bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tuning mesomorphic properties and handedness of chiral calamitic liquid crystals by minimal modification of the effective core
Authors: Liu Anhua , Sun Qiming , Cui Jiaxi , Zheng Jia , Liu Wenjian , Wan Xinhua 
Published: September 2011

AbstractTwo pairs of calamitic liquid crystalline molecules, (+)‐2‐[4′‐(S)‐sec‐butoxyphenyl]‐5‐(4′‐hexoxyphenyl)toluene ((+)-S-1) and (+)‐2‐(4′‐hexoxyphenyl)‐5‐[4′‐(S)‐sec‐butoxyphenyl]toluene ((+)-S-2), (−)‐2‐[4′‐(R)‐sec‐butoxyphenyl]‐5‐(4′‐hexoxyphenyl)toluene ((-)-R-1) and (−)‐2‐(4′‐hexoxyphenyl)‐5‐[4′‐(R)‐sec‐butoxyphenyl]toluene ((-)-R-2), have been designed and synthesized. Each of the molecules consists of a p‐terphenyl core substituted with a methyl group on the middle ring, a chiral sec‐butoxy tail, and an achiral n‐hexoxy tail. The geometrical difference between (+)-S-1 ((-)-R-1) and (+)-S-2 ((-)-R-2) lies only in the location of the methyl group on the effective mesogenic core. Yet, such a small change in the structure gives rise to remarkable differences in mesogenic properties and handedness. Both (+)-S-1 and (-)-R-1 have an enantiotropic cholesteric phase (N*) and a monotropic twist grain boundary C* phase (TGBC*), whereas (+)-S-2 and (-)-R-2 exhibit only a monotropic N* phase. Moreover, (+)-S-1 ((-)-R-1) and (+)-S-2 ((-)-R-2) have opposite handedness in the N* phase, and (+)-S-1 and (-)-R-1 even have a helical inversion from N* to TGBC* phase through a non‐helical chiral mesophase. Chirality, 2011. © 2011 Wiley Periodicals, Inc.
Therapeutic opportunities in dengue infection
Authors: Fagundes Caio T. , Costa Vivian V. , Cisalpino Daniel , Souza Danielle G. , Teixeira Mauro M. 
Published: September 2011

AbstractInfection by one of the four serotypes of the arthropod‐borne dengue virus produces a spectrum of disease manifestations, ranging from asymptomatic to life‐threatening Dengue hemorrhagic fever/Dengue shock syndrome (DHF/DSS). During the last several decades, dengue has spread its geographic distribution to become the most common arboviral infection of humans in the subtropical and tropical regions of the world. There is no specific treatment or vaccine approved for human use. This fact, associated with the large number of infected individuals and the lack of markers that indicate which patients will develop severe disease, place an enormous burden on health systems of affected countries. Many efforts have been made to elucidate several aspects of dengue disease, but the pathogenesis of disease is complex and remains unclear. The hallmark of severe dengue disease is a short‐lived plasma leakage that is believed to be immune mediated. Understanding the mechanism(s) that underlie the pathogenesis of dengue is critical for the development of safe therapeutics to prevent DHF/DSS. In this review, we highlight potential therapeutic alternatives to treat dengue infection and outline strategies used to develop and research anti‐dengue therapies, focusing on in vivo results obtained using the experimental animal models currently available. Within this context, we discuss the therapeutic potential of novel antiviral molecules, either targeting virus‐encoded functions or the cellular functions needed for viral replication. In addition, we discuss studies using anti‐inflammatory strategies aimed at reducing the exacerbated host response against infection and their potential as promising therapeutic alternatives in severe dengue disease. Drug Dev Res 72:480–500, 2011. © 2011 Wiley‐Liss, Inc.
Potentiometric Sensing of Lamotrigine Based on Molecularly Imprinted Polymers
Authors: Sadeghi Hayedeh Bagheri , Ebrahimi Soltan Ahmad , Tamaddon Atefeh , Bozorgvar Fatemeh , Afifinia Hadi , Almasian Nasim , Mollaei Somayeh 
Published: September 2011

AbstractIn the present work a novel potentiometric sensor, based on a noncovalent imprinted polymer, was developed for determination of Lamotrigine (LTG). At optimized conditions the electrode exhibited a Nernstian response (30.8±1.0 mV decade−1) in a concentration range of 1×10−6 to 1×10−3 M with a detection limit of 8×10−7 mol L−1. The potential response of the electrode was constant in the pH range of 1.0–5.0. The electrode demonstrated a response time of ∼30 s. The selectivity coefficient of the sensor toward a number of different drugs with molecular similarities and some metal ions was evaluated. The electrode was examined for determination of LTG in real samples.
Chromium(III) Potentiometric Sensor Based on Para‐Tertiary‐Butyl Calix[4]arene
Authors: Bagheri Sadeghi Hayedeh , Tamaddon Atefeh , Afifinia Hadi , Almasian Nasim , Bozorgvar Fatemeh , Mollaei Somayeh 
Published: September 2011

AbstractA new chromium(III) PVC membrane sensor incorporating p‐tertiary‐butyl calix[4]arene as ionophore, potassium tetrakis as additive and dibutyl phthalate (DBP) as plasticizer was constructed. The electrode exhibited an excellent potentiometric response over a wide concentration range of 1.0×10−7–1.0×10−1 M with a Nernstian slope of 20±0.5 mV per decade. The detection limit was 5.0×10−8 M. The electrode showed a better performance over a pH range of 3.0–8.0, and had a short response time of about <15 s.The electrode was successfully applied to potentiometric titration of Cr (III) with EDTA and for direct determination of chromium(III) in waste water.
Controlling Field‐Effect Transistor Biosensor Electrical Characteristics Using Immunosorbent Assay
Authors: Vaknin Oshri , Khamaisi Bassam , Mizrahi Mordechay , Ashkenasy Nurit 
Published: September 2011

AbstractA method to modulate the signal of field‐effect transistor biosensors using an immunosorbent assay is described. A model system is used to show that binding of a secondary antibody, to which highly charged gold colloids are attached, to an analyte on the device floating gate can be used to induce strong electrostatic effects, which affect the device threshold voltage and source‐drain current. This process may be used for signal amplification, with the secondary binding specificity allowing for improved signal to noise ratio, which is of great importance for early disease detection.
Can cytogenetics explain the possible association between exposure to extreme low‐frequency magnetic fields and Alzheimer's disease?
Authors: Maes Annemarie , Verschaeve Luc 
Published: September 2011

ABSTRACTRecently, a number of epidemiological studies have suggested that occupational as well as residential exposure to extreme low‐frequency electromagnetic fields (ELF‐EMFs) may be a risk factor for Alzheimer's disease. This is not proven yet and there are no known biological mechanisms to explain this alleged association. Alzheimer's disease is characterized by a number of events that have, at least partially, a genetic origin. In particular, trisomy of chromosomes 17 and 21 seems to be involved. Overall ELF‐EMFs have not been identified as genotoxic agents, but there are some papers in the scientific literature that indicate that they may enhance the effects of agents that are known to induce mutations or tumors. There are also some indications that ELF‐EMFs may induce aneuploïdy. This opens some perspectives for investigating the alleged association between ELF‐EMFs and Alzheimer's. This paper reviews the possibility of a cytogenetic association between the electromagnetic fields and Alzheimer's disease. Copyright © 2011 John Wiley & Sons, Ltd.
Facile micropatterning of dual hydrogel systems for 3D models of neurite outgrowth
Authors: Curley J. Lowry , Moore Michael J. 
Published: September 2011

AbstractUnderstanding how microenvironmental factors influence neurite growth is important to inform studies in nerve regeneration, plasticity, development, and neurophysiology. In vitro models attempting to more accurately mimic the physiological environment by provision of a 3D growth matrix may provide useful foundations. Some limitations of thick 3D culture models include hampered solute transport, less‐robust neurite growth than on 2D substrates, and difficulty in achieving spatial control of growth. To this end, we describe a 3D dual hydrogel model for embryonic rat day 15 dorsal root ganglion tissue explant growth using a digital micromirror device for dynamic mask projection photolithography. The photolithography method developed allowed simple, reproducible, one‐step fabrication of thick hydrogel constructs on a variety of substrates, including permeable cell culture inserts. The relationships between projected mask size, crosslinked hydrogel resolution, and gel thickness were characterized, and resolution was found generally to decrease with increasing gel thickness. Cell viability in thick (481 μm) hydrogel constructs was significantly greater on permeable supports than glass, suggesting transport limitations were somewhat alleviated. The observed neurite growth was abundant and occurred in a spatially controlled manner throughout the 3D environment, a crucial step in the quest for a more effective biomimetic model of neurite outgrowth. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2011.
Switchable Supramolecular Crosslinking of Cyclodextrin‐Modified Hyperbranched Polyethylenimine via Anthraquinone Dyes
Authors: Böhm Indra , Kreth S. Katharina , Ritter Helmut , Branscheid Robert , Kolb Ute 
Published: September 2011

AbstractTwo anthraquinone dyes, 5,8‐di‐N‐adamantylamino‐1,4‐dihydroxyanthraquinone (AQ‐OH) and 1,4‐di‐N‐adamantylaminoanthraquinone (AQ‐H), are synthesized. The combination of AQ‐OH and AQ‐H with hyperbranched polyethylenimine (PEI) bearing covalently attached β‐cyclodextrin spontaneously formed host–guest complexes with hydrodynamic diameters of about 260 nm. Even enlarged structures of the trifunctional AQ‐H were observed via DLS. Repeated measurements show that their assembly and disassembly is reversible with a critical point at 26 °C and therefore switchable via temperature. Also superstructures up to 100 μm were detected via TEM, cryo‐TEM‐, and SEM. Hence, a smart colored network of switchable size consisting of a supramolecular approach involving an organic dye is described.
Fractal dimension of an intrinsically disordered protein: Small‐angle X‐ray scattering and computational study of the bacteriophage λ N protein
Authors: Johansen Daniel , Trewhella Jill , Goldenberg David P. 
Published: September 2011

AbstractSmall‐angle X‐ray scattering (SAXS) was used to characterize the bacteriophage λ N protein, a 107 residue intrinsically disordered protein (IDP) that functions as a transcriptional antitermination factor. The SAXS data were used to estimate both the average radius of gyration and the fractal dimension, a measure of the protein's internal scaling properties, under a variety of solution conditions. In the absence of denaturants, the radius of gyration was 38 ± 3.5 Å and the fractal dimension was 1.76 ± 0.05, slightly larger than the value predicted for a well‐solvated polymer with excluded volume (1.7). Neither the radius of gyration nor the fractal dimension changed significantly on the addition of urea, further indicating that the protein is extensively unfolded and well solvated in the absence of denaturant. The addition of NaCl or D2O was found to promote aggregation, but did not appear to affect the properties of the monomeric form. The experimental SAXS profiles were also compared with those predicted by a computational model for a random‐coil polypeptide, with an adjustable solvation energy term. The experimental data were well fit to the model with the solvation energy close to zero. These results indicate that the λ N protein is among the more expanded members of the broad class of IDPs, most likely because of its high content of charged residues and a large net charge (+15 at neutral pH). The expanded nature of the conformational ensemble may play a role in facilitating the interactions of the protein with other components of the dynamic transcriptional complex.
Insights into the structural stability of Bax from molecular dynamics simulations at high temperatures
Authors: Rosas‐Trigueros Jorge Luis , Correa‐Basurto José , Guadalupe Benítez‐Cardoza Claudia , Zamorano‐Carrillo Absalom 
Published: September 2011

AbstractBax is a member of the Bcl‐2 protein family that participates in mitochondrion‐mediated apoptosis. In the early stages of the apoptotic pathway, this protein migrates from the cytosol to the outer mitochondrial membrane, where it is inserted and usually oligomerizes, making cytochrome c‐compatible pores. Although several cellular and structural studies have been reported, a description of the stability of Bax at the molecular level remains elusive. This article reports molecular dynamics simulations of monomeric Bax at 300, 400, and 500 K, focusing on the most relevant structural changes and relating them to biological experimental results. Bax gradually loses its α‐helices when it is submitted to high temperatures, yet it maintains its globular conformation. The resistance of Bax to adopt an extended conformation could be due to several interactions that were found to be responsible for maintaining the structural stability of this protein. Among these interactions, we found salt bridges, hydrophobic interactions, and hydrogen bonds. Remarkably, salt bridges were the most relevant to prevent the elongation of the structure. In addition, the analysis of our results suggests which conformational movements are implicated in the activation/oligomerization of Bax. This atomistic description might have important implications for understanding the functionality and stability of Bax in vitro as well as within the cellular environment.
In Situ Imaging of Multiphase Bio‐interfaces at the Micro‐/Nanoscale
Authors: Chen Peipei , Jiang Lei , Han Dong 
Published: September 2011

AbstractThe multiphase bio‐interfacial system constituted by biological surfaces and their surrounding environment is usually considered to be an essential clue for exploring the mysterious relationship between surface architecture and function. As a visualizing method to understand these systems, in situ imaging of multiphase interfaces (e.g., air/liquid/solid and oil/water/solid systems) at the micro‐/nanoscale, still remains a huge challenge, as a result of their heterogeneity and complexity. Here, recent progress on real‐space micro‐/nanoscale imaging of multiphase bio‐interfacial systems is reviewed; this includes several techniques and imaging results on bio‐interfaces, such as the lotus leaf, fish scale, living cell's surface, and fresh tissue surface. The results evidently show that interfacial structures have a significant impact on the state of the microscopic multiphase interface, further influencing specific functions. Based on this research, technical innovations, some more complicated multiphase interface systems, and structure–function coupling mechanism are proposed.
Remarks on Neuber's complex variable procedure for plane elastic solutions
Authors: Knops R.J. , Villaggio P. 
Published: September 2011

AbstractThe last edition of the book by Neuber on notch stresses derives solutions to several isotropic plane elastic problems using an elegant modification of the standard complex variable method. The procedure, however, can lead to an apparently overlooked but major error in the calculation of the stress function that severely limits the validity of the final results. Here, the necessary amendments are introduced and illustrated by simple examples that nevertheless reveal the essential features of our criticism.
Residual based sampling in POD model order reduction of drift‐diffusion equations in parametrized electrical networks
Authors: Hinze M. , Kunkel M. 
Published: September 2011

AbstractWe consider integrated circuits with semiconductors modeled by modified nodal analysis and drift‐diffusion equations. The drift‐diffusion equations are discretized in space using mixed finite element method. This discretization yields a high dimensional differential‐algebraic equation. We show how proper orthogonal decomposition (POD) can be used to reduce the dimension of the model. We compare reduced and fine models and give numerical results for a basic network with one diode. Furthermore we discuss an adaptive approach to construct POD models which are valid over certain parameter ranges.
Natural genetic variation in fluctuating asymmetry of wing shape inDrosophila melanogaster
Authors: Tsujino Masahiro , Takahashi Kazuo H. 
Published: September 2011

AbstractFluctuating asymmetry (FA), defined as random deviation from perfect symmetry, has been used to assay the inability of individuals to buffer their developmental processes from environmental perturbations (i.e., developmental instability). In this study, we aimed to characterize the natural genetic variation in FA of wing shape inDrosophila melanogaster, collected from across the Japanese archipelago. We quantified wing shapes at whole wing and partial wing component levels and evaluated their mean and FA. We also estimated the heritability of the mean and FA of these traits. We found significant natural genetic variation in all the mean wing traits and in FA of one of the partial wing components. Heritability estimates for mean wing shapes were significant in two and four out of five wing traits in males and females, respectively. On the contrary, heritability estimates for FA were low and not significant. This is a novel study of natural genetic variation in FA of wing shape. Our findings suggest that partial wing components behave as distinct units of selection for FA, and local adaptation of the mechanisms to stabilize developmental processes occur in nature.
Lipoprint Adequately Estimates LDL Size Distribution, but not Absolute Size, Versus Polyacrylamide Gradient Gel Electrophoresis
Authors: Varady Krista A. , Lamarche Benoît 
Published: September 2011

AbstractRecently, a new cost‐effective and less labor‐intensive technique termed the “lipoprint LDL system” was developed to measure LDL particle size. However, the agreement between lipoprint and previously validated techniques, such as polyacrylamide gradient gel electrophoresis (PGGE), has never been tested. Therefore, we measured LDL size by lipoprint and PGGE in 16 obese subjects at 4 different time points. Lipoprint significantly overestimated (P = 0.003) integrated LDL particle size by 1.1 ± 3.0 Å when compared to PGGE. As for distribution, there was good agreement between methods for the estimation of large, medium, and small particles (mean difference between the methods was <3% for each parameter). Correlational analysis also revealed good relationships between methods for the proportion of large (r = 0.81, P < 0.0001), medium (r = 0.67, P < 0.0001), and small (r = 0.73, P < 0.0001) particles. In sum, although there is good agreement between lipoprint and PGGE for the determination of LDL size distribution, absolute LDL size values may differ between the two methods.
Comparison between the gonadotropin‐releasing hormone antagonist protocol and the gonadotropin‐releasing hormone agonist long protocol for controlled ovarian hyperstimulation in the first in vitro fertilization–embryo transfer cycle in an unspecified population of infertile couples
Authors: Mekaru Keiko , Yagi Chiaki , Asato Kozue , Masamoto Hitoshi , Sakumoto Kaoru , Aoki Yoichi 
Published: September 2011

AbstractPurposeWe aimed to compare the efficacy of a gonadotropin‐releasing hormone (GnRH) antagonist protocol and a GnRH agonist long protocol used in the first in vitro fertilization–embryo transfer (IVF–ET) cycle in an unspecified population of infertile couples.MethodsFifty and 34 patients were treated with a GnRH agonist long protocol (agonist group) and GnRH antagonist protocol (antagonist group), respectively, in the first treatment cycle. The primary and secondary outcome measures were cumulative live birth rates after fresh and cryopreserved–thawed ETs and incidence of grades II and III ovarian hyperstimulation syndrome (OHSS), respectively.ResultsNo significant differences were observed in clinical pregnancy rates (38.0 vs. 32.4%) and live birth rates (22.0 vs. 23.5%), which included both fresh and cryopreserved–thawed ETs, between the 2 groups. However, the incidence of grade III OHSS was significantly lower with the GnRH antagonist protocol than the GnRH agonist long protocol.ConclusionsUsed in the first IVF–ET cycle in an unspecified population of infertile patients, the GnRH antagonist protocol showed the same clinical outcome as the GnRH agonist long protocol.
Japan in the Seventeenth Century: Labour Relations and Work Ethics
Authors: Mathias Regine 
Published: September 2011

SummaryIn Japan, the transformation of labour relations from medieval forms of serfdom, lifelong service, and corvée labour to short-term contracts and wage labour was already under way by the seventeenth century. In the second half of the seventeenth century short-term employment based on contracts became common. Indentured labour gradually changed into wage labour. Government policies included enabling greater mobility for the workers, while also trying to set limits to migration flow to the cities. Some Confucian scholars welcomed this new form of labour relations; others condemned them. The few sources about the work ethics of waged workers imply mockery about their loose morals and work attitudes, but also complaints about workloads and exploitation.
Distribution of serogroups and sequence types in disease-associated and carrier strains ofNeisseria meningitidisisolated in China between 2003 and 2008
Authors: ZHOU H. , GAO Y. , XU L. , LI M. , LI Q. , LI Y. , LIANG X. , LUO H. , KAN B. , XU J. , SHAO Z. 
Published: September 2011

SUMMARYGiven the unpredictability ofNeisseria meningitidisoutbreaks and the increased prevalence of serogroup C strains following the introduction of serogroup A-based vaccines, we conducted an analysis of serogroups and sequence types (STs) in disease-associated and carrierN. meningitidisisolates that have emerged in China since 2003. We used multilocus sequence-typing techniques to investigate 371N. meningitidisstrains isolated from patients with meningitis and healthy carriers. Two lineages were identified in serogroup A and C isolates, genotyped as the ST5 complex and ST4821 complex, respectively. Both clonal complexes were found throughout China, although ST4821 was more concentrated in the eastern region of the country. The ST5 complex has been persistent in China since the late 1980s and has since spread across the entire country. Isolates belonging to the ST4821 complex have been a dominant lineage since 2003.