bluuebunny/crossref_metadata_2025_split huggingface dataset:
Projectively flat Finsler manifolds with infinite dimensional holonomy
Authors: Muzsnay Zoltán , Nagy Péter T. 
Published: January 2013

Abstract
Recently, we developed a method for the study of holonomy properties of
non-Riemannian Finsler manifolds and obtained that the holonomy group cannot be a compact Lie group if the Finsler manifold of dimension >2 has non-zero constant flag curvature. The purpose of this paper is to move
further, exploring the holonomy properties of projectively flat Finsler
manifolds of non-zero constant flag curvature. We prove in particular that
projectively flat Randers and Bryant–Shen manifolds of non-zero constant
flag curvature have infinite dimensional holonomy group.
On the subconvexity problem for GL(3) × GL(2) L-functions
Authors: Khan Rizwanur 
Published: January 2013

Abstract
Fix g a self-dual Hecke–Maass form for SL3(ℤ). Let f be a holomorphic newform of prime level q and fixed weight. Conditional on a lower bound for a short sum of squares of Fourier coefficients of f, we prove a subconvexity bound in the q aspect for L(s,g×f) at the central point.
On hypersurfaces containing projective varieties
Authors: Park Euisung 
Published: January 2013

Abstract
Classical Castelnuovo's lemma shows that the number of linearly independent quadratic equations of a nondegenerate irreducible projective variety of codimension c is at most

c
+
1

2

${{\binom{c+1}{2}}}$

and the equality is attained if and only if the variety is of minimal degree. Also a generalization of Castelnuovo's lemma by G. Fano implies that the next case occurs if and only if the variety is a del Pezzo variety. For curve case, these results are extended to equations of arbitrary degree respectively by J. Harris and S. L'vovsky. This paper is intended to extend these results to arbitrary dimensional varieties and to the next cases.
A simple and efficient procedure for synthesis of symmetrical bis(4-amino-4H-1,2,4-triazole-5-thiols)
Authors: Ebrahimi Sattar 
Published: January 2013

Abstract
A series of bis(1,2,4-triazole-3-thiols) 3a–d were prepared by condensation reactions of arylbis(carboxymethylthio)methanes 2a–d with thiocarbohydrazide. The starting diacids 2a–d were prepared by reactions of aromatic aldehydes 1a–d with thioglycolic acid. The structures of these newly synthesized compounds are characterized by elemental analysis, IR, and NMR spectroscopy.
Microcompartments in the Drosophila heart and the mammalian brain: general features and common principles
Authors: Brandt Roland , Paululat Achim 
Published: January 2013

Abstract
Microcompartments are sub-organellar functional units and may have an important role in cellular physiology. They can act as highly dynamic or even transiently forming organizing compartments within cells. In this review, we would like to extend the concept of microcompartments as subcellular structures in individual cells in a way that it includes specializations that occur between different cells and between cells and components of the extracellular matrix. To develop the general features and properties of these structures, we will present two quite different examples – the development and maturation of the Drosophila heart and the dynamics of synaptic contacts in the mammalian brain. We argue that the molecular architecture, the function and the maintenance of these specializations follows common principles independent of the organ or the organism under investigation. They fulfill the criteria for being proper microcompartments, including their function as local units for the segregation of responses, their ability to serve as organizing platforms in a temporally and spatially highly restricted manner, and their regulation through instructions from neighboring cells or extracellular matrix components in a locally restricted and autonomous manner.
Prenatal care in adult women exposed to childhood sexual abuse
Authors: Leeners Brigitte , Stiller Ruth , Block Emina , Görres Gisela , Rath Werner , Tschudin Sibil 
Published: January 2013

Abstract

Aims: Several case reports show a negative impact of childhood sexual abuse (CSA) on prenatal care. The study aimed to systematically investigate this association in a larger study group.

Methods: CSA was investigated by face-to-face interviews and by a modified questionnaire developed by Wyatt. All study participants completed a self-administered questionnaire designed to investigate the consequences of CSA on prenatal care during adulthood. Data from 85 women after CSA were compared to those of 170 matched women without such experiences.

Results: Women exposed to CSA had fewer than five prenatal consultations more often than unexposed women (26%/7%; P<0.0001). Of the 85 women with a positive history for CSA, 9.4% had been asked for such antecedents, 36.5% had intense memories on original abuse situations during pregnancy, 56.6% mentioned specific consequences of CSA on prenatal care and 61.2% were satisfied with obstetrical support. Exposed women (62.4%) felt significantly less prepared for labor than unexposed women (75.9%) (P<0.0001).

Conclusions: CSA experiences are associated with impaired prenatal care. These results underscore the compelling need to improve prenatal care in women exposed to CSA through better education of obstetricians regarding the effects of CSA and in their ability to provide empathetic professional support.
A blueprint for the prevention of preterm birth: vaginal progesterone in women with a short cervix
Authors: Romero Roberto , Yeo Lami , Miranda Jezid , Hassan Sonia S. , Conde-Agudelo Agustin , Chaiworapongsa Tinnakorn 
Published: January 2013

Abstract
Preterm birth is the leading cause of perinatal morbidity and mortality worldwide, and is the most important challenge to modern obstetrics. A major obstacle has been that preterm birth is treated (implicitly or explicitly) as a single condition. Two thirds of preterm births occur after the spontaneous onset of labor, and the remaining one third after “indicated” preterm birth; however, the causes of spontaneous preterm labor and “indicated” preterm birth are different. Spontaneous preterm birth is a syndrome caused by multiple etiologies, one of which is a decline in progesterone action, which induces cervical ripening. A sonographic short cervix (identified in the midtrimester) is a powerful predictor of spontaneous preterm delivery. Randomized clinical trials and individual patient meta-analyses have shown that vaginal progesterone reduces the rate of preterm delivery at <33 weeks of gestation by 44%, along with the rate of admission to the neonatal intensive care unit, respiratory distress syndrome, requirement for mechanical ventilation, and composite neonatal morbidity/mortality score. There is no evidence that 17-α-hydroxyprogesterone caproate can reduce the rate of preterm delivery in women with a short cervix, and therefore, the compound of choice is natural progesterone (not the synthetic progestin). Routine assessment of the risk of preterm birth with cervical ultrasound coupled with vaginal progesterone for women with a short cervix is cost-effective, and the implementation of such a policy is urgently needed. Vaginal progesterone is as effective as cervical cerclage in reducing the rate of preterm delivery in women with a singleton gestation, history of preterm birth, and a short cervix (<25 mm).
Cation exchange characterizations of phosphotungstic acid-doped polyvinyl alcohol/polyethersulfone blend membranes by sodium chloride solution
Authors: Madaeni Sayed S. , Amirinejad Sedigheh , Amirinejad Mehdi , Hosseini Sayed M. , Khodabakhshi Alireza 
Published: January 2013

Abstract
Cation exchange membranes were prepared based on polyvinyl alcohol (PVA) and polyethersulfone (PES) polymer blends using dimethyl sulfoxide as solvent and phosphotungstic acid (PWA) as functional group agent. The membranes were fabricated by solution casting method. The effects of PVA-to-PES polymer blend ratio and PWA content on the electrochemical ion exchange properties of the prepared membranes, including fixed ion concentration (FIC), membrane potential, permselectivity, surface charge density, transport number and electrical resistance, were studied. The areal electrical resistance at room temperature was reduced by increasing the PES and decreasing the PWA contents of membranes. The results show that the addition of PWA to the membranes provides additional counterion-conducting passages and enhances the FIC, membrane potential, permselectivity and transport number.
Superabsorbent hydrogels of poly(sodium acrylate) with crude and exfoliated vermiculites
Authors: Mucientes Antonio E. , Santiago Francisca , Carrero Ana María , Talavera Beatriz 
Published: January 2013

Abstract
Novel superabsorbent hydrogels of poly(sodium acrylate) [poly(SA)] with crude vermiculite (CVMT) and exfoliated vermiculite (EVMT) were synthesized and characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). Both types of hybrids are more stable materials than poly(SA) and their thermal stability increases as the clay content increases. The equilibrium water absorbency for each hybrid type varies with the clay content, showing a maximum at 15 wt% and 20 wt% for EVMT and CVMT, respectively. The equilibrium water absorbency is higher for the hybrids than for poly(SA) at clay contents close to their maxima. The swelling kinetics obey a Voigt-based equation. The water desorption kinetics showed the existence of free water and bound water within the polymeric matrix. All of the superabsorbent materials investigated retained the water absorption capacity after repeating five wet-dry cycles.
Enhancement of flexural performance of wood beams using textile fabrics
Authors: Beylergil Bertan , Aktas Alaattin , Pekbey Yeliz 
Published: January 2013

Abstract
The aim of this study was to investigate the flexural performance of wood beams (beech — Fagus orientalis Lipsky) reinforced with woven and selected weft knitted glass fabrics, namely, Milano and plain knit. Some physical and mechanical properties of the beech wood and the textile fabrics were determined in accordance with relevant ASTM standards. Twenty-four wood beams which have two different cross sections (I-shaped and square hollow) were manufactured and tested under a three-point load. They were divided into two groups: Group A specimens were not reinforced to serve as a reference, whereas Group B specimens were reinforced with textile fabrics combined with adhesion. The flexural behavior of the specimens was studied through their load-deflection characteristics. The modes of failure were identified and categorized. The experimental results showed that the load-bearing capacity of reinforced beams increased significantly compared to the beam without reinforcement. This method can be used to repair and strengthen damaged wood beams.
Effects of cutouts on natural frequency of laminated composite plates
Authors: Erkliğ Ahmet , Bulut Mehmet , Yeter Eyüp 
Published: January 2013

Abstract
In this study, the effects of cutouts (circular, square, triangular and elliptical), cutout position and fiber orientations of laminated composite plates on natural frequencies are investigated. In order to study the effects of cutouts on natural frequencies of the composite plates, experiments have been carried out. Finite element analysis is also performed to predict the effects of different cutouts, cutout position, fiber orientation and length of the plate on natural frequencies for E-glass/polyester. Several outcomes and behavioral characteristics are discussed. These outcomes include the cutout shape, cutout orientation and fiber orientation angle. It has been seen that all of the experimental and finite element results are very close to each other. It has also been concluded that the natural frequency of composite plate is affected by the fiber orientation and cutout location but not considerably affected by cutout shape. The results show that fiber orientation angle and cutout location are the most important parameters on the natural frequency. When the fiber orientation angle increases, both bending and twisting natural frequencies decrease. Maximum natural frequency occurs on [(0/90)4]S laminated plate.
A Hybrid Genetic Linkage Map of Two Ecologically and Morphologically Divergent Midas Cichlid Fishes (Amphilophusspp.) Obtained by Massively Parallel DNA Sequencing (ddRADSeq)
Authors: Recknagel Hans , Elmer Kathryn R , Meyer Axel 
Published: January 2013

AbstractCichlid fishes are an excellent model system for studying speciation and the formation of adaptive radiations because of their tremendous species richness and astonishing phenotypic diversity. Most research has focused on African rift lake fishes, although Neotropical cichlid species display much variability as well. Almost one dozen species of the Midas cichlid species complex (Amphilophus spp.) have been described so far and have formed repeated adaptive radiations in several Nicaraguan crater lakes. Here we apply double-digest restriction-site associated DNA sequencing to obtain a high-density linkage map of an interspecific cross between the benthic Amphilophus astorquii and the limnetic Amphilophus zaliosus, which are sympatric species endemic to Crater Lake Apoyo, Nicaragua. A total of 755 RAD markers were genotyped in 343 F2 hybrids. The map resolved 25 linkage groups and spans a total distance of 1427 cM with an average marker spacing distance of 1.95 cM, almost matching the total number of chromosomes (n = 24) in these species. Regions of segregation distortion were identified in five linkage groups. Based on the pedigree of parents to F2 offspring, we calculated a genome-wide mutation rate of 6.6 × 10−8 mutations per nucleotide per generation. This genetic map will facilitate the mapping of ecomorphologically relevant adaptive traits in the repeated phenotypes that evolved within the Midas cichlid lineage and, as the first linkage map of a Neotropical cichlid, facilitate comparative genomic analyses between African cichlids, Neotropical cichlids and other teleost fishes.
Comparative Genomics of a Plant-Pathogenic Fungus,Pyrenophora tritici-repentis, Reveals Transduplication and the Impact of Repeat Elements on Pathogenicity and Population Divergence
Authors: Manning Viola A , Pandelova Iovanna , Dhillon Braham , Wilhelm Larry J , Goodwin Stephen B , Berlin Aaron M , Figueroa Melania , Freitag Michael , Hane James K , Henrissat Bernard , Holman Wade H , Kodira Chinnappa D , Martin Joel , Oliver Richard P , Robbertse Barbara , Schackwitz Wendy , Schwartz David C , Spatafora Joseph W , Turgeon B Gillian , Yandava Chandri , Young Sarah , Zhou Shiguo , Zeng Qiandong , Grigoriev Igor V , Ma Li-Jun , Ciuffetti Lynda M 
Published: January 2013

AbstractPyrenophora tritici-repentis is a necrotrophic fungus causal to the disease tan spot of wheat, whose contribution to crop loss has increased significantly during the last few decades. Pathogenicity by this fungus is attributed to the production of host-selective toxins (HST), which are recognized by their host in a genotype-specific manner. To better understand the mechanisms that have led to the increase in disease incidence related to this pathogen, we sequenced the genomes of three P. tritici-repentis isolates. A pathogenic isolate that produces two known HSTs was used to assemble a reference nuclear genome of approximately 40 Mb composed of 11 chromosomes that encode 12,141 predicted genes. Comparison of the reference genome with those of a pathogenic isolate that produces a third HST, and a nonpathogenic isolate, showed the nonpathogen genome to be more diverged than those of the two pathogens. Examination of gene-coding regions has provided candidate pathogen-specific proteins and revealed gene families that may play a role in a necrotrophic lifestyle. Analysis of transposable elements suggests that their presence in the genome of pathogenic isolates contributes to the creation of novel genes, effector diversification, possible horizontal gene transfer events, identified copy number variation, and the first example of transduplication by DNA transposable elements in fungi. Overall, comparative analysis of these genomes provides evidence that pathogenicity in this species arose through an influx of transposable elements, which created a genetically flexible landscape that can easily respond to environmental changes.
Transcriptional Networks Controlling the Cell Cycle
Authors: Bonke Martin , Turunen Mikko , Sokolova Maria , Vähärautio Anna , Kivioja Teemu , Taipale Minna , Björklund Mikael , Taipale Jussi 
Published: January 2013

AbstractIn this work, we map the transcriptional targets of 107 previously identified Drosophila genes whose loss caused the strongest cell-cycle phenotypes in a genome-wide RNA interference screen and mine the resulting data computationally. Besides confirming existing knowledge, the analysis revealed several regulatory systems, among which were two highly-specific and interconnected feedback circuits, one between the ribosome and the proteasome that controls overall protein homeostasis, and the other between the ribosome and Myc/Max that regulates the protein synthesis capacity of cells. We also identified a set of genes that alter the timing of mitosis without affecting gene expression, indicating that the cyclic transcriptional program that produces the components required for cell division can be partially uncoupled from the cell division process itself. These genes all have a function in a pathway that regulates the phosphorylation state of Cdk1. We provide evidence showing that this pathway is involved in regulation of cell size, indicating that a Cdk1-regulated cell size checkpoint exists in metazoans.
Genetic Analysis ofmlh3Mutations Reveals Interactions Between Crossover Promoting Factors During Meiosis in Baker’s Yeast
Authors: Brown Megan Sonntag , Lim Elisha , Chen Cheng , Nishant K T , Alani Eric 
Published: January 2013

AbstractCrossing over between homologous chromosomes occurs during the prophase of meiosis I and is critical for chromosome segregation. In baker’s yeast, two heterodimeric complexes, Msh4-Msh5 and Mlh1-Mlh3, act in meiosis to promote interference-dependent crossing over. Mlh1-Mlh3 also plays a role in DNA mismatch repair (MMR) by interacting with Msh2-Msh3 to repair insertion and deletion mutations. Mlh3 contains an ATP-binding domain that is highly conserved among MLH proteins. To explore roles for Mlh3 in meiosis and MMR, we performed a structure−function analysis of eight mlh3 ATPase mutants. In contrast to previous work, our data suggest that ATP hydrolysis by both Mlh1 and Mlh3 is important for both meiotic and MMR functions. In meiotic assays, these mutants showed a roughly linear relationship between spore viability and genetic map distance. To further understand the relationship between crossing over and meiotic viability, we analyzed crossing over on four chromosomes of varying lengths in mlh3Δ mms4Δ strains and observed strong decreases (6- to 17-fold) in crossing over in all intervals. Curiously, mlh3Δ mms4Δ double mutants displayed spore viability levels that were greater than observed in mms4Δ strains that show modest defects in crossing over. The viability in double mutants also appeared greater than would be expected for strains that show such severe defects in crossing over. Together, these observations provide insights for how Mlh1-Mlh3 acts in crossover resolution and MMR and for how chromosome segregation in Meiosis I can occur in the absence of crossing over.
Demonstration of Molecular Sensing Using QCM Device Coated with Stimuli-sensitive Hydrogel
Authors: Seida Yoshimi. , Nakano Yuri , Nakano Yoshio 
Published: January 2013

ABSTRACTMolecular sensing using stimuli-responsive viscoelastic property of amphiphilic polymer hydrogel was demonstrated. Thermo-responsive poly(N-isopropylacrylamide); NIPA, hydrogel immobilizing bovine serum albumin (BSA) in its polymer chain was synthesized on the AT-cut QCM (Quartz crystal microbalance). The device was provided to the sensing of anti-BSA antibody. The resonance behavior of QCM in response to the adsorption of anti-BSA antibody on the hydrogel was observed based on both the resonance frequency and resistance of QCM with impedance analysis. The QCM device coated with the LCST polymer hydrogel revealed a characteristic resonance behavior in response to the adsorption of anti-BSA antibody in the collapse phase of gel at which the gel lost most of its hydrated water. The resonance frequency and resistance in the collapsed gel were highly sensitive and their changes in response to the target adsorption were much larger than in the swelling state of gel. The use of the device at the LCST of NIPA gel is ideal because the largest amplification of the adsorption signal is available along with the largest phase change of NIPA gel.
Mechanical properties of NiAl-Mo composites produced by specially controlled directional solidification
Authors: Zhang G. , Hu L. , Hu W. , Gottstein G. , Bogner S. , Bührig-Polaczek A. 
Published: January 2013

ABSTRACTMo fiber reinforced NiAl in-situ composites with a nominal composition Ni-43.8Al-9.5Mo (at.%) were produced by specially controlled directional solidification (DS) using a laboratory-scale Bridgman furnace equipped with a liquid metal cooling (LMC) device. In these composites, single crystalline Mo fibers were precipitated out through eutectic reaction and aligned parallel to the growth direction of the ingot. Mechanical properties, i.e. the creep resistance at high temperatures (HT, between 900 °C and 1200 °C) and the fracture toughness at room temperature (RT) of in-situ NiAl-Mo composites, were characterized by tensile creep (along the growth direction) and flexure (four-point bending, vertical to the growth direction) tests, respectively. In the current study, a steady creep rate of 10-6s-1 at 1100 °C under an initial applied tensile stress of 150MPa was measured. The flexure tests sustained a fracture toughness of 14.5 MPa·m1/2at room temperature. Compared to binary NiAl and other NiAl alloys, these properties showed a remarkably improvement in creep resistance at HT and fracture toughness at RT that makes this composite a potential candidate material for structural application at the temperatures above 1000 °C. The mechanisms responsible for the improvement of the mechanical properties in NiAl-Mo in-situ composites were discussed based on the investigation results.
Growth of Ultra-thin Titanium Dioxide Films by Complete Anodic Oxidation of Titanium Layers on Conductive Substrates
Authors: Wolff Karsten , Heljo Petri , Lupo Donald 
Published: January 2013

ABSTRACTThe growth of thin and ultra-thin titanium dioxide layers was investigated. Oxide films were grown by galvanostatic and potentiodynamic anodisation of evaporated titanium layers on conductive substrates. It is shown that thin-film oxidation differs significantly from anodic oxidation of solid foils or plates, due to the sudden stop of anodisation process before complete oxidation of the thick films. Depending on the pH value and the potential sweep rate, the effective defect density and the dielectric constant of the anodized layers vary from 3·1019 cm-3 to 1020 cm-3and from 16 to 27, respectively, whereas the electrolyte temperature plays only a minor role.