola, Andreia; Carroll, Michael L.; Åström, Emmelie K. L.; Locke, William L.; Carroll, JoLynn

2015-12-01

We studied discrete bivalve shell horizons in two gravity cores from seafloor pockmarks on the Vestnesa Ridge (˜1200 m water depth) and western Svalbard (79°00' N, 06°55' W) to provide insight into the temporal and spatial dynamics of seabed methane seeps. The shell beds, dominated by two genera of the family Vesicomyidae: Phreagena s.l. and Isorropodon sp., were 20-30 cm thick and centered at 250-400 cm deep in the cores. The carbon isotope composition of inorganic (δ13C from -13.02‰ to +2.36‰) and organic (δ13C from -29.28‰ to -21.33‰) shell material and a two-end member mixing model indicate that these taxa derived between 8% and 43% of their nutrition from chemosynthetic bacteria. In addition, negative δ13C values for planktonic foraminifera (-6.7‰ to -3.1‰), concretions identified as methane-derived authigenic carbonates, and pyrite-encrusted fossil worm tubes at the shell horizons indicate a sustained paleo-methane seep environment. Combining sedimentation rates with 14C ages for bivalve material from the shell horizons, we estimate the horizons persisted for about 1000 years between approximately 17,707 and 16,680 years B.P. (corrected). The seepage event over a 1000 year time interval was most likely associated with regional stress-related faulting and the subsequent release of overpressurized fluids.

Shoreline oiling effects and recovery of salt marsh macroinvertebrates from the Deepwater Horizon Oil Spill

PubMed Central

Fleeger, John W.; Bourgoin, Stefan M.; Mendelssohn, Irving A.; Lin, Qianxin; Hou, Aixin

2017-01-01

Salt marshes in northern Barataria Bay, Louisiana, USA were oiled, sometimes heavily, in the aftermath of the Deepwater Horizon oil spill. Previous studies indicate that fiddler crabs (in the genus Uca) and the salt marsh periwinkle (Littoraria irrorata) were negatively impacted in the short term by the spill. Here, we detail longer-term effects and recovery from moderate and heavy oiling over a 3-year span, beginning 30 months after the spill. Although neither fiddler crab burrow density nor diameter differed between oiled and reference sites when combined across all sampling events, these traits differed among some individual sampling periods consistent with a pattern of lingering oiling impacts. Periwinkle density, however, increased in all oiling categories and shell-length groups during our sampling period, and periwinkle densities were consistently highest at moderately oiled sites where Spartina alterniflora aboveground biomass was highest. Periwinkle shell length linearly increased from a mean of 16.5 to 19.2 mm over the study period at reference sites. In contrast, shell lengths at moderately oiled and heavily oiled sites increased through month 48 after the spill, but then decreased. This decrease was associated with a decline in the relative abundance of large adults (shell length 21–26 mm) at oiled sites which was likely caused by chronic hydrocarbon toxicity or oil-induced effects on habitat quality or food resources. Overall, the recovery of S. alterniflora facilitated the recovery of fiddler crabs and periwinkles. However, our long-term record not only indicates that variation in periwinkle mean shell length and length-frequency distributions are sensitive indicators of the health and recovery of the marsh, but agrees with synoptic studies of vegetation and infaunal communities that full recovery of heavily oiled sites will take longer than 66 months. PMID:28828273

Shoreline oiling effects and recovery of salt marsh macroinvertebrates from the Deepwater Horizon Oil Spill.

PubMed

Deis, Donald R; Fleeger, John W; Bourgoin, Stefan M; Mendelssohn, Irving A; Lin, Qianxin; Hou, Aixin

2017-01-01

Salt marshes in northern Barataria Bay, Louisiana, USA were oiled, sometimes heavily, in the aftermath of the Deepwater Horizon oil spill. Previous studies indicate that fiddler crabs (in the genus Uca ) and the salt marsh periwinkle ( Littoraria irrorata) were negatively impacted in the short term by the spill. Here, we detail longer-term effects and recovery from moderate and heavy oiling over a 3-year span, beginning 30 months after the spill. Although neither fiddler crab burrow density nor diameter differed between oiled and reference sites when combined across all sampling events, these traits differed among some individual sampling periods consistent with a pattern of lingering oiling impacts. Periwinkle density, however, increased in all oiling categories and shell-length groups during our sampling period, and periwinkle densities were consistently highest at moderately oiled sites where Spartina alterniflora aboveground biomass was highest. Periwinkle shell length linearly increased from a mean of 16.5 to 19.2 mm over the study period at reference sites. In contrast, shell lengths at moderately oiled and heavily oiled sites increased through month 48 after the spill, but then decreased. This decrease was associated with a decline in the relative abundance of large adults (shell length 21-26 mm) at oiled sites which was likely caused by chronic hydrocarbon toxicity or oil-induced effects on habitat quality or food resources. Overall, the recovery of S. alterniflora facilitated the recovery of fiddler crabs and periwinkles. However, our long-term record not only indicates that variation in periwinkle mean shell length and length-frequency distributions are sensitive indicators of the health and recovery of the marsh, but agrees with synoptic studies of vegetation and infaunal communities that full recovery of heavily oiled sites will take longer than 66 months.

Quantitative investigation on the critical thickness of the dielectric shell for metallic nanoparticles determined by the plasmon decay length.

PubMed

Li, Anran; Lim, Xinyi; Guo, Lin; Li, Shuzhou

2018-04-20

Inert dielectric shells coating the surface of metallic nanoparticles (NPs) are important for enhancing the NPs' stability, biocompatibility, and realizing targeting detection, but they impair NPs' sensing ability due to the electric fields damping. The dielectric shell not only determines the distance of the analyte from the NP surface, but also affects the field decay. From a practical point of view, it is extremely important to investigate the critical thickness of the shell, beyond which the NPs are no longer able to effectively detect the analytes. The plasmon decay length of the shell-coated NPs determines the critical thickness of the coating layer. Extracting from the exponential fitting results, we quantitatively demonstrate that the critical thickness of the shell exhibits a linear dependence on the NP volume and the dielectric constants of the shell and the surrounding medium, but only with a small variation influenced by the NP shape where the dipole resonance is dominated. We show the critical thickness increases with enlarging the NP sizes, or increasing the dielectric constant differences between the shell and surrounding medium. The findings are essential for applications of shell-coated NPs in plasmonic sensing.

Quantitative investigation on the critical thickness of the dielectric shell for metallic nanoparticles determined by the plasmon decay length

NASA Astrophysics Data System (ADS)

Li, Anran; Lim, Xinyi; Guo, Lin; Li, Shuzhou

2018-04-01

Inert dielectric shells coating the surface of metallic nanoparticles (NPs) are important for enhancing the NPs’ stability, biocompatibility, and realizing targeting detection, but they impair NPs’ sensing ability due to the electric fields damping. The dielectric shell not only determines the distance of the analyte from the NP surface, but also affects the field decay. From a practical point of view, it is extremely important to investigate the critical thickness of the shell, beyond which the NPs are no longer able to effectively detect the analytes. The plasmon decay length of the shell-coated NPs determines the critical thickness of the coating layer. Extracting from the exponential fitting results, we quantitatively demonstrate that the critical thickness of the shell exhibits a linear dependence on the NP volume and the dielectric constants of the shell and the surrounding medium, but only with a small variation influenced by the NP shape where the dipole resonance is dominated. We show the critical thickness increases with enlarging the NP sizes, or increasing the dielectric constant differences between the shell and surrounding medium. The findings are essential for applications of shell-coated NPs in plasmonic sensing.

In situ control of synchronous germanide/silicide reactions with Ge/Si core/shell nanowires to monitor formation and strain evolution in abrupt 2.7 nm channel length

DOE PAGES

Chen, Renjie; Nguyen, Binh-Minh; Tang, Wei; ...

2017-05-22

The metal-semiconductor interface in self-aligned contact formation can determine the overall performance of nanoscale devices. This interfacial morphology is predicted and well researched in homogenous semiconductor nanowires (NWs) but was not pursued in heterostructured core/shell nanowires. Here, we found here that the solid-state reactions between Ni and Ge/Si core/shell nanowires resulted in a protruded and a leading NiSiy segment into the channel. A single Ni 2Ge/NiSi y to Ge/Si core/shell interface was achieved by the selective shell removal near the Ni source/drain contact areas. In using in situ transmission electron microscopy, we measured the growth rate and anisotropic strain evolutionmore » in ultra-short channels. We also found elevated compressive strains near the interface between the compound contact and the NW and relatively lower strains near the center of the channel which increased exponentially below the 10 nm channel length to exceed 10% strain at ~3 nm lengths. These compressive strains are expected to result in a non-homogeneous energy band structure in Ge/Si core/shell NWs below 10 nm and potentially benefit their transistor performance.« less

Long-term impacts of human harvesting on shellfish: North Iberian top shells and limpets from the Upper Palaeolithic to the present

NASA Astrophysics Data System (ADS)

Turrero, Pablo; Muñoz-Colmenero, A. Marta; Prado, Andrea; Garcia-Vazquez, Eva

2014-11-01

Humans have contributed to phenotypic and demographic changes in their prey from very early on in the colonization of Europe, including the harvesting of shellfish in coastal ecosystems. We estimated trends in population growth (variation in the number of individuals) from DNA sequences of modern specimens in two North Iberian molluscs, top shells (Osilinus lineatus, from 24 sequences and 14 haplotypes) and limpets (Patella vulgata, taken from the bibliography), which were subjected to very different levels of harvesting pressure during the Upper Palaeolithic (~ 20000 to ~ 6000 years ago). The less harvested Osilinus top shells experienced fluctuations in population numbers coincident with climatic oscillations. Patella limpets, which were harvested in greater numbers, suffered clear and uninterrupted decreases in their numbers during the Upper Palaeolithic. These trends coincided with morphological changes in shell size (length or width) in the same direction (i.e., shell size decreased when population size decreased and vice versa). The differing trends seen in taxa subjected to different intensities of harvesting pressure suggest that climate effects were overcome by anthropogenic selection (leading to a smaller average length) in limpets. We suggest that intense fishing pressure may have induced irreversible shell length decreases in the most exploited species.

In situ control of synchronous germanide/silicide reactions with Ge/Si core/shell nanowires to monitor formation and strain evolution in abrupt 2.7 nm channel length

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

Chen, Renjie; Nguyen, Binh-Minh; Tang, Wei

The metal-semiconductor interface in self-aligned contact formation can determine the overall performance of nanoscale devices. This interfacial morphology is predicted and well researched in homogenous semiconductor nanowires (NWs) but was not pursued in heterostructured core/shell nanowires. Here, we found here that the solid-state reactions between Ni and Ge/Si core/shell nanowires resulted in a protruded and a leading NiSiy segment into the channel. A single Ni 2Ge/NiSi y to Ge/Si core/shell interface was achieved by the selective shell removal near the Ni source/drain contact areas. In using in situ transmission electron microscopy, we measured the growth rate and anisotropic strain evolutionmore » in ultra-short channels. We also found elevated compressive strains near the interface between the compound contact and the NW and relatively lower strains near the center of the channel which increased exponentially below the 10 nm channel length to exceed 10% strain at ~3 nm lengths. These compressive strains are expected to result in a non-homogeneous energy band structure in Ge/Si core/shell NWs below 10 nm and potentially benefit their transistor performance.« less

A comparison of the solvation structure and dynamics of the lithium ion in linear organic carbonates with different alkyl chain lengths.

PubMed

Fulfer, K D; Kuroda, D G

2017-09-20

The structure and dynamics of electrolytes composed of lithium hexafluorophosphate (LiPF 6 ) in dimethyl carbonate, ethyl methyl carbonate, and diethyl carbonate were investigated using a combination of linear and two-dimensional infrared spectroscopies. The solutions studied here have a LiPF 6 concentration of X(LiPF 6 ) = 0.09, which is typically found in commercial lithium ion batteries. This study focuses on comparing the differences in the solvation shell structure and dynamics produced by linear organic carbonates of different alkyl chain lengths. The IR experiments show that either linear carbonate forms a tetrahedral solvation shell (coordination number of 4) around the lithium ion irrespective of whether the solvation shell has anions in close proximity to the carbonates. Moreover, analysis of the absorption cross sections via FTIR and DFT computations reveals a distortion in the angle formed by Li + -O[double bond, length as m-dash]C which decreases from the expected 180° when the alkyl chains of the carbonate are lengthened. In addition, our findings also reveal that, likely due to its asymmetric structure, ethyl methyl carbonate has a significantly more distorted tetrahedral lithium ion solvation shell than either of the other two investigated carbonates. IR photon echo studies further demonstrate that the motions of the solvation shell have a time scale of a few picoseconds for all three linear carbonates. Interestingly, a slowdown of the in place-motions of the first solvation shell is observed when the carbonate has a longer alkyl chain length irrespective of the symmetry. In addition, vibrational energy transfer with a time scale of tens of picoseconds is observed between strongly coupled modes arising from the solvation shell structure of the Li + which corroborates the modeling of these solvation shells in terms of highly coupled vibrational states. Results of this study provide new insights into the molecular structure and dynamics of the lithium ion electrolyte components as a function of solvent structure.

A new species of Hyphessobrycon (Characiformes, Characidae) from the upper Guaviare River, Orinoco River Basin, Colombia

PubMed Central

García-Alzate, Carlos A.; Urbano-Bonilla, Alexander; Taphorn, Donald C.

2017-01-01

Abstract Hyphessobrycon klausanni sp. n. is described from small drainages of the upper Guaviare River (Orinoco River Basin) in Colombia. It differs from all congeners by having a wide, conspicuous, dark lateral stripe extending from the anterior margin of the eye across the body and continued through the middle caudal-fin rays, and that covers (vertically) three or four horizontal scale rows. It also differs by having an orange-yellow stripe extending from the anterosuperior margin of the eye to the caudal peduncle above the lateral line in life. It differs from all other species of Hyphessobrycon that have a similar dark lateral stripe: H. cyanotaenia, H. loretoensis, H. melanostichos, H. nigricinctus, H. herbertaxelrodi, H. eschwartzae, H. montogoi, H. psittacus, H. metae, H. margitae, H. vanzolinii, and H. peruvianus in having only three or four pored scales in the lateral line, 21 to 24 lateral scales and six teeth in the inner premaxillary row. Hyphessobrycon klausanni differs from H. loretoensis in having seven to eight maxillary teeth (vs. three to four) and in having a longer caudal peduncle (12.4–17.0% SL vs. 4.6–8.0% SL). Additionally Hyphessobrycon klausanni can be distinguished from the other species of Hyphessobrycon with a dark lateral stripe from the Orinoco River Basin (H. metae and H. acaciae) in having two teeth in the outer premaxillary row (vs. three to four) and 10 branched pectoral–fin rays (vs. 11 to 12). It further differs from H. metae by the length of the snout (17.6–22.8% HL vs. 9.9–15.2% HL) and by the length of the caudal peduncle (12.4–17.0% SL vs. 7.3–11.8% SL). PMID:28769647

Step-by-step variability of swing phase trajectory area during steady state walking at a range of speeds

PubMed Central

Hurt, Christopher P.; Brown, David A.

2018-01-01

Background Step kinematic variability has been characterized during gait using spatial and temporal kinematic characteristics. However, people can adopt different trajectory paths both between individuals and even within individuals at different speeds. Single point measures such as minimum toe clearance (MTC) and step length (SL) do not necessarily account for the multiple paths that the foot may take during the swing phase to reach the same foot fall endpoint. The purpose of this study was to test a step-by-step foot trajectory area (SBS-FTA) variability measure that is able to characterize sagittal plane foot trajectories of varying areas, and compare this measure against MTC and SL variability at different speeds. We hypothesize that the SBS-FTA variability would demonstrate increased variability with speed. Second, we hypothesize that SBS-FTA would have a stronger curvilinear fit compared with the CV and SD of SL and MTC. Third, we hypothesize SBS-FTA would be more responsive to change in the foot trajectory at a given speed compared to SL and MTC. Fourth, SBS-FTA variability would not strongly co-vary with SL and MTC variability measures since it represents a different construct related to foot trajectory area variability. Methods We studied 15 nonimpaired individuals during walking at progressively faster speeds. We calculated SL, MTC, and SBS-FTA area. Results SBS-FTA variability increased with speed, had a stronger curvilinear fit compared with the CV and SD of SL and MTC, was more responsive at a given speed, and did not strongly co-vary with SL and MTC variability measures. Conclusion SBS foot trajectory area variability was sensitive to change with faster speeds, captured a relationship that the majority of the other measures did not demonstrate, and did not co-vary strongly with other measures that are also components of the trajectory. PMID:29370202

Difference in receptor usage between severe acute respiratory syndrome (SARS) coronavirus and SARS-like coronavirus of bat origin.

PubMed

Ren, Wuze; Qu, Xiuxia; Li, Wendong; Han, Zhenggang; Yu, Meng; Zhou, Peng; Zhang, Shu-Yi; Wang, Lin-Fa; Deng, Hongkui; Shi, Zhengli

2008-02-01

Severe acute respiratory syndrome (SARS) is caused by the SARS-associated coronavirus (SARS-CoV), which uses angiotensin-converting enzyme 2 (ACE2) as its receptor for cell entry. A group of SARS-like CoVs (SL-CoVs) has been identified in horseshoe bats. SL-CoVs and SARS-CoVs share identical genome organizations and high sequence identities, with the main exception of the N terminus of the spike protein (S), known to be responsible for receptor binding in CoVs. In this study, we investigated the receptor usage of the SL-CoV S by combining a human immunodeficiency virus-based pseudovirus system with cell lines expressing the ACE2 molecules of human, civet, or horseshoe bat. In addition to full-length S of SL-CoV and SARS-CoV, a series of S chimeras was constructed by inserting different sequences of the SARS-CoV S into the SL-CoV S backbone. Several important observations were made from this study. First, the SL-CoV S was unable to use any of the three ACE2 molecules as its receptor. Second, the SARS-CoV S failed to enter cells expressing the bat ACE2. Third, the chimeric S covering the previously defined receptor-binding domain gained its ability to enter cells via human ACE2, albeit with different efficiencies for different constructs. Fourth, a minimal insert region (amino acids 310 to 518) was found to be sufficient to convert the SL-CoV S from non-ACE2 binding to human ACE2 binding, indicating that the SL-CoV S is largely compatible with SARS-CoV S protein both in structure and in function. The significance of these findings in relation to virus origin, virus recombination, and host switching is discussed.

Biomechanics of Step Initiation After Balance Recovery With Implications for Humanoid Robot Locomotion.

PubMed

Miller Buffinton, Christine; Buffinton, Elise M; Bieryla, Kathleen A; Pratt, Jerry E

2016-03-01

Balance-recovery stepping is often necessary for both a human and humanoid robot to avoid a fall by taking a single step or multiple steps after an external perturbation. The determination of where to step to come to a complete stop has been studied, but little is known about the strategy for initiation of forward motion from the static position following such a step. The goal of this study was to examine the human strategy for stepping by moving the back foot forward from a static, double-support position, comparing parameters from normal step length (SL) to those from increasing SLs to the point of step failure, to provide inspiration for a humanoid control strategy. Healthy young adults instrumented with joint reflective markers executed a prescribed-length step from rest while marker positions and ground reaction forces (GRFs) were measured. The participants were scaled to the Gait2354 model in opensim software to calculate body kinematic and joint kinetic parameters, with further post-processing in matlab. With increasing SL, participants reduced both static and push-off back-foot GRF. Body center of mass (CoM) lowered and moved forward, with additional lowering at the longer steps, and followed a path centered within the initial base of support (BoS). Step execution was successful if participants gained enough forward momentum at toe-off to move the instantaneous capture point (ICP) to within the BoS defined by the final position of both feet on the front force plate. All lower extremity joint torques increased with SL except ankle joint. Front knee work increased dramatically with SL, accompanied by decrease in back-ankle work. As SL increased, the human strategy changed, with participants shifting their CoM forward and downward before toe-off, thus gaining forward momentum, while using less propulsive work from the back ankle and engaging the front knee to straighten the body. The results have significance for human motion, suggesting the upper limit of the SL that can be completed with back-ankle push-off before additional knee flexion and torque is needed. For biped control, the results support stability based on capture-point dynamics and suggest strategy for center-of-mass trajectory and distribution of ground force reactions that can be compared with robot controllers for initiation of gait after recovery steps.

Thermal Cyclic Resistance Polyester Resin Composites Reinforce Fiber Nut Shell

NASA Astrophysics Data System (ADS)

Fahmi, Hendriwan

2017-12-01

The purpose of study is to determine the effect of fiber length and thermal cyclic of the bending strength of polyester resin composite reinforced by fibers nut shell. The materials used in this study is a nut shell fibers with fiber length of 1 cm, 2 cm and 3 cm and polyester resin with composition 70-30%wt. Fiber nut shell treated soaking in NaOH 30% for 30 minutes, then rinse with clean water so that the fiber free of alkali and then dried. Furthermore, the composite is heated in an oven to a temperature of 100°C for 1 hour and then cooled in the open with a variety of thermal cyclic 30, 40, and 50 times. Bending properties of composites known through the testing process using a three-point bending test equipment universal testing machine. The test results show that the bending strength bending highest in fiber length of 3 cm with 30 treatment cycles of thermal to the value of 53.325 MPa, while the lowest occurred in bending strength fiber length of 1 cm with no cycles of thermal treatment to the value of 30.675 MPa.

Heterozygosity and fitness: No strong association in Great Lakes populations of the zebra mussel, Dreissena Polymorpha (Pallas)

USGS Publications Warehouse

Lewis, K.M.; Feder, J.L.; Horvath, T.G.; Lamberti, G.A.

2000-01-01

A number of studies have found positive associations between allozyme heterozygosity and fitness surrogates (e.g., body size and growth rate) for marine molluscs. We investigated whether similar relationships exist for freshwater populations of the zebra mussel, Dreissena polymorpha. Only one significant correlation between multi-locus heterozygosity and shell length was observed for a total of 22 D. polymorpha populations surveyed from midwestern U.S.A. lakes and streams, and the result was not significant on a table-wide basis. Meta-analysis revealed a significant common correlation coefficient (effect magnitude) between multi-locus heterozygosity and shell length across all 22 sites (rc = 0.052, P = 0.019, 1557 df). However, the variance in shell length explained by multi-locus heterozygosity was small (rc2 = 0.0027), implying a weak causal relationship if any. Also, we saw no relationship between heterozygosity and growth rate in a one-year field enclosure experiment. A significant heterozygosity-shell length correlation previously reported for a zebra mussel population at Put-in-Bay, Lake Erie, Ohio, may have been the product of unique population dynamics, rather than natural selection. Similar demographic considerations may contribute to inconsistencies in heterozygosity-fitness correlations seen for other molluscs.

Do climate variables and human density affect Achatina fulica (Bowditch) (Gastropoda: Pulmonata) shell length, total weight and condition factor?

PubMed

Albuquerque, F S; Peso-Aguiar, M C; Assunção-Albuquerque, M J T; Gálvez, L

2009-08-01

The length-weight relationship and condition factor have been broadly investigated in snails to obtain the index of physical condition of populations and evaluate habitat quality. Herein, our goal was to describe the best predictors that explain Achatina fulica biometrical parameters and well being in a recently introduced population. From November 2001 to November 2002, monthly snail samples were collected in Lauro de Freitas City, Bahia, Brazil. Shell length and total weight were measured in the laboratory and the potential curve and condition factor were calculated. Five environmental variables were considered: temperature range, mean temperature, humidity, precipitation and human density. Multiple regressions were used to generate models including multiple predictors, via model selection approach, and then ranked with AIC criteria. Partial regressions were used to obtain the separated coefficients of determination of climate and human density models. A total of 1.460 individuals were collected, presenting a shell length range between 4.8 to 102.5 mm (mean: 42.18 mm). The relationship between total length and total weight revealed that Achatina fulica presented a negative allometric growth. Simple regression indicated that humidity has a significant influence on A. fulica total length and weight. Temperature range was the main variable that influenced the condition factor. Multiple regressions showed that climatic and human variables explain a small proportion of the variance in shell length and total weight, but may explain up to 55.7% of the condition factor variance. Consequently, we believe that the well being and biometric parameters of A. fulica can be influenced by climatic and human density factors.

Strong Lensing Analysis of the Galaxy Cluster MACS J1319.9+7003 and the Discovery of a Shell Galaxy

NASA Astrophysics Data System (ADS)

Zitrin, Adi

2017-01-01

We present a strong-lensing (SL) analysis of the galaxy cluster MACS J1319.9+7003 (z = 0.33, also known as Abell 1722), as part of our ongoing effort to analyze massive clusters with archival Hubble Space Telescope (HST) imaging. We spectroscopically measured with Keck/Multi-Object Spectrometer For Infra-Red Exploration (MOSFIRE) two galaxies multiply imaged by the cluster. Our analysis reveals a modest lens, with an effective Einstein radius of {θ }e(z=2)=12+/- 1\\prime\\prime , enclosing 2.1+/- 0.3× {10}13 M⊙. We briefly discuss the SL properties of the cluster, using two different modeling techniques (see the text for details), and make the mass models publicly available (ftp://wise-ftp.tau.ac.il/pub/adiz/MACS1319/). Independently, we identified a noteworthy, young shell galaxy (SG) system forming around two likely interacting cluster members, 20″ north of the brightest cluster galaxy. SGs are rare in galaxy clusters, and indeed, a simple estimate reveals that they are only expected in roughly one in several dozen, to several hundred, massive galaxy clusters (the estimate can easily change by an order of magnitude within a reasonable range of characteristic values relevant for the calculation). Taking advantage of our lens model best-fit, mass-to-light scaling relation for cluster members, we infer that the total mass of the SG system is ˜ 1.3× {10}11 {M}⊙ , with a host-to-companion mass ratio of about 10:1. Despite being rare in high density environments, the SG constitutes an example to how stars of cluster galaxies are efficiently redistributed to the intra-cluster medium. Dedicated numerical simulations for the observed shell configuration, perhaps aided by the mass model, might cast interesting light on the interaction history and properties of the two galaxies. An archival HST search in galaxy cluster images can reveal more such systems.

Application of the line-spring model to a cylindrical shell containing a circumferential or axial part-through crack

NASA Technical Reports Server (NTRS)

Delale, F.; Erdogan, F.

1982-01-01

The line-spring model developed by Rice and Levy (1972) is used to obtain an approximate solution for a cylindrical shell containing a part-through surface crack. A Reissner type theory is used to account for the effects of the transverse shear deformations, and the stress intensity factor at the deepest penetration point of the crack is tabulated for bending and membrane loading by varying three-dimensionless length parameters of the problem formed from the shell radius, the shell thickness, the crack length, and the crack depth. The upper bounds of the stress intensity factors are provided, and qualitatively the line-spring model gives the expected results in comparison with elasticity solutions.

Free Vibration of Fiber Composite Thin Shells in a Hot Environment

NASA Technical Reports Server (NTRS)

Gotsis, Pascal K.; Guptill, James D.

1995-01-01

Results are presented of parametric studies to assess the effects of various parameters on the free vibration behavior (natural frequencies) of (plus or minus theta)2, angle-ply fiber composite thin shells in a hot environment. These results were obtained by using a three-dimensional finite element structural analysis computer code. The fiber composite shell is assumed to be cylindrical and made from T-300 graphite fibers embedded in an intermediate-modulus high-strength matrix (IMHS). The residual stresses induced into the laminated structure during curing are taken into account. The following parameters are investigated: the length and the thickness of the shell, the fiber orientations, the fiber volume fraction, the temperature profile through the thickness of the laminate and the different ply thicknesses. Results obtained indicate that: the fiber orientations and the length of the laminated shell had significant effect on the natural frequencies. The fiber volume fraction, the laminate thickness and the temperature profile through the shell thickness had a weak effect on the natural frequencies. Finally, the laminates with different ply thicknesses had insignificant influence on the behavior of the vibrated laminated shell.

In-vitro Assessment of Knee MRI in the Presence of Metal Implants Comparing MAVRIC-SL and Conventional FSE Sequences at 1.5 and 3 Tesla Field Strength

PubMed Central

Liebl, Hans; Heilmeier, Ursula; Lee, Sonia; Nardo, Lorenzo; Patsch, Janina; Schuppert, Christopher; Han, Misung; Rondak, Ina-Christine; Banerjee, Suchandrima; Koch, Kevin; Link, Thomas M.; Krug, Roland

2014-01-01

PURPOSE To assess lesion detection and artifact size reduction of a MAVRIC-SEMAC hybrid sequence (MAVRIC-SL) compared to standard sequences at 1.5T and 3T in porcine knee specimens with metal hardware. METHODS Artificial cartilage and bone lesions of defined size were created in the proximity of titanium and steel screws with 2.5 mm diameter in 12 porcine knee specimens and were imaged at 1.5T and 3T MRI with MAVRIC-SL PD and STIR, standard FSE T2 PD and STIR and fat-saturated T2 FSE sequences. Three radiologists blinded to the lesion locations assessed lesion detection rates on randomized images for each sequence using ROC. Artifact length and width were measured. RESULTS Metal artifact sizes were largest in the presence of steel screws at 3T (FSE T2 FS: 28.7cm2) and 1.5T (16.03cm2). MAVRIC-SL PD and STIR reduced artifact sizes at both 3T (1.43cm2; 2.46cm2) and 1.5T (1.16cm2; 1.59cm2) compared to FS T2 FSE sequences (27.57cm2; 13.20cm2). At 3T, ROC derived AUC values using MAVRIC-SL sequences were significantly higher compared to standard sequences (MAVRIC-PD: 0.87, versus FSE-T2-FS: 0.73 (p=0.025); MAVRIC- STIR: 0.9 versus T2-STIR: 0.78 (p=0.001) and versus FSE-T2-FS: 0.73 (p=0.026)). Similar values were observed at 1.5T. Comparison of 3T and 1.5T showed no significant differences (MAVRIC-SL PD: p=0.382; MAVRIC-SL STIR: p=0.071. CONCLUSION MAVRIC-SL sequences provided superior lesion detection and reduced metal artifact size at both 1.5T and 3T compared to conventionally used FSE sequences. No significant disadvantage was found comparing MAVRIC-SL at 3T and 1.5T, though metal artifacts at 3T were larger. PMID:24912802

Refined hierarchical kinematics quasi-3D Ritz models for free vibration analysis of doubly curved FGM shells and sandwich shells with FGM core

NASA Astrophysics Data System (ADS)

Fazzolari, Fiorenzo A.; Carrera, Erasmo

2014-02-01

In this paper, the Ritz minimum energy method, based on the use of the Principle of Virtual Displacements (PVD), is combined with refined Equivalent Single Layer (ESL) and Zig Zag (ZZ) shell models hierarchically generated by exploiting the use of Carrera's Unified Formulation (CUF), in order to engender the Hierarchical Trigonometric Ritz Formulation (HTRF). The HTRF is then employed to carry out the free vibration analysis of doubly curved shallow and deep functionally graded material (FGM) shells. The PVD is further used in conjunction with the Gauss theorem to derive the governing differential equations and related natural boundary conditions. Donnell-Mushtari's shallow shell-type equations are given as a particular case. Doubly curved FGM shells and doubly curved sandwich shells made up of isotropic face sheets and FGM core are investigated. The proposed shell models are widely assessed by comparison with the literature results. Two benchmarks are provided and the effects of significant parameters such as stacking sequence, boundary conditions, length-to-thickness ratio, radius-to-length ratio and volume fraction index on the circular frequency parameters and modal displacements are discussed.

Increasing rice plant growth by Trichoderma sp.

NASA Astrophysics Data System (ADS)

Doni, Febri; Isahak, Anizan; Zain, Che Radziah Che Mohd; Sulaiman, Norela; Fathurahman, F.; Zain, Wan Nur Syazana Wan Mohd.; Kadhimi, Ahsan A.; Alhasnawi, Arshad Naji; Anhar, Azwir; Yusoff, Wan Mohtar Wan

2016-11-01

Trichoderma sp. is a plant growth promoting fungi in many crops. Initial observation on the ability to enhance rice germination and vigor have been reported. In this study, the effectiveness of a local isolate Trichoderma asprellum SL2 to enhance rice seedling growth was assessed experimentally under greenhouse condition using a completely randomized design. Results showed that inoculation of rice plants with Trichoderma asprellum SL2 significantly increase rice plants height, root length, wet weight, leaf number and biomass compared to untreated rice plants (control). The result of this study can serve as a reference for further work on the application of beneficial microorganisms to enhance rice production.

Nonlinear force-length relationship in the ADP-induced contraction of skeletal myofibrils.

PubMed

Shimamoto, Yuta; Kono, Fumiaki; Suzuki, Madoka; Ishiwata, Shin'ichi

2007-12-15

The regulatory mechanism of sarcomeric activity has not been fully clarified yet because of its complex and cooperative nature, which involves both Ca(2+) and cross-bridge binding to the thin filament. To reveal the mechanism of regulation mediated by the cross-bridges, separately from the effect of Ca(2+), we investigated the force-sarcomere length (SL) relationship in rabbit skeletal myofibrils (a single myofibril or a thin bundle) at SL > 2.2 microm in the absence of Ca(2+) at various levels of activation by exogenous MgADP (4-20 mM) in the presence of 1 mM MgATP. The individual SLs were measured by phase-contrast microscopy to confirm the homogeneity of the striation pattern of sarcomeres during activation. We found that at partial activation with 4-8 mM MgADP, the developed force nonlinearly depended on the length of overlap between the thick and the thin filaments; that is, contrary to the maximal activation, the maximal active force was generated at shorter overlap. Besides, the active force became larger, whereas this nonlinearity tended to weaken, with either an increase in [MgADP] or the lateral osmotic compression of the myofilament lattice induced by the addition of a macromolecular compound, dextran T-500. The model analysis, which takes into account the [MgADP]- and the lattice-spacing-dependent probability of cross-bridge formation, was successfully applied to account for the force-SL relationship observed at partial activation. These results strongly suggest that the cross-bridge works as a cooperative activator, the function of which is highly sensitive to as little as

Coordination and propulsion and non-propulsion phases in 100 meter breaststroke swimming.

PubMed

Strzała, Marek; Krężałek, Piotr; Kucia-Czyszczoń, Katarzyna; Ostrowski, Andrzej; Stanula, Arkadiusz; Tyka, Anna K; Sagalara, Andrzej

2014-01-01

The main purpose of this study was to analyze the coordination, propulsion and non-propulsion phases in the 100 meter breaststroke race. Twenty-seven male swimmers (15.7 ± 1.98 years old) with the total body length (TBL) of 247.0 ± 10.60 [cm] performed an all-out 100 m breaststroke bout. The bouts were recorded with an underwater camera installed on a portable trolley. The swimming kinematic parameters, stroke rate (SR) and stroke length (SL), as well as the coordination indices based on propulsive or non-propulsive movement phases of the arms and legs were distinguished. Swimming speed (V100surface breast) was associated with SL (R = 0.41, p < 0.05) and with TBL tending towards statistical significance (R = 0.36, p < 0.07), all relationships between the selected variables in the study were measured using partial correlations with controlled age. SL interplayed negatively with the limbs propulsive phase Overlap indicator (R = -0.46, p < 0.05), but had no significant relationship to the non-propulsion Glide indicator. The propulsion in-sweep (AP3) phase of arms and their non-propulsion partial air recovery (ARair) phase interplayed with V100surface breast (R = 0.51, p < 0.05 and 0.48 p < 0.05) respectively, displaying the importance of proper execution of this phase (AP3) and in reducing the resistance recovery phases in consecutive ones.

Quantum efficiency investigations of type-II InAs/GaSb midwave infrared superlattice photodetectors

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

Giard, E., E-mail: edouard.giard@onera.fr; Ribet-Mohamed, I.; Jaeck, J.

2014-07-28

We present in this paper a comparison between different type-II InAs/GaSb superlattice (T2SL) photodiodes and focal plane array (FPA) in the mid-wavelength infrared domain to understand which phenomenon drives the performances of the T2SL structure in terms of quantum efficiency (QE). Our measurements on test photodiodes suggest low minority carrier diffusion length in the “InAs-rich” design, which penalizes carriers' collection in this structure for low bias voltage and front side illumination. This analysis is completed by a comparison of the experimental data with a fully analytic model, which allows to infer a hole diffusion length shorter than 100 nm. In addition,more » measurements on a FPA with backside illumination are finally presented. Results show an average QE in the 3–4.7 μm window equal to 42% for U{sub bias} = −0.1 V, 77 K operating temperature and no anti-reflection coating. These measurements, completed by modulation transfer function and noise measurements, reveal that the InAs-rich design, despite a low hole diffusion length, is promising for high performance infrared imaging applications.« less

Novel evaporator architecture with entrance-length crossflow-paths for supercritical Organic Rankine Cycles

DOE PAGES

Sabau, Adrian S.; Nejad, Ali H.; Klett, James W.; ...

2017-11-26

Here in this article, a novel geometry is proposed for evaporators that are used in Supercritical Organic Rankine Cycles. The proposed geometry consists of successive plenums at several length-scale levels, creating a multi-scale heat exchanger (HX). The channels at the lowest length-scale levels were considered to have their length determined by the thermal entrance-length. Numerical simulations based on turbulent flow correlations for supercritical R134a and water were used to evaluate the performance of heat exchangers. Using the data on pumping power and area of heat exchange, the total present cost was evaluated using a cost model for shell-and-tube heat exchangers.more » With respect to the shell-and-tube baseline case, the cost per heat load and total costs of new HXs is lowered by approximately 20–26% and 15–30%, respectively. This reduction in present costs of the new HXs were found to be attributed to higher operational costs for the shell-and-tube HXs, as evidenced by the higher pumping power, as well their capital investment costs. The cost savings in the new HX designs compared to those of the shell-and-tube HXs, at similar heat load performance, indicate that the new HX architectures proposed in this paper are valid alternatives to traditional HX designs.« less

Computerized Buckling Analysis of Shells

DTIC Science & Technology

1981-06-01

principal elements of Koiter’s theory are outlined in the previous section. In his doctoral thesis published in 񓞹, Koiter shows that if certain...early 1960’s because the thesis was written in LM.. nJAl...t _CLrU1 6t AL. &Lý.A. >SL.2 LCL ._L L) . C r ~ n i: Ltia E;ULA.L ALb a 1JC~c&L~ cib atZ L...W. T., "Ovei de stabiliteit van het elastisch evenwicht," Delft thesis , H. J. Paris, Amsterdam; (English transl.) National - Aeronautics and Space

Conformal structure of massless scalar amplitudes beyond tree level

NASA Astrophysics Data System (ADS)

Banerjee, Nabamita; Banerjee, Shamik; Bhatkar, Sayali Atul; Jain, Sachin

2018-04-01

We show that the one-loop on-shell four-point scattering amplitude of massless ϕ 4 scalar field theory in 4D Minkowski space time, when Mellin transformed to the Celestial sphere at infinity, transforms covariantly under the global conformal group (SL(2, ℂ)) on the sphere. The unitarity of the four-point scalar amplitudes is recast into this Mellin basis. We show that the same conformal structure also appears for the two-loop Mellin amplitude. Finally we comment on some universal structure for all loop four-point Mellin amplitudes specific to this theory.

Do sarcomere length, collagen content, pH, intramuscular fat and desmin degradation explain variation in the tenderness of three ovine muscles?

PubMed

Starkey, Colin P; Geesink, Geert H; Collins, Damian; Hutton Oddy, V; Hopkins, David L

2016-03-01

The longissimus (n=118) (LL), semimembranosus (n=104) (SM) and biceps femoris (n=134) (BF) muscles were collected from lamb and sheep carcases and aged for 5days (LL and SM) and 14days (BF) to study the impact of muscle characteristics on tenderness as assessed by shear force (SF) and sensory evaluation. The impact of gender, animal age, collagen content, sarcomere length (SL), desmin degradation, ultimate pH and intramuscular fat (IMF) on tenderness was examined. The main factors which influenced SF of the LL were IMF, SL and desmin degradation, but for sensory tenderness, IMF, ultimate pH and gender were the main factors. The SF and sensory tenderness of the SM was best predicted by the degree of desmin degradation. For the BF soluble collagen and animal age both influenced SF. Different factors affect tenderness across muscles and not one prediction model applied across all muscles equally well. Copyright © 2015 Elsevier Ltd. All rights reserved.

High Density Linkage Map Construction and QTL Detection for Three Silique-Related Traits in Orychophragmus violaceus Derived Brassica napus Population.

PubMed

Yang, Yi; Shen, Yusen; Li, Shunda; Ge, Xianhong; Li, Zaiyun

2017-01-01

Seeds per silique (SS), seed weight (SW), and silique length (SL) are important determinant traits of seed yield potential in rapeseed ( Brassica napus L.), and are controlled by naturally occurring quantitative trait loci (QTLs). Mapping QTLs to narrow chromosomal regions provides an effective means of characterizing the genetic basis of these complex traits. Orychophragmus violaceus is a crucifer with long siliques, many SS, and heavy seeds. A novel B. napus introgression line with many SS was previously selected from multiple crosses ( B. rapa ssp. chinesis × O. violaceus ) × B. napus . In present study, a doubled haploid (DH) population with 167 lines was established from a cross between the introgression line and a line with far fewer SS, in order to detect QTLs for silique-related traits. By screening with a Brassica 60K single nucleotide polymorphism (SNP) array, a high-density linkage map consisting of 1,153 bins and spanning a cumulative length of 2,209.1 cM was constructed, using 12,602 high-quality polymorphic SNPs in the DH population. The average recombination bin densities of the A and C subgenomes were 1.7 and 2.4 cM, respectively. 45 QTLs were identified for the three traits in all, which explained 4.0-34.4% of the total phenotypic variation; 20 of them were integrated into three unique QTLs by meta-analysis. These unique QTLs revealed a significant positive correlation between SS and SL and a significant negative correlation between SW and SS, and were mapped onto the linkage groups A05, C08, and C09. A trait-by-trait meta-analysis revealed eight, four, and seven consensus QTLs for SS, SW, and SL, respectively, and five major QTLs ( cqSS.A09b, cqSS.C09, cqSW.A05, cqSW.C09 , and cqSL.C09 ) were identified. Five, three, and four QTLs for SS, SW, and SL, respectively, might be novel QTLs because of the existence of alien genetic loci for these traits in the alien introgression. Thirty-eight candidate genes underlying nine QTLs for silique-related traits were identified.

Small-Angle Neutron Scattering Studies of Magnetic Correlation Lengths in Nanoparticle Assemblies

NASA Astrophysics Data System (ADS)

Majetich, Sara

2009-03-01

Small-angle neutron scattering (SANS) measurements of ordered arrays of surfactant-coated magnetic nanoparticle reveal characteristic length scales associated with interparticle and intraparticle magnetic ordering. The high degree of uniformity in the monodisperse nanoparticle size and spacing leads to a pronounced diffraction peak and allows for a straightforward determination of these length scales [1]. There are notable differences in these length scales depending on the particle moment, which depends on the material (Fe, Co, Fe3O4) and diameter, and also on whether the metal particle core is surrounded by an oxide shell. For 8.5 nm particles containing an Fe core and thick Fe3O4 shell, evidence of a spin flop phase is seen in the magnetite shell when a field is applied , but not when the shell thickness is ˜0.5 nm [2]. 8.0 nm particles with an e-Co core and 0.75 nm CoO shell show no exchange bias effects while similar particles with a 2 nm thick shell so significant training effects below 90 K. Polarized SANS studied of 7 nm Fe3O4 nanoparticle assemblies show the ability to resolve the magnetization components in 3D. [4pt] [1] M. Sachan, C. Bonnoit, S. A. Majetich, Y. Ijiri, P. O. Mensah-Bonsu, J. A. Borchers, and J. J. Rhyne, Appl. Phys. Lett. 92, 152503 (2008). [0pt] [2] Yumi Ijiri, Christopher V. Kelly, Julie A. Borchers, James J. Rhyne, Dorothy F. Farrell, Sara A. Majetich, Appl. Phys. Lett. 86, 243102-243104 (2005). [0pt] [3] K. L. Krycka, R. Booth, J. A. Borchers, W. C. Chen, C. Conlon, T. Gentile, C. Hogg, Y. Ijiri, M. Laver, B. B. Maranville, S. A. Majetich, J. Rhyne, and S. M. Watson, Physica B (submitted).

Comprehensive Utilization of Biomass Process Residues Rich in Cellulose

NASA Astrophysics Data System (ADS)

Zhong, Mei; Li, Qiang; Yu, Jian; Dong, Li; Wang, Yin; Xu, Guangwen

2010-11-01

This article investigated the method preparing porous material (PM) with VL and SL. Applications of the prepared material was tested in removal aqueous phenol and COD in tarry water and as the catalyst support for selective catalytic reduction (SCR) of NO in flue gas. The results showed that the optimal activation condition in CO2 for the carbonized VL at 800° C was at 875° C for 1 h, which provided large BET surface area and micropore volume. This material exhibited the highest adsorption to aqueous phenol among all the tested materials including a commercial activated carbon made from coconut shell, showing the potential application of the VL-base porous material in wastewater treatment. The study demonstrated also that the vanadium-base selective catalytic reduction (SCR) catalyst supported on the VL-base porous material (V2O5/VL-PM) provided fairly good activity as well SO2 resistance at temperatures round 200° C for SCR of NO. The activation of the carbonized SL material in H2O was better than that in CO2 for developing the pore structure of the porous material. Steam can improve the formation of mesopore than CO2. This was confirmed by the conclusion that higher COD removal rate was occurred on the PM-1 from SL when H2O was used as an activator.

Sclerochronological analysis of Saxidomus gigantea: Implications for reconstructing past seasonality and sea ice extent in the Northern Pacific Ocean

NASA Astrophysics Data System (ADS)

Bassett, C.; Andrus, C. F. T.

2015-12-01

Sclerochronological analysis of biogenic carbonates provides valuable paleoenvironmental information. Oxygen isotope analysis of bivalve shell yields information on the temperature of the water in which the organism grew. However, in coastal environments, variations in δ18Owater may complicate the interpretation of shell isotope profiles. Measuring and comparing the length of seasonal shell growth in select species of bivalves may complement isotopic analysis, together providing a more precise paleoclimate reconstruction. This project aims to determine the reliability of sclerochronological analysis of bivalves in reconstructing seasonality along the Northwest Coast of North America. To compare bivalves growing at different seasonal temperature conditions, samples of Saxidomus gigantea were collected from southern Alaska and northern British Columbia. Winter cessation lines were identified using oxygen isotope (δ18O) peaks from a profile of variation over the life of the clam, which was sampled sequentially from a section of its shell. Shell growth stops below ~4-5°C and so each winter cessation indicates temperatures lower than this threshold. Lunar-daily growth lines were counted between these winter growth cessation breaks, which quantitatively measure the length of the growing season. The resulting data were compared between habitats to assess if this is a useful method of determining the length of the growing season. If this method of assessing seasonality appears valid, it can be applied to ancient shells abundant in archaeological shell middens to make inferences about past seawater conditions and potentially indicate the presence or absence of the conditions necessary for sea ice accumulation.

Analysis of flexible layered shallow shells on elastic foundation

NASA Astrophysics Data System (ADS)

Stupishin, L.; Kolesnikov, A.; Tolmacheva, T.

2017-05-01

This paper contains numerical analysis of a layered geometric nonlinear flexible shallow shell based on an elastic foundation. Rise of arch in the center of the shell, width, length and type of support are given. The design variable is taken to be the thickness of the shallow shell, the form of the middle surface forming and the characteristic of elastic foundations. Critical force coefficient and stress of shells are calculated by Bubnov-Galerkin. Stress, characteristic of elastic foundations - thickness dependence are presented.

Self consistent field theory of virus assembly

NASA Astrophysics Data System (ADS)

Li, Siyu; Orland, Henri; Zandi, Roya

2018-04-01

The ground state dominance approximation (GSDA) has been extensively used to study the assembly of viral shells. In this work we employ the self-consistent field theory (SCFT) to investigate the adsorption of RNA onto positively charged spherical viral shells and examine the conditions when GSDA does not apply and SCFT has to be used to obtain a reliable solution. We find that there are two regimes in which GSDA does work. First, when the genomic RNA length is long enough compared to the capsid radius, and second, when the interaction between the genome and capsid is so strong that the genome is basically localized next to the wall. We find that for the case in which RNA is more or less distributed uniformly in the shell, regardless of the length of RNA, GSDA is not a good approximation. We observe that as the polymer-shell interaction becomes stronger, the energy gap between the ground state and first excited state increases and thus GSDA becomes a better approximation. We also present our results corresponding to the genome persistence length obtained through the tangent-tangent correlation length and show that it is zero in case of GSDA but is equal to the inverse of the energy gap when using SCFT.

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

Sabau, Adrian S.; Nejad, Ali H.; Klett, James W.

Here in this article, a novel geometry is proposed for evaporators that are used in Supercritical Organic Rankine Cycles. The proposed geometry consists of successive plenums at several length-scale levels, creating a multi-scale heat exchanger (HX). The channels at the lowest length-scale levels were considered to have their length determined by the thermal entrance-length. Numerical simulations based on turbulent flow correlations for supercritical R134a and water were used to evaluate the performance of heat exchangers. Using the data on pumping power and area of heat exchange, the total present cost was evaluated using a cost model for shell-and-tube heat exchangers.more » With respect to the shell-and-tube baseline case, the cost per heat load and total costs of new HXs is lowered by approximately 20–26% and 15–30%, respectively. This reduction in present costs of the new HXs were found to be attributed to higher operational costs for the shell-and-tube HXs, as evidenced by the higher pumping power, as well their capital investment costs. The cost savings in the new HX designs compared to those of the shell-and-tube HXs, at similar heat load performance, indicate that the new HX architectures proposed in this paper are valid alternatives to traditional HX designs.« less

Net Force of an Ideal Conductor on an Element of a Line of Charge Moving With Extreme Relativistic Speed

ERIC Educational Resources Information Center

Cawley, Robert

1978-01-01

Considers the problem of determining the force on an element of a finite length line of charge moving horizontally with extreme relativistic speed through an evacuated space above an infinite plane ideal conducting surface. (SL)

Dynamics and control of tethered antennas/reflectors in orbit

NASA Astrophysics Data System (ADS)

Liu, Liangdong; Bainum, Peter M.

The system linear equations for the motion of a tethered shallow spherical shell in orbit with its symmetry axis nominally following the local vertical are developed. The shell roll, yaw, tether out-of-plane swing motion and elastic vibrations are decoupled from the shell and tether in-plane pitch motions and elastic vibrations. The neutral gravity stability conditions for the special case of a constant length rigid tether are given for in-plane motion and out-of-plant motion. It is proved that the in-plane motion of the system could be asymptotically stable based on Rupp's tension control law, for a variable length tether. However, the system simulation results indicate that the transient responses can be improved significantly, especially for the damping of the tether and shell pitch motion, by an optimal feedback control law for the rigid variable length tether model. It is also seen that the system could be unstable when the effect of tether flexibility is included if the control gains are not chosen carefully. The transient responses for three different tension control laws are compared during typical station keeping operations.

Description of Hydration Water in Protein (Green Fluorescent Protein) Solution

DOE PAGES

Perticaroli, Stefania; Ehlers, Georg; Stanley, Christopher B.; ...

2016-10-26

The structurally and dynamically perturbed hydration shells that surround proteins and biomolecules have a substantial influence upon their function and stability. This makes the extent and degree of water perturbation of practical interest for general biological study and industrial formulation. Here, we present an experimental description of the dynamical perturbation of hydration water around green fluorescent protein in solution. Less than two shells (~5.5 Å) were perturbed, with dynamics a factor of 2–10 times slower than bulk water, depending on their distance from the protein surface and the probe length of the measurement. Furthermore, this dependence on probe length demonstratesmore » that hydration water undergoes subdiffusive motions (τ ∝ q –2.5 for the first hydration shell, τ ∝ q –2.3 for perturbed water in the second shell), an important difference with neat water, which demonstrates diffusive behavior (τ ∝ q –2). Our results help clarify the seemingly conflicting range of values reported for hydration water retardation as a logical consequence of the different length scales probed by the analytical techniques used.« less

The pea TCP transcription factor PsBRC1 acts downstream of Strigolactones to control shoot branching.

PubMed

Braun, Nils; de Saint Germain, Alexandre; Pillot, Jean-Paul; Boutet-Mercey, Stéphanie; Dalmais, Marion; Antoniadi, Ioanna; Li, Xin; Maia-Grondard, Alessandra; Le Signor, Christine; Bouteiller, Nathalie; Luo, Da; Bendahmane, Abdelhafid; Turnbull, Colin; Rameau, Catherine

2012-01-01

The function of PsBRC1, the pea (Pisum sativum) homolog of the maize (Zea mays) TEOSINTE BRANCHED1 and the Arabidopsis (Arabidopsis thaliana) BRANCHED1 (AtBRC1) genes, was investigated. The pea Psbrc1 mutant displays an increased shoot-branching phenotype, is able to synthesize strigolactone (SL), and does not respond to SL application. The level of pleiotropy of the SL-deficient ramosus1 (rms1) mutant is higher than in the Psbrc1 mutant, rms1 exhibiting a relatively dwarf phenotype and more extensive branching at upper nodes. The PsBRC1 gene is mostly expressed in the axillary bud and is transcriptionally up-regulated by direct application of the synthetic SL GR24 and down-regulated by the cytokinin (CK) 6-benzylaminopurine. The results suggest that PsBRC1 may have a role in integrating SL and CK signals and that SLs act directly within the bud to regulate its outgrowth. However, the Psbrc1 mutant responds to 6-benzylaminopurine application and decapitation by increasing axillary bud length, implicating a PsBRC1-independent component of the CK response in sustained bud growth. In contrast to other SL-related mutants, the Psbrc1 mutation does not cause a decrease in the CK zeatin riboside in the xylem sap or a strong increase in RMS1 transcript levels, suggesting that the RMS2-dependent feedback is not activated in this mutant. Surprisingly, the double rms1 Psbrc1 mutant displays a strong increase in numbers of branches at cotyledonary nodes, whereas branching at upper nodes is not significantly higher than the branching in rms1. This phenotype indicates a localized regulation of branching at these nodes specific to pea.

Simple models of SL-9 impact plumes in flight

NASA Astrophysics Data System (ADS)

Harrington, J.; Deming, D.

1998-09-01

We have extended our ballistic Monte-Carlo model of the Shoemaker-Levy 9 impact plumes (J. Harrington and D. Deming 1996. Simple models of SL9 impact plumes, Bull. Am. Astron. Soc. 28 1150--1151) to calculate the appearance of the plumes in flight. We compare these synthetic images to the data taken by the Hubble Space Telescope of plumes on the limb of Jupiter during impacts A, E, G, and W. The model uses a parameterized version of the final power-law velocity distribution from the impact models of Zahnle and Mac Low. The observed plume heights, lightcurve features, and debris patterns fix the values of model parameters. The parameters that best reproduce the debris patterns dictate an approximately conic plume geometry, with the apex of the cone initially near the impact site, the cone's axis pointed in the direction from which the impactor came, and an opening angle >45sp ° from the axis. Since material of a given velocity is, at any given time, a certain distance from the cone apex, the geometry spreads high-velocity material much thinner than low-velocity material. The power law exponent of -1.55 combines with this effect to make mass density fall off as the -3.55 power of the velocity (or distance from the plume base). However, the outer shell of highest-velocity material, corresponding to the atmospheric shock wave, carries considerably elevated mass density. We are currently studying the range of reasonable optical properties to determine whether the visible plume tops corresponded to the physical top of this shell, or to a lower density contour.

Time-varying impedance of the human ankle in the sagittal and frontal planes during straight walk and turning steps.

PubMed

Ficanha, Evandro M; Ribeiro, Guilherme A; Knop, Lauren; Rastgaar, Mo

2017-07-01

This paper describes the methods and experiment protocols for estimation of the human ankle impedance during turning and straight line walking. The ankle impedance of two human subjects during the stance phase of walking in both dorsiflexion plantarflexion (DP) and inversion eversion (IE) were estimated. The impedance was estimated about 8 axes of rotations of the human ankle combining different amounts of DP and IE rotations, and differentiating among positive and negative rotations at 5 instants of the stance length (SL). Specifically, the impedance was estimated at 10%, 30%, 50%, 70% and 90% of the SL. The ankle impedance showed great variability across time, and across the axes of rotation, with consistent larger stiffness and damping in DP than IE. When comparing straight walking and turning, the main differences were in damping at 50%, 70%, and 90% of the SL with an increase in damping at all axes of rotation during turning.

Effects of low pH stress on shell traits and proteomes of the dove snail, Anachis misera inhabiting shallow vent environments off Kueishan Islet, Taiwan

NASA Astrophysics Data System (ADS)

Chen, Y. J.; Wu, J. Y.; Chen, C. T. A.; Liu, L. L.

2014-12-01

The effects of naturally acidified seawater on a snail species, Anachis misera (Family: Columbellidae) were quantified in five shallow vent-based environments off Kueishan Islet, Taiwan. An absence of Anachis snails was observed in the most acidic North site (pH 7.22), and the size structure differed among the remaining East, South, Southwest and Northwest sites. If a positive correlation between shell length and shell width or total weight existed, the coefficient of determination (R2) of the equations was low, i.e., 0.207-0.444. Snails from the Northwest site (pH 7.33) exhibited a more globular shape than those of the South ones (pH 7.80). Standardized shell thickness T1 (thickness of body whorl : shell length) and T2 (thickness of penultimate whorl : shell length) from the Northwest site showed a decrease of 6.3 and 9.4%, respectively, compared to the South ones. In a similar vein, based on the 16 examined protein spots, protein expression profiles of snails in the South were distinct. With further characterization by principle component analysis, the separation was mainly contributed by the first (i.e., spots 8, 1, 15, and 12) and second (i.e., spots 15, 13, 12, 1, and 11) principal-components. As a whole, the shallow vent-based findings provide new information from subtropics on the effects of ocean acidification on gastropod snails in natural environments.

Weathering Tests on Protective Helmets Approved to Australian Standard AS 1698 (for Vehicle Users).

DTIC Science & Technology

1979-11-01

Expanded Polystyrene HELMETI Colour Production; SAA Size ,Length Width j Mass Circumference Date Serial No. cm imm mm nu qm nun L A White July 󈨒 B535336...HELMET DETAILS Make: ARAI Model: S-75 Shell: Fibreglass Reinforced Polyester Resin Liner: Expanded Polystyrene HELMET Colour Production SAA Size...Reinforced Polyester Resin Liner; Expanded Polystyrene (with thin plastic inner shell) HELMET Colour Production’ SAA Size Length Width Mass

Multifactor analysis and simulation of the surface runoff and soil infiltration at different slope gradients

NASA Astrophysics Data System (ADS)

Huang, J.; Kang, Q.; Yang, J. X.; Jin, P. W.

2017-08-01

The surface runoff and soil infiltration exert significant influence on soil erosion. The effects of slope gradient/length (SG/SL), individual rainfall amount/intensity (IRA/IRI), vegetation cover (VC) and antecedent soil moisture (ASM) on the runoff depth (RD) and soil infiltration (INF) were evaluated in a series of natural rainfall experiments in the South of China. RD is found to correlate positively with IRA, IRI, and ASM factors and negatively with SG and VC. RD decreased followed by its increase with SG and ASM, it increased with a further decrease with SL, exhibited a linear growth with IRA and IRI, and exponential drop with VC. Meanwhile, INF exhibits a positive correlation with SL, IRA and IRI and VC, and a negative one with SG and ASM. INF was going up and then down with SG, linearly rising with SL, IRA and IRI, increasing by a logit function with VC, and linearly falling with ASM. The VC level above 60% can effectively lower the surface runoff and significantly enhance soil infiltration. Two RD and INF prediction models, accounting for the above six factors, were constructed using the multiple nonlinear regression method. The verification of those models disclosed a high Nash-Sutcliffe coefficient and low root-mean-square error, demonstrating good predictability of both models.

Evolutionary Association of Stomatal Traits with Leaf Vein Density in Paphiopedilum, Orchidaceae

PubMed Central

Sun, Mei; Zhang, Juan-Juan; Cao, Kun-Fang; Hu, Hong

2012-01-01

Background Both leaf attributes and stomatal traits are linked to water economy in land plants. However, it is unclear whether these two components are associated evolutionarily. Methodology/Principal Findings In characterizing the possible effect of phylogeny on leaf attributes and stomatal traits, we hypothesized that a correlated evolution exists between the two. Using a phylogenetic comparative method, we analyzed 14 leaf attributes and stomatal traits for 17 species in Paphiopedilum. Stomatal length (SL), stomatal area (SA), upper cuticular thickness (UCT), and total cuticular thickness (TCT) showed strong phylogenetic conservatism whereas stomatal density (SD) and stomatal index (SI) were significantly convergent. Leaf vein density was correlated with SL and SD whether or not phylogeny was considered. The lower epidermal thickness (LET) was correlated positively with SL, SA, and stomatal width but negatively with SD when phylogeny was not considered. When this phylogenetic influence was factored in, only the significant correlation between SL and LET remained. Conclusion/Significance Our results support the hypothesis for correlated evolution between stomatal traits and vein density in Paphiopedilum. However, they do not provide evidence for an evolutionary association between stomata and leaf thickness. These findings lend insight into the evolution of traits related to water economy for orchids under natural selection. PMID:22768224

A genome-wide association study of limb bone length using a Large White × Minzhu intercross population.

PubMed

Zhang, Long-Chao; Li, Na; Liu, Xin; Liang, Jing; Yan, Hua; Zhao, Ke-Bin; Pu, Lei; Shi, Hui-Bi; Zhang, Yue-Bo; Wang, Li-Gang; Wang, Li-Xian

2014-11-04

In pig, limb bone length influences ham yield and body height to a great extent and has important economic implications for pig industry. In this study, an intercross population was constructed between the indigenous Chinese Minzhu pig breed and the western commercial Large White pig breed to examine the genetic basis for variation in limb bone length. The aim of this study was to detect potential genetic variants associated with porcine limb bone length. A total of 571 F2 individuals from a Large White and Minzhu intercross population were genotyped using the Illumina PorcineSNP60K Beadchip, and phenotyped for femur length (FL), humerus length (HL), hipbone length (HIPL), scapula length (SL), tibia length (TL), and ulna length (UL). A genome-wide association study was performed by applying the previously reported approach of genome-wide rapid association using mixed model and regression. Statistical significance of the associations was based on Bonferroni-corrected P-values. A total of 39 significant SNPs were mapped to a 11.93 Mb long region on pig chromosome 7 (SSC7). Linkage analysis of these significant SNPs revealed three haplotype blocks of 495 kb, 376 kb and 492 kb, respectively, in the 11.93 Mb region. Annotation based on the pig reference genome identified 15 genes that were located near or contained the significant SNPs in these linkage disequilibrium intervals. Conditioned analysis revealed that four SNPs, one on SSC2 and three on SSC4, showed significant associations with SL and HL, respectively. Analysis of the 15 annotated genes that were identified in these three haplotype blocks indicated that HMGA1 and PPARD, which are expressed in limbs and influence chondrocyte cell growth and differentiation, could be considered as relevant biological candidates for limb bone length in pig, with potential applications in breeding programs. Our results may also be useful for the study of the mechanisms that underlie human limb length and body height.

Multiscale structure and damage tolerance of coconut shells.

PubMed

Gludovatz, B; Walsh, F; Zimmermann, E A; Naleway, S E; Ritchie, R O; Kruzic, J J

2017-12-01

We investigated the endocarp of the fruit of Cocos nucifera (i.e., the inner coconut shell), examining the structure across multiple length scales through advanced characterization techniques and in situ testing of mechanical properties. Like many biological materials, the coconut shell possesses a hierarchical structure with distinct features at different length scales that depend on orientation and age. Aged coconut was found to have a significantly stronger (ultimate tensile strength, UTS = 48.5MPa), stiffer (Young's modulus, E = 1.92GPa), and tougher (fracture resistance (R-curve) peak of K J = 3.2MPa m 1/2 ) endocarp than the younger fruit for loading in the latitudinal orientation. While the mechanical properties of coconut shell were observed to improve with age, they also become more anisotropic: the young coconut shell had the same strength (17MPa) and modulus (0.64GPa) values and similar R-curves for both longitudinal and latitudinal loading configurations, whereas the old coconut had 82% higher strength for loading in the latitudinal orientation, and >50% higher crack growth toughness for cracking on the latitudinal plane. Structural aspects affecting the mechanical properties across multiple length scales with aging were identified as improved load transfer to the cellulose crystalline nanostructure (identified by synchrotron x-ray diffraction) and sclerification of the endocarp, the latter of which included closing of the cell lumens and lignification of the cell walls. The structural changes gave a denser and mechanically superior micro and nanostructure to the old coconut shell. Additionally, the development of anisotropy was attributed to the formation of an anisotropic open channel structure throughout the shell of the old coconut that affected both crack initiation during uniaxial tensile tests and the toughening mechanisms of crack trapping and deflection during crack propagation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Genetic Mapping and QTL Analysis of Growth-Related Traits in Pinctada fucata Using Restriction-Site Associated DNA Sequencing

PubMed Central

Li, Yaoguo; He, Maoxian

2014-01-01

The pearl oyster, Pinctada fucata (P. fucata), is one of the marine bivalves that is predominantly cultured for pearl production. To obtain more genetic information for breeding purposes, we constructed a high-density linkage map of P. fucata and identified quantitative trait loci (QTL) for growth-related traits. One F1 family, which included the two parents, 48 largest progeny and 50 smallest progeny, was sampled to construct a linkage map using restriction site-associated DNA sequencing (RAD-Seq). With low coverage data, 1956.53 million clean reads and 86,342 candidate RAD loci were generated. A total of 1373 segregating SNPs were used to construct a sex-average linkage map. This spanned 1091.81 centimorgans (cM), with 14 linkage groups and an average marker interval of 1.41 cM. The genetic linkage map coverage, Coa, was 97.24%. Thirty-nine QTL-peak loci, for seven growth-related traits, were identified using the single-marker analysis, nonparametric mapping Kruskal-Wallis (KW) test. Parameters included three for shell height, six for shell length, five for shell width, four for hinge length, 11 for total weight, eight for soft tissue weight and two for shell weight. The QTL peak loci for shell height, shell length and shell weight were all located in linkage group 6. The genotype frequencies of most QTL peak loci showed significant differences between the large subpopulation and the small subpopulation (P<0.05). These results highlight the effectiveness of RAD-Seq as a tool for generation of QTL-targeted and genome-wide marker data in the non-model animal, P. fucata, and its possible utility in marker-assisted selection (MAS). PMID:25369421

A comparison of the effects of visual deprivation and regular body weight support treadmill training on improving over-ground walking of stroke patients: a multiple baseline single subject design.

PubMed

Kim, Jeong-Soo; Kang, Sun-Young; Jeon, Hye-Seon

2015-01-01

The body-weight-support treadmill (BWST) is commonly used for gait rehabilitation, but other forms of BWST are in development, such as visual-deprivation BWST (VDBWST). In this study, we compare the effect of VDBWST training and conventional BWST training on spatiotemporal gait parameters for three individuals who had hemiparetic strokes. We used a single-subject experimental design, alternating multiple baselines across the individuals. We recruited three individuals with hemiparesis from stroke; two on the left side and one on the right. For the main outcome measures we assessed spatiotemporal gait parameters using GAITRite, including: gait velocity; cadence; step time of the affected side (STA); step time of the non-affected side (STN); step length of the affected side (SLA); step length of the non-affected side (SLN); step-time asymmetry (ST-asymmetry); and step-length asymmetry (SL-asymmetry). Gait velocity, cadence, SLA, and SLN increased from baseline after both interventions, but STA, ST-asymmetry, and SL-asymmetry decreased from the baseline after the interventions. The VDBWST was significantly more effective than the BWST for increasing gait velocity and cadence and for decreasing ST-asymmetry. VDBWST is more effective than BWST for improving gait performance during the rehabilitation for ground walking.

The feasibility of bomb radiocarbon analysis to support an age-at-length relationship for red abalone, Haliotis rufescens Swainson in northern California

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

Leaf, R T; Andrews, A H; Cailliet, G M

2009-01-07

Analysis of bomb generated radiocarbon ({sup 14}C) changes in a red abalone, Haliotis rufescens Swainson shell was used to investigate age-at-length relationships derived from data from a previous multi-year, multi-site tag-recapture study. Shell carbonate was extracted from four successive growth trajectory locations in a single shell with a length of 251 mm MSL. Extraction locations were based on VBGF predictions and chosen to span the initial rise of the {sup 14}C-bomb pulse that is known to have occurred in surface ocean waters during 1958 {+-} 1 y in the northeast Pacific. The close temporal correspondence of the red abalone samplemore » series to regional {Delta}{sup 14}C records demonstrated the utility of the technique for validating age-at-length relationships for the red abalone. The findings provided support for a mean VBGF derived age of 32 y (range 30 to 33 y) for the specimen; however, the analysis of {sup 14}C data indicated that the specimen could be older.« less

VHSIC Hardware Description Language (VHDL) Benchmark Suite

DTIC Science & Technology

1990-10-01

T7 prit.iy label iTM Architecture label I flO inch Label I TIC ) P rae s Label I W Conkgurstion Spec. 1 21 Appendix B. Test Descriptions, Shell Code...Siensls R Accnss Operaist s Iov (soc 3 3 & 7 3 61 $ File I/0 S1 Reed S2 Write T Label Site TI Signal TIA Archi~ecture TIE Block TIC Port T2 VariableI...Access Operations I (sec 3 3 & 7.3 61 1 S FI I/0 1 Sl Read 52 Write T Label SreI TI Signal TIA Architeclt TIR Block TIC

Depressed Frank-Starling mechanism in the left ventricular muscle of the knock-in mouse model of dilated cardiomyopathy with troponin T deletion mutation ΔK210.

PubMed

Inoue, Takahiro; Kobirumaki-Shimozawa, Fuyu; Kagemoto, Tatsuya; Fujii, Teruyuki; Terui, Takako; Kusakari, Yoichiro; Hongo, Kenichi; Morimoto, Sachio; Ohtsuki, Iwao; Hashimoto, Kazuhiro; Fukuda, Norio

2013-10-01

It has been reported that the Frank-Starling mechanism is coordinately regulated in cardiac muscle via thin filament "on-off" equilibrium and titin-based lattice spacing changes. In the present study, we tested the hypothesis that the deletion mutation ΔK210 in the cardiac troponin T gene shifts the equilibrium toward the "off" state and accordingly attenuate the sarcomere length (SL) dependence of active force production, via reduced cross-bridge formation. Confocal imaging in isolated hearts revealed that the cardiomyocytes were enlarged, especially in the longitudinal direction, in ΔK210 hearts, with striation patterns similar to those in wild type (WT) hearts, suggesting that the number of sarcomeres is increased in cardiomyocytes but the sarcomere length remains unaltered. For analysis of the SL dependence of active force, skinned muscle preparations were obtained from the left ventricle of WT and knock-in (ΔK210) mice. An increase in SL from 1.90 to 2.20μm shifted the mid-point (pCa50) of the force-pCa curve leftward by ~0.21pCa units in WT preparations. In ΔK210 muscles, Ca(2+) sensitivity was lower by ~0.37pCa units, and the SL-dependent shift of pCa50, i.e., ΔpCa50, was less pronounced (~0.11pCa units), with and without protein kinase A treatment. The rate of active force redevelopment was lower in ΔK210 preparations than in WT preparations, showing blunted thin filament cooperative activation. An increase in thin filament cooperative activation upon an increase in the fraction of strongly bound cross-bridges by MgADP increased ΔpCa50 to ~0.21pCa units. The depressed Frank-Starling mechanism in ΔK210 hearts is the result of a reduction in thin filament cooperative activation. © 2013.

Synthesis of Various Metal/TiO2 Core/shell Nanorod Arrays

NASA Astrophysics Data System (ADS)

Zhu, Wei; Wang, Guan-zhong; Hong, Xun; Shen, Xiao-shuang

2011-02-01

We present a general approach to fabricate metal/TiO2 core/shell nanorod structures by two-step electrodeposition. Firstly, TiO2 nanotubes with uniform wall thickness are prepared in anodic aluminum oxide (AAO) membranes by electrodeposition. The wall thickness of the nanotubes could be easily controlled by modulating the deposition time, and their outer diameter and length are only limited by the channel diameter and the thickness of the AAO membranes, respectively. The nanotubes' tops prepared by this method are open, while the bottoms are connected directly with the Au film at the back of the AAO membranes. Secondly, Pd, Cu, and Fe elements are filled into the TiO2 nanotubes to form core/shell structures. The core/shell nanorods prepared by this two-step process are high density and free-standing, and their length is dependent on the deposition time.

Low energy electron attenuation lengths in core–shell nanoparticles

DOE PAGES

Jacobs, Michael I.; Kostko, Oleg; Ahmed, Musahid; ...

2017-05-05

Here, a velocity map imaging spectrometer is used to measure photoemission from free core–shell nanoparticles, where a salt core is coated with a liquid hydrocarbon shell (i.e. squalane). By varying the radial thickness of the hydrocarbon shell, electron attenuation lengths (EALs) are determined by measuring the decay in photoemission intensity from the salt core. In squalane, electrons with kinetic energy (KE) above 2 eV are found to have EALs of 3–5 nm, whereas electrons with smaller KE (<2 eV) have significantly larger EALs of >15 nm. These results (in the context of other energy-resolved EAL measurements) suggest that the energymore » dependent behavior of low energy electrons is similar in dielectrics when KE > 2 eV. At this energy the EALs do not appear to exhibit strong energy dependence. However, at very low KE (<2 eV), the EALs diverge and appear to be extremely material dependent.« less

Structural Evolution of Supercritical CO2 across the Frenkel Line.

PubMed

Bolmatov, Dima; Zav'yalov, D; Gao, M; Zhernenkov, Mikhail

2014-08-21

Here, we study structural properties of the supercritical carbon dioxide and discover the existence of persistent medium-range order correlations, which make supercritical carbon dioxide nonuniform and heterogeneous on an intermediate length scale. We report on the CO2 heterogeneity shell structure where, in the first shell, both carbon and oxygen atoms experience gas-like-type interactions with short-range order correlations while within the second shell, oxygen atoms essentially exhibit a liquid-like type of interactions due to localization of transverse-like phonon packets. Importantly, we highlight a catalytic role of atoms inside of the nearest-neighbor heterogeneity shell in providing a mechanism for diffusion and proving the existence of an additional thermodynamic boundary in the supercritical carbon dioxide on an intermediate length scale. Finally, we discuss important implications for answering the intriguing question whether Venus may have had CO2 oceans and urge for an experimental detection of this persistent local-order heterogeneity.

Disturbed resting state EEG synchronization in bipolar disorder: A graph-theoretic analysis☆

PubMed Central

Kim, Dae-Jin; Bolbecker, Amanda R.; Howell, Josselyn; Rass, Olga; Sporns, Olaf; Hetrick, William P.; Breier, Alan; O'Donnell, Brian F.

2013-01-01

Disruption of functional connectivity may be a key feature of bipolar disorder (BD) which reflects disturbances of synchronization and oscillations within brain networks. We investigated whether the resting electroencephalogram (EEG) in patients with BD showed altered synchronization or network properties. Resting-state EEG was recorded in 57 BD type-I patients and 87 healthy control subjects. Functional connectivity between pairs of EEG channels was measured using synchronization likelihood (SL) for 5 frequency bands (δ, θ, α, β, and γ). Graph-theoretic analysis was applied to SL over the electrode array to assess network properties. BD patients showed a decrease of mean synchronization in the alpha band, and the decreases were greatest in fronto-central and centro-parietal connections. In addition, the clustering coefficient and global efficiency were decreased in BD patients, whereas the characteristic path length increased. We also found that the normalized characteristic path length and small-worldness were significantly correlated with depression scores in BD patients. These results suggest that BD patients show impaired neural synchronization at rest and a disruption of resting-state functional connectivity. PMID:24179795

Investigation on the inertial cavitation threshold and shell properties of commercialized ultrasound contrast agent microbubbles.

PubMed

Guo, Xiasheng; Li, Qian; Zhang, Zhe; Zhang, Dong; Tu, Juan

2013-08-01

The inertial cavitation (IC) activity of ultrasound contrast agents (UCAs) plays an important role in the development and improvement of ultrasound diagnostic and therapeutic applications. However, various diagnostic and therapeutic applications have different requirements for IC characteristics. Here through IC dose quantifications based on passive cavitation detection, IC thresholds were measured for two commercialized UCAs, albumin-shelled KangRun(®) and lipid-shelled SonoVue(®) microbubbles, at varied UCA volume concentrations (viz., 0.125 and 0.25 vol. %) and acoustic pulse lengths (viz., 5, 10, 20, 50, and 100 cycles). Shell elastic and viscous coefficients of UCAs were estimated by fitting measured acoustic attenuation spectra with Sarkar's model. The influences of sonication condition (viz., acoustic pulse length) and UCA shell properties on IC threshold were discussed based on numerical simulations. Both experimental measurements and numerical simulations indicate that IC thresholds of UCAs decrease with increasing UCA volume concentration and acoustic pulse length. The shell interfacial tension and dilatational viscosity estimated for SonoVue (0.7 ± 0.11 N/m, 6.5 ± 1.01 × 10(-8) kg/s) are smaller than those of KangRun (1.05 ± 0.18 N/m, 1.66 ± 0.38 × 10(-7) kg/s); this might result in lower IC threshold for SonoVue. The current results will be helpful for selecting and utilizing commercialized UCAs for specific clinical applications, while minimizing undesired IC-induced bioeffects.

A simplified method of walking track analysis to assess short-term locomotor recovery after acute spinal cord injury caused by thoracolumbar intervertebral disc extrusion in dogs.

PubMed

Song, R B; Oldach, M S; Basso, D M; da Costa, R C; Fisher, L C; Mo, X; Moore, S A

2016-04-01

The purpose of this study was to evaluate a simplified method of walking track analysis to assess treatment outcome in canine spinal cord injury. Measurements of stride length (SL) and base of support (BS) were made using a 'finger painting' technique for footprint analysis in all limbs of 20 normal dogs and 27 dogs with 28 episodes of acute thoracolumbar spinal cord injury (SCI) caused by spontaneous intervertebral disc extrusion. Measurements were determined at three separate time points in normal dogs and on days 3, 10 and 30 following decompressive surgery in dogs with SCI. Values for SL, BS and coefficient of variance (COV) for each parameter were compared between groups at each time point. Mean SL was significantly shorter in all four limbs of SCI-affected dogs at days 3, 10, and 30 compared to normal dogs. SL gradually increased toward normal in the 30 days following surgery. As measured by this technique, the COV-SL was significantly higher in SCI-affected dogs than normal dogs in both thoracic limbs (TL) and pelvic limbs (PL) only at day 3 after surgery. BS-TL was significantly wider in SCI-affected dogs at days 3, 10 and 30 following surgery compared to normal dogs. These findings support the use of footprint parameters to compare locomotor differences between normal and SCI-affected dogs, and to assess recovery from SCI. Additionally, our results underscore important changes in TL locomotion in thoracolumbar SCI-affected dogs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Radiometric characterization of type-II InAs/GaSb superlattice (t2sl) midwave infrared photodetectors and focal plane arrays

NASA Astrophysics Data System (ADS)

Nghiem, Jean; Giard, E.; Delmas, M.; Rodriguez, J. B.; Christol, P.; Caes, M.; Martijn, H.; Costard, E.; Ribet-Mohamed, I.

2017-09-01

In recent years, Type-II InAs/GaSb superlattice (T2SL) has emerged as a new material technology suitable for high performance infrared (IR) detectors operating from Near InfraRed (NIR, 2-3μm) to Very Long Wavelength InfraRed (LWIR, λ > 15μm) wavelength domains. To compare their performances with well-established IR technologies such as MCT, InSb or QWIP cooled detectors, specific electrical and radiometric characterizations are needed: dark current, spectral response, quantum efficiency, temporal and spatial noises, stability… In this paper, we first present quantum efficiency measurements performed on T2SL MWIR (3-5μm) photodiodes and on one focal plane array (320x256 pixels with 30μm pitch, realized in the scope of a french collaboration ). Different T2SL structures (InAs-rich versus GaSb-rich) with the same cutoff wavelength (λc= 5μm at 80K) were studied. Results are analysed in term of carrier diffusion length in order to define the optimum thickness and type of doping of the absorbing zone. We then focus on the stability over time of a commercial T2SL FPA (320x256 pixels with 30μm pitch), measuring the commonly used residual fixed pattern noise (RFPN) figure of merit. Results are excellent, with a very stable behaviour over more than 3 weeks, and less than 10 flickering pixels, possibly giving access to long-term stability of IR absolute calibration.

Confocal Raman spectroscopy and AFM for evaluation of sidewalls in type II superlattice FPAs

NASA Astrophysics Data System (ADS)

Rotter, T. J.; Busani, T.; Rathi, P.; Jaeckel, F.; Reyes, P. A.; Malloy, K. J.; Ukhanov, A. A.; Plis, E.; Krishna, S.; Jaime-Vasquez, M.; Baril, N. F.; Benson, J. D.; Tenne, D. A.

2015-06-01

We propose to utilize confocal Raman spectroscopy combined with high resolution atomic force microscopy (AFM) for nondestructive characterisation of the sidewalls of etched and passivated small pixel (24 μm×24 μm) focal plane arrays (FPA) fabricated using LW/LWIR InAs/GaSb type-II strained layer superlattice (T2SL) detector material. Special high aspect ratio Si and GaAs AFM probes, with tip length of 13 μm and tip aperture less than 7°, allow characterisation of the sidewall morphology. Confocal microscopy enables imaging of the sidewall profile through optical sectioning. Raman spectra measured on etched T2SL FPA single pixels enable us to quantify the non-uniformity of the mesa delineation process.

Anisakidae in beluga whales Delphinapterus leucas from Hudson Bay and Hudson Strait.

PubMed

Najda, Katarzyna; Simard, Manon; Osewska, Julia; Dziekońska-Rynko, Janina; Dzido, Joanna; Rokicki, Jerzy

2015-06-29

A total of 190 nematodes was isolated from the stomachs of 13 beluga whales Delphinapterus leucas from the Arctic part of Hudson Bay and Hudson Strait. Infection intensity ranged from 1 to 57 specimens and prevalence was 84.62%. Morphological examination of the nematodes revealed the presence of 3 species: Pseudoterranova decipiens sensu lato, Contracaecum osculatum s.l., and Anisakis simplex s.l. Molecular analysis by PCR-based restriction fragment length polymorphism (PCR-RFLP) resulted in the identification of 4 species: Pseudoterranova bulbosa, Contracaecum osculatum A and C, and Anisakis simplex sensu stricto. The nematodes were present in 3 developmental stages: L3 (159 specimens), L4 (16 larvae), and adults (15 worms: 11 males and 4 females).

Species Profiles. Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (South Florida). Southern, Gulf, and Summer Flounders.

DTIC Science & Technology

1986-07-01

ridge of the head (Figure 11), the 46 days after hatching (at 8 to 11 body becomes increasingly compressed, m), and this process was completed and the...length (SL) or stages of summer flounder: (A) 12 h notochord length (tip of snout to after hatching, (B) 96 h after hatch- end of notochord ) (NL...at temperatures from 14.5 changes in osmoregulatory processes to 21.6 0C (58.1-70.90 F). Stokes that correspond to spawning (1977) found that

Laminated Thin Shell Structures Subjected to Free Vibration in a Hygrothermal Environment

NASA Technical Reports Server (NTRS)

Gotsis, Pascal K.; Guptill, James D.

1994-01-01

Parametric studies were performed to assess the effects of various parameters on the free-vibration behavior (natural frequencies) of (+/- theta)(sub 2) angle-ply, fiber composite, thin shell structures in a hygrothermal environment. Knowledge of the natural frequencies of structures is important in considering their response to various kinds of excitation, especially when structures and force systems are complex and when excitations are not periodic. The three dimensional, finite element structural analysis computer code CSTEM was used in the Cray YMP computer environment. The fiber composite shell was assumed to be cylindrical and made from T300 graphite fibers embedded in an intermediate-modulus, high-strength matrix. The following parameters were investigated: the length and the laminate thickness of the shell, the fiber orientation, the fiber volume fraction, the temperature profile through the thickness of the laminate, and laminates with different ply thicknesses. The results indicate that the fiber orientation and the length of the laminated shell had significant effects on the natural frequencies. The fiber volume fraction, the laminate thickness, and the temperature profile through the shell thickness had weak effects on the natural frequencies. Finally, the laminates with different ply thicknesses had an insignificant influence on the behavior of the vibrated laminated shell. Also, a single through-the-thickness, eight-node, three dimensional composite finite element analysis appears to be sufficient for investigating the free-vibration behavior of thin, composite, angle-ply shell structures.

Centrifugal Deposited Au-Pd Core-Shell Nanoparticle Film for Room-Temperature Optical Detection of Hydrogen Gas.

PubMed

Song, Han; Luo, Zhijie; Liu, Mingyao; Zhang, Gang; Peng, Wang; Wang, Boyi; Zhu, Yong

2018-05-06

In the present work, centrifugal deposited Au-Pd core-shell nanoparticle (NP) film was proposed for the room-temperature optical detection of hydrogen gas. The size dimension of 44, 48, 54, and 62 nm Au-Pd core-shell nanocubes with 40 nm Au core were synthesized following a solution-based seed-mediated growth method. Compared to a pure Pd NP, this core-shell structure with an inert Au core could decrease the H diffusion length in the Pd shell. Through a modified centrifugal deposition process, continues film samples with different core-shell NPs were deposited on 10 mm diameter quartz substrates. Under various hydrogen concentration conditions, the optical response properties of these samples were characterized by an intensity-based optical fiber bundle sensor. Experimental results show that the continues film that was composed of 62 nm Au-Pd core-shell NPs has achieved a stable and repeatable reflectance response with low zero drift in the range of 4 to 0.1% hydrogen after a stress relaxation mechanism at first few loading/unloading cycles. Because of the short H diffusion length due to the thinner Pd shell, the film sample composed of 44 nm Au-Pd NPs has achieved a dramatically decreased response/recovery time to 4 s/30 s. The experiments present the promising prospect of this simple method to fabricate optical hydrogen sensors with controllable high sensitivity and response rate at low cost.

Titin strain contributes to the Frank–Starling law of the heart by structural rearrangements of both thin- and thick-filament proteins

PubMed Central

Ait-Mou, Younss; Hsu, Karen; Farman, Gerrie P.; Kumar, Mohit; Greaser, Marion L.; Irving, Thomas C.; de Tombe, Pieter P.

2016-01-01

The Frank–Starling mechanism of the heart is due, in part, to modulation of myofilament Ca2+ sensitivity by sarcomere length (SL) [length-dependent activation (LDA)]. The molecular mechanism(s) that underlie LDA are unknown. Recent evidence has implicated the giant protein titin in this cellular process, possibly by positioning the myosin head closer to actin. To clarify the role of titin strain in LDA, we isolated myocardium from either WT or homozygous mutant (HM) rats that express a giant splice isoform of titin, and subjected the muscles to stretch from 2.0 to 2.4 μm of SL. Upon stretch, HM compared with WT muscles displayed reduced passive force, twitch force, and myofilament LDA. Time-resolved small-angle X-ray diffraction measurements of WT twitching muscles during diastole revealed stretch-induced increases in the intensity of myosin (M2 and M6) and troponin (Tn3) reflections, as well as a reduction in cross-bridge radial spacing. Independent fluorescent probe analyses in relaxed permeabilized myocytes corroborated these findings. X-ray electron density reconstruction revealed increased mass/ordering in both thick and thin filaments. The SL-dependent changes in structure observed in WT myocardium were absent in HM myocardium. Overall, our results reveal a correlation between titin strain and the Frank–Starling mechanism. The molecular basis underlying this phenomenon appears not to involve interfilament spacing or movement of myosin toward actin but, rather, sarcomere stretch-induced simultaneous structural rearrangements within both thin and thick filaments that correlate with titin strain and myofilament LDA. PMID:26858417

Free vibrations of a multilayered non-circular cylindrical shell

NASA Astrophysics Data System (ADS)

Zelinskaya, Anna V.

2018-05-01

Free vibrations of an elastic non-circular cylindrical shell of intermediate length are considered. The shell is assumed heterogeneous in the thickness direction, in its part it may be multilayered. In order to derive the equations of stability, we use the Timoshenko-Reissner model. According to it, a shell that is heterogeneous can be replaced by a homogeneous shell with the equivalent bending and transversal shear stiffness. We obtain the approximate asymptotic formula for a frequency that takes into account an influence of a transversal shear and a variability of a directrix curvature. As an example, a three-layer elliptical shell with hinged edges and a soft middle layer is analyzed.

Lower limb mechanics during moderate high-heel jogging and running in different experienced wearers.

PubMed

Fu, Fengqin; Zhang, Yan; Shu, Yang; Ruan, Guoqing; Sun, Jianjun; Baker, Julien S; Gu, Yaodong

2016-08-01

The aim of this study is to investigate the differences in lower limb kinematics and kinetics between experienced (EW) and inexperienced (IEW) moderate high-heel wearers during jogging and running. Eleven experienced female wearers of moderate high-heel shoes and eleven matched controls participated in jogging and running tests. A Vicon motion analysis system was used to capture kinematic data and a Kistler force platform was used to collect ground reaction force (GRF). There were no significant differences in jogging and running speed respectively. Compared with IEW, EW adopted larger stride length (SL) with lower stride frequency (SF) at each corresponding speed. During running, EW enlarged SL significantly while IEW increased both SL and SF significantly. Kinematic data showed that IEW had generally larger joint range of motion (ROM) and peak angles during stance phase. Speed effect was not obvious within IEW. EW exhibited a significantly increased maximal vertical GRF (Fz2) and vertical average loading rate (VALR) during running, which was potentially caused by overlong stride. These suggest that both EW and IEW are at high risk of joint injuries when running on moderate high heels. For wearers who have to do some running on moderate high heels, it is crucial to control joint stability and balance SL and SF consciously. Copyright © 2016 Elsevier B.V. All rights reserved.

Genome-wide identification of galactinol synthase (GolS) genes in Solanum lycopersicum and Brachypodium distachyon.

PubMed

Filiz, Ertugrul; Ozyigit, Ibrahim Ilker; Vatansever, Recep

2015-10-01

GolS genes stand as potential candidate genes for molecular breeding and/or engineering programs in order for improving abiotic stress tolerance in plant species. In this study, a total of six galactinol synthase (GolS) genes/proteins were retrieved for Solanum lycopersicum and Brachypodium distachyon. GolS protein sequences were identified to include glyco_transf_8 (PF01501) domain structure, and to have a close molecular weight (36.40-39.59kDa) and amino acid length (318-347 aa) with a slightly acidic pI (5.35-6.40). The sub-cellular location was mainly predicted as cytoplasmic. S. lycopersicum genes located on chr 1 and 2, and included one segmental duplication while genes of B. distachyon were only on chr 1 with one tandem duplication. GolS sequences were found to have well conserved motif structures. Cis-acting analysis was performed for three abiotic stress responsive elements, including ABA responsive element (ABRE), dehydration and cold responsive elements (DRE/CRT) and low-temperature responsive element (LTRE). ABRE elements were found in all GolS genes, except for SlGolS4; DRE/CRT was not detected in any GolS genes and LTRE element found in SlGolS1 and BdGolS1 genes. AU analysis in UTR and ORF regions indicated that SlGolS and BdGolS mRNAs may have a short half-life. SlGolS3 and SlGolS4 genes may generate more stable transcripts since they included AATTAAA motif for polyadenylation signal POLASIG2. Seconder structures of SlGolS proteins were well conserved than that of BdGolS. Some structural divergences were detected in 3D structures and predicted binding sites exhibited various patterns in GolS proteins. Copyright © 2015 Elsevier Ltd. All rights reserved.

Growth and mortality of age-0 northern squawfish, Ptychocheilus oregonensis, rearing in shoreline habitats of the Columbia River Reservoir

USGS Publications Warehouse

Barfoot, C.A.; Gadomski, D.M.; Wertheimer, R.H.

1999-01-01

We investigated growth and mortality of age-0 northern squawfish during early rearing in shallow shoreline habitats. Larvae and juveniles (n=22914) were collected by weekly seining at three sample sites in the upper John Day Reservoir, Columbia River, during June through early September 1994–1996. Using a length-based ageing method, it was estimated that the exponential growth rate (G) for a common growth stanza (10–28 mm standard length SL) was significantly higher in 1994 (G=0.047) than in 1996 (G=0.037). Growth rate in 1995 could not be estimated, but was probably intermediate between 1994 and 1996 based on mean standard lengths of fish collected at the end of each sampling season (46.3, 40.0, and 32.0 mm SL in 1994, 1995, and 1996, respectively). For many fish species, variations in early growth can influence survival through size-selective mortality processes. Consistent with this possibility, our estimates of instantaneous mortality rates (Z) demonstrated that larvae and juveniles had significantly higher mortality in 1996 than in 1994 (Z=0.103 in 1994, versus Z=0.138 in 1996). Enhanced growth and lower mortality in 1994 were associated with a number of interrelated environmental conditions – comparatively low flows and turbidities, abundant instream vegetative cover, and high near-shore water temperatures.

Perceived empty duration between sounds of different lengths: Possible relation with repetition and rhythmic grouping.

PubMed

Kuroda, Tsuyoshi; Tomimatsu, Erika; Grondin, Simon; Miyazaki, Makoto

2016-11-01

We investigated how perceived duration of empty time intervals would be modulated by the length of sounds marking those intervals. Three sounds were successively presented in Experiment 1. Each sound was short (S) or long (L), and the temporal position of the middle sound's onset was varied. The lengthening of each sound resulted in delayed perception of the onset; thus, the middle sound's onset had to be presented earlier in the SLS than in the LSL sequence so that participants perceived the three sounds as presented at equal interonset intervals. In Experiment 2, a short sound and a long sound were alternated repeatedly, and the relative duration of the SL interval to the LS interval was varied. This repeated sequence was perceived as consisting of equal interonset intervals when the onsets of all sounds were aligned at physically equal intervals. If the same onset delay as in the preceding experiment had occurred, participants should have perceived equality between the interonset intervals in the repeated sequence when the SL interval was physically shortened relative to the LS interval. The effects of sound length seemed to be canceled out when the presentation of intervals was repeated. Finally, the perceived duration of the interonset intervals in the repeated sequence was not influenced by whether the participant's native language was French or Japanese, or by how the repeated sequence was perceptually segmented into rhythmic groups.

Use of electronarcosis to immobilize juvenile and adult northern pike

USGS Publications Warehouse

Walker, M.K.; Yanke, E.A.; Gingerich, W.H.

1994-01-01

Electronarcosis, the immobilization of a fish after an electric current has been applied and discontinued, is a potential alternative to chemical anesthetics. Successful narcosis was defined as the immobilization of a fish for 1-15 min without causing physical damage. In the laboratory, AC successfully narcotized juvenile (13-19-cm standard length, SL) northern pike (Esox lucius) at selected voltages; however, AC voltages that produced narcosis or resulted in physical damage were variable and unpredictable. In contrast, 60-90-V pulsed DC (PDC) for 10-60 s successfully narcotized juvenile pike without inducing physical damage. Duration of narcosis was directly related to voltage and inversely related to fish length. In the hatchery, sexually mature northern pike (45-97 cm SL), collected from the Mississippi River, were successfully narcotized by 60-V PDC for 10 s. Duration of narcosis was unrelated to fish length or sex, and averaged 58 plus or minus 7 s (mean plus or minus SE). This allowed sufficient time to collect eggs or milt. All fish were swimming upright within 3 min after treatment, and no mortalities were observed over the next 24 h. Survival of eggs from fertilization to eye- up did not significantly differ between eggs collected from electronarcotized adults and adults anesthetized with MS-222 (tricaine methanesulfonate). Electronarcosis represents a possible alternative to chemical anesthetics for immobilizing northern pike broodstock without an apparent impact on egg survival.

Novel fluorescent core-shell nanocontainers for cell membrane transport.

PubMed

Yin, Meizhen; Kuhlmann, Christoph R W; Sorokina, Ksenia; Li, Chen; Mihov, George; Pietrowski, Eweline; Koynov, Kaloian; Klapper, Markus; Luhmann, Heiko J; Müllen, Klaus; Weil, Tanja

2008-05-01

The synthesis and characterization of novel core-shell macromolecules consisting of a fluorescent perylene-3,4,9,10-tetracarboxdiimide chromophore in the center surrounded by a hydrophobic polyphenylene shell as a first and a flexible hydrophilic polymer shell as a second layer was presented. Following this strategy, several macromolecules bearing varying polymer chain lengths, different polymer shell densities, and increasing numbers of positive and negative charges were achieved. Because all of these macromolecules reveal a good water solubility, their ability to cross cellular membranes was investigated. In this way, a qualitative relationship between the molecular architecture of these macromolecules and the biological response was established.

Finite Element Analysis of Crack-Path Selection in a Brick and Mortar Structure

NASA Astrophysics Data System (ADS)

Sarrafi-Nour, Reza; Manoharan, Mohan; Johnson, Curtis A.

Many natural composite materials rely on organized architectures that span several length scales. The structures of natural shells such as nacre (mother-of-pearl) and conch are prominent examples of such organizations where the calcium carbonate platelets, the main constituent of natural shells, are held together in an organized fashion within an organic matrix. At one or multiple length scales, these organized arrangements often resemble a brick-and-mortar structure, with calcium carbonate platelets acting as bricks connected through the organic mortar phase.

Taxonomy of the early life stages of arrowtooth flounder (Atheresthes stomias) and Kamchatka flounder (A. evermanni) in the eastern Bering Sea, with notes on distribution and condition

NASA Astrophysics Data System (ADS)

De Forest, Lisa; Duffy-Anderson, J. T.; Heintz, R. A.; Matarese, A. C.; Siddon, E. C.; Smart, T. I.; Spies, I. B.

2014-11-01

Arrowtooth flounder (Atheresthes stomias) and Kamchatka flounder (A. evermanni) are closely related flatfish species that co-occur in the eastern Bering Sea. As adults, arrowtooth flounder can be distinguished from Kamchatka flounder; however, larvae and early juveniles can only be indentified to the genus level due to morphological similarities. This has precluded studies of ecology for the early life stages of both species in the eastern Bering Sea. In this study, we developed a genetic technique to identify the larvae and early juveniles of the two species using mtDNA cytochrome oxidase subunit I (COI). Genetically identified specimens were then examined to determine a visual identification method based on pigment patterns and morphology. Specimens 6.0-12.0 mm SL and≥18.0 mm SL can be identified to the species level, but species identification of individuals 12.1-17.9 mm SL by visual means alone remains elusive. The distribution of larvae (<25.0 mm SL) of both arrowtooth flounder and Kamchatka flounder is similar in the eastern Bering Sea; however, juvenile (≥25.0 mm SL) Kamchatka flounder occur closer to the shelf break and in deeper water than juvenile arrowtooth flounder. Condition was determined for larvae and juveniles of each species by analyzing lipid content (%) and energy density (kJ/g dry mass). Kamchatka flounder larvae on average had higher lipid content than arrowtooth flounder larvae, but were also larger on average than arrowtooth flounder larvae in the summer. When corrected for length, both species had similar lipid content in the larval and juvenile stages.

Hydraulic architecture and tracheid allometry in mature Pinus palustris and Pinus elliottii trees.

PubMed

Gonzalez-Benecke, C A; Martin, T A; Peter, G F

2010-03-01

Pinus palustris Mill. (longleaf pine, LL) and Pinus elliottii Engelm. var. elliottii (slash pine, SL) frequently co-occur in lower coastal plain flatwoods of the USA, with LL typically inhabiting slightly higher and better-drained microsites than SL. The hydraulic architecture and tracheid dimensions of roots, trunk and branches of mature LL and SL trees were compared to understand their role in species microsite occupation. Root xylem had higher sapwood-specific hydraulic conductivity (k(s)) and was less resistant to cavitation compared with branches and trunk sapwood. Root k(s) of LL was significantly higher than SL, whereas branch and trunk k(s) did not differ between species. No differences in vulnerability to cavitation were observed in any of the organs between species. Across all organs, there was a significant but weak trade-off between water conduction efficiency and safety. Tracheid hydraulic diameter (D(h)) was strongly correlated with k(s) across all organs, explaining >73% of the variation in k(s). In contrast, tracheid length (L(t)) explained only 2.4% of the variability. Nevertheless, for trunk xylem, k(s) was 39.5% higher at 20 m compared with 1.8 m; this increase in k(s) was uncorrelated with D(h) and cell-wall thickness but was strongly correlated with the difference in L(t). Tracheid allometry markedly changed between sapwood of roots, trunks and branches, possibly reflecting different mechanical constraints. Even though vulnerability to cavitation was not different for sapwood of roots, branches or the trunks of LL and SL, higher sapwood to leaf area ratio and higher maximum sapwood-specific hydraulic conductivity in roots of LL are functional traits that may provide LL with a competitive advantage on drier soil microsites.

Tissue-engineered collateral ligament composite allografts for scapholunate ligament reconstruction: an experimental study.

PubMed

Endress, Ryan; Woon, Colin Y L; Farnebo, Simon J; Behn, Anthony; Bronstein, Joel; Pham, Hung; Yan, Xinrui; Gambhir, Sanjiv S; Chang, James

2012-08-01

In patients with chronic scapholunate (SL) dissociation or dynamic instability, ligament repair is often not possible, and surgical reconstruction is indicated. The ideal graft ligament would recreate both anatomical and biomechanical properties of the dorsal scapholunate ligament (dorsal SLIL). The finger proximal interphalangeal joint (PIP joint) collateral ligament could possibly be a substitute ligament. We harvested human PIP joint collateral ligaments and SL ligaments from 15 cadaveric limbs. We recorded ligament length, width, and thickness, and measured the biomechanical properties (ultimate load, stiffness, and displacement to failure) of native dorsal SLIL, untreated collateral ligaments, decellularized collateral ligaments, and SL repairs with bone-collateral ligament-bone composite collateral ligament grafts. As proof of concept, we then reseeded decellularized bone-collateral ligament-bone composite grafts with green fluorescent protein-labeled adipo-derived mesenchymal stem cells and evaluated them histologically. There was no difference in ultimate load, stiffness, and displacement to failure among native dorsal SLIL, untreated and decellularized collateral ligaments, and SL repairs with tissue-engineered collateral ligament grafts. With pair-matched untreated and decellularized scaffolds, there was no difference in ultimate load or stiffness. However, decellularized ligaments revealed lower displacement to failure compared with untreated ligaments. There was no difference in displacement between decellularized ligaments and native dorsal SLIL. We successfully decellularized grafts with recently described techniques, and they could be similarly reseeded. Proximal interphalangeal joint collateral ligament-based bone-collateral ligament-bone composite allografts had biomechanical properties similar to those of native dorsal SLIL. Decellularization did not adversely affect material properties. These tissue-engineered grafts may offer surgeons another option for reconstruction of chronic SL instability. Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Experiment to evaluate feasibility of utilizing Skylab-EREP remote sensing data for tectonic analysis of the Bighorn Mountains region, Wyoming-Montana

NASA Technical Reports Server (NTRS)

Hoppin, R. A. (Principal Investigator)

1974-01-01

The author has identified the following significant results. S-190A color transparencies from SL-2 of the Big Horn basin region provide the best format to date for geologic study of that region; red beds are quite mappable and resistant key beds sharply outlined. An S-190B color frame from SL-3 of the Pryor-Bighorn mountains provides no indication that the Nye-Bowler lineament extends east of East Pryor Mountain. This has important implications regarding the role of this and other lineaments (which also appear to be of restricted length) in the tectonics of the region. Extensions of these lineaments for great distances does not seem warranted on the basis of surface evidence.

Application of the line-spring model to a cylindrical shell containing a circumferential or axial part-through crack

NASA Technical Reports Server (NTRS)

Delale, F.; Erdogan, F.

1981-01-01

An approximate solution was obtained for a cylindrical shell containing a part-through surface crack. It was assumed that the shell contains a circumferential or axial semi-elliptic internal or external surface crack and was subjected to a uniform membrane loading or a uniform bending moment away from the crack region. A Reissner type theory was used to account for the effects of the transverse shear deformations. The stress intensity factor at the deepest penetration point of the crack was tabulated for bending and membrane loading by varying three dimensionless length parameters of the problem formed from the shell radius, the shell thickness, the crack length, and the crack depth. The upper bounds of the stress intensity factors are provided by the results of the elasticity solution obtained from the axisymmetric crack problem for the circumferential crack, and that found from the plane strain problem for a circular ring having a radial crack for the axial crack. The line-spring model gives the expected results in comparison with the elasticity solutions. Results also compare well with the existing finite element solution of the pressurized cylinder containing an internal semi-elliptic surface crack.

Sacramento Valley, CA, USA

NASA Image and Video Library

1973-06-22

SL2-04-179 (22 June 1973) --- The Sacramento Valley (40.5N, 121.5W) of California is the northern extension of the Central Valley, main agriculture region of the state. Hundreds of truck farms, vineyards and orchards can be seen throughout the length and breadth of the valley which was reclaimed from the desert by means of intensive and extensive irrigation projects. Photo credit: NASA

Predation environment affects boldness temperament of neotropical livebearers.

PubMed

Rasmussen, Josh E; Belk, Mark C

2017-05-01

Behavioral traits of individuals are important phenotypes that potentially interact with many other traits, an understanding of which may illuminate the evolutionary forces affecting populations and species. Among the five axes of temperament is the propensity to behave boldly in the presence of a perceived risk. To determine the effect of different predatorial regimes on boldness and fearfulness, we assessed the behavior of individuals in a novel portable swim chamber (i.e., forced open-field test) by Brachyrhaphis rhabdophora ( n  = 633). We used an information theoretic framework to compare generalized (logistic) linear fixed-effects models of predatorial regime (predator-free [ n  = 6] and predator [ n  = 4] sites), sex, and standard length (SL). Fish from predator sites were much more fearful in the novel arena than fish from nonpredator sites. This varied by length, but not by sex. At 48 mm SL, fish from nonpredator sites were 4.9 times more likely to express bold behavior (ambulation) in the novel swim chamber as fish from predator sites. Probabilities of "ambulating" within the swim chamber increased with size for nonpredator sites and decreased with size for predator sites.

Evaluation of the Mechanical Properties and Effectiveness of Countermine Boots.

DTIC Science & Technology

1998-03-01

regarding comfort except that the 60 shanks overall length of approximately 5.7 in should allow normal flexure of the forefoot . Weight, however, is...When the electron beam strikes an element in the sample, electrons are ejected from inner atomic shells to outer shells resulting in ions in the

Fracture mechanics analyses of partial crack closure in shell structures

NASA Astrophysics Data System (ADS)

Zhao, Jun

2007-12-01

This thesis presents the theoretical and finite element analyses of crack-face closure behavior in shells and its effect on the stress intensity factor under a bending load condition. Various shell geometries, such as spherical shell, cylindrical shell containing an axial crack, cylindrical shell containing a circumferential crack and shell with double curvatures, are all studied. In addition, the influence of material orthotropy on the crack closure effect in shells is also considered. The theoretical formulation is developed based on the shallow shell theory of Delale and Erdogan, incorporating the effect of crack-face closure at the compressive edges. The line-contact assumption, simulating the crack-face closure at the compressive edges, is employed so that the contact force at the closure edges is introduced, which can be translated to the mid-plane of the shell, accompanied by an additional distributed bending moment. The unknown contact force is computed by solving a mixed-boundary value problem iteratively, that is, along the crack length, either the normal displacement of the crack face at the compressive edges is equal to zero or the contact pressure is equal to zero. It is found that due to the curvature effects crack closure may not always occur on the entire length of the crack, depending on the direction of the bending load and the geometry of the shell. The crack-face closure influences significantly the magnitude of the stress intensity factors; it increases the membrane component but decreases the bending component. The maximum stress intensity factor is reduced by the crack-face closure. The significant influence of geometry and material orthotropy on rack closure behavior in shells is also predicted based on the analytical solutions. Three-dimensional FEA is performed to validate the theoretical solutions. It demonstrates that the crack face closure occurs actually over an area, not on a line, but the theoretical solutions of the stress intensity factor and the FEA solutions are in good agreement, because the contact area is very small compared with the shell thickness.

Infrared length scale and extrapolations for the no-core shell model

DOE PAGES

Wendt, K. A.; Forssén, C.; Papenbrock, T.; ...

2015-06-03

In this paper, we precisely determine the infrared (IR) length scale of the no-core shell model (NCSM). In the NCSM, the A-body Hilbert space is truncated by the total energy, and the IR length can be determined by equating the intrinsic kinetic energy of A nucleons in the NCSM space to that of A nucleons in a 3(A-1)-dimensional hyper-radial well with a Dirichlet boundary condition for the hyper radius. We demonstrate that this procedure indeed yields a very precise IR length by performing large-scale NCSM calculations for 6Li. We apply our result and perform accurate IR extrapolations for bound statesmore » of 4He, 6He, 6Li, and 7Li. Finally, we also attempt to extrapolate NCSM results for 10B and 16O with bare interactions from chiral effective field theory over tens of MeV.« less

[Length and structure of telomeric DNA in three species of Baikal gastropods (Caenogastropoda: Hydrobioidea: Benedictiidae)].

PubMed

Koroleva, A G; Evtushenko, E V; Maximova, N V; Vershinin, A V; Sintnikova, T Y; Kirilchik, S V

2015-03-01

The structure of telomeric repeat (TTAGGG)n was determined and the length of telomeric DNA (tDNA) was measured in three species of gastropods from the family Benedictiidae that are endemic to Lake Baikal. Fluorescence in situ hybridization (FISH) confirmed the localization of a telomeric repeat at the chromosome ends. The sizes of tDNA in "giant" eurybathic, psammo-pelobiontic species Benedictia fragilis and shallow water litho-psammobiontic species B. baicalensis with medium shell sizes were similar (16 ± 2.9 and 15 ± 2.1 kb, respectively), but they had a greater length than that of the shallow water spongio-litobiontic species Kobeltocochlea martensiana with small shells (10.5 ± 1.5 kb). We discuss tendencies in age-related changes in tDNA length in snails and a possible mechanism for maintaining tDNA size in ontogeny.

Ellipsoidal all-dielectric Fano resonant core-shell metamaterials

NASA Astrophysics Data System (ADS)

Reena, Reena; Kalra, Yogita; Kumar, Ajeet

2018-06-01

In this paper, ellipsoidal core (Si) and shell (SiO2) metamaterial has been proposed for highly directional properties. At the wavelength of magnetic resonance, Fano dip occurs in the backward scattering cross section and forward scattering enhancement takes place at the same wavelength so that there is an increment in the directivity. Effect on the directivity by changing the length of ellipsoidal nanoparticle along semi-axes has been analyzed. Two Fano resonances have been observed by decreasing the length of the nanoparticle along the semi-axis having electric polarization, where first and second Fano resonances are attributed to the dipole and quadrupole moments, respectively. These Fano resonant wavelengths in ellipsoidal nanoparticle exhibit higher directivity than the Kerker's type scattering or forward scattering shown by symmetrical structures like sphere. So, this core-shell metamaterial can act as an efficient directional nanoantenna.

Titin strain contributes to the Frank–Starling law of the heart by structural rearrangements of both thin- and thick-filament proteins

DOE PAGES

Ait-Mou, Younss; Hsu, Karen; Farman, Gerrie P.; ...

2016-02-08

The Frank–Starling mechanism of the heart is due, in part, to modulation of myofilament Ca 2+ sensitivity by sarcomere length (SL) [length-dependent activation (LDA)]. The molecular mechanism(s) that underlie LDA are unknown. Recent evidence has implicated the giant protein titin in this cellular process, possibly by positioning the myosin head closer to actin. To clarify the role of titin strain in LDA, we isolated myocardium from either WT or homozygous mutant (HM) rats that express a giant splice isoform of titin, and subjected the muscles to stretch from 2.0 to 2.4 μm of SL. Upon stretch, HM compared with WTmore » muscles displayed reduced passive force, twitch force, and myofilament LDA. Time-resolved small-angle X-ray diffraction measurements of WT twitching muscles during diastole revealed stretch-induced increases in the intensity of myosin (M2 and M6) and troponin (Tn3) reflections, as well as a reduction in cross-bridge radial spacing. Independent fluorescent probe analyses in relaxed permeabilized myocytes corroborated these findings. X-ray electron density reconstruction revealed increased mass/ordering in both thick and thin filaments. The SL-dependent changes in structure observed in WT myocardium were absent in HM myocardium. Overall, our results reveal a correlation between titin strain and the Frank–Starling mechanism. The molecular basis underlying this phenomenon appears not to involve interfilament spacing or movement of myosin toward actin but, rather, sarcomere stretch-induced simultaneous structural rearrangements within both thin and thick filaments that correlate with titin strain and myofilament LDA.« less

Multiscale multifractal detrended-fluctuation analysis of two-dimensional surfaces

NASA Astrophysics Data System (ADS)

Wang, Fang; Fan, Qingju; Stanley, H. Eugene

2016-04-01

Two-dimensional (2D) multifractal detrended fluctuation analysis (MF-DFA) has been used to study monofractality and multifractality on 2D surfaces, but when it is used to calculate the generalized Hurst exponent in a fixed time scale, the presence of crossovers can bias the outcome. To solve this problem, multiscale multifractal analysis (MMA) was recent employed in a one-dimensional case. MMA produces a Hurst surface h (q ,s ) that provides a spectrum of local scaling exponents at different scale ranges such that the positions of the crossovers can be located. We apply this MMA method to a 2D surface and identify factors that influence the results. We generate several synthesized surfaces and find that crossovers are consistently present, which means that their fractal properties differ at different scales. We apply MMA to the surfaces, and the results allow us to observe these differences and accurately estimate the generalized Hurst exponents. We then study eight natural texture images and two real-world images and find (i) that the moving window length (WL) and the slide length (SL) are the key parameters in the MMA method, that the WL more strongly influences the Hurst surface than the SL, and that the combination of WL =4 and SL =4 is optimal for a 2D image; (ii) that the robustness of h (2 ,s ) to four common noises is high at large scales but variable at small scales; and (iii) that the long-term correlations in the images weaken as the intensity of Gaussian noise and salt and pepper noise is increased. Our findings greatly improve the performance of the MMA method on 2D surfaces.

Titin strain contributes to the Frank–Starling law of the heart by structural rearrangements of both thin- and thick-filament proteins

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

Ait-Mou, Younss; Hsu, Karen; Farman, Gerrie P.

The Frank–Starling mechanism of the heart is due, in part, to modulation of myofilament Ca 2+ sensitivity by sarcomere length (SL) [length-dependent activation (LDA)]. The molecular mechanism(s) that underlie LDA are unknown. Recent evidence has implicated the giant protein titin in this cellular process, possibly by positioning the myosin head closer to actin. To clarify the role of titin strain in LDA, we isolated myocardium from either WT or homozygous mutant (HM) rats that express a giant splice isoform of titin, and subjected the muscles to stretch from 2.0 to 2.4 μm of SL. Upon stretch, HM compared with WTmore » muscles displayed reduced passive force, twitch force, and myofilament LDA. Time-resolved small-angle X-ray diffraction measurements of WT twitching muscles during diastole revealed stretch-induced increases in the intensity of myosin (M2 and M6) and troponin (Tn3) reflections, as well as a reduction in cross-bridge radial spacing. Independent fluorescent probe analyses in relaxed permeabilized myocytes corroborated these findings. X-ray electron density reconstruction revealed increased mass/ordering in both thick and thin filaments. The SL-dependent changes in structure observed in WT myocardium were absent in HM myocardium. Overall, our results reveal a correlation between titin strain and the Frank–Starling mechanism. The molecular basis underlying this phenomenon appears not to involve interfilament spacing or movement of myosin toward actin but, rather, sarcomere stretch-induced simultaneous structural rearrangements within both thin and thick filaments that correlate with titin strain and myofilament LDA.« less

Performance Simulation of Unipolar InAs/InAs1-x Sb x Type-II Superlattice Photodetector

NASA Astrophysics Data System (ADS)

Singh, Anand; Pal, Ravinder

2018-05-01

This paper reports performance simulation of a unipolar tunable band gap InAs-InAsSb type-II superlattice (T2SL) infrared photodetector. The generation-recombination and surface leakage currents limit the performance of T2SL photodiodes. Unipolar nBn device design incorporating a suitable barrier layer in the diode structure is taken to suppress the Auger recombination and tunneling currents. At low reverse bias, the generation-recombination current is negligible in the absence of a depletion region, but the dark current is dominated by the diffusion current at higher operation temperatures. The composition, band alignment, barrier width, doping level and thickness of the absorber region are optimized here to achieve low dark current and high quantum efficiency at elevated operating temperatures. Thin unipolar T2SL absorbers are placed in a resonant cavity to enhance photon-material interaction, thus allowing complete absorption in a thinner detector element. It leads to the reduction in the detector volume for lower dark current without affecting the quantum efficiency. It shows an improvement in the quantum efficiency and reduction in the dark current. Dark current density ˜ 10-5 A/cm2 is achievable with low absorber thickness of 2 μm and effective lifetime of 250 ns in the InAs/InAs0.6Sb0.4/B-AlAs1-x Sb x long wave length T2SL detector at 110 K.

Medium-chain, triglyceride-containing lipid emulsions increase human neutrophil beta2 integrin expression, adhesion, and degranulation.

PubMed

Wanten, G J; Geijtenbeek, T B; Raymakers, R A; van Kooyk, Y; Roos, D; Jansen, J B; Naber, A H

2000-01-01

To test the hypothesis that lipid emulsions with different triglyceride structures have distinct immunomodulatory properties, we analyzed human neutrophil adhesion and degranulation after lipid incubation. Neutrophils, isolated from the blood of 10 healthy volunteers, were incubated in medium or physiologic (2.5 mmol/L) emulsions containing long-chain (LCT), medium-chain (MCT), mixed LCT/MCT, or structured (SL) triglycerides. Expression of adhesion molecules and degranulation markers was evaluated by flow cytometry. Also, functional adhesion was investigated by means of a flow cytometric assay using fluorescent beads coated with the integrin ligand intercellular adhesion molecule (ICAM)-1. Although LCT and SL had no effect, LCT/MCT significantly increased expression of the beta2 integrins lymphocyte-function-associated antigen 1 (+18%), macrophage antigen 1 (+387%), p150,95 (+82%), and (alphaDbeta2 (+230%). Degranulation marker expression for azurophilic (CD63, +210%) and specific granules (CD66b, +370%) also significantly increased, whereas L-selectin (CD62L, -70%) decreased. The effects of LCT/MCT were mimicked by the MCT emulsion. ICAM-1 adhesion (% beads bound) was increased by LCT/MCT (34% +/- 4%), whereas LCT (19% +/-3%) and SL (20% +/- 2%) had no effect compared with medium (17% +/- 3%). LCT/MCT and MCT, contrary to LCT and SL emulsions, increased neutrophil beta2 integrin expression, adhesion, and degranulation. Apart from other emulsion constituents, triglyceride chain length might therefore be a key feature in the interaction of lipid emulsions and the phagocyte immune system.

Impact of minimum catch size on the population viability of Strombus gigas (Mesogastropoda: Strombidae) in Quintana Roo, Mexico.

PubMed

Peel, Joanne R; Mandujano, María del Carmen

2014-12-01

The queen conch Strombus gigas represents one of the most important fishery resources of the Caribbean but heavy fishing pressure has led to the depletion of stocks throughout the region, causing the inclusion of this species into CITES Appendix II and IUCN's Red-List. In Mexico, the queen conch is managed through a minimum fishing size of 200 mm shell length and a fishing quota which usually represents 50% of the adult biomass. The objectives of this study were to determine the intrinsic population growth rate of the queen conch population of Xel-Ha, Quintana Roo, Mexico, and to assess the effects of a regulated fishing impact, simulating the extraction of 50% adult biomass on the population density. We used three different minimum size criteria to demonstrate the effects of minimum catch size on the population density and discuss biological implications. Demographic data was obtained through capture-mark-recapture sampling, collecting all animals encountered during three hours, by three divers, at four different sampling sites of the Xel-Ha inlet. The conch population was sampled each month between 2005 and 2006, and bimonthly between 2006 and 2011, tagging a total of 8,292 animals. Shell length and lip thickness were determined for each individual. The average shell length for conch with formed lip in Xel-Ha was 209.39 ± 14.18 mm and the median 210 mm. Half of the sampled conch with lip ranged between 200 mm and 219 mm shell length. Assuming that the presence of the lip is an indicator for sexual maturity, it can be concluded that many animals may form their lip at greater shell lengths than 200 mm and ought to be considered immature. Estimation of relative adult abundance and densities varied greatly depending on the criteria employed for adult classification. When using a minimum fishing size of 200 mm shell length, between 26.2% and up to 54.8% of the population qualified as adults, which represented a simulated fishing impact of almost one third of the population. When conch extraction was simulated using a classification criteria based on lip thickness, it had a much smaller impact on the population density. We concluded that the best management strategy for S. gigas is a minimum fishing size based on a lip thickness, since it has lower impact on the population density, and given that selective fishing pressure based on size may lead to the appearance of small adult individuals with reduced fecundity. Furthermore, based on the reproductive biology and the results of the simulated fishing, we suggest a minimum lip thickness of ≥ 15 mm, which ensures the protection of reproductive stages, reduces the risk of overfishing, leading to non-viable density reduction.

Comparative effect of implant-abutment connections, abutment angulations, and screw lengths on preloaded abutment screw using three-dimensional finite element analysis: An in vitro study.

PubMed

Kanneganti, Krishna Chaitanya; Vinnakota, Dileep Nag; Pottem, Srinivas Rao; Pulagam, Mahesh

2018-01-01

The purpose of this study is to compare the effect of implant-abutment connections, abutment angulations, and screw lengths on screw loosening (SL) of preloaded abutment using three dimensional (3D) finite element analysis. 3D models of implants (conical connection with hex/trilobed connections), abutments (straight/angulated), abutment screws (short/long), and crown and bone were designed using software Parametric Technology Corporation Creo and assembled to form 8 simulations. After discretization, the contact stresses developed for 150 N vertical and 100 N oblique load applications were analyzed, using ABAQUS. By assessing damage initiation and shortest fatigue load on screw threads, the SL for 2.5, 5, and 10 lakh cyclic loads were estimated, using fe-safe program. The obtained values were compared for influence of connection design, abutment angulation, and screw length. In straight abutment models, conical connection showed more damage (14.3%-72.3%) when compared to trilobe (10.1%-65.73%) at 2.5, 5, and 10 lakh cycles for both vertical and oblique loads, whereas in angulated abutments, trilobe (16.1%-76.9%) demonstrated more damage compared to conical (13.5%-70%). Irrespective of the connection type and abutment angulation, short screws showed more percentage of damage compared to long screws. The present study suggests selecting appropriate implant-abutment connection based on the abutment angulation, as well as preferring long screws with more number of threads for effective preload retention by the screws.

Hen genetic strain and extended cold storage influence on physical egg quality from cage-free aviary housing system.

PubMed

Jones, D R; Karcher, D M; Regmi, P; Robison, C O; Gast, R K

2018-04-02

In the United States, there is an increase in need for cage-free eggs in retail and food manufacturing sectors. Understanding the impact of cage-free systems and the corresponding management on egg quality is pertinent as the U.S. industry adapts existing housing and builds new cage-free housing structures. A study was conducted comparing 2 brown shell and 2 white shell hen strains housed in a cage-free aviary system. Each set of eggs were placed in cold storage and assessed at 0, 2, 4, 8, and 12 wk. Eggs were collected at 21, 31, 42, and 60 wk of hen age. A full profile of physical quality measurements was conducted on up to 18 intact eggs for each hen strain/egg storage/hen age combination. Egg weight increased approximately 10 g for brown shell and 14 g for white shell eggs as hens aged. Many of the properties monitored were significantly impacted by all 3 main effects (hen strain, egg storage, and hen age) resulting in 3-way interactions. A brown and a white shell strain had stronger shells (44 N; P < 0.0001) than the remaining brown and white shell strains (42 N and 39 N, respectively). The current study also determined volume of shell, total length, maximum width, and percent length at maximum width to more accurately indicate egg shape than shape index. One brown shell strain produced eggs with the most consistent shape characteristics over the hen ages monitored. White shell eggs from the cage-free aviary housing produced the highest whole-egg total solids between 31 to 60 wk of hen age, whereas brown shell eggs resulted in the most consistent level of whole-egg total solids (22-23.5%). The brown and white shell strains in the current study produce cage-free aviary eggs with distinctive physical quality attributes. The outcomes from this study can be utilized by the U.S. egg industry in planning management strategies and market placement of cage-free eggs.

Interactions of ABA signaling core components (SlPYLs, SlPP2Cs, and SlSnRK2s) in tomato (Solanum lycopersicon).

PubMed

Chen, Pei; Sun, Yu-Fei; Kai, Wen-Bin; Liang, Bin; Zhang, Yu-Shu; Zhai, Xia-Wan; Jiang, Li; Du, Yang-Wei; Leng, Ping

2016-10-20

Abscisic acid (ABA) regulates fruit development and ripening via its signaling. However, the exact role of ABA signaling core components in fruit have not yet been clarified. In this study, we investigated the potential interactions of tomato (Solanum lycopersicon) ABA signaling core components using yeast two-hybrid analysis, with or without ABA at different concentrations. The results showed that among 12 PYR/PYL/RCAR ABA receptors (SlPYLs), SlPYL1, SlPYL2, SlPYL4, SlPYL5, SlPYL 7, SlPYL8, SlPYL9, SlPYL10, SlPYL11, and SlPYL13 were ABA-dependent receptors, while SlPYL3 and SlPYL12 were ABA-independent receptors. Among five SlPP2Cs (type 2C protein phosphatases) and seven SlSnRK2s (subfamily 2 of SNF1-related kinases), all SlSnRK2s could interact with SlPP2C2, while SlSnRK2.8 also interacted with SlPP2C3. SlSnRK2.5 could interact with SlABF2/4 (ABA-responsive element binding factors). Expressions of SlPYL1, SlPYL2, SlPYL8, and SlPYL10 were upregulated under exogenous ABA but downregulated under nordihydroguaiaretic acid (NDGA) at the mature green stage of fruit ripening. The expressions of SlPP2C1, SlPP2C2, SlPP2C3, and SlPP2C5 were upregulated in ABA-treated fruit, but downregulated in NDGA-treated fruit at the mature green stage. The expressions of SlSnRK2.4, SlSnRK2.5, SlSnRK2.6, and SlSnRK2.7 were upregulated by ABA, but downregulated by NDGA. However, SlSnRK2.2 was down regulated by ABA. Expression of SlABF2/3/4 was enhanced by ABA but decreased by NDGA. Based on these results, we concluded that the majority of ABA receptor PYLs interact with SlPP2Cs in an ABA-dependent manner. SlPP2C2 and SlPP2C3 can interact with SlSnRK2s. SlSnRK2.5 could interact with SlABF2/4. Most ABA signaling core components respond to exogenous ABA. Copyright © 2016 Elsevier GmbH. All rights reserved.

Sonoluminescence and sonochemiluminescence study of cavitation field in a 1.2MHz focused ultrasound

NASA Astrophysics Data System (ADS)

Yin, Hui; Qiao, Yangzi; Cao, Hua; Wan, Mingxi

2017-03-01

An intensified CCD (ICCD) and an electron-multiplying CCD (EMCCD) were employed to observe the spatial distribution of sonoluminescence (SL) and sonochemiluminescence (SCL) generated by cavitation bubbles in a 1.2MHz HIFU field. Various sonication conditions, which are free field and focal region near a water-parenchyma interface, were studied. In addition, the differences of two shells coated UCAs were also investigated. In this study, an acoustic radiation force (ARF) counterbalance appliance was added to reduce bubble displacement. Cavitation mapping in this situation was also operated through SCL recording. SCL was also employed to measure cavitation does and map the spatial distribution of cavitation near a boundary of parenchyma.

Agarose Gel Electrophoresis Reveals Structural Fluidity of a Phage T3 DNA Packaging Intermediate

PubMed Central

Serwer, Philip; Wright, Elena T.

2012-01-01

We find a new aspect of DNA packaging-associated structural fluidity for phage T3 capsids. The procedure is (1) glutaraldehyde cross-linking of in vivo DNA packaging intermediates for stabilization of structure and then (2) determining of effective radius by two-dimensional agarose gel electrophoresis (2d-AGE). The intermediates are capsids with incompletely packaged DNA (ipDNA) and without an external DNA segment; these intermediates are called ipDNA-capsids. We initially increase production of ipDNA-capsids by raising NaCl concentration during in vivo DNA packaging. By 2d-AGE, we find a new state of contracted shell for some particles of one previously identified ipDNA-capsid. The contracted shell-state is found when ipDNA length/mature DNA length (F) is above 0.17, but not at lower F. Some contracted-shell ipDNA-capsids have the phage tail; others do not. The contracted-shell ipDNA-capsids are explained by premature DNA maturation cleavage that makes accessible a contracted-shell intermediate of a cycle of the T3 DNA packaging motor. The analysis of ipDNA-capsids, rather than intermediates with uncleaved DNA, provides a simplifying strategy for a complete biochemical analysis of in vivo DNA packaging. PMID:22222979

Does the 4f-shell contribute to bonding in tetravalent lanthanide halides?

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

Ji, Wen-Xin; School of Chemistry and Chemical Engineering, Ningxia University, 750015 Yinchuan; Xu, Wei

2014-12-28

Lanthanide tetrahalide molecules LnX{sub 4} (Ln = Ce, Pr, Tb; X = F, Cl, Br, I) have been investigated by density functional theory at the levels of the relativistic Zero Order Regular Approximation and the relativistic energy-consistent pseudopotentials, using frozen small- and medium-cores. The calculated bond lengths and vibrational frequencies are close to the experimental data. Our calculations indicate 4f shell contributions to bonding in LnX{sub 4}, in particular for the early lanthanides, which show significant overlap between the Ln 4f-shell and the halogen np-shells. The 4f shells contribute to Ln-X bonding in LnX{sub 4} about one third more thanmore » in LnX{sub 3}.« less

Morphology of glochidia of Lampsilis higginsi (Bivalvia: Unionidae) compared with three related species

USGS Publications Warehouse

Waller, D.L.; Holland Bartels, L. E.; Mitchell, L.G.

1988-01-01

Glochidia of the endangered unionid mussel Lampsilis higginsi (Lea) are morphologically similar to those of several other species in the upper Mississippi River. Life history details, such as the timing of reproduction and identity of host fish, can be readily studied if the glochidia of L. higginsi can be distinguished from those of related species. Authors used light and scanning electron microscopy and statistical analyses of three shell measurements, shell length, shell height, and hinge length, to compare the glochidia of L. higginsi with those of L. radiata siliquoidea (Barnes), L. ventricosa (Barnes), and Ligumia recta (Lamarck). Glochidia of L. higginsi were differentiated by scanning electron microscopy on the basis of a combined examination of the position of the hinge ligament and the width of dorsal ridges, but were indistinguishable by light microscope examination or by statistical analyses of measurements.

Enhanced linear photonic nanojet generated by core-shell optical microfibers

NASA Astrophysics Data System (ADS)

Liu, Cheng-Yang; Yen, Tzu-Ping; Chen, Chien-Wen

2017-05-01

The generation of linear photonic nanojet using core-shell optical microfiber is demonstrated numerically and experimentally in the visible light region. The power flow patterns for the core-shell optical microfiber are calculated by using the finite-difference time-domain method. The focusing properties of linear photonic nanojet are evaluated in terms of length and width along propagation and transversal directions. In experiment, the silica optical fiber is etched chemically down to 6 μm diameter and coated with metallic thin film by using glancing angle deposition. We show that the linear photonic nanojet is enhanced clearly by metallic shell due to surface plasmon polaritons. The large-area superresolution imaging can be performed by using a core-shell optical microfiber in the far-field system. The potential applications of this core-shell optical microfiber include micro-fluidics and nano-structure measurements.

Anomalous Flexural Behaviors of Microtubules

PubMed Central

Liu, Xiaojing; Zhou, Youhe; Gao, Huajian; Wang, Jizeng

2012-01-01

Apparent controversies exist on whether the persistence length of microtubules depends on its contour length. This issue is particularly challenging from a theoretical point of view due to the tubular structure and strongly anisotropic material property of microtubules. Here we adopt a higher order continuum orthotropic thin shell model to study the flexural behavior of microtubules. Our model overcomes some key limitations of a recent study based on a simplified anisotropic shell model and results in a closed-form solution for the contour-length-dependent persistence length of microtubules, with predictions in excellent agreement with experimental measurements. By studying the ratio between their contour and persistence lengths, we find that microtubules with length at ∼1.5 μm show the lowest flexural rigidity, whereas those with length at ∼15 μm show the highest flexural rigidity. This finding may provide an important theoretical basis for understanding the mechanical structure of mitotic spindles during cell division. Further analysis on the buckling of microtubules indicates that the critical buckling load becomes insensitive to the tube length for relatively short microtubules, in drastic contrast to the classical Euler buckling. These rich flexural behaviors of microtubules are of profound implication for many biological functions and biomimetic molecular devices. PMID:22768935

Response of moderately thick laminated cross-ply composite shells subjected to random excitation

NASA Technical Reports Server (NTRS)

Elishakoff, Isaak; Cederbaum, Gabriel; Librescu, Liviu

1989-01-01

This study deals with the dynamic response of transverse shear deformable laminated shells subjected to random excitation. The analysis encompasses the following problems: (1) the dynamic response of circular cylindrical shells of finite length excited by an axisymmetric uniform ring loading, stationary in time, and (2) the response of spherical and cylindrical panels subjected to stationary random loadings with uniform spatial distribution. The associated equations governing the structural theory of shells are derived upon discarding the classical Love-Kirchhoff (L-K) assumptions. In this sense, the theory is formulated in the framework of the first-order transverse shear deformation theory (FSDT).

Bio-inspired passive actuator simulating an abalone shell mechanism for structural control

NASA Astrophysics Data System (ADS)

Yang, Henry T. Y.; Lin, Chun-Hung; Bridges, Daniel; Randall, Connor J.; Hansma, Paul K.

2010-10-01

An energy dispersion mechanism called 'sacrificial bonds and hidden length', which is found in some biological systems, such as abalone shells and bones, is the inspiration for new strategies for structural control. Sacrificial bonds and hidden length can substantially increase the stiffness and enhance energy dissipation in the constituent molecules of abalone shells and bone. Having been inspired by the usefulness and effectiveness of such a mechanism, which has evolved over millions of years and countless cycles of evolutions, the authors employ the conceptual underpinnings of this mechanism to develop a bio-inspired passive actuator. This paper presents a fundamental method for optimally designing such bio-inspired passive actuators for structural control. To optimize the bio-inspired passive actuator, a simple method utilizing the force-displacement-velocity (FDV) plots based on LQR control is proposed. A linear regression approach is adopted in this research to find the initial values of the desired parameters for the bio-inspired passive actuator. The illustrative examples, conducted by numerical simulation with experimental validation, suggest that the bio-inspired passive actuator based on sacrificial bonds and hidden length may be comparable in performance to state-of-the-art semi-active actuators.

Impact of titin strain on the cardiac slow force response.

PubMed

Ait-Mou, Younss; Zhang, Mengjie; Martin, Jody L; Greaser, Marion L; de Tombe, Pieter P

2017-11-01

Stretch of myocardium, such as occurs upon increased filling of the cardiac chamber, induces two distinct responses: an immediate increase in twitch force followed by a slower increase in twitch force that develops over the course of several minutes. The immediate response is due, in part, to modulation of myofilament Ca 2+ sensitivity by sarcomere length (SL). The slowly developing force response, termed the Slow Force Response (SFR), is caused by a slowly developing increase in intracellular Ca 2+ upon sustained stretch. A blunted immediate force response was recently reported for myocardium isolated from homozygous giant titin mutant rats (HM) compared to muscle from wild-type littermates (WT). Here, we examined the impact of titin isoform on the SFR. Right ventricular trabeculae were isolated and mounted in an experimental chamber. SL was measured by laser diffraction. The SFR was recorded in response to a 0.2 μm SL stretch in the presence of [Ca 2+ ] o  = 0.4 mM, a bathing concentration reflecting ∼50% of maximum twitch force development at 25 °C. Presence of the giant titin isoform (HM) was associated with a significant reduction in diastolic passive force upon stretch, and ∼50% reduction of the magnitude of the SFR; the rate of SFR development was unaffected. The sustained SL stretch was identical in both muscle groups. Therefore, our data suggest that cytoskeletal strain may underlie directly the cellular mechanisms that lead to the increased intracellular [Ca 2+ ] i that causes the SFR, possibly by involving cardiac myocyte integrin signaling pathways. Copyright © 2017 Elsevier Ltd. All rights reserved.

Karyomorphology and karyotype asymmetry in the South American Caesalpinia species (Leguminosae and Caesalpinioideae).

PubMed

Rodrigues, P S; Souza, M M; Corrêa, R X

2014-10-20

With the purpose of addressing the pattern of karyotype evolution in Caesalpinia species, chromosome morphology was characterized in five species from Brazil, and karyotypic asymmetry was analyzed in 14 species from South America. All accessions had the chromosome number 2n = 24, which was first described here for Caesalpinia laxiflora Tul. and Cenostigma macrophyllum Tul. The karyotype formula of C. laxiflora, Caesalpinia pyramidalis Tul., and C. macrophyllum was 12 m. The formula varies amongst the populations of Caesalpinia bracteosa Tul. (11 m + 1 sm) and Caesalpinia echinata Lam. (10 m + 2 sm and 9 m + 3 sm). The intra- and interspecific variations in chromosome length were significant (analysis of variance, P < 0.05). Analyzing the asymmetry index (AI), revealed that Caesalpinia calycina Benth. had the most asymmetrical karyotype (AI = 10.52), whereas Caesalpinia paraguarienses (D. Parodi) Burkat. and Caesalpinia gilliesii (Hook.) Benth. had the most symmetrical karyotypes (AI = 0.91 and 1.10, respectively). There has been a trend to lower AI values for the Caesalpinia s.l. species assigned in Libidibia and intermediate values for those combined into Poincianella. On the other hand, the karyotypes of Erythrostemon species had extremely different AI values. This study confirms the existence of karyotype variability in Caesalpinia s.l. while revealing a possible uniformity of this trait in some of the new genera that are being divided from Caesalpinia s.l. More broadly, the 2n = 24 chromosome number is conserved. Metacentric chromosomes and low AI values predominate among Caesalpinia s.l. and Cenostigma.

A cytochrome P450 regulates a domestication trait in cultivated tomato

PubMed Central

Chakrabarti, Manohar; Zhang, Na; Sauvage, Christopher; Muños, Stéphane; Blanca, Jose; Cañizares, Joaquin; Diez, Maria Jose; Schneider, Rhiannon; Mazourek, Michael; McClead, Jammi; Causse, Mathilde; van der Knaap, Esther

2013-01-01

Domestication of crop plants had effects on human lifestyle and agriculture. However, little is known about the underlying molecular mechanisms accompanying the changes in fruit appearance as a consequence of selection by early farmers. We report the fine mapping and cloning of a tomato (Solanum lycopersicum) fruit mass gene encoding the ortholog of KLUH, SlKLUH, a P450 enzyme of the CYP78A subfamily. The increase in fruit mass is predominantly the result of enlarged pericarp and septum tissues caused by increased cell number in the large fruited lines. SlKLUH also modulates plant architecture by regulating number and length of the side shoots, and ripening time, and these effects are particularly strong in plants that transgenically down-regulate SlKLUH expression carrying fruits of a dramatically reduced mass. Association mapping followed by segregation analyses revealed that a single nucleotide polymorphism in the promoter of the gene is highly associated with fruit mass. This single polymorphism may potentially underlie a regulatory mutation resulting in increased SlKLUH expression concomitant with increased fruit mass. Our findings suggest that the allele giving rise to large fruit arose in the early domesticates of tomato and becoming progressively more abundant upon further selections. We also detected association of fruit weight with CaKLUH in chile pepper (Capsicum annuum) suggesting that selection of the orthologous gene may have occurred independently in a separate domestication event. Altogether, our findings shed light on the molecular basis of fruit mass, a key domestication trait in tomato and other fruit and vegetable crops. PMID:24082112

Rhodnius barretti, a new species of Triatominae (Hemiptera: Reduviidae) from western Amazonia

PubMed Central

Abad-Franch, Fernando; Pavan, Márcio G; Jaramillo-O, Nicolás; Palomeque, Francisco S; Dale, Carolina; Chaverra, Duverney; Monteiro, Fernando A

2013-01-01

Rhodnius barretti , a new triatomine species, is described based on adult specimens collected in rainforest environments within the Napo ecoregion of western Amazonia (Colombia and Ecuador). R. barretti resembles Rhodnius robustus s.l. , but mitochondrial cytochrome b gene sequences reveal that it is a strongly divergent member of the “robustus lineage”, i.e., basal to the clade encompassing Rhodnius nasutus , Rhodnius neglectus , Rhodnius prolixus and five members of the R. robustus species complex. Morphometric analyses also reveal consistent divergence from R. robustus s.l. , including head and, as previously shown, wing shape and the length ratios of some anatomical structures. R. barretti occurs, often at high densities, in Attalea butyracea and Oenocarpus bataua palms. It is strikingly aggressive and adults may invade houses flying from peridomestic palms. R. barretti must therefore be regarded as a potential Trypanosoma cruzi vector in the Napo ecoregion, where Chagas disease is endemic. PMID:24473808

Control of in vivo disposition and immunogenicity of polymeric micelles by adjusting poly(sarcosine) chain lengths on surface

NASA Astrophysics Data System (ADS)

Kurihara, Kensuke; Ueda, Motoki; Hara, Isao; Ozeki, Eiichi; Togashi, Kaori; Kimura, Shunsaku

2017-07-01

Four kinds of A3B-type amphiphilic polydepsipeptides, (poly(sarcosine))3- b-poly( l-lactic acid) (the degree of polymerization of poly(sarcosine) are 10, 33, 55, and 85; S10 3 , S33 3 , S55 3 , and S85 3 ) were synthesized to prepare core-shell type polymeric micelles. Their in vivo dispositions and stimulations to trigger immune system to produce IgM upon multiple administrations to mice were examined. With increasing poly(sarcosine) chain lengths, the hydrophilic shell became thicker and the surface density at the most outer surface decreased on the basis of dynamic and static light scattering measurements. These two physical elements of polymeric micelles elicited opposite effects on the immune response in light of the chain length therefore to show an optimized poly(sarcosine) chain length existing between 33mer and 55mer to suppress the accelerated blood clearance phenomenon associated with polymeric micelles.

Genomic overview of mRNA 5′-leader trans-splicing in the ascidian Ciona intestinalis

PubMed Central

Satou, Yutaka; Hamaguchi, Makoto; Takeuchi, Keisuke; Hastings, Kenneth E. M.; Satoh, Nori

2006-01-01

Although spliced leader (SL) trans-splicing in the chordates was discovered in the tunicate Ciona intestinalis there has been no genomic overview analysis of the extent of trans-splicing or the make-up of the trans-spliced and non-trans-spliced gene populations of this model organism. Here we report such an analysis for Ciona based on the oligo-capping full-length cDNA approach. We randomly sampled 2078 5′-full-length ESTs representing 668 genes, or 4.2% of the entire genome. Our results indicate that Ciona contains a single major SL, which is efficiently trans-spliced to mRNAs transcribed from a specific set of genes representing ∼50% of the total number of expressed genes, and that individual trans-spliced mRNA species are, on average, 2–3-fold less abundant than non-trans-spliced mRNA species. Our results also identify a relationship between trans-splicing status and gene functional classification; ribosomal protein genes fall predominantly into the non-trans-spliced category. In addition, our data provide the first evidence for the occurrence of polycistronic transcription in Ciona. An interesting feature of the Ciona polycistronic transcription units is that the great majority entirely lack intercistronic sequences. PMID:16822859

Physiological and Perceptual Responses to Nordic Walking in a Natural Mountain Environment

PubMed Central

Grainer, Alessandro; Zerbini, Livio; Reggiani, Carlo; Pavei, Gaspare

2017-01-01

Background: Interest around Nordic Walking (NW) has increased in recent years. However, direct comparisons of NW with normal walking (W), particularly in ecologically valid environments is lacking. The aim of our study was to compare NW and W, over long distances in a natural mountain environment. Methods: Twenty one subjects (13 male/8 female, aged 41 ± 12 years, body mass index BMI 24.1 ± 3.7), walked three distinct uphill paths (length 2.2/3.4/7 km) with (NW) or without (W) walking poles over two separate days. Heart rate (HR), energy expenditure (EE), step length (SL), walking speed (WS), total steps number (SN) and rating of perceived exertion (RPE) were monitored. Results: HR (+18%) and EE (+20%) were higher in NW than in W whilst RPE was similar. SN (−12%) was lower and SL (+15%) longer in NW. WS was higher (1.64 vs. 1.53 m s−1) in NW. Conclusions: Our data confirm that, similarly to previous laboratory studies, differences in a range of walking variables are present between NW and W when performed in a natural environment. NW appears to increase EE compared to W, despite a similar RPE. Thus, NW could be a useful as aerobic training modality for weight control and cardiorespiratory fitness. PMID:29039775

Physiological and Perceptual Responses to Nordic Walking in a Natural Mountain Environment.

PubMed

Grainer, Alessandro; Zerbini, Livio; Reggiani, Carlo; Marcolin, Giuseppe; Steele, James; Pavei, Gaspare; Paoli, Antonio

2017-10-17

Background: Interest around Nordic Walking (NW) has increased in recent years. However, direct comparisons of NW with normal walking (W), particularly in ecologically valid environments is lacking. The aim of our study was to compare NW and W, over long distances in a natural mountain environment. Methods: Twenty one subjects (13 male/8 female, aged 41 ± 12 years, body mass index BMI 24.1 ± 3.7), walked three distinct uphill paths (length 2.2/3.4/7 km) with (NW) or without (W) walking poles over two separate days. Heart rate (HR), energy expenditure (EE), step length (SL), walking speed (WS), total steps number (SN) and rating of perceived exertion (RPE) were monitored. Results: HR (+18%) and EE (+20%) were higher in NW than in W whilst RPE was similar. SN (-12%) was lower and SL (+15%) longer in NW. WS was higher (1.64 vs. 1.53 m s -1 ) in NW. Conclusions: Our data confirm that, similarly to previous laboratory studies, differences in a range of walking variables are present between NW and W when performed in a natural environment. NW appears to increase EE compared to W, despite a similar RPE. Thus, NW could be a useful as aerobic training modality for weight control and cardiorespiratory fitness.

Analysis of transient, linear wave propagation in shells by the finite difference method

NASA Technical Reports Server (NTRS)

Geers, T. L.; Sobel, L. H.

1971-01-01

The applicability of the finite difference method to propagation problems in shells, and the response of a cylindrical shell with cutouts to both longitudinal and radial transient excitations are investigated. It is found that the only inherent limitation of the finite difference method is its inability to reproduce accurately response discontinuities. The short wave length limitations of thin shell theory create significant convergence difficulties may often be overcome through proper selection of finite difference mesh dimensions and temporal or spatial smoothing of the excitation. Cutouts produce moderate changes in early and intermediate time response of a cylindrical shell to axisymmetric pulse loads applied at one end. The cutouts may facilitate the undesirable late-time transfer of load-injected extensional energy into nonaxisymmetric flexural response.

Length-weight and length-length relationships of common carp (Cyprinus carpio L.) in the middle and southern Iraq provinces

NASA Astrophysics Data System (ADS)

Al-jebory, Taymaa A.; Das, Simon K.; Usup, Gires; Bakar, Y.; Al-saadi, Ali H.

2018-04-01

In this study, length-weight and length-length relationships of common carp (Cyprinus carpio L.) in the middle and southern Iraq provinces were determined. Fish specimens were procured from seven provinces from July to December, 2015. A negative and positive allometric growth pattern was obtained, where the total length (TL) ranged from 25.60 cm to 33.53 cm, and body weight (BW) ranged from 700 g to 1423 g. Meanwhile, the lowest of 1.03 and highest of 3.54 in "b" value was recorded in group F and group C, respectively. Therefore, Fulton condition factor (K) range from 2.57 to 4.94. While, relative condition factor (Kn) was in the ranged of 0.95 to 1.01. A linear relationship between total length (TL) and standard length (SL) among the provinces for fish groups was obtained. The variances in "b" value ranged from 0.10 to 0.93 with correlation coefficient (r2) of 0.02 to 0.97. This research could be used as a guide to study the ecology and biology of common Carp (Cyprinus carpio L.) in the middle and southern Iraq provinces.

Effect of Altered Retinal Cones/Opsins on Refractive Development under Monochromatic Lights in Guinea Pigs

PubMed Central

Zou, Leilei; Zhu, Xiaoyu; Liu, Rui; Ma, Fei; Yu, Manrong

2018-01-01

Purpose To analyze the changes of refraction and metabolism of the retinal cones under monochromatic lights in guinea pigs. Methods Sixty guinea pigs were randomly divided into a short-wavelength light (SL) group, a middle-wavelength light (ML) group, and a white light (WL) group. Refraction and axial length were measured before and after 10-week illumination. The densities of S-cones and M-cones were determined by retinal cone immunocytochemistry, and the expressions of S-opsins and M-opsins were determined by real-time PCR and Western blot. Results After 10-week illumination, the guinea pigs developed relative hyperopia in the SL group and relative myopia in the ML group. Compared with the WL group, the density of S-cones and S-opsins increased while M-cones and M-opsins decreased in the SL group (all, p < 0.05); conversely, the density of S-cones and S-opsins decreased while M-cones and M-opsins increased in the ML group (all, p < 0.05). Increased S-cones/opsins and decreased M-cones/opsins were induced by short-wavelength lights. Decreased S-cones/opsins and increased M-cones/opsins were induced by middle-wavelength lights. Conclusions Altered retinal cones/opsins induced by monochromatic lights might be involved in the refractive development in guinea pigs. PMID:29675275

Alburnoides manyasensis (Actinopterygii, Cyprinidae), a new species of cyprinid fish from Manyas Lake basin, Turkey

PubMed Central

Turan, Davut; Ekmekçi, F. Güler; Kaya, Cüneyt; Güçlü, S. Serkan

2013-01-01

Abstract Alburnoides manyasensis, sp. n., is described from the Koca Stream (Lake Manyas drainage, Marmara Sea basin) in Anatolia. It is distinguished from all species of Alburnoides in Turkey and adjacent regions, Alburnoides tzanevi (Rezovska [Rezve], Istranca and Terkos streams in the western Black Sea drainage), Alburnoides cf. smyrnae (Banaz Stream, a drainage of Büyük Menderes River, Aegean Sea basin), Alburnoides fasciatus (streams and rivers in the eastern Black Sea drainage) and Alburnoides eichwaldii (Kura and Aras rivers [a drainage of Kura River], Caspian Sea basin) by a combination of the following characters (none unique to the species):marked hump at nape, especially in specimens larger than 60 mm SL; partly developed ventral keel between pelvic fin and anal fin, scaleless 1/2 to 2/3 its length; body depth at dorsal-fin origin 29−32% SL; caudal peduncle depth 11−12% SL; 45–52+ 2–3 lateral-line scales; 9–12 scale rows between lateral line and dorsal-fin origin; 4–5 scale rows between lateral line and anal-fin origin, 10½–12½ branched anal-fin rays; 40–42 total vertebrae. PMID:23794819

Angiotensin-converting enzyme in Spodoptera littoralis: molecular characterization, expression and activity profile during development.

PubMed

Lemeire, Els; Vanholme, Bartel; Van Leeuwen, Thomas; Van Camp, John; Smagghe, Guy

2008-02-01

The characterization of the full-length angiotensin-converting enzyme (ACE) cDNA sequence of the lepidopteran Spodoptera littoralis is reported in this study. The predicted open reading frame encodes a 647 amino acids long protein (SlACE) and shows 63.6% identity with the Bombyx mori ACE sequence. A 3D-model, consisting of 26 alpha-helices and three beta-sheets, was predicted for the sequence. SlACE expression was studied in the embryonic, larval and pupal stages of S. littoralis and in different tissues of the last larval stage by reverse-transcribed PCR. This revealed that the gene is expressed throughout the life cycle and especially in brain, gut and fat body tissue of the last stage. These results are in agreement with a role of ACE in the metabolism of neuropeptides and gut hormones. In addition, ACE activity has been studied in more detail during development, making use of a fluorescent assay. High ACE peptidase activity coincides with every transition state, from embryo to larva, from larva to larva and from larva to pupa. A peak value in activity occurs during the early pupal stage. These results indicate the importance of SlACE during metamorphosis and reveal the high correlation of ACE activity with the insect's development, which is regulated by growth and developmental hormones.

Fabrication of diamond shells

DOEpatents

Hamza, Alex V.; Biener, Juergen; Wild, Christoph; Woerner, Eckhard

2016-11-01

A novel method for fabricating diamond shells is introduced. The fabrication of such shells is a multi-step process, which involves diamond chemical vapor deposition on predetermined mandrels followed by polishing, microfabrication of holes, and removal of the mandrel by an etch process. The resultant shells of the present invention can be configured with a surface roughness at the nanometer level (e.g., on the order of down to about 10 nm RMS) on a mm length scale, and exhibit excellent hardness/strength, and good transparency in the both the infra-red and visible. Specifically, a novel process is disclosed herein, which allows coating of spherical substrates with optical-quality diamond films or nanocrystalline diamond films.

Sound Shell Model for Acoustic Gravitational Wave Production at a First-Order Phase Transition in the Early Universe.

PubMed

Hindmarsh, Mark

2018-02-16

A model for the acoustic production of gravitational waves at a first-order phase transition is presented. The source of gravitational radiation is the sound waves generated by the explosive growth of bubbles of the stable phase. The model assumes that the sound waves are linear and that their power spectrum is determined by the characteristic form of the sound shell around the expanding bubble. The predicted power spectrum has two length scales, the average bubble separation and the sound shell width when the bubbles collide. The peak of the power spectrum is at wave numbers set by the sound shell width. For a higher wave number k, the power spectrum decreases to k^{-3}. At wave numbers below the inverse bubble separation, the power spectrum goes to k^{5}. For bubble wall speeds near the speed of sound where these two length scales are distinguished, there is an intermediate k^{1} power law. The detailed dependence of the power spectrum on the wall speed and the other parameters of the phase transition raises the possibility of their constraint or measurement at a future space-based gravitational wave observatory such as LISA.

Sound Shell Model for Acoustic Gravitational Wave Production at a First-Order Phase Transition in the Early Universe

NASA Astrophysics Data System (ADS)

Hindmarsh, Mark

2018-02-01

A model for the acoustic production of gravitational waves at a first-order phase transition is presented. The source of gravitational radiation is the sound waves generated by the explosive growth of bubbles of the stable phase. The model assumes that the sound waves are linear and that their power spectrum is determined by the characteristic form of the sound shell around the expanding bubble. The predicted power spectrum has two length scales, the average bubble separation and the sound shell width when the bubbles collide. The peak of the power spectrum is at wave numbers set by the sound shell width. For a higher wave number k , the power spectrum decreases to k-3. At wave numbers below the inverse bubble separation, the power spectrum goes to k5. For bubble wall speeds near the speed of sound where these two length scales are distinguished, there is an intermediate k1 power law. The detailed dependence of the power spectrum on the wall speed and the other parameters of the phase transition raises the possibility of their constraint or measurement at a future space-based gravitational wave observatory such as LISA.

The Effects of Ocean Acidification on Predator-Prey Interactions between Mya arenaria and Callinectes sapidus

NASA Astrophysics Data System (ADS)

Longmire, K.; Glaspie, C.; Seitz, R.

2016-02-01

The study examined the implications of ocean acidification for Mya arenaria and the predator-prey dynamics between M. arenaria and Callinectes sapidus. Clams were subjected to either ambient conditions or acidified conditions and grown over four weeks. Mortality, shell lengths, and biomass (ash-free dry weights) were recorded for clams destructively sampled each week. Clams were subjected to behavioral experiments to determine their response to an approaching physical disturbance. Crabs were exposed to acidified or ambient conditions for 48 hours, and placed in 48 hour mesocosm trials with clams. Shell lengths, mortality and biomass between the ambient and acidified clams were not significantly different between acidified and ambient treatments. Shell ash weights were lower for acidified clams, evidence of shell dissolution. In the behavioral experiment, ocean acidification reduced the ability of clams to respond to a predator stimulus. Lastly, in predator-prey mesocosm trials, in ambient conditions, crabs ate all or none of the available clams, whereas acidified crabs ate all available clams in many trials and ate at least one acidified clam per trial. The early effects of ocean acidification on M. arenaria will manifest in trophic interactions with other species, rather than impacting M. arenaria alone.

Tomato SlMKK2 and SlMKK4 contribute to disease resistance against Botrytis cinerea

PubMed Central

2014-01-01

Background Mitogen-activated protein kinase (MAPK) cascades are highly conserved signaling modules that mediate the transduction of extracellular stimuli via receptors/sensors into intracellular responses and play key roles in plant immunity against pathogen attack. However, the function of tomato MAPK kinases, SlMKKs, in resistance against Botrytis cinerea remains unclear yet. Results A total of five SlMKK genes with one new member, SlMKK5, were identified in tomato. qRT-PCR analyses revealed that expression of SlMKK2 and SlMKK4 was strongly induced by B. cinerea and by jasmonic acid and ethylene precursor 1-amino cyclopropane-1-carboxylic acid. Virus-induced gene silencing (VIGS)-based knockdown of individual SlMKKs and disease assays identified that SlMKK2 and SlMKK4 but not other three SlMKKs (SlMKK1, SlMKK3 and SlMKK5) are involved in resistance against B. cinerea. Silencing of SlMKK2 or SlMKK4 resulted in reduced resistance to B. cinerea, increased accumulation of reactive oxygen species and attenuated expression of defense genes after infection of B. cinerea in tomato plants. Furthermore, transient expression of constitutively active phosphomimicking forms SlMKK2DD and SlMKK4DD in leaves of Nicotiana benthamiana plants led to enhanced resistance to B. cinerea and elevated expression of defense genes. Conclusions VIGS-based knockdown of SlMKK2 and SlMKK4 expression in tomato and gain-of-function transient expression of constitutively active phosphomimicking forms SlMKK2DD and SlMKK2DD in N. benthamiana demonstrate that both SlMKK2 and SlMKK4 function as positive regulators of defense response against B. cinerea. PMID:24930014

Characterization of a Novel Subgroup of Extracellular Medium-Chain-Length Polyhydroxyalkanoate Depolymerases from Actinobacteria

PubMed Central

Gangoiti, Joana; Santos, Marta; Prieto, María Auxiliadora; de la Mata, Isabel; Llama, María J.

2012-01-01

Nineteen medium-chain-length (mcl) poly(3-hydroxyalkanoate) (PHA)-degrading microorganisms were isolated from natural sources. From them, seven Gram-positive and three Gram-negative bacteria were identified. The ability of these microorganisms to hydrolyze other biodegradable plastics, such as short-chain-length (scl) PHA, poly(ε-caprolactone) (PCL), poly(ethylene succinate) (PES), and poly(l-lactide) (PLA), has been studied. On the basis of the great ability to degrade different polyesters, Streptomyces roseolus SL3 was selected, and its extracellular depolymerase was biochemically characterized. The enzyme consisted of one polypeptide chain of 28 kDa with a pI value of 5.2. Its maximum activity was observed at pH 9.5 with chromogenic substrates. The purified enzyme hydrolyzed mcl PHA and PCL but not scl PHA, PES, and PLA. Moreover, the mcl PHA depolymerase can hydrolyze various substrates for esterases, such as tributyrin and p-nitrophenyl (pNP)-alkanoates, with its maximum activity being measured with pNP-octanoate. Interestingly, when poly(3-hydroxyoctanoate-co-3-hydroxyhexanoate [11%]) was used as the substrate, the main hydrolysis product was the monomer (R)-3-hydroxyoctanoate. In addition, the genes of several Actinobacteria strains, including S. roseolus SL3, were identified on the basis of the peptide de novo sequencing of the Streptomyces venezuelae SO1 mcl PHA depolymerase by tandem mass spectrometry. These enzymes did not show significant similarity to mcl PHA depolymerases characterized previously. Our results suggest that these distinct enzymes might represent a new subgroup of mcl PHA depolymerases. PMID:22865072

Egg shell quality in Japanese quail: characteristics, heritabilities and genetic and phenotypic relationships.

PubMed

Narinc, D; Aygun, A; Karaman, E; Aksoy, T

2015-07-01

The objective of the present study was to estimate heritabilities as well as genetic and phenotypic correlations for egg weight, specific gravity, shape index, shell ratio, egg shell strength, egg length, egg width and shell weight in Japanese quail eggs. External egg quality traits were measured on 5864 eggs of 934 female quails from a dam line selected for two generations. Within the Bayesian framework, using Gibbs Sampling algorithm, a multivariate animal model was applied to estimate heritabilities and genetic correlations for external egg quality traits. The heritability estimates for external egg quality traits were moderate to high and ranged from 0.29 to 0.81. The heritability estimates for egg and shell weight of 0.81 and 0.76 were fairly high. The genetic and phenotypic correlations between egg shell strength with specific gravity, shell ratio and shell weight ranging from 0.55 to 0.79 were relatively high. It can be concluded that it is possible to determine egg shell quality using the egg specific gravity values utilizing its high heritability and fairly high positive correlation with most of the egg shell quality traits. As a result, egg specific gravity may be the choice of selection criterion rather than other external egg traits for genetic improvement of egg shell quality in Japanese quails.

Historical baselines and the future of shell calcification for a foundation species in a changing ocean

PubMed Central

Pfister, Catherine A.; Roy, Kaustuv; Wootton, J. Timothy; McCoy, Sophie J.; Paine, Robert T.; Suchanek, Thomas H.; Sanford, Eric

2016-01-01

Seawater pH and the availability of carbonate ions are decreasing due to anthropogenic carbon dioxide emissions, posing challenges for calcifying marine species. Marine mussels are of particular concern given their role as foundation species worldwide. Here, we document shell growth and calcification patterns in Mytilus californianus, the California mussel, over millennial and decadal scales. By comparing shell thickness across the largest modern shells, the largest mussels collected in the 1960s–1970s and shells from two Native American midden sites (∼1000–2420 years BP), we found that modern shells are thinner overall, thinner per age category and thinner per unit length. Thus, the largest individuals of this species are calcifying less now than in the past. Comparisons of shell thickness in smaller individuals over the past 10–40 years, however, do not show significant shell thinning. Given our sampling strategy, these results are unlikely to simply reflect within-site variability or preservation effects. Review of environmental and biotic drivers known to affect shell calcification suggests declining ocean pH as a likely explanation for the observed shell thinning. Further future decreases in shell thickness could have significant negative impacts on M. californianus survival and, in turn, negatively impact the species-rich complex that occupies mussel beds. PMID:27306049

Historical baselines and the future of shell calcification for a foundation species in a changing ocean

USGS Publications Warehouse

Pfister, Catherine A.; Roy, Kaustuv; Wootton, Timothy J.; McCoy, Sophie J.; Paine, Robert T.; Suchanek, Tom; Sanford, Eric

2016-01-01

Seawater pH and the availability of carbonate ions are decreasing due to anthropogenic carbon dioxide emissions, posing challenges for calcifying marine species. Marine mussels are of particular concern given their role as foundation species worldwide. Here, we document shell growth and calcification patterns in Mytilus californianus, the California mussel, over millennial and decadal scales. By comparing shell thickness across the largest modern shells, the largest mussels collected in the 1960s–1970s and shells from two Native American midden sites (∼1000–2420 years BP), we found that modern shells are thinner overall, thinner per age category and thinner per unit length. Thus, the largest individuals of this species are calcifying less now than in the past. Comparisons of shell thickness in smaller individuals over the past 10–40 years, however, do not show significant shell thinning. Given our sampling strategy, these results are unlikely to simply reflect within-site variability or preservation effects. Review of environmental and biotic drivers known to affect shell calcification suggests declining ocean pH as a likely explanation for the observed shell thinning. Further future decreases in shell thickness could have significant negative impacts on M. californianus survival and, in turn, negatively impact the species-rich complex that occupies mussel beds..

Historical baselines and the future of shell calcification for a foundation species in a changing ocean.

PubMed

Pfister, Catherine A; Roy, Kaustuv; Wootton, J Timothy; McCoy, Sophie J; Paine, Robert T; Suchanek, Thomas H; Sanford, Eric

2016-06-15

Seawater pH and the availability of carbonate ions are decreasing due to anthropogenic carbon dioxide emissions, posing challenges for calcifying marine species. Marine mussels are of particular concern given their role as foundation species worldwide. Here, we document shell growth and calcification patterns in Mytilus californianus, the California mussel, over millennial and decadal scales. By comparing shell thickness across the largest modern shells, the largest mussels collected in the 1960s-1970s and shells from two Native American midden sites (∼1000-2420 years BP), we found that modern shells are thinner overall, thinner per age category and thinner per unit length. Thus, the largest individuals of this species are calcifying less now than in the past. Comparisons of shell thickness in smaller individuals over the past 10-40 years, however, do not show significant shell thinning. Given our sampling strategy, these results are unlikely to simply reflect within-site variability or preservation effects. Review of environmental and biotic drivers known to affect shell calcification suggests declining ocean pH as a likely explanation for the observed shell thinning. Further future decreases in shell thickness could have significant negative impacts on M. californianus survival and, in turn, negatively impact the species-rich complex that occupies mussel beds. © 2016 The Author(s).

Fundamentals, progress, and future directions of nitride-based semiconductors and their composites in two-dimensional limit: A first-principles perspective to recent synthesis

NASA Astrophysics Data System (ADS)

Kecik, D.; Onen, A.; Konuk, M.; Gürbüz, E.; Ersan, F.; Cahangirov, S.; Aktürk, E.; Durgun, E.; Ciraci, S.

2018-03-01

Potential applications of bulk GaN and AlN crystals have made possible single and multilayer allotropes of these III-V compounds to be a focus of interest recently. As of 2005, the theoretical studies have predicted that GaN and AlN can form two-dimensional (2D) stable, single-layer (SL) structures being wide band gap semiconductors and showing electronic and optical properties different from those of their bulk parents. Research on these 2D structures have gained importance with recent experimental studies achieving the growth of ultrathin 2D GaN and AlN on substrates. It is expected that these two materials will open an active field of research like graphene, silicene, and transition metal dichalcogenides. This topical review aims at the evaluation of previous experimental and theoretical works until 2018 in order to provide input for further research attempts in this field. To this end, starting from three-dimensional (3D) GaN and AlN crystals, we review 2D SL and multilayer (ML) structures, which were predicted to be stable in free-standing states. These are planar hexagonal (or honeycomb), tetragonal, and square-octagon structures. First, we discuss earlier results on dynamical and thermal stability of these SL structures, as well as the predicted mechanical properties. Next, their electronic and optical properties with and without the effect of strain are reviewed and compared with those of the 3D parent crystals. The formation of multilayers, hence prediction of new periodic layered structures and also tuning their physical properties with the number of layers are other critical subjects that have been actively studied and discussed here. In particular, an extensive analysis pertaining to the nature of perpendicular interlayer bonds causing planar GaN and AlN to buckle is presented. In view of the fact that SL GaN and AlN can be fabricated only on a substrate, the question of how the properties of free-standing, SL structures are affected if they are grown on a substrate is addressed. We also examine recent works treating the composite structures of GaN and AlN joined commensurately along their zigzag and armchair edges and forming heterostructures, δ-doping, single, and multiple quantum wells, as well as core/shell structures. Finally, outlooks and possible new research directions are briefly discussed.

Subdiffusive exciton transport in quantum dot solids.

PubMed

Akselrod, Gleb M; Prins, Ferry; Poulikakos, Lisa V; Lee, Elizabeth M Y; Weidman, Mark C; Mork, A Jolene; Willard, Adam P; Bulović, Vladimir; Tisdale, William A

2014-06-11

Colloidal quantum dots (QDs) are promising materials for use in solar cells, light-emitting diodes, lasers, and photodetectors, but the mechanism and length of exciton transport in QD materials is not well understood. We use time-resolved optical microscopy to spatially visualize exciton transport in CdSe/ZnCdS core/shell QD assemblies. We find that the exciton diffusion length, which exceeds 30 nm in some cases, can be tuned by adjusting the inorganic shell thickness and organic ligand length, offering a powerful strategy for controlling exciton movement. Moreover, we show experimentally and through kinetic Monte Carlo simulations that exciton diffusion in QD solids does not occur by a random-walk process; instead, energetic disorder within the inhomogeneously broadened ensemble causes the exciton diffusivity to decrease over time. These findings reveal new insights into exciton dynamics in disordered systems and demonstrate the flexibility of QD materials for photonic and optoelectronic applications.

Architected Lattices with High Stiffness and Toughness via Multicore-Shell 3D Printing.

PubMed

Mueller, Jochen; Raney, Jordan R; Shea, Kristina; Lewis, Jennifer A

2018-03-01

The ability to create architected materials that possess both high stiffness and toughness remains an elusive goal, since these properties are often mutually exclusive. Natural materials, such as bone, overcome such limitations by combining different toughening mechanisms across multiple length scales. Here, a new method for creating architected lattices composed of core-shell struts that are both stiff and tough is reported. Specifically, these lattices contain orthotropic struts with flexible epoxy core-brittle epoxy shell motifs in the absence and presence of an elastomeric silicone interfacial layer, which are fabricated by a multicore-shell, 3D printing technique. It is found that architected lattices produced with a flexible core-elastomeric interface-brittle shell motif exhibit both high stiffness and toughness. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Length of Textual Response as a Construct-Irrelevant Response Strategy: The Case of Shell Language. Research Report. ETS RR-13-07

ERIC Educational Resources Information Center

Bejar, Isaac I.; VanWinkle, Waverely; Madnani, Nitin; Lewis, William; Steier, Michael

2013-01-01

The paper applies a natural language computational tool to study a potential construct-irrelevant response strategy, namely the use of "shell language." Although the study is motivated by the impending increase in the volume of scoring of students responses from assessments to be developed in response to the Race to the Top initiative,…

Tomato SlERF.A1, SlERF.B4, SlERF.C3 and SlERF.A3, Members of B3 Group of ERF Family, Are Required for Resistance to Botrytis cinerea

PubMed Central

Ouyang, Zhigang; Liu, Shixia; Huang, Lihong; Hong, Yongbo; Li, Xiaohui; Huang, Lei; Zhang, Yafen; Zhang, Huijuan; Li, Dayong; Song, Fengming

2016-01-01

The Ethylene-Responsive Factors (ERFs) comprise a large family of transcriptional factors that play critical roles in plant immunity. Gray mold disease caused by Botrytis cinerea, a typical necrotrophic fungal pathogen, is the serious disease that threatens tomato production worldwide. However, littler is known about the molecular mechanism regulating the immunity to B. cinerea in tomato. In the present study, virus-induced gene silencing (VIGS)-based functional analyses of 18 members of B3 group (also called Group IX) in tomato ERF family were performed to identify putative ERFs that are involved in disease resistance against B. cinerea. VIGS-based silencing of either SlERF.B1 or SlERF.C2 had lethal effect while silencing of SlERF.A3 (Pit4) significantly suppressed vegetative growth of tomato plants. Importantly, silencing of SlERF.A1, SlERF.A3, SlERF.B4, or SlERF.C3 resulted in increased susceptibility to B. cinerea, attenuated the B. cinerea-induced expression of jasmonic acid/ethylene-mediated signaling responsive defense genes and promoted the B. cinerea-induced H2O2 accumulation. However, silencing of SlERF.A3 also decreased the resistance against Pseudomonas syringae pv. tomato (Pst) DC3000 but silencing of SlERF.A1, SlERF.B4 or SlERF.C3 did not affect the resistance to this bacterial pathogen. Expression of SlERF.A1, SlERF.A3, SlERF.B4, or SlERF.C3 was induced by B. cinerea and by defense signaling hormones such as salicylic acid, methyl jasmonate, and 1-aminocyclopropane-1-carboxylic acid (an ethylene precursor). SlERF.A1, SlERF.B4, SlERF.C3, and SlERF.A3 proteins were found to localize in nucleus of cells and possess transactivation activity in yeasts. These data suggest that SlERF.A1, SlERF.B4, and SlERF.C3, three previously uncharacterized ERFs in B3 group, and SlERF.A3, a previously identified ERF with function in immunity to Pst DC3000, play important roles in resistance against B. cinerea in tomato. PMID:28083004

Seasonal variations of arsenic in mussels Mytilus galloprovincialis

NASA Astrophysics Data System (ADS)

Klarić, Sanja; Pavičić-Hamer, Dijana; Lucu, Čedomil

2004-10-01

Total arsenic concentration in the edible part of mussels Mytilus galloprovincialis was evaluated seasonally in the coastal area of Rijeka Bay (North Adriatic Sea, Croatia). Sampling stations were located close to the City of Bakar with no industrial facilities (site 1), in the vicinity of the oil refinery and oil thermoelectric power plant (Urinj, site 2), and 4 miles away from the Plomin coal thermoelectric power plant (Brseč village, site 3). Additionally, the concentration of arsenic in the tail muscle of the lobster Nephrops norvegicus, collected in Rijeka Bay, was studied. During winter at sites 2 and 3, the total arsenic in the edible part of the mussels was 16.4 mg As/kg FW (FW=fresh weight) and 4.38 mg As/kg FW, respectively, and increased during springtime at site 2 (6.5 mg As/kg FW) compared to the rest of the year, when individual total arsenic concentration at all sites ranged from 1.7 to 3.7 mg As/kg FW. In the winter (sites 2 and 3) and springtime (site 2) there was no correlation between the length of the mussel shell and the arsenic concentration in the edible part of the mussels. In the other seasons, at sites 1, 2 and 3, there was a correlation between arsenic in the edible part of mussels and shell length in most cases (correlation coefficients r varied from 0.64 to 0.85; P <0.05 to P <0.01). Correlation between shell length (in the narrow range of shell lengths from 3.4 to 5.0 cm) and arsenic in the edible part of the mussels shows linearity with a high regression coefficient (r =0.914; P <0.001). The increase of arsenic in the mussels during winter and spring was suggested at least partially as a result of a low nutritional status, i.e. reduced weight of the mussels' edible part during winter. In addition, a linear relationship was found between body length and arsenic concentration in the tail muscle (mean 17.11±4.48 mg As/kg FW) of the Norway lobster.

49 CFR Appendix B to Part 229 - Schedule of Civil Penalties 1

Code of Federal Regulations, 2011 CFR

2011-10-01

... 229.73Wheel sets 2,500 5,000 229.75Wheel and tire defects: (a),(d) Slid flat or shelled spot(s): (1) One spot 21/2″ or more but less than 3″ in length 2,500 5,000 (2) One spot 3″ or more in length 5,000 7,500 (3) Two adjoining spots each of which is 2″ or more in length but less than 21/2″ in length 2...

49 CFR Appendix B to Part 229 - Schedule of Civil Penalties 1

Code of Federal Regulations, 2010 CFR

2010-10-01

... 229.73Wheel sets 2,500 5,000 229.75Wheel and tire defects: (a),(d) Slid flat or shelled spot(s): (1) One spot 21/2″ or more but less than 3″ in length 2,500 5,000 (2) One spot 3″ or more in length 5,000 7,500 (3) Two adjoining spots each of which is 2″ or more in length but less than 21/2″ in length 2...

Dehydration-induced tps gene transcripts from an anhydrobiotic nematode contain novel spliced leaders and encode atypical GT-20 family proteins.

PubMed

Goyal, K; Browne, J A; Burnell, A M; Tunnacliffe, A

2005-06-01

Accumulation of the non-reducing disaccharide trehalose is associated with desiccation tolerance during anhydrobiosis in a number of invertebrates, but there is little information on trehalose biosynthetic genes in these organisms. We have identified two trehalose-6-phosphate synthase (tps) genes in the anhydrobiotic nematode Aphelenchus avenae and determined full length cDNA sequences for both; for comparison, full length tps cDNAs from the model nematode, Caenorhabditis elegans, have also been obtained. The A. avenae genes encode very similar proteins containing the catalytic domain characteristic of the GT-20 family of glycosyltransferases and are most similar to tps-2 of C. elegans; no evidence was found for a gene in A. avenae corresponding to Ce-tps-1. Analysis of A. avenae tps cDNAs revealed several features of interest, including alternative trans-splicing of spliced leader sequences in Aav-tps-1, and four different, novel SL1-related trans-spliced leaders, which were different to the canonical SL1 sequence found in all other nematodes studied. The latter observation suggests that A. avenae does not comply with the strict evolutionary conservation of SL1 sequences observed in other species. Unusual features were also noted in predicted nematode TPS proteins, which distinguish them from homologues in other higher eukaryotes (plants and insects) and in micro-organisms. Phylogenetic analysis confirmed their membership of the GT-20 glycosyltransferase family, but indicated an accelerated rate of molecular evolution. Furthermore, nematode TPS proteins possess N- and C-terminal domains, which are unrelated to those of other eukaryotes: nematode C-terminal domains, for example, do not contain trehalose-6-phosphate phosphatase-like sequences, as seen in plant and insect homologues. During onset of anhydrobiosis, both tps genes in A. avenae are upregulated, but exposure to cold or increased osmolarity also results in gene induction, although to a lesser extent. Trehalose seems likely therefore to play a role in a number of stress responses in nematodes.

New latent heat storage system with nanoparticles for thermal management of electric vehicles

NASA Astrophysics Data System (ADS)

Javani, N.; Dincer, I.; Naterer, G. F.

2014-12-01

In this paper, a new passive thermal management system for electric vehicles is developed. A latent heat thermal energy storage with nanoparticles is designed and optimized. A genetic algorithm method is employed to minimize the length of the heat exchanger tubes. The results show that even the optimum length of a shell and tube heat exchanger becomes too large to be employed in a vehicle. This is mainly due to the very low thermal conductivity of phase change material (PCM) which fills the shell side of the heat exchanger. A carbon nanotube (CNT) and PCM mixture is then studied where the probability of nanotubes in a series configuration is defined as a deterministic design parameter. Various heat transfer rates, ranging from 300 W to 600 W, are utilized to optimize battery cooling options in the heat exchanger. The optimization results show that smaller tube diameters minimize the heat exchanger length. Furthermore, finned tubes lead to a higher heat exchanger length due to more heat transfer resistance. By increasing the CNT concentration, the optimum length of the heat exchanger decreases and makes the improved thermal management system a more efficient and competitive with air and liquid thermal management systems.

Altered myofilament structure and function in dogs with Duchenne muscular dystrophy cardiomyopathy

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

Ait Mou, Younss; Lacampagne, Alain; Irving, Thomas

Aim Duchenne Muscular Dystrophy (DMD) is associated with progressive depressed left ventricular (LV) function. However, DMD effects on myofilament structure and function are poorly understood. Golden Retriever Muscular Dystrophy (GRMD) is a dog model of DMD recapitulating the human form of DMD. Objective The objective of this study is to evaluate myofilament structure and function alterations in GRMD model with spontaneous cardiac failure. Methods and results We have employed synchrotron X-rays diffraction to evaluate myofilament lattice spacing at various sarcomere lengths (SL) on permeabilized LV myocardium. We found a negative correlation between SL and lattice spacing in both sub-epicardium (EPI)more » and sub-endocardium (ENDO) LV layers in control dog hearts. In the ENDO of GRMD hearts this correlation is steeper due to higher lattice spacing at short SL (1.9 μm). Furthermore, cross-bridge cycling indexed by the kinetics of tension redevelopment (ktr) was faster in ENDO GRMD myofilaments at short SL. We measured post-translational modifications of key regulatory contractile proteins. S-glutathionylation of cardiac Myosin Binding Protein-C (cMyBP-C) was unchanged and PKA dependent phosphorylation of the cMyBP-C was significantly reduced in GRMD ENDO tissue and more modestly in EPI tissue. Conclusions We found a gradient of contractility in control dogs' myocardium that spreads across the LV wall, negatively correlated with myofilament lattice spacing. Chronic stress induced by dystrophin deficiency leads to heart failure that is tightly associated with regional structural changes indexed by increased myofilament lattice spacing, reduced phosphorylation of regulatory proteins and altered myofilament contractile properties in GRMD dogs.« less

Stalk-dependent and Stalk-independent Signaling by the Adhesion G Protein-coupled Receptors GPR56 (ADGRG1) and BAI1 (ADGRB1).

PubMed

Kishore, Ayush; Purcell, Ryan H; Nassiri-Toosi, Zahra; Hall, Randy A

2016-02-12

The adhesion G protein-coupled receptors (aGPCRs) are a large yet poorly understood family of seven-transmembrane proteins. A defining characteristic of the aGPCR family is the conserved GAIN domain, which has autoproteolytic activity and can cleave the receptors near the first transmembrane domain. Several aGPCRs, including ADGRB1 (BAI1 or B1) and ADGRG1 (GPR56 or G1), have been found to exhibit significantly increased constitutive activity when truncated to mimic GAIN domain cleavage (ΔNT). Recent reports have suggested that the new N-terminal stalk, which is revealed by GAIN domain cleavage, can directly activate aGPCRs as a tethered agonist. We tested this hypothesis in studies on two distinct aGPCRs, B1 and G1, by engineering mutant receptors lacking the entire NT including the stalk (B1- and G1-SL, with "SL" indicating "stalkless"). These receptors were evaluated in a battery of signaling assays and compared with full-length wild-type and cleavage-mimicking (ΔNT) forms of the two receptors. We found that B1-SL, in multiple assays, exhibited robust signaling activity, suggesting that the membrane-proximal stalk region is not necessary for its activation. For G1, however, the results were mixed, with the SL mutant exhibiting robust activity in several signaling assays (including TGFα shedding, activation of NFAT luciferase, and β-arrestin recruitment) but reduced activity relative to ΔNT in a distinct assay (activation of SRF luciferase). These data support a model in which the activation of certain pathways downstream of aGPCRs is stalk-dependent, whereas signaling to other pathways is stalk-independent. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Chaperonin-containing T-complex Protein 1 Subunit ζ Serves as an Autoantigen Recognized by Human Vδ2 γδ T Cells in Autoimmune Diseases.

PubMed

Chen, Hui; You, Hongqin; Wang, Lifang; Zhang, Xuan; Zhang, Jianmin; He, Wei

2016-09-16

Human γδ T cells recognize conserved endogenous and stress-induced antigens typically associated with autoimmune diseases. However, the role of γδ T cells in autoimmune diseases is not clear. Few autoimmune disease-related antigens recognized by T cell receptor (TCR) γδ have been defined. In this study, we compared Vδ2 TCR complementarity-determining region 3 (CDR3) between systemic lupus erythematosus (SLE) patients and healthy donors. Results show that CDR3 length distribution differed significantly and displayed oligoclonal characteristics in SLE patients when compared with healthy donors. We found no difference in the frequency of Jδ gene fragment usage between these two groups. According to the dominant CDR3δ sequences in SLE patients, synthesized SL2 peptides specifically bound to human renal proximal tubular epithelial cell line HK-2; SL2-Vm, a mutant V sequence of SL2, did not bind. We identified the putative protein ligand chaperonin-containing T-complex protein 1 subunit ζ (CCT6A) using SL2 as a probe in HK-2 cell protein extracts by affinity chromatography and liquid chromatography-electrospray ionization-tandem mass spectrometry analysis. We found CCT6A expression on the surface of HK-2 cells. Cytotoxicity of only Vδ2 γδ T cells to HK-2 cells was blocked by anti-CCT6A antibody. Finally, we note that CCT6A concentration was significantly increased in plasma of SLE and rheumatoid arthritis patients. These data suggest that CCT6A is a novel autoantigen recognized by Vδ2 γδ T cells, which deepens our understanding of mechanisms in autoimmune diseases. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Auditory observation of stepping actions can cue both spatial and temporal components of gait in Parkinson׳s disease patients.

PubMed

Young, William R; Rodger, Matthew W M; Craig, Cathy M

2014-05-01

A common behavioural symptom of Parkinson׳s disease (PD) is reduced step length (SL). Whilst sensory cueing strategies can be effective in increasing SL and reducing gait variability, current cueing strategies conveying spatial or temporal information are generally confined to the use of either visual or auditory cue modalities, respectively. We describe a novel cueing strategy using ecologically-valid 'action-related' sounds (footsteps on gravel) that convey both spatial and temporal parameters of a specific action within a single cue. The current study used a real-time imitation task to examine whether PD affects the ability to re-enact changes in spatial characteristics of stepping actions, based solely on auditory information. In a second experimental session, these procedures were repeated using synthesized sounds derived from recordings of the kinetic interactions between the foot and walking surface. A third experimental session examined whether adaptations observed when participants walked to action-sounds were preserved when participants imagined either real recorded or synthesized sounds. Whilst healthy control participants were able to re-enact significant changes in SL in all cue conditions, these adaptations, in conjunction with reduced variability of SL were only observed in the PD group when walking to, or imagining the recorded sounds. The findings show that while recordings of stepping sounds convey action information to allow PD patients to re-enact and imagine spatial characteristics of gait, synthesis of sounds purely from gait kinetics is insufficient to evoke similar changes in behaviour, perhaps indicating that PD patients have a higher threshold to cue sensorimotor resonant responses. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Mail-Order Microfluidics: Evaluation of Stereolithography for the Production of Microfluidic Devices

PubMed Central

Au, Anthony K.; Lee, Wonjae; Folch, Albert

2015-01-01

The vast majority of microfluidic devices are developed in PDMS by molding (“soft lithography”) because PDMS is an inexpensive material, has physicochemical properties that are well suited for biomedical and physical sciences applications, and design cycle lengths are generally adequate for prototype development. However, PDMS molding is tediously slow and thus cannot provide the high- or medium-volume production required for the commercialization of devices. While high-throughput plastic molding techniques (e.g. injection molding) exist, the exorbitant cost of the molds and/or the equipment can be a serious obstacle for device commercialization, especially for small startups. High-volume production is not required to reach niche markets such as clinical trials, biomedical research supplies, customized research equipment, and classroom projects. Crucially, both PDMS and plastic molding are layer-by-layer techniques where each layer is produced as a result of physicochemical processes not specified in the initial photomask(s) and where the final device requires assembly by bonding, all resulting in a cost that is very hard to predict at the start of the project. By contrast, stereolithography (SL) is an automated fabrication technique that allows for the production of quasi-arbitrary 3D shapes in a single polymeric material at medium-volume throughputs (ranging from a single part to hundreds of parts). Importantly, SL devices can be designed between several groups using CAD tools, conveniently ordered by mail, and their cost precisely predicted via a web interface. Here we evaluate the resolution of an SL mail-order service and the main causes of resolution loss; the optical clarity of the devices and how to address the lack of clarity for imaging in the channels; and the future role that SL could play in the commercialization of microfluidic devices. PMID:24510161

Mail-order microfluidics: evaluation of stereolithography for the production of microfluidic devices.

PubMed

Au, Anthony K; Lee, Wonjae; Folch, Albert

2014-04-07

The vast majority of microfluidic devices are developed in PDMS by molding ("soft lithography") because PDMS is an inexpensive material, has physicochemical properties that are well suited for biomedical and physical sciences applications, and design cycle lengths are generally adequate for prototype development. However, PDMS molding is tediously slow and thus cannot provide the high- or medium-volume production required for the commercialization of devices. While high-throughput plastic molding techniques (e.g. injection molding) exist, the exorbitant cost of the molds and/or the equipment can be a serious obstacle for device commercialization, especially for small startups. High-volume production is not required to reach niche markets such as clinical trials, biomedical research supplies, customized research equipment, and classroom projects. Crucially, both PDMS and plastic molding are layer-by-layer techniques where each layer is produced as a result of physicochemical processes not specified in the initial photomask(s) and where the final device requires assembly by bonding, all resulting in a cost that is very hard to predict at the start of the project. By contrast, stereolithography (SL) is an automated fabrication technique that allows for the production of quasi-arbitrary 3D shapes in a single polymeric material at medium-volume throughputs (ranging from a single part to hundreds of parts). Importantly, SL devices can be designed between several groups using CAD tools, conveniently ordered by mail, and their cost precisely predicted via a web interface. Here we evaluate the resolution of an SL mail-order service and the main causes of resolution loss; the optical clarity of the devices and how to address the lack of clarity for imaging in the channels; and the future role that SL could play in the commercialization of microfluidic devices.

Silencing of the tomato phosphatidylinositol-phospholipase C2 (SlPLC2) reduces plant susceptibility to Botrytis cinerea.

PubMed

Gonorazky, Gabriela; Guzzo, María Carla; Abd-El-Haliem, Ahmed M; Joosten, Matthieu H A J; Laxalt, Ana María

2016-12-01

The tomato [Solanum lycopersicum (Sl)] phosphatidylinositol-phospholipase C (PI-PLC) gene family is composed of six members, named SlPLC1 to SlPLC6, differentially regulated on pathogen attack. We have previously shown that the fungal elicitor xylanase induces a raise of SlPLC2 and SlPLC5 transcripts and that SlPLC2, but not SlPLC5, is required for xylanase-induced expression of defense-related genes. In this work we studied the role of SlPLC2 in the interaction between tomato and the necrotrophic fungus Botrytis cinerea. Inoculation of tomato leaves with B. cinerea increases SlPLC2 transcript levels. We knocked-down the expression of SlPLC2 by virus-induced gene silencing and plant defense responses were analyzed upon B. cinerea inoculation. SlPLC2 silenced plants developed smaller necrotic lesions concomitantly with less proliferation of the fungus. Silencing of SlPLC2 resulted as well in a reduced production of reactive oxygen species. Upon B. cinerea inoculation, transcript levels of the salicylic acid (SA)-defense pathway marker gene SlPR1a were diminished in SlPLC2 silenced plants compared to non-silenced infected plants, while transcripts of the jasmonic acid (JA)-defense gene markers Proteinase Inhibitor I and II (SlPI-I and SlPI-II) were increased. This implies that SlPLC2 participates in plant susceptibility to B. cinerea. © 2016 BSPP and John Wiley & Sons Ltd.

Laboratory investigations of the effects of predator sex and size on prey selection by the Asian crab, Hemigrapsus sanguineus.

PubMed

Brousseau, D J.; Filipowicz, A; Baglivo, J A.

2001-07-30

Laboratory studies have shown that the nonindigenous Asian shore crab, Hemigrapsus sanguineus, readily consumes three species of commercial bivalves: blue mussels, Mytilus edulis, soft-shell clams, Mya arenaria, and oysters, Crassostrea virginica. Although crabs can eat bivalves of a wide size range, they preferred the smaller prey (

ALLOMETRIC LENGTH-WEIGHT RELATIONSHIPS FOR BENTHIC PREY OF AQUATIC WILDLIFE IN COASTAL MARINE HABITATS

EPA Science Inventory

We developed models to estimate the soft tissue content of benthic marine invertebrates that are prey for aquatic wildlife. Allometric regression models of tissue wet weight with shell length for 10 species of benthic invertebrates had r2 values ranging from 0.29 for hermit crabs...

Nano-engineering of three-dimensional core/shell nanotube arrays for high performance supercapacitors

NASA Astrophysics Data System (ADS)

Grote, Fabian; Wen, Liaoyong; Lei, Yong

2014-06-01

Large-scale arrays of core/shell nanostructures are highly desirable to enhance the performance of supercapacitors. Here we demonstrate an innovative template-based fabrication technique with high structural controllability, which is capable of synthesizing well-ordered three-dimensional arrays of SnO2/MnO2 core/shell nanotubes for electrochemical energy storage in supercapacitor applications. The SnO2 core is fabricated by atomic layer deposition and provides a highly electrical conductive matrix. Subsequently a thin MnO2 shell is coated by electrochemical deposition onto the SnO2 core, which guarantees a short ion diffusion length within the shell. The core/shell structure shows an excellent electrochemical performance with a high specific capacitance of 910 F g-1 at 1 A g-1 and a good rate capability of remaining 217 F g-1 at 50 A g-1. These results shall pave the way to realize aqueous based asymmetric supercapacitors with high specific power and high specific energy.

Tailoring surface plasmon resonance and dipole cavity plasmon modes of scattering cross section spectra on the single solid-gold/gold-shell nanorod

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

Chou Chau, Yuan-Fong, E-mail: chou.fong@ubd.edu.bn; Lim, Chee Ming; Kumara, N. T. R. N.

Tunable surface plasmon resonance (SPR) and dipole cavity plasmon modes of the scattering cross section (SCS) spectra on the single solid-gold/gold-shell nanorod have been numerically investigated by using the finite element method. Various effects, such as the influence of SCS spectra under x- and y-polarizations on the surface of the single solid-gold/gold-shell nanorod, are discussed in detail. With the single gold-shell nanorod, one can independently tune the relative SCS spectrum width by controlling the rod length and rod diameter, and the surface scattering by varying the shell thickness and polarization direction, as well as the dipole peak energy. These behaviorsmore » are consistent with the properties of localized SPRs and offer a way to optically control and produce selected emission wavelengths from the single solid-gold/gold-shell nanorod. The electric field and magnetic distributions provide us a qualitative idea of the geometrical properties of the single solid-gold/gold-shell nanorod on plasmon resonance.« less

Iceberg Scour and Shell Damage in the Antarctic Bivalve Laternula elliptica

PubMed Central

Harper, Elizabeth M.; Clark, Melody S.; Hoffman, Joseph I.; Philipp, Eva E. R.; Peck, Lloyd S.; Morley, Simon A.

2012-01-01

We document differences in shell damage and shell thickness in a bivalve mollusc (Laternula elliptica) from seven sites around Antarctica with differing exposures to ice movement. These range from 60% of the sea bed impacted by ice per year (Hangar Cove, Antarctic Peninsula) to those protected by virtually permanent sea ice cover (McMurdo Sound). Patterns of shell damage consistent with blunt force trauma were observed in populations where ice scour frequently occurs; damage repair frequencies and the thickness of shells correlated positively with the frequency of iceberg scour at the different sites with the highest repair rates and thicker shells at Hangar Cove (74.2% of animals damaged) compared to the other less impacted sites (less than 10% at McMurdo Sound). Genetic analysis of population structure using Amplified Fragment Length Polymorphisms (AFLPs) revealed no genetic differences between the two sites showing the greatest difference in shell morphology and repair rates. Taken together, our results suggest that L. elliptica exhibits considerable phenotypic plasticity in response to geographic variation in physical disturbance. PMID:23029484

Tailoring surface plasmon resonance and dipole cavity plasmon modes of scattering cross section spectra on the single solid-gold/gold-shell nanorod

NASA Astrophysics Data System (ADS)

Chou Chau, Yuan-Fong; Lim, Chee Ming; Lee, Chuanyo; Huang, Hung Ji; Lin, Chun-Ting; Kumara, N. T. R. N.; Yoong, Voo Nyuk; Chiang, Hai-Pang

2016-09-01

Tunable surface plasmon resonance (SPR) and dipole cavity plasmon modes of the scattering cross section (SCS) spectra on the single solid-gold/gold-shell nanorod have been numerically investigated by using the finite element method. Various effects, such as the influence of SCS spectra under x- and y-polarizations on the surface of the single solid-gold/gold-shell nanorod, are discussed in detail. With the single gold-shell nanorod, one can independently tune the relative SCS spectrum width by controlling the rod length and rod diameter, and the surface scattering by varying the shell thickness and polarization direction, as well as the dipole peak energy. These behaviors are consistent with the properties of localized SPRs and offer a way to optically control and produce selected emission wavelengths from the single solid-gold/gold-shell nanorod. The electric field and magnetic distributions provide us a qualitative idea of the geometrical properties of the single solid-gold/gold-shell nanorod on plasmon resonance.

Association of myostatin variants with growth traits of Zhikong scallop ( Chlamys farreri)

NASA Astrophysics Data System (ADS)

Fu, Qiang; Guo, Huihui; Feng, Liying; Li, Xue; Zhang, Lingling; Wang, Shi; Hu, Xiaoli; Bao, Zhenmin

2016-02-01

Scallop is a popular sea food and an important aquaculture shellfish. Identification of genes and genetic variants relating to scallop growth could benefit high-yielding scallop breeding. Myostatin ( MSTN) is a conservative regulator of muscle growth, and has become one of the most important target genes for genetic improvement of the production of farmed animals. In this study, four single nucleotide polymorphisms (SNPs) were identified in the 5' flanking region of MSTN gene ( CfMSTN) in Zhikong scallop ( Chlamys farreri). The association of these SNPs with scallop growth traits, including shell length, shell height, body weight and striated muscle weight was analyzed. The SNP g-1162G

Plasma Membrane Intrinsic Proteins SlPIP2;1, SlPIP2;7 and SlPIP2;5 Conferring Enhanced Drought Stress Tolerance in Tomato.

PubMed

Li, Ren; Wang, Jinfang; Li, Shuangtao; Zhang, Lei; Qi, Chuandong; Weeda, Sarah; Zhao, Bing; Ren, Shuxin; Guo, Yang-Dong

2016-08-22

The function of aquaporin (AQP) protein in transporting water is crucial for plants to survive in drought stress. With 47 homologues in tomato (Solanum lycopersicum) were reported, but the individual and integrated functions of aquaporins involved in drought response remains unclear. Here, three plasma membrane intrinsic protein genes, SlPIP2;1, SlPIP2;7 and SlPIP2;5, were identified as candidate aquaporins genes because of highly expressed in tomato roots. Assay on expression in Xenopus oocytes demonstrated that SlPIP2s protein displayed water channel activity and facilitated water transport into the cells. With real-time PCR and in situ hybridization analysis, SlPIP2s were considered to be involved in response to drought treatment. To test its function, transgenic Arabidopsis and tomato lines overexpressing SlPIP2;1, SlPIP2;7 or SlPIP2;5 were generated. Compared with wild type, the over-expression of SlPIP2;1, SlPIP2;7 or SlPIP2;5 transgenic Arabidopsis and tomato plants all showed significantly higher hydraulic conductivity levels and survival rates under both normal and drought conditions. Taken together, this study concludes that aquaporins (SlPIP2;1, SlPIP2;7 and SlPIP2;5) contribute substantially to root water uptake in tomato plants through improving plant water content and maintaining osmotic balance.

Dynamic equations for an isotropic spherical shell using the power series method and surface differential operators

NASA Astrophysics Data System (ADS)

Okhovat, Reza; Boström, Anders

2017-04-01

Dynamic equations for an isotropic spherical shell are derived by using a series expansion technique. The displacement field is split into a scalar (radial) part and a vector (tangential) part. Surface differential operators are introduced to decrease the length of all equations. The starting point is a power series expansion of the displacement components in the thickness coordinate relative to the mid-surface of the shell. By using the expansions of the displacement components, the three-dimensional elastodynamic equations yield a set of recursion relations among the expansion functions that can be used to eliminate all but the four of lowest order and to express higher order expansion functions in terms of those of lowest orders. Applying the boundary conditions on the surfaces of the spherical shell and eliminating all but the four lowest order expansion functions give the shell equations as a power series in the shell thickness. After lengthy manipulations, the final four shell equations are obtained in a relatively compact form which are given to second order in shell thickness explicitly. The eigenfrequencies are compared to exact three-dimensional theory with excellent agreement and to membrane theory.

SlNCED1 and SlCYP707A2: key genes involved in ABA metabolism during tomato fruit ripening

PubMed Central

Ji, Kai; Kai, Wenbin; Zhao, Bo; Sun, Yufei; Yuan, Bing; Dai, Shengjie; Li, Qian; Chen, Pei; Wang, Ya; Pei, Yuelin; Wang, Hongqing; Guo, Yangdong; Leng, Ping

2014-01-01

Abscisic acid (ABA) plays an important role in fruit development and ripening. Here, three NCED genes encoding 9-cis-epoxycarotenoid dioxygenase (NCED, a key enzyme in the ABA biosynthetic pathway) and three CYP707A genes encoding ABA 8′-hydroxylase (a key enzyme in the oxidative catabolism of ABA) were identified in tomato fruit by tobacco rattle virus-induced gene silencing (VIGS). Quantitative real-time PCR showed that VIGS-treated tomato fruits had significant reductions in target gene transcripts. In SlNCED1-RNAi-treated fruits, ripening slowed down, and the entire fruit turned to orange instead of red as in the control. In comparison, the downregulation of SlCYP707A2 expression in SlCYP707A2-silenced fruit could promote ripening; for example, colouring was quicker than in the control. Silencing SlNCED2/3 or SlCYP707A1/3 made no significant difference to fruit ripening comparing RNAi-treated fruits with control fruits. ABA accumulation and SlNCED1transcript levels in the SlNCED1-RNAi-treated fruit were downregulated to 21% and 19% of those in control fruit, respectively, but upregulated in SlCYP707A2-RNAi-treated fruit. Silencing SlNCED1 or SlCYP707A2 by VIGS significantly altered the transcripts of a set of both ABA-responsive and ripening-related genes, including ABA-signalling genes (PYL1, PP2C1, and SnRK2.2), lycopene-synthesis genes (SlBcyc, SlPSY1 and SlPDS), and cell wall-degrading genes (SlPG1, SlEXP, and SlXET) during ripening. These data indicate that SlNCED1 and SlCYP707A2 are key genes in the regulation of ABA synthesis and catabolism, and are involved in fruit ripening as positive and negative regulators, respectively. PMID:25039074

Quantification of tomato and Arabidopsis mobile RNAs trafficking into the parasitic plant Cuscuta pentagona.

PubMed

LeBlanc, Megan; Kim, Gunjune; Patel, Beneeta; Stromberg, Verlyn; Westwood, James

2013-12-01

The cross-species movement of mRNA from hosts to the parasitic plant Cuscuta pentagona has been reported previously, but has not been characterized quantitatively or with attention to uptake patterns and the fate of specific mRNAs. Real-time PCR and RNA-Seq approaches were used to identify and characterize mobile transcripts from tomato and Arabidopsis hosts into C. pentagona. Tomato transcripts of Gibberellic Acid Insensitive (SlGAI) and Cathepsin D Proteinase Inhibitor (SlPI) differed significantly in the rate of uptake into the parasite, but were then distributed over the length of the parasite shoot. When parasite shoots were detached from the hosts, the SlPI transcript concentrations in the parasite showed the greatest decrease within the first 8 h. Arabidopsis transcripts also varied in mobility into the parasite, and assay of specific regions of a Salt-inducible Zinc Finger Protein (AtSZF1) transcript revealed distinct patterns of abundance in the parasite. The uptake and distribution of host mRNAs into C. pentagona appears to vary among mRNAs, and perhaps even with the region of the mRNA under investigation. We propose that mRNAs traffic into the parasite via multiple routes, or that other mechanisms for selective uptake and mobility exist between host and parasite. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

RNAi-Mediated Knockdown of Catalase Causes Cell Cycle Arrest in SL-1 Cells and Results in Low Survival Rate of Spodoptera litura (Fabricius)

PubMed Central

Hu, Meiying; Chen, Shaohua; Muhammad, Rizwan-ul-Haq; Dong, Xiaolin; Gong, Liang

2013-01-01

Deregulated reactive oxygen species (ROS) production can lead to the disruption of structural and functional integrity of cells as a consequence of reactive interaction between ROS and various biological components. Catalase (CAT) is a common enzyme existing in nearly all organisms exposed to oxygen, which decomposes harmful hydrogen peroxide, into water and oxygen. In this study, the full length sequence that encodes CAT-like protein from Spodoptera litura named siltCAT (GenBank accession number: JQ_663444) was cloned and characterized. Amino acid sequence alignment showed siltCAT shared relatively high conservation with other insect, especially the conserved residues which defined heme and NADPH orientation. Expression pattern analysis showed that siltCAT mRNA was mainly expressed in the fat body, midgut, cuticle and malpighian tube, and as well as over last instar larvae, pupa and adult stages. RNA interference was used to silence CAT gene in SL-1 cells and the fourth-instar stage of S. litura larvae respectively. Our results provided evidence that CAT knockdown induced ROS generation, cell cycle arrest and apoptosis in SL-1 cells. It also confirmed the decrease in survival rate because of increased ROS production in experimental groups injected with double-stranded RNA of CAT (dsCAT). This study implied that ROS scavenging by CAT is important for S. litura survival. PMID:23555693

Familial Hypertrophic Cardiomyopathy Related Cardiac Troponin C L29Q Mutation Alters Length-Dependent Activation and Functional Effects of Phosphomimetic Troponin I*

PubMed Central

Li, Alison Y.; Stevens, Charles M.; Liang, Bo; Rayani, Kaveh; Little, Sean; Davis, Jonathan; Tibbits, Glen F.

2013-01-01

The Ca2+ binding properties of the FHC-associated cardiac troponin C (cTnC) mutation L29Q were examined in isolated cTnC, troponin complexes, reconstituted thin filament preparations, and skinned cardiomyocytes. While higher Ca2+ binding affinity was apparent for the L29Q mutant in isolated cTnC, this phenomenon was not observed in the cTn complex. At the level of the thin filament in the presence of phosphomimetic TnI, L29Q cTnC further reduced the Ca2+ affinity by 27% in the steady-state measurement and increased the Ca2+ dissociation rate by 20% in the kinetic studies. Molecular dynamics simulations suggest that L29Q destabilizes the conformation of cNTnC in the presence of phosphomimetic cTnI and potentially modulates the Ca2+ sensitivity due to the changes of the opening/closing equilibrium of cNTnC. In the skinned cardiomyocyte preparation, L29Q cTnC increased Ca2+ sensitivity in a highly sarcomere length (SL)-dependent manner. The well-established reduction of Ca2+ sensitivity by phosphomimetic cTnI was diminished by 68% in the presence of the mutation and it also depressed the SL-dependent increase in myofilament Ca2+ sensitivity. This might result from its modified interaction with cTnI which altered the feedback effects of cross-bridges on the L29Q cTnC-cTnI-Tm complex. This study demonstrates that the L29Q mutation alters the contractility and the functional effects of the phosphomimetic cTnI in both thin filament and single skinned cardiomyocytes and importantly that this effect is highly sarcomere length dependent. PMID:24260207

[Turbinella angulata and Busyconperversum (Mesogasteropoda: Turbinellidae and Melongenidae) population and reproductive dynamics in the Campeche Bank, Mexico].

PubMed

Valencia, Josefina Santos; Díaz, Martha Enríquez; Aranda, Dalila Aldana

2013-03-01

Turbinella angulata and Busycon perversum are two marine gastropods that support the 90% of conch fisheries in the Gulf of Mexico, nevertheless there is no information available to support a management strategy for both species. The aim of this work was to obtain preliminary fishery information to promote management actions for both species in the Campeche Bank. The population of conchs was sampled in 12 transects (150x1.5m) by SCUBA diving from April 2008 to March 2010. All conchs were collected and siphonal length (SL) was measured. These samples were complemented with data from the commercial catches, analyzing a total of 2 832 individuals of T angulata. Siphonal length varied between 63 and 282mm. Sex ratio was of 0.98:1 female:male. The von Bertalanffy growth equation parameters were: L infinity =346mm; K=0.30 and t(0)=-0.24. Spawning extended from January to May with a long resting stage from June to September for over 80% of the adult population. The first gonadic maturity (L50) was at 210mm (SL) for females and 200mm for males. For B. perversum a total of 1655 individuals were analyzed. Siphonal length varied between 78 and 291mm with significant differences between male and female (p<0.05). Sex ratio was of 1:0.25 female:male. The growth parameters obtained were: Linifinity=360mm; K=0.35 and t(0)=-0.19. The spawning period was from August to December with resting stage from January to April. The L50 was 215mm (LS) for females and 190mm for males. Both species presented one recruitment pulse. These results will be useful to design management schemes based on population dynamics and reproductive attributes.

Natural synergism of acid and lactone type mixed sophorolipids in interfacial activities and cytotoxicities.

PubMed

Hirata, Yoshihiko; Ryu, Mizuyuki; Igarashi, Keisuke; Nagatsuka, Asami; Furuta, Taro; Kanaya, Shigenori; Sugiura, Masaki

2009-01-01

Sophorolipids (SLs) naturally produced from Candida bombicola are a mixture of lactonic (SL-lactone) and acidic (SL-acid) sophorosides of 17-L-hydroxydecanoic acid with an SL-lactone:SL-acid ratio of 72:28. SLs are biodegradable low-foaming surfactants with high detergency and hardness-tolerance properties. To analyze the effect of the SL-lactone:SL-acid ratio on these properties, SL-LXs containing X% SL-lactone, in which X varied from 0 to 100, were prepared and their interfacial activities and cytotoxicities examined. The minimum surface tension values for all SLs examined were comparable. The critical micelle concentration (CMC) was 680 mg/L for SL-L0 and 62-110 mg/L for the other SLs. Interestingly, natural SL (SL-L72) had the lowest surface tension and CMC among all of the SLs examined. The foaming ability and stability of the SLs were dependent on the SL-L content. SL-L0 and L17 had higher foaming values than the other SLs examined in 0-ppm hardness water. These values greatly reduced and became constant when the SL-L content increased over 55%. The detergencies of all of the SLs examined were comparable, except for those of SL-L0 and SL-L100, which were slightly lower than those of the other SLs. These results suggest that natural synergism between SLs creates a better balance for many interfacial activities. The cytotoxicity of SL-L72 was higher than that of SL-L0, but was comparable to that of surfactin, which is commercially available for cosmetic use. The low cytotoxicities and high interfacial properties of SLs increase their usefulness as biocompatible surface active agents for many applications.

An embedding of the universal Askey-Wilson algebra into Uq (sl2) ⊗Uq (sl2) ⊗Uq (sl2)

NASA Astrophysics Data System (ADS)

Huang, Hau-Wen

2017-09-01

The Askey-Wilson algebras were used to interpret the algebraic structure hidden in the Racah-Wigner coefficients of the quantum algebra Uq (sl2). In this paper, we display an injection of a universal analog △q of Askey-Wilson algebras into Uq (sl2) ⊗Uq (sl2) ⊗Uq (sl2) behind the application. Moreover we establish the decomposition rules for 3-fold tensor products of irreducible Verma Uq (sl2)-modules and of finite-dimensional irreducible Uq (sl2)-modules into the direct sums of finite-dimensional irreducible △q-modules. As an application, we derive a formula for the Racah-Wigner coefficients of Uq (sl2).

Systematic discovery of mutation-specific synthetic lethals by mining pan-cancer human primary tumor data

NASA Astrophysics Data System (ADS)

Sinha, Subarna; Thomas, Daniel; Chan, Steven; Gao, Yang; Brunen, Diede; Torabi, Damoun; Reinisch, Andreas; Hernandez, David; Chan, Andy; Rankin, Erinn B.; Bernards, Rene; Majeti, Ravindra; Dill, David L.

2017-05-01

Two genes are synthetically lethal (SL) when defects in both are lethal to a cell but a single defect is non-lethal. SL partners of cancer mutations are of great interest as pharmacological targets; however, identifying them by cell line-based methods is challenging. Here we develop MiSL (Mining Synthetic Lethals), an algorithm that mines pan-cancer human primary tumour data to identify mutation-specific SL partners for specific cancers. We apply MiSL to 12 different cancers and predict 145,891 SL partners for 3,120 mutations, including known mutation-specific SL partners. Comparisons with functional screens show that MiSL predictions are enriched for SLs in multiple cancers. We extensively validate a SL interaction identified by MiSL between the IDH1 mutation and ACACA in leukaemia using gene targeting and patient-derived xenografts. Furthermore, we apply MiSL to pinpoint genetic biomarkers for drug sensitivity. These results demonstrate that MiSL can accelerate precision oncology by identifying mutation-specific targets and biomarkers.

D Central Line Extraction of Fossil Oyster Shells

NASA Astrophysics Data System (ADS)

Djuricic, A.; Puttonen, E.; Harzhauser, M.; Mandic, O.; Székely, B.; Pfeifer, N.

2016-06-01

Photogrammetry provides a powerful tool to digitally document protected, inaccessible, and rare fossils. This saves manpower in relation to current documentation practice and makes the fragile specimens more available for paleontological analysis and public education. In this study, high resolution orthophoto (0.5 mm) and digital surface models (1 mm) are used to define fossil boundaries that are then used as an input to automatically extract fossil length information via central lines. In general, central lines are widely used in geosciences as they ease observation, monitoring and evaluation of object dimensions. Here, the 3D central lines are used in a novel paleontological context to study fossilized oyster shells with photogrammetric and LiDAR-obtained 3D point cloud data. 3D central lines of 1121 Crassostrea gryphoides oysters of various shapes and sizes were computed in the study. Central line calculation included: i) Delaunay triangulation between the fossil shell boundary points and formation of the Voronoi diagram; ii) extraction of Voronoi vertices and construction of a connected graph tree from them; iii) reduction of the graph to the longest possible central line via Dijkstra's algorithm; iv) extension of longest central line to the shell boundary and smoothing by an adjustment of cubic spline curve; and v) integration of the central line into the corresponding 3D point cloud. The resulting longest path estimate for the 3D central line is a size parameter that can be applied in oyster shell age determination both in paleontological and biological applications. Our investigation evaluates ability and performance of the central line method to measure shell sizes accurately by comparing automatically extracted central lines with manually collected reference data used in paleontological analysis. Our results show that the automatically obtained central line length overestimated the manually collected reference by 1.5% in the test set, which is deemed sufficient for the selected paleontological application, namely shell age determination.

Critical Role for Very-Long Chain Sphingolipids in Invariant Natural Killer T Cell Development and Homeostasis.

PubMed

Saroha, Ashish; Pewzner-Jung, Yael; Ferreira, Natalia S; Sharma, Piyush; Jouan, Youenn; Kelly, Samuel L; Feldmesser, Ester; Merrill, Alfred H; Trottein, François; Paget, Christophe; Lang, Karl S; Futerman, Anthony H

2017-01-01

The role of sphingolipids (SLs) in the immune system has come under increasing scrutiny recently due to the emerging contributions that these important membrane components play in regulating a variety of immunological processes. The acyl chain length of SLs appears particularly critical in determining SL function. Here, we show a role for very-long acyl chain SLs (VLC-SLs) in invariant natural killer T ( i NKT) cell maturation in the thymus and homeostasis in the liver. Ceramide synthase 2-null mice, which lack VLC-SLs, were susceptible to a hepatotropic strain of lymphocytic choriomeningitis virus, which is due to a reduction in the number of i NKT cells. Bone marrow chimera experiments indicated that hematopoietic-derived VLC-SLs are essential for maturation of i NKT cells in the thymus, whereas parenchymal-derived VLC-SLs are crucial for i NKT cell survival and maintenance in the liver. Our findings suggest a critical role for VLC-SL in i NKT cell physiology.

Quantifying prosthetic gait deviation using simple outcome measures

PubMed Central

Kark, Lauren; Odell, Ross; McIntosh, Andrew S; Simmons, Anne

2016-01-01

AIM: To develop a subset of simple outcome measures to quantify prosthetic gait deviation without needing three-dimensional gait analysis (3DGA). METHODS: Eight unilateral, transfemoral amputees and 12 unilateral, transtibial amputees were recruited. Twenty-eight able-bodied controls were recruited. All participants underwent 3DGA, the timed-up-and-go test and the six-minute walk test (6MWT). The lower-limb amputees also completed the Prosthesis Evaluation Questionnaire. Results from 3DGA were summarised using the gait deviation index (GDI), which was subsequently regressed, using stepwise regression, against the other measures. RESULTS: Step-length (SL), self-selected walking speed (SSWS) and the distance walked during the 6MWT (6MWD) were significantly correlated with GDI. The 6MWD was the strongest, single predictor of the GDI, followed by SL and SSWS. The predictive ability of the regression equations were improved following inclusion of self-report data related to mobility and prosthetic utility. CONCLUSION: This study offers a practicable alternative to quantifying kinematic deviation without the need to conduct complete 3DGA. PMID:27335814

Midwavelength interband cascade infrared photodetectors with superlattice absorbers and gain

NASA Astrophysics Data System (ADS)

Lei, Lin; Li, Lu; Lotfi, Hossein; Ye, Hao; Yang, Rui Q.; Mishima, Tetsuya D.; Santos, Michael B.; Johnson, Matthew B.

2018-01-01

We report on a comparison study of the electrical and optical properties of a set of device structures with different numbers of cascade stages, type-II superlattice (T2SL) absorber thickness, and doping variations, as well as a noncurrent-matched interband cascade infrared photodetectors (ICIP) structure with equal absorbers. Multistage ICIPs were demonstrated to be capable of operating at high temperatures at zero-bias with superior carrier transport over comparable conventional one-stage detectors. Based on the temperature dependence and bias sensitivity of their responsivities with various absorber thicknesses, the diffusion length is estimated to be between 0.6 and 1.0 μm for T2SL materials at high temperatures (>250 K). A comparison of responsivities between current matched ICIPs with varied absorber thicknesses and noncurrent-matched ICIPs with equal absorbers shows that the current-matching among cascade stages is necessary to maximize responsivity. Additionally, electrical gain exceeding unity is demonstrated in these detectors in the reverse-illumination configuration.

Fluidized bed calciner apparatus

DOEpatents

Owen, Thomas J.; Klem, Jr., Michael J.; Cash, Robert J.

1988-01-01

An apparatus for remotely calcining a slurry or solution feed stream of toxic or hazardous material, such as ammonium diurante slurry or uranyl nitrate solution, is disclosed. The calcining apparatus includes a vertical substantially cylindrical inner shell disposed in a vertical substantially cylindrical outer shell, in which inner shell is disposed a fluidized bed comprising the feed stream material to be calcined and spherical beads to aid in heat transfer. Extending through the outer and inner shells is a feed nozzle for delivering feed material or a cleaning chemical to the beads. Disposed in and extending across the lower portion of the inner shell and upstream of the fluidized bed is a support member for supporting the fluidized bed, the support member having uniform slots for directing uniform gas flow to the fluidized bed from a fluidizing gas orifice disposed upstream of the support member. Disposed in the lower portion of the inner shell are a plurality of internal electric resistance heaters for heating the fluidized bed. Disposed circumferentially about the outside length of the inner shell are a plurality of external heaters for heating the inner shell thereby heating the fluidized bed. Further, connected to the internal and external heaters is a means for maintaining the fluidized bed temperature to within plus or minus approximately 25.degree. C. of a predetermined bed temperature. Disposed about the external heaters is the outer shell for providing radiative heat reflection back to the inner shell.

Measurement of minority carrier diffusion lengths in GaAs nanowires by a nanoprobe technique

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

Darbandi, A.; Watkins, S. P., E-mail: simonw@sfu.ca

Minority carrier diffusion lengths in both p-type and n-type GaAs nanowires were studied using electron beam induced current by means of a nanoprobe technique without lithographic processing. The diffusion lengths were determined for Au/GaAs rectifying junctions as well as axial p-n junctions. By incorporating a thin lattice-matched InGaP passivating shell, a 2-fold enhancement in the minority carrier diffusion lengths and one order of magnitude reduction in the surface recombination velocity were achieved.

Predicted arterial oxygenation at commercial aircraft cabin altitudes.

PubMed

Muhm, J Michael

2004-10-01

The degree of hypoxia manifested by airline passengers during flight is not well characterized. Statistical models to predict age-specific levels of Pao2 manifest at altitudes between sea level and 8000 ft (Pao2alt) are described. The relationship between age and Pao2 at sea level (Pao2sl) and the relationship between Pao2alt, and Pao2sl, Pco2 at sea level (Pco2sl), and pulmonary health status were investigated using linear regression techniques to analyze previously published data. In persons with normal pulmonary health, the relationship between Pao2sl (mmHg) and age (yr) was Pao2sl = 105.9 - 0.44 * age (R2 = 0.582, MSE = 25.314); Pco2sl (38.1 +/- 2.8 mmHg) was not related to age over the range 18-75 yr. In persons with chronic obstructive lung disease (COPD), neither Pao2sl (78.2 +/- 11.3 mmHg) nor Pco2sl (40.5 +/- 5.7 mmHg) were related to age (77.0 +/- 9.0 yrs).The relationship between PaO2alt and Pao2sl, Pco2sl and altitude (ft) was: Pao2alt = 1.59 + 0.98 * Pao2sl + 0.0031 * Alt - 0.000061 * Pao2sl * Alt - 0.000065 * PCO(2)sl [corrected] * Alt + 0.000000092 * Alt2 (R2 = 0.932, MSE = 22.774). Pao2sl declines with age in persons with normal pulmonary health; Pco2sl remains constant. Neither vary with age in persons with COPD. Pao2alt can be estimated with acceptable precision from knowledge of Pao2sl, Pco2sl, and altitude. These models predict a substantial proportion of older passengers will manifest a Pao2alt at 8000 ft below the threshold at which supplemental oxygen is recommended.

Variation in Orthologous Shell-Forming Proteins Contribute to Molluscan Shell Diversity

PubMed Central

Jackson, Daniel J.; Reim, Laurin; Randow, Clemens; Cerveau, Nicolas; Degnan, Bernard M.; Fleck, Claudia

2017-01-01

Abstract Despite the evolutionary success and ancient heritage of the molluscan shell, little is known about the molecular details of its formation, evolutionary origins, or the interactions between the material properties of the shell and its organic constituents. In contrast to this dearth of information, a growing collection of molluscan shell-forming proteomes and transcriptomes suggest they are comprised of both deeply conserved, and lineage specific elements. Analyses of these sequence data sets have suggested that mechanisms such as exon shuffling, gene co-option, and gene family expansion facilitated the rapid evolution of shell-forming proteomes and supported the diversification of this phylum specific structure. In order to further investigate and test these ideas we have examined the molecular features and spatial expression patterns of two shell-forming genes (Lustrin and ML1A2) and coupled these observations with materials properties measurements of shells from a group of closely related gastropods (abalone). We find that the prominent “GS” domain of Lustrin, a domain believed to confer elastomeric properties to the shell, varies significantly in length between the species we investigated. Furthermore, the spatial expression patterns of Lustrin and ML1A2 also vary significantly between species, suggesting that both protein architecture, and the regulation of spatial gene expression patterns, are important drivers of molluscan shell evolution. Variation in these molecular features might relate to certain materials properties of the shells of these species. These insights reveal an important and underappreciated source of variation within shell-forming proteomes that must contribute to the diversity of molluscan shell phenotypes. PMID:28961798

Towards a theory of individual differences in statistical learning

PubMed Central

Bogaerts, Louisa; Christiansen, Morten H.; Frost, Ram

2017-01-01

In recent years, statistical learning (SL) research has seen a growing interest in tracking individual performance in SL tasks, mainly as a predictor of linguistic abilities. We review studies from this line of research and outline three presuppositions underlying the experimental approach they employ: (i) that SL is a unified theoretical construct; (ii) that current SL tasks are interchangeable, and equally valid for assessing SL ability; and (iii) that performance in the standard forced-choice test in the task is a good proxy of SL ability. We argue that these three critical presuppositions are subject to a number of theoretical and empirical issues. First, SL shows patterns of modality- and informational-specificity, suggesting that SL cannot be treated as a unified construct. Second, different SL tasks may tap into separate sub-components of SL that are not necessarily interchangeable. Third, the commonly used forced-choice tests in most SL tasks are subject to inherent limitations and confounds. As a first step, we offer a methodological approach that explicitly spells out a potential set of different SL dimensions, allowing for better transparency in choosing a specific SL task as a predictor of a given linguistic outcome. We then offer possible methodological solutions for better tracking and measuring SL ability. Taken together, these discussions provide a novel theoretical and methodological approach for assessing individual differences in SL, with clear testable predictions. This article is part of the themed issue ‘New frontiers for statistical learning in the cognitive sciences’. PMID:27872377

Pseudotrichonotus belos new species, first record of the fish family Pseudotrichonotidae from Australia (Teleostei: Aulopiformes).

PubMed

Gill, Anthony C; Pogonoski, John J

2016-12-05

Pseudotrichonotus belos new species, described from three specimens trawled in 100-120 m offshore between Exmouth Gulf and Shark Bay, Western Australia, represents the first record of the sand-diving fish family Pseudotrichonotidae from Australian waters. It differs from its two congeners in having a more posteriorly positioned dorsal fin (predorsal length 39.6-41.2 % SL) and fewer dorsal- and anal-fin rays (31-33 and 12, respectively).

SlMAPK3 enhances tolerance to tomato yellow leaf curl virus (TYLCV) by regulating salicylic acid and jasmonic acid signaling in tomato (Solanum lycopersicum)

PubMed Central

Li, Yunzhou; Qin, Lei; Zhao, Jingjing; Muhammad, Tayeb; Cao, Hehe; Li, Hailiang; Zhang, Yan; Liang, Yan

2017-01-01

Several recent studies have reported on the role of mitogen-activated protein kinase (MAPK3) in plant immune responses. However, little is known about how MAPK3 functions in tomato (Solanum lycopersicum L.) infected with tomato yellow leaf curl virus (TYLCV). There is also uncertainty about the connection between plant MAPK3 and the salicylic acid (SA) and jasmonic acid (JA) defense-signaling pathways. The results of this study indicated that SlMAPK3 participates in the antiviral response against TYLCV. Tomato seedlings were inoculated with TYLCV to investigate the possible roles of SlMAPK1, SlMAPK2, and SlMAPK3 against this virus. Inoculation with TYLCV strongly induced the expression and the activity of all three genes. Silencing of SlMAPK1, SlMAPK2, and SlMAPK3 reduced tolerance to TYLCV, increased leaf H2O2 concentrations, and attenuated expression of defense-related genes after TYLCV infection, especially in SlMAPK3-silenced plants. Exogenous SA and methyl jasmonic acid (MeJA) both significantly induced SlMAPK3 expression in tomato leaves. Over-expression of SlMAPK3 increased the transcript levels of SA/JA-mediated defense-related genes (PR1, PR1b/SlLapA, SlPI-I, and SlPI-II) and enhanced tolerance to TYLCV. After TYLCV inoculation, the leaves of SlMAPK3 over-expressed plants compared with wild type plants showed less H2O2 accumulation and greater superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activity. Overall, the results suggested that SlMAPK3 participates in the antiviral response of tomato to TYLCV, and that this process may be through either the SA or JA defense-signaling pathways. PMID:28222174

SlMAPK3 enhances tolerance to tomato yellow leaf curl virus (TYLCV) by regulating salicylic acid and jasmonic acid signaling in tomato (Solanum lycopersicum).

PubMed

Li, Yunzhou; Qin, Lei; Zhao, Jingjing; Muhammad, Tayeb; Cao, Hehe; Li, Hailiang; Zhang, Yan; Liang, Yan

2017-01-01

Several recent studies have reported on the role of mitogen-activated protein kinase (MAPK3) in plant immune responses. However, little is known about how MAPK3 functions in tomato (Solanum lycopersicum L.) infected with tomato yellow leaf curl virus (TYLCV). There is also uncertainty about the connection between plant MAPK3 and the salicylic acid (SA) and jasmonic acid (JA) defense-signaling pathways. The results of this study indicated that SlMAPK3 participates in the antiviral response against TYLCV. Tomato seedlings were inoculated with TYLCV to investigate the possible roles of SlMAPK1, SlMAPK2, and SlMAPK3 against this virus. Inoculation with TYLCV strongly induced the expression and the activity of all three genes. Silencing of SlMAPK1, SlMAPK2, and SlMAPK3 reduced tolerance to TYLCV, increased leaf H2O2 concentrations, and attenuated expression of defense-related genes after TYLCV infection, especially in SlMAPK3-silenced plants. Exogenous SA and methyl jasmonic acid (MeJA) both significantly induced SlMAPK3 expression in tomato leaves. Over-expression of SlMAPK3 increased the transcript levels of SA/JA-mediated defense-related genes (PR1, PR1b/SlLapA, SlPI-I, and SlPI-II) and enhanced tolerance to TYLCV. After TYLCV inoculation, the leaves of SlMAPK3 over-expressed plants compared with wild type plants showed less H2O2 accumulation and greater superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activity. Overall, the results suggested that SlMAPK3 participates in the antiviral response of tomato to TYLCV, and that this process may be through either the SA or JA defense-signaling pathways.

Folding of non-Euclidean curved shells

NASA Astrophysics Data System (ADS)

Bende, Nakul; Evans, Arthur; Innes-Gold, Sarah; Marin, Luis; Cohen, Itai; Santangelo, Christian; Hayward, Ryan

2015-03-01

Origami-based folding of 2D sheets has been of recent interest for a variety of applications ranging from deployable structures to self-folding robots. Though folding of planar sheets follows well-established principles, folding of curved shells involves an added level of complexity due to the inherent influence of curvature on mechanics. In this study, we use principles from differential geometry and thin shell mechanics to establish fundamental rules that govern folding of prototypical creased shells. In particular, we show how the normal curvature of a crease line controls whether the deformation is smooth or discontinuous, and investigate the influence of shell thickness and boundary conditions. We show that snap-folding of shells provides a route to rapid actuation on time-scales dictated by the speed of sound. The simple geometric design principles developed can be applied at any length-scale, offering potential for bio-inspired soft actuators for tunable optics, microfluidics, and robotics. This work was funded by the National Science Foundation through EFRI ODISSEI-1240441 with additional support to S.I.-G. through the UMass MRSEC DMR-0820506 REU program.

Cephalopod embryonic shells as a tool to reconstruct reproductive strategies in extinct taxa.

PubMed

Laptikhovsky, Vladimir; Nikolaeva, Svetlana; Rogov, Mikhail

2018-02-01

An exhaustive study of existing data on the relationship between egg size and maximum size of embryonic shells in 42 species of extant cephalopods demonstrated that these values are approximately equal regardless of taxonomy and shell morphology. Egg size is also approximately equal to mantle length of hatchlings in 45 cephalopod species with rudimentary shells. Paired data on the size of the initial chamber versus embryonic shell in 235 species of Ammonoidea, 46 Bactritida, 13 Nautilida, 22 Orthocerida, 8 Tarphycerida, 4 Oncocerida, 1 Belemnoidea, 4 Sepiida and 1 Spirulida demonstrated that, although there is a positive relationship between these parameters in some taxa, initial chamber size cannot be used to predict egg size in extinct cephalopods; the size of the embryonic shell may be more appropriate for this task. The evolution of reproductive strategies in cephalopods in the geological past was marked by an increasing significance of small-egged taxa, as is also seen in simultaneously evolving fish taxa. © 2017 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.

Core-shell structure of Miglyol/poly(D,L-lactide)/Poloxamer nanocapsules studied by small-angle neutron scattering.

PubMed

Rübe, Andrea; Hause, Gerd; Mäder, Karsten; Kohlbrecher, Joachim

2005-10-03

The contrast variation technique in small angle neutron scattering (SANS) was used to investigate the inner structure of nanocapsules on the example of poly(D,L-lactide) (PLA) nanocapsules. The determination of the PLA and Poloxamer shell thickness was the focus of this study. Highest sensitivity on the inner structure of the nanocapsules was obtained when the scattering length density of the solvent was varied between the one of the Miglyol core and the PLA shell. According to the fit data the PLA shell thickness was 9.8 nm. The z-averaged radius determined by SANS experiments correlated well with dynamic light scattering (DLS) results, although DLS values were systematically slightly higher than the ones measured by SANS. This could be explained by taking into account the influence of Poloxamer attached to the nanocapsules surface. For a refined fit model with a second shell consisting of Poloxamer, SANS values and DLS values fitted well with each other. The characterization method presented here is significant because detailed insights into the nanocapsule and the Poloxamer shell were gained for the first time. This method could be used to develop strategies for the optimization of the shell properties concerning controlled release and to study changes in the shell structure during degradation processes.

Suppression of 9-cis-epoxycarotenoid dioxygenase, which encodes a key enzyme in abscisic acid biosynthesis, alters fruit texture in transgenic tomato.

PubMed

Sun, Liang; Sun, Yufei; Zhang, Mei; Wang, Ling; Ren, Jie; Cui, Mengmeng; Wang, Yanping; Ji, Kai; Li, Ping; Li, Qian; Chen, Pei; Dai, Shengjie; Duan, Chaorui; Wu, Yan; Leng, Ping

2012-01-01

Cell wall catabolism during fruit ripening is under complex control and is key for fruit quality and shelf life. To examine the role of abscisic acid (ABA) in tomato (Solanum lycopersicum) fruit ripening, we suppressed SlNCED1, which encodes 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in the biosynthesis of ABA. To suppress SlNCED1 specifically in tomato fruits, and thus avoid the pleiotropic phenotypes associated with ABA deficiency, we used an RNA interference construct driven by the fruit-specific E8 promoter. ABA accumulation and SlNCED1 transcript levels in the transgenic fruit were down-regulated to between 20% and 50% of the levels measured in the control fruit. This significant reduction in NCED activity led to a down-regulation in the transcription of genes encoding major cell wall catabolic enzymes, specifically polygalacturonase (SlPG), pectin methyl esterase (SlPME), β-galactosidase precursor mRNA (SlTBG), xyloglucan endotransglycosylase (SlXET), endo-1,4-β-cellulose (SlCels), and expansin (SlExp). This resulted in an increased accumulation of pectin during ripening. In turn, this led to a significant extension of the shelf life to 15 to 29 d compared with a shelf life of only 7 d for the control fruit and an enhancement of fruit firmness at the mature stage by 30% to 45%. In conclusion, ABA affects cell wall catabolism during tomato fruit ripening via down-regulation of the expression of major catabolic genes (SlPG, SlPME, SlTBG, SlXET, SlCels, and SlExp).

Using morphometrics to identify glochidia from a diverse freshwater mussel community

Treesearch

Thomas B. Kennedy; Wendell R. Haag

2005-01-01

We measured shell length, hinge length, and height of glochidia from 21 freshwater mussel species occurring in the Sipsey River, Alabama, to test our ability to identify species based on these glochidial morphometrics. Glochidial size and shape differed widely among species; for all 3 dimensions, mean values for the largest species were 5 to 73 greater than for the...

Enhanced cardioprotection against ischemia-reperfusion injury with combining sildenafil with low-dose atorvastatin.

PubMed

Rosanio, Salvatore; Ye, Yumei; Atar, Shaul; Rahman, Atiar M; Freeberg, Sheldon Y; Huang, Ming-He; Uretsky, Barry F; Birnbaum, Yochai

2006-02-01

Both ATV and SL reduce myocardial infarct size (IS) by enhancing expression and activity of NOS isoforms. We investigated whether atorvastatin (ATV) and sildenafil (SL) have synergistic effects on myocardial infarct size (IS) reduction and enhancing nitric oxide synthase (NOS) expression. Rats were randomized to nine groups: ATV-1 (1 mg/kg/d); ATV-10 (10 mg/kg/d); SL-0.7 (0.7 mg/kg); SL-1 (1 mg/kg); ATV-1 + SL-0.7; water alone (controls); 1400W (iNOS inhibitor; 1 mg/kg); ATV-10 + 1400W; and ATV-1 + SL-0.7 + 1400W. ATV was administered orally for 3 days. SL was administered intraperitoneally 18 h before surgery and 1400W intravenously 15 min before surgery. Rats either underwent 30 min ischemia-4 h reperfusion or the hearts were explanted for immunoblotting and enzyme activity tests without being exposed to ischemia. IS (% risk area, mean +/- SEM) was smaller in the ATV-10 (13 +/- 1%), SL-1 (11 +/- 2%), SL-0.7 (18 +/- 2%) and ATV-1 + SL-0.7 (9 +/- 1%) groups as compared with controls (34 +/- 3%; P < 0.001), whereas ATV-1 had no effect (29 +/- 2%). ATV-1 + SL-0.7 (9 +/- 1%) reduced IS more than SL-0.7 alone (p = 0.012). 1400W abrogated the protective effect of ATV-10 (35 +/- 3%) and ATV-1 + SL-0.7 (34 +/- 1%). SL-0.7 and ATV-10 increased phosphorylated endothelial (P-eNOS; 210 +/- 2.5% and 220 +/- 8%) and inducible (iNOS; 151 +/- 1% and 154 +/- 1%) NOS expression, whereas ATV-1 did not. These changes were significantly enhanced by ATV-1 + SL-0.7 (P-eNOS, 256 +/- 2%, iNOS 195 +/- 1%). SL-1 increased P-eNOS (311 +/- 22%) and iNOS (185 +/- 1%) concentrations. Combining low-dose ATV with SL augments the IS limiting effects through enhanced P-eNOS and iNOS expression.

Does seawater acidification affect survival, growth and shell integrity in bivalve juveniles?

PubMed

Bressan, M; Chinellato, A; Munari, M; Matozzo, V; Manci, A; Marčeta, T; Finos, L; Moro, I; Pastore, P; Badocco, D; Marin, M G

2014-08-01

Anthropogenic emissions of carbon dioxide are leading to decreases in pH and changes in the carbonate chemistry of seawater. Ocean acidification may negatively affect the ability of marine organisms to produce calcareous structures while also influencing their physiological responses and growth. The aim of this study was to evaluate the effects of reduced pH on the survival, growth and shell integrity of juveniles of two marine bivalves from the Northern Adriatic sea: the Mediterranean mussel Mytilus galloprovincialis and the striped venus clam Chamelea gallina. An outdoor flow-through plant was set up and two pH levels (natural seawater pH as a control, pH 7.4 as the treatment) were tested in long-term experiments. Mortality was low throughout the first experiment for both mussels and clams, but a significant increase, which was sensibly higher in clams, was observed at the end of the experiment (6 months). Significant decreases in the live weight (-26%) and, surprisingly, in the shell length (-5%) were observed in treated clams, but not in mussels. In the controls of both species, no shell damage was ever recorded; in the treated mussels and clams, damage proceeded via different modes and to different extents. The severity of shell injuries was maximal in the mussels after just 3 months of exposure to a reduced pH, whereas it progressively increased in clams until the end of the experiment. In shells of both species, the damaged area increased throughout the experiment, peaking at 35% in mussels and 11% in clams. The shell thickness of the treated and control animals significantly decreased after 3 months in clams and after 6 months in mussels. In the second experiment (3 months), only juvenile mussels were exposed to a reduced pH. After 3 months, the mussels at a natural pH level or pH 7.4 did not differ in their survival, shell length or live weight. Conversely, shell damage was clearly visible in the treated mussels from the 1st month onward. Monitoring the chemistry of seawater carbonates always showed aragonite undersaturation at 7.4 pH, whereas calcite undersaturation occurred in only 37% of the measurements. The present study highlighted the contrasting effects of acidification in two bivalve species living in the same region, although not exactly in the same habitat. Copyright © 2014 Elsevier Ltd. All rights reserved.

The tomato plastidic fructokinase SlFRK3 plays a role in xylem development.

PubMed

Stein, Ofer; Damari-Weissler, Hila; Secchi, Francesca; Rachmilevitch, Shimon; German, Marcelo A; Yeselson, Yelena; Amir, Rachel; Schaffer, Arthur; Holbrook, N Michele; Aloni, Roni; Zwieniecki, Maciej A; Granot, David

2016-03-01

Plants have two kinds of fructokinases (FRKs) that catalyze the key step of fructose phosphorylation, cytosolic and plastidic. The major cytosolic tomato FRK, SlFRK2, is essential for the development of xylem vessels. In order to study the role of SlFRK3, which encodes the only plastidic FRK, we generated transgenic tomato (Solanum lycopersicon) plants with RNAi suppression of SlFRK3 as well as plants expressing beta-glucoronidase (GUS) under the SlFRK3 promoter. GUS staining indicated SlFRK3 expression in vascular tissues of the leaves and stems, including cambium, differentiating xylem, young xylem fibers and phloem companion cells. Suppression of SlFRK3 reduced the stem xylem area, stem and root water conductance, and whole-plant transpiration, with minor effects on plant development. However, suppression of SlFRK3 accompanied by partial suppression of SlFRK2 induced significant growth-inhibition effects, including the wilting of mature leaves. Grafting experiments revealed that these growth effects are imposed primarily by the leaves, whose petioles had unlignified, thin-walled xylem fibers with collapsed parenchyma cells around the vessels. A cross between the SlFRK2-antisense and SlFRK3-RNAi lines exhibited similar wilting and anatomical effects, confirming that these effects are the result of the combined suppression of SlFRK3 and SlFRK2. These results demonstrate a role of the plastidic SlFRK3 in xylem development and hydraulic conductance. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest). Pile Perch, Striped Seaperch, and Rubberlip Seaperch

DTIC Science & Technology

1989-07-01

The largest of the teeth on vomer or palatines . surfperches, reaching a maximum length Branchiostegals 5-6; gill membranes of 47 cm TL (Eschmeyer et...Fritzsche 1982). dorsal surface. Fins dusky (Tarp 1952). Maximum length 44 cm total length (TL) (Eschmeyer et al. 1983). LIFE HISTORY Embiotoca lateralis...developed, shore. From 1958 to 1961, sport fused pharyngeal tooth plates that fishermen caught an estimated 5,000 enable the fish to crush hard-shelled

Experimental Investigations, Modeling, and Analyses of High-Temperature Devices for Space Applications. Part 1

DTIC Science & Technology

1999-01-01

Cylinder and Another Interior Shell of Different Length (Reid and Tennant 1973) 429 C. 1.19. View Factors between Two Infinitely-Long Parallel and Opposed...by Another Parallel Cylinder of Different Radius 433 X C. 1.21. View Factor between Two Parallel and Opposed Cylinders of Unequal Radii and Equal...Length (Juul 1982) 435 C. 1.22. View Factor between Two Parallel Cylindrical Sections at Different Levels and of Different Length 439 C.2 CALCULATION OF

Tomato SlAN11 regulates flavonoid biosynthesis and seed dormancy by interaction with bHLH proteins but not with MYB proteins.

PubMed

Gao, Yongfeng; Liu, Jikai; Chen, Yongfu; Tang, Hai; Wang, Yang; He, Yongmei; Ou, Yongbin; Sun, Xiaochun; Wang, Songhu; Yao, Yinan

2018-01-01

The flavonoid compounds are important secondary metabolites with versatile human nutritive benefits and fulfill a multitude of functions during plant growth and development. The abundance of different flavonoid compounds are finely tuned with species-specific pattern by a ternary MBW complex, which consists of a MYB, a bHLH, and a WD40 protein, but the essential role of SlAN11, which is a WD40 protein, is not fully understood in tomato until now. In this study, a tomato WD40 protein named as SlAN11 was characterized as an effective transcription regulator to promote plant anthocyanin and seed proanthocyanidin (PA) contents, with late flavonoid biosynthetic genes activated in 35S::SlAN11 transgenic lines, while the dihydroflavonol flow to the accumulation of flavonols or their glycosylated derivatives was reduced by repressing the expression of SlFLS in this SlAN11 -overexpressed lines. The above changes were reversed in 35S::SlAN11-RNAi transgenic lines except remained levels of flavonol compounds and SlFLS expression. Interestingly, our data revealed that SlAN11 gene could affect seed dormancy by regulating the expressions of abscisic acid (ABA) signaling-related genes SlABI3 and SlABI5 , and the sensitivity to ABA treatment in seed germination is conversely changed by SlAN11 -overexpressed or -downregulated lines. Yeast two-hybrid assays demonstrated that SlAN11 interacted with bHLH but not with MYB proteins in the ternary MBW complex, whereas bHLH interacted with MYB in tomato. Our results indicated that low level of anthocyanins in tomato fruits, with low expression of bHLH ( SlTT8 ) and MYB ( SlANT1 and SlAN2 ) genes, remain unchanged upon modification of SlAN11 gene alone in the transgenic lines. These results suggest that the tomato WD40 protein SlAN11, coordinating with bHLH and MYB proteins, plays a crucial role in the fine adjustment of the flavonoid biosynthesis and seed dormancy in tomato.

SL2-like spliced leader RNAs in the basal nematode Prionchulus punctatus: New insight into the evolution of nematode SL2 RNAs.

PubMed

Harrison, Neale; Kalbfleisch, Andreas; Connolly, Bernadette; Pettitt, Jonathan; Müller, Berndt

2010-08-01

Spliced-leader (SL) trans-splicing has been found in all molecularly characterized nematode species to date, and it is likely to be a nematode synapomorphy. Most information regarding SL trans-splicing has come from the study of nematodes from a single monophyletic group, the Rhabditida, all of which employ SL RNAs that are identical to, or variants of, the SL1 RNA first characterized in Caenorhabditis elegans. In contrast, the more distantly related Trichinella spiralis, belonging to the subclass Dorylaimia, utilizes a distinct set of SL RNAs that display considerable sequence diversity. To investigate whether this is true of other members of the Dorylaimia, we have characterized SL RNAs from Prionchulus punctatus. Surprisingly, this revealed the presence of a set of SLs that show clear sequence similarity to the SL2 family of spliced leaders, which have previously only been found within the rhabditine group (which includes C. elegans). Expression of one of the P. punctatus SL RNAs in C. elegans reveals that it can compete specifically with the endogenous C. elegans SL2 spliced leaders, being spliced to the pre-mRNAs derived from downstream genes in operons, but does not compete with the SL1 spliced leaders. This discovery raises the possibility that SL2-like spliced leaders were present in the last common ancestor of the nematode phylum.

Bioaccumulation of metals in the soft tissue of Patella aspera: Application of metal/shell weight indices

NASA Astrophysics Data System (ADS)

Cravo, A.; Bebianno, M. J.

2005-11-01

Patella aspera limpets were taken from a marine clean site (MCS) and an estuarine contaminated site (ECS). The concentrations of Fe, Mn, Zn, Cu, Cd, Ni and Co were determined individually over the available size range. Since there were significant differences in the soft tissue weight between populations, but shell characteristics were similar (length and weight), metal/shell weight indices (MSI) were calculated in order to compare populations. For both populations iron, zinc and manganese/shell weight indices were consistently higher, in the order Fe ≫ Zn ≫ Mn than those of Cu, Ni, Co and Cd. The results exhibited a marked intra- and inter-population variability. The highest intra-variability was observed at ECS, particularly where a strong effect of shell weight upon the metal accumulation in the soft tissue was evident. Due to this effect, the comparison of populations was carried out between three selected shell weight ranges representative of light shells (0.45-1.95 g), intermediate shells (2.95-4.45 g) and heavy shells (5.45-7.33 g). The results indicate that, in general, MSI at ECS (a sewage contaminated site), except for Cd, was higher than at MCS possibly reflecting a higher environmental bioavailability of these metals. The resolution between populations was higher when the smallest range of limpets was considered and it decreased with the increase of shell weight. The highest discrimination amongst populations was found for zinc/shell weight index that showed much higher values than those of Mn, Cu, Cd, Ni and Co/shell weight indices, and spatial differentiation between populations persisted amongst the selected shell weight ranges.

Variation in Orthologous Shell-Forming Proteins Contribute to Molluscan Shell Diversity.

PubMed

Jackson, Daniel J; Reim, Laurin; Randow, Clemens; Cerveau, Nicolas; Degnan, Bernard M; Fleck, Claudia

2017-11-01

Despite the evolutionary success and ancient heritage of the molluscan shell, little is known about the molecular details of its formation, evolutionary origins, or the interactions between the material properties of the shell and its organic constituents. In contrast to this dearth of information, a growing collection of molluscan shell-forming proteomes and transcriptomes suggest they are comprised of both deeply conserved, and lineage specific elements. Analyses of these sequence data sets have suggested that mechanisms such as exon shuffling, gene co-option, and gene family expansion facilitated the rapid evolution of shell-forming proteomes and supported the diversification of this phylum specific structure. In order to further investigate and test these ideas we have examined the molecular features and spatial expression patterns of two shell-forming genes (Lustrin and ML1A2) and coupled these observations with materials properties measurements of shells from a group of closely related gastropods (abalone). We find that the prominent "GS" domain of Lustrin, a domain believed to confer elastomeric properties to the shell, varies significantly in length between the species we investigated. Furthermore, the spatial expression patterns of Lustrin and ML1A2 also vary significantly between species, suggesting that both protein architecture, and the regulation of spatial gene expression patterns, are important drivers of molluscan shell evolution. Variation in these molecular features might relate to certain materials properties of the shells of these species. These insights reveal an important and underappreciated source of variation within shell-forming proteomes that must contribute to the diversity of molluscan shell phenotypes. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Supplementation of soybean lecithin-based semen extender by antioxidants: complementary flowcytometric study on post-thawed ram spermatozoa.

PubMed

Sharafi, Mohsen; Zhandi, Mahdi; Akbari Sharif, Abbas

2015-06-01

The purpose of the current study was to evaluate the effects of cysteine (C) and glutathione (G) on the post-thawed ram sperm quality. Collected semen samples from four mature rams were diluted with five soybean lecithin (SL)-based extenders containing: no antioxidant (SL-0), 5 mM cysteine (SL-C5), 10 mM cysteine (SL-C10), 5 mM glutathione (SL-G5) and 10 mM glutathione (SL-G10). After freeze-thawing process, motion and velocity parameters, plasma membrane integrity and functionality, morphological abnormality, lipid peroxidation, acrosomal status, mitochondria activity, and apoptosis status of post-thawed ram spermatozoa were assessed. The results showed that SL-C10 increased the total motility and plasma membrane integrity (p < 0.05) of post-thawed ram spermatozoa (55.86 ± 1.37 and 60.57 ± 1.34 %) compared to other extenders. Progressive motility was significantly higher in SL-C10 (24.71 ± 1.13 %) compared to SL-0 (20 ± 1.13 %) and SL-G10 (15 ± 1.13 %). Mitochondrial activity was significantly higher in SL-C10 (56.83 ± 2.29 %) compared to SL-G10 (38.75 ± 2.29 %). Capacitation and acrosomal status, lipid peroxidation, and the percentage of dead spermatozoa were not affected by different extenders. The percentage of live spermatozoa was higher in SL-C10 (56.33 ± 1.35 %) compared to other extenders. Also, SL-C10 resulted in a lower percentage of apoptotic spermatozoa (14.17 ± 0.53 %) compared to other extenders. The results of this study showed that supplementation of SL-based ram semen extender with 10 mM cysteine resulted in an improved quality of post-thawed ram spermatozoa.

Suppression of 9-cis-Epoxycarotenoid Dioxygenase, Which Encodes a Key Enzyme in Abscisic Acid Biosynthesis, Alters Fruit Texture in Transgenic Tomato1[W][OA

PubMed Central

Sun, Liang; Sun, Yufei; Zhang, Mei; Wang, Ling; Ren, Jie; Cui, Mengmeng; Wang, Yanping; Ji, Kai; Li, Ping; Li, Qian; Chen, Pei; Dai, Shengjie; Duan, Chaorui; Wu, Yan; Leng, Ping

2012-01-01

Cell wall catabolism during fruit ripening is under complex control and is key for fruit quality and shelf life. To examine the role of abscisic acid (ABA) in tomato (Solanum lycopersicum) fruit ripening, we suppressed SlNCED1, which encodes 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in the biosynthesis of ABA. To suppress SlNCED1 specifically in tomato fruits, and thus avoid the pleiotropic phenotypes associated with ABA deficiency, we used an RNA interference construct driven by the fruit-specific E8 promoter. ABA accumulation and SlNCED1 transcript levels in the transgenic fruit were down-regulated to between 20% and 50% of the levels measured in the control fruit. This significant reduction in NCED activity led to a down-regulation in the transcription of genes encoding major cell wall catabolic enzymes, specifically polygalacturonase (SlPG), pectin methyl esterase (SlPME), β-galactosidase precursor mRNA (SlTBG), xyloglucan endotransglycosylase (SlXET), endo-1,4-β-cellulose (SlCels), and expansin (SlExp). This resulted in an increased accumulation of pectin during ripening. In turn, this led to a significant extension of the shelf life to 15 to 29 d compared with a shelf life of only 7 d for the control fruit and an enhancement of fruit firmness at the mature stage by 30% to 45%. In conclusion, ABA affects cell wall catabolism during tomato fruit ripening via down-regulation of the expression of major catabolic genes (SlPG, SlPME, SlTBG, SlXET, SlCels, and SlExp). PMID:22108525

Responses to two-way selection on growth in mass-spawned F1 progeny of Argopecten irradians concentricus (Say)

NASA Astrophysics Data System (ADS)

Wang, Hui; Liu, Jin; Li, Yanhong; Zhu, Xiaowen; Liu, Zhigang

2014-03-01

In the present study, the effect of one-generation divergent selection on the growth and survival of the bay scallop ( Argopecten irradians concentricus) was examined to evaluate the efficacy of a selection program currently being carried out in Beibu Bay in the South China Sea. A total of 146 adult scallops were randomly selected from the same cultured population of A. i. concentricus, and divided into two groups in shell length (anterior-posterior measurement): large (4.91-6.02 cm, n=74) and small (3.31-4.18 cm, n=72). At the same time, a control group was also randomly sampled (4.21-4.88 cm, n =80). Mass-spawned F 1 progenies from the three size groups were obtained and reared under identical conditions at all growth phases. The effects of two-way (or upward-downward) selection on fertilization rate, hatching rate, survival rate, daily growth in shell length and body weight were assessed in the three size groups. Results show that significant differences ( P<0.01) were found in hatching rate, survival rate and daily growth of F1 progenies, but not in fertilization rate ( P>0.05), among the three groups. The hatching rate, survival rate and daily growth of the progeny of large-sized parents were greater than those of the control group ( P<0.05), which in turn were larger than those of small-sized group ( P<0.05). Responses to selection by shell length and body weight were 0.32 ± 0.04 cm and 2.18 ± 0.05 g, respectively, for the upward selection, and -0.14 ± 0.03 cm and -2.77 ± 0.06 g, respectively, for the downward selection. The realized heritability estimates of shell length and body weight were 0.38 ± 0.06 cm and 0.22 ± 0.07 g for the upward selection, and 0.24 ± 0.06 cm and 0.37 ± 0.09 g for the downward selection, respectively. The change in growth by bidirectional selection suggests that high genetic variation may be present in the cultured bay scallop population in China.

Parametric Studies Of Lightweight Reflectors Supported On Linear Actuator Arrays

NASA Astrophysics Data System (ADS)

Seibert, George E.

1987-10-01

This paper presents the results of numerous design studies carried out at Perkin-Elmer in support of the design of large diameter controllable mirrors for use in laser beam control, surveillance, and astronomy programs. The results include relationships between actuator location and spacing and the associated degree of correctability attainable for a variety of faceplate configurations subjected to typical disturbance environments. Normalizations and design curves obtained from closed-form equations based on thin shallow shell theory and computer based finite-element analyses are presented for use in preliminary design estimates of actuator count, faceplate structural properties, system performance prediction and weight assessments. The results of the analyses were obtained from a very wide range of mirror configurations, including both continuous and segmented mirror geometries. Typically, the designs consisted of a thin facesheet controlled by point force actuators which in turn were mounted on a structurally efficient base panel, or "reaction structure". The faceplate materials considered were fused silica, ULE fused silica, Zerodur, aluminum and beryllium. Thin solid faceplates as well as rib-reinforced cross-sections were treated, with a wide variation in thickness and/or rib patterns. The magnitude and spatial frequency distribution of the residual or uncorrected errors were related to the input error functions for mirrors of many different diameters and focal ratios. The error functions include simple sphere-to-sphere corrections, "parabolization" of spheres, and higher spatial frequency input error maps ranging from 0.5 to 7.5 cycles per diameter. The parameter which dominates all of the results obtained to date, is a structural descriptor of thin shell behavior called the characteristic length. This parameter is a function of the shell's radius of curvature, thickness, and Poisson's ratio of the material used. The value of this constant, in itself, describes the extent to which the deflection under a point force is localized by the shell's curvature. The deflection shape is typically a near-gaussian "bump" with a zero-crossing at a local radius of approximately 3.5 characteristic lengths. The amplitude is a function of the shells elastic modulus, radius, and thickness, and is linearly proportional to the applied force. This basic shell behavior is well-treated in an excellent set of papers by Eric Reissner entitled "Stresses and Small Displacements of Shallow Spherical Shells".1'2 Building on the insight offered by these papers, we developed our design tools around two derived parameters, the ratio of the mirror's diameter to its characteristic length (D/l), and the ratio of the actuator spacing to the characteristic length (b/l). The D/1 ratio determines the "finiteness" of the shell, or its dependence on edge boundary conditions. For D/1 values greater than 10, the influence of edges is almost totally absent on interior behavior. The b/1 ratio, the basis of all our normalizations is the most universal term in the description of correctability or ratio of residual/input errors. The data presented in the paper, shows that the rms residual error divided by the peak amplitude of the input error function is related to the actuator spacing to characteristic length ratio by the following expression RMS Residual Error b 3.5 k (I) (1) Initial Error Ampl. The value of k ranges from approximately 0.001 for low spatial frequency initial errors up to 0.05 for higher error frequencies (e.g. 5 cycles/diameter). The studies also yielded insight to the forces required to produce typical corrections at both the center and edges of the mirror panels. Additionally, the data lends itself to rapid evaluation of the effects of trading faceplate weight for increased actuator count,

Optimization of ram semen cryopreservation using a chemically defined soybean lecithin-based extender.

PubMed

Emamverdi, M; Zhandi, M; Zare Shahneh, A; Sharafi, M; Akbari-Sharif, A

2013-12-01

The purpose of the present study was to investigate the effects of a chemically defined soybean lecithin-based semen extender as a substitute for egg yolk-based extenders in ram semen cryopreservation. In this study, 28 ejaculates were collected from four Zandi rams in the breeding season and then pooled together. The pooled semen was divided into six equal aliquots and diluted with six different extenders: (i) Tris-based extender (TE) containing 0.5% (w/v) soybean lecithin (SL0.5), (ii) TE containing 1% (w/v) soybean lecithin (SL1), (iii) TE containing 1.5% (w/v) soybean lecithin (SL1.5), (iv) TE containing 2% (w/v) soybean lecithin (SL2), (v) TE containing 2.5% (w/v) soybean lecithin (SL2.5) and (vi) TE containing 20% (v/v) egg yolk (EYT). After thawing, sperm motility and motion parameters, plasma membrane and acrosome integrity, apoptosis status and mitochondrial activity were evaluated. The results shown that total and progressive motility (54.43 ± 1.33% and 25.43 ± 0.96%, respectively) were significantly higher in SL1.5 when compared to other semen extenders. Sperm motion parameters (VAP, VSL, VCL, ALH and STR) were significantly higher in SL1.5 compared to other extender, with the exception of SL1 extender. Plasma membrane integrity (48.86 ± 1.38%) was significantly higher in SL1.5 when compared to other semen extenders. Also, percentage of spermatozoa with intact acrosome in SL1.5 (85.35 ± 2.19%) extender was significantly higher than that in SL0.5, SL2.5 and EYT extenders. The results showed that the proportion of live post-thawed sperm was significantly increased in SL1.5 extender compared to SL0.5, SL2 and EYT extenders. In addition, SL1, SL1.5 and SL2.5 extenders resulted in significantly lower percentage of early-apoptotic sperm than that in EYT extender. There were no significant differences in different semen extenders for percentage of post-thawed necrotic and late-apoptotic spermatozoa. Also, the results indicated that there are slight differences for percentage of live spermatozoa with active mitochondria between extenders. In conclusion, SL1.5 extender was better than other extenders in most in vitro evaluated sperm parameters. © 2013 Blackwell Verlag GmbH.

Sharp focusing of laser light by multilayer cylinders with circular cross-section

NASA Astrophysics Data System (ADS)

Kozlova, E. S.

2018-04-01

In this paper, the focusing of laser light at 532 nm by dielectric cylinders with a metal shells is studied by using COMSOL Multiphysics. The analysis of cylinder design which proposed multilayered shell shows that a microcylinder with a gold-silver (or silver-gold) shell can improve the focusing process, especially in the case of TM polarization. The microcylinder with thin internal silver layer of 1 nm and outside gold layer of 9 nm focus TE-polarized light to nanojet with maximal intensity of 5.65 a.u., full width and full length at half maximum of intensity of of 0.39λ and 0.72λ, respectively.

Study of XAFS of some Fe compounds and determination of first shell radial distance

NASA Astrophysics Data System (ADS)

Parsai, Neetu; Mishra, Ashutosh

2017-05-01

X-ray absorption fine structure (XAFS) of some Fe compounds have been studied using the latest XAFS analysis software Demeter with Strawberry Perl. The processed XAFS data of the Fe compounds have been taken from available model compound library. The XAFS data have been processed to plot the µ(E) verses E spectra. These spectra have been converted into K-space, R-space and q-space. R-space spectra have been used to obtain first shell radial distance in Fe compounds. Structural parameters like first shell radial distance is useful in determination of bond length in Fe compounds. Hence the study play important role in biological applications.

Granulometric selectivity in Liza ramado and potential contamination resulting from heavy metal load in feeding areas

NASA Astrophysics Data System (ADS)

Pedro, Sílvia; Canastreiro, Vera; Caçador, Isabel; Pereira, Eduarda; Duarte, Armando C.; Raposo de Almeida, Pedro

2008-11-01

The stomach contents of thin-lipped grey mullets Liza ramado were analysed in terms of granulometric composition and compared to the sediment of potential feeding areas in the Tagus estuary. Total organic matter (TOM) content and heavy metal content were determined in the surface sediment of three areas and eight trace elements were quantified: Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn. The three sampled areas did not differ in TOM; and the heavy metal content was below Effects Range-Low level for most elements. The mean observed concentrations were present in the following sequence: Zn > Pb > Cr > Cu ≈ Ni > Co > Cd > Hg. Stomach contents granulometric composition provided information about the feeding selectivity of the mullets. Sediment fractions with particle size between 20 and 50 μm are preferred, independently of the fishes' length. Smaller standard length (SL) fishes have a higher positive selection of fine grained sediments than those with a larger SL. Finer fractions usually have higher concentration of heavy metals, which makes younger specimens of the thin-lipped grey mullet potentially more exposed to heavy metal load in the estuary. Metal concentration was not independent from the sampling point, presenting higher values near the margins and the estuary tidal drainage system. This means that during the first period of each tidal cycle, the mullets will feed first on the most contaminated areas, as a consequence of their movement following the rising tide to feed on previously exposed areas.

Identification of seven polyamine oxidase genes in tomato (Solanum lycopersicum L.) and their expression profiles under physiological and various stress conditions.

PubMed

Hao, Yanwei; Huang, Binbin; Jia, Dongyu; Mann, Taylor; Jiang, Xinyi; Qiu, Yuxing; Niitsu, Masaru; Berberich, Thomas; Kusano, Tomonobu; Liu, Taibo

2018-05-15

Polyamines (PAs) are implicated in developmental processes and stress responses of plants. Polyamine oxidases (PAOs), flavin adenine dinucleotide-dependent enzymes that function in PA catabolism, play a critical role. Even though PAO gene families of Arabidopsis and rice have been intensely characterized and their expression in response to developmental and environmental changes has been investigated, little is known about PAOs in tomato (Solanum lycopersicum). We found seven PAO genes in S. lycopersicum and named them SlPAO1∼7. Plant PAOs form four clades in phylogenetic analysis, of which SlPAO1 belongs to clade-I, SlPAO6 and SlPAO7 to clade-III, and the residual four (SlPAO2∼5) to clade-IV, while none belongs to clade-II. All the clade-IV members in tomato also retain the putative peroxisomal-targeting signals in their carboxy termini, suggesting their peroxisome localization. SlPAO1 to SlPAO5 genes consist of 10 exons and 9 introns, while SlPAO6 and SlPAO7 are intronless genes. To address the individual roles of SlPAOs, we analyzed their expression in various tissues and during flowering and fruit development. The expression of SlPAO2∼4 was constitutively high, while that of the other SlPAO members was relatively lower. We further analyzed the expressional changes of SlPAOs upon abiotic stresses, oxidative stresses, phytohormone application, and PA application. Based on the data obtained, we discuss the distinctive roles of SlPAOs. Copyright © 2018 Elsevier GmbH. All rights reserved.

Insights into the mechanisms of RNA secondary structure destabilization by the HIV-1 nucleocapsid protein

PubMed Central

Belfetmi, Anissa; Zargarian, Loussiné; Tisné, Carine; Sleiman, Dona; Morellet, Nelly; Lescop, Ewen; Maskri, Ouerdia; René, Brigitte; Mély, Yves; Fossé, Philippe; Mauffret, Olivier

2016-01-01

The mature HIV-1 nucleocapsid protein NCp7 (NC) plays a key role in reverse transcription facilitating the two obligatory strand transfers. Several properties contribute to its efficient chaperon activity: preferential binding to single-stranded regions, nucleic acid aggregation, helix destabilization, and rapid dissociation from nucleic acids. However, little is known about the relationships between these different properties, which are complicated by the ability of the protein to recognize particular HIV-1 stem–loops, such as SL1, SL2, and SL3, with high affinity and without destabilizing them. These latter properties are important in the context of genome packaging, during which NC is part of the Gag precursor. We used NMR to investigate destabilization of the full-length TAR (trans activating response element) RNA by NC, which is involved in the first strand transfer step of reverse transcription. NC was used at a low protein:nucleotide (nt) ratio of 1:59 in these experiments. NMR data for the imino protons of TAR identified most of the base pairs destabilized by NC. These base pairs were adjacent to the loops in the upper part of the TAR hairpin rather than randomly distributed. Gel retardation assays showed that conversion from the initial TAR–cTAR complex to the fully annealed form occurred much more slowly at the 1:59 ratio than at the higher ratios classically used. Nevertheless, NC significantly accelerated the formation of the initial complex at a ratio of 1:59. PMID:26826129

Radiocarbon dating of archaeological samples (sambaqui) using CO(2) absorption and liquid scintillation spectrometry of low background radiation.

PubMed

Mendonça, Maria Lúcia T G; Godoy, José M; da Cruz, Rosana P; Perez, Rhoneds A R

2006-01-01

Sambaqui means, in the Tupi language, a hill of shells. The sambaquis are archaeological sites with remains of pre-historical Brazilian occupation. Since the sambaqui sites in the Rio de Janeiro state region are older than 10,000 years, the applicability of CO(2) absorption on Carbo-sorb and (14)C determination by counting on a low background liquid scintillation counter was tested. In the present work, sambaqui shells were treated with H(3)PO(4) in a closed vessel in order to generate CO(2). The produced CO(2) was absorbed on Carbo-sorb. On saturation about 0.6g of carbon, as CO(2), was mixed with commercial liquid scintillation cocktail (Permafluor), and the (14)C activity determined by counting on a low background counter, Packard Tricarb 3170 TR/SL, for a period of 1000 mins to enable detection of a radiocarbon age of 22,400 BP. But only samples with ages up to 3500 BP were submitted to the method because the samples had been collected in the municipality of Guapimirim, in archaeological sambaqui-type sites belonging to this age range. The same samples were sent to the (14)C Laboratory of the Centro de Energia Nuclear na Agricultura (CENA/USP) where similar results were obtained.

Visual statistical learning is related to natural language ability in adults: An ERP study.

PubMed

Daltrozzo, Jerome; Emerson, Samantha N; Deocampo, Joanne; Singh, Sonia; Freggens, Marjorie; Branum-Martin, Lee; Conway, Christopher M

2017-03-01

Statistical learning (SL) is believed to enable language acquisition by allowing individuals to learn regularities within linguistic input. However, neural evidence supporting a direct relationship between SL and language ability is scarce. We investigated whether there are associations between event-related potential (ERP) correlates of SL and language abilities while controlling for the general level of selective attention. Seventeen adults completed tests of visual SL, receptive vocabulary, grammatical ability, and sentence completion. Response times and ERPs showed that SL is related to receptive vocabulary and grammatical ability. ERPs indicated that the relationship between SL and grammatical ability was independent of attention while the association between SL and receptive vocabulary depended on attention. The implications of these dissociative relationships in terms of underlying mechanisms of SL and language are discussed. These results further elucidate the cognitive nature of the links between SL mechanisms and language abilities. Copyright © 2017 Elsevier Inc. All rights reserved.

Visual statistical learning is related to natural language ability in adults: An ERP Study

PubMed Central

Daltrozzo, Jerome; Emerson, Samantha N.; Deocampo, Joanne; Singh, Sonia; Freggens, Marjorie; Branum-Martin, Lee; Conway, Christopher M.

2017-01-01

Statistical learning (SL) is believed to enable language acquisition by allowing individuals to learn regularities within linguistic input. However, neural evidence supporting a direct relationship between SL and language ability is scarce. We investigated whether there are associations between event-related potential (ERP) correlates of SL and language abilities while controlling for the general level of selective attention. Seventeen adults completed tests of visual SL, receptive vocabulary, grammatical ability, and sentence completion. Response times and ERPs showed that SL is related to receptive vocabulary and grammatical ability. ERPs indicated that the relationship between SL and grammatical ability was independent of attention while the association between SL and receptive vocabulary depended on attention. The implications of these dissociative relationships in terms of underlying mechanisms of SL and language are discussed. These results further elucidate the cognitive nature of the links between SL mechanisms and language abilities. PMID:28086142

Antioxidant effect of rosemary (Rosmarinus officinalis L.) extract in soybean lecithin-based semen extender following freeze-thawing process of ram sperm.

PubMed

Motlagh, Mahdi Khodaei; Sharafi, Mohsen; Zhandi, Mahdi; Mohammadi-Sangcheshmeh, Abdollah; Shakeri, Malak; Soleimani, Masoud; Zeinoaldini, Saeed

2014-10-01

The aim of current study was to evaluate effect of rosemary aqueous extract on post-thawed ram sperm quality in a soybean lecithin-based (SL) extender. Ram semen samples were obtained, extended with SL extender and supplemented with 0% (SL-R0), 2% (SL-R2), 4% (SL-R4), 6% (SL-R6), and 8% (SL-R8) rosemary aqueous extract. Following equilibration, the straws were frozen, and then plunged into the liquid nitrogen. After thawing, sperm motility and velocity parameters, plasma membrane functionality, viability, acrosomal and capacitation status were evaluated. Membrane lipid peroxidation was also analyzed through the malondialdehyde (MDA) concentration. Our results showed that SL-R4 and SL-R6 groups resulted in higher (p < 0.05) percentages of total motility, progressive motility, and plasma membrane functionality, as compared with other groups. Highest (p < 0.05) viable and lowest (p < 0.05) dead spermatozoa were observed in SL-R6 group compared to the other groups. The acrosomal and capacitation status were not affected (p > 0.05) by different levels of rosemary aqueous extract. Lower (p < 0.05) MDA concentration has been observed in SL-R4 and SL-R6 groups. The results of this study demonstrate that supplementation of SL extender with rosemary aqueous extract influences post-thawed ram sperm quality in a dose dependent manner. Copyright © 2014 Elsevier Inc. All rights reserved.

Impact of a nonuniform charge distribution on virus assembly

NASA Astrophysics Data System (ADS)

Li, Siyu; Erdemci-Tandogan, Gonca; Wagner, Jef; van der Schoot, Paul; Zandi, Roya

2017-08-01

Many spherical viruses encapsulate their genomes in protein shells with icosahedral symmetry. This process is spontaneous and driven by electrostatic interactions between positive domains on the virus coat proteins and the negative genomes. We model the effect of the nonuniform icosahedral charge distribution from the protein shell instead using a mean-field theory. We find that this nonuniform charge distribution strongly affects the optimal genome length and that it can explain the experimentally observed phenomenon of overcharging of virus and viruslike particles.

Anatomical structure of Camellia oleifera shell.

PubMed

Hu, Jinbo; Shi, Yang; Liu, Yuan; Chang, Shanshan

2018-06-04

The main product of Camellia oleifera is edible oil made from the seeds, but huge quantities of agro-waste are produced in the form of shells. The primary components of C. oleifera fruit shell are cellulose, hemicellulose, and lignin, which probably make it a good eco-friendly non-wood material. Understanding the structure of the shell is however a prerequisite to making full use of it. The anatomical structure of C. oleifera fruit shells was investigated from macroscopic to ultrastructural scale by stereoscopic, optical, and scanning electron microscopy. The main cell morphology in the different parts of the shell was observed and measured using the tissue segregation method. The density of the cross section of the shell was also obtained using an X-ray CT scanner to check the change in texture. The C. oleifera fruit pericarp was made up of exocarp, mesocarp, and endocarp. The main types of exocarp cells were stone cells, spiral vessels, and parenchyma cells. The mesocarp accounted for most of the shell and consisted of parenchyma, tracheids, and some stone cells. The endocarp was basically made up of cells with a thickened cell wall that were modified tracheid or parenchyma cells with secondary wall thickening. The most important ultrastructure in these cells was the pits in the cell wall of stone and vessel cells that give the shell a conducting, mechanical, and protective role. The density of the shell gradually decreased from exocarp to endocarp. Tracheid cells are one of the main cell types in the shell, but their low slenderness (length to width) ratio makes them unsuitable for the manufacture of paper. Further research should be conducted on composite shell-plastic panels (or other reinforced materials) to make better use of this agro-waste.

On the Transition from Initial Leader to Stepped Leader in Negative Cloud-to-ground Lightning

NASA Astrophysics Data System (ADS)

Stolzenburg, M.; Marshall, T. C.; Karunarathne, S.; Orville, R. E.

2017-12-01

High-speed video and electric field change (E-change) data are used to describe the first 5 ms of a natural negative cloud-to-ground (CG) flash. These observations reveal differences in appearance of both the video luminosity and the E-change pulses before the leader transitions to propagating as a negative stepped leader (SL). During the initial breakdown (IB) stage, the initial leader advances intermittently forward in jumps of 78-175 m, at intervals of 100-280 μs, and in separate bursts that are bright for a few 20-μs video frames. The IB pulses accompanying these luminosity bursts have long duration, large amplitude, and a characteristic bipolar shape in nearby E-change observations. In the time between IB pulses, the initial leader is very dim or not visible during the earliest 1-2 ms of the IB stage. Over the next few milliseconds, the leader propagation transitions to an early SL phase, in which the leader tips advance 20-59 m forward at more regular intervals of 40-80 μs during relatively dim and brief steps. In the E-change data, the accompanying SL pulses have very short duration, small amplitude, and are typically unipolar. These data indicate that when the entire initial leader length behind the lower end begins to remain illuminated between bursts, the propagation mode changes from IB bursts to SL steps, and the IB stage ends. Additional differences in initial leader character are evident during the return stroke, as its luminosity speed decreases sharply upon reaching the topmost initial leader section of the channel, and that section of channel does not saturate the video intensity. Results of these analyses support a prior hypothesis that the early initial leader development occurs in the absence of a continuously hot channel, and consequently, the initial leader propagation is unlike the self-propagating advance of the later stepped leader.

Size-related mortality due to gnathiid isopod micropredation correlates with settlement size in coral reef fishes

NASA Astrophysics Data System (ADS)

Grutter, A. S.; Blomberg, S. P.; Fargher, B.; Kuris, A. M.; McCormick, M. I.; Warner, R. R.

2017-06-01

The transition between the planktonic and the benthic habitat is a critical period for the larvae of many demersal marine organisms. Understanding the potential constraints on the timing of this habitat transition, called settlement, is important to understanding their biology. Size-specific mortality can set the limits on lifestyle and help explain ontogenetic habitat shifts. We examined whether size-based mortality risks after settlement may include micropredation by ectoparasites by testing whether survival of settlement-stage fish varies with fish size when exposed to a reef-associated micropredator. Fish (14 species) were exposed to one blood-sucking gnathiid isopod overnight, with appropriate controls; gnathiid feeding success and survival, and fish mortality were recorded relative to fish size. After adjusting for fish relatedness, we found the relationship between fish mortality and size differed with gnathiid exposure: for gnathiid-exposed fish, the mean mortality of the smallest fish was much higher (57%) than unexposed controls (10%), and decreased to 0% for fish >12 mm standard length (SL); mortality was almost nil in controls. Thus, a predicted optimal size to switch habitat and reduce mortality risk from micropredation should be >12 mm SL. We then asked what species might be at greater risk and if the steep increase in survival at 12 mm SL might coincide with settlement at larger sizes among fishes. Across 102 other species (32 families), 61% settled at ≥12 mm SL. After adjusting for relatedness, mean fish settlement size was 15.0 mm and this was not significantly different from 12 mm. Thus, settlement size clusters around the minimum fish size threshold our gnathiid experiment predicted would be large enough to survive a gnathiid encounter. These results suggest micropredators may contribute to size-selective mortality during settlement processes and are consistent with the hypothesis that the pelagic phase provides fish an escape from certain micropredators.

Effects of a structured midsole on spatio-temporal variables and running economy in overground running.

PubMed

Wunsch, Tobias; Kröll, Josef; Stöggl, Thomas; Schwameder, Hermann

2017-04-01

Research to enhance running performance has led to the design of a leaf spring-structured midsole shoe (LEAF). In treadmill running, it has been shown that LEAF led to an increased running economy and increased stride length (SL) through a horizontal foot shift during stance compared to a standard foam shoe (FOAM). The purpose of this study was to analyse whether (a) these findings can also be observed in overground running and (b) relations exist between spatio-temporal variables and running economy. Ten male long-distance heel-strike runners ran at their individual 2 mmol/l blood lactate speed with LEAF and FOAM in randomized order. Kinematic data were recorded with an inertial measurement unit synchronized with 2D video. Oxygen consumption was measured using an automated metabolic gas analysis system. Blood lactate was collected after each run. The strike pattern was unaffected by LEAF. SL was increased by 0.9 ± 1.1 cm (95% CI 0.2 to 1.5; p = .040; d z  = 0.76), stride rate (SR) was reduced by -0.4 ± 0.3 strides/min (95% CI -0.6 to -0.1; p = .029; d z  = 0.82) and oxygen consumption tended to be reduced by 1% (-0.4 ± 0.6 ml/min/kg; 95% CI -0.8 to 0.0; p = .082; d z  = 0.62) when running with LEAF compared to FOAM. Changes in oxygen consumption in LEAF were correlated with SL (r = 0.71; p = .022) and SR (r = -0.68; p = .031). It can be concluded that LEAF has the potential to cause small changes in spatio-temporal variables during running. Runners increasing SL and decreasing SR in response to LEAF can achieve small improvements in running economy, which is beneficial in terms of performance.

Allometric growth and development of organs in ballan wrasse (Labrus bergylta Ascanius, 1767) larvae in relation to different live prey diets and growth rates

PubMed Central

Wold, Per-Arvid; Bardal, Tora; Øie, Gunvor; Kjørsvik, Elin

2016-01-01

ABSTRACT Small fish larvae grow allometrically, but little is known about how this growth pattern may be affected by different growth rates and early diet quality. The present study investigates how different growth rates, caused by start-feeding with copepods or rotifers the first 30 days post-hatch (dph), affect allometric growth and development of nine major organs in ballan wrasse (Labrus bergylta) larvae up to experimental end at 60 dph. Feeding with cultivated copepod nauplii led to both increased larval somatic growth and faster development and growth of organ systems than feeding with rotifers. Of the organs studied, the digestive and respiratory organs increased the most in size between 4 and 8 dph, having a daily specific growth rate (SGR) between 30 and 40% in larvae fed copepods compared with 20% or less for rotifer-fed larvae. Muscle growth was prioritised from flexion stage and onwards, with a daily SGR close to 30% between 21 and 33 dph regardless of treatment. All larvae demonstrated a positive linear correlation between larval standard length (SL) and increase in total tissue volume, and no difference in allometric growth pattern was found between the larval treatments. A change from positive allometric to isometric growth was observed at a SL close to 6.0 mm, a sign associated with the start of metamorphosis. This was also where the larvae reached postflexion stage, and was accompanied by a change in growth pattern for most of the major organ systems. The first sign of a developing hepatopancreas was, however, first observed in the largest larva (17.4 mm SL, 55 dph), indicating that the metamorphosis in ballan wrasse is a gradual process lasting from 6.0 to at least 15-17 mm SL. PMID:27422903

A Universal Stress Protein Involved in Oxidative Stress Is a Phosphorylation Target for Protein Kinase CIPK61

PubMed Central

2017-01-01

Calcineurin B-like interacting protein kinases (CIPKs) decode calcium signals upon interaction with the calcium sensors calcineurin B like proteins into phosphorylation events that result into adaptation to environmental stresses. Few phosphorylation targets of CIPKs are known and therefore the molecular mechanisms underlying their downstream output responses are not fully understood. Tomato (Solanum lycopersicum) Cipk6 regulates immune and susceptible Programmed cell death in immunity transforming Ca2+ signals into reactive oxygen species (ROS) signaling. To investigate SlCipk6-induced molecular mechanisms and identify putative substrates, a yeast two-hybrid approach was carried on and a protein was identified that contained a Universal stress protein (Usp) domain present in bacteria, protozoa and plants, which we named “SlRd2”. SlRd2 was an ATP-binding protein that formed homodimers in planta. SlCipk6 and SlRd2 interacted using coimmunoprecipitation and bimolecular fluorescence complementation (BiFC) assays in Nicotiana benthamiana leaves and the complex localized in the cytosol. SlCipk6 phosphorylated SlRd2 in vitro, thus defining, to our knowledge, a novel target for CIPKs. Heterologous SlRd2 overexpression in yeast conferred resistance to highly toxic LiCl, whereas SlRd2 expression in Escherichia coli UspA mutant restored bacterial viability in response to H2O2 treatment. Finally, transient expression of SlCipk6 in transgenic N. benthamiana SlRd2 overexpressors resulted in reduced ROS accumulation as compared to wild-type plants. Taken together, our results establish that SlRd2, a tomato UspA, is, to our knowledge, a novel interactor and phosphorylation target of a member of the CIPK family, SlCipk6, and functionally regulates SlCipk6-mediated ROS generation. PMID:27899535

SL-01, an oral derivative of gemcitabine, inhibited human breast cancer growth through induction of apoptosis

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

Li, Yuan-Yuan; Qin, Yi-Zhuo; Wang, Rui-Qi

Highlights: •SL-01 is an oral derivative of gemcitabine. •SL-01 possessed activity against human breast cancer growth via apoptotic induction. •SL-01’s activity was more potently than that of gemcitabine. •SL-01 inhibited cancer growth without toxicity to mice. -- Abstract: SL-01 is an oral derivative of gemcitabine that was synthesized by introducing the moiety of 3-(dodecyloxycarbonyl) pyrazine-2-carbonyl at N4-position on cytidine ring of gemcitabine. We aimed to evaluate the efficacy of SL-01 on human breast cancer growth. SL-01 significantly inhibited MCF-7 proliferation as estimated by colorimetric assay. Flow cytometry assay indicated the apoptotic induction and cell cycle arrest in G1 phase. SL-01more » modulated the expressions of p-ATM, p53 and p21 and decrease of cyclin D1 in MCF-7 cells. Further experiments were performed in a MCF-7 xenografts mouse model. SL-01 by oral administration strongly inhibited MCF-7 xenografts growth. This effect of SL-01 might arise from its roles in the induction of apoptosis. Immunohistochemistry assay showed the increase of TUNEL staining cells. Western blotting indicated the modulation of apoptotic proteins in SL-01-treated xenografts. During the course of study, there was no evidence of toxicity to mice. In contrast, the decrease of neutrophil cells in peripheral and increase of AST and ALT levels in serum were observed in the gemcitabine-treated mice. Conclusion: SL-01 possessed similar activity against human breast cancer growth with gemcitabine, whereas, with lower toxicity to gemcitabine. SL-01 is a potent oral agent that may supplant the use of gemcitabine.« less

A Universal Stress Protein Involved in Oxidative Stress Is a Phosphorylation Target for Protein Kinase CIPK6.

PubMed

Gutiérrez-Beltrán, Emilio; Personat, José María; de la Torre, Fernando; Del Pozo, Olga

2017-01-01

Calcineurin B-like interacting protein kinases (CIPKs) decode calcium signals upon interaction with the calcium sensors calcineurin B like proteins into phosphorylation events that result into adaptation to environmental stresses. Few phosphorylation targets of CIPKs are known and therefore the molecular mechanisms underlying their downstream output responses are not fully understood. Tomato (Solanum lycopersicum) Cipk6 regulates immune and susceptible Programmed cell death in immunity transforming Ca 2+ signals into reactive oxygen species (ROS) signaling. To investigate SlCipk6-induced molecular mechanisms and identify putative substrates, a yeast two-hybrid approach was carried on and a protein was identified that contained a Universal stress protein (Usp) domain present in bacteria, protozoa and plants, which we named "SlRd2". SlRd2 was an ATP-binding protein that formed homodimers in planta. SlCipk6 and SlRd2 interacted using coimmunoprecipitation and bimolecular fluorescence complementation (BiFC) assays in Nicotiana benthamiana leaves and the complex localized in the cytosol. SlCipk6 phosphorylated SlRd2 in vitro, thus defining, to our knowledge, a novel target for CIPKs. Heterologous SlRd2 overexpression in yeast conferred resistance to highly toxic LiCl, whereas SlRd2 expression in Escherichia coli UspA mutant restored bacterial viability in response to H 2 O 2 treatment. Finally, transient expression of SlCipk6 in transgenic N benthamiana SlRd2 overexpressors resulted in reduced ROS accumulation as compared to wild-type plants. Taken together, our results establish that SlRd2, a tomato UspA, is, to our knowledge, a novel interactor and phosphorylation target of a member of the CIPK family, SlCipk6, and functionally regulates SlCipk6-mediated ROS generation. © 2017 American Society of Plant Biologists. All Rights Reserved.

Fruit-localized Phytochromes Regulate Plastid Biogenesis, Starch Synthesis and Carotenoid Metabolism in Tomato.

PubMed

Ernesto Bianchetti, Ricardo; Silvestre Lira, Bruno; Santos Monteiro, Scarlet; Demarco, Diego; Purgatto, Eduardo; Rothan, Christophe; Rossi, Magdalena; Freschi, Luciano

2018-04-18

Light signaling has long been reported to influence fruit biology, though the regulatory impact of fruit-localized photoreceptors on fruit development and metabolism remains elusive. Studies performed in phytochrome(PHY)-deficient tomato (Solanum lycopersicum) mutants suggest that SlPHYA, SlPHYB2 and to a lesser extent SlPHYB1 influence fruit development and ripening. By employing fruit-specific RNAi-mediated silencing of SlPHY genes, we demonstrated that fruit-localized SlPHYA and SlPHYB2 play contrasting roles in regulating plastid biogenesis and maturation in tomato. Data revealed that fruit-localized SlPHYA, rather than SlPHYB1 or SlPHYB2, positively influence tomato plastid differentiation and division machinery via changes in both light and cytokinin signaling-related gene expression. Fruit-localized SlPHYA and SlPHYB2 were also shown to modulate sugar metabolism in early developing fruits via overlapping, yet distinct, mechanisms involving the coordinated transcriptional regulation of sink- and starch biosynthesis-related genes. Fruit-specific SlPHY silencing also drastically altered the transcriptional profile of genes encoding light repressor proteins and carotenoid biosynthesis regulators, leading to reduced carotenoid biosynthesis during fruit ripening. Therefore, besides providing conclusive evidence on the regulation of tomato quality by fruit-localized phytochromes, our data also demonstrate the existence of an intricate PHY-hormonal interplay during fruit development and ripening.

Pb(core)/ZnO(shell) nanowires obtained by microwave-assisted method

PubMed Central

2011-01-01

In this study, Pb-filled ZnO nanowires [Pb(core)/ZnO(shell)] were synthesized by a simple and novel one-step vapor transport and condensation method by microwave-assisted decomposition of zinc ferrite. The synthesis was performed using a conventional oven at 1000 W and 5 min of treatment. After synthesis, a spongy white cotton-like material was obtained in the condensation zone of the reaction system. HRTEM analysis revealed that product consists of a Pb-(core) with (fcc) cubic structure that preferentially grows in the [111] direction and a hexagonal wurtzite ZnO-(Shell) that grows in the [001] direction. Nanowire length was more than 5 μm and a statistical analysis determined that the shell and core diameters were 21.00 ± 3.00 and 4.00 ± 1.00 nm, respectively. Experimental, structural details, and synthesis mechanism are discussed in this study. PMID:21985637

Investigation of CuInSe2 nanowire arrays with core-shell structure electrodeposited at various duty cycles into anodic alumina templates

NASA Astrophysics Data System (ADS)

Cheng, Yu-Song; Wang, Na-Fu; Tsai, Yu-Zen; Lin, Jia-Jun; Houng, Mau-Phon

2017-02-01

Copper indium selenide (CuInSe2) nanowire (NW) arrays were prepared at various electrolyte duty cycles by filling anodic alumina templates through the pulsed electrodeposition technique. X-ray diffraction and scanning electron microscopy (SEM) images showed that the nucleation mechanism of CuInSe2 NW arrays was affected by the electrodeposition duty cycle. Moreover, SEM images showed that the diameter and length of the NWs were 80 nm and 2 μm, respectively. Furthermore, PEDOT/CuInSe2 NW core-shell arrays were fabricated using surfactant-modified CuInSe2 NW surfaces showing the lotus effect. Transmission electron microscopy images confirmed that a core-shell structure was achieved. Current-voltage plots revealed that the CuInSe2 NW arrays were p-type semiconductors; moreover, the core-shell structure improved the diode ideality factor from 3.91 to 2.63.

Identification and characterization of thermotolerant acetic acid bacteria strains isolated from coconut water vinegar in Sri Lanka.

PubMed

Perumpuli, P A B N; Watanabe, Taisuke; Toyama, Hirohide

2014-01-01

From the pellicle formed on top of brewing coconut water vinegar in Sri Lanka, three Acetobacter strains (SL13E-2, SL13E-3, and SL13E-4) that grow at 42 °C and four Gluconobacter strains (SL13-5, SL13-6, SL13-7, and SL13-8) grow at 37 °C were identified as Acetobacter pasteurianus and Gluconobacter frateurii, respectively. Acetic acid production by the isolated Acetobacter strains was examined. All three strains gave 4% acetic acid from 6% initial ethanol at 37 °C, and 2.5% acetic acid from 4% initial ethanol at 40 °C. Compared with the two other strains, SL13E-4 showed both slower growth and slower acetic acid production. As well as the thermotolerant SKU1108 strain, the activities of the alcohol dehydrogenase and the aldehyde dehydrogenase of SL13E-2 and SL13E-4 were more stable than those of the mesophilic strain. The isolated strains were used to produce coconut water vinegar at higher temperatures than typically used for vinegar production.

Surface Layer Matrix-Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (SL-MALDI-ToF-MS) Analysis of Polymer Blend Surface Composition

NASA Astrophysics Data System (ADS)

Hill, Jacob A.

The composition of a polymer blend is generally different at the surface than in the bulk and the gradient in composition with depth has important implications for surface properties. The determination of the surface composition presents various challenges which continue to prompt the development of new techniques for quantifying the composition. Here the technique of surface layer matrix-assisted laser desorption ionization time-of-flight mass spectrometry (SL-MALDI-ToF-MS) has been further developed to address four specific questions of polymer blend surface behavior within the general category of surface composition determination. The first question is how chain length disparity affects surface segregation in the case that the disparity is quite small. While such segregation is known for blends containing low molecular weight additives or systems with large polydispersity, it has not been reported for anionically polymerized polymers that are viewed, in practice, as monodisperse. For 6 kDa polystyrene the number average molecular weight (Mn) at the surface is ca. 300 Da (5%) lower than that in the bulk and for 7 kDa polymethyl methacrylate the shift is ca. 500 Da. The second question is how chain-end functionalization effects not the location of chain ends at the surface, but rather the prevalence at the surface of any part of a chain having an end functionalization. A key issue of such an approach is understanding precisely where the functionalities ultimately reside and how this functionalization shifts the balance of forces that determine the distribution of chains with depth. The surface of a blend of 6 kDa polystyrene and 6 kDa polystyrene functionalized with hydroxymethyl ends is not only depleted of the higher energy end groups, but is depleted of any segments belonging to the functionalized chains. This is demonstrated using SL-MALDI-ToF-MS, which detects entire chains that have any repeat unit at the outer surface, and requires no labelling. This study was extended to the surfaces of blends of 6 kDa polystyrene and 6 kDa polystyrene functionalized with hydroxyethyl ends. Blends of all compositions less than 90 wt. % functionalized chains showed depletion. Finally, the challenge of determining lateral variations in the surface composition has been addressed with the development of SL-MALDI-ToF-MS imaging (SL-MALDI-ToF-MSI). Key to developing imaging capability was improving the lateral uniformity of the matrix deposition. This uniformity was achieved using solvent free sublimation of matrix and salt onto the sample's surface. The capabilities of SL-MALDI-ToF-MSI were demonstrated by imaging the absence of material due to masking during material deposition, mechanical scribing or solvent perturbation at the surface of low molecular weight poly(methyl methacrylate) and polystyrene thin films. SL-MALDI-ToF MSI was made possible through the first uniform, solvent free simultaneous sublimation of matrix and salt onto the material's surface.

Intra-specific diet shift in manila clams (Ruditapes philippinarum) as revealed by carbon and nitrogen stable isotopes and fatty acid biomarker

NASA Astrophysics Data System (ADS)

Suh, Y.; Shin, K.

2011-12-01

Manila clams sampled in Seonjae Island, Korea with shell lengths (SL) below 19.76 mm in average showed a significantly depleted carbon and nitrogen isotope values (P<0.05) by 0.80~1.41 %. This size related variation can be caused by either altered carbon and nutrient source or by affected isotopic incorporation rates and discrimination factors. In order to examine size-related diet shift in manila clams, R. philippinarum with different sizes that were constantly fed on known mixed microalgae for several months were sampled from Incheon Fisheries Hacheries Research Institute (IFRI). These manila clams have shown a high intra-species variation in growth rate with a maximum difference of more or less 2.30 cm. The smallest size groups (3.68±0.17 mm and 6.88±0.21 mm) obtained their nutrition from both P. tricornutum and aggregated organic matter that consists of dead or decomposed microalgae or other detritus. Bigger size groups (10.92±0.34 mm and 14.81±0.25 mm) obtained most of their energy from P.tricorutum and also from other phytoplankton unlike the biggest size group (21.15±1.02 mm) that feeds mainly on fresh microalgae of all diets fed. This variation in diet reveals that smaller clams mostly inhale dead or decomposed microalgae that sinks on the bottom while the bigger clams uptake more fresh ones that are still alive. This variation in feeding behavior could have been caused by morphological constraints such as limited siphon length. The results suggest that manila clams greater than and below 19.76 mm in average have different feeding behavior and P. tricornutum and I. galbana were the two most preferred diets for manila clams cultured in IFHRI. The result of fatty acid composition of manila clams in relation to size or growth rate suggests that fast growing clams would have rapid metabolism of fatty acids not required by the animals and an accumulation of the essential fatty acids (PUFA). In addition, their higher energy requirement and more active state of development would further diminish lipid reserve of the species.

SL-01, an oral gemcitabine derivative, inhibited human cancer growth more potently than gemcitabine

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

Zhao, Cuirong; Yue, Bin; Liu, Huiping

2012-08-01

SL-01, an oral gemcitabine derivative, was synthesized by introducing the moiety of 3-(dodecyloxycarbonyl)pyrazine-2-carbonyl at the N4-position on the cytidine ring of gemcitabine. Our goal in this study was to evaluate the efficacy of SL-01 on the growth of human cancers with gemcitabine as control. Experiments were performed on human non-small cell lung cancer NCI-H460 and colon cancer HCT-116 both in vitro and in vivo. In vitro assays, SL-01 significantly inhibited the growth of cancer cells as determined by the 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay. Further studies indicated that SL-01 induced the cancer cells to apoptosis showing chromatin condensation andmore » externalization of phosphatidylserine. In in vivo studies, we evaluated the efficacy of SL-01 in nude mice bearing human cancer xenografts. SL-01 effectively delayed the growth of NCI-H460 and HCT-116 without significant loss of body weight. Molecular analysis indicated that the high efficacy of SL-01 was associated with its ability to induce apoptosis as evidenced by increase of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining cells, activation of caspase-9, caspase-3 and cleaved poly ADP-ribose polymerase (PARP) in tumor tissues. SL-01 also increased Bax/Bcl-2 ratio in cancer cells. These biological activities of SL-01 were more potential than that of gemcitabine. Based on these in vitro and in vivo results, SL-01 is proposed as a potent oral anticancer agent that may supplant the use of gemcitabine in the clinic. -- Highlights: ► An oral gemcitabine derivative SL-01 was synthesized. ► The effects of SL-01 were evaluated and its efficacy was compared with gemcitabine. ► The biological activities of SL-01 were more potent than that of gemcitabine. ► SL-01 could replace gemcitabine for clinical use.« less

[Conversion methods of freshwater snail tissue dry mass and ash free dry mass].

PubMed

Zhao, Wei-Hua; Wang, Hai-Jun; Wang, Hong-Zhu; Liu, Xue-Qin

2009-06-01

Mollusk biomass is usually expressed as wet mass with shell, but this expression fails to represent real biomass due to the high calcium carbonate content in shells. Tissue dry mass and ash free dry mass are relatively close to real biomass. However, the determination process of these two parameters is very complicated, and thus, it is necessary to establish simple and practical conversion methods for these two parameters. A total of six taxa of freshwater snails (Bellamya sp., Alocinma longicornis, Parafossarulus striatulus, Parafossarulus eximius, Semisulcospira cancellata, and Radix sp.) common in the Yangtze Basin were selected to explore the relations of their five shell dimension parameters, dry and wet mass with shells with their tissue dry mass and ash free dry mass. The regressions of the tissue dry mass and ash free dry mass with the five shell dimension parameters were all exponential (y = ax(b)). Among them, shell width and shell length were more precise (the average percentage error between observed and predicted value being 22.0% and 22.5%, respectively) than the other three parameters in the conversion of dry mass. Wet mass with shell could be directly converted to tissue dry mass and ash free dry mass, with an average percentage error of 21.7%. According to the essence of definition and the errors of conversion, ash free dry mass would be the optimum parameter to express snail biomass.

Retrieval of Missing Spliced Leader in Dinoflagellates

PubMed Central

Zhang, Huan; Lin, Senjie

2009-01-01

Spliced leader (SL) trans-splicing has recently been shown to be a common mRNA processing mechanism in dinoflagellates, in which a short (22-nt) sequence, DCCGUAGCCAUUUUGGCUCAAG (D = U, A, or G), is transplanted from the 5′-end of a small non-coding RNA (SL RNA) to the 5′ end of mRNA molecules. The widespread existence of the mechanism in dinoflagellates has been demonstrated by detection of this SL (DinoSL) in a wide phylogenetic range of dinoflagellates. Furthermore, the presence of DinoSL in the transcripts of highly diverse groups of nuclear-encoded genes has led us to postulate that SL trans-splicing is universal in dinoflagellate nuclear genome. However, some observations inconsistent to this postulation have been reported, exemplified by a recent article reporting apparent absence of DinoSL in the transcripts of some nuclear-encoded genes in Amphidinium carterae. Absence of SL in these gene transcripts would have important implication on gene regulation in dinoflagellates and utility of DinoSL as a universal dinoflagellate-specific primer to study dinoflagellate transcriptomics. In this study, we re-examined transcripts of these genes and found that all of them actually contained DinoSL. Therefore, results to date are consistent to our initial postulation that DinoSL occurs in all dinoflagellate nuclear-encoded mRNAs. PMID:19122814

[Growth of Strombus gigas (Gastropoda: Strombidae) snail in 4 environments of Quintana Roo, Mexico].

PubMed

Navarrete, A J

2001-03-01

The growth rate of queen conch cultured in pens was studied from October 1993 to March 1994. Sixteen pens (50 m2 each, four pens per environment), were set in four environments: Thalassia, Thalassia-sand, Sand and Coral within a reef lagoon on Punta Gavilan and Banco Chinchorro. Twenty conchs were introduced in each pen (sizes: 100-120, 120-140, 140-160 and 160-180 mm shell length) and measured monthly to the nearest mm. Growth rate was assessed by two methods: a) shell marginal mean increase and b) the Gulland-Holt method considering all conch within pens. In the first method, the environment Sand had the highest growth (3.21 +/- 0.26 mm/month) at Punta Gavilan, whereas at Banco Chinchorro, highest growth was recorded in Coral (2.31 +/- 0.44 mm/month). Considering the second method, highest asymptotic length conch in Punta Gavilan occurred in Thalassia-sand (287.5 mm), whereas in Banco Chinchorro the highest asymptotic length was measured in Sand (318.1 mm). There were significant differences in growth between sites; juvenile growth is related with habitat quality mainly food availability.

Hard clam walking: Active horizontal locomotion of adult Mercenaria mercenaria at the sediment surface and behavioral suppression after extensive sampling

PubMed Central

Europe, James R.; Tettelbach, Christian R. H.; Havelin, Jason; Rodgers, Brooke S.; Furman, Bradley T.; Velasquez, Marissa

2017-01-01

Locomotion of infaunal bivalve mollusks primarily consists of vertical movements related to burrowing; horizontal movements have only been reported for a few species. Here, we characterize hard clam walking: active horizontal locomotion of adults (up to 118 mm shell length, SL) of the commercially important species, Mercenaria mercenaria, at the sediment surface—a behavior only briefly noted in the literature. We opportunistically observed walking over a 10-yr period, at 9 different sites in the Peconic Bays, New York, USA, and tested several hypotheses for the underlying cause of this behavior through quantitative field sampling and reproductive analyses. Hard clam walking was exhibited by males and females at equal frequency, predominantly during June/July and October, when clams were in peak spawning condition. Extensive walking behavior appears to be cued by a minimum population density; we suggest it may be mediated by unidentified pheromone(s), infaunal pressure waves and/or other unidentified factors. There was no directionality exhibited by walking clams, but individuals in an area of extensive walking were highly aggregated and walking clams were significantly more likely to move toward a member of the opposite sex. Thus, we conclude that hard clam walking serves to aggregate mature individuals prior to spawning, thereby facilitating greater fertilization success. In the process of investigating this behavior, however, we apparently oversampled one population and reduced clam densities below the estimated minimum threshold density and, in so doing, suppressed extensive walking for a period of >3 years running. This not only reinforces the importance of detailed field investigations of species biology and ecology, even for those that are considered to be well studied, but also highlights the need for greater awareness of the potential for research activities to affect focal species behavior. PMID:28278288

Swimming of a Sea Butterfly with an Elongated Shell

NASA Astrophysics Data System (ADS)

Karakas, Ferhat; Maas, Amy E.; Murphy, David W.

2017-11-01

Sea butterflies (pteropods) are small, zooplanktonic marine snails which swim by flapping highly flexible parapodia. Previous studies show that the swimming hydrodynamics of Limacina helicina, a polar pteropod with a spiraled shell, is similar to tiny insect flight aerodynamics and that forward-backward pitching is key for lift generation. However, swimming by diverse pteropod species with different shell shapes has not been examined. We present measurements of the swimming of Cuvierina columnella, a warm water species with an elongated non-spiraled shell collected off the coast of Bermuda. With a body length of 9 mm, wing beat frequency of 4-6 Hz and swimming speed of 35 mm/s, these organisms swim at a Reynolds number of approximately 300, larger than that of L. helicina. High speed 3D kinematics acquired via two orthogonal cameras reveals that the elongated shell correlates with reduced body pitching and that the wings bend approximately 180 degrees in each direction, overlapping at the end of each half-stroke. Time resolved 2D flow measurements collected with a micro-PIV system reveal leading edge vortices present in both power and recovery strokes. Interactions between the overlapping wings and the shell also likely play a role in lift generation.

Nonpolar InGaN/GaN Core-Shell Single Nanowire Lasers.

PubMed

Li, Changyi; Wright, Jeremy B; Liu, Sheng; Lu, Ping; Figiel, Jeffrey J; Leung, Benjamin; Chow, Weng W; Brener, Igal; Koleske, Daniel D; Luk, Ting-Shan; Feezell, Daniel F; Brueck, S R J; Wang, George T

2017-02-08

We report lasing from nonpolar p-i-n InGaN/GaN multi-quantum well core-shell single-nanowire lasers by optical pumping at room temperature. The nanowire lasers were fabricated using a hybrid approach consisting of a top-down two-step etch process followed by a bottom-up regrowth process, enabling precise geometrical control and high material gain and optical confinement. The modal gain spectra and the gain curves of the core-shell nanowire lasers were measured using micro-photoluminescence and analyzed using the Hakki-Paoli method. Significantly lower lasing thresholds due to high optical gain were measured compared to previously reported semipolar InGaN/GaN core-shell nanowires, despite significantly shorter cavity lengths and reduced active region volume. Mode simulations show that due to the core-shell architecture, annular-shaped modes have higher optical confinement than solid transverse modes. The results show the viability of this p-i-n nonpolar core-shell nanowire architecture, previously investigated for next-generation light-emitting diodes, as low-threshold, coherent UV-visible nanoscale light emitters, and open a route toward monolithic, integrable, electrically injected single-nanowire lasers operating at room temperature.

Nonpolar InGaN/GaN core–shell single nanowire lasers

DOE PAGES

Li, Changyi; Wright, Jeremy Benjamin; Liu, Sheng; ...

2017-01-24

We report lasing from nonpolar p-i-n InGaN/GaN multi-quantum well core–shell single-nanowire lasers by optical pumping at room temperature. The nanowire lasers were fabricated using a hybrid approach consisting of a top-down two-step etch process followed by a bottom-up regrowth process, enabling precise geometrical control and high material gain and optical confinement. The modal gain spectra and the gain curves of the core–shell nanowire lasers were measured using micro-photoluminescence and analyzed using the Hakki-Paoli method. Significantly lower lasing thresholds due to high optical gain were measured compared to previously reported semipolar InGaN/GaN core–shell nanowires, despite significantly shorter cavity lengths and reducedmore » active region volume. Mode simulations show that due to the core–shell architecture, annular-shaped modes have higher optical confinement than solid transverse modes. Furthermore, the results show the viability of this p-i-n nonpolar core–shell nanowire architecture, previously investigated for next-generation light-emitting diodes, as low-threshold, coherent UV–visible nanoscale light emitters, and open a route toward monolithic, integrable, electrically injected single-nanowire lasers operating at room temperature.« less

[Gonadal ontogenesis and sex differentiation in the sea bass, Dicentrarchus labrax, under fish-farming conditions].

PubMed

Roblin, C; Bruslé, J

1983-01-01

The histology of the different stages of gonadal development (appearance of PGC, edification of gonad primordium, organization of an undifferentiated gonad, testicular or ovarian development) has been studied in fingerlings and juveniles of sea-bass in fish-culture conditions. Sex differentiation with a caudo-cranial gradient was direct and more in accordance with length than with age. Ovarian and testicular differentiation occurred in fish 11 to 23 months old and from 90 to 187 mm SL. Testis ova were frequently observed.

CORRIGENDUM: Universal variational expansion for high-precision bound-state calculations in three-body systems. Applications to weakly bound, adiabatic and two-shell cluster systems

NASA Astrophysics Data System (ADS)

Bailey, David H.; Frolov, Alexei M.

2003-12-01

Since the above paper was published we have received a suggestion from T K Rebane that our variational energy, -402.261 928 652 266 220 998 au, for the 3S(L = 0) state from table 4 (right-hand column) is wrong in the fourth and fifth decimal digits. Our original variational energies were E(2000) = -402.192 865 226 622 099 583 au and E(3000) = -402.192 865 226 622 099 838 au. Unfortunately, table 4 contains a simple typographic error. The first two digits after the decimal point (26) in the published energies must be removed. Then the results exactly coincide with the original energies. These digits (26) were left in table 4 from the original version, which also included the 2S(L = 0) states of the helium-muonic atoms. A similar typographic error was found in table 4 of another paper by A M Frolov (2001 J. Phys. B: At. Mol. Opt. Phys. 34 3813). The computed ground state energy for the ppµ muonic molecular ion was -0.494 386 820 248 934 546 94 mau. In table 4 of that paper the first figure '8' (fifth digit after the decimal point) was lost from the energy value presented in this table. We wish to thank T K Rebane of the Fock Physical Institute in St Petersburg for pointing out the misprint related to the helium(4)-muonic atom.

Reproductive characteristics of the humbug damselfish, Dascyllus aruanus, in Chuuk Lagoon, Micronesia

NASA Astrophysics Data System (ADS)

Choi, Young-Ung; Park, Miae; Lee, Kyun-Woo; Oh, Chulhong; Park, Heung-Sik

2014-12-01

This study was conducted to investigate the reproductive characteristics of the humbug damselfish, Dascyllus aruanus, through the measurement of gonadosomatic indices (GSI) and histological examination of the gonads. Fish were collected from Chuuk Lagoon, Micronesia (7°27'N; 151°53'E), between August 2009 and July 2010. Overall, the functional sex ratio was approximately 1:1; however, there was a female bias in the smaller size range (35-40 mm standard length [SL]) and male bias in the larger size range (45-60 mm in SL). The process of oocyte development exhibited a group synchronous pattern, from the vitellogenic phase oocytes in the gonads following the two clutches of oocytes, as the primary growth stage and yolk vesicle stage. The testis with an ovarian lumen exists as a central slit, and the sperm ducts extend into the medial hilar region of the gonads, indicating that males of D. aruanus have a secondary testis of protogynous species. Monthly variations in the GSI and evolution of gonad status indicated that reproductive activity in this species occurs throughout the year in Chuuk Lagoon, Micronesia.

Latitudinal variation of leaf stomatal traits from species to community level in forests: linkage with ecosystem productivity

PubMed Central

Wang, Ruili; Yu, Guirui; He, Nianpeng; Wang, Qiufeng; Zhao, Ning; Xu, Zhiwei; Ge, Jianping

2015-01-01

To explore the latitudinal variation of stomatal traits from species to community level and their linkage with net primary productivity (NPP), we investigated leaf stomatal density (SDL) and stomatal length (SLL) across 760 species from nine forest ecosystems in eastern China, and calculated the community-level SD (SDC) and SL (SLC) through species-specific leaf area index (LAI). Our results showed that latitudinal variation in species-level SDL and SLL was minimal, but community-level SDC and SLC decreased clearly with increasing latitude. The relationship between SD and SL was negative across species and different plant functional types (PFTs), but positive at the community level. Furthermore, community-level SDC correlated positively with forest NPP, and explained 51% of the variation in NPP. These findings indicate that the trade-off by regulating SDL and SLL may be an important strategy for plant individuals to adapt to environmental changes, and temperature acts as the main factor influencing community-level stomatal traits through alteration of species composition. Importantly, our findings provide new insight into the relationship between plant traits and ecosystem function. PMID:26403303

Predicting onset and duration of airborne allergenic pollen season in the United States

NASA Astrophysics Data System (ADS)

Zhang, Yong; Bielory, Leonard; Cai, Ting; Mi, Zhongyuan; Georgopoulos, Panos

2015-02-01

Allergenic pollen is one of the main triggers of Allergic Airway Disease (AAD) affecting 5%-30% of the population in industrialized countries. A modeling framework has been developed using correlation and collinearity analyses, simulated annealing, and stepwise regression based on nationwide observations of airborne pollen counts and climatic factors to predict the onsets and durations of allergenic pollen seasons of representative trees, weeds and grass in the contiguous United States. Main factors considered are monthly, seasonal and annual mean temperatures and accumulative precipitations, latitude, elevation, Growing Degree Day (GDD), Frost Free Day (FFD), Start Date (SD) and Season Length (SL) in the previous year. The estimated mean SD and SL for birch (Betula), oak (Quercus), ragweed (Ambrosia), mugwort (Artemisia) and grass (Poaceae) pollen season in 1994-2010 are mostly within 0-6 days of the corresponding observations for the majority of the National Allergy Bureau (NAB) monitoring stations across the contiguous US. The simulated spatially resolved maps for onset and duration of allergenic pollen season in the contiguous US are consistent with the long term observations.

Inhibition of HIV-1 by a peptide ligand of the genomic RNA packaging signal Psi.

PubMed

Dietz, Julia; Koch, Joachim; Kaur, Ajit; Raja, Chinnappan; Stein, Stefan; Grez, Manuel; Pustowka, Anette; Mensch, Sarah; Ferner, Jan; Möller, Lars; Bannert, Norbert; Tampé, Robert; Divita, Gilles; Mély, Yves; Schwalbe, Harald; Dietrich, Ursula

2008-05-01

The interaction of the nucleocapsid NCp7 of the human immunodeficiency virus type 1 (HIV-1) Gag polyprotein with the RNA packaging signal Psi ensures specific encapsidation of the dimeric full length viral genome into nascent virus particles. Being an essential step in the HIV-1 replication cycle, specific genome encapsidation represents a promising target for therapeutic intervention. We previously selected peptides binding to HIV-1 Psi-RNA or stem loops (SL) thereof by phage display. Herein, we describe synthesis of peptide variants of the consensus HWWPWW motif on membrane supports to optimize Psi-RNA binding. The optimized peptide, psi-pepB, was characterized in detail with respect to its conformation and binding properties for the SL3 of the Psi packaging signal by NMR and tryptophan fluorescence quenching. Functional analysis revealed that psi-pepB caused a strong reduction of virus release by infected cells as monitored by reduced transduction efficiencies, capsid p24 antigen levels, and electron microscopy. Thus, this peptide shows antiviral activity and could serve as a lead compound to develop new drugs targeting HIV-1.

Direct-drive DT implosions with Knudsen number variations

DOE PAGES

Kim, Yong Ho; Herrmann, Hans W.; Hoffman, Nelson M.; ...

2016-05-26

Direct-drive implosions of DT-filled plastic-shells have been conducted at the Omega laser facility, measuring nuclear yields while varying Knudsen numbers (i.e., the ratio of mean free path of fusing ions to the length of fuel region) by adjusting both shell thickness (e.g., 7.5, 15, 20, 30 μm) and fill pressure (e.g., 2, 5, 15 atm). In addition, the fusion reactivity reduction model showed a stronger effect on yield as the Knudsen number increases (or the shell thickness decreases). The Reduced-Ion-Kinetic (RIK) simulation which includes both fusion reactivity reduction and mix model was necessary to provide a better match between themore » observed neutron yields and those simulated.« less

Making Sense of the Yeast Sphingolipid Pathway.

PubMed

Megyeri, Márton; Riezman, Howard; Schuldiner, Maya; Futerman, Anthony H

2016-12-04

Sphingolipids (SL) and their metabolites play key roles both as structural components of membranes and as signaling molecules. Many of the key enzymes and regulators of SL metabolism were discovered using the yeast Saccharomyces cerevisiae, and based on the high degree of conservation, a number of mammalian homologs were identified. Although yeast continues to be an important tool for SL research, the complexity of SL structure and nomenclature often hampers the ability of new researchers to grasp the subtleties of yeast SL biology and discover new modulators of this intricate pathway. Moreover, the emergence of lipidomics by mass spectrometry has enabled the rapid identification of SL species in yeast and rendered the analysis of SL composition under various physiological and pathophysiological conditions readily amenable. However, the complex nomenclature of the identified species renders much of the data inaccessible to non-specialists. In this review, we focus on parsing both the classical SL nomenclature and the nomenclature normally used during mass spectrometry analysis, which should facilitate the understanding of yeast SL data and might shed light on biological processes in which SLs are involved. Finally, we discuss a number of putative roles of various yeast SL species. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ethanolic extract of seabuckthorn (Hippophae rhamnoides L) prevents high-fat diet-induced obesity in mice through down-regulation of adipogenic and lipogenic gene expression.

PubMed

Pichiah, P B Tirupathi; Moon, Hye-Jung; Park, Jeong-Eun; Moon, Yeon-Jeong; Cha, Youn-Soo

2012-11-01

Phenolic compounds and flavonoids ameliorate bodyweight, blood glucose, and serum lipid profile. Since seabuckthorn (Hippophae rhamnoides L.) is known as a rich source of isoflavones and flavonoids, we hypothesized that ethanolic extract of seabuckthorn leaves (SL) may have anti-obesity and hypoglycemic effects. To investigate the effect of ethanolic extract of SL, 32 C57BL/6J mice were randomly divided into 4 dietary groups, containing 8 mice in each group: normal diet group; high-fat diet (HD) control group; high-fat diet with SL extract, 500 mg/kg body weight (BW) (SL1) group; and high-fat diet with SL extract, 1000 mg/kg BW (SL2) group. After 13 weeks, it was observed that oral administration of SL extract significantly reduced the energy intake; BW gain; epididymal fat pad weight; hepatic triglyceride, hepatic, and serum total cholesterol levels; and serum leptin levels in the SL groups compared to the HD group. However, differences in serum triglyceride and insulin levels in the SL groups were not significant in comparison to the HD group. The hepatic mRNA expression of peroxisome proliferator-activated receptor (PPAR) α and carnitine palmitoyltransferase 1 along with PPAR-γ were significantly increased in SL groups, whereas the level of acetyl-CoA carboxylase was significantly reduced in SL groups compared to HD group. Our results indicated that SL is effective in preventing BW gain and fat accumulation in the liver; it also reduced adipose tissue mass, hepatic lipid profile, and serum leptin level in the mouse. Together, these observations suggest that SL is a potential agent to study in the management of obesity and related disorders. Copyright © 2012 Elsevier Inc. All rights reserved.

Enhancing Tropane Alkaloid Production Based on the Functional Identification of Tropine-Forming Reductase in Scopolia lurida, a Tibetan Medicinal Plant.

PubMed

Zhao, Kaihui; Zeng, Junlan; Zhao, Tengfei; Zhang, Haoxing; Qiu, Fei; Yang, Chunxian; Zeng, Lingjiang; Liu, Xiaoqiang; Chen, Min; Lan, Xiaozhong; Liao, Zhihua

2017-01-01

Scopolia lurida , a native herbal plant species in Tibet, is one of the most effective producers of tropane alkaloids. However, the tropane alkaloid biosynthesis in this plant species of interest has yet to be studied at the molecular, biochemical, and biotechnological level. Here, we report on the isolation and characterization of a putative short chain dehydrogenase (SDR) gene. Sequence analysis showed that SlTRI belonged to the SDR family. Phylogenetic analysis revealed that SlTRI was clustered with the tropine-forming reductases. SlTRI and the other TA-biosynthesis genes, including putrescine N-methyltransferase ( SlPMT ) and hyoscyamine 6 β -hydroxylase ( SlH6H ), were preferably or exclusively expressed in the S . lurida roots. The tissue profile of SlTRI suggested that this gene might be involved in tropane alkaloid biosynthesis. By using GC-MS, SlTRI was shown to catalyze the tropinone reduction to yield tropine, the key intermediate of tropane alkaloids. With the purified recombinant SlTRI from Escherichia coli , an enzymatic assay was carried out; its result indicated that SlTRI was a tropine-forming reductase. Finally, the role of SlTRI in promoting the tropane alkaloid biosynthesis was confirmed through metabolic engineering in S . lurida . Specifically, hairy root cultures of S . lurida were established to investigate the effects of SlTRI overexpression on tropane alkaloid accumulation. In the SlTRI -overexpressing root cultures, the hyoscyamine contents were 1.7- to 2.9-fold higher than those in control while their corresponding scopolamine contents were likewise elevated. In summary, this functional identification of SlTRI has provided for a better understanding of tropane alkaloid biosynthesis. It also provides a candidate gene for enhancing tropane alkaloid biosynthesis in S . lurida via metabolic engineering.

Enhancing Tropane Alkaloid Production Based on the Functional Identification of Tropine-Forming Reductase in Scopolia lurida, a Tibetan Medicinal Plant

PubMed Central

Zhao, Kaihui; Zeng, Junlan; Zhao, Tengfei; Zhang, Haoxing; Qiu, Fei; Yang, Chunxian; Zeng, Lingjiang; Liu, Xiaoqiang; Chen, Min; Lan, Xiaozhong; Liao, Zhihua

2017-01-01

Scopolia lurida, a native herbal plant species in Tibet, is one of the most effective producers of tropane alkaloids. However, the tropane alkaloid biosynthesis in this plant species of interest has yet to be studied at the molecular, biochemical, and biotechnological level. Here, we report on the isolation and characterization of a putative short chain dehydrogenase (SDR) gene. Sequence analysis showed that SlTRI belonged to the SDR family. Phylogenetic analysis revealed that SlTRI was clustered with the tropine-forming reductases. SlTRI and the other TA-biosynthesis genes, including putrescine N-methyltransferase (SlPMT) and hyoscyamine 6β-hydroxylase (SlH6H), were preferably or exclusively expressed in the S. lurida roots. The tissue profile of SlTRI suggested that this gene might be involved in tropane alkaloid biosynthesis. By using GC-MS, SlTRI was shown to catalyze the tropinone reduction to yield tropine, the key intermediate of tropane alkaloids. With the purified recombinant SlTRI from Escherichia coli, an enzymatic assay was carried out; its result indicated that SlTRI was a tropine-forming reductase. Finally, the role of SlTRI in promoting the tropane alkaloid biosynthesis was confirmed through metabolic engineering in S. lurida. Specifically, hairy root cultures of S. lurida were established to investigate the effects of SlTRI overexpression on tropane alkaloid accumulation. In the SlTRI-overexpressing root cultures, the hyoscyamine contents were 1.7- to 2.9-fold higher than those in control while their corresponding scopolamine contents were likewise elevated. In summary, this functional identification of SlTRI has provided for a better understanding of tropane alkaloid biosynthesis. It also provides a candidate gene for enhancing tropane alkaloid biosynthesis in S. lurida via metabolic engineering. PMID:29085381

Two tomato GDP-D-mannose epimerase isoforms involved in ascorbate biosynthesis play specific roles in cell wall biosynthesis and development.

PubMed

Mounet-Gilbert, Louise; Dumont, Marie; Ferrand, Carine; Bournonville, Céline; Monier, Antoine; Jorly, Joana; Lemaire-Chamley, Martine; Mori, Kentaro; Atienza, Isabelle; Hernould, Michel; Stevens, Rebecca; Lehner, Arnaud; Mollet, Jean Claude; Rothan, Christophe; Lerouge, Patrice; Baldet, Pierre

2016-08-01

GDP-D-mannose epimerase (GME, EC 5.1.3.18) converts GDP-D-mannose to GDP-L-galactose, and is considered to be a central enzyme connecting the major ascorbate biosynthesis pathway to primary cell wall metabolism in higher plants. Our previous work demonstrated that GME is crucial for both ascorbate and cell wall biosynthesis in tomato. The aim of the present study was to investigate the respective role in ascorbate and cell wall biosynthesis of the two SlGME genes present in tomato by targeting each of them through an RNAi-silencing approach. Taken individually SlGME1 and SlGME2 allowed normal ascorbate accumulation in the leaf and fruits, thus suggesting the same function regarding ascorbate. However, SlGME1 and SlGME2 were shown to play distinct roles in cell wall biosynthesis, depending on the tissue considered. The RNAi-SlGME1 plants harbored small and poorly seeded fruits resulting from alterations of pollen development and of pollination process. In contrast, the RNAi-SlGME2 plants exhibited vegetative growth delay while fruits remained unaffected. Analysis of SlGME1- and SlGME2-silenced seeds and seedlings further showed that the dimerization state of pectin rhamnogalacturonan-II (RG-II) was altered only in the RNAi-SlGME2 lines. Taken together with the preferential expression of each SlGME gene in different tomato tissues, these results suggest sub-functionalization of SlGME1 and SlGME2 and their specialization for cell wall biosynthesis in specific tomato tissues. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Ectopic Overexpression of SlHsfA3, a Heat Stress Transcription Factor from Tomato, Confers Increased Thermotolerance and Salt Hypersensitivity in Germination in Transgenic Arabidopsis

PubMed Central

Li, Zhenjun; Zhang, Lili; Wang, Aoxue; Xu, Xiangyang; Li, Jingfu

2013-01-01

Plant heat stress transcription factors (Hsfs) are the critical components involved in mediating responses to various environmental stressors. However, the detailed roles of many plant Hsfs are far from fully understood. In this study, an Hsf (SlHsfA3) was isolated from the cultivated tomato (Solanum lycopersicum, Sl) and functionally characterized at the genetic and developmental levels. The nucleus-localized SlHsfA3 was basally and ubiquitously expressed in different plant organs. The expression of SlHsfA3 was induced dramatically by heat stress, moderately by high salinity, and slightly by drought, but was not induced by abscisic acid (ABA). The ectopic overexpression of SlHsfA3 conferred increased thermotolerance and late flowering phenotype to transgenic Arabidopsis plants. Moreover, SlHsfA3 played a negative role in controlling seed germination under salt stress. RNA-sequencing data demonstrated that a number of heat shock proteins (Hsps) and stress-associated genes were induced in Arabidopsis plants overexpressing SlHsfA3. A gel shift experiment and transient expression assays in Nicotiana benthamiana leaves demonstrated that SlHsfA3 directly activates the expression of SlHsp26.1-P and SlHsp21.5-ER. Taken together, our results suggest that SlHsfA3 behaves as a typical Hsf to contribute to plant thermotolerance. The late flowering and seed germination phenotypes and the RNA-seq data derived from SlHsfA3 overexpression lines lend more credence to the hypothesis that plant Hsfs participate in diverse physiological and biochemical processes related to adverse conditions. PMID:23349984

Structure and dynamics of the hydration shells of the Al3+ ion

NASA Astrophysics Data System (ADS)

Bylaska, Eric J.; Valiev, Marat; Rustad, James R.; Weare, John H.

2007-03-01

First principles simulations of the hydration shells surrounding Al3+ ions are reported for temperatures near 300°C. The predicted six water molecules in the octahedral first hydration shell were found to be trigonally coordinated via hydrogen bonds to 12s shell water molecules in agreement with the putative structure used to analyze the x-ray data, but in disagreement with the results reported from conventional molecular dynamics using two-and three-body potentials. Bond lengths and angles of the water molecules in the first and second hydration shells and the average radii of these shells also agreed very well with the results of the x-ray analysis. Water transfers into and out of the second solvation shell were observed to occur on a picosecond time scale via a dissociative mechanism. Beyond the second shell the bonding pattern substantially returned to the tetrahedral structure of bulk water. Most of the simulations were done with 64 solvating water molecules (20ps). Limited simulations with 128 water molecules (7ps) were also carried out. Results agreed as to the general structure of the solvation region and were essentially the same for the first and second shell. However, there were differences in hydrogen bonding and Al-O radial distribution function in the region just beyond the second shell. At the end of the second shell a nearly zero minimum in the Al-O radial distribution was found for the 128 water system. This minimum is less pronounced minimum found for the 64 water system, which may indicate that sizes larger than 64 may be required to reliably predict behavior in this region.

Weak and Saturable Protein–Surfactant Interactions in the Denaturation of Apo-α-Lactalbumin by Acidic and Lactonic Sophorolipid

PubMed Central

Andersen, Kell K.; Vad, Brian S.; Roelants, Sophie; van Bogaert, Inge N. A.; Otzen, Daniel E.

2016-01-01

Biosurfactants are of growing interest as sustainable alternatives to fossil-fuel-derived chemical surfactants, particularly for the detergent industry. To realize this potential, it is necessary to understand how they affect proteins which they may encounter in their applications. However, knowledge of such interactions is limited. Here, we present a study of the interactions between the model protein apo-α-lactalbumin (apo-aLA) and the biosurfactant sophorolipid (SL) produced by the yeast Starmerella bombicola. SL occurs both as an acidic and a lactonic form; the lactonic form (lactSL) is sparingly soluble and has a lower critical micelle concentration (cmc) than the acidic form [non-acetylated acidic sophorolipid (acidSL)]. We show that acidSL affects apo-aLA in a similar way to the related glycolipid biosurfactant rhamnolipid (RL), with the important difference that RL is also active below the cmc in contrast to acidSL. Using isothermal titration calorimetry data, we show that acidSL has weak and saturable interactions with apo-aLA at low concentrations; due to the relatively low cmc of acidSL (which means that the monomer concentration is limited to ca. 0–1 mM SL), it is only possible to observe interactions with monomeric acidSL at high apo-aLA concentrations. However, the denaturation kinetics of apo-aLA in the presence of acidSL are consistent with a collaboration between monomeric and micellar surfactant species, similar to RL and non-ionic or zwitterionic surfactants. Inclusion of diacetylated lactonic sophorolipid (lactSL) as mixed micelles with acidSL lowers the cmc and this effectively reduces the rate of unfolding, emphasizing that SL like other biosurfactants is a gentle anionic surfactant. Our data highlight the potential of these biosurfactants for future use in the detergent and pharmaceutical industry. PMID:27877155

SL4, a chalcone-based compound, induces apoptosis in human cancer cells by activation of the ROS/MAPK signalling pathway.

PubMed

Wang, L-H; Li, H-H; Li, M; Wang, S; Jiang, X-R; Li, Y; Ping, G-F; Cao, Q; Liu, X; Fang, W-H; Chen, G-L; Yang, J-Y; Wu, C-F

2015-12-01

SL4, a chalcone-based compound, exhibits clearly inhibitory effects on HIF-1 and has been shown to effectively suppress tumour invasion and angiogenesis in vitro and in vivo. Here, studies were conducted to determine SL4's anti-apoptotic effects and its underlying mechanisms, in human cancer cells. Cytotoxicity, apoptotic induction and its involved mechanisms of SL4 were investigated using normal cells, cancer cells and mouse xenograft models. The role of reactive oxygen species (ROS) and mitogen-activated protein kinase (MAPK) signalling in SL4-induced apoptosis was explored by manipulating specific scavenger or signalling inhibitors, in cultured cells. SL4 significantly inhibited cell population growth of human cancer cell lines but exhibited lower cytotoxicity against normal cells. In addition, SL4 effectively induced apoptosis of Hep3B and MDA-MB-435 cells by activating procaspase-8, -9 and -3, and down-regulating expression levels of XIAP, but did not affect HIF-1 apoptosis-related targets, Survivin and Bcl-XL. Further study showed that SL4 also reduced mitochondrial membrane potential and promoted generation of ROS. ROS generation and apoptotic induction by SL4 were blocked by NAC, a scavenger of ROS, suggesting SL4-induced apoptosis via ROS accumulation. We also found that MAPKs, JNK and p38, but not ERK1/2, to be critical mediators in SL4-induced apoptosis. SP600125 and SB203580, specific inhibitors of JNK kinase and p38 kinase, significantly retarded apoptosis induced by SL4. Moreover, anti-oxidant NAC blocked activation of JNK and p38 induced by SL4, indicating that ROS may act as upstream signalling of JNK and p38 activation. It is noteworthy that animal studies revealed dramatic reduction (49%) in tumour volume after 11 days SL4 treatment. These data demonstrate that SL4 induced apoptosis in human cancer cells through activation of the ROS/MAPK signalling pathway, suggesting that it may be a novel lead compound, as a cancer drug candidate, with polypharmacological characteristics. © 2015 John Wiley & Sons Ltd.

Patent ductus arteriosus ligation in premature infants in the United States.

PubMed

Tashiro, Jun; Wang, Bo; Sola, Juan E; Hogan, Anthony R; Neville, Holly L; Perez, Eduardo A

2014-08-01

Patent ductus arteriosus (PDA) is a condition that commonly affects premature and low birth weight (BW) infants at times necessitating surgical intervention. We examined outcomes after surgical ligation (SL). We analyzed the Kids' Inpatient Database for premature infants diagnosed with PDA, admitted at <8 d of age. Patient demographics, disposition, morbidity, and mortality were analyzed. All cases were weighted appropriately to project nationally representative estimates. A total of 63,208 patients were identified with diagnosis of PDA. Of these, 6766 (10.7%) underwent SL. Lower gestational age (GA) and BW patients had higher incidence of PDA and rates of SL. Overall survival was 90.8% for the cohort. Survival for the SL group was 88.0% and 91.2% for the non-SL group; however, infants undergoing SL had higher survival rates up to 28 wk and 1250 g for GA and BW, respectively. GA did not affect post-SL survival adversely. Rather, lower BW was associated with extremely high mortality rates. Black infants and boys had lower survival compared with other races and girls, respectively. Larger hospitals had higher survival rates, but hospital location, teaching status, and type did not affect survival. Payer status and income quartile did not affect survival. PDA and SL are more common in lower BW and GA groups. Higher survival rates are found for infants with SL versus non-SL in the lowest BW and GA groups. Morbidity and mortality are not affected by SL timing. BW, rather than GA, determines survival of infants undergoing SL. Copyright © 2014 Elsevier Inc. All rights reserved.

Mutational analysis of three predicted 5'-proximal stem-loop structures in the genome of tick-borne encephalitis virus indicates different roles in RNA replication and translation

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

Rouha, Harald; Hoenninger, Verena M.; Thurner, Caroline

2011-08-15

Flavivirus gene expression is modulated by RNA secondary structure elements at the terminal ends of the viral RNA molecule. For tick-borne encephalitis virus (TBEV), four stem-loop (SL) elements have been predicted in the first 180 nucleotides of the viral genome: 5'-SL1, 5'-SL2, 5'-SL3 and 5'-SL4. The last three of these appear to be unique to tick-borne flaviviruses. Here, we report their characterization by mutagenesis in a TBEV luciferase reporter system. By manipulating their thermodynamic properties, we found that an optimal stability of the 5'-SL2 is required for efficient RNA replication. 5'-SL3 formation is also important for viral RNA replication, butmore » although it contains the viral start codon, its formation is dispensable for RNA translation. 5'-SL4 appears to facilitate both RNA translation and replication. Our data suggest that maintenance of the balanced thermodynamic stability of these SL elements is important for temporal regulation of its different functions.« less

Determining the appropriate sleeve lobectomy versus pneumonectomy ratio in central non-small cell lung cancer patients: an audit of an aggressive policy of pneumonectomy avoidance.

PubMed

Gómez-Caro, Abel; Garcia, Samuel; Reguart, Noemí; Cladellas, Esther; Arguis, Pedro; Sanchez, Marcelo; Gimferrer, Josep Maria

2011-03-01

To study the outcomes of broncho ± angioplastic sleeve lobectomy (SL) versus pneumonectomy (PN), and the PN:SL ratio after an aggressive policy of parenchyma-sparing surgery to improve postoperative complications rate and long-term quality of life (QoL). A prospective study was conducted in 490 patients with non-small cell lung cancer between 2005 and 2009. All patients not suitable for standard lobectomy were scheduled for SL, if possible, or for PN; eight patients with functional impairment were directly scheduled for SL. Of 76 procedures, 21 (4%) were PN and 55 (11%) SL (29 bronchoplastic, seven bronchovascular, seven angioplastic; 11 extended to more than one lobe). There were no surgical, oncological or physiological preoperative differences between the groups. The 5-year PN:SL ratio was 1:2.6 (2005: 1:2.1; 2006: 1:2.6; 2007: 1:3.6; 2008: 1:3; 2009: 1:3.5). SL and PN mortality were 2 (3.6%) and 1 (5%), respectively. Postoperative complications occurred in 18 (32%) SL and 7 (33%) PN patients. pN1 (p = 0.04), vascular reconstruction and upper-left SL were risk factors for postoperative complications of SL (p = 0.03) but were not detected as a mortality risk. Overall 5-year survival was 61% for SL and 31% for PN. Survival at 5 years was significantly higher for SL (p = 0.03, Kaplan-Meier). Age <70 years and SL were positive factors for long-term survival. In multivariate modelling, both remained positive factors. Surviving PN patients experienced significantly greater loss of respiratory function and lower QoL than those who avoided this surgery (preoperative score, PN vs SL: 52 vs 51; 3 months, 41 vs 43; and 6 months, 42 vs 51, p = 0.04). The adjuvant treatment complement was higher in SL at 34 (62%) than at PN 10 (47%). The side effects of this treatment were more frequent in patients with more extirpated parenchyma (p = 0.04). Parenchyma-sparing procedures can reduce the PN rate to less than 10%. A PN:SL index lower than 1:1.5 as a quality standard in a specialised thoracic unit should encourage the use of broncho-angioplastic procedures and improve patient outcomes. Long-term survival, QoL, postoperative lung function test and tolerance of adjuvant therapies are significantly better after SL than PN intervention. Copyright © 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Effect of Different Training Methods on Stride Parameters in Speed Maintenance Phase of 100-m Sprint Running.

PubMed

Cetin, Emel; Hindistan, I Ethem; Ozkaya, Y Gul

2018-05-01

Cetin, E, Hindistan, IE, Ozkaya, YG. Effect of different training methods on stride parameters in speed maintenance phase of 100-m sprint running. J Strength Cond Res 32(5): 1263-1272, 2018-This study examined the effects of 2 different training methods relevant to sloping surface on stride parameters in speed maintenance phase of 100-m sprint running. Twenty recreationally active students were assigned into one of 3 groups: combined training (Com), horizontal training (H), and control (C) group. Com group performed uphill and downhill training on a sloping surface with an angle of 4°, whereas H group trained on a horizontal surface, 3 days a week for 8 weeks. Speed maintenance and deceleration phases were divided into distances with 10-m intervals, and running time (t), running velocity (RV), step frequency (SF), and step length (SL) were measured at preexercise, and postexercise period. After 8 weeks of training program, t was shortened by 3.97% in Com group, and 2.37% in H group. Running velocity also increased for totally 100 m of running distance by 4.13 and 2.35% in Com, and H groups, respectively. At the speed maintenance phase, although t and maximal RV (RVmax) found to be statistically unaltered during overall phase, t was found to be decreased, and RVmax was preceded by 10 m in distance in both training groups. Step length was increased at 60-70 m, and SF was decreased at 70-80 m in H group. Step length was increased with concomitant decrease in SF at 80-90 m in Com group. Both training groups maintained the RVmax with a great percentage at the speed maintenance phase. In conclusion, although both training methods resulted in an increase in running time and RV, Com training method was more prominently effective method in improving RV, and this improvement was originated from the positive changes in SL during the speed maintaining phase.

Identification of differentially regulated maize proteins conditioning Sugarcane mosaic virus systemic infection.

PubMed

Chen, Hui; Cao, Yanyong; Li, Yiqing; Xia, Zihao; Xie, Jipeng; Carr, John P; Wu, Boming; Fan, Zaifeng; Zhou, Tao

2017-08-01

Sugarcane mosaic virus (SCMV) is the most important cause of maize dwarf mosaic disease. To identify maize genes responsive to SCMV infection and that may be involved in pathogenesis, a comparative proteomic analysis was performed using the first and second systemically infected leaves (termed 1 SL and 2 SL, respectively). Seventy-one differentially expressed proteins were identified in 1 SL and 2 SL upon SCMV infection. Among them, eight proteins showed the same changing patterns in both 1 SL and 2 SL. Functional annotations of regulated proteins and measurement of photosynthetic activity revealed that photosynthesis was more inhibited and defensive gene expression more pronounced in 1 SL than in 2 SL. Knockdown of regulated proteins in both 1 SL and 2 SL by a brome mosaic virus-based gene silencing vector in maize indicated that protein disulfide isomerase-like and phosphoglycerate kinase were required for optimal SCMV replication. By contrast, knockdown of polyamine oxidase (ZmPAO) significantly increased SCMV accumulation, implying that ZmPAO activity might contribute to resistance or tolerance. The results suggest that combining comparative proteomic analyses of different tissues and virus-induced gene silencing is an efficient way to identify host proteins supporting virus replication or enhancing resistance to virus infection. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Spin-locking vs. chemical exchange saturation transfer MRI for investigating chemical exchange process between water and labile metabolite protons

PubMed Central

Jin, Tao; Autio, Joonas; Obata, Takayuki; Kim, Seong-Gi

2010-01-01

Chemical exchange saturation transfer (CEST) and spin-locking (SL) experiments were both able to probe the exchange process between protons of non-equivalent chemical environments. To compare the characteristics of the CEST and SL approaches in the study of chemical exchange effects, we performed CEST and SL experiments at varied pH and concentrated metabolites with exchangeable amide, amine, and hydroxyl protons at 9.4 T. Our results show that: i) On-resonance SL is most sensitive to chemical exchanges in the intermediate exchange regime and is able to detect hydroxyl and amine protons on a millimolar concentration scale. Off-resonance SL and CEST approaches are sensitive to slow-exchanging protons when an optimal SL or saturation pulse power matches the exchanging rate, respectively. ii) Offset frequency-dependent SL and CEST spectra are very similar, and can be explained well with an SL model recently developed by Trott and Palmer. iii) The exchange rate and population of metabolite protons can be determined from offset-dependent SL or CEST spectra or from on-resonance SL relaxation dispersion measurements. iv) The asymmetry of the magnetization transfer ratio (MTRasym) is highly dependent on the choice of saturation pulse power. In the intermediate exchange regime, MTRasym becomes complicated and should be interpreted with care. PMID:21500270

Chilling and cooking rate effects on some myofibrillar determinants of tenderness of beef.

PubMed

King, D A; Dikeman, M E; Wheeler, T L; Kastner, C L; Koohmaraie, M

2003-06-01

Our objectives were to examine the effects of prerigor excision and rapid chilling vs. conventional carcass chilling of two muscles on proteolysis and tenderness during the postmortem storage, as well as the effects of fast and slow rates of cooking on myofibrillar characteristics and tenderness. The longissimus thoracis (LT) and triceps brachii (TB), long head muscles were removed 45 min after exsanguination from the left side of 12 carcasses and chilled in an ice bath to induce cold shortening (excised, rapidly chilled). At 24 h postmortem, the corresponding muscles were removed from the right side (conventionally chilled). All muscles were cut into 2.54-cm-thick steaks and assigned to one of two postmortem times (1 or 14 d), and to raw and cooking treatments. Steaks were cooked at 260 degrees C (FAST) or 93 degrees C (SLOW) in a forced-air convection oven to an internal temperature of 70 degrees C. Cooking loss, cooking time, and Warner-Bratzler shear force (WBSF) were measured on cooked steaks. Sarcomere length (SL) and the extent of proteolysis of desmin were measured on raw and cooked steaks. As expected, the excised, rapidly chilled muscles had a much more rapid (P < 0.05) temperature decline than those that were conventionally chilled. The excised, rapidly chilled treatment resulted in shorter (P < 0.05) SL, and SL was shorter (P < 0.05) in LT than in TB steaks. Raw steaks had longer (P < 0.05) SL than cooked steaks, regardless of chilling treatment. The FAST cooking resulted in shorter (P < 0.05) SL than SLOW cooking in conventionally chilled steaks, but cooking rate had no effect (P > 0.05) on SL of rapidly chilled steaks. Generally, TB steaks required longer (P < 0.05) cooking times and had higher (P < 0.05) cooking losses than LT steaks, and FAST-cooked steaks had greater (P < 0.05) cooking losses than SLOW-cooked steaks. Rapidly chilled steaks had less (P < 0.05) degradation of desmin than conventionally chilled steaks (31 vs. 41%). Aging for 14 d increased (P < 0.05) desmin degradation. Rapid chilling of muscles resulted in much higher (P < 0.05) WBSF values, whereas aging resulted in lower (P < 0.05) WBSF values. The SLOW-cooked TB steaks were more tender (P < 0.05) than FAST-cooked TB steaks and LT steaks cooked at either rate. Excised, rapidly chilled muscles underwent proteolysis, but it occurred at a slower rate during the first 24 h postmortem than it did in conventionally chilled muscles. Cooking rate did not affect tenderness of LT steaks, but SLOW cooking resulted in more tender TB steaks.

Estimates of Heritability for Growth and Shell Color Traits and Their Genetic Correlations in the Black Shell Strain of Pacific Oyster Crassostrea gigas.

PubMed

Xu, Lan; Li, Qi; Yu, Hong; Kong, Lingfeng

2017-10-01

The Pacific oyster Crassostrea gigas has been introduced widely and massively and became an economically important aquaculture species on a global scale. We estimated heritabilities of growth and shell color traits and their genetic correlations in black shell strain of C. gigas. Analyses were performed on 22 full-sib families in a nested mating design including 410 individuals at harvest (24 months of age). The parentage assignment was inferred based on four panels of multiplex PCR markers including 10 microsatellite loci and 94.9% of the offspring were unambiguously assigned to single parent pairs. The Spearman correlation test (r = - 0.992, P < 0.001) demonstrated the high consistency of the shell pigmentation (SP) and L* and their same efficacy in shell color measurements. The narrow-sense heritability estimated under the animal model analysis was 0.18 ± 0.12 for shell height, 0.25 ± 0.16 for shell length, 0.10 ± 0.09 for shell width, 0.42 ± 0.20 for total weight, 0.32 ± 0.18 for shell weight, and 0.68 ± 0.16 for L*, 0.69 ± 0.16 for shell pigmentation, respectively. The considerable additive genetic variation in growth and shell color traits will make it feasible to produce genetic improvements for these traits in selective breeding program. High genetic and phenotypic correlations were found among growth traits and among shell color traits. To optimize a selection strategy for both fast growth and pure dark shell strain of C. gigas, it is proposed to take both total weight and black shell as joint objective traits in selective breeding program. Our study offers an important reference in the process of selective breeding in black shell color stain of C. gigas and will facilitate to develop favorable breeding strategies of genetic improvements for this economically important strain.

Reaction growth of MF2/a-C (M = Ca, Mg) core/shell nanowires at the interface of vapor and solid reactants.

PubMed

Huang, Chih-Hao; Chang, Yu-Hsu; Lee, Chi-Young; Chiu, Hsin-Tien

2006-01-03

C(6)F(6) vapor is employed to react with CaC(2) and Mg(3)N(2) to grow CaF(2)/a-C and Mg(2)F(2)/a-C core/shell nanowires (tens of micrometers in length, tens to hundreds of nanometers in wire diameter, and tens of nanometers in core diameter), respectively, in high yields. The growth mechanism is proposed to proceed via a reaction at the interface of the vapor and solid reactants.

Cell Death Control by Matrix Metalloproteinases1[OPEN

PubMed Central

Zimmermann, Dirk; Sieferer, Elke; Pfannstiel, Jens

2016-01-01

In contrast to mammalian matrix metalloproteinases (MMPs) that play important roles in the remodeling of the extracellular matrix in animals, the proteases responsible for dynamic modifications of the plant cell wall are largely unknown. A possible involvement of MMPs was addressed by cloning and functional characterization of Sl2-MMP and Sl3-MMP from tomato (Solanum lycopersicum). The two tomato MMPs were found to resemble mammalian homologs with respect to gelatinolytic activity, substrate preference for hydrophobic amino acids on both sides of the scissile bond, and catalytic properties. In transgenic tomato seedlings silenced for Sl2/3-MMP expression, necrotic lesions were observed at the base of the hypocotyl. Cell death initiated in the epidermis and proceeded to include outer cortical cell layers. In later developmental stages, necrosis spread, covering the entire stem and extending into the leaves of MMP-silenced plants. The subtilisin-like protease P69B was identified as a substrate of Sl2- and Sl3-MMP. P69B was shown to colocalize with Sl-MMPs in the apoplast of the tomato hypocotyl, it exhibited increased stability in transgenic plants silenced for Sl-MMP activity, and it was cleaved and inactivated by Sl-MMPs in vitro. The induction of cell death in Sl2/3-MMP-silenced plants depended on P69B, indicating that Sl2- and Sl3-MMP act upstream of P69B in an extracellular proteolytic cascade that contributes to the regulation of cell death in tomato. PMID:27208293

Changes in Running Mechanics During a 6-Hour Running Race.

PubMed

Giovanelli, Nicola; Taboga, Paolo; Lazzer, Stefano

2017-05-01

To investigate changes in running mechanics during a 6-h running race. Twelve ultraendurance runners (age 41.9 ± 5.8 y, body mass 68.3 ± 12.6 kg, height 1.72 ± 0.09 m) were asked to run as many 874-m flat loops as possible in 6 h. Running speed, contact time (t c ), and aerial time (t a ) were measured in the first lap and every 30 ± 2 min during the race. Peak vertical ground-reaction force (F max ), stride length (SL), vertical downward displacement of the center of mass (Δz), leg-length change (ΔL), vertical stiffness (k vert ), and leg stiffness (k leg ) were then estimated. Mean distance covered by the athletes during the race was 62.9 ± 7.9 km. Compared with the 1st lap, running speed decreased significantly from 4 h 30 min onward (mean -5.6% ± 0.3%, P < .05), while t c increased after 4 h 30 min of running, reaching the maximum difference after 5 h 30 min (+6.1%, P = .015). Conversely, k vert decreased after 4 h, reaching the lowest value after 5 h 30 min (-6.5%, P = .008); t a and F max decreased after 4 h 30 min through to the end of the race (mean -29.2% and -5.1%, respectively, P < .05). Finally, SL decreased significantly (-5.1%, P = .010) during the last hour of the race. Most changes occurred after 4 h continuous self-paced running, suggesting a possible time threshold that could affect performance regardless of absolute running speed.

Critical anisotropies of a geometrically frustrated triangular-lattice antiferromagnet

NASA Astrophysics Data System (ADS)

Swanson, M.; Haraldsen, J. T.; Fishman, R. S.

2009-05-01

This work examines the critical anisotropy required for the local stability of the collinear ground states of a geometrically frustrated triangular-lattice antiferromagnet (TLA). Using a Holstein-Primakoff expansion, we calculate the spin-wave frequencies for the one-, two-, three-, four-, and eight-sublattice (SL) ground states of a TLA with up to third neighbor interactions. Local stability requires that all spin-wave frequencies are real and positive. The two-, four-, and eight-SL phases break up into several regions where the critical anisotropy is a different function of the exchange parameters. We find that the critical anisotropy is a continuous function everywhere except across the two-SL/three-SL and three-SL/four-SL phase boundaries, where the three-SL phase has the higher critical anisotropy.

Use of d-3He proton spectroscopy as a diagnostic of shell rho r in capsule implosion experiments with approximately 0.2 NIF scale high temperature Hohlraums at Omega.

PubMed

Delamater, N D; Wilson, D C; Kyrala, G A; Seifter, A; Hoffman, N M; Dodd, E; Singleton, R; Glebov, V; Stoeckl, C; Li, C K; Petrasso, R; Frenje, J

2008-10-01

We present the calculations and preliminary results from experiments on the Omega laser facility using d-(3)He filled plastic capsule implosions in gold Hohlraums. These experiments aim to develop a technique to measure shell rho r and capsule unablated mass with proton spectroscopy and will be applied to future National Ignition Facility (NIF) experiments with ignition scale capsules. The Omega Hohlraums are 1900 microm length x 1200 microm diameter and have a 70% laser entrance hole. This is approximately a 0.2 NIF scale ignition Hohlraum and reaches temperatures of 265-275 eV similar to those during the peak of the NIF drive. These capsules can be used as a diagnostic of shell rho r, since the d-(3)He gas fill produces 14.7 MeV protons in the implosion, which escape through the shell and produce a proton spectrum that depends on the integrated rho r of the remaining shell mass. The neutron yield, proton yield, and spectra change with capsule shell thickness as the unablated mass or remaining capsule rho r changes. Proton stopping models are used to infer shell unablated mass and shell rho r from the proton spectra measured with different filter thicknesses. The experiment is well modeled with respect to Hohlraum energetics, neutron yields, and x-ray imploded core image size, but there are discrepancies between the observed and simulated proton spectra.

Adaptive shell color plasticity during the early ontogeny of an intertidal keystone snail.

PubMed

Manríquez, Patricio H; Lagos, Nelson A; Jara, María Elisa; Castilla, Juan Carlos

2009-09-22

We report a mechanism of crypsis present during the vulnerable early post-metamorphic ontogeny (95%) of specimens bearing patterns of shell coloration (dark or light colored) that matched the background coloration provided by patches of Concholepas' most abundant prey (mussels or barnacles respectively). The variation in shell color was positively associated with the color of the most common prey (r = 0.99). In laboratory experiments, shell coloration of C. concholepas depended on the prey-substrate used to induce metamorphosis and for the post-metamorphic rearing. The snail shell color matched the color of the prey offered during rearing. Laboratory manipulation experiments, switching the prey during rearing, showed a corresponding change in snail shell color along the outermost shell edge. As individuals grew and became increasingly indistinguishable from the surrounding background, cryptic individuals had higher survival (71%) than the non cryptic ones (4%) when they were reared in the presence of the predatory crab Acanthocyclus hassleri. These results suggest that the evolution of shell color plasticity during the early ontogeny of C. concholepas, depends on the color of the more abundant of the consumed prey available in the natural habitat where settlement has taken place; this in turn has important consequences for their fitness and survivorship in the presence of visual predators.

Adaptive shell color plasticity during the early ontogeny of an intertidal keystone snail

PubMed Central

Manríquez, Patricio H.; Lagos, Nelson A.; Jara, María Elisa; Castilla, Juan Carlos

2009-01-01

We report a mechanism of crypsis present during the vulnerable early post-metamorphic ontogeny (≤20 mm peristomal length) of the muricid snail Concholepas concholepas, a rocky shore keystone predator characteristic of the southeastern Pacific coast. In the field, we found a significant occurrence (>95%) of specimens bearing patterns of shell coloration (dark or light colored) that matched the background coloration provided by patches of Concholepas' most abundant prey (mussels or barnacles respectively). The variation in shell color was positively associated with the color of the most common prey (r = 0.99). In laboratory experiments, shell coloration of C. concholepas depended on the prey-substrate used to induce metamorphosis and for the post-metamorphic rearing. The snail shell color matched the color of the prey offered during rearing. Laboratory manipulation experiments, switching the prey during rearing, showed a corresponding change in snail shell color along the outermost shell edge. As individuals grew and became increasingly indistinguishable from the surrounding background, cryptic individuals had higher survival (71%) than the non cryptic ones (4%) when they were reared in the presence of the predatory crab Acanthocyclus hassleri. These results suggest that the evolution of shell color plasticity during the early ontogeny of C. concholepas, depends on the color of the more abundant of the consumed prey available in the natural habitat where settlement has taken place; this in turn has important consequences for their fitness and survivorship in the presence of visual predators. PMID:19805296

Reduced magnetohydrodynamic theory of oblique plasmoid instabilities

NASA Astrophysics Data System (ADS)

Baalrud, S. D.; Bhattacharjee, A.; Huang, Y.-M.

2012-02-01

The three-dimensional nature of plasmoid instabilities is studied using the reduced magnetohydrodynamic equations. For a Harris equilibrium with guide field, represented by Bo=Bpotanh(x /λ)ŷ+Bzoẑ, a spectrum of modes are unstable at multiple resonant surfaces in the current sheet, rather than just the null surface of the poloidal field Byo(x)=Bpotanh(x /λ), which is the only resonant surface in 2D or in the absence of a guide field. Here, Bpo is the asymptotic value of the equilibrium poloidal field, Bzo is the constant equilibrium guide field, and λ is the current sheet width. Plasmoids on each resonant surface have a unique angle of obliquity θ ≡arctan(kz/ky). The resonant surface location for angle θ is xs=λarctanh(μ), where μ =tanθBzo/Bpo and the existence of a resonant surface requires |θ |

Self selected speed and maximal lactate steady state speed in swimming.

PubMed

Baron, B; Dekerle, J; Depretz, S; Lefevre, T; Pelayo, P

2005-03-01

The purposes of this study were to ascertain whether physiological and stroking parameters remain stable during a 2-hour exercise performed at self-selected swimming speed (S4) and whether this speed corresponds to those associated with the maximal lactate steady state (SMLSS). Ten well-trained competitive swimmers performed a maximal 400-m front crawl test, 4 30-min swimming tests in order to determine S(MLSS) and a 2-hour test swum at their preferred paces to determine self-selected swimming speed (S4), stroke rate (SR4), and stroke length (SL4) defined as the mean values observed between the 5th and the 15th min of this test. The stroking, metabolic and respiratory parameters, and ratings of perceived exertion (CR10) were reported throughout the 2-hour test. S4 and SMLSS were not significantly different and were highly correlated (r=0.891). S4 and SL4 decreased significantly after a steady state of 68 min and 100 min, respectively, whereas SR4 remained constant. Mean VO2, dioxide output, and heart rate values did not evolve significantly between the 10th and 120th minute of the test whereas capillary blood lactate concentration (La) decreased significantly (p<0.05). Moreover, respiratory CR10 did not evolve significantly between the 10th and the 120th minute of the test whereas general CR10 and muscular CR10 increased significantly. Considering the (La), SL4 and CR10 values variations, muscular parameters and a probably glycogenic depletion seem to be the main limiting factors that prevent maintaining the self selected swimming speed.

A new algebraic turbulence model for accurate description of airfoil flows

NASA Astrophysics Data System (ADS)

Xiao, Meng-Juan; She, Zhen-Su

2017-11-01

We report a new algebraic turbulence model (SED-SL) based on the SED theory, a symmetry-based approach to quantifying wall turbulence. The model specifies a multi-layer profile of a stress length (SL) function in both the streamwise and wall-normal directions, which thus define the eddy viscosity in the RANS equation (e.g. a zero-equation model). After a successful simulation of flat plate flow (APS meeting, 2016), we report here further applications of the model to the flow around airfoil, with significant improvement of the prediction accuracy of the lift (CL) and drag (CD) coefficients compared to other popular models (e.g. BL, SA, etc.). Two airfoils, namely RAE2822 airfoil and NACA0012 airfoil, are computed for over 50 cases. The results are compared to experimental data from AGARD report, which shows deviations of CL bounded within 2%, and CD within 2 counts (10-4) for RAE2822 and 6 counts for NACA0012 respectively (under a systematic adjustment of the flow conditions). In all these calculations, only one parameter (proportional to the Karmen constant) shows slight variation with Mach number. The most remarkable outcome is, for the first time, the accurate prediction of the drag coefficient. The other interesting outcome is the physical interpretation of the multi-layer parameters: they specify the corresponding multi-layer structure of turbulent boundary layer; when used together with simulation data, the SED-SL enables one to extract physical information from empirical data, and to understand the variation of the turbulent boundary layer.

Retrograde accretion of a Caribbean fringing reef controlled by hurricanes and sea-level rise

NASA Astrophysics Data System (ADS)

Blanchon, Paul; Richards, Simon; Bernal, Juan Pablo; Cerdeira-Estrada, Sergio; Ibarra, M. Socrates; Corona-Martínez, Liliana; Martell-Dubois, Raúl

2017-10-01

Predicting the impact of sea-level (SL) rise on coral reefs requires reliable models of reef accretion. Most assume that accretion results from vertical growth of coralgal framework, but recent studies show that reefs exposed to hurricanes consist of layers of coral gravel rather than in-place corals. New models are therefore needed to account for hurricane impact on reef accretion over geological timescales. To investigate this geological impact, we report the configuration and development of a 4-km-long fringing reef at Punta Maroma along the northeast Yucatan Peninsula. Satellite-derived bathymetry shows the crest is set-back a uniform distance of 315 ±15 m from a mid-shelf slope break, and the reef-front decreases 50% in width and depth along its length. A 12-core drill transect constrained by multiple 230Th ages shows the reef is composed of an 2-m thick layer of coral clasts that has retrograded 100 m over its back-reef during the last 5.5 ka. These findings are consistent with a hurricane-control model of reef development where large waves trip and break over the mid-shelf slope break, triggering rapid energy dissipation and thus limiting how far upslope individual waves can fragment corals and redistribute clasts. As SL rises and water depth increases, energy dissipation during wave-breaking is reduced, extending the clast-transport limit, thus leading to reef retrogradation. This hurricane model may be applicable to a large sub-set of fringing reefs in the tropical Western-Atlantic necessitating a reappraisal of their accretion rates and response to future SL rise.

Insights into the mechanisms of RNA secondary structure destabilization by the HIV-1 nucleocapsid protein.

PubMed

Belfetmi, Anissa; Zargarian, Loussiné; Tisné, Carine; Sleiman, Dona; Morellet, Nelly; Lescop, Ewen; Maskri, Ouerdia; René, Brigitte; Mély, Yves; Fossé, Philippe; Mauffret, Olivier

2016-04-01

The mature HIV-1 nucleocapsid protein NCp7 (NC) plays a key role in reverse transcription facilitating the two obligatory strand transfers. Several properties contribute to its efficient chaperon activity: preferential binding to single-stranded regions, nucleic acid aggregation, helix destabilization, and rapid dissociation from nucleic acids. However, little is known about the relationships between these different properties, which are complicated by the ability of the protein to recognize particular HIV-1 stem-loops, such as SL1, SL2, and SL3, with high affinity and without destabilizing them. These latter properties are important in the context of genome packaging, during which NC is part of the Gag precursor. We used NMR to investigate destabilization of the full-length TAR (trans activating response element) RNA by NC, which is involved in the first strand transfer step of reverse transcription. NC was used at a low protein:nucleotide (nt) ratio of 1:59 in these experiments. NMR data for the imino protons of TAR identified most of the base pairs destabilized by NC. These base pairs were adjacent to the loops in the upper part of the TAR hairpin rather than randomly distributed. Gel retardation assays showed that conversion from the initial TAR-cTAR complex to the fully annealed form occurred much more slowly at the 1:59 ratio than at the higher ratios classically used. Nevertheless, NC significantly accelerated the formation of the initial complex at a ratio of 1:59. © 2016 Belfetmi et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

Biophysical characterization of a swimmer with a unilateral arm amputation: a case study.

PubMed

Figueiredo, Pedro; Willig, Renata; Alves, Francisco; Vilas-Boas, João Paulo; Fernandes, Ricardo J

2014-11-01

To examine the effect of swimming speed (v) on the biomechanical and physiological responses of a trained front-crawl swimmer with a unilateral arm amputation. A 13-y-old girl with a unilateral arm amputation (level of the elbow) was tested for stroke length (SL, horizontal displacement cover with each stroke cycle), stroke frequency (SF, inverse of the time to complete each stroke cycle), adapted index of coordination (IdCadapt, lag time between propulsive phases), intracycle velocity variation (IVV, coefficient of variation of the instantaneous velocity-time data), active drag (D, hydrodynamic resistance), and energy cost (C, ratio of metabolic power to speed) during trials of increasing v. Swimmer data showed a positive relationship between v and SF (R² = 1, P < .001), IVV (R² = .98, P = .002), D (R² = .98, P < .001), and C (R² = .95, P = .001) and a negative relationship with the SL (R² = .99, P = .001). No relation was found between v and IdCadapt (R² = .35, P = .22). A quadratic regression best fitted the relationship between v and general kinematical parameters (SL and SF); a cubic relationship fit the IVV best. The relationship between v and D was best expressed by a power regression, and the linear regression fit the C and IdCadapt best. The subject's adaptation to increased v was different from able-bodied swimmers, mainly on interarm coordination, maintaining the lag time between propulsive phases, which influence the magnitude of the other parameters. These results might be useful to develop specific training and enhance swimming performance in swimmers with amputations.

Sublingual buprenorphine is effective in the treatment of chronic pain syndrome.

PubMed

Malinoff, Herbert L; Barkin, Robert L; Wilson, Geoffrey

2005-01-01

Many patients with chronic pain have less than optimal therapeutic outcomes after prolonged treatment with opiate analgesics. Worsening of pain perception, functional capacity, and mood often result. Medical detoxification is often undertaken in this situation. Ninety-five consecutive patients (49 men and 46 women; age range, 26-84) with chronic noncancer pain (maldynia) were referred by local pain clinics for detoxification from long-term opiate analgesic (LTOA) therapy. All patients had failed treatment as manifest by increasing pain levels, worsening functional capacity, and, in 8%, the emergence of opiate addiction. Length of prior LTOA therapy ranged from 1.5 to 27 years (mean, 8.8 years). After a minimum of 12 hours of abstinence from all opiate analgesics, patients were given low doses of sublingual (SL) buprenorphine or buprenorphine/naloxone (Reckitt Benckiser). Maintenance dosing was individualized to treat chronic pain. Daily SL dose of buprenorphine ranged from 4 to 16 mg (mean, 8 mg) in divided doses. Mean duration of treatment is 8.8 months (range, 2.4-16.6 months). At clinic appointments, patients were assessed for pain reports, functional capacity, and mood inventory. Eighty-six percent of patients experienced moderate to substantial relief of pain accompanied by both improved mood and functioning. Patient and family satisfaction was robust. Only 6 patients discontinued therapy secondary to side effects and/or exacerbation of pain. In this open-label study, SL buprenorphine and buprenorphine/naloxone were well tolerated and safe and appeared to be effective in the treatment of chronic pain patients refractory to LTOA.

Significant efficiency enhancement of hybrid solar cells using core-shell nanowire geometry for energy harvesting.

PubMed

Tsai, Shin-Hung; Chang, Hung-Chih; Wang, Hsin-Hua; Chen, Szu-Ying; Lin, Chin-An; Chen, Show-An; Chueh, Yu-Lun; He, Jr-Hau

2011-12-27

A novel strategy employing core-shell nanowire arrays (NWAs) consisting of Si/regioregular poly(3-hexylthiophene) (P3HT) was demonstrated to facilitate efficient light harvesting and exciton dissociation/charge collection for hybrid solar cells (HSCs). We experimentally demonstrate broadband and omnidirectional light-harvesting characteristics of core-shell NWA HSCs due to their subwavelength features, further supported by the simulation based on finite-difference time domain analysis. Meanwhile, core-shell geometry of NWA HSCs guarantees efficient charge separation since the thickness of the P3HT shells is comparable to the exciton diffusion length. Consequently, core-shell HSCs exhibit a 61% improvement of short-circuit current for a conversion efficiency (η) enhancement of 31.1% as compared to the P3HT-infiltrated Si NWA HSCs with layers forming a flat air/polymer cell interface. The improvement of crystal quality of P3HT shells due to the formation of ordering structure at Si interfaces after air mass 1.5 global (AM 1.5G) illumination was confirmed by transmission electron microscopy and Raman spectroscopy. The core-shell geometry with the interfacial improvement by AM 1.5G illumination promotes more efficient exciton dissociation and charge separation, leading to η improvement (∼140.6%) due to the considerable increase in V(oc) from 257 to 346 mV, J(sc) from 11.7 to 18.9 mA/cm(2), and FF from 32.2 to 35.2%, which is not observed in conventional P3HT-infiltrated Si NWA HSCs. The stability of the Si/P3HT core-shell NWA HSCs in air ambient was carefully examined. The core-shell geometry should be applicable to many other material systems of solar cells and thus holds high potential in third-generation solar cells.

Reversed field pinch operation with intelligent shell feedback control in EXTRAP T2R

NASA Astrophysics Data System (ADS)

Brunsell, P. R.; Kuldkepp, M.; Menmuir, S.; Cecconello, M.; Hedqvist, A.; Yadikin, D.; Drake, J. R.; Rachlew, E.

2006-11-01

Discharges in the thin shell reversed field pinch (RFP) device EXTRAP T2R without active feedback control are characterized by growth of non-resonant m = 1 unstable resistive wall modes (RWMs) in agreement with linear MHD theory. Resonant m = 1 tearing modes (TMs) exhibit initially fast rotation and the associated perturbed radial fields at the shell are small, but eventually TMs wall-lock and give rise to a growing radial field. The increase in the radial field at the wall due to growing RWMs and wall-locked TMs is correlated with an increase in the toroidal loop voltage, which leads to discharge termination after 3-4 wall times. An active magnetic feedback control system has been installed in EXTRAP T2R. A two-dimensional array of 128 active saddle coils (pair-connected into 64 independent m = 1 coils) is used with intelligent shell feedback control to suppress the m = 1 radial field at the shell. With feedback control, active stabilization of the full toroidal spectrum of 16 unstable m = 1 non-resonant RWMs is achieved, and TM wall locking is avoided. A three-fold extension of the pulse length, up to the power supply limit, is observed. Intelligent shell feedback control is able to maintain the plasma equilibrium for 10 wall times, with plasma confinement parameters sustained at values comparable to those obtained in thick shell devices of similar size.

Extreme ocean acidification reduces the susceptibility of eastern oyster shells to a polydorid parasite.

PubMed

Clements, J C; Bourque, D; McLaughlin, J; Stephenson, M; Comeau, L A

2017-11-01

Ocean acidification poses a threat to marine organisms. While the physiological and behavioural effects of ocean acidification have received much attention, the effects of acidification on the susceptibility of farmed shellfish to parasitic infections are poorly understood. Here we describe the effects of moderate (pH 7.5) and extreme (pH 7.0) ocean acidification on the susceptibility of Crassostrea virginica shells to infection by a parasitic polydorid, Polydora websteri. Under laboratory conditions, shells were exposed to three pH treatments (7.0, 7.5 and 8.0) for 3- and 5-week periods. Treated shells were subsequently transferred to an oyster aquaculture site (which had recently reported an outbreak of P. websteri) for 50 days to test for effects of pH and exposure time on P. websteri recruitment to oyster shells. Results indicated that pH and exposure time did not affect the length, width or weight of the shells. Interestingly, P. websteri counts were significantly lower under extreme (pH 7.0; ~50% reduction), but not moderate (pH 7.5; ~20% reduction) acidification levels; exposure time had no effect. This study suggests that extreme levels - but not current and projected near-future levels - of acidification (∆pH ~1 unit) can reduce the susceptibility of eastern oyster shells to P. websteri infections. © 2017 John Wiley & Sons Ltd.

Continuous and scalable polymer capsule processing for inertial fusion energy target shell fabrication using droplet microfluidics.

PubMed

Li, Jin; Lindley-Start, Jack; Porch, Adrian; Barrow, David

2017-07-24

High specification, polymer capsules, to produce inertial fusion energy targets, were continuously fabricated using surfactant-free, inertial centralisation, and ultrafast polymerisation, in a scalable flow reactor. Laser-driven, inertial confinement fusion depends upon the interaction of high-energy lasers and hydrogen isotopes, contained within small, spherical and concentric target shells, causing a nuclear fusion reaction at ~150 M°C. Potentially, targets will be consumed at ~1 M per day per reactor, demanding a 5000x unit cost reduction to ~$0.20, and is a critical, key challenge. Experimentally, double emulsions were used as templates for capsule-shells, and were formed at 20 Hz, on a fluidic chip. Droplets were centralised in a dynamic flow, and their shapes both evaluated, and mathematically modeled, before subsequent shell solidification. The shells were photo-cured individually, on-the-fly, with precisely-actuated, millisecond-length (70 ms), uniform-intensity UV pulses, delivered through eight, radially orchestrated light-pipes. The near 100% yield rate of uniform shells had a minimum 99.0% concentricity and sphericity, and the solidification processing period was significantly reduced, over conventional batch methods. The data suggest the new possibility of a continuous, on-the-fly, IFE target fabrication process, employing sequential processing operations within a continuous enclosed duct system, which may include cryogenic fuel-filling, and shell curing, to produce ready-to-use IFE targets.

Slicing for Biology.

ERIC Educational Resources Information Center

Ekstrom, James

2001-01-01

Advocates using computer imaging technology to assist students in doing projects in which determining density is important. Students can study quantitative comparisons of masses, lengths, and widths using computer software. Includes figures displaying computer images of shells, yeast cultures, and the Aral Sea. (SAH)

Overexpression of a novel MADS-box gene SlFYFL delays senescence, fruit ripening and abscission in tomato

PubMed Central

Xie, Qiaoli; Hu, Zongli; Zhu, Zhiguo; Dong, Tingting; Zhao, Zhiping; Cui, Baolu; Chen, Guoping

2014-01-01

MADS-domain proteins are important transcription factors involved in many biological processes of plants. In our study, a tomato MADS-box gene, SlFYFL, was isolated. SlFYFL is expressed in all tissues of tomato and significantly higher in mature leave, fruit of different stages, AZ (abscission zone) and sepal. Delayed leaf senescence and fruit ripening, increased storability and longer sepals were observed in 35S:FYFL tomato. The accumulation of carotenoid was reduced, and ethylene content, ethylene biosynthetic and responsive genes were down-regulated in 35S:FYFL fruits. Abscission zone (AZ) did not form normally and abscission zone development related genes were declined in AZs of 35S:FYFL plants. Yeast two-hybrid assay revealed that SlFYFL protein could interact with SlMADS-RIN, SlMADS1 and SlJOINTLESS, respectively. These results suggest that overexpression of SlFYFL regulate fruit ripening and development of AZ via interactions with the ripening and abscission zone-related MADS box proteins. PMID:24621662

How specific is second language-learning ability? A twin study exploring the contributions of first language achievement and intelligence to second language achievement.

PubMed

Rimfeld, K; Dale, P S; Plomin, R

2015-09-22

Learning a second language is crucially important in an increasingly global society, yet surprisingly little is known about why individuals differ so substantially in second language (SL) achievement. We used the twin design to assess the nature, nurture and mediators of individual differences in SL achievement. For 6263 twin pairs, we analyzed scores from age 16 UK-wide standardized tests, the General Certificate of Secondary Education (GCSE). We estimated genetic and environmental influences on the variance of SL for specific languages, the links between SL and English and the extent to which the links between SL and English are explained by intelligence. All SL measures showed substantial heritability, although heritability was nonsignificantly lower for German (36%) than the other languages (53-62%). Multivariate genetic analyses indicated that a third of genetic influence in SL is shared with intelligence, a third with English independent of intelligence and a further third is unique to SL.

Two Members of the Aluminum-Activated Malate Transporter Family, SlALMT4 and SlALMT5, are Expressed during Fruit Development, and the Overexpression of SlALMT5 Alters Organic Acid Contents in Seeds in Tomato (Solanum lycopersicum).

PubMed

Sasaki, Takayuki; Tsuchiya, Yoshiyuki; Ariyoshi, Michiyo; Nakano, Ryohei; Ushijima, Koichiro; Kubo, Yasutaka; Mori, Izumi C; Higashiizumi, Emi; Galis, Ivan; Yamamoto, Yoko

2016-11-01

The aluminum-activated malate transporter (ALMT) family of proteins transports malate and/or inorganic anions across plant membranes. To demonstrate the possible role of ALMT genes in tomato fruit development, we focused on SlALMT4 and SlALMT5, the two major genes expressed during fruit development. Predicted proteins were classified into clade 2 of the family, many members of which localize to endomembranes. Tissue-specific gene expression was determined using transgenic tomato expressing the β-glucuronidase reporter gene controlled by their own promoters. Both the genes were expressed in vascular bundles connecting to developing seeds in fruit and in the embryo of mature seeds. Further, SlALMT5 was expressed in embryo in developing seeds in fruit. Subcellular localization of both proteins to the endoplasmic reticulum (ER) was established by transiently expressing the green fluorescent protein fusions in plant protoplasts. SlALMT5 probably localized to other endomembranes as well. Localization of SlALMT5 to the ER was also confirmed by immunoblot analysis. The transport function of both SlALMT proteins was investigated electrophysiologically in Xenopus oocytes. SlALMT5 transported malate and inorganic anions such as nitrate and chloride, but not citrate. SlALMT4 also transported malate, but the results were less consistent perhaps because it did not localize strongly to the plasma membrane. To elucidate the physiological role of SlALMT5 further, we overexpressed SlALMT5 in tomato. Compared with the wild type, overexpressors exhibited higher malate and citrate contents in mature seeds, but not in fruit. We conclude that the malate transport function of SlALMT5 expressed in developing fruit influences the organic acid contents in mature seeds. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Margins Associated with Loss of Assured Safety for Systems with Multiple Time-Dependent Failure Modes.

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

Helton, Jon C.; Brooks, Dusty Marie; Sallaberry, Cedric Jean-Marie.

Representations for margins associated with loss of assured safety (LOAS) for weak link (WL)/strong link (SL) systems involving multiple time-dependent failure modes are developed. The following topics are described: (i) defining properties for WLs and SLs, (ii) background on cumulative distribution functions (CDFs) for link failure time, link property value at link failure, and time at which LOAS occurs, (iii) CDFs for failure time margins defined by (time at which SL system fails) – (time at which WL system fails), (iv) CDFs for SL system property values at LOAS, (v) CDFs for WL/SL property value margins defined by (property valuemore » at which SL system fails) – (property value at which WL system fails), and (vi) CDFs for SL property value margins defined by (property value of failing SL at time of SL system failure) – (property value of this SL at time of WL system failure). Included in this presentation is a demonstration of a verification strategy based on defining and approximating the indicated margin results with (i) procedures based on formal integral representations and associated quadrature approximations and (ii) procedures based on algorithms for sampling-based approximations.« less

Separation of lignocelluloses from spent liquor of NSSC pulping process via adsorption.

PubMed

Dashtban, Mehdi; Gilbert, Allan; Fatehi, Pedram

2014-04-01

Hemicelluloses and lignin present in the spent liquor (SL) of neutral sulfite semichemical (NSSC) pulping process can potentially be converted into value-added products such as furfural, hydroxymethylfurfural, levulinic acid, phenols and adhesives. However, the direct conversion of hemicelluloses and lignin of SL into value-added products is uneconomical due to the dilute nature of the SL. To have a feasible downstream process for utilizing lignocelluloses of SL, the lignocelluloses should initially be separated from the SL. In this study, an adsorption process (via applying activated carbon) was considered for isolating the dissolved lignin and hemicelluloses from the SL of an NSSC pulping process. Under the optimal conditions of pH, SL/AC weight ratio, time and temperature of 5.7, 30, 360 min and 30 °C, the maximum lignin and hemicellulose adsorptions were 0.33 and 0.25 g/g on AC. The chemical oxygen demand (COD) and turbidity of the SL were decreased by 11% and 39%, respectively, as a result of lignocellulose adsorption on AC. Also, the incineration behavior of the SL-treated AC was studied with a thermo-gravimetric analysis (TGA). Copyright © 2014 Elsevier Ltd. All rights reserved.

Statistical learning as an individual ability: Theoretical perspectives and empirical evidence

PubMed Central

Siegelman, Noam; Frost, Ram

2015-01-01

Although the power of statistical learning (SL) in explaining a wide range of linguistic functions is gaining increasing support, relatively little research has focused on this theoretical construct from the perspective of individual differences. However, to be able to reliably link individual differences in a given ability such as language learning to individual differences in SL, three critical theoretical questions should be posed: Is SL a componential or unified ability? Is it nested within other general cognitive abilities? Is it a stable capacity of an individual? Following an initial mapping sentence outlining the possible dimensions of SL, we employed a battery of SL tasks in the visual and auditory modalities, using verbal and non-verbal stimuli, with adjacent and non-adjacent contingencies. SL tasks were administered along with general cognitive tasks in a within-subject design at two time points to explore our theoretical questions. We found that SL, as measured by some tasks, is a stable and reliable capacity of an individual. Moreover, we found SL to be independent of general cognitive abilities such as intelligence or working memory. However, SL is not a unified capacity, so that individual sensitivity to conditional probabilities is not uniform across modalities and stimuli. PMID:25821343

Identification, cloning and characterization of the tomato TCP transcription factor family.

PubMed

Parapunova, Violeta; Busscher, Marco; Busscher-Lange, Jacqueline; Lammers, Michiel; Karlova, Rumyana; Bovy, Arnaud G; Angenent, Gerco C; de Maagd, Ruud A

2014-06-06

TCP proteins are plant-specific transcription factors, which are known to have a wide range of functions in different plant species such as in leaf development, flower symmetry, shoot branching, and senescence. Only a small number of TCP genes has been characterised from tomato (Solanum lycopersicum). Here we report several functional features of the members of the entire family present in the tomato genome. We have identified 30 Solanum lycopersicum SlTCP genes, most of which have not been described before. Phylogenetic analysis clearly distinguishes two homology classes of the SlTCP transcription factor family - class I and class II. Class II differentiates in two subclasses, the CIN-TCP subclass and the CYC/TB1 subclass, involved in leaf development and axillary shoots formation, respectively. The expression patterns of all members were determined by quantitative PCR. Several SlTCP genes, like SlTCP12, SlTCP15 and SlTCP18 are preferentially expressed in the tomato fruit, suggesting a role during fruit development or ripening. These genes are regulated by RIN (RIPENING INHIBITOR), CNR (COLORLESS NON-RIPENING) and SlAP2a (APETALA2a) proteins, which are transcription factors with key roles in ripening. With a yeast one-hybrid assay we demonstrated that RIN binds the promoter fragments of SlTCP12, SlTCP15 and SlTCP18, and that CNR binds the SlTCP18 promoter. This data strongly suggests that these class I SlTCP proteins are involved in ripening. Furthermore, we demonstrate that SlTCPs bind the promoter fragments of members of their own family, indicating that they regulate each other. Additional yeast one-hybrid studies performed with Arabidopsis transcription factors revealed binding of the promoter fragments by proteins involved in the ethylene signal transduction pathway, contributing to the idea that these SlTCP genes are involved in the ripening process. Yeast two-hybrid data shows that SlTCP proteins can form homo and heterodimers, suggesting that they act together in order to form functional protein complexes and together regulate developmental processes in tomato. The comprehensive analysis we performed, like phylogenetic analysis, expression studies, identification of the upstream regulators and the dimerization specificity of the tomato TCP transcription factor family provides the basis for functional studies to reveal the role of this family in tomato development.

Identification, cloning and characterization of the tomato TCP transcription factor family

PubMed Central

2014-01-01

Background TCP proteins are plant-specific transcription factors, which are known to have a wide range of functions in different plant species such as in leaf development, flower symmetry, shoot branching, and senescence. Only a small number of TCP genes has been characterised from tomato (Solanum lycopersicum). Here we report several functional features of the members of the entire family present in the tomato genome. Results We have identified 30 Solanum lycopersicum SlTCP genes, most of which have not been described before. Phylogenetic analysis clearly distinguishes two homology classes of the SlTCP transcription factor family - class I and class II. Class II differentiates in two subclasses, the CIN-TCP subclass and the CYC/TB1 subclass, involved in leaf development and axillary shoots formation, respectively. The expression patterns of all members were determined by quantitative PCR. Several SlTCP genes, like SlTCP12, SlTCP15 and SlTCP18 are preferentially expressed in the tomato fruit, suggesting a role during fruit development or ripening. These genes are regulated by RIN (RIPENING INHIBITOR), CNR (COLORLESS NON-RIPENING) and SlAP2a (APETALA2a) proteins, which are transcription factors with key roles in ripening. With a yeast one-hybrid assay we demonstrated that RIN binds the promoter fragments of SlTCP12, SlTCP15 and SlTCP18, and that CNR binds the SlTCP18 promoter. This data strongly suggests that these class I SlTCP proteins are involved in ripening. Furthermore, we demonstrate that SlTCPs bind the promoter fragments of members of their own family, indicating that they regulate each other. Additional yeast one-hybrid studies performed with Arabidopsis transcription factors revealed binding of the promoter fragments by proteins involved in the ethylene signal transduction pathway, contributing to the idea that these SlTCP genes are involved in the ripening process. Yeast two-hybrid data shows that SlTCP proteins can form homo and heterodimers, suggesting that they act together in order to form functional protein complexes and together regulate developmental processes in tomato. Conclusions The comprehensive analysis we performed, like phylogenetic analysis, expression studies, identification of the upstream regulators and the dimerization specificity of the tomato TCP transcription factor family provides the basis for functional studies to reveal the role of this family in tomato development. PMID:24903607

Nongeneric positive partial transpose states of rank five in 3×3 dimensions

NASA Astrophysics Data System (ADS)

Hansen, Leif Ove; Myrheim, Jan

In 3×3 dimensions, entangled mixed states that are positive under partial transposition (PPT states) must have rank at least four. These rank four states are completely understood. We say that they have rank (4,4) since both a state ρ and its partial transpose ρP have rank four. The next problem is to understand the extremal PPT states of rank (5,5). We call two states SL⊗SL-equivalent if they are related by a product transformation. A generic rank (5,5) PPT state ρ is extremal, and both ρ and ρP have six product vectors in their ranges, and no product vectors in their kernels. The three numbers {6,6;0} are SL⊗SL-invariants that help us classify the state. There is no analytical understanding of such states. We have studied numerically a few types of nongeneric rank five PPT states, in particular, states with one or more product vectors in their kernels. We find an interesting new analytical construction of all rank four extremal PPT states, up to SL⊗SL-equivalence, where they appear as boundary states on one single five-dimensional face on the set of normalized PPT states. The interior of the face consists of rank (5,5) states with four common product vectors in their kernels, it is a simplex of separable states surrounded by entangled PPT states. We say that a state ρ is SL⊗SL-symmetric if ρ and ρP are SL⊗SL-equivalent, and is genuinely SL⊗SL-symmetric if it is SL⊗SL-equivalent to a state τ with τ=τP. Genuine SL⊗SL-symmetry implies a special form of SL⊗SL-symmetry. We have produced numerically, by a special method, a random sample of rank (5,5) SL⊗SL-symmetric states. About 50 of these are of type {6,6;0}, among those all are extremal and about half are genuinely SL⊗SL-symmetric. All these genuinely SL⊗SL-symmetric states can be transformed to have a circulant form. We find however that this is not a generic property of genuinely SL⊗SL-symmetric states. The remaining SL⊗SL-symmetric states found in the search have product vectors in their kernels, and they inspired us to study such states without regard to SL⊗SL-symmetry.

Differential expression of calcium/calmodulin-regulated SlSRs in response to abiotic and biotic stresses in tomato fruit.

PubMed

Yang, Tianbao; Peng, Hui; Whitaker, Bruce D; Jurick, Wayne M

2013-07-01

Calcium has been shown to enhance stress tolerance, maintain firmness and reduce decay in fruits. Previously we reported that seven tomato SlSRs encode calcium/calmodulin-regulated proteins, and that their expressions are developmentally regulated during fruit development and ripening, and are also responsive to ethylene. To study their expressions in response to stresses encountered during postharvest handling, tomato fruit at the mature-green stage was subjected to chilling and wounding injuries, infected with Botrytis cinerea and treated with salicylic acid or methyl jasmonate. Gene expression studies revealed that the seven SlSRs differentially respond to different stress signals. SlSR2 was the only gene upregulated by all the treatments. SlSR4 acted as a late pathogen-induced gene; it was upregulated by salicylic acid and methyl jasmonate, but downregulated by cold treatment. SlSR3L was cold- and wound-responsive and was also induced by salicylic acid. SlSR1 and SlSR1L were repressed by cold, wounding and pathogen infection, but were upregulated by salicylic acid and methyl jasmonate. Overall, results of these expression studies indicate that individual SlSRs have distinct roles in responses to the specific stress signals, and SlSRs may act as a coordinator(s) connecting calcium-mediated signaling with other stress signal transduction pathways during fruit ripening and storage. © 2013 Scandinavian Plant Physiology Society.

Identification and Functional Characterization of a Tonoplast Dicarboxylate Transporter in Tomato (Solanum lycopersicum)

PubMed Central

Liu, Ruiling; Li, Boqiang; Qin, Guozheng; Zhang, Zhanquan; Tian, Shiping

2017-01-01

Acidity plays an important role in flavor and overall organoleptic quality of fruit and is mainly due to the presence of organic acids. Understanding the molecular basis of organic acid metabolism is thus of primary importance for fruit quality improvement. Here, we cloned a putative tonoplast dicarboxylate transporter gene (SlTDT) from tomato, and submitted it to the NCBI database (GenBank accession number: KC733165). SlTDT protein contained 13 putative transmembrane domains in silico analysis. Confocal microscopic study using green fluorescent fusion proteins revealed that SlTDT was localized on tonoplast. The expression patterns of SlTDT in tomato were analyzed by RT-qPCR. The results indicated that SlTDT expressed in leaves, roots, flowers and fruits at different ripening stages, suggesting SlTDT may be associated with the development of different tissues. To further explore the function of SlTDT, we constructed both overexpression and RNAi vectors and obtained transgenic tomato plants by agrobacterium-mediated method. Gas chromatography-mass spectrometer (GC-MS) analysis showed that overexpression of SlTDT significantly increased malate content, and reduced citrate content in tomato fruit. By contrast, repression of SlTDT in tomato reduced malate content of and increased citrate content. These results indicated that SlTDT played an important role in remobilization of malate and citrate in fruit vacuoles. PMID:28261242

Identification and Functional Characterization of a Tonoplast Dicarboxylate Transporter in Tomato (Solanum lycopersicum).

PubMed

Liu, Ruiling; Li, Boqiang; Qin, Guozheng; Zhang, Zhanquan; Tian, Shiping

2017-01-01

Acidity plays an important role in flavor and overall organoleptic quality of fruit and is mainly due to the presence of organic acids. Understanding the molecular basis of organic acid metabolism is thus of primary importance for fruit quality improvement. Here, we cloned a putative tonoplast dicarboxylate transporter gene ( SlTDT ) from tomato, and submitted it to the NCBI database (GenBank accession number: KC733165). SlTDT protein contained 13 putative transmembrane domains in silico analysis. Confocal microscopic study using green fluorescent fusion proteins revealed that SlTDT was localized on tonoplast. The expression patterns of SlTDT in tomato were analyzed by RT-qPCR. The results indicated that SlTDT expressed in leaves, roots, flowers and fruits at different ripening stages, suggesting SlTDT may be associated with the development of different tissues. To further explore the function of SlTDT , we constructed both overexpression and RNAi vectors and obtained transgenic tomato plants by agrobacterium-mediated method. Gas chromatography-mass spectrometer (GC-MS) analysis showed that overexpression of SlTDT significantly increased malate content, and reduced citrate content in tomato fruit. By contrast, repression of SlTDT in tomato reduced malate content of and increased citrate content. These results indicated that SlTDT played an important role in remobilization of malate and citrate in fruit vacuoles.

Magnetic properties of the surface layer and its magnetic interaction with the interior of Nd-Fe-B sintered magnets

NASA Astrophysics Data System (ADS)

Kobayashi, Kurima; Nakamura, Michi-hide; Urushibata, Kimiko

2015-05-01

The magnetization and demagnetization mechanisms in the mechanically polished surface layers (SL) of the c-plane and a-b plane of Nd-Fe-B sintered magnets were investigated. The magnetic interaction between the SL and the interior of the magnet was clarified by using vibrating sample magnetometer measurements of a whole sample and magneto-force microscopy observations of the domain structure of the SL layer. The polishing eliminated the Nd-rich grain boundary phases, which was only about 2 nm thick, from the SL crystal grains in the sintered magnets. The a-b plane polishing caused the independent magnetic reversal of the a-b plane SL, which was about 5.5 μm thick, as in the platy samples. The coercivities (μ0Hc) of the SL were less than 0.3 T. In contrast, the c-plane polishing did not produce independent magnetic reversal of the SL, although the coercivity of bulk samples was clearly decreased by the formation of the c-plane SL. The grains in the SL should form clusters that alter the demagnetizing factors, depending on the shape of cluster as a magnetic unit. The magnetic interaction among the SL crystal grains is expected to play an important role in the coercivity mechanism of Nd-Fe-B sintered magnets.

Homology modeling reveals the structural background of the striking difference in thermal stability between two related [NiFe]hydrogenases.

PubMed

Szilágyi, András; Kovács, Kornél L; Rákhely, Gábor; Závodszky, Péter

2002-02-01

Hydrogenases are redox metalloenzymes in bacteria that catalyze the uptake or production of molecular hydrogen. Two homologous nickel-iron hydrogenases, HupSL and HydSL from the photosynthetic purple sulfur bacterium Thiocapsa roseopersicina, differ substantially in their thermal stabilities despite the high sequence similarity between them. The optimum temperature of HydSL activity is estimated to be at least 50 degrees C higher than that of HupSL. In this work, homology models of both proteins were constructed and analyzed for a number of structural properties. The comparison of the models reveals that the higher stability of HydSL can be attributed to increased inter-subunit electrostatic interactions: the homology models reliably predict that HydSL contains at least five more inter-subunit ion pairs than HupSL. The subunit interface of HydSL is more polar than that of HupSL, and it contains a few extra inter-subunit hydrogen bonds. A more optimized cavity system and amino acid replacements resulting in increased conformational rigidity may also contribute to the higher stability of HydSL. The results are in accord with the general observation that with increasing temperature, the role of electrostatic interactions in protein stability increases. Electronic supplementary material to this paper can be obtained by using the Springer Link server located at http://dx.doi.org/10.1007/s00894-001-0071-8.

Silencing SlMED18, tomato Mediator subunit 18 gene, restricts internode elongation and leaf expansion.

PubMed

Wang, Yunshu; Hu, Zongli; Zhang, Jianling; Yu, XiaoHui; Guo, Jun-E; Liang, Honglian; Liao, Changguang; Chen, Guoping

2018-02-19

Mediator complex, a conserved multi-protein, is necessary for controlling RNA polymerase II (Pol II) transcription in eukaryotes. Given little is known about them in tomato, a tomato Mediator subunit 18 gene was isolated and named SlMED18. To further explore the function of SlMED18, the transgenic tomato plants targeting SlMED18 by RNAi-mediated gene silencing were generated. The SlMED18-RNAi lines exhibited multiple developmental defects, including smaller size and slower growth rate of plant and significantly smaller compound leaves. The contents of endogenous bioactive GA 3 in SlMED18 silenced lines were slightly less than that in wild type. Furthermore, qRT-PCR analysis indicated that expression of gibberellins biosynthesis genes such as SlGACPS and SlGA20x2, auxin transport genes (PIN1, PIN4, LAX1 and LAX2) and several key regulators, KNOX1, KNOX2, PHAN and LANCEOLATE(LA), which involved in the leaf morphogenesis were significantly down-regulated in SlMED18-RNAi lines. These results illustrated that SlMED18 plays an essential role in regulating plant internode elongation and leaf expansion in tomato plants and it acts as a key positive regulator of gibberellins biosynthesis and signal transduction as well as auxin proper transport signalling. These findings are the basis for understanding the function of the individual Mediator subunits in tomato.

Spin-locking versus chemical exchange saturation transfer MRI for investigating chemical exchange process between water and labile metabolite protons.

PubMed

Jin, Tao; Autio, Joonas; Obata, Takayuki; Kim, Seong-Gi

2011-05-01

Chemical exchange saturation transfer (CEST) and spin-locking (SL) experiments were both able to probe the exchange process between protons of nonequivalent chemical environments. To compare the characteristics of the CEST and SL approaches in the study of chemical exchange effects, we performed CEST and SL experiments at varied pH and concentrated metabolite phantoms with exchangeable amide, amine, and hydroxyl protons at 9.4 T. Our results show that: (i) on-resonance SL is most sensitive to chemical exchanges in the intermediate-exchange regime and is able to detect hydroxyl and amine protons on a millimolar concentration scale. Off-resonance SL and CEST approaches are sensitive to slow-exchanging protons when an optimal SL or saturation pulse power matches the exchanging rate, respectively. (ii) Offset frequency-dependent SL and CEST spectra are very similar and can be explained well with an SL model recently developed by Trott and Palmer (J Magn Reson 2002;154:157-160). (iii) The exchange rate and population of metabolite protons can be determined from offset-dependent SL or CEST spectra or from on-resonance SL relaxation dispersion measurements. (iv) The asymmetry of the magnetization transfer ratio (MTR(asym)) is highly dependent on the choice of saturation pulse power. In the intermediate-exchange regime, MTR(asym) becomes complicated and should be interpreted with care. Copyright © 2010 Wiley-Liss, Inc.

Na2Ti6O13@TiO2 core-shell nanorods with controllable mesoporous shells and their enhanced photocatalytic performance

NASA Astrophysics Data System (ADS)

Zhou, Xuefan; Zhong, Donglin; Luo, Hang; Pan, Jun; Zhang, Dou

2018-01-01

In this study, dispersive and free-standing Na2Ti6O13 nanorods with diameter of about 500 nm and length of about 10 μm were synthesized by the molten salt method. The Na2Ti6O13@TiO2 (denoted as TTO) core-shell nanorods were fabricated by a versatile kinetics controlled coating method. The TiO2 shells were uniform and mesoporous with exposed {101} facets. The thickness of TiO2 shells can be well controlled by the content of Ti(OC4H9)4, ranging from 0 nm, 15 nm, 60 nm to 70 nm corresponding to Na2Ti6O13, 0.25-TTO, 0.50-TTO and 0.75-TTO nanorods respectively. The crystalline phases, microstructure, porosity, photoabsorption and photocatalytic performance of all the samples were investigated systematically. The nanoscale heterojunction structure between Na2Ti6O13 and TiO2, reductive TiO2 {101} facets and high aspect ratio Na2Ti6O13 nanorods resulted in the enhanced photocatalytic performance of TTO nanorods. The optimized thickness of TiO2 shells were about 60 nm for 0.50-TTO nanorods, which possessed superior BET surface area, optical absorption and photocatalytic performance.

Micro-Raman investigations of InN-GaN core-shell nanowires on Si (111) substrate

NASA Astrophysics Data System (ADS)

Sangeetha, P.; Jeganathan, K.; Ramakrishnan, V.

2013-06-01

The electron-phonon interactions in InN-GaN core-shell nanowires grown by plasma assisted- molecular beam epitaxy (MBE) on Si (111) substrate have been analysed using micro-Raman spectroscopic technique with the excitation wavelength of 633, 488 and 325 nm. The Raman scattering at 633 nm reveals the characteristic E2 (high) and A1 (LO) phonon mode of InN core at 490 and 590 cm-1 respectively and E2 (high) phonon mode of GaN shell at 573 cm-1. The free carrier concentration of InN core is found to be low in the order ˜ 1016 cm-3 due to the screening of charge carriers by thin GaN shell. Diameter of InN core evaluated using the spatial correlation model is consistent with the transmission electron microscopic measurement of ˜15 nm. The phonon-life time of core-shell nanowire structure is estimated to be ˜0.4 ps. The micro-Raman mapping and its corresponding localised spectra for 325 nm excitation exhibit intense E2 (high) phonon mode of GaN shell at 573 cm-1 as the decrease of laser interaction length and the signal intensity is quenched at the voids due to high spacing of NWs.

Dynamic model of open shell structures buried in poroelastic soils

NASA Astrophysics Data System (ADS)

Bordón, J. D. R.; Aznárez, J. J.; Maeso, O.

2017-08-01

This paper is concerned with a three-dimensional time harmonic model of open shell structures buried in poroelastic soils. It combines the dual boundary element method (DBEM) for treating the soil and shell finite elements for modelling the structure, leading to a simple and efficient representation of buried open shell structures. A new fully regularised hypersingular boundary integral equation (HBIE) has been developed to this aim, which is then used to build the pair of dual BIEs necessary to formulate the DBEM for Biot poroelasticity. The new regularised HBIE is validated against a problem with analytical solution. The model is used in a wave diffraction problem in order to show its effectiveness. It offers excellent agreement for length to thickness ratios greater than 10, and relatively coarse meshes. The model is also applied to the calculation of impedances of bucket foundations. It is found that all impedances except the torsional one depend considerably on hydraulic conductivity within the typical frequency range of interest of offshore wind turbines.

Pattern of relative growth in cockle Anadara antiquata in Ihamahu coastal waters, Central Maluku

NASA Astrophysics Data System (ADS)

Siahainenia, L.; Tuhumury, S. F.; Uneputty, P. A.; Tuhumury, N. C.

2018-03-01

Anadara antiquata is economically important species for fisheries and belong to phylum mollusc which also found in Maluku. However, the density of population begins to decrease recently due to high exploitation by people. The objective of the present study was to analyze relative growth pattern of A. antiquata including size distribution and growth pattern based on shell dimensions. The study was conducted from December 2016 to February 2017 in Ihamahu coastal waters. Data were collected by using purposive random sampling. All the individuals of A. antiquata found were measured the length, width and height by using a vernier caliper to the nearest 0.01mm. Data were analyzed by using SPSS 20 and Microsoft Excel software. The results indicated that the A. antiquata mostly found in seagrass bed with a muddy substrate. The size distribution of shell dimensions was different during sampling. Overall, the length ranged from 15.87 mm to 57.5 mm, the width from 15.50 mm to 48.60 mm and the height was from 9.36 mm to 35.9 mm. The population of A. antiquata consisted of juvenile and mature size. The mature size (> 30 mm) was more dominant in the population. The A. antiquata showed allometric relative growth pattern based on shell dimensions.

Ontogeny of juvenile freshwater pearl mussels, Margaritifera margaritifera (Bivalvia: Margaritiferidae)

PubMed Central

Ramsey, Andrew D.; Moorkens, Evelyn A.; Souch, Graham; Barnhart, M. Christopher

2018-01-01

The gills of juvenile freshwater bivalves undergo a complex morphogenesis that may correlate with changes in feeding ecology, but ontogenic studies on juvenile mussels are rare. Scanning electron microscopy was used to examine the ultrastructure and ontogeny of 117 juvenile freshwater pearl mussels (Margaritifera margaritifera) ranging in age from 1–44 months and length from 0.49–8.90 mm. Three stages of gill development are described. In Stage 1 (5–9 inner demibranch filaments), only unreflected inner demibranch filaments were present. In Stage 2 (9–17 inner demibranch filaments), inner demibranch filaments began to reflect when shell length exceeded 1.13 mm, at 13–16 months old. Reflection began in medial filaments and then proceeded anterior and posterior. In Stage 3 (28–94 inner demibranch filaments), outer demibranch filaments began developing at shell length > 3.1 mm and about 34 months of age. The oral groove on the inner demibranch was first observed in 34 month old specimens > 2.66 mm but was never observed on the outer demibranch. Shell length (R2 = 0.99) was a better predictor of developmental stage compared to age (R2 = 0.84). The full suite of gill ciliation was present on filaments in all stages. Interfilamentary distance averaged 31.3 μm and did not change with age (4–44 months) or with size (0.75–8.9 mm). Distance between laterofrontal cirri couplets averaged 1.54 μm and did not change significantly with size or age. Labial palp primordia were present in even the youngest individuals but ciliature became more diverse in more developed individuals. Information presented here is valuable to captive rearing programmes as it provides insight in to when juveniles may be particularly vulnerable to stressors due to specific ontogenic changes. The data are compared with two other recent studies of Margaritifera development. PMID:29590123

Primitive ideals of C q [ SL(3)

NASA Astrophysics Data System (ADS)

Hodges, Timothy J.; Levasseur, Thierry

1993-10-01

The primitive ideals of the Hopf algebra C q [ SL(3)] are classified. In particular it is shown that the orbits in Prim C q [ SL(3)] under the action of the representation group H ≅ C *× C * are parameterized naturally by W×W, where W is the associated Weyl group. It is shown that there is a natural one-to-one correspondence between primitive ideals of C q [ SL(3)] and symplectic leaves of the associated Poisson algebraic group SL(3, C).

Increased blood flow and vasculature in solar lentigo.

PubMed

Hasegawa, Kiyotaka; Fujiwara, Rumiko; Sato, Kiyoshi; Park, Ji-Youn; Kim, Sang Jin; Kim, Misun; Kang, Hee Young

2016-10-01

Solar lentigo (SL) is a hallmark of ultraviolet (UV)-induced photoaged skin and growing evidence implicates blood vessels in UV-associated pigmentation. In this study, we investigated whether the vasculatures are modified in SL. Twenty-five women with facial SL were enrolled and colorimetric and blood flow studies were performed. There was a significant increase in erythema which was associated with increased blood flow in the lesional skin compared with perilesional normal skin. Immunohistochemical studies with 24 facial SL biopsies consistently revealed a significant increase in vessel density accompanied by increased levels of vascular endothelial growth factor expression. CD68 immunoreactivity was significantly higher in lesional skin suggesting increased macrophage infiltration in SL. In conclusion, SL is characterized by increased blood flow and vasculature. These findings suggest the possible influence of the characteristics of vasculature on development of SL. © 2016 Japanese Dermatological Association.

7SL RNA in Vertebrate Red Blood Cells.

PubMed

Talhouarne, Gaëlle J S; Gall, Joseph G

2018-04-23

We report that 7SL, the RNA component of the signal recognition particle (SRP), is an abundant ncRNA in mature red blood cells (RBCs) of human, mouse, and the frog Xenopus. 7SL RNA in RBCs is not associated with the canonical proteins of the SRP. Instead, it co-immunoprecipitates from a lysate of RBCs with a number of membrane-binding proteins. Human and mouse RBCs also contain a previously undescribed 68 nt RNA, sRN7SL, derived from the "S domain" of 7SL RNA. We discuss the possibility that 7SL RNA is selectively protected from nucleases by association with the RBC membrane. Because 7SL is not associated with the canonical proteins of the SRP, it could represent a non-functional remnant of the protein synthetic machinery. Alternatively, it could play a new, as yet undefined role in RBC metabolism. Published by Cold Spring Harbor Laboratory Press for the RNA Society.

[Pregnancy-related and work-related sick leave of pregnant women].

PubMed

Tophøj, A; Mortensen, J T

1999-09-06

Pregnant women are allowed sick leave (SL) due to obstetrical or occupational risk factors. The aim was to describe reasons for SL during pregnancy. Pregnant women in a Danish county applying for SL were consecutively included in the study during 12 months in 1991-92. Data were obtained by questionnaires mailed to the women and their medical doctors. Of 1483 pregnant women on SL, 994 participated. Approximately 96% were on SL due to obstetrical risk factors. Occupational factors contributed to SL in at least 50% of the cases, mainly when working in a standing or walking position or when lifting. The women were rarely replaced in other jobs before leaving work. On average the women were absent for 83 days before official pregnancy leave started. Although SL during pregnancy is overwhelmingly due to obstetrical risk factors, occupational factors often contribute. Occupational Health and Safety Organizations are rarely involved at the workplace before issuing a sick leave certificate.

Sedentary lifestyle in individuals with hypertension.

PubMed

Martins, Larissa Castelo Guedes; Lopes, Marcos Venícios de Oliveira; Guedes, Nirla Gomes; Nunes, Marília Mendes; Diniz, Camila Maciel; Carvalho, Priscilla Magalhães de Oliveira

2015-01-01

to identify the prevalence of nursing diagnosis Sedentary lifestyle (SL) and to analyze its association with clinical indicators (CI) and related factors (RF) in patients with hypertension. cross-sectional study with 285 patients with hypertension at a reference center for outpatient care in Northeastern Brazil. To collect data it was used an instrument based on operational defi nitions of the CI and RF previously validated. Four nurses rated SL as present or absent. To evaluate the association between CI and RF with the presence of SL it was applied the chi-square test. The prevalence ratio and confi dence interval was calculated to verify the magnitude of the effect between RF and SL. SL was identifi ed in 55.8% of the sample. Five IC and six RF showed a signifi cant association with SL. the study identifi es main indicators for inference of SL as well as their possible causal factors among people with hypertension.

Variances and uncertainties of the sample laboratory-to-laboratory variance (S(L)2) and standard deviation (S(L)) associated with an interlaboratory study.

PubMed

McClure, Foster D; Lee, Jung K

2012-01-01

The validation process for an analytical method usually employs an interlaboratory study conducted as a balanced completely randomized model involving a specified number of randomly chosen laboratories, each analyzing a specified number of randomly allocated replicates. For such studies, formulas to obtain approximate unbiased estimates of the variance and uncertainty of the sample laboratory-to-laboratory (lab-to-lab) STD (S(L)) have been developed primarily to account for the uncertainty of S(L) when there is a need to develop an uncertainty budget that includes the uncertainty of S(L). For the sake of completeness on this topic, formulas to estimate the variance and uncertainty of the sample lab-to-lab variance (S(L)2) were also developed. In some cases, it was necessary to derive the formulas based on an approximate distribution for S(L)2.

Effects of ocean acidification with pCO2 diurnal fluctuations on survival and larval shell formation of Ezo abalone, Haliotis discus hannai.

PubMed

Onitsuka, Toshihiro; Takami, Hideki; Muraoka, Daisuke; Matsumoto, Yukio; Nakatsubo, Ayumi; Kimura, Ryo; Ono, Tsuneo; Nojiri, Yukihiro

2018-03-01

This study assessed the effects of constant and diurnally fluctuating pCO 2 on development and shell formation of larval abalone Haliotis discus hannai. The larvae was exposed to different pCO 2 conditions; constant [450, 800, or 1200 μatm in the first experiment (Exp. I), 450 or 780 μatm in the second experiment (Exp. II)] or diurnally fluctuating pCO 2 (800 ± 400 or 1200 ± 400 μatm in Exp. I, 450 ± 80, 780 ± 200 or 780 ± 400 μatm in Exp. II). Mortality, malformation rates or shell length of larval abalone were not significantly different among the 450, 800, and 800 ± 400 μatm pCO 2 treatments. Meanwhile, significantly higher malformation rates and smaller shells were detected in the 1200 and 1200 ± 400 μatm pCO 2 treatments than in the 450 μatm pCO 2 treatment. The negative impacts were greater in the 1200 ± 400 μatm than in the 1200 μatm. Shell length and malformation rate of larval abalone were related with aragonite saturation state (Ω-aragonite) in experimental seawater, and greatly changed around 1.1 of Ω-aragonite which corresponded to 1000-1300 μatm pCO 2 . These results indicate that there is a pCO 2 threshold associated with Ω-aragonite in the seawater, and that pCO 2 fluctuations produce additional negative impacts on abalone when above the threshold. Clear relationships were detected between abalone fitness and the integrated pCO 2 value over the threshold, indicating that the effects of OA on development and shell formation of larval abalone can be determined by intensity and time of exposure to pCO 2 over the threshold. Copyright © 2017 Elsevier Ltd. All rights reserved.

49 CFR Appendix B to Part 229 - Schedule of Civil Penalties 1

Code of Federal Regulations, 2012 CFR

2012-10-01

... 1,000 2,000 (f) Replace Form FRA F 6180.49A by April 2 or July 3 (g) Secondary record of the... 229.75Wheel and tire defects: (a),(d) Slid flat or shelled spot(s): (1) One spot 21/2″ or more but less than 3″ in length 2,500 5,000 (2) One spot 3″ or more in length 5,000 7,500 (3) Two adjoining...

49 CFR Appendix B to Part 229 - Schedule of Civil Penalties 1

Code of Federal Regulations, 2014 CFR

2014-10-01

... 1,000 2,000 (f) Replace Form FRA F 6180.49A by April 2 or July 3 (g) Secondary record of the... 229.75Wheel and tire defects: (a),(d) Slid flat or shelled spot(s): (1) One spot 21/2″ or more but less than 3″ in length 2,500 5,000 (2) One spot 3″ or more in length 5,000 7,500 (3) Two adjoining...

49 CFR Appendix B to Part 229 - Schedule of Civil Penalties 1

Code of Federal Regulations, 2013 CFR

2013-10-01

... 1,000 2,000 (f) Replace Form FRA F 6180.49A by April 2 or July 3 (g) Secondary record of the... 229.75Wheel and tire defects: (a),(d) Slid flat or shelled spot(s): (1) One spot 21/2″ or more but less than 3″ in length 2,500 5,000 (2) One spot 3″ or more in length 5,000 7,500 (3) Two adjoining...

DWARF 53 acts as a repressor of strigolactone signalling in rice

NASA Astrophysics Data System (ADS)

Jiang, Liang; Liu, Xue; Xiong, Guosheng; Liu, Huihui; Chen, Fulu; Wang, Lei; Meng, Xiangbing; Liu, Guifu; Yu, Hong; Yuan, Yundong; Yi, Wei; Zhao, Lihua; Ma, Honglei; He, Yuanzheng; Wu, Zhongshan; Melcher, Karsten; Qian, Qian; Xu, H. Eric; Wang, Yonghong; Li, Jiayang

2013-12-01

Strigolactones (SLs) are a group of newly identified plant hormones that control plant shoot branching. SL signalling requires the hormone-dependent interaction of DWARF 14 (D14), a probable candidate SL receptor, with DWARF 3 (D3), an F-box component of the Skp-Cullin-F-box (SCF) E3 ubiquitin ligase complex. Here we report the characterization of a dominant SL-insensitive rice (Oryza sativa) mutant dwarf 53 (d53) and the cloning of D53, which encodes a substrate of the SCFD3 ubiquitination complex and functions as a repressor of SL signalling. Treatments with GR24, a synthetic SL analogue, cause D53 degradation via the proteasome in a manner that requires D14 and the SCFD3 ubiquitin ligase, whereas the dominant form of D53 is resistant to SL-mediated degradation. Moreover, D53 can interact with transcriptional co-repressors known as TOPLESS-RELATED PROTEINS. Our results suggest a model of SL signalling that involves SL-dependent degradation of the D53 repressor mediated by the D14-D3 complex.

Overexpression of SlGRAS40 in Tomato Enhances Tolerance to Abiotic Stresses and Influences Auxin and Gibberellin Signaling

PubMed Central

Liu, Yudong; Huang, Wei; Xian, Zhiqiang; Hu, Nan; Lin, Dongbo; Ren, Hua; Chen, Jingxuan; Su, Deding; Li, Zhengguo

2017-01-01

Abiotic stresses are major environmental factors that inhibit plant growth and development impacting crop productivity. GRAS transcription factors play critical and diverse roles in plant development and abiotic stress. In this study, SlGRAS40, a member of the tomato (Solanum lycopersicum) GRAS family, was functionally characterized. In wild-type (WT) tomato, SlGRAS40 was upregulated by abiotic stress induced by treatment with D-mannitol, NaCl, or H2O2. Transgenic tomato plants overexpressing SlGRAS40 (SlGRAS40-OE) were more tolerant of drought and salt stress than WT. SlGRAS40-OE plants displayed pleiotropic phenotypes reminiscent of those resulting from altered auxin and/or gibberellin signaling. A comparison of WT and SlGRAS40-OE transcriptomes showed that the expression of a large number of genes involved in hormone signaling and stress responses were modified. Our study of SlGRAS40 protein provides evidence of how another GRAS plays roles in resisting abiotic stress and regulating auxin and gibberellin signaling during vegetative and reproductive growth in tomato. PMID:29018467

Efficient photoassociation of ultracold cesium atoms with picosecond pulse laser

NASA Astrophysics Data System (ADS)

Hai, Yang; Hu, Xue-Jin; Li, Jing-Lun; Cong, Shu-Lin

2017-08-01

We investigate theoretically the formation of ultracold Cs2 molecules via photoassociation (PA) with three kinds of pulses (the Gaussian pulse, the asymmetric shaped laser pulse SL1 with a large rising time and a small falling time and the asymmetric shaped laser pulse SL2 with a small rising time and a large falling time). For the three kinds of pulses, the final population on vibrational levels from v‧ = 120 to 175 of the excited state displays a regular oscillation change with pulse width and interaction strength, and a high PA efficiency can be achieved with optimised parameters. The PA efficiency in the excited state steered by the SL1-pulse (SL2-pulse) train with optimised parameters which is composed of four SL1 (SL2) pulses is 1.74 times as much as that by the single SL1 (SL2) pulse due to the population accumulation effect. Moreover, a dump laser is employed to transfer the excited molecules from the excited state to the vibrational level v″ = 12 of the ground state to obtain stable molecules.

Plasmonic Resonances in Self-Assembled Reduced Symmetry Gold Nanorod Structures (POSTPRINT)

DTIC Science & Technology

2013-05-01

distances, s/l < 0.06, where s is the gap distance and l is the length of the nanoparticles.21,26 Such a small gap (0.5−3 nm) increases coulomb ...Halas, N. J.; Lal, S.; Chang, W.-S.; Link, S.; Nordlander, P. Chem. Rev. 2011, 111, 3913−3961. (13) Luo, Y.; Lei , D. Y.; Maier, S. A.; Pendry, J. B. ACS...Liang, Y.; Wang, J.; Lin, H.-Q. ACS Nano 2011, 5, 5976−5986. (25) Abb, M.; Wang, Y.; Albella, P.; de Groot, C. H.; Aizpurua, J.; Muskens, O. L. ACS

Torque expression in self-ligating orthodontic brackets and conventionally ligated brackets: A systematic review

PubMed Central

Al-Thomali, Yousef; Mohamed, Roshan-Noor; Basha, Sakeenabi

2017-01-01

Background To evaluate the torque expression of self ligating (SL) orthodontic brackets and conventionally ligated brackets and the torque expression in active and passive SL brackets. Material and Methods Our systematic search included MEDLINE, EMBASE, CINAHL, PsychINFO, Scopus, and key journals and review articles; the date of the last search was April 4th 2016. We graded the methodological quality of the studies by means of the Quality Assessment Tool for Quantitative Studies, developed for the Effective Public Health Practice Project (EPHPP). Results In total, 87 studies were identified for screening, and 9 studies were eligible. The quality assessment rated one of the study as being of strong quality, 7 (77.78%) of these studies as being of moderate quality. Three out of 7 studies which compared SL and conventionally ligated brackets showed, conventionally ligated brackets with highest torque expression compared to SL brackets. Badawi showed active SL brackets with highest torque expression compared to passive SL brackets. Major and Brauchli showed no significant differences in torque expression of active and passive SL brackets. Conclusions Conventionally ligated brackets presented with highest torque expression compared to SL brackets. Minor difference was recorded in a torque expression of active and passive SL brackets. Key words:Systematic review, self ligation, torque expression, conventional ligation. PMID:28149476

Torque expression in self-ligating orthodontic brackets and conventionally ligated brackets: A systematic review.

PubMed

Al-Thomali, Yousef; Mohamed, Roshan-Noor; Basha, Sakeenabi

2017-01-01

To evaluate the torque expression of self ligating (SL) orthodontic brackets and conventionally ligated brackets and the torque expression in active and passive SL brackets. Our systematic search included MEDLINE, EMBASE, CINAHL, PsychINFO, Scopus, and key journals and review articles; the date of the last search was April 4th 2016. We graded the methodological quality of the studies by means of the Quality Assessment Tool for Quantitative Studies, developed for the Effective Public Health Practice Project (EPHPP). In total, 87 studies were identified for screening, and 9 studies were eligible. The quality assessment rated one of the study as being of strong quality, 7 (77.78%) of these studies as being of moderate quality. Three out of 7 studies which compared SL and conventionally ligated brackets showed, conventionally ligated brackets with highest torque expression compared to SL brackets. Badawi showed active SL brackets with highest torque expression compared to passive SL brackets. Major and Brauchli showed no significant differences in torque expression of active and passive SL brackets. Conventionally ligated brackets presented with highest torque expression compared to SL brackets. Minor difference was recorded in a torque expression of active and passive SL brackets. Key words: Systematic review, self ligation, torque expression, conventional ligation.

Purification, Characterization, and Functional Role of a Novel Extracellular Protease from Pleurotus ostreatus

PubMed Central

Palmieri, Gianna; Bianco, Carmen; Cennamo, Giovanna; Giardina, Paola; Marino, Gennaro; Monti, Maria; Sannia, Giovanni

2001-01-01

A new extracellular protease (PoSl; Pleurotus ostreatus subtilisin-like protease) from P. ostreatus culture broth has been purified and characterized. PoSl is a monomeric glycoprotein with a molecular mass of 75 kDa, a pI of 4.5, and an optimum pH in the alkaline range. The inhibitory profile indicates that PoSl is a serine protease. The N-terminal and three tryptic peptide sequences of PoSl have been determined. The homology of one internal peptide with conserved sequence around the Asp residue of the catalytic triad in the subtilase family suggests that PoSl is a subtilisin-like protease. This hypothesis is further supported by the finding that PoSl hydrolysis sites of the insulin B chain match those of subtilisin. PoSl activity is positively affected by calcium. A 10-fold decrease in the Km value in the presence of calcium ions can reflect an induced structural change in the substrate recognition site region. Furthermore, Ca2+ binding slows PoSl autolysis, triggering the protein to form a more compact structure. These effects have already been observed for subtilisin and other serine proteases. Moreover, PoSl protease seems to play a key role in the regulation of P. ostreatus laccase activity by degrading and/or activating different isoenzymes. PMID:11375191

Treatment of chronic scapholunate dissociation with tenodesis: A systematic review.

PubMed

Athlani, L; Pauchard, N; Detammaecker, R; Huguet, S; Lombard, J; Dap, F; Dautel, G

2018-04-01

Scapholunate (SL) instability is the most common dissociative carpal instability condition. It is the most frequent cause of wrist osteoarthritis, defined as scapholunate advanced collapse or SLAC wrist. Familiarity with the SL ligament complex is required to understand the various features of SL instability. Damage to the SL interosseous ligament is the main prerequisite for SL instability; however the extrinsic, palmar and dorsal ligaments of the carpus also come into play. When more than 6 weeks has passed since the initial injury event, SL instability is considered chronic because ligament healing is no longer possible. Before osteoarthritis sets in and when the SL instability is still reducible (scaphoid can be reverticalized), ligament reconstruction surgery is indicated. Since the end of the 1970s, various ligament reconstruction or tenodesis techniques have been described. These techniques are used in cases of chronic, dynamic or static reducible SL instability, when no repairable ligament stump and no chondral lesions are present. The aim is to correct the SL instability using a free or pedicled tendon graft to reduce pain while limiting the loss of mobility and protecting against osteoarthritis-related collapse in the long-term. We will perform a systematic review of the various tenodesis techniques available in the literature. Copyright © 2017 SFCM. Published by Elsevier Masson SAS. All rights reserved.

The intracellular nucleotide binding leucine-rich repeat receptor - SlNRC4a enhances immune signaling elicited by extracellular perception.

PubMed

Leibman-Markus, Meirav; Pizarro, Lorena; Schuster, Silvia; Lin, Z J Daniel; Gershony, Ofir; Bar, Maya; Coaker, Gitta; Avni, Adi

2018-05-23

Plant recognition and defense against pathogens employs a two-tiered perception system. Surface localized pattern recognition receptors (PRRs) act to recognize microbial features, while intracellular nucleotide binding leucine-rich repeat receptors (NLRs) directly or indirectly recognize pathogen effectors inside host cells. Employing the tomato PRR LeEIX2/EIX model system, we explored the molecular mechanism of signaling pathways. We identified an NLR that can associate with LeEIX2, termed SlNRC4a (NB-LRR Required for HR-associated Cell death-4). Co-immunoprecipitation demonstrates that SlNRC4a is able to associate with different PRRs. Physiological assays with specific elicitors revealed that SlNRC4a generally alters PRR-mediated responses. SlNRC4a overexpression enhances defense responses while silencing SlNRC4 reduces plant immunity. Moreover, the coiled-coil domain of SlNRC4a is able to associate with LeEIX2 and is sufficient to enhance responses upon EIX perception. Based on these findings, we propose that SlNRC4a acts as a non-canonical positive regulator of immunity mediated by diverse PRRs. Thus, SlNRC4a could link both intracellular and extracellular immune perception. This article is protected by copyright. All rights reserved.

The pectinases from Sphenophorus levis: Potential for biotechnological applications.

PubMed

Habrylo, Olivier; Evangelista, Danilo Elton; Castilho, Priscila Vasques; Pelloux, Jérôme; Henrique-Silva, Flávio

2018-06-01

Pectinases represent about one fifth of the enzyme worldwide market due their wide range of biotechnological applications. Current commercial pectinases are exclusively obtained from microbial sources, but here we report a pectin methylesterase (Sl-PME) and an endo-polygalacturonase (Sl-EPG) bioprospected from the sugarcane weevil, Sphenophorus levis, which revealed good potential for industrial applications. Sl-PME and Sl-EPG were overexpressed in Pichia pastoris, purified and enzymatically characterized. Sl-EPG presents optimal activity at pH 4-5 and 50 °C, showing that it can be used for juice extraction and clarification. On the other hand, Sl-PME presents optimal activity at pH 6-8 and 40 °C, and thus, suitable for both acidic and alkaline processing, such as coffee and tea fermentation. Sl-EPG shows V max  = 3.23 mM/min, K M  = 2.4 g/L and k cat  = 418.6 s -1 . While Sl-PME shows V max  = 0.14 mM/min, K M  = 4.1 g/L and k cat  = 1.7 s -1 . A PG inhibitor (PGIP2) weakly interfered in the Sl-EPG activity and Sl-PME was not affected by a usual PME inhibitor. Moreover, these enzymes manifested synergistic action towards methylesterified pectin. Here, we propose these enzymes as novel alternative tools for the current commercial pectinases. Copyright © 2018 Elsevier B.V. All rights reserved.

Comparison of slitlamp optical coherence tomography and scanning peripheral anterior chamber depth analyzer to evaluate angle closure in Asian eyes.

PubMed

Wong, Hon-Tym; Chua, Jocelyn L L; Sakata, Lisandro M; Wong, Melissa H Y; Aung, Han T; Aung, Tin

2009-05-01

To evaluate the effectiveness of slitlamp optical coherence tomography (SL-OCT) and Scanning Peripheral Anterior Chamber depth analyzer (SPAC) in detecting angle closure, using gonioscopy as the reference standard. A total of 153 subjects underwent gonioscopy, SL-OCT, and SPAC. The anterior chamber angle (ACA) was classified as closed on gonioscopy if the posterior trabecular meshwork could not be seen; with SL-OCT, closure was determined by contact between the iris and angle wall anterior to the scleral spur; and with SPAC by a numerical grade of 5 or fewer and/or a categorical grade of suspect or potential. A closed ACA was identified in 51 eyes with gonioscopy, 86 eyes with SL-OCT, and 61 eyes with SPAC (gonioscopy vs SL-OCT, P < .001; gonioscopy vs SPAC, P = .10; SL-OCT vs SPAC, P < .001; McNemar test). Of the 51 eyes with a closed ACA on gonioscopy, SL-OCT detected a closed ACA in 43, whereas SPAC identified 41 (P = .79). An open angle in all 4 quadrants was observed in 102 eyes with gonioscopy, but SL-OCT and SPAC identified 43 and 20 of these eyes, respectively, as having angle closure. The overall sensitivity and specificity for SL-OCT were 84% and 58% vs 80% and 80% for SPAC. Using gonioscopy as the reference, SL-OCT and SPAC showed good sensitivity for detecting eyes at risk of angle closure.

Service-Learning Enhances Physical Therapy Students' Ability to Examine Fall Risk in Older Adults.

PubMed

Nordon-Craft, Amy; Schwarz, Brandy; Kowalewski, Victoria; Hartos, Jessica; Jurado Severance, Jennifer; Bugnariu, Nicoleta

2017-01-01

Service-learning (SL) is one educational methodology that provides students opportunities to practice and refine affective, cognitive and psychomotor skills in a community-based setting. The aims of this study were: 1) to investigate the impact of SL on physical therapy (PT) students' attitudes and perceived clinical competence when working with older adults, and 2) to evaluate the difference between perceptions of students who developed and implemented the SL activity vs those who implemented only. Eighty PT students, (from two consecutive cohorts) enrolled in a first-year geriatrics course, participated in this study. The first cohort designed and implemented the SL activities, while the second cohort only implemented these activities. Student self-perceived anxiety, confidence, knowledge and skills were assessed by pre- and post-SL surveys using a 5- point Likert-like scale. Both cohorts reported similar anxiety and confidence levels pre-SL. For both cohorts, with the exception of one item, all responses to anxiety items significantly decreased from pre- to post-SL. All students' confidence levels for assessing and mitigating fall risk in older adults increased post-SL (p<0.01). Moreover, students in cohort 1, who designed and delivered SL activities, expressed self-perceived improvement in their ability to interpret results of evaluations, to determine type and severity of balance impairments, and to serve a geriatric population (p<0.05) compared to students in cohort 2 who only implemented the activities. Embedding SL into a geriatrics course decreased self-perceived anxiety and improved student confidence regarding working with older adults. Also, empowering students to be actively involved in the design and implementation of SL increased self-perceived ability in interpreting results from assessments.

Solid lipid dispersions: potential delivery system for functional ingredients in foods.

PubMed

Asumadu-Mensah, Aboagyewa; Smith, Kevin W; Ribeiro, Henelyta S

2013-07-01

Structured solid lipid (SL) systems have the advantages of long-term physical stability, low surfactant concentrations, and may exhibit controlled release of active ingredients. In this research work, the potential use of high-melting SLs for the production of the above structured SL carrier systems was investigated. Dispersions containing either SL or blend of solid lipid and oil (SL+O) were produced by a hot melt high-pressure homogenization method. Experiments involved the use of 3 different SLs for the disperse phase: stearic acid, candelilla wax and carnauba wax. Sunflower oil was incorporated in the disperse phase for the production of the dispersions containing lipid and oil. In order to evaluate the practical aspects of structured particles, analytical techniques were used including: static light scattering to measure particle sizes, transmission electron microscopy (TEM) for investigating particle morphology and differential scanning calorimetry (DSC) to investigate the crystallization behavior of lipids in bulk and in dispersions. Results showed different mean particle sizes depending on the type of lipid used in the disperse phase. Particle sizes for the 3 lipids were: stearic acid (SL: 195 ± 2.5 nm; SL+O: 138 ± 6.0 nm); candelilla wax (SL: 178 ± 1.7 nm; SL+O: 144 ± 0.6 nm); carnauba wax (SL: 303 ± 1.5 nm; SL+O: 295 ± 5.0 nm). TEM results gave an insight into the practical morphology, showing plate-like and needle-like structures. DSC investigations also revealed that SL dispersions melted and crystallized at lower temperatures than the bulk. This decrease can be explained by the small particle sizes of the dispersion, the high-specific surface area, and the presence of a surfactant. © 2013 Institute of Food Technologists®

Metal Artifact Reduction With MAVRIC SL at 3-T MRI in Patients With Hip Arthroplasty

PubMed Central

Choi, Soo-Jung; Koch, Kevin M.; Hargreaves, Brian A.; Stevens, Kathryn J.; Gold, Garry E.

2015-01-01

OBJECTIVE The objective of our study was to compare the multiacquisition variable-resonance image combination selective (MAVRIC SL) sequence with the 2D fast spin-echo (FSE) sequence for metal artifact reduction on 3-T MRI in patients with hip arthroplasty (HA). MATERIALS AND METHODS Matched 2D FSE and MAVRIC SL images of 21 hips (19 patients with HA) were included in the study group. Paired image sets, composed of 13 coronal and 12 axial slices (total, 25 image sets), of the 21 hips were evaluated. For quantitative analysis, the artifact area was measured at the level of the hip and femur. For qualitative analysis, two musculoskeletal radiologists independently compared paired 2D FSE and MAVRIC SL sets in terms of artifacts, depiction of anatomic detail, level of diagnostic confidence, and detection of abnormal findings. RESULTS The measured artifact area was significantly smaller (p < 0.05) on MAVRIC SL than 2D FSE at both the level of hip (59.9% reduction with MAVRIC SL) and femur (31.3% reduction with MAVRIC SL). The artifact score was also significantly decreased (p < 0.0001) with MAVRIC SL compared with 2D FSE for both reviewers. The hip joint capsule and the tendon attachment sites of the obturator externus and iliopsoas muscles were better depicted with MAVRIC SL than 2D FSE (p < 0.0125). Abnormal findings were significantly better shown on MAVRIC SL imaging compared with 2D FSE imaging (p < 0.0001). CONCLUSION The MAVRIC SL sequence can significantly reduce metal artifact on 3-T MRI compared with the 2D FSE sequence and can increase diagnostic confidence of 3-T MRI in patients with total HA. PMID:25539249

Broad-spectrum neutralization of avian influenza viruses by sialylated human milk oligosaccharides: in vivo assessment of 3'-sialyllactose against H9N2 in chickens.

PubMed

Pandey, Ramesh Prasad; Kim, Dae Hee; Woo, Jinsuk; Song, Jaeyoung; Jang, Sang Ho; Kim, Joon Bae; Cheong, Kwang Myun; Oh, Jin Sik; Sohng, Jae Kyung

2018-02-07

Two sialylated human milk oligosaccharides (SHMOs) 3'-sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL) were accessed for their possible antiviral activity against six different subtypes of thirteen avian influenza (AI) viruses in vitro. 3'-SL exhibited promising antiviral activity against almost all subtypes of tested AI viruses in hemagglutination inhibition assay, whereas 6'-SL showed activity against few selected H1N1, H1N2, and H3N2 subtype strains. 3'-SL has minimum inhibitory concentration values of 15.62 mM or less in more than half of the viruses examined. 3'-SL also showed effective inactivation of H9N2 Korea isolate (A/Chicken/Korea/MS96/1996) at 12.5 mM concentration in Madin Darby Canine Kidney (MDCK) cell line. Thus, 3'-SL was further studied for in vivo study against H9N2 virus in pathogen free chicken experiment models. In vivo study exhibited improved clinical symptoms on H9N2 infected chickens when treated with 3'-SL. Moreover, treating chickens with 3'-SL resulted in complete elimination of H9N2 viruses within 24 h of virus infection (0.8 HAU of H9N2). Indirect ELISA assay confirmed complete wash-out of H9N2 viruses from the colon after neutralization by 3'-SL without entering the blood stream. These in vivo results open up possible applications of 3'-SL for the prevention of AI virus infections in birds by a simple cleansing mechanism.

Physicochemical properties of macrogol ointment and emulsion ointment blend developed for regulation of water absorption.

PubMed

Noda, Yasuhiro; Watanabe, Kazuya; Sanagawa, Akimasa; Sobajima, Yu; Fujii, Satoshi

2011-10-31

Pressure ulcers can form with excess pressure and shearing stress on skin tissue. Because pressure ulcer is often accompanies by exudates, selection of appropriate topical emulsion ointment is difficult. Blended ointments consisting of emulsion base and water-soluble base are clinically used for adjustment of wound moist environment. Because regulating the amount of wound exudates can enhance treatment efficacy, two new blended ointments were developed. LY-SL blended ointment consisted of lysozyme hydrochloride water-in-oil (w/o) emulsion (LY-cream) and sulfadiazine macrogol (polyethylene glycol) ointment (SL-pasta). TR-SL blended ointment consisted of tretinoin tocoferil oil-in-water (o/w) emulsion (TR-cream) and SL-pasta (TR-SL). LY-SL and TR-SL were applied to Franz diffusion cell with cellulose membranes for the evaluation of water absorption characteristics at 32 °C. Water absorption rate constants (mg/cm(2)/min(0.5)) were 12.5, 16.3 and 34.6 for LY-cream, TR-cream and SL-pasta, respectively. Water absorption rate constants for LY-SL and TR-SL (SL-pasta 70%) exhibited intermediate values of 21.2 and 27.2, as compared to each ointment alone, respectively. Because amount of water absorbed was linearly related to square root of time, it was suggested that water-absorbable macrogol was surrounded by oily ingredients forming matrix structure. This diffusion-limited structure may regulate water absorption capacity. This is the first report of physicochemical properties of macrogol ointment and emulsion ointment blend developed for regulation of water absorption. The blended ointment can properly regulate amount of exudates in wounds and may be useful for treatment of pressure ulcers. Copyright © 2011 Elsevier B.V. All rights reserved.

Continuous sea-level reconstructions beyond the Pleistocene: improving the Mediterranean sea-level method

NASA Astrophysics Data System (ADS)

Grant, K.; Rohling, E. J.; Amies, J.

2017-12-01

Sea-level (SL) reconstructions over glacial-interglacial timeframes are critical for understanding the equilibrium response of ice sheets to sustained warming. In particular, continuous and high-resolution SL records are essential for accurately quantifying `natural' rates of SL rise. Global SL changes are well-constrained since the last glacial maximum ( 20,000 years ago, ky) by radiometrically-dated corals and paleoshoreline data, and fairly well-constrained over the last glacial cycle ( 150 ky). Prior to that, however, studies of ice-volume:SL relationships tend to rely on benthic δ18O, as geomorphological evidence is far more sparse and less reliably dated. An alternative SL reconstruction method (the `marginal basin' approach) was developed for the Red Sea over 500 ky, and recently attempted for the Mediterranean over 5 My (Rohling et al., 2014, Nature). This method exploits the strong sensitivity of seawater δ18O in these basins to SL changes in the relatively narrow and shallow straits which connect the basins with the open ocean. However, the initial Mediterranean SL method did not resolve sea-level highstands during Northern Hemisphere insolation maxima, when African monsoon run-off - strongly depleted in δ18O - reached the Mediterranean. Here, we present improvements to the `marginal basin' sea-level reconstruction method. These include a new `Med-Red SL stack', which combines new probabilistic Mediterranean and Red Sea sea-level stacks spanning the last 500 ky. We also show how a box model-data comparison of water-column δ18O changes over a monsoon interval allows us to quantify the monsoon versus SL δ18O imprint on Mediterranean foraminiferal carbonate δ18O records. This paves the way for a more accurate and fully continuous SL reconstruction extending back through the Pliocene.

Patient Background Factors Affecting the Therapeutic Outcomes in Response to Eszopiclone in Adult Patients with Chronic Insomnia: A Post Hoc Analysis of a Double-Blind Phase III Study in Japan

PubMed Central

Inoue, Yuichi; Kamijo, Atsushi; Nagai, Reiko

2015-01-01

Study Objective: To identify whether baseline demographic factors or subjective sleep variables are associated with the outcomes following treatment with eszopiclone using data from a recent randomized controlled trial of 78 Japanese subjects with insomnia who were treated with 2 mg eszopiclone per day. Methods: We performed a post hoc analysis of factors including sleep latency (SL), wake time after sleep onset (WASO) (both assessed via sleep diaries), and several demographic variables. Subjects with a SL or WASO > 30 min at baseline and with evaluable SL/WASO data at Week 4 were included in SL and WASO remitter analyses, respectively; those with a SL or WASO ≤ 30 min at Week 4 were defined as SL or WASO remitters, respectively. Threshold baseline SL and WASO values for identification of remitters were determined. Results: No relationships between subjectively assessed therapeutic outcomes and demographic factors were identified. Patients with shorter SL and lower WASO values at baseline showed better outcomes following treatment with eszopiclone in terms of SL and WASO changes, respectively. Baseline SL of 75 min and baseline WASO of 80 min were selected as arbitrary cutoff values for determination of SL and WASO remitters/non-remitters, respectively. Conclusions: These findings may help clinicians to predict their patients' outcomes in response to standard doses of eszopiclone in clinical practice. Citation: Inoue Y, Kamijo A, Nagai R. Patient background factors affecting the therapeutic outcomes in response to eszopiclone in adult patients with chronic insomnia: a post hoc analysis of a double-blind phase III study in Japan. J Clin Sleep Med 2015;11(10):1171–1178. PMID:26094929

Prophylaxis and therapy of mouse mammary carcinomas with doxorubicin and vincristine encapsulated in sterically stabilised liposomes.

PubMed

Vaage, J; Donovan, D; Loftus, T; Uster, P; Working, P

1995-01-01

This study tested the prophylactic efficacies of doxorubicin hydrochloride and vincristine sulphate, encapsulated in sterically stabilised long circulating liposomes, against the spontaneous development of mammary carcinomas in C3H/He mice. Monthly prophylactic intravenous (i.v.) injections of 6 mg/kg doses of liposome-encapsulated doxorubicin (DOX-SL) or 1 mg/kg doses of liposome-encapsulated vincristine (VIN-SL) were begun when retired breeding mice were 26 weeks old. Mice that developed a mammary carcinoma while on the monthly prophylactic protocols were then given weekly i.v. injections of 6 mg/kg DOX-SL or 1 mg/kg VIN-SL to test the therapeutic efficacies of the drugs, and to determine whether the tumours were susceptible or resistant to therapy. The monthly prophylactic injections reduced the incidence of first mammary carcinomas from 87/88 (99%) in untreated mice to 24/42 (57%) in DOX-SL-treated mice and to 26/32 (81%) in VIN-SL-treated mice. Of the mice that developed a mammary tumour while on the prophylactic protocols, 12 of 30 mice were cured by the weekly therapeutic use of DOX-SL, and the growth of 18 tumours was inhibited. The weekly therapeutic use of VIN-SL cured 3 of 8 mice, and inhibited the growth of five tumours. Weekly DOX-SL therapy cured 7 of 22 previously untreated mice. The mean survival of tumour-bearing mice was extended from 24 days in untreated mice to 87 days in DOX-SL-treated mice, which had not received prophylactic treatment. Metastases were found in 29 of 54 untreated mice, and in 3 of 72 mice treated with DOX-SL and VIN-SL. Toxic side effects were limited to a transient weight loss during the weekly treatments. Drug resistance as a result of treatments was not observed.

SlTPR1, a tomato tetratricopeptide repeat protein, interacts with the ethylene receptors NR and LeETR1, modulating ethylene and auxin responses and development

PubMed Central

Lin, Zhefeng; Arciga-Reyes, Luis; Zhong, Silin; Alexander, Lucy; Hackett, Rachel; Wilson, Ian; Grierson, Don

2008-01-01

The gaseous hormone ethylene is perceived by a family of ethylene receptors which interact with the Raf-like kinase CTR1. SlTPR1 encodes a novel TPR (tetratricopeptide repeat) protein from tomato that interacts with the ethylene receptors NR and LeETR1 in yeast two-hybrid and in vitro protein interaction assays. SlTPR1 protein with a GFP fluorescent tag was localized in the plasmalemma and nuclear membrane in Arabidopsis, and SlTPR1-CFP and NR-YFP fusion proteins were co-localized in the plasmalemma and nuclear membrane following co-bombardment of onion cells. Overexpression of SlTPR1 in tomato resulted in ethylene-related pleiotropic effects including reduced stature, delayed and reduced production of inflorescences, abnormal and infertile flowers with degenerate styles and pollen, epinasty, reduced apical dominance, inhibition of abscission, altered leaf morphology, and parthenocarpic fruit. Similar phenotypes were seen in Arabidopsis overexpressing SlTPR1. SlTPR1 overexpression did not increase ethylene production but caused enhanced accumulation of mRNA from the ethylene responsive gene ChitB and the auxin-responsive gene SlSAUR1-like, and reduced expression of the auxin early responsive gene LeIAA9, which is known to be inhibited by ethylene and to be associated with parthenocarpy. Cuttings from the SlTPR1-overexpressors produced fewer adventitious roots and were less responsive to indole butyric acid. It is suggested that SlTPR1 overexpression enhances a subset of ethylene and auxin responses by interacting with specific ethylene receptors. SlTPR1 shares features with human TTC1, which interacts with heterotrimeric G-proteins and Ras, and competes with Raf-1 for Ras binding. Models for SlTPR1 action are proposed involving modulation of ethylene signalling or receptor levels. PMID:19036844

Reproducibility and Agreement Between 2 Spectral Domain Optical Coherence Tomography Devices for Anterior Chamber Angle Measurements

PubMed Central

Marion, Kenneth M.; Maram, Jyotsna; Pan, Xiaojing; Dastiridou, Anna; Zhang, ZhouYuan; Ho, Alex; Francis, Brian A.; Sadda, Srinivas R.

2015-01-01

Purpose: To compare anterior chamber angle parameters based on the location of Schwalbe line (SL) from 2 spectral domain optical coherence tomography (SD-OCT) instruments and to measure their reproducibility. Methods: Forty-two eyes from 21 normal, healthy participants underwent imaging of the inferior irido-corneal angle with the Spectralis and Cirrus SD-OCT under tightly controlled low-light conditions. SL-angle opening distance (SL-AOD) and SL-trabecular iris space area (SL-TISA) were measured by masked, certified graders at the Doheny Imaging Reading Center using customized grading software. Interinstrument and intrainstrument, as well as interobserver and intraobserver reproducibility of SL-AOD and SL-TISA measurements were evaluated by intraclass correlation coefficients (ICCs) and Bland-Altman plots with limits of agreement (LoA). Results: The mean SL-AOD was 0.662±0.191 mm in Spectralis and 0.677±0.213 mm in Cirrus. The mean SL-TISA was 0.250±0.073 mm2 in Spectralis and 0.256±0.082 mm2 in Cirrus. The agreement for intrainstrument (ICCs>0.979), intragrader (ICCs>0.992), and intergrader (ICCs>0.929) was excellent. Excellent agreement between the 2 devices was also documented with a mean difference of −0.016 (LoA −0.125 to 0.092) mm for SL-AOD and −0.007 (LoA −0.056 to 0.043) mm2 in SL-TISA. Conclusions: Both SD-OCTs provided comparable measurements and permitted calculation of SL-based angle metrics. There was excellent interinstrument and intrainstrument and intraobserver and interobserver reproducibility for Spectralis and Cirrus SD-OCTs, suggesting true interchangeability between SD-OCT devices. This has the potential to lead to development of standardized grading assessments and quantification of angle parameters that would be valid across various SD-OCT devices. PMID:26200742

Submandibular and sublingual glands involvement in advanced acquired immunodeficiency syndrome (AIDS): an autopsy-based study.

PubMed

León, Jorge E; Mauad, Thais; Saldiva, Paulo H N; Almeida, Oslei P; Vargas, Pablo A

2009-08-01

To assess the histopathological, immunohistochemical (IHC), and in situ hybridization (ISH) features found in the submandibular (SM) and sublingual (SL) glands of 105 acquired immunodeficiency syndrome (AIDS) patients at autopsy. Gender, age, CD4 cell level, and clinical histories were obtained from clinical charts (SM: n = 103; SL: n = 92). Histologic analysis of hematoxylin and eosin, Gomori-Grocott, and Ziehl-Neelsen stained tissues, IHC to detect infectious agents and characterize inflammatory cells in sialadenitis, and ISH for EBER-1/2 were performed. The mean age of the patients and CD4 cell count were 36 years and 76 cells/microL, respectively. Fifty-eight cases (SM: n = 51 [49%]; SL: n = 54 [59%]) were considered to be microscopically normal. The most common infectious conditions were mycobacteriosis (SM: n = 11 [10%]; SL: n = 7 [7%]), followed by cytomegalovirus (CMV) (SM: n = 14 [13%]; SL: n = 2 [2%]), and cryptococcosis (SM: n = 3 [3%]; SL: n = 4 [4%]). Human immunodeficiency virus (HIV) p24 (SM: n = 2 [2%]; SL: n = 1 [1%]) and EBER-1/2 (SM: n = 9 [39%]; SL: n = 4 [20%]) were seen only in macrophages and lymphocytes, respectively. The most prevalent cells seen in chronic nonspecific sialadenitis (SM: n = 25; SL: n = 25) were CD8+ T lymphocytes, whereas CD68+ macrophages were predominant in the mycobacteriosis-associated granulomatous and nonspecific diffuse macrophagic sialadenitis. Concomitant infections occurred in 5 cases (SM: n = 4; SL: n = 1) and non-Hodgkin lymphoma in 1 case. Infectious diseases and chronic nonspecific sialadenitis were the main alterations found in the SM and SL glands. These alterations were greater in the SM than in the SL glands. CD8+ T lymphocytes and CD68+ macrophages might be relevant to the pathogenesis of the sialadenitis. Clinicians should consider these diseases when assessing the major salivary glands in advanced AIDS patients and follow biosafety procedures to avoid contamination by HIV, CMV, mycobacteriosis, and cryptococcosis.

Studies of reaction variables for lipase-catalyzed production of alpha-linolenic acid enriched structured lipid and oxidative stability with antioxidants.

PubMed

Mitra, Kanika; Shin, Jung-Ah; Lee, Jeung-Hee; Kim, Seong-Ai; Hong, Soon-Taek; Sung, Chang-Keun; Xue, Cheng Lian; Lee, Ki-Teak

2012-01-01

Alpha-linolenic acid (ALA) enriched structured lipid (SL) was produced by lipase-catalyzed interesterification from perilla oil (PO) and corn oil (CO). The effects of different reaction conditions (substrate molar ratio [PO/CO 1:1 to 1:3], reaction time [0 to 24 h], and reaction temperature [55 to 65 °C]) were studied. Lipozyme RM IM from Rhizomucor miehei was used as biocatalyst. We obtained 32.39% of ALA in SL obtained under the optimized conditions (molar ratio-1:1 [PO:CO], temperature-60 °C, reaction time-15 h). In SL, the major triacylglycerol (TAG) species (linolenoyl-linolenoyl-linolenoyl glycerol [LnLnLn], linolenoyl-linolenoyl-linoleoyl glycerol [LnLnL]) mainly from PO and linoleoyl-linoleoyl-oleoyl glycerol (LLO), linoleoyl-oleoyl-oleoyl glycerol (LOO), palmitoyl-linoleoyl-oleoyl glycerol (PLO) from CO decreased while linolenoyl-linolenoyl-oleoyl glycerol (LnLnO) (18.41%), trilinolein (LLL) (9.06%), LLO (16.66%), palmitoyl-linoleoyl-linoleoyl glycerol (PLL) (9.69%) were increased compared to that of physical blend. Total tocopherol content (28.01 mg/100 g), saponification value (SV) (192.2), and iodine value (IV) (161.9) were obtained. Furthermore, oxidative stability of the SL was also investigated by addition of 3 different antioxidants (each 200 ppm of rosemary extract [SL-ROS], BHT [SL-BHT], catechin [SL-CAT]) was added into SL and stored in 60 °C oven for 30 d. 2-Thiobabituric acid-reactive substances (TBARS) value was 0.16 mg/kg in SL-CAT and 0.18 mg/kg in SL-ROS as compared with 0.22 mg/kg in control (SL) after oxidation. The lowest peroxide value (POV, 200.9 meq/kg) and longest induction time (29.88 h) was also observed in SL-CAT. © 2011 Institute of Food Technologists®

Production of trans-free margarine with stearidonic acid soybean and high-stearate soybean oils-based structured lipid.

PubMed

Pande, Garima; Akoh, Casimir C; Shewfelt, Robert L

2012-11-01

Omega-3 fatty acids (n-3 FAs) have been positively associated with prevention and treatment of chronic diseases. Intake of high amounts of trans fatty acids (TFAs) is correlated with increased risk of coronary heart disease, inflammation, and cancer. Structured lipid (SL) was synthesized using stearidonic acid (SDA) soybean oil and high-stearate soybean oil catalyzed by Lipozyme(®) TLIM lipase. The SL was compared to extracted fat (EF) from a commercial brand for FA profile, sn-2 positional FAs, triacylglycerol (TAG) profile, polymorphism, thermal behavior, oxidative stability, and solid fat content (SFC). Both SL and EF had similar saturated FA (about 31 mol%) and unsaturated FA (about 68 mol%), but SL had a much lower n-6/n-3 ratio (1.1) than EF (5.8). SL had 10.5 mol% SDA. After short-path distillation, a loss of 53.9% was observed in the total tocopherol content of SL. The tocopherols were lost as free tocopherols. SL and EF had similar melting profile, β' polymorph, and oxidative stability. Margarine was formulated using SL (SLM) and EF (RCM, reformulated commercial margarine). No sensory difference was observed between the 2 margarines. The SL synthesized in this study contained no TFA and possessed desirable polymorphism, thermal properties, and SFC for formulation of soft margarine. The margarine produced with this SL was trans-free and SDA-enriched. The current research increases the food applications of stearidonic acid (SDA) soybean oil. trans-Free SDA containing SL was synthesized with desirable polymorph, thermal properties, and SFC for formulation of soft margarine. The margarine produced with this SL had no trans fat and had a low n-6/n-3 ratio. This may help in reducing trans fat intake in our diet while increasing n-3 FA intake. © 2012 Institute of Food Technologists®

Tomato Sl3-MMP, a member of the Matrix metalloproteinase family, is required for disease resistance against Botrytis cinerea and Pseudomonas syringae pv. tomato DC3000.

PubMed

Li, Dayong; Zhang, Huijuan; Song, Qiuming; Wang, Lu; Liu, Shixia; Hong, Yongbo; Huang, Lei; Song, Fengming

2015-06-14

Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases. MMPs have been characterized in detail in mammals and shown to play key roles in many physiological and pathological processes. Although MMPs in some plant species have been identified, the function of MMPs in biotic stress responses remains elusive. A total of five MMP genes were identified in tomato genome. qRT-PCR analysis revealed that expression of Sl-MMP genes was induced with distinct patterns by infection of Botrytis cinerea and Pseudomonas syringae pv. tomato (Pst) DC3000 and by treatment with defense-related hormones such as salicylic acid, jasmonic acid and ethylene precursor 1-amino cyclopropane-1-carboxylic acid. Virus-induced gene silencing (VIGS)-based knockdown of individual Sl-MMPs and disease assays indicated that silencing of Sl3-MMP resulted in reduced resistance to B. cinerea and Pst DC3000, whereas silencing of other four Sl-MMPs did not affect the disease resistance against these two pathogens. The Sl3-MMP-silenced tomato plants responded with increased accumulation of reactive oxygen species and alerted expression of defense genes after infection of B. cinerea. Transient expression of Sl3-MMP in leaves of Nicotiana benthamiana led to an enhanced resistance to B. cinerea and upregulated expression of defense-related genes. Biochemical assays revealed that the recombinant mature Sl3-MMP protein had proteolytic activities in vitro with distinct preferences for specificity of cleavage sites. The Sl3-MMP protein was targeted onto the plasma membrane of plant cells when transiently expressed in onion epidermal cells. VIGS-based knockdown of Sl3-MMP expression in tomato and gain-of-function transient expression of Sl3-MMP in N. benthamiana demonstrate that Sl3-MMP functions as a positive regulator of defense response against B. cinerea and Pst DC3000.

Characterization of growth inhibition of oral bacteria by sophorolipid using a microplate-format assay.

PubMed

Solaiman, Daniel K Y; Ashby, Richard D; Uknalis, Joseph

2017-05-01

Sophorolipid (SL) is a class of glycolipid biosurfactant produced by yeast and has potent antimicrobial activity against many microorganisms. In this paper, a microplate-based method was developed to characterize the growth inhibition by SL on five representative species of caries-causing oral bacteria. Bacterial growth on microplate in the absence and presence of varying concentrations of SL was continuously monitored by recording the absorbance at 600nm of the cultures using a microplate reader. The results showed that SL completely inhibited the growth of the Lactobacilli at ≥1mg/ml and the Streptococci at much lower concentrations of ≥50μg/ml. More importantly, we further defined the mechanism of antimicrobial activity of SL by analyzing the pattern of the cell growth curves. SL at sublethal concentrations (<1mg/ml) is bactericidal towards the Lactobacilli; it lengthens the apparent cell-doubling time (T d ) and decreases the final cell density (as indicated by A 600nm ) in a concentration-dependent manner. Against the oral Streptococci, on the other hand, SL at sublethal concentrations (<50μg/ml) is bacteriostatic; it delays the onset of cell growth in a concentration-dependent fashion, but once the cell growth is commenced there is no noticeable adverse effect on T d and the final A 600nm . Scanning electron microscopic (SEM) study of L. acidophilus grown in sublethal concentration of SL reveals extensive structural damage to the cells. S. mutans grown in sublethal level of SL did not show morphological damage to the cells, but numerous protruding structures could be seen on the cell surface. At the respective lethal levels of SL, L. acidophilus cells were lysed (at 1mg/ml SL) and the cell surface structure of S. mutans (at 130μg/ml SL) was extensively deformed. In summary, this paper presents the first report on a detailed analysis of the effects of SL on Lactobacilli and Streptococci important to oral health and hygiene. Published by Elsevier B.V.

A developmentally regulated lipocalin-like gene is overexpressed in Tomato yellow leaf curl virus-resistant tomato plants upon virus inoculation, and its silencing abolishes resistance.

PubMed

Sade, Dagan; Eybishtz, Assaf; Gorovits, Rena; Sobol, Iris; Czosnek, Henryk

2012-10-01

To discover genes involved in tomato resistance to Tomato yellow leaf curl virus (TYLCV), we previously compared cDNA libraries from susceptible (S) and resistant (R) tomato lines. Among the genes preferentially expressed in R plants and upregulated by TYLCV infection was a gene encoding a lipocalin-like protein. This gene was termed Solanum lycopersicum virus resistant/susceptible lipocalin (SlVRSLip). The SlVRSLip structural gene sequence of R and S plants was identical. SlVRSLip was expressed in leaves during a 15-day window starting about 40 days after sowing (20 days after planting). SlVRSLip was upregulated by Bemisia tabaci (the TYLCV vector) feeding on R plant leaves, and even more strongly upregulated following whitefly-mediated TYLCV inoculation. Silencing of SlVRSLip in R plants led to the collapse of resistance upon TYLCV inoculation and to a necrotic response along the stem and petioles accompanied by ROS production. Contrary to previously identified tomato lipocalin gene DQ222981, SlVRSLip was not regulated by cold, nor was it regulated by heat or salt. The expression of SlVRSLip was inhibited in R plants in which the hexose transporter gene LeHT1 was silenced. In contrast, the expression of LeHT1 was not inhibited in SlVRSLip-silenced R plants. Hence, in the hierarchy of the gene network conferring TYLCV resistance, SlVRSLip is downstream of LeHT1. Silencing of another gene involved in resistance, a Permease-I like protein, did not affect the expression of SlVRSLip and LeHT1; expression of the Permease was not affected by silencing SlVRSLip or LeHT1, suggesting that it does not belong to the same network. The triple co-silencing of SlVRSLip, LeHT1 and Permease provoked an immediate cessation of growth of R plants upon infection and the accumulation of large amounts of virus. SlVRSLip is the first lipocalin-like gene shown to be involved in resistance to a plant virus.

Equatorial and Apical Solvent Shells of the UO₂²⁺ Ion.

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

Nichols, Pat; Bylaska, Eric J.; Schenter, Gregory K.

2008-03-08

First principles molecular dynamics simulations of the hydration shells surrounding UO₂²⁺ ions are reported for temperatures near 300 K. Most of the simulations were done with 64 solvating water molecules (22 ps). Simulations with 122 water molecules (9 ps) were also carried out. The hydration structure predicted from the simulations was found to agree very well known results from X-ray data. The average U=O bond length was found to be 1.77Å . The first hydration shell contained five trigonally coordinated water molecules that were equatorially oriented about the O-U-O axis with the hydrogen atoms oriented away from the uranium atom.more » The five waters in the first shell were located at an average distance of 2.44Å (2.46Å - 122 water simulation). The second hydration shell was composed of distinct equatorial and apical regions resulting in a peak in the U-O radial distribution function at 4.59Å. The equatorial second shell contained 10 water molecules hydrogen-bonded to the five first shell molecules. Above and below the UO₂²⁺ ion, the water molecules were found to be significantly less structured. In these apical regions, water molecules were found to sporadically hydrogen bond to the oxygen atoms of the UO₂²⁺; oriented in such way as to have their protons pointed towards the cation. While the number of apical waters varied greatly, an average of 5-6 waters was found in this region. Many water transfers into and out of the equatorial and apical second solvation shells were observed to occur on a picosecond (ps) time scale via dissociative mechanisms. Beyond these shells, the bonding pattern substantially returned to the tetrahedral structure of bulk water.« less

The geometry of protein hydration

NASA Astrophysics Data System (ADS)

Persson, Filip; Söderhjelm, Pär; Halle, Bertil

2018-06-01

Based on molecular dynamics simulations of four globular proteins in dilute aqueous solution, with three different water models, we examine several, essentially geometrical, aspects of the protein-water interface that remain controversial or incompletely understood. First, we compare different hydration shell definitions, based on spatial or topological proximity criteria. We find that the best method for constructing monolayer shells with nearly complete coverage is to use a 5 Å water-carbon cutoff and a 4 Å water-water cutoff. Using this method, we determine a mean interfacial water area of 11.1 Å2 which appears to be a universal property of the protein-water interface. We then analyze the local coordination and packing density of water molecules in the hydration shells and in subsets of the first shell. The mean polar water coordination number in the first shell remains within 1% of the bulk-water value, and it is 5% lower in the nonpolar part of the first shell. The local packing density is obtained from additively weighted Voronoi tessellation, arguably the most physically realistic method for allocating space between protein and water. We find that water in all parts of the first hydration shell, including the nonpolar part, is more densely packed than in the bulk, with a shell-averaged density excess of 6% for all four proteins. We suggest reasons why this value differs from previous experimental and computational results, emphasizing the importance of a realistic placement of the protein-water dividing surface and the distinction between spatial correlation and packing density. The protein-induced perturbation of water coordination and packing density is found to be short-ranged, with an exponential decay "length" of 0.6 shells. We also compute the protein partial volume, analyze its decomposition, and argue against the relevance of electrostriction.

Development of a Prototype Nickel Optic for the Constellation-X Hard-X-Ray Telescope

NASA Technical Reports Server (NTRS)

Basso, S.; Bruni, R. J.; Citerio, O.; Engelhaupt, D.; Ghigo, M.; Gorenstien, P.; Mazzoleni, F.; ODell, S. L.; Pareschi, G.; Ramsey, B. D.

2003-01-01

The Constellation-X mission, planned for launch in 2011, will feature an array of hard-x ray telescopes with a total collecting area goal of 1500 square centimeters at 40 keV. Various technologies are currently being investigated for the optics of these telescopes including multilayer-coated Eletroformed-Nickel-Replicated (ENR) shells. The attraction of the ENR process is that the resulting full-shell optics are inherently stable and offer the promise of good angular resolution and enhanced instrument sensitivity. The challenge for this process is to meet a relatively tight weight budget with a relatively dense material (rho nickel = 9 grams per cubic centimeters.) To demonstrate the viability of the ENR process we are fabricating a prototype HXT mirror module to be tested against a competing segmented-glass-shell optic. The ENR prototype will consist of 5 shells of diameters from 150 mm to 280 mm and of 426 mm total length. To meet the stringent weight budget for Con-X, the shells will be only 150 micron thick. The innermost of these will be coated with Iridium, while the remainder will be coated with graded-density multilayers. Mandrels for these shells are currently under fabrication (Jan 03), with the first shells scheduled for production in February 03. A tentative date of late Summer has been set for prototype testing. Issues currently being addressed are the control of stresses in the multiplayer coating and ways of mitigating their effects on the figure of the necessarily thin shells. Also, the fabrication, handling and mounting of these shells without inducing permanent figure distortions. A full status report on the prototype optic will be presented along with test results as available.

Compressibility of the protein-water interface

NASA Astrophysics Data System (ADS)

Persson, Filip; Halle, Bertil

2018-06-01

The compressibility of a protein relates to its stability, flexibility, and hydrophobic interactions, but the measurement, interpretation, and computation of this important thermodynamic parameter present technical and conceptual challenges. Here, we present a theoretical analysis of protein compressibility and apply it to molecular dynamics simulations of four globular proteins. Using additively weighted Voronoi tessellation, we decompose the solution compressibility into contributions from the protein and its hydration shells. We find that positively cross-correlated protein-water volume fluctuations account for more than half of the protein compressibility that governs the protein's pressure response, while the self correlations correspond to small (˜0.7%) fluctuations of the protein volume. The self compressibility is nearly the same as for ice, whereas the total protein compressibility, including cross correlations, is ˜45% of the bulk-water value. Taking the inhomogeneous solvent density into account, we decompose the experimentally accessible protein partial compressibility into intrinsic, hydration, and molecular exchange contributions and show how they can be computed with good statistical accuracy despite the dominant bulk-water contribution. The exchange contribution describes how the protein solution responds to an applied pressure by redistributing water molecules from lower to higher density; it is negligibly small for native proteins, but potentially important for non-native states. Because the hydration shell is an open system, the conventional closed-system compressibility definitions yield a pseudo-compressibility. We define an intrinsic shell compressibility, unaffected by occupation number fluctuations, and show that it approaches the bulk-water value exponentially with a decay "length" of one shell, less than the bulk-water compressibility correlation length. In the first hydration shell, the intrinsic compressibility is 25%-30% lower than in bulk water, whereas its self part is 15%-20% lower. These large reductions are caused mainly by the proximity to the more rigid protein and are not a consequence of the perturbed water structure.

Compressibility of the protein-water interface.

PubMed

Persson, Filip; Halle, Bertil

2018-06-07

The compressibility of a protein relates to its stability, flexibility, and hydrophobic interactions, but the measurement, interpretation, and computation of this important thermodynamic parameter present technical and conceptual challenges. Here, we present a theoretical analysis of protein compressibility and apply it to molecular dynamics simulations of four globular proteins. Using additively weighted Voronoi tessellation, we decompose the solution compressibility into contributions from the protein and its hydration shells. We find that positively cross-correlated protein-water volume fluctuations account for more than half of the protein compressibility that governs the protein's pressure response, while the self correlations correspond to small (∼0.7%) fluctuations of the protein volume. The self compressibility is nearly the same as for ice, whereas the total protein compressibility, including cross correlations, is ∼45% of the bulk-water value. Taking the inhomogeneous solvent density into account, we decompose the experimentally accessible protein partial compressibility into intrinsic, hydration, and molecular exchange contributions and show how they can be computed with good statistical accuracy despite the dominant bulk-water contribution. The exchange contribution describes how the protein solution responds to an applied pressure by redistributing water molecules from lower to higher density; it is negligibly small for native proteins, but potentially important for non-native states. Because the hydration shell is an open system, the conventional closed-system compressibility definitions yield a pseudo-compressibility. We define an intrinsic shell compressibility, unaffected by occupation number fluctuations, and show that it approaches the bulk-water value exponentially with a decay "length" of one shell, less than the bulk-water compressibility correlation length. In the first hydration shell, the intrinsic compressibility is 25%-30% lower than in bulk water, whereas its self part is 15%-20% lower. These large reductions are caused mainly by the proximity to the more rigid protein and are not a consequence of the perturbed water structure.

Studies on Freezing of Shell-Fish-I

NASA Astrophysics Data System (ADS)

Song, Dae Jin; Konagaya, Shiro; Tanaka, Takeo

Ark shell, Anadara broughtonii(Shrenk), are commonly eaten raw or under-done in Korea, Japan, and East Asian countries. Along with a recent remarkable development of culture fisheries, Ark shell has become one of the commercially important shell-fish species. Transportation and storage of large quantities of shell-fish is becoming increasingly important. This work was begun with this background to make clear the effects of temperature and length of storage time on the quality of frozen stored ark shell. Results are as follows : (1) There was little chang in amounts of free and expressible drip from ark shell flesh frozen stored at -40°CdegC for 6 months. Water holding capacity of the same meat was almost constant over 6 months storage. However, a mounts of both drip increased markedly after 2 months storage at -10°C. (2) Protein extractibility of ark shell flesh tended to decrease gradually from the begining when stored at -10°C, while at -20°C, the protein extractibility was stable for 3 months before decreasing gradually. However at -40°C, the protein extractibility was stable for 6 months. It was found that paramyosin was very stable even when the ark shell was frozen stored at -10°C. (3) It was observed that ark shell flesh became tough when frozen. The toughness of ark shell flesh as measured by an instrument increased with frozen storage time and increased temperature. (4) In the smooth muscle, it was histologically observed that initial small ice crystals formed between muscle bundles grew larger during frozen storage. It was found that the higher the storage temperature, the bigger the ice crystals formed. Aggregation of some muscle fiber and empty spaces between muscle bundles were observd after thawed muscles frozen stored at relatively high temperature such as -10°C.

Food Supply and Seawater pCO2 Impact Calcification and Internal Shell Dissolution in the Blue Mussel Mytilus edulis

PubMed Central

Melzner, Frank; Stange, Paul; Trübenbach, Katja; Thomsen, Jörn; Casties, Isabel; Panknin, Ulrike; Gorb, Stanislav N.; Gutowska, Magdalena A.

2011-01-01

Progressive ocean acidification due to anthropogenic CO2 emissions will alter marine ecosytem processes. Calcifying organisms might be particularly vulnerable to these alterations in the speciation of the marine carbonate system. While previous research efforts have mainly focused on external dissolution of shells in seawater under saturated with respect to calcium carbonate, the internal shell interface might be more vulnerable to acidification. In the case of the blue mussel Mytilus edulis, high body fluid pCO2 causes low pH and low carbonate concentrations in the extrapallial fluid, which is in direct contact with the inner shell surface. In order to test whether elevated seawater pCO2 impacts calcification and inner shell surface integrity we exposed Baltic M. edulis to four different seawater pCO2 (39, 142, 240, 405 Pa) and two food algae (310–350 cells mL−1 vs. 1600–2000 cells mL−1) concentrations for a period of seven weeks during winter (5°C). We found that low food algae concentrations and high pCO2 values each significantly decreased shell length growth. Internal shell surface corrosion of nacreous ( = aragonite) layers was documented via stereomicroscopy and SEM at the two highest pCO2 treatments in the high food group, while it was found in all treatments in the low food group. Both factors, food and pCO2, significantly influenced the magnitude of inner shell surface dissolution. Our findings illustrate for the first time that integrity of inner shell surfaces is tightly coupled to the animals' energy budget under conditions of CO2 stress. It is likely that under food limited conditions, energy is allocated to more vital processes (e.g. somatic mass maintenance) instead of shell conservation. It is evident from our results that mussels exert significant biological control over the structural integrity of their inner shell surfaces. PMID:21949698

Food supply and seawater pCO2 impact calcification and internal shell dissolution in the blue mussel Mytilus edulis.

PubMed

Melzner, Frank; Stange, Paul; Trübenbach, Katja; Thomsen, Jörn; Casties, Isabel; Panknin, Ulrike; Gorb, Stanislav N; Gutowska, Magdalena A

2011-01-01

Progressive ocean acidification due to anthropogenic CO(2) emissions will alter marine ecosystem processes. Calcifying organisms might be particularly vulnerable to these alterations in the speciation of the marine carbonate system. While previous research efforts have mainly focused on external dissolution of shells in seawater under saturated with respect to calcium carbonate, the internal shell interface might be more vulnerable to acidification. In the case of the blue mussel Mytilus edulis, high body fluid pCO(2) causes low pH and low carbonate concentrations in the extrapallial fluid, which is in direct contact with the inner shell surface. In order to test whether elevated seawater pCO(2) impacts calcification and inner shell surface integrity we exposed Baltic M. edulis to four different seawater pCO(2) (39, 142, 240, 405 Pa) and two food algae (310-350 cells mL(-1) vs. 1600-2000 cells mL(-1)) concentrations for a period of seven weeks during winter (5°C). We found that low food algae concentrations and high pCO(2) values each significantly decreased shell length growth. Internal shell surface corrosion of nacreous ( = aragonite) layers was documented via stereomicroscopy and SEM at the two highest pCO(2) treatments in the high food group, while it was found in all treatments in the low food group. Both factors, food and pCO(2), significantly influenced the magnitude of inner shell surface dissolution. Our findings illustrate for the first time that integrity of inner shell surfaces is tightly coupled to the animals' energy budget under conditions of CO(2) stress. It is likely that under food limited conditions, energy is allocated to more vital processes (e.g. somatic mass maintenance) instead of shell conservation. It is evident from our results that mussels exert significant biological control over the structural integrity of their inner shell surfaces.

The Universal R-Matrix for the Jordanian Deformation of sl(2), and the Contracted Forms of so(4)

NASA Astrophysics Data System (ADS)

Shariati, A.; Aghamohammadi, A.; Khorrami, M.

We introduce a universal R-matrix for the Jordanian deformation of U(sl(2)). Using Uh(so(4))=Uh(sl(2)) ⊕ U-h(sl(2)), we obtain the universal R-matrix for Uh(so(4)). Applying the graded contractions on the universal R-matrix of Uh(so(4)), we show that there exist three distinct R-matrices for all the contracted algebras. It is shown that Uh(sl(2)), Uh(so(4)), and all of these contracted algebras are triangular.

Orders and dimensions for sl(2) or sl(3) module categories and boundary conformal field theories on a torus

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

Coquereaux, R.; Schieber, G.; Centro Brasileiro de Pesquisas Fisicas

2007-04-15

After giving a short description, in terms of action of categories, of some of the structures associated with sl(2) and sl(3) boundary conformal field theories on a torus, we provide tables of dimensions describing the semisimple and cosemisimple blocks of the corresponding weak bialgebras (quantum groupoids), tables of quantum dimensions and orders, and tables describing induction-restriction. For reasons of size, the sl(3) tables of induction are only given for theories with self-fusion (existence of a monoidal structure)

A Cluster Analytic Examination of Acculturation and Health Status among Asian Americans in the Washington DC Metropolitan Area, United States

PubMed Central

Lee, Sunmin; Chen, Lu; He, Xin; Miller, Matthew J.; Juon, Hee-Soon

2013-01-01

Previous studies reported mixed findings on the relationship between acculturation and health status among Asian Americans due to different types of acculturation measures used or different Asian subgroups involved in various studies. We aim to fill the gap by applying multiple measures of acculturation in a diverse sample of Asian subgroups. A cross sectional study was conducted among Chinese, Korean and Vietnamese Americans in Washington D.C. Metropolitan Area to examine the association between health status and acculturation using multiple measures including the Suinn-Lew Asian Self-Identity Acculturation (SL-ASIA) scale, clusters based on responses to SL-ASIA, language preference, length of stay, age at arrival in the United Sates and self-identity. Three clusters (Asian (31%); Bicultural (47%); and American (22%)) were created by using a two-step hierarchical method and Bayesian Information Criterion values. Across all the measures, more acculturated individuals were significantly more likely to report good health than those who were less acculturated after adjusting for covariates. Specifically, those in the American cluster were 3.8 times (95% Confidence Interval (CI): 2.2, 6.6) more likely and those in the Bicultural cluster were 1.7 times more likely (95% CI: 1.1, 2.4) to report good health as compared to those in the Asian cluster. When the conventional standardized SL-ASIA summary score (range: −1.4 to 1.4) was used, a one point increase was associated with 2.2 times greater odds of reporting good health (95% CI: 1.5, 3.2). However, the interpretation may be challenging due to uncertainty surrounding the meaning of a one point increase in SL-ASIA summary score. Among all the measures used, acculturation clusters better approximated the acculturation process and provided us with a more accurate test of the association in the population. Variables included in this measure were more relevant for our study sample and may have worked together to capture the multifaceted acculturation process. PMID:24034947

Turbulent Flame Propagation Characteristics of High Hydrogen Content Fuels

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

Seitzman, Jerry; Lieuwen, Timothy

2014-09-30

This final report describes the results of an effort to better understand turbulent flame propagation, especially at conditions relevant to gas turbines employing fuels with syngas or hydrogen mixtures. Turbulent flame speeds were measured for a variety of hydrogen/carbon monoxide (H2/CO) and hydrogen/methane (H2/CH4) fuel mixtures with air as the oxidizer. The measurements include global consumption speeds (ST,GC) acquired in a turbulent jet flame at pressures of 1-10 atm and local displacement speeds (ST,LD) acquired in a low-swirl burner at atmospheric pressure. The results verify the importance of fuel composition in determining turbulent flame speeds. For example, different fuel-air mixturesmore » having the same unstretched laminar flame speed (SL,0) but different fuel compositions resulted in significantly different ST,GC for the same turbulence levels (u'). This demonstrates the weakness of turbulent flame speed correlations based simply on u'/SL,0. The results were analyzed using a steady-steady leading points concept to explain the sensitivity of turbulent burning rates to fuel (and oxidizer) composition. Leading point theories suggest that the premixed turbulent flame speed is controlled by the flame front characteristics at the flame brush leading edge, or, in other words, by the flamelets that advance farthest into the unburned mixture (the so-called leading points). For negative Markstein length mixtures, this is assumed to be close to the maximum stretched laminar flame speed (SL,max) for the given fuel-oxidizer mixture. For the ST,GC measurements, the data at a given pressure were well-correlated with an SL,max scaling. However the variation with pressure was not captured, which may be due to non-quasi-steady effects that are not included in the current model. For the ST,LD data, the leading points model again faithfully captured the variation of turbulent flame speed over a wide range of fuel-compositions and turbulence intensities. These results provide evidence that the leading points model can provide useful predictions of turbulent flame speed over a wide range of operating conditions and flow geometries.« less

Topographic Control of Aboveground Carbon Pools Across an Environmental Gradient, Eastern Slope of the Rocky Mountains, Colorado.

NASA Astrophysics Data System (ADS)

Swetnam, T. L.; Brooks, P. D.; Gallo, E. L.; Barnard, H. R.; Harpold, A. A.

2015-12-01

Evaluating at high spatial-resolution the topographical and ecological structures of the critical zone (CZ) are now routine with aerial LiDAR. Here we evaluated the eco-hydrological differences of topographic metrics (the independent variables) versus individual tree and gridded aboveground carbon (AGC) pools (as dependent variables) at multiple length-scales across an elevation modified gradient of precipitation and temperature in the Boulder Creek CZ Observatory Watershed, Colorado USA. We describe the responses in AGC within the context of a three-zone eco-hydrological model, e.g. toe slope and valley bottoms (Zone 1), transitional hillslopes (Zone 2), and upper slopes to ridges (Zone 3). In a GIS we compared three separate zero-order basins: (1) the Betasso Preserve: 1,810-2,024 meters above mean sea level (m aμsl), area = 0.45 km2, n = 17,286 trees; (2) Upper and Lower Gordon Gulch: 2,446-2,737 m aμsl, area = 3.57 km2, n = 178,469 trees; and (3) Como Creek: 2,900m-3,560 m aμsl, area = 6.64 km2, n = 317,274 trees. In each of the three catchments Zone 1 held the greatest mean AGC (μ = 52.88-60.97 Mg C ha-1) and maximum AGC (99% confidence interval (CI, p = 0.01) = 152.95-184.95 Mg C ha-1) relative to Zone 2 (μ = 27.84-44.52 Mg C ha-1, 99% CI = 99.67-122.4 Mg C ha-1) and Zone 3 (μ = 12.63-30.33 Mg C ha-1, 99% CI = 62.16-92.65 Mg C ha-1). Topography with negative general curvatures (i.e. convergent shapes) had greater AGC (μ = 73.7-96.3 Mg C ha-1, 99% CI = 189.0-355.8 Mg C ha-1) than positive general curvatures (i.e. divergent shapes) (μ = 17.4-30.8 Mg C ha-1, 99% CI = 88.2-120.4 Mg C ha-1), but only when evaluated at longer length scales (<10 m). Larger AGC pools are postulated to be related to (1) increased soil depth which provides larger rooting zones and (2) access to groundwater along Zone 1, vs Zones 2 and 3 which have (a) shallower soils and (b) less or zero accessibility to groundwater.

Argentina set for privatization

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

Chynoweth, E.

Buyers are lining up for Argentina's two big state-controlled petrochemical groups, Buenos Aires-based Petroquimica General Mosconi (PGM) and Petroquimica Bahia Blance (PBB). However, feedstock supply contracts with government-owned oil group Yacientos Petroliferos Fiscales (YPG) and gas group Gas del Estado hold the key to both sales. Shell Compania Argentina Petroleo SA (CAPSA), Perez Companc, and Global Petroleum have already bought PGM tender documentation. Shell says it will bid for PGM if the feedstock contract with YPF is acceptable. In addition to price and volume, Shell says the length is critical; it wants a 15-year deal, but would settle for 11.more » YPF initially sought a five-year contract. PGM, which produces 300,000 m.t./year of aromatics, plus oxo alcohols, methanol, and methyl tert-butyl ether, has sales of $150 million/year.« less

Design, fabrication, and test of a Graphite/Epoxy Metering Shell (GEMS). [for the large space telescope

NASA Technical Reports Server (NTRS)

1975-01-01

A program to design, fabricate and test a dimensionally stable metering structure in support of the large space telescope (LST) program is discussed. Graphite/epoxy was the material selected as the only viable candidate material which can meet the stringent thermal expansion criteria of the LST. A metering shell was designed and fabricated, with emphasis on dimensional stability in conjunction with low cost. Thermal expansion test coupons extracted from the layups of the skin panels indicated the attainment of a coefficient of thermal expansion of 0.0666 micrometers/m K. Subsequent thermal vacuum chamber tests on the complete metering shell demonstrated an expansion of the 2.95-meter overall length of 0.27 micrometers/K. Static and dynamics tests, which demonstrated adequacy with respect to limit loads and stiffness, were also accomplished.

Differential Deposition for Surface Figure Corrections in Grazing Incidence X-Ray Optics

NASA Technical Reports Server (NTRS)

Ramsey, Brian D.; Kilaru, Kiranmayee; Atkins, Carolyn; Gubarev, Mikhail V.; Broadway, David M.

2015-01-01

Differential deposition corrects the low- and mid- spatial-frequency deviations in the axial figure of Wolter-type grazing incidence X-ray optics. Figure deviations is one of the major contributors to the achievable angular resolution. Minimizing figure errors can significantly improve the imaging quality of X-ray optics. Material of varying thickness is selectively deposited, using DC magnetron sputtering, along the length of optic to minimize figure deviations. Custom vacuum chambers are built that can incorporate full-shell and segmented Xray optics. Metrology data of preliminary corrections on a single meridian of full-shell x-ray optics show an improvement of mid-spatial frequencies from 6.7 to 1.8 arc secs HPD. Efforts are in progress to correct a full-shell and segmented optics and to verify angular-resolution improvement with X-ray testing.

Embedded Filaments in IRAS 05463+2652: Early Stage of Fragmentation and Star Formation Activities

NASA Astrophysics Data System (ADS)

Dewangan, L. K.; Devaraj, R.; Baug, T.; Ojha, D. K.

2017-10-01

We present a multiwavelength data analysis of IRAS 05463+2652 (hereafter I05463+2652) to study star formation mechanisms. A shell-like structure around I05463+2652 is evident in the Herschel column density map, which is not associated with any ionized emission. Based on the Herschel submillimeter images, several parsec-scale filaments (including two elongated filaments, “s-fl” and “nw-fl” having lengths of ˜6.4 and ˜8.8 pc, respectively) are investigated in the I05463+2652 site. The Herschel temperature map depicts all these features in a temperature range of ˜11-13 K. 39 clumps are identified and have masses between ˜ 70{--}945 {M}⊙ . The majority of clumps (having {M}{clump}≳ 300 {M}⊙ ) are distributed toward the shell-like structure. 175 young stellar objects (YSOs) are selected using the photometric 1-5 μm data and a majority of these YSOs are distributed toward the four areas of high column density (≳ 5× {10}21 cm-2 A V ˜ 5.3 mag) in the shell-like structure, where massive clumps and a spatial association with filament(s) are also observed. The knowledge of observed masses per unit length of elongated filaments and critical mass length reveals that they are supercritical. The filament “nw-fl” is fragmented into five clumps (having {M}{clump}˜ 100{--}545 {M}⊙ ) and contains noticeable YSOs, while the other filament “s-fl” is fragmented into two clumps (having {M}{clump}˜ 170{--}215 {M}⊙ ) without YSOs. Together, these observational results favor the role of filaments in the star formation process in I05480+2545. This study also reveals the filament “s-fl,” containing two starless clumps, at an early stage of fragmentation.

Structure and properties of silk from the African wild silkmoth Gonometa postica reared indoors

PubMed Central

Teshome, Addis; Raina, S. K.; Vollrath, Fritz

2014-01-01

Abstract African wild silkmoth, Gonometa postica Walker (Lepidoptera: Lasiocampidae), were reared indoors in order to examine the influence of rearing conditions on the structure and properties of silk cocoon shells and degummed fibers by using a scanning electron microscope, an Instron tensile tester, and a thermogravimetric analyzer. The cocoons reared indoors showed inferior quality in weight, length, width, and cocoon shell ratio compared to cocoons reared outdoors. There were no differences in cocoon shell and fiber surfaces and cross sectional structures. Cocoon shells were covered with calcium oxalate crystals with few visible fibers on their surface. Degummed fibers were smooth with minimum unfractured surfaces and globular to triangular cross sections. Indoor-reared cocoon shells had a significantly higher breaking strain, while the breaking stress was higher for cocoons reared outdoors. Fibers from indoor cocoons had a significantly higher breaking stress while outdoor fibers had higher breaking strain. Thermogravimetric analysis curves showed two main thermal reactions revealing the dehydration of water molecules and ir-reversible decomposition of the crystallites in both cocoons and fibers reared indoors and outdoors. Cocoon shells underwent additional peaks of decomposition with increased temperature. The total weight loss was higher for cocoon shells and degummed fibers from indoors. Rearing conditions (temperature and relative humidity), feeding method used, changes in total life span, days to molting, and spinning might have influenced the variation in the properties observed.The ecological and commercial significances of indoor rearing of G. postica are discussed. PMID:25373183

SlDEAD31, a Putative DEAD-Box RNA Helicase Gene, Regulates Salt and Drought Tolerance and Stress-Related Genes in Tomato.

PubMed

Zhu, Mingku; Chen, Guoping; Dong, Tingting; Wang, Lingling; Zhang, Jianling; Zhao, Zhiping; Hu, Zongli

2015-01-01

The DEAD-box RNA helicases are involved in almost every aspect of RNA metabolism, associated with diverse cellular functions including plant growth and development, and their importance in response to biotic and abiotic stresses is only beginning to emerge. However, none of DEAD-box genes was well characterized in tomato so far. In this study, we reported on the identification and characterization of two putative DEAD-box RNA helicase genes, SlDEAD30 and SlDEAD31 from tomato, which were classified into stress-related DEAD-box proteins by phylogenetic analysis. Expression analysis indicated that SlDEAD30 was highly expressed in roots and mature leaves, while SlDEAD31 was constantly expressed in various tissues. Furthermore, the expression of both genes was induced mainly in roots under NaCl stress, and SlDEAD31 mRNA was also increased by heat, cold, and dehydration. In stress assays, transgenic tomato plants overexpressing SlDEAD31 exhibited dramatically enhanced salt tolerance and slightly improved drought resistance, which were simultaneously demonstrated by significantly enhanced expression of multiple biotic and abiotic stress-related genes, higher survival rate, relative water content (RWC) and chlorophyll content, and lower water loss rate and malondialdehyde (MDA) production compared to wild-type plants. Collectively, these results provide a preliminary characterization of SlDEAD30 and SlDEAD31 genes in tomato, and suggest that stress-responsive SlDEAD31 is essential for salt and drought tolerance and stress-related gene regulation in plants.

The Zinc Finger Transcription Factor SlZFP2 Negatively Regulates Abscisic Acid Biosynthesis and Fruit Ripening in Tomato1

PubMed Central

Weng, Lin; Zhao, Fangfang; Li, Rong; Xu, Changjie; Chen, Kunsong

2015-01-01

Abscisic acid (ABA) regulates plant development and adaptation to environmental conditions. Although the ABA biosynthesis pathway in plants has been thoroughly elucidated, how ABA biosynthetic genes are regulated at the molecular level during plant development is less well understood. Here, we show that the tomato (Solanum lycopersicum) zinc finger transcription factor SlZFP2 is involved in the regulation of ABA biosynthesis during fruit development. Overexpression of SlZFP2 resulted in multiple phenotypic changes, including more branches, early flowering, delayed fruit ripening, lighter seeds, and faster seed germination, whereas down-regulation of its expression caused problematic fruit set, accelerated ripening, and inhibited seed germination. SlZFP2 represses ABA biosynthesis during fruit development through direct suppression of the ABA biosynthetic genes NOTABILIS, SITIENS, and FLACCA and the aldehyde oxidase SlAO1. We also show that SlZFP2 regulates fruit ripening through transcriptional suppression of the ripening regulator COLORLESS NON-RIPENING. Using bacterial one-hybrid screening and a selected amplification and binding assay, we identified the (A/T)(G/C)TT motif as the core binding sequence of SlZFP2. Furthermore, by RNA sequencing profiling, we found that 193 genes containing the SlZFP2-binding motifs in their promoters were differentially expressed in 2 d post anthesis fruits between the SlZFP2 RNA interference line and its nontransgenic sibling. We propose that SlZFP2 functions as a repressor to fine-tune ABA biosynthesis during fruit development and provides a potentially valuable tool for dissecting the role of ABA in fruit ripening. PMID:25637453

Trans splicing in Leishmania enriettii and identification of ribonucleoprotein complexes containing the spliced leader and U2 equivalent RNAs

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

Miller, S.I.; Wirth, D.F.

1988-06-01

The 5' ends of Leishmania mRNAs contain an identical 35-nucleotide sequence termed the spliced leader (SL) or 5' mini-exon. The SL sequence is at the 5' end of an 85-nucleotide primary transcript that contains a consensus eucaryotic 5' intron-exon splice junction immediately 3' to the SL. The SL is added to protein-coding genes immediately 3' to a consensus eucaryotic 3' intron-exon splice junction. The authors' previous work demonstrated possible intermediates in discontinuous mRNA processing that contain the 50 nucleotides of the SL primary transcript 3' to the SL, the SL intron sequence (SLIS). These RNAs have a 5' terminus atmore » the splice junction of the SL and the SLIS. The authors examined a Leishmania nuclear extract for these RNAs in ribonucleoprotein (RNP) particles. Density centrifugation analysis showed that the SL RNA is predominately in RNP complexes at 60S, while the SLIS-containing RNAs are in complexes at 40S. They also demonstrated that the SLIS can be released from polyadenylated RNA by incubation with a HeLa cell extract containing debranching enzymatic activity. These data suggested that Leishmania enriettii mRNAs are assembled by bimolecular or trans splicing as has been recently demonstrated for Trypanosoma brucei. Furthermore, they determined the partial sequence of the Leishmania U2 equivalent RNA and demonstrated that it cosediments with the SL RNA at 60S in a nuclear extract. These RNP particles may be analogous to so-called spliceosomes that have been demonstrated in other systems.« less

A rare complex DNA rearrangement in the murine Steel gene results in exon duplication and a lethal phenotype.

PubMed

Chandra, Saurabh; Kapur, Reuben; Chuzhanova, Nadia; Summey, Victoria; Prentice, David; Barker, Jane; Cooper, David N; Williams, David A

2003-11-15

Kit ligand (Kitl), encoded by the Steel (Sl) locus, plays an essential role in hematopoiesis, gametogenesis, and melanogenesis during both embryonic and adult life. We have characterized a new spontaneous mutant of the Sl locus in mice designated KitlSl-20J that arose in the breeding colony at Jackson Laboratories. Heterozygous KitlSl-20J mice display a white belly spot and intercrossing results in an embryonic lethal phenotype in the homozygous state. Analysis of homozygous embryos demonstrated a significant reduction in fetal liver cellularity, colony forming unit-erythroid (CFU-E) progenitors, and a total absence of germ cells. Although expressed in vivo, recombinant mutant protein demonstrated loss of bioactivity that was correlated with lack of receptor binding. Analysis of the Sl gene transcripts in heterozygous KitlSl-20J mice revealed an in-frame tandem duplication of exon 3. A long-range polymerase chain reaction (PCR) strategy using overlapping primers in exon 3 amplified an approximately 7-kilobase (kb) product from DNA isolated from heterozygous KitlSl-20J mice but not from wild-type DNA that contained sequences from both introns 2 and 3 and an inverted intron 2 sequence, suggesting a complex rearrangement as the mechanism of the mutation. "Complexity analysis" of the sequence of the amplified product strongly suggests that local DNA motifs may have contributed to the generation of this spontaneous KitlSl-20J allele, likely mediated by a 2-step process. The KitlSl-20J mutation is a unique KitlSl allele and represents an unusual mechanism of mutation.

Changes in Ocean Circulation with an Ice-Free Arctic: Reconstructing Early Holocene Arctic Ocean Circulation Using Geochemical Signals from Individual Neogloboquadrina pachyderma (sinistral) Shells

NASA Astrophysics Data System (ADS)

Livsey, C.; Spero, H. J.; Kozdon, R.

2016-12-01

The impacts of sea ice decrease and consequent hydrologic changes in the Arctic Ocean will be experienced globally as ocean and atmospheric temperatures continue to rise, though it is not evident to what extent. Understanding the structure of the Arctic water column during the early/mid Holocene sea ice minimum ( 6-10 kya), a post-glacial analogue of a seasonally ice-free Arctic, will help us to predict what the changes we can expect as the Earth warms over the next century. Neogloboquadrina pachyderma (sinistral; Nps) is a species of planktonic foraminifera that dominates assemblages in the polar oceans. This species grows its chambers (ontogenetic calcite) in the surface waters and subsequently descends through the water column to below the mixed layer where it quickly adds a thick crust of calcite (Kohfeld et al., 1996). Therefore, geochemical signals from both the surface waters and sub-mixed layer depths are captured within single Nps shells. We were able to target <5 μm - sized domains for δ18O using secondary ion mass spectrometry (SIMS), therefore capturing signals from both the ontogenetic and crust calcite in single Nps shells. This data was combined with laser ablation- inductively coupled mass spectrometry (LA-ICPMS) Mg/Ca profiles of trace metals through the two layers of calcite of the same shells, to determine the thermal structure of the water column. Combining δ18O, temperature, and salinity gradients from locations across the Arctic basin allow us to reconstruct the hydrography of the early Holocene Arctic sea ice minimum. These results will be compared with modern Arctic water column characteristics in order to develop a conceptual model of Arctic Ocean oceanographic change due to global warming. Kohfeld, K.E., Fairbanks, R.G., Smith, S.L., Walsh, I.D., 1996. Neogloboquadrina pachyderma(sinistral coiling) as paleoceanographic tracers in polar oceans: Evidence from northeast water polynya plankton tows, sediment traps, and surface sediments. Paleoceanography 11, 679-699.

Do infants retain the statistics of a statistical learning experience? Insights from a developmental cognitive neuroscience perspective

PubMed Central

2017-01-01

Statistical structure abounds in language. Human infants show a striking capacity for using statistical learning (SL) to extract regularities in their linguistic environments, a process thought to bootstrap their knowledge of language. Critically, studies of SL test infants in the minutes immediately following familiarization, but long-term retention unfolds over hours and days, with almost no work investigating retention of SL. This creates a critical gap in the literature given that we know little about how single or multiple SL experiences translate into permanent knowledge. Furthermore, different memory systems with vastly different encoding and retention profiles emerge at different points in development, with the underlying memory system dictating the fidelity of the memory trace hours later. I describe the scant literature on retention of SL, the learning and retention properties of memory systems as they apply to SL, and the development of these memory systems. I propose that different memory systems support retention of SL in infant and adult learners, suggesting an explanation for the slow pace of natural language acquisition in infancy. I discuss the implications of developing memory systems for SL and suggest that we exercise caution in extrapolating from adult to infant properties of SL. This article is part of the themed issue ‘New frontiers for statistical learning in the cognitive sciences’. PMID:27872372

Comparison between S+L- assay and LacZ marker rescue assay for detecting replication-competent gammaretroviruses.

PubMed

Hashimoto-Gotoh, A; Yoshikawa, R; Miyazawa, T

2015-09-01

To avoid contamination of adventitious gammaretroviruses in biological products such as vaccines, it is necessary to check the master seed cells for manufacturing. There are several assays to detect infectious gammaretroviruses. Among these, sarcoma-positive, leukemia-negative (S+L-) assay is a classical infectivity assay, which is often recommended in governmental guidelines. The S+L- cells used in S+L- assay generate unique focus upon the infection of replication-competent gammaretroviruses. Although S+L- assay is well recognized for the detection, their applicability is questionable in some cases. On the other hand, LacZ marker rescue (LMR) assay detects infectious gammaretroviruses by transducing LacZ marker gene to the target cells, which shows lacZ-positive foci if the infectious virus is present. In this study, we compared LMR and S+L- assays for detection of a variety of endogenous and exogenous gammaretroviruses. As results, LMR assay could detect all gammaretroviruses examined. On the other hand, S+L- assay using feline S+L- cells, termed QN10S, could not detect porcine endogenous retrovirus (PERV) subgroups A/B. Further, S+L- mink cells could not detect feline leukemia virus subgroups B in addition to PERV-A/B. These data indicate that LMR assay is better suited to detect wider range of gammaretroviruses. Copyright © 2015 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

New Orleans before and after Hurricanes Katrina/Rita: a quasi-experiment of the association between soil lead and children's blood lead.

PubMed

Zahran, Sammy; Mielke, Howard W; Gonzales, Christopher R; Powell, Eric T; Weiler, Stephan

2010-06-15

Prior to Hurricanes Katrina and Rita (HKR), significant associations were noted between soil lead (SL) and blood lead (BL) in New Orleans. Engineering failure of New Orleans levees and canal walls after HKR set the stage for a quasi-experiment to evaluate BL responses by 13 306 children to reductions in SL. High density soil surveying conducted in 46 census tracts before HKR was repeated after the flood. Paired t test results show that SL decreased from 328.54 to 203.33 mg/kg post-HKR (t = 3.296, p < or = 0.01). Decreases in SL are associated with declines in children's BL response (r = 0.308, p < or = 0.05). When SL decreased at least 1%, median children's BL declined 1.55 microg/dL. Declines in median BL are largest in census tracts with > or =50% decrease in SL. Also individual BL in children was predicted as a function of SL, adjusting for age, year of observation, and depth of flood waters. At the individual scale, BL decreased significantly in post-HKR as a function of SL, with BL decreases ranging from b = -1.20 to -1.65 microg/dL, depending on the decline of SL and whether children were born in the post-HKR period. Our results support policy to improve soil conditions for children.

Do infants retain the statistics of a statistical learning experience? Insights from a developmental cognitive neuroscience perspective.

PubMed

Gómez, Rebecca L

2017-01-05

Statistical structure abounds in language. Human infants show a striking capacity for using statistical learning (SL) to extract regularities in their linguistic environments, a process thought to bootstrap their knowledge of language. Critically, studies of SL test infants in the minutes immediately following familiarization, but long-term retention unfolds over hours and days, with almost no work investigating retention of SL. This creates a critical gap in the literature given that we know little about how single or multiple SL experiences translate into permanent knowledge. Furthermore, different memory systems with vastly different encoding and retention profiles emerge at different points in development, with the underlying memory system dictating the fidelity of the memory trace hours later. I describe the scant literature on retention of SL, the learning and retention properties of memory systems as they apply to SL, and the development of these memory systems. I propose that different memory systems support retention of SL in infant and adult learners, suggesting an explanation for the slow pace of natural language acquisition in infancy. I discuss the implications of developing memory systems for SL and suggest that we exercise caution in extrapolating from adult to infant properties of SL.This article is part of the themed issue 'New frontiers for statistical learning in the cognitive sciences'. © 2016 The Author(s).

Small angle neutron scattering from 1-alkyl-3-methylimidazolium hexafluorophosphate ionic liquids ([Cnmim][PF6], n=4, 6, and 8)

NASA Astrophysics Data System (ADS)

Hardacre, Christopher; Holbrey, John D.; Mullan, Claire L.; Youngs, Tristan G. A.; Bowron, Daniel T.

2010-08-01

The presence of local anisotropy in the bulk, isotropic, and ionic liquid phases—leading to local mesoscopic inhomogeneity—with nanoscale segregation and expanding nonpolar domains on increasing the length of the cation alkyl-substituents has been proposed on the basis of molecular dynamics (MD) simulations. However, there has been little conclusive experimental evidence for the existence of intermediate mesoscopic structure between the first/second shell correlations shown by neutron scattering on short chain length based materials and the mesophase structure of the long chain length ionic liquid crystals. Herein, small angle neutron scattering measurements have been performed on selectively H/D-isotopically substituted 1-alkyl-3-methylimidazolium hexafluorophosphate ionic liquids with butyl, hexyl, and octyl substituents. The data show the unambiguous existence of a diffraction peak in the low-Q region for all three liquids which moves to longer distances (lower Q), sharpens, and increases in intensity with increasing length of the alkyl substituent. It is notable, however, that this peak occurs at lower values of Q (longer length scale) than predicted in any of the previously published MD simulations of ionic liquids, and that the magnitude of the scattering from this peak is comparable with that from the remainder of the amorphous ionic liquid. This strongly suggests that the peak arises from the second coordination shells of the ions along the vector of alkyl-chain substituents as a consequence of increasing the anisotropy of the cation, and that there is little or no long-range correlated nanostructure in these ionic liquids.

Earth resources requirements Skylab missions SL-1/SL-2, SL-3, and SL-4. Appendix B: Mission requirements

NASA Technical Reports Server (NTRS)

1972-01-01

Earth resources requirements to be investigated by Skylab missions 1 through 4 are presented tabularly. Areas to be investigated include: (1) agriculture, range, and forestry; (2) geology; (3) continental water resources; (4) ocean investigations; (5) atmospheric investigations; (6) coastal zones, shoals, and bays; (7) remote sensing techniques; and (8) cartography.

Glycolipid Biosurfactants Activate, Dimerize, and Stabilize Thermomyces lanuginosus Lipase in a pH-Dependent Fashion.

PubMed

Madsen, Jens Kvist; Kaspersen, Jørn Døvling; Andersen, Camilla Bertel; Nedergaard Pedersen, Jannik; Andersen, Kell Kleiner; Pedersen, Jan Skov; Otzen, Daniel E

2017-08-15

We present a study of the interactions between the lipase from Thermomyces lanuginosus (TlL) and the two microbially produced biosurfactants (BSs), rhamnolipid (RL) and sophorolipid (SL). Both RL and SL are glycolipids; however, RL is anionic, while SL is a mixture of anionic and non-ionic species. We investigate the interactions of RL and SL with TlL at pH 6 and 8 and observe different effects at the two pH values. At pH 8, neither RL nor SL had any major effect on TlL stability or activity. At pH 6, in contrast, both surfactants increase TlL's thermal stability and fluorescence and activity measurements indicate interfacial activation of TlL, resulting in 3- and 6-fold improved activity in SL and RL, respectively. Nevertheless, isothermal titration calorimetry reveals binding of only a few BS molecules per lipase. Size-exclusion chromatography and small-angle X-ray scattering suggest formation of TlL dimers with binding of small amounts of either RL or SL at the dimeric interface, forming an elongated complex. We conclude that RL and SL are compatible with TlL and constitute promising green alternatives to traditional surfactants.

A comparative analysis of somatolactin-related immunoreactivity in the pituitaries of four neopterygian fishes and one chondrostean fish: an immunohistochemical study.

PubMed

Dores, R M; Hoffman, N E; Chilcutt-Ruth, T; Lancha, A; Brown, C; Marra, L; Youson, J

1996-04-01

An antiserum to cod somatolactin (SL) was used for immunohistochemical screening for the pars intermedia of two teleosts (Oreochromis mossambicus and Gymothorax meleagris), two holostean fishes (Lepisosteus osseus and Amia calva), and a chondrostean fish (Acipenser fulvescens) for SL-immunopositive (SL-IR) cells. As expected, a subset of the epithelial cells in the pars intermedia of O. mossambicus (tilapia) was immunopositive for SL, and the remainder of the epithelial cells was immunopositive for alpha-MSH-specific antiserum (alpha-MSH-IR). SL-IR was not detected in any of the epithelial cells in the pars intermedia of the moray eel G. meleagris. To determine whether SL-IR could be detected in nonteleost fishes, immunohistochemical analyses were done on the pituitaries of two holostean fishes and one chondrostean fish. In the pars intermedia of the gar, L. osseus, a subset of cells was immunopositive for alpha-MSH only. However, in the pars intermedia of the bowfin, A. calva, all of the epithelial cells indicated the presence of both SL and alpha-MSH. Finally, no SL-positive cells were detected in the pars intermedia of the sturgeon, A. fulvescens.

Training socially responsive health care graduates: is service learning an effective educational approach?

PubMed

Mc Menamin, Ruth; Mc Grath, Margaret; Cantillon, Peter; Mac Farlane, Anne

2014-04-01

Health care educators strive to train graduates who are socially responsive and can act as "change agents" for communities they serve. Service learning (SL) is increasingly being used to teach the social aspects of health care and develop students' social responsiveness. However, the effectiveness of SL as an educational intervention has not been established. To assess the evidence for the effectiveness of SL. Seven electronic databases were searched up to 2012 and included all articles on SL for pre-professional health care students. Hand searching was also conducted. A total of 1485 articles were identified, 53 fulfilled the search and quality appraisal criteria and were reviewed across six domains of potential SL effects: (i) personal and interpersonal development; (ii) understanding and applying knowledge; (iii) engagement, curiosity and reflective practice; (iv) critical thinking; (v) perspective transformation and (vi) citizenship. While SL experiences appear highly valued by educators and students the effectiveness of SL remains unclear. SL is different from other forms of experiential learning because it explicitly aims to establish reciprocity between all partners and increase students' social responsiveness. Impact studies based on the interpretative paradigm, aligned with the principles of social accountability and including all stakeholder perspectives are necessary.

Antifungal starter culture for packed bread: influence of two storage conditions.

PubMed

Gerez, Carla L; Fornaguera, María J; Obregozo, Mariano D; Font de Valdez, Graciela; Torino, María I

2015-01-01

In this study, we analyzed the conservation of a semi-liquid bio-preserver (SL778) developed with Lactobacillus plantarum CRL 778, a lactic acid bacterium (LAB) having antifungal activity. The characteristics of the SL778 starter remained stable during a 14-day storage at 4°C. At -20°C, cell viability and organic acid concentration showed a significant (p<0.05) decrease after 7 days. These differences observed between the storage temperatures tested were reflected in the acidification activity of SL778 during dough fermentation. However, SL778 maintained its antifungal efficacy up to a 14-day storage at both temperatures. Sensory attributes (acidic and spicy tastes and acidic smell) of breads manufactured with starter SL778 (stored at 4 or -20°C) were evaluated. No undesirable difference was detected with respect to bread control without SL778 and bread manufactured with SL778 (stored at 4 or -20°C). In conclusion, the SL778 semi-liquid bio-preserver can be stored at 4 or -20°C without modifying its antifungal activity during 14 days. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Dynamic balance sensory motor control and symmetrical or asymmetrical equilibrium training.

PubMed

Guillou, Emmanuel; Dupui, Philippe; Golomer, Eveline

2007-02-01

Determine whether symmetrical or asymmetrical equilibrium training can enhance the proprioceptive input of the left versus right supporting leg (SL) motor control. Proprioceptive input was tested using a seesaw platform through a cross-sectional study. The total spectral energy was recorded and divided into 0-2 and 2-20Hz frequency bands. Experts in asymmetrical tasks (soccer players) were compared to experts in symmetrical tasks (dancers, acrobats) and untrained subjects according to pitch versus roll imbalance direction on each SL. Regarding the low frequency band, spectral energy values were lower for experts than for untrained subjects in the roll direction only, whatever the SL (p<0.05). Regarding the high frequency band, spectral energy values were lower for the left SL compared to the right one for soccer players only (p<0.05). Furthermore, soccer players also exhibited lower values than other subjects on the left SL. Asymmetrical equilibrium training minimizes the proprioceptive input, emphasizing the role of the biomechanical component in postural regulation. Testing athletes on a spontaneous unstable platform is a way to accurately discriminate each SL performance for one type of sport training. In sport medicine rehabilitation, injured SL could be detected with this protocol comparing it with healthy SL.

Methyl phenlactonoates are efficient strigolactone analogs with simple structure

PubMed Central

Jamil, Muhammad; Kountche, Boubacar A; Haider, Imran; Guo, Xiujie; Ntui, Valentine O; Jia, Kun-Peng; Hameed, Umar S; Nakamura, Hidemitsu; Lyu, Ying; Jiang, Kai; Hirabayashi, Kei; Tanokura, Masaru; Arold, Stefan T; Asami, Tadao

2018-01-01

abstract Strigolactones (SLs) are a new class of phytohormones that also act as germination stimulants for root parasitic plants, such as Striga spp., and as branching factors for symbiotic arbuscular mycorrhizal fungi. Sources for natural SLs are very limited. Hence, efficient and simple SL analogs are needed for elucidating SL-related biological processes as well as for agricultural applications. Based on the structure of the non-canonical SL methyl carlactonoate, we developed a new, easy to synthesize series of analogs, termed methyl phenlactonoates (MPs), evaluated their efficacy in exerting different SL functions, and determined their affinity for SL receptors from rice and Striga hermonthica. Most of the MPs showed considerable activity in regulating plant architecture, triggering leaf senescence, and inducing parasitic seed germination. Moreover, some MPs outperformed GR24, a widely used SL analog with a complex structure, in exerting particular SL functions, such as modulating Arabidopsis roots architecture and inhibiting rice tillering. Thus, MPs will help in elucidating the functions of SLs and are promising candidates for agricultural applications. Moreover, MPs demonstrate that slight structural modifications clearly impact the efficiency in exerting particular SL functions, indicating that structural diversity of natural SLs may mirror a functional specificity. PMID:29300919

Neurocognitive mechanisms of statistical-sequential learning: what do event-related potentials tell us?

PubMed Central

Daltrozzo, Jerome; Conway, Christopher M.

2014-01-01

Statistical-sequential learning (SL) is the ability to process patterns of environmental stimuli, such as spoken language, music, or one’s motor actions, that unfold in time. The underlying neurocognitive mechanisms of SL and the associated cognitive representations are still not well understood as reflected by the heterogeneity of the reviewed cognitive models. The purpose of this review is: (1) to provide a general overview of the primary models and theories of SL, (2) to describe the empirical research – with a focus on the event-related potential (ERP) literature – in support of these models while also highlighting the current limitations of this research, and (3) to present a set of new lines of ERP research to overcome these limitations. The review is articulated around three descriptive dimensions in relation to SL: the level of abstractness of the representations learned through SL, the effect of the level of attention and consciousness on SL, and the developmental trajectory of SL across the life-span. We conclude with a new tentative model that takes into account these three dimensions and also point to several promising new lines of SL research. PMID:24994975

Down-regulation of SlIAA15 in tomato altered stem xylem development and production of volatile compounds in leaf exudates.

PubMed

Deng, Wei; Yan, Fang; Liu, Minchun; Wang, Xinyu; Li, Zhengguo

2012-08-01

The Aux/IAA family genes encode short-lived nuclear proteins that function as transcriptional regulators in auxin signal transduction. Aux/IAA genes have been reported to control many processes of plant development. Our recent study showed that down-regulation of SlIAA15 in tomato reduced apical dominance, altered pattern of axillary shoot development, increased lateral root formation and leaves thickness. The SlIAA15 suppressed lines display strong reduction of trichome density, suggesting that SlIAA15 is involved in trichome formation. Here, we reported that SlIAA15-suppressed transgenic lines display increased number of xylem cells compared to wild-type plants. Moreover, the monoterpene content in trichome exudates are significantly reduced in SlIAA15 down-regulated leaves. The results provide the roles of SlIAA15 in production of volatile compounds in leaf exudates and xylem development, clearly indicating that members of the Aux/IAA gene family can play distinct and specific functions. 

Karrikins force a rethink of strigolactone mode of action

PubMed Central

Waters, Mark T.; Scaffidi, Adrian; Flematti, Gavin R.; Smith, Steven M.

2012-01-01

Strigolactones (SL) and karrikins (KAR) both contain essential butenolide moieties, and both require the F-box protein MAX2 to control seed germination and photomorphogenesis in Arabidopsis thaliana. A new discovery that SL and KAR also require related α/β-hydrolase proteins for such activity suggests that they operate through a similar molecular mechanism. Based on structural similarity, a previously proposed mode of action for SL was also considered for KAR, but recent structure-activity studies suggest that this mechanism may not apply. Here we rationalise these observations into a hypothesis whereby different α/β-hydrolases distinguish SL and KAR by virtue of their non-butenolide moieties and catalyze nucleophilic attack on the butenolide. The products would be different for SL and KAR, and in the case of SL they have no biological activity. The inference is that nucleophilic attack on SL and KAR by α/β-hydrolases is required for their bioactivity, but the hydrolysis products are not. PMID:22827937

SL(2,R) duality-symmetric action for electromagnetic theory with electric and magnetic sources

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

Lee, Choonkyu, E-mail: cklee@phya.snu.ac.kr; School of Physics, Korea Institute for Advanced Study, Seoul 130-722; Min, Hyunsoo, E-mail: hsmin@dirac.uos.ac.kr

2013-12-15

For the SL(2,R) duality-invariant generalization of Maxwell electrodynamics in the presence of both electric and magnetic sources, we formulate a local, manifestly duality-symmetric, Zwanziger-type action by introducing a pair of four-potentials A{sup μ} and B{sup μ} in a judicious way. On the two potentials A{sup μ} and B{sup μ} the SL(2,R) duality transformation acts in a simple linear manner. In quantum theory including charged source fields, this action can be recast as a SL(2,Z)-invariant action. Also given is a Zwanziger-type action for SL(2,R) duality-invariant Born–Infeld electrodynamics which can be important for D-brane dynamics in string theory. -- Highlights: •We formulatemore » a local, manifestly duality-symmetric, Zwanziger-type action. •Maxwell electrodynamics is generalized to include dilaton and axion fields. •SL(2,R) symmetry is manifest. •We formulate a local, manifestly duality-symmetric, nonlinear Born–Infeld action with SL(2,R) symmetry.« less

Critical Anisotropies of a Geometrically-Frustrated Triangular-Lattice

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

Swanson, Mason R; Haraldsen, Jason T; Fishman, Randy Scott

2009-01-01

This work examines the critical anisotropy required for the local stability of the collinear ground states of a geometrically-frustrated triangular-lattice antiferromagnet (TLA). Using a Holstein-Primakoff expansion, we calculate the spin-wave frequencies for the 1, 2, 3, 4, and 8-sublattice (SL) ground states of a TLA with up to third neighbor interactions. Local stability requires that all spin-wave frequencies are real and positive. The 2, 4, and 8-SL phases break up into several regions where the critical anisotropy is a different function of the exchange parameters. We find that the critical anisotropy is a continuous function everywhere except across the 2-SL/3-SLmore » and 3-SL/4-SL phase boundaries, where the 3-SL phase has the higher critical anisotropy.« less

Comparative reproductive biology of three dominant myctophids of the genus Diaphus on the slope region of the East China Sea

NASA Astrophysics Data System (ADS)

Sassa, Chiyuki; Tanaka, Hiroshige; Ohshimo, Seiji

2016-09-01

We examined the reproductive biology of three dominant pseudoceanic myctophids, Diaphus garmani, D. chrysorhynchus, and D. watasei, on the slope region of the East China Sea. Overall, females were more abundant in D. garmani and D. chrysorhynchus, while males were more abundant in D. watasei. The gonadosomatic index (GSI) at 50% sexual maturity of females of D. garmani, D. chrysorhynchus, and D. watasei was 3.65, 3.92, and 6.27, respectively. Based on these criteria, females of each species can mature at sizes larger than 42, 71, and 120 mm standard length (SL), respectively. In all three species, GSI of females showed high values during summer, i.e. the primary spawning season, and occurrence of females with hydrated ovaries was restricted to the daytime (0600-1530 h) in the mesopelagic layer of 270-450 m depth. Oocytes at various sizes were found in mature ovaries, indicating that they are multiple spawners. Spawning frequencies were estimated to be approximately 3-9 days. Mean egg size at hydration and batch fecundity was respectively smallest and lowest in D. garmani (0.60 mm and 612-2200 eggs) and largest and highest in D. watasei (0.65 mm and 10,356-44,879 eggs). Batch fecundity increased linearly with SL in all species, with a steeper slope in D. watasei. Diaphus garmani is characterized by early maturation at a smaller size, while D. watasei channels a larger part of the energy budget into somatic growth during the juvenile and later immature stages (<120 mm SL) than the other two species and subsequently reproduces at a larger size as mature adults.

Scalar dissipation, diffusion and dilatation in turbulent H2-air premixed flames with complex chemistry

NASA Astrophysics Data System (ADS)

Swaminathan, N.; Bilger, R. W.

2001-09-01

Characteristics of the scalar dissipation rate, N, of a progress variable, c, based on temperature in turbulent H2-air premixed flames are studied via direct numerical simulation with complex chemical kinetics for a range of flow/flame conditions (Baum et al 1994 J. Fluid Mech. 281 1). The flames are in the usually designated wrinkled-flamelet and well-stirred reactor regimes. The normalized conditional average, Nζ+, is observed to be higher than the corresponding planar laminar value because of strain thinning and the augmentation of laminar transport by turbulence within the flame front. Also, Nζ+ varies strongly across the flame-brush when u'/Sl is high. N has a log-normal distribution when u'/Sl is small and has a long negative tail for cases where u'/Sl is large. In the flame with φ = 0.5, \\widetilde{N_{\\zeta}^ + }/\\widetilde{N_^ + }" shows some sensitivity to Pζ and the sensitivity seems to be weak in a φ = 0.35 flame. The effect of turbulence on <ζ> is observed to be marginal. The conditional diffusion and the conditional dilatation, <∇ · u|ζ>, peak on the unburnt side of the flame-front and are higher than the corresponding laminar flame values in all cases. The inter-relationship among the conditional dissipation, diffusion, dilatation and velocity is discussed. A model for uζ obtained from the conditional dilatation is found not to perform as well as a linear model. The above results are limited, however, because, the flow field is two dimensional, hydrogen is used as the fuel, the range of dynamic length scales is small and the sample size is small.

Identification and functional analysis of the HvD14 gene involved in strigolactone signaling in Hordeum vulgare.

PubMed

Marzec, Marek; Gruszka, Damian; Tylec, Piotr; Szarejko, Iwona

2016-11-01

In this study, the barley HvD14 gene encoding α/β hydrolase, which is involved in strigolactone (SL) signaling, was identified. Bioinformatics analysis revealed that the identified gene is an orthologue of the D14, AtD14 and PhDAD2 genes that have been described in rice, Arabidopsis thaliana and petunia, respectively. Using TILLING strategy, an hvd14.d mutant that carried the G725A transition, located in the second exon, was identified. This mutation led to the substitution of a highly conserved glycine-193 to glutamic acid in the conserved fragment of the α/β hydrolase domain of the HvD14 protein. The plants that carry the hvd14.d allele were semi-dwarf and produced a higher number of tillers in comparison to the wild-type (WT) parent cultivar. Additionally, the root architecture of mutant plants was affected: the total length of the seminal roots was significantly reduced, and the density of the lateral roots was higher than in the WT. Plants with the hvd14.d allele were insensitive to treatment with GR24, which is the synthetic analogue of SL. Analysis of the indole-3-acetic acid (IAA) concentration in the lateral buds showed no differences between the WT and mutant plants. By contrast, the WT seedlings treated with GR24 developed a lower number of tillers, longer primary roots with a reduced number of lateral roots and had an increased concentration of IAA in lateral buds. This paper describes the first barley SL mutant and shows the potential functions of SLs in barley growth and development. © 2016 Scandinavian Plant Physiology Society.

DNS study of dependence of bulk consumption velocity in a constant-density reacting flow on turbulence and mixture characteristics

NASA Astrophysics Data System (ADS)

Yu, Rixin; Lipatnikov, Andrei N.

2017-06-01

3D Direct Numerical Simulation (DNS) study of propagation of a single-reaction wave in forced, statistically stationary, homogeneous, isotropic, and constant-density turbulence was performed in order to evaluate both developing UTt and fully developed UTs bulk turbulent consumption velocities by independently varying a ratio of 0.5 ≤u'/SL≤ 90 of the r.m.s. turbulent velocity to the laminar wave speed and a ratio of 0.39 ≤L11/δF≤ 12.5 of the longitudinal integral length scale of the turbulence to the laminar wave thickness. Accordingly, the Damköhler D a =(L11SL ) /(u'δF ) and Karlovitz K a =δF/(SLτη ) numbers were varied from 0.01 to 24.7 and from 0.36 to 587, respectively. Here, τη is the Kolmogorov time scale. The obtained DNS data show that, at sufficiently low Da, the fully developed ratio of UTs/u' is mainly controlled by Da and scales as √{D a }. However, such a scaling should not be extrapolated to high Da. The higher Da (or the lower Ka), the less pronounced dependence of UTs/u' on a ratio of L11/δF. Moreover, scaling laws UT∝u'αSL1 -α(L11/δF ) β are substantially different for developing UTt and fully developed UTs, i.e., the scaling exponents α and, especially, β depend on the wave-development time. Furthermore, α and, especially, β depend on a method used to evaluate the developing UTt. Such effects can contribute to significant scatter of expressions for UT or ST as a function of {u', SL, L11, δF}, obtained by parameterizing various experimental databases.

Exposure to disinfectants (soap or hydrogen peroxide) increases tolerance to permethrin in Anopheles gambiae populations from the city of Yaoundé, Cameroon

PubMed Central

2014-01-01

Background The rapid expansion of insecticide resistance is limiting the efficiency of malaria vector control interventions. However, current knowledge of factors inducing pyrethroid resistance remains incomplete. In the present study, the role of selection at the larval stage by disinfectants, such as soap and hydrogen peroxide (H2O2), on adult mosquito resistance to permethrin was investigated. Methods Field Anopheles gambiae sensu lato larvae, were exposed to variable concentrations of soap and H2O2. Larvae surviving to acute toxicity assays after 24 hours were reared to the adult stage and exposed to permethrin. The susceptibility level of adults was compared to the untreated control group. The effect of soap or hydrogen peroxide selection on the length of larval development and emergence rate was assessed. Result Larval bioassays analysis showed a more acute effect of hydrogen peroxide on mosquito larvae compared to soap. The regression lines describing the dose mortality profile showed higher mean and variance to hydrogen peroxide than to soap. The duration of larval development (<5 days) and adults emergence rates (1 to 77%) were shorter and lower compare to control. Anopheles gambiae s.l. larvae surviving to selection with either soap or hydrogen peroxide or both, produced adults who were up to eight-times more resistant to permethrin than mosquitoes from the untreated control group. Conclusion The present study shows that selective pressure exerted by non-insecticidal compounds such as soap and hydrogen peroxide affect An. gambiae s.l. tolerance to pyrethroids. This requires further studies with regard to the adaptation of An. gambiae s.l. to polluted habitats across sub-Saharan Africa cities. PMID:25086741

Exposure to disinfectants (soap or hydrogen peroxide) increases tolerance to permethrin in Anopheles gambiae populations from the city of Yaoundé, Cameroon.

PubMed

Antonio-Nkondjio, Christophe; Youmsi-Goupeyou, Marlene; Kopya, Edmond; Tene-Fossog, Billy; Njiokou, Flobert; Costantini, Carlo; Awono-Ambene, Parfait

2014-08-03

The rapid expansion of insecticide resistance is limiting the efficiency of malaria vector control interventions. However, current knowledge of factors inducing pyrethroid resistance remains incomplete. In the present study, the role of selection at the larval stage by disinfectants, such as soap and hydrogen peroxide (H2O2), on adult mosquito resistance to permethrin was investigated. Field Anopheles gambiae sensu lato larvae, were exposed to variable concentrations of soap and H2O2. Larvae surviving to acute toxicity assays after 24 hours were reared to the adult stage and exposed to permethrin. The susceptibility level of adults was compared to the untreated control group. The effect of soap or hydrogen peroxide selection on the length of larval development and emergence rate was assessed. Larval bioassays analysis showed a more acute effect of hydrogen peroxide on mosquito larvae compared to soap. The regression lines describing the dose mortality profile showed higher mean and variance to hydrogen peroxide than to soap. The duration of larval development (<5 days) and adults emergence rates (1 to 77%) were shorter and lower compare to control. Anopheles gambiae s.l. larvae surviving to selection with either soap or hydrogen peroxide or both, produced adults who were up to eight-times more resistant to permethrin than mosquitoes from the untreated control group. The present study shows that selective pressure exerted by non-insecticidal compounds such as soap and hydrogen peroxide affect An. gambiae s.l. tolerance to pyrethroids. This requires further studies with regard to the adaptation of An. gambiae s.l. to polluted habitats across sub-Saharan Africa cities.

Effects of dietary menadione on the activity of antioxidant enzymes in abalone, Haliotis discus hannai Ino

NASA Astrophysics Data System (ADS)

Fu, Jinghua; Xu, Wei; Mai, Kangsen; Zhang, Wenbing; Feng, Xiuni; Liufu, Zhiguo

2012-01-01

A 240-day growth experiment in a re-circulating water system was conducted to investigate the effects of dietary menadione on the growth and antioxidant responses of abalone Haliotis discus hannai Ino. Triplicate groups of juvenile abalone (initial weight: 1.19 ± 0.01 g; shell length: 19.23 ± 0.01 mm) were fed to satiation with 3 semi-purified diets containing 0, 10, and 1 000 mg menadione sodium bisulfite (MSB)/kg, respectively. Results show that there were no significant differences in the rate of weight gain or in the daily increment in shell length of abalone among different treatments. Activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione S-transferase (GST) and glutathione reductase (GR) in viscera were significantly decreased with dietary menadione. However, activities of these enzymes except for GPX in muscle were increased. Therefore, antioxidant responses of abalone were increased in muscle and decreased in viscera by dietary menadione.

A lithographically patterned capacitor with horizontal nanowires of length 2.5 mm.

PubMed

Yan, Wenbo; Thai, Mya Le; Dutta, Rajen; Li, Xiaowei; Xing, Wendong; Penner, Reginald M

2014-04-09

A symmetrical hybrid capacitor consisting of interdigitated, horizontal nanowires is described. Each of the 750 nanowires within the capacitor is 2.5 mm in length, consisting of a gold nanowire core (40 × ≈200 nm) encapsulated within a hemicylindrical shell of δ-phase MnO2 (thickness = 60-220 nm). These Au@δ-MnO2 nanowires are patterned onto a planar glass surface using lithographically patterned nanowire electrodeposition (LPNE). A power density of 165 kW/kg and energy density of 24 Wh/kg were obtained for a typical nanowire array in which the MnO2 shell thickness was 68 ± 8 nm. Capacitors incorporating these ultralong nanowires lost ≈10% of their capacity rapidly, during the first 20 discharge cycles, and then retained 90% of their maximum capacity for the ensuing 6000 cycles. The ability of capacitors consisting of ultralong Au@δ-MnO2 nanowires to simultaneously deliver high power and high capacity with acceptable cycle life is demonstrated.

Size distribution of magnetic iron oxide nanoparticles using Warren-Averbach XRD analysis

NASA Astrophysics Data System (ADS)

Mahadevan, S.; Behera, S. P.; Gnanaprakash, G.; Jayakumar, T.; Philip, J.; Rao, B. P. C.

2012-07-01

We use the Fourier transform based Warren-Averbach (WA) analysis to separate the contributions of X-ray diffraction (XRD) profile broadening due to crystallite size and microstrain for magnetic iron oxide nanoparticles. The profile shape of the column length distribution, obtained from WA analysis, is used to analyze the shape of the magnetic iron oxide nanoparticles. From the column length distribution, the crystallite size and its distribution are estimated for these nanoparticles which are compared with size distribution obtained from dynamic light scattering measurements. The crystallite size and size distribution of crystallites obtained from WA analysis are explained based on the experimental parameters employed in preparation of these magnetic iron oxide nanoparticles. The variation of volume weighted diameter (Dv, from WA analysis) with saturation magnetization (Ms) fits well to a core shell model wherein it is known that Ms=Mbulk(1-6g/Dv) with Mbulk as bulk magnetization of iron oxide and g as magnetic shell disorder thickness.

Influence of prey body characteristics and performance on predator selection.

PubMed

Holmes, Thomas H; McCormick, Mark I

2009-03-01

At the time of settlement to the reef environment, coral reef fishes differ in a number of characteristics that may influence their survival during a predatory encounter. This study investigated the selective nature of predation by both a multi-species predator pool, and a single common predator (Pseudochromis fuscus), on the reef fish, Pomacentrus amboinensis. The study focused on the early post-settlement period of P. amboinensis, when mortality, and hence selection, is known to be highest. Correlations between nine different measures of body condition/performance were examined at the time of settlement, in order to elucidate the relationships between different traits. Single-predator (P. fuscus) choice trials were conducted in 57.4-l aquaria with respect to three different prey characteristics [standard length (SL), body weight and burst swimming speed], whilst multi-species trials were conducted on open patch reefs, manipulating prey body weight only. Relationships between the nine measures of condition/performance were generally poor, with the strongest correlations occurring between the morphological measures and within the performance measures. During aquaria trials, P. fuscus was found to be selective with respect to prey SL only, with larger individuals being selected significantly more often. Multi-species predator communities, however, were selective with respect to prey body weight, with heavier individuals being selected significantly more often than their lighter counterparts. Our results suggest that under controlled conditions, body length may be the most important prey characteristic influencing prey survival during predatory encounters with P. fuscus. In such cases, larger prey size may actually be a distinct disadvantage to survival. However, these relationships appear to be more complex under natural conditions, where the expression of prey characteristics, the selectivity fields of a number of different predators, their relative abundance, and the action of external environmental characteristics, may all influence which individuals survive.

Loading capacity and interaction of DNA binding on catanionic vesicles with different cationic surfactants.

PubMed

Xu, Lu; Chen, Jingfei; Feng, Lei; Dong, Shuli; Hao, Jingcheng

2014-12-07

Cationic and anionic (catanionic) vesicles were constructed from the mixtures of sodium laurate (SL) and alkyltrimethylammonium bromide (CnTAB, n = 12, 14, and 16) and were used to control the loading capacity of DNA. The binding saturation point (BSP) of DNA to catanionic vesicles increases with the chain length of cationic surfactants, which is at 1.0, 1.3 and 1.5 for CnTAB with n = 12, 14, and 16, respectively. Our measurements showed that the loading capacity and affinity of DNA can be controlled by catanionic vesicles. It increases with the chain length of cationic surfactants. Because of a large reduction in surface charge density, catanionic vesicles are prone to undergo re-aggregation or fusion with the addition of DNA. DNA molecules can still maintain original coil state during the interaction with catanionic CnTAL vesicles. (1)H NMR data reveals that the obvious dissociation of anionic ions, L(-), from catanionic C14TAL vesicles is due to the interaction with DNA; however, this phenomenon cannot be observed in C12TAB-SL vesicles. Agarose gel electrophoresis (AGE) results demonstrate that the electrostatic interaction between the two oppositely charged cationic and anionic surfactants is stronger than that between DNA and cationic surfactant, CnTAB (n = 12, 14, and 16). Not only is the dissociation of L(-) simply determined by the charge competition, but it also depends largely on the variations in the surface charge density as well as the cationic and anionic surfactant competing ability in geometry configuration of catanionic vesicles. The complicated interaction between DNA and catanionic vesicles induces the deformation of cationic vesicles. Our results should provide clear guidance for choosing more proper vectors for DNA delivery and gene therapy in cell experiments.

Tandem Core–Shell Si–Ta 3N 5 Photoanodes for Photoelectrochemical Water Splitting

DOE PAGES

Narkeviciute, Ieva; Chakthranont, Pongkarn; Mackus, Adriaan J. M.; ...

2016-11-22

Here, nanostructured core–shell Si–Ta 3N 5 photoanodes were designed and synthesized to overcome charge transport limitations of Ta 3N 5 for photoelectrochemical water splitting. The core–shell devices were fabricated by atomic layer deposition of amorphous Ta 2O 5 onto nanostructured Si and subsequent nitridation to crystalline Ta 3N 5. Nanostructuring with a thin shell of Ta 3N 5 results in a 10-fold improvement in photocurrent compared to a planar device of the same thickness. In examining thickness dependence of the Ta 3N 5 shell from 10 to 70 nm, superior photocurrent and absorbed-photon-to-current efficiencies are obtained from the thinner Tamore » 3N 5 shells, indicating minority carrier diffusion lengths on the order of tens of nanometers. The fabrication of a heterostructure based on a semiconducting, n-type Si core produced a tandem photoanode with a photocurrent onset shifted to lower potentials by 200 mV. CoTiO x and NiO x water oxidation cocatalysts were deposited onto the Si–Ta 3N 5 to yield active photoanodes that with NiO x retained 50–60% of their maximum photocurrent after 24 h chronoamperometry experiments and are thus among the most stable Ta 3N 5 photoanodes reported to date.« less

Clustering behavior of hermit crabs (Decapoda, Anomura) in an intertidal rocky shore at São Sebastião, southeastern Brazil.

PubMed

Turra, A; Leite, F P

2000-02-01

The clustering behavior and cluster composition of hermit crabs as well as the patterns of shell utilization of clustered and scattered individuals were studied. This study was conducted in the intertidal region of Grande Beach, São Sebastião, southeastern Brazil. Samples were taken both in randomized transects and 1 m2 quadrats during low tide periods. Crabs were counted, measured (shield length), and sexed. Shells were identified and had their adequacy and condition (physical damage and incrustation) recorded. Clusters occurred mainly in air exposed areas and were dominated or composed only by Clibanarius antillensis. Other species like Paguristes tortugae, Pagurus criniticornis, and Calcinus tibicen were also present in these clusters, but in small numbers. Only one monospecific aggregation composed by individuals of P. criniticornis was recorded in tide pools. Almost all crabs were inactive, despite some that were submerged in tide pools. Most of the individuals of C. antillensis were clustered (70.88%). Scattered individuals were larger than clustered ones and occupied mainly shells of Tegula viridula, which seemed to be the most adequate shell to the crabs. Clustered individuals used less incrusted shells than isolated ones. In general, clustering in Grande Beach presented the same patterns of size and sex distribution, and shell utilization than others already studied, with the exception of the smaller cluster size registered in this area.

Geometrically controlled snapping transitions in shells with curved creases.

PubMed

Bende, Nakul Prabhakar; Evans, Arthur A; Innes-Gold, Sarah; Marin, Luis A; Cohen, Itai; Hayward, Ryan C; Santangelo, Christian D

2015-09-08

Curvature and mechanics are intimately connected for thin materials, and this coupling between geometry and physical properties is readily seen in folded structures from intestinal villi and pollen grains to wrinkled membranes and programmable metamaterials. While the well-known rules and mechanisms behind folding a flat surface have been used to create deployable structures and shape transformable materials, folding of curved shells is still not fundamentally understood. Shells naturally deform by simultaneously bending and stretching, and while this coupling gives them great stability for engineering applications, it makes folding a surface of arbitrary curvature a nontrivial task. Here we discuss the geometry of folding a creased shell, and demonstrate theoretically the conditions under which it may fold smoothly. When these conditions are violated we show, using experiments and simulations, that shells undergo rapid snapping motion to fold from one stable configuration to another. Although material asymmetry is a proven mechanism for creating this bifurcation of stability, for the case of a creased shell, the inherent geometry itself serves as a barrier to folding. We discuss here how two fundamental geometric concepts, creases and curvature, combine to allow rapid transitions from one stable state to another. Independent of material system and length scale, the design rule that we introduce here explains how to generate snapping transitions in arbitrary surfaces, thus facilitating the creation of programmable multistable materials with fast actuation capabilities.

Designing of luminescent GdPO4:Eu@LaPO4@SiO2 core/shell nanorods: Synthesis, structural and luminescence properties

NASA Astrophysics Data System (ADS)

Ansari, Anees A.; Labis, Joselito P.; Aslam Manthrammel, M.

2017-09-01

GdPO4:Eu3+ (core) and GdPO4:Eu@LaPO4 (core/shell) nanorods (NRs) were successfully prepared by urea based co-precipitation process at ambient conditions which was followed by coating with amorphous silica shell via the sol-gel chemical route. The role of surface coating on the crystal structure, crystallinity, morphology, solubility, surface chemistry and luminescence properties were well investigated by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis, Fourier Transform Infrared (FTIR), UV-Vis, and photoluminescence spectroscopy. XRD pattern revealed highly purified, well-crystalline, single phase-hexagonal-rhabdophane structure of GdPO4 crystal. The TEM micrographs exhibited highly crystalline and narrow size distributed rod-shaped GdPO4:Eu3+ nanostructures with average width 14-16 nm and typical length 190-220 nm. FTIR spectra revealed characteristic infrared absorption bands of amorphous silica. High absorbance in a visible region of silica modified core/shell/Si NRs in aqueous environment suggests the high solubility along with colloidal stability. The photoluminescence properties were remarkably enhanced after growth of undoped LaPO4 layers due to the reduction of nonradiative transition rate. The advantages of presented high emission intensity and high solubility of core/shell and core/shell/Si NRs indicated the potential applications in monitoring biological events.

Understanding Bright 13 keV Kr K-shell X-ray Sources at the NIF

NASA Astrophysics Data System (ADS)

May, M. J.; Colvin, J. D.; Kemp, G. E.; Fournier, K. B.; Scott, H.; Patel, M.; Barrios, Widmann; Widmann, K.

2015-11-01

High x-ray conversion efficiency (CE) K-shell Kr sources are being investigated for High Energy Density experiments. These sources are 4.1 mm in diameter 4.4 mm tall hollow epoxy tubes having a 40 μm thick wall holding either 1.2 or 1.5 atm of Kr gas. The CE of K-shell Kr is dependent upon the peak electron temperature in the radiating plasma. In the NIF experiments, the available energy heats the source to Te = 6-7 keV, well below the temperature of Te ~25 keV needed to optimize the Kr CE. The CE is a steep function of the peak electron temperature. A spatially averaged electron temperature can be estimated from measured He(α) and Ly(α) line ratios. Some disagreement has been observed in the simulated and measured line ratios for some of these K-shell sources. Disagreements have been observed between the simulated and measured line ratios for some of these K-shell sources. To help understand this issue, Kr gas pipes have been shot with 3 ω light at ?750 kJ at ~210, ~140 TW and ~120 TW power levels with 3.7, 5.2 and 6.7 ns pulses, respectively. The power and pulse length scaling of the measured CE and K-shell line ratios and their comparison to simulations will be discussed. This work was performed under the auspic

TiO2 -coated fluoride nanoparticles for dental multimodal optical imaging.

PubMed

Braz, Ana K S; Moura, Diógenes S; Gomes, Anderson S L; Ohulchanskyy, Tymish Y; Chen, Guanying; Liu, Maixian; Damasco, Jossana; de Araujo, Renato E; Prasad, Paras N

2018-04-01

Core-shell nanostructures associated with photonics techniques have found innumerous applications in diagnostics and therapy. In this work, we introduce a novel core-shell nanostructure design that serves as a multimodal optical imaging contrast agent for dental adhesion evaluation. This nanostructure consists of a rare-earth-doped (NaYF 4 :Yb 60%, Tm 0.5%)/NaYF 4 particle as the core (hexagonal prism, ~51 nm base side length) and the highly refractive TiO 2 material as the shell (~thickness of 15 nm). We show that the TiO 2 shell provides enhanced contrast for optical coherence tomography (OCT), while the rare-earth-doped core upconverts excitation light from 975 nm to an emission peaked at 800 nm for photoluminescence imaging. The OCT and the photoluminescence wide-field images of human tooth were demonstrated with this nanoparticle core-shell contrast agent. In addition, the described core-shell nanoparticles (CSNps) were dispersed in the primer of a commercially available dental bonding system, allowing clear identification of dental adhesive layers with OCT. We evaluated that the presence of the CSNp in the adhesive induced an enhancement of 67% scattering coefficient to significantly increase the OCT contrast. Moreover, our results highlight that the upconversion photoluminescence in the near-infrared spectrum region is suitable for image of deep dental tissue. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Silica-modified luminescent LaPO4 :Eu@LaPO4 @SiO2 core/shell nanorods: Synthesis, structural and luminescent properties.

PubMed

Ansari, Anees A

2018-02-01

Monoclinic-type tetragonal LaPO 4 :Eu (core) and LaPO 4 :Eu@LaPO 4 (core/shell) nanorods (NRs) were successfully prepared using a urea-based co-precipitation process under ambient conditions. An amorphous silica layer was coated around the luminescent core/shell NRs via the sol-gel process to improve their solubility and colloidal stability in aqueous and non-aqueous media. The prepared nano-products were systematically characterized by X-ray diffraction pattern, transmission electron microscopy, energy dispersive X-ray analysis, and FTIR, UV/Vis, and photoluminescence spectroscopy to examine their phase purity, crystal phase, surface chemistry, solubility and luminescence characteristics. The length and diameter of the nano-products were in the range 80-120 nm and 10-15 nm, respectively. High solubility of the silica-modified core/shell/Si NRs was found for the aqueous medium. The luminescent core NRs exhibited characteristic excitation and emission transitions in the visible region that were greatly affected by surface growth of insulating LaPO 4 and silica layers due to the multiphonon relaxation rate. Our luminescence spectral results clearly show a distinct difference in intensities for core, core/shell, and core/shell/Si NRs. Highly luminescent NRs with good solubility could be useful candidates for a variety of photonic-based biomedical applications. Copyright © 2017 John Wiley & Sons, Ltd.

Photonic jet with ultralong working distance by hemispheric shell.

PubMed

Hengyu, Zhu; Zaichun, Chen; Chong, Chong Tow; Minghui, Hong

2015-03-09

Micro-particle assisted nano-imaging has proven its success in the past few years since it can magnify the nano-objects, especially the metallic objects, into an image then collected by a conventional microscope. Micro-shell, which is a novel design of micro-particle in the configuration of a hemisphere with a hollow core region, is proposed and optimized in this paper in order to obtain a long photonic jet far away from its flat surface, thus increasing its working distance. Its dependence on the configuration and refractive index is investigated numerically. A micro-shell with the outer and inner radii of 5 and 2.5 µm and the refractive index of 1.5 can focus the incident light of 400 nm wavelength 2.7 µm away from the micro-shell flat surface, although the photonic jet intensity decreases to 25.8% compared to the solid hemisphere. Meanwhile, the photonic jet length of the micro-shell under the incident light of 400 nm and 1000 nm wavelengths are 1.7 µm and 4.3 µm, respectively, because its hollow core region tends to reduce the angle variation of the Poynting vectors in the photonic jet. With the long working distance and long photonic jet, the micro-shell could be used to scan over a sample to obtain a large area image when coupled with a conventional microscope, which is especially useful for the samples with the rough surfaces.

Activating glutamate decarboxylase activity by removing the autoinhibitory domain leads to hyper γ-aminobutyric acid (GABA) accumulation in tomato fruit.

PubMed

Takayama, Mariko; Matsukura, Chiaki; Ariizumi, Tohru; Ezura, Hiroshi

2017-01-01

The C-terminal extension region of SlGAD3 is likely involved in autoinhibition, and removing this domain increases GABA levels in tomato fruits. γ-Aminobutyric acid (GABA) is a ubiquitous non-protein amino acid with several health-promoting benefits. In many plants including tomato, GABA is synthesized via decarboxylation of glutamate in a reaction catalyzed by glutamate decarboxylase (GAD), which generally contains a C-terminal autoinhibitory domain. We previously generated transgenic tomato plants in which tomato GAD3 (SlGAD3) was expressed using the 35S promoter/NOS terminator expression cassette (35S-SlGAD3-NOS), yielding a four- to fivefold increase in GABA levels in red-ripe fruits compared to the control. In this study, to further increase GABA accumulation in tomato fruits, we expressed SlGAD3 with (SlGAD3 OX ) or without (SlGAD3ΔC OX ) a putative autoinhibitory domain in tomato using the fruit ripening-specific E8 promoter and the Arabidopsis heat shock protein 18.2 (HSP) terminator. Although the GABA levels in SlGAD3 OX fruits were equivalent to those in 35S-SlGAD3-NOS fruits, GABA levels in SlGAD3ΔC OX fruits increased by 11- to 18-fold compared to control plants, indicating that removing the autoinhibitory domain increases GABA biosynthesis activity. Furthermore, the increased GABA levels were accompanied by a drastic reduction in glutamate and aspartate levels, indicating that enhanced GABA biosynthesis affects amino acid metabolism in ripe-fruits. Moreover, SlGAD3ΔC OX fruits exhibited an orange-ripe phenotype, which was associated with reduced levels of both carotenoid and mRNA transcripts of ethylene-responsive carotenogenic genes, suggesting that over activation of GAD influences ethylene sensitivity. Our strategy utilizing the E8 promoter and HSP terminator expression cassette, together with SlGAD3 C-terminal deletion, would facilitate the production of tomato fruits with increased GABA levels.

Preparing Facilitators From Community-Based Organizations for Evidence-Based Intervention Training in Second Life

PubMed Central

Valladares, Angel Felix; Tschannen, Dana; Villarruel, Antonia Maria

2014-01-01

Background A major barrier to the use and scale-up of evidence-based interventions are challenges related to training and capacity building. A cost-effective and highly interactive multi-user virtual environment, Second Life (SL) is a promising alternative for comprehensive face-to-face facilitator training. Objective The purpose of this study was to examine the feasibility of using SL to train facilitators from community-based organizations to use ¡Cuídate! (Take Care of Yourself), one of the few evidence-based interventions developed and tested with Latino youth to reduce sexual risk behaviors. Methods We recruited 35 participants from community-based organizations throughout the United States to participate in the SL ¡Cuídate! Training of Facilitators. Preparation to use SL consisted of four phases: (1) recruitment and computer capacity screening, (2) enrollment, (3) orientation to the SL program, and (4) technical support throughout the synchronous training sessions. Technical difficulties, the associated cause, and the mitigation strategy implemented were recorded during each session. Participants completed evaluations including perceptions of self-efficacy and confidence to complete the necessary skills to participate in SL training. Results Overall, participants reported high levels of self-efficacy for all skills necessary to participate in SL training. Based on an 11-point scale (0-10), self-efficacy to download and access the software was rated the highest: mean 8.29 (SD 2.19). Interacting with items in SL had the lowest mean score: mean 7.49 (SD 2.89). The majority of technical difficulties experienced by participants were related to inadequate Internet connections or computer malfunctions. Conclusions Our findings support the feasibility of using SL for the ¡Cuídate! Training of Facilitators. The process used in this study to prepare participants to use SL can be used as a basis for other evidence-based intervention training in SL. This study is an important contribution to developing cost-effective and accessible training options for evidence-based interventions. PMID:25270991

Preparing facilitators from community-based organizations for evidence-based intervention training in Second Life.

PubMed

Valladares, Angel Felix; Aebersold, Michelle; Tschannen, Dana; Villarruel, Antonia Maria

2014-09-30

A major barrier to the use and scale-up of evidence-based interventions are challenges related to training and capacity building. A cost-effective and highly interactive multi-user virtual environment, Second Life (SL) is a promising alternative for comprehensive face-to-face facilitator training. The purpose of this study was to examine the feasibility of using SL to train facilitators from community-based organizations to use ¡Cuídate! (Take Care of Yourself), one of the few evidence-based interventions developed and tested with Latino youth to reduce sexual risk behaviors. We recruited 35 participants from community-based organizations throughout the United States to participate in the SL ¡Cuídate! Training of Facilitators. Preparation to use SL consisted of four phases: (1) recruitment and computer capacity screening, (2) enrollment, (3) orientation to the SL program, and (4) technical support throughout the synchronous training sessions. Technical difficulties, the associated cause, and the mitigation strategy implemented were recorded during each session. Participants completed evaluations including perceptions of self-efficacy and confidence to complete the necessary skills to participate in SL training. Overall, participants reported high levels of self-efficacy for all skills necessary to participate in SL training. Based on an 11-point scale (0-10), self-efficacy to download and access the software was rated the highest: mean 8.29 (SD 2.19). Interacting with items in SL had the lowest mean score: mean 7.49 (SD 2.89). The majority of technical difficulties experienced by participants were related to inadequate Internet connections or computer malfunctions. Our findings support the feasibility of using SL for the ¡Cuídate! Training of Facilitators. The process used in this study to prepare participants to use SL can be used as a basis for other evidence-based intervention training in SL. This study is an important contribution to developing cost-effective and accessible training options for evidence-based interventions.

Epitaxial regrowth of silicon for the fabrication of radial junction nanowire solar cells

NASA Astrophysics Data System (ADS)

Kendrick, Chito E.; Eichfeld, Sarah M.; Ke, Yue; Weng, Xiaojun; Wang, Xin; Mayer, Theresa S.; Redwing, Joan M.

2010-08-01

Radial p-n silicon nanowire (SiNW) solar cells are of interest as a potential pathway to increase the efficiency of crystalline silicon photovoltaics by reducing the junction length and surface reflectivity. Our studies have focused on the use of vapor-liquid-solid (VLS) growth in combination with chemical vapor deposition (CVD) processing for the fabrication of radial p-n junction SiNW array solar cells. High aspect ratio p-type SiNW arrays were initially grown on gold-coated (111) Si substrates by CVD using SiCl4 as the source gas and B2H6 as the p-type dopant source. The epitaxial re-growth of n-type Si shell layers on the Si nanowires was then investigated using SiH4 as the source gas and PH3 as the dopant. Highly conformal coatings were achieved on nanowires up to 25 μm in length. The microstructure of the Si shell layer changed from polycrystalline to single crystal as the deposition temperature was raised from 650oC to 950oC. Electrical test structures were fabricated by aligning released SiNWs onto pre-patterned substrates via fieldassisted assembly followed by selective removal of the n-type shell layer and contact deposition. Current-voltage measurements of the radial p-n SiNWs diodes fabricated with re-grown Si shell layers at 950°C demonstrate rectifying behavior with an ideality factor of 1.93. Under illumination from an AM1.5g spectrum and efficiency for this single SiNW radial p-n junction was determined to be 1.8%, total wire diameter was 985 nm.

Predicting human genetic interactions from cancer genome evolution.

PubMed

Lu, Xiaowen; Megchelenbrink, Wout; Notebaart, Richard A; Huynen, Martijn A

2015-01-01

Synthetic Lethal (SL) genetic interactions play a key role in various types of biological research, ranging from understanding genotype-phenotype relationships to identifying drug-targets against cancer. Despite recent advances in empirical measuring SL interactions in human cells, the human genetic interaction map is far from complete. Here, we present a novel approach to predict this map by exploiting patterns in cancer genome evolution. First, we show that empirically determined SL interactions are reflected in various gene presence, absence, and duplication patterns in hundreds of cancer genomes. The most evident pattern that we discovered is that when one member of an SL interaction gene pair is lost, the other gene tends not to be lost, i.e. the absence of co-loss. This observation is in line with expectation, because the loss of an SL interacting pair will be lethal to the cancer cell. SL interactions are also reflected in gene expression profiles, such as an under representation of cases where the genes in an SL pair are both under expressed, and an over representation of cases where one gene of an SL pair is under expressed, while the other one is over expressed. We integrated the various previously unknown cancer genome patterns and the gene expression patterns into a computational model to identify SL pairs. This simple, genome-wide model achieves a high prediction power (AUC = 0.75) for known genetic interactions. It allows us to present for the first time a comprehensive genome-wide list of SL interactions with a high estimated prediction precision, covering up to 591,000 gene pairs. This unique list can potentially be used in various application areas ranging from biotechnology to medical genetics.

Uncovering the Anthropogenic Sea Level Change using an Improved Sea Level Reconstruction for the Indian Ocean

NASA Astrophysics Data System (ADS)

Kumar, P.; Hamlington, B.; Thompson, P. R.; Han, W.

2016-12-01

Despite having some of the world's most densely populated and vulnerable coastal regions, sea level (SL) variability in the Indian Ocean (IO) has received considerably less attention than the Pacific Ocean. Differentiating the internal variability from the long-term trend in global mean sea level (GMSL) at decadal time-scales is vital for planning and mitigation efforts in the IO region. Understanding the dynamics of internal and anthropogenic SL change is essential for understanding the dynamic pathways that link the IO basin to terrestrial climates world-wide. With a sparse pre-satellite observational record of the IO, the Indo-Pacific internal climate variability is difficult to represent accurately. However, an improved representation of pre-satellite SL variability can be achieved by using a multivariate reconstruction technique. By using cyclostationary empirical orthogonal functions (CSEOFs) that can capture time-varying spatial patterns, gaps in the historical record when observations are sparse are filled using spatial relationships from time periods when the observational network is dense. This reconstruction method combines SL data and sea surface temperature (SST) to create a SL reconstruction that spans a period from 1900 to present, long enough to study climate signals over interannual to decadal time scales. This study aims at estimating the component of SL rise that relates to anthropogenic forcing by identifying and removing the fraction related to internal variability. An improved understanding of how the internal climate variability can affect the IO SL trend and variability, will provide an insight into the future SL changes. It is also important to study links between SL and climate variability in the past to understand how SL will respond to similar climatic events in the future and if this response will be influenced by the changing climate.

MRI Near Metallic Implants Using MAVRIC SL: Initial Clinical Experience at 3T

PubMed Central

Gutierrez, Luis B.; Do, Bao H.; Gold, Garry E.; Hargreaves, Brian A.; Koch, Kevin M.; Worters, Pauline W.; Stevens, Kathryn J.

2014-01-01

Rationale and Objectives To compare the effectiveness of MAVRIC SL with conventional 2D-FSE MR techniques at 3T in imaging patients with a variety of metallic implants. Materials and Methods Twenty-one 3T MR studies were obtained in 19 patients with different types of metal implants. Paired MAVRIC SL and 2D-FSE sequences were reviewed by 2 radiologists, and compared for in-plane and through-plane metal artifact, visualization of the bone implant interface and surrounding soft tissues, blurring, and overall image quality using a 2-tailed Wilcoxon signed rank test. The area of artifact on paired images was measured and compared using a paired Wilcoxon signed rank test. Changes in patient management resulting from MAVRIC SL imaging were documented. Results Significantly less in-plane and through-plane artifact was seen with MAVRIC SL, with improved visualization of the bone-implant interface and surrounding soft tissues, and superior overall image quality (p = 0.0001). Increased blurring was seen with MAVRIC SL (p=0.0016). MAVRIC SL significantly decreased the image artifact compared to 2D-FSE (p=0.0001). Inclusion of MAVRIC SL to the imaging protocol determined the need for surgery or type of surgery in 5 patients, and ruled out the need for surgery in 13 patients. In 3 patients the area of interest was well seen on both MAVRIC SL and 2D-FSE images, so the addition of MAVRIC had no effect on patient management. Conclusion Imaging around metal implants with MAVRIC SL at 3T significantly improved image quality and decreased image artifact compared to conventional 2D-FSE imaging techniques, and directly impacted patient management. PMID:25435186

MR imaging near metallic implants using MAVRIC SL: initial clinical experience at 3T.

PubMed

Gutierrez, Luis B; Do, Bao H; Gold, Garry E; Hargreaves, Brian A; Koch, Kevin M; Worters, Pauline W; Stevens, Kathryn J

2015-03-01

To compare the effectiveness of multiacquisition with variable resonance image combination selective (MAVRIC SL) with conventional two-dimensional fast spin-echo (2D-FSE) magnetic resonance (MR) techniques at 3T in imaging patients with a variety of metallic implants. Twenty-one 3T MR studies were obtained in 19 patients with different types of metal implants. Paired MAVRIC SL and 2D-FSE sequences were reviewed by two radiologists and compared for in-plane and through-plane metal artifact, visualization of the bone implant interface and surrounding soft tissues, blurring, and overall image quality using a two-tailed Wilcoxon signed rank test. The area of artifact on paired images was measured and compared using a paired Wilcoxon signed rank test. Changes in patient management resulting from MAVRIC SL imaging were documented. Significantly less in-plane and through-plane artifact was seen with MAVRIC SL, with improved visualization of the bone-implant interface and surrounding soft tissues, and superior overall image quality (P = .0001). Increased blurring was seen with MAVRIC SL (P = .0016). MAVRIC SL significantly decreased the image artifact compared to 2D-FSE (P = .0001). Inclusion of MAVRIC SL to the imaging protocol determined the need for surgery or type of surgery in five patients and ruled out the need for surgery in 13 patients. In three patients, the area of interest was well seen on both MAVRIC SL and 2D-FSE images, so the addition of MAVRIC had no effect on patient management. Imaging around metal implants with MAVRIC SL at 3T significantly improved image quality and decreased image artifact compared to conventional 2D-FSE imaging techniques and directly impacted patient management. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

SL-401 and SL-501, Targeted Therapeutics Directed at the Interleukin-3 Receptor, Inhibit the Growth of Leukaemic Cells and Stem Cells in Advanced Phase Chronic Myeloid Leukaemia

PubMed Central

Frolova, Olga; Benito, Juliana; Brooks, Chris; Wang, Rui-Yu; Korchin, Borys; Rowinsky, Eric K.; Cortes, Jorge; Kantarjian, Hagop; Andreeff, Michael; Frankel, Arthur E.; Konopleva, Marina

2014-01-01

SUMMARY While imatinib and other tyrosine kinase inhibitors (TKIs) are highly efficacious in the treatment of chronic myeloid leukaemia (CML), some patients become refractory to these therapies. After confirming that interleukin-3 receptor (IL3R, CD123) is highly expressed on CD34+/CD38− BCR-ABL1+ CML stem cells, we investigated whether targeting IL3R with diphtheria toxin (DT)-IL3 fusion proteins SL-401 (DT388-IL3) and SL-501 (DT388-IL3[K116W]) could eradicate these stem cells. SL-401 and SL-501 inhibited cell growth and induced apoptosis in the KBM5 cell line and its TKI-resistant KBM5-STI subline. Combinations of imatinib with these agents increased apoptosis in KBM5 and in primary CML cells. In six primary CML samples, including CML cells harbouring the ABL1 T315I mutation, SL-401 and SL-501 decreased the absolute numbers of viable CD34+/CD38−/CD123+ CML progenitor cells by inducing apoptosis. IL3-targeting agents reduced clonogenic growth and diminished the fraction of primitive long-term culture-initiating cells in samples from patients with advanced phase CML that were resistant to TKIs or harboured an ABL1 mutation. Survival was also extended in a mouse model of primary TKI-resistant CML blast crisis. These data suggest that the DT-IL3 fusion proteins, SL-401 and SL-501, deplete CML stem cells and may increase the effectiveness of current CML treatment, which principally targets tumour bulk. PMID:24942980

SL-401 and SL-501, targeted therapeutics directed at the interleukin-3 receptor, inhibit the growth of leukaemic cells and stem cells in advanced phase chronic myeloid leukaemia.

PubMed

Frolova, Olga; Benito, Juliana; Brooks, Chris; Wang, Rui-Yu; Korchin, Borys; Rowinsky, Eric K; Cortes, Jorge; Kantarjian, Hagop; Andreeff, Michael; Frankel, Arthur E; Konopleva, Marina

2014-09-01

While imatinib and other tyrosine kinase inhibitors (TKIs) are highly efficacious in the treatment of chronic myeloid leukaemia (CML), some patients become refractory to these therapies. After confirming that interleukin-3 receptor (IL3R, CD123) is highly expressed on CD34(+) /CD38(-) BCR-ABL1(+) CML stem cells, we investigated whether targeting IL3R with diphtheria toxin (DT)-IL3 fusion proteins SL-401 (DT388 -IL3) and SL-501 (DT388 -IL3[K116W]) could eradicate these stem cells. SL-401 and SL-501 inhibited cell growth and induced apoptosis in the KBM5 cell line and its TKI-resistant KBM5-STI subline. Combinations of imatinib with these agents increased apoptosis in KBM5 and in primary CML cells. In six primary CML samples, including CML cells harbouring the ABL1 T315I mutation, SL-401 and SL-501 decreased the absolute numbers of viable CD34(+) /CD38(-) /CD123(+) CML progenitor cells by inducing apoptosis. IL3-targeting agents reduced clonogenic growth and diminished the fraction of primitive long-term culture-initiating cells in samples from patients with advanced phase CML that were resistant to TKIs or harboured an ABL1 mutation. Survival was also extended in a mouse model of primary TKI-resistant CML blast crisis. These data suggest that the DT-IL3 fusion proteins, SL-401 and SL-501, deplete CML stem cells and may increase the effectiveness of current CML treatment, which principally targets tumour bulk. © 2014 John Wiley & Sons Ltd.

Anterior Chamber Angle Measurements Using Schwalbe's Line with High Resolution Fourier-Domain Optical Coherence Tomography

PubMed Central

Qin, Bing; Francis, Brian A.; Li, Yan; Tang, Maolong; Zhang, Xinbo; Jiang, Chunhui; Cleary, Catherine; Huang, David

2012-01-01

Purpose To use Fourier-domain optical coherence tomography (OCT) to measure the angle opening distance at Schwalbe's line (AOD-SL) and determine its value in anterior chamber angle assessment. Methods Horizontal scans of the nasal and temporal anterior chamber angles in glaucoma subjects were performed by 830 nm wavelength Fourier-domain OCT. Images were graded by two ophthalmologists who assessed the visibility of Schwalbe’s line (SL), anterior limbus (AL), scleral spur (SS), and angle recess (AR). AOD-SL was measured with computer calipers. SL was manually identified by the termination of the corneal endothelium. Gonioscopy was used to classify anterior chamber angles according to a modified Shaffer system. Spearman's rho analysis was performed to assess correlation between AOD-SL and modified Shaffer grade. A cut-off value of AOD-SL for diagnosing occludable angles (modified Shaffer grade ≤1) was determined by receiver operating characteristic (ROC) analyses. Results Thirty-five glaucoma subjects (65 eyes) were enrolled. SL, AL, AR, and SS were visible by OCT in 97.7%, 99.2%, 87.3%, and 80.8% of eyes, respectively. Nasal and temporal AOD-SLs were 322.6 ± 200.2 µm and 341.4 ± 197.4 µm, respectively. Correlation coefficients between AOD-SL and modified Shaffer grade were 0.80 (nasal) and 0.81 (temporal). The diagnostic cut-off value of AOD-SL for occludable angles was 290 µm. The areas under the ROC curve, sensitivity, specificity values were 0.90, 0.80, 0.87 (nasal) and 0.90, 0.85, 0.77 (temporal). Conclusions The measurement of AOD-SL by Fourier-domain OCT is highly correlated with gonioscopy and may be a useful noncontact method of assessing angle closure risk. PMID:22827999

cDNA cloning and isolation of somatolactin in Mozambique tilapia and effects of seawater acclimation, confinement stress, and fasting on its pituitary expression.

PubMed

Uchida, Katsuhisa; Moriyama, Shunsuke; Breves, Jason P; Fox, Bradley K; Pierce, Andrew L; Borski, Russell J; Hirano, Tetsuya; Grau, E Gordon

2009-04-01

Somatolactin (SL) is a member of the growth hormone (GH)/prolactin (PRL) family of pituitary hormones, and is found in a variety of teleost species. Somatolactin is thought to be involved in a wide range of physiological actions, including reproduction, stress response, the regulation of Ca(2+) and acid-base balance, growth, metabolism, and immune response. We report here on the cDNA structure of SL from the pituitary of Mozambique tilapia, Oreochromis mossambicus, and its gene expression in response to seawater acclimation, stress, and fasting. Tilapia SL cDNA (1573bp long) encoded a prehormone of 230 amino acids. Sequence analysis of purified SL revealed that the prehormone is composed of a signal peptide of 23 amino acids and a mature protein of 207 amino acids, which has a possible N-glycosylation site at position 121 and seven Cys residues. Tilapia SL shows over 80% amino acid identity with SLalpha of advanced teleosts such as medaka and flounder, and around 50% identity with SLbeta of carp and goldfish. Acclimation to seawater had no effect on pituitary expression of SL or on hepatic expression of the putative tilapia SL receptor (GHR1). By contrast, seawater acclimation resulted in significant increases in pituitary GH expression and in hepatic expression of tilapia GH receptor (GHR2). Confinement stress had no effect on pituitary expression of either SL or GH, or on hepatic expression of GHR1, whereas a significant increase was seen in GHR2 expression in the liver. Fasting for 4 weeks resulted in significant reductions in SL transcripts both in fresh water and seawater. It is highly likely that SL is involved in metabolic processes in tilapia along with the GH/IGF-I axis.

Genome-wide analysis of the fructose 1,6-bisphosphate aldolase (FBA) gene family and functional characterization of FBA7 in tomato.

PubMed

Cai, Bingbing; Li, Qiang; Xu, Yongchao; Yang, Long; Bi, Huangai; Ai, Xizhen

2016-11-01

Fructose 1,6-bisphosphate aldolase (FBA) is a key enzyme in plants that is involved in glycolysis, gluconeogenesis, and the Calvin cycle. FBA genes play significant roles in biotic and abiotic stress responses and also regulate growth and development. Despite the importance of FBA genes, little is known about it in tomato. In this study, we identified 8 FBA genes in tomato and classified them into 2 subgroups based on a phylogenetic tree, gene structures, and conserved motifs. Five (SlFBA1, 2, 3, 4 and 5) and three (SlFBA6, 7, and 8) SlFBA proteins were predicted to be localized in chloroplasts and cytoplasm, respectively. The phylogenetic analysis of FBAs from tomato, Arabidopsis, rice, and other organisms suggested that SlFBA shared the highest protein homology with FBAs from other plants. Synteny analysis indicated that segmental duplication events contributed to the expansion of the tomato FBA family. The expression profiles revealed that all SlFBAs were involved in the response to low and high temperature stresses. SlFBA7 overexpression increased the expression and activities of other main enzymes in Calvin cycle, net photosynthetic rate (Pn), seed size and stem diameter. SlFBA7 overexpression enhanced tolerances in seed germination under suboptimal temperature stresses. Taken together, comprehensive analyses of SlFBAs would provide a basis for understanding of evolution and function of SlFBA family. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

An in vivo genetic screen for genes involved in spliced leader trans-splicing indicates a crucial role for continuous de novo spliced leader RNP assembly.

PubMed

Philippe, Lucas; Pandarakalam, George C; Fasimoye, Rotimi; Harrison, Neale; Connolly, Bernadette; Pettitt, Jonathan; Müller, Berndt

2017-08-21

Spliced leader (SL) trans-splicing is a critical element of gene expression in a number of eukaryotic groups. This process is arguably best understood in nematodes, where biochemical and molecular studies in Caenorhabditis elegans and Ascaris suum have identified key steps and factors involved. Despite this, the precise details of SL trans-splicing have yet to be elucidated. In part, this is because the systematic identification of the molecules involved has not previously been possible due to the lack of a specific phenotype associated with defects in this process. We present here a novel GFP-based reporter assay that can monitor SL1 trans-splicing in living C. elegans. Using this assay, we have identified mutants in sna-1 that are defective in SL trans-splicing, and demonstrate that reducing function of SNA-1, SNA-2 and SUT-1, proteins that associate with SL1 RNA and related SmY RNAs, impairs SL trans-splicing. We further demonstrate that the Sm proteins and pICln, SMN and Gemin5, which are involved in small nuclear ribonucleoprotein assembly, have an important role in SL trans-splicing. Taken together these results provide the first in vivo evidence for proteins involved in SL trans-splicing, and indicate that continuous replacement of SL ribonucleoproteins consumed during trans-splicing reactions is essential for effective trans-splicing. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Functional ET(A)-ET(B) Receptor Cross-talk in Basilar Artery In Situ From ET(B) Receptor Deficient Rats.

PubMed

Yoon, SeongHun; Gariepy, Cheryl E; Yanagisawa, Masashi; Zuccarello, Mario; Rapoport, Robert M

2016-03-01

The role of endothelin (ET)(A)-ET(B) receptor cross-talk in limiting the ET(A) receptor antagonist inhibition of ET-1 constriction is revealed by the partial or complete dependency of the ET(A) receptor antagonist inhibition on functional removal of the ET(B) receptor. Although functional removal of the ET(B) receptor is generally accomplished with ET(B) receptor antagonist, a novel approach using rats containing a naturally occurring deletion mutation in the ET(B) receptor [rescued "spotting lethal" (sl) rats; ET(B)(sl/sl)] demonstrated increased ET(A) receptor antagonist inhibition of ET-1 constriction in vena cava. We investigated whether this deletion mutation was also sufficient to remove the ET(B) receptor dependency of the ET(A) receptor antagonist inhibition of ET-1 constriction in the basilar artery. Consistent with previous reports, ET-1 plasma levels were elevated in ET(B)(sl/sl) as compared with ET(B)(+/+) rats. ET(B) receptor antagonist failed to relax the ET-1 constricted basilar artery from ET(B)(+/+) and ET(B)(sl/sl) rats. Relaxation to combined ET(A) and ET(B) receptor antagonist was greater than relaxation to ET(A) receptor antagonist in the basilar artery from ET(B)(+/+) and, unexpectedly, ET(B)(sl/sl) rats. These findings confirm the presence of ET(A)-ET(B) receptor cross-talk in the basilar artery. We speculate that mutant ET(B) receptor expression produced by alternative splicing may be sufficient to allow cross-talk.

Spawn in two deep-sea volute gastropods (Neogastropoda: Volutidae) from southwestern Atlantic waters

NASA Astrophysics Data System (ADS)

Penchaszadeh, Pablo E.; Teso, Valeria; Pastorino, Guido

2017-12-01

The gastropods Odontocymbiola pescalia and Provocator corderoi and their egg capsules were collected by the R/V Puerto Deseado from the Mar del Plata Submarine Canyon ( 37°53‧S, at depths of 291-1404 m) and from Burdwood Bank ( 54°27‧S, 128-785 m). Odontocymbiola pescalia egg capsules measured 15.67 ± 3.38 mm in diameter. They were subspherical in shape with an external calcareous layer. Each egg capsule contained 3-5 embryos and white material as extra embryonic food. Embryos grew to a size of up to 9.3 ± 1.1 mm in mean shell length before hatching as crawling juveniles. The spawn of P. corderoi consisted of a single dome shaped egg capsule of 14.17 ± 1.5 mm in diameter, attached to hard substrata by a basal membrane with a rounded outline. A curved semilunar furrow (seam) on one side of the capsules was always present. The number of embryos per capsule was 2-6. Embryos hatched as crawling juveniles with a shell length of 5.9 ± 0.6 mm. The size and number of whorls in the hatchling shell suggested a slow rate of development, akin to many other deep-sea invertebrates. The egg capsules and reproductive development strategies of both species were compared with those from other congeneric representatives.

Low temperature grown ZnO@TiO{sub 2} core shell nanorod arrays for dye sensitized solar cell application

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

Goh, Gregory Kia Liang; Le, Hong Quang, E-mail: lehq@imre.a-star.edu.sg; Huang, Tang Jiao

High aspect ratio ZnO nanorod arrays were synthesized on fluorine-doped tin oxide glasses via a low temperature solution method. By adjusting the growth condition and adding polyethylenimine, ZnO nanorod arrays with tunable length were successfully achieved. The ZnO@TiO{sub 2} core shells structures were realized by a fast growth method of immersion into a (NH{sub 4}){sub 2}·TiF{sub 6} solution. Transmission electron microscopy, X-ray Diffraction and energy dispersive X-ray measurements all confirmed the existence of a titania shell uniformly covering the ZnO nanorod's surface. Results of solar cell testing showed that addition of a TiO{sub 2} shell to the ZnO nanorod significantlymore » increased short circuit current (from 4.2 to 5.2 mA/cm{sup 2}), open circuit voltage (from 0.6 V to 0.8 V) and fill factor (from 42.8% to 73.02%). The overall cell efficiency jumped from 1.1% for bare ZnO nanorod to 3.03% for a ZnO@TiO{sub 2} core shell structured solar cell with a 18–22 nm shell thickness, a nearly threefold increase. - Graphical abstract: The synthesis process of coating TiO{sub 2} shell onto ZnO nanorod core is shown schematically. A thin, uniform, and conformal shell had been grown on the surface of the ZnO core after immersing in the (NH{sub 4}){sub 2}·TiF{sub 6} solution for 5–15 min. - Highlights: • ZnO@TiO{sub 2} core shell nanorod has been grown on FTO substrate using low temperature solution method. • TEM, XRD, EDX results confirmed the existing of titana shell, uniformly covered rod's surface. • TiO{sub 2} shell suppressed recombination, demonstrated significant enhancement in cell's efficiency. • Core shell DSSC's efficiency achieved as high as 3.03%, 3 times higher than that of ZnO nanorods.« less

134. ARAII SL1 decontamination and lay down building (ARA614) erected ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

134. ARA-II SL-1 decontamination and lay down building (ARA-614) erected after accidental explosion of SL-1 reactor. Shows vicinity map, index of related drawings, plot plan and other detail. F.C. Torkelson Company 842-area/SL-1-101-U-2. Date: September 1962. Ineel index code no. 070-0101-65-851-150713. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

Follicular delivery of spironolactone via nanostructured lipid carriers for management of alopecia.

PubMed

Shamma, Rehab Nabil; Aburahma, Mona Hassan

2014-01-01

Spironolactone (SL) is a US Food and Drug Administration-approved drug for the treatment of hypertension and various edematous conditions. SL has gained a lot of attention for treating androgenic alopecia due to its potent antiandrogenic properties. Recently, there has been growing interest for follicular targeting of drug molecules for treatment of hair and scalp disorders using nanocolloidal lipid-based delivery systems to minimize unnecessary systemic side effects associated with oral drug administration. Accordingly, the objective of this study is to improve SL efficiency and safety in treating alopecia through the preparation of colloidal nanostructured lipid carriers (NLCs) for follicular drug delivery. SL-loaded NLCs were prepared by an emulsion solvent diffusion and evaporation method using 23 full factorial design. All of the prepared formulations were spherical in shape with nanometric size range (215.6-834.3 nm) and entrapment efficiency >74%. Differential scanning calorimetry thermograms and X-ray diffractograms revealed that SL exists in amorphous form within the NLC matrices. The drug release behavior from the NLCs displayed an initial burst release phase followed by sustained release of SL. Confocal laser scanning microscopy confirmed the potential of delivering the fluorolabeled NLCs within the follicles, suggesting the possibility of using SL-loaded NLCs for localized delivery of SL into the scalp hair follicles.

Follicular delivery of spironolactone via nanostructured lipid carriers for management of alopecia

PubMed Central

Shamma, Rehab Nabil; Aburahma, Mona Hassan

2014-01-01

Spironolactone (SL) is a US Food and Drug Administration-approved drug for the treatment of hypertension and various edematous conditions. SL has gained a lot of attention for treating androgenic alopecia due to its potent antiandrogenic properties. Recently, there has been growing interest for follicular targeting of drug molecules for treatment of hair and scalp disorders using nanocolloidal lipid-based delivery systems to minimize unnecessary systemic side effects associated with oral drug administration. Accordingly, the objective of this study is to improve SL efficiency and safety in treating alopecia through the preparation of colloidal nanostructured lipid carriers (NLCs) for follicular drug delivery. SL-loaded NLCs were prepared by an emulsion solvent diffusion and evaporation method using 23 full factorial design. All of the prepared formulations were spherical in shape with nanometric size range (215.6–834.3 nm) and entrapment efficiency >74%. Differential scanning calorimetry thermograms and X-ray diffractograms revealed that SL exists in amorphous form within the NLC matrices. The drug release behavior from the NLCs displayed an initial burst release phase followed by sustained release of SL. Confocal laser scanning microscopy confirmed the potential of delivering the fluorolabeled NLCs within the follicles, suggesting the possibility of using SL-loaded NLCs for localized delivery of SL into the scalp hair follicles. PMID:25473283

Gd(III)-DOTA-modified sonosensitive liposomes for ultrasound-triggered release and MR imaging

NASA Astrophysics Data System (ADS)

Jung, Suk Hyun; Na, Kyunga; Lee, Seul A.; Cho, Sun Hang; Seong, Hasoo; Shin, Byung Cheol

2012-08-01

Ultrasound-sensitive (sonosensitive) liposomes for tumor targeting have been studied in order to increase the antitumor efficacy of drugs and decrease the associated severe side effects. Liposomal contrast agents having Gd(III) are known as a nano-contrast agent system for the efficient and selective delivery of contrast agents into pathological sites. The objective of this study was to prepare Gd(III)-DOTA-modified sonosensitive liposomes (GdSL), which could deliver a model drug, doxorubicin (DOX), to a specific site and, at the same time, be capable of magnetic resonance (MR) imaging. The GdSL was prepared using synthesized Gd(III)-DOTA-1,2-distearoyl- sn-glycero-3-phosphoethanolamine lipid. Sonosensitivity of GdSL to 20-kHz ultrasound induced 33% to 40% of DOX release. The relaxivities ( r 1) of GdSL were 6.6 to 7.8 mM-1 s-1, which were higher than that of MR-bester®. Intracellular uptake properties of GdSL were evaluated according to the intensity of ultrasound. Intracellular uptake of DOX for ultrasound-triggered GdSL was higher than that for non-ultrasound-triggered GdSL. The results of our study suggest that the paramagnetic and sonosensitive liposomes, GdSL, may provide a versatile platform for molecular imaging and targeted drug delivery.

Isolation and cDNA cloning of a novel red colour-related pigment-binding protein derived from the shell of the shrimp, Litopenaeus vannamei.

PubMed

Pan, Chuang; Ishizaki, Shoichiro; Nagashima, Yuji; Gao, Jialong; Watabe, Shugo

2018-02-15

Pigment-binding proteins play important roles in crustacean shell colour change. In this study, a red colour-related pigment-binding protein, designated LvPBP75, was purified from the shell of Litopenaeus vannamei. HPLC and PAGE analysis showed that LvPBP75 was a homogeneous monomer with molecular mass of 75kDa. Peptide mass fingerprint analysis revealed that LvPBP75 belonged to hemocyanin, and the released pigment from heated LvPBP75 showed a λ max at 481nm in acetone. The significant red-colour change temperatures were detected at 30 and 80°C, respectively. Based on the determined amino acid fragments, a full-length cDNA of LvPBP75 was cloned and sequenced. The ORF encodes a protein of 662 amino acids having 80% identity with penaeidae hemocyanin. These results strongly suggest a novel function of hemocyanin, namely binding with pigment, and its involvement in L. vannamei shell colour change. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hydrazine-Assisted Formation of Indium Phosphide (InP)-Based Nanowires and Core-Shell Composites

PubMed Central

Patzke, Greta R.; Kontic, Roman; Shiolashvili, Zeinab; Makhatadze, Nino; Jishiashvili, David

2012-01-01

Indium phosphide nanowires (InP NWs) are accessible at 440 °C from a novel vapor phase deposition approach from crystalline InP sources in hydrazine atmospheres containing 3 mol % H2O. Uniform zinc blende (ZB) InP NWs with diameters around 20 nm and lengths up to several tens of micrometers are preferably deposited on Si substrates. InP particle sizes further increase with the deposition temperature. The straightforward protocol was extended on the one-step formation of new core-shell InP–Ga NWs from mixed InP/Ga source materials. Composite nanocables with diameters below 20 nm and shells of amorphous gallium oxide are obtained at low deposition temperatures around 350 °C. Furthermore, InP/Zn sources afford InP NWs with amorphous Zn/P/O-coatings at slightly higher temperatures (400 °C) from analogous setups. At 450 °C, the smooth outer layer of InP-Zn NWs is transformed into bead-shaped coatings. The novel combinations of the key semiconductor InP with isotropic insulator shell materials open up interesting application perspectives in nanoelectronics. PMID:28809296

Study of the microstructure and mechanical properties of white clam shell.

PubMed

Liang, Yunhong; Zhao, Qian; Li, Xiujuan; Zhang, Zhihui; Ren, Luquan

2016-08-01

The microstructure and mechanical properties of white clam shell were investigated, respectively. It can be divided into horny layer, prismatic layer and nacreous layer. Crossed-lamellar structure was the microstructural characteristic. The extension direction of lamellae in prismatic layer was different from that in nacreous layer, which formed an angle on the interface between prismatic layer and nacreous layer. The phase component of three layers was CaCO3 with crystallization morphology of aragonite, which confirmed the crossed-lamellar structural characteristic. White calm shell exhibited perfect mechanical properties. The microhardness values of three layers were 273HV, 240HV and 300HV, respectively. The average values of flexure and compression strength were 110.2MPa and 80.1MPa, respectively. The macroscopical cracks crossed the lamellae and finally terminated within the length range of about 80μm. It was the microstructure characteristics, the angle on the interface between prismatic and nacreous layer and the hardness diversity among the different layers that enhanced mechanical properties of white calm shell. Copyright © 2016 Elsevier Ltd. All rights reserved.