bluuebunny/crossref_metadata_2025_split huggingface dataset:
Does gestational temperature or prenatal sex ratio influence development of sexual dimorphism in a viviparous skink?
Authors: Hare Kelly M. , Yeong Charlene , Cree Alison 
Published: February 2011

AbstractPrenatal sex ratio (through exposure to hormones from siblings in utero) can influence sexually dimorphic traits of many mammals; but research on viviparous reptiles has contrasting outcomes, which have yet to be resolved. The thermal environment experienced during gestation has a strong effect on the phenotype of reptiles, but whether this thermal effect overrides that of prenatal sex ratio has yet to be explored. We experimentally investigated whether the gestation temperature, or litter sex ratio, influences sexually dimorphic traits (head width and axilla–groin length) in a viviparous skink (Oligosoma maccanni). We found that gestation temperature had a significant influence on sexually dimorphic traits of neonates, and at 3 months of age still influenced head width. We found no evidence that traits in either sex were masculinized or feminized in response to litter sex ratio. The development of external sexual dimorphisms increased gradually (all thermal regimes pooled), with neonates showing no sexual dimorphism, 3‐month‐old juveniles showing some sexual dimorphism in head width, and adults having stronger, but incompletely separated, sexual dimorphism for both traits. We suggest that the overlap in sexually dimorphic traits of adult O. maccanni (and perhaps other reptiles) may be better explained by natural variation in temperatures experienced during embryonic development, rather than hormonal effects arising from litter sex ratio. The interaction of hormones and temperature during gestation and the effect of these factors on sexual dimorphism within reptiles deserve further exploration. J. Exp. Zool. 315A:215–221, 2011. © 2011 Wiley‐Liss, Inc.
Tight products and graph expansion
Authors: Daniely Amit , Linial Nathan 
Published: February 2011

AbstractIn this article, we study a new product of graphs called tight product. A graph H is said to be a tight product of two (undirected multi) graphs G1 and G2, if V(H) = V(G1) × V(G2) and both projection maps V(H)→V(G1) and V(H)→V(G2) are covering maps. It is not a priori clear when two given graphs have a tight product (in fact, it is NP‐hard to decide). We investigate the conditions under which this is possible. This perspective yields a new characterization of class‐1 (2k+ 1)‐regular graphs. We also obtain a new model of random d‐regular graphs whose second eigenvalue is almost surely at most O(d3/4). This construction resembles random graph lifts, but requires fewer random bits. © 2011 Wiley Periodicals, Inc. J Graph Theory
Overlap number of graphs
Authors: Cranston Daniel W. , Korula Nitish , LeSaulnier Timothy D. , Milans Kevin G. , Stocker Christopher J. , Vandenbussche Jennifer , West Douglas B. 
Published: February 2011

AbstractAn overlap representation of a graph G assigns sets to vertices so that vertices are adjacent if and only if their assigned sets intersect with neither containing the other. The overlap number φ(G) (introduced by Rosgen) is the minimum size of the union of the sets in such a representation. We prove the following: (1) An optimal overlap representation of a tree can be produced in linear time, and its size is the number of vertices in the largest subtree in which the neighbor of any leaf has degree 2. (2) If δ(G)⩾2 and G≠K3, then φ(G)⩽|E(G)| − 1, with equality when G is connected and triangle‐free and has no star‐cutset. (3) If G is an n‐vertex plane graph with n⩾5, then φ(G)⩽2n − 5, with equality when every face has length 4 and there is no star‐cutset. (4) If G is an n‐vertex graph with n⩾14, then φ(G)⩽n2/4 − n/2 − 1, with equality for even n when G arises from Kn/2, n/2 by deleting a perfect matching. © 2011 Wiley Periodicals, Inc. J Graph Theory
Effects of medicinal herb salvia miltiorrhiza on osteoblastic cells in vitro
Authors: Chin Alice , Yang Yanqi , Chai Lei , Wong Ricky W. K. , Rabie Abou‐Bakr M. 
Published: February 2011

AbstractSufficient osteoinduction is essential for the success and effectiveness of bone grafting. It was previously found that Salvia Miltiorrhiza (SM), a commonly used Chinese herb increased osteogenesis in vivo. The aim of this study is to investigate the effects of SM on bone cells in vitro, in an attempt to get a better understanding on how SM can promote bone remodeling. MC3T3‐E1, an osteoblastic cell line, was cultured with SM for different time intervals (24, 48, and 72 h), whereas the control group consisted of cells cultured without any intervention. The mRNA expression of alkaline phosphatase (ALP), osteocalcin (OCN), osteoprotegerin (OPG), and the receptor activator of nuclear factor kappa B ligand (RANKL) were examined by real‐time polymerase chain reaction (qPCR). The expression of ALP showed an early increase at 24 h by 50% (p < 0.001) and at 48 h by 13% (p < 0.001). OCN was decreased by 22% at 24 h (p < 0.001) but increased by 50% and 88% at 48 and 72 h, respectively (p < 0.001). RANKL showed an early increase at the first two time points of 24 and 48 h by 45% (p < 0.001) and 36% (p < 0.01), respectively, while OPG was up‐regulated at the latter two time points by 10% at 48 h (p < 0.01) and 68% at 72 h (p < 0.001). Thus, OPG/RANKL was down‐regulated first, and then up‐regulated. SM enhances bone remodeling by regulating the gene expression of ALP, OCN, OPG, and RANKL. It is a potential medicinal herb to be utilized in the application that requires stimulation in bone cell activities. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1059–1063, 2011
Effects of surgical correction for the treatment of adult acquired flatfoot deformity: A computational investigation
Authors: Iaquinto Joseph M. , Wayne Jennifer S. 
Published: February 2011

AbstractComputational models of the foot/ankle complex were developed to predict the biomechanical consequences of surgical procedures that correct for Stage II adult acquired flatfoot deformity. Cadaveric leg and foot bony anatomy was captured by CT imaging in neutral flexion and imported to the modeling software. Ligaments were approximated as tension only springs attached at insertion sites. Muscle contraction of the gastrocnemius/soleus complex was simulated through force vectors and desired external loads applied to the model. Ligament stiffnesses were modified to reflect Stage II flatfoot damage, followed by integration of corrective osteotomies—medializing calcaneal osteotomy (MCO) and Evans and calcaneocuboid distraction arthrodesis (CCDA)—to treat flatfoot. Joint angles, tissue strains, calcaneocuboid contact force, and plantar loads were analyzed. The flatfoot simulation demonstrated clinical signs of disease evidenced by degradation of joint alignment. Repair states corrected these joint misalignments with MCO having greatest impact in the hindfoot, and Evans/CCDA having greatest effect in the mid‐ and forefoot. The lateral procedures unevenly strained plantar structures, while offloading the medial forefoot, and increased loading on the lateral forefoot, which was amplified by combining with MCO. The Evans procedure raised calcaneocuboid joint contact force to twice intact levels. Computational results are in agreement with clinical and experimental findings. The model demonstrated potential precursors to such complications as lateral tightness and arthritic development and may thus be useful as a predictor of surgical outcomes. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1047–1054, 2011
Silver‐decorated carbon nanotube networks as SERS substrates
Authors: Chen Yi‐Chieh , Young Robert J. , Macpherson Julie V. , Wilson Neil R. 
Published: February 2011

AbstractWe report on investigations upon a surface‐enhanced Raman scattering (SERS) substrate produced from a two‐dimensional single‐walled carbon nanotube (SWNT) network decorated with Ag nanoparticles. Using the strong and unique Raman spectrum of SWNTs as a reference, the SWNT/Ag nanostructure can be considered to provide two regions: one with an ultrasensitive SERS response for single‐molecule SERS (SMSERS) study; and another with uniform SERS enhancement over an area of several square millimeters for general SERS measurements. We report the appearance of an anomalous Raman feature at around 2180 cm−1 in the high‐sensitivity region which exhibits the characteristics of SMSERS. The SERS performance of the uniform area was characterized using pyridine vapor adsorbed onto the substrate. The presence of the SWNT/Ag nanostructure enhanced the Raman intensity by over seven orders of magnitude, a factor comparable to or exceeding that obtained on SERS substrates reported by other groups. The results indicate great potential to produce highly sensitive, uniform SERS substrates via further fine‐tuning of the nanostructure. Copyright © 2011 John Wiley & Sons, Ltd.
Probing the phase transition behavior of acetonitrile confined in mesoporous silica by FT Raman spectroscopy
Authors: Li Dongxu , Huang Yining 
Published: February 2011

AbstractPhase transitions of acetonitrile confined in mesoporous silica SBA‐15 and mesocellular silica foam (MCF) having different pore diameters of 39.0, 39.9, 28.4, 8.7, and 4.6 nm with corresponding pore openings of 20.9, 12.1, 10.0, 8.7, and 4.6 nm were investigated by FT Raman spectroscopy. Melting and freezing temperature depressions were found for acetonitrile confined in mesoporous silica with pore opening sizes of 20.9, 12.1, 10.0 and 8.7 nm. A thermal hysteresis between the cooling and heating cycles was also observed. It appears that the smaller the pore opening, the larger the depression of melting or freezing temperature. Although two solid (${\bf \alpha}$ and ${\bf \beta}$) phases exist in bulk acetonitrile, only the liquid →β phase transition was detected for acetonitrile confined in the nanopores of mesoporous silica. The ${\bf \beta} \rightarrow {\bf \alpha}$ solid‐to‐solid phase transition was not observed. For the mesoporous silica with the smallest pore size of 4.6 nm, neither the liquid $\rightarrow {\bf \beta}$ nor the ${\bf \beta} \rightarrow {\bf \alpha}$ transition was observed for the confined acetonitrile. The results demonstrate that FT Raman spectroscopy is a useful technique for studying the phase transition behavior of organic compounds confined in silica‐based hosts. Copyright © 2011 John Wiley & Sons, Ltd.
High‐pressure Raman spectroscopy of nanoparticle polyacetylene in a poly(vinyl‐butyral) matrix
Authors: McIntire Michael , Zhao Liang , Kobryanskii Valerii , Chronister Eric 
Published: February 2011

AbstractThe pressure‐induced Raman shifts of six vibrational bands of 20% and 50% trans‐polyacetylene nanoparticles in poly(vinyl‐butyral) matrix films (NPA/PVB) were studied from 0 to 45 kbar using a diamond anvil cell (DAC). The Raman shifts did not depend on the thickness of the two samples studied. Two of the vibrational bands displayed peak positions that depended on the isomeric compositions, with the 20% trans‐NPA/PVB bands being slightly blue‐shifted relative to the 50% trans‐NPA/PVB bands over the 45 kbar pressure range. The Raman bands of NPA/PVB associated with the trans form initially exhibited a relatively large shift at low pressures (P < 10 kbar) along with a drastic change in their band profile. In order to investigate the relative shielding of the vibrational modes studied, a Grüneisen analysis of the pressure‐induced shifts was conducted by estimating the parameters of the Murnaghan equation of state for solid polyacetylene (PA). Four of the six vibrational modes were found to be sensitive to compression of the interchain void space, while the other two modes were insensitive, indicating that they are relatively shielded from the compression of the sample. Copyright © 2011 John Wiley & Sons, Ltd.
Raman evidence of the interaction between multiwalled carbon nanotubes and nanostructured TiO2
Authors: Inoue Fabiana , Ando Rômulo Augusto , Corio Paola 
Published: February 2011

AbstractNanocomposites of carbon nanotubes and titanium dioxide (TiO2) have attracted much attention due to their photocatalytic properties. Although many examples in the literature have visualized these nanocomposites by electron microscopic images, spectroscopic characterization is still lacking with regard to the interaction between the carbon nanotube and TiO2. In this work, we show evidence of the attachment of nanostructured TiO2 to multiwalled carbon nanotubes (MWNTs) by Raman spectroscopy. The nanostructured TiO2 was characterized by both full‐width at half‐maximum (FWHM) and the Raman shift of the TiO2 band at ca 144 cm−1, whereas the average diameter of the crystallite was estimated as approximately 7 nm. Comparison of the Raman spectra of the MWNTs and MWNTs/TiO2 shows a clear inversion of the relative intensities of the G and D bands, suggesting a substantial chemical modification of the outermost tubes due to the attachment of nanostructured TiO2. To complement the nanocomposite characterization, scanning electronic microscopy and X‐ray diffraction were performed. Copyright © 2011 John Wiley & Sons, Ltd.
Ultrafast nonlinear spectroscopy of a single silver nanoparticle
Authors: Baida H. , Christofilos D. , Maioli P. , Crut A. , Del Fatti N. , Vallée F. 
Published: February 2011

AbstractThe time‐domain nonlinear spectroscopy of a single silver nano‐object is investigated by combining the spatial modulation linear spectroscopy technique with a high‐sensitivity femtosecond pump–probe setup. The investigated single nanoparticle is first optically characterized for size and shape via quantitative measurement of its linear absorption spectrum, and time‐resolved nonlinear pump‐probe measurements are subsequently performed on the same particle. The breathing mode period of a single nanoparticle measured in the time domain is found to be in good agreement with that inferred by the optically deduced particle characteristics, opening the way of full optical investigation of the acoustic response of the characterized single nanoparticles. Copyright © 2011 John Wiley & Sons, Ltd.
The effects of moderately oxidised dietary oil with or without vitamin E supplementation on performance, nutrient digestibility, some blood traits, lipid peroxidation and antioxidant defence of male broilers
Authors: Açıkgöz Zümrüt , Bayraktar Hakan , Altan Özge , Akhisaroglu Serpil Tanriverdi , Kırkpınar Figen , Altun Zekiye 
Published: February 2011

AbstractBACKGROUND: The experiment was conducted to determine the effects of dietary supplementation of oxidised oil with or without vitamin E on performance, nutrient digestibility, some blood traits, lipid peroxidation and antioxidant defence system of male broilers.RESULTS: The supplementation of oxidised oil with or without vitamin E to the grower diets did not significantly affect performance, the pH and viscosity values of excreta and nutrient digestibilities in male broilers. Oxidised oil supplementation slightly increased plasma triglyceride and cholesterol concentrations but did not alter plasma glucose concentration. Although malondialdehyde (MDA) and nitric oxide concentrations tended to be higher in the oxidised oil group, these increases were not significant. Birds fed the diet containing oxidised oil had significantly lower superoxide dismutase (SOD) activity. However, no differences were observed in glutathione peroxidase (GSH‐Px) activity and uric acid concentrations of broilers fed oxidised oil as compared to the control group. Dietary vitamin E supplementation decreased MDA concentration whereas increasing SOD activity, suggesting that vitamin E supplementation reduced susceptibility to lipid peroxidation.CONCLUSION: The results showed that a milder oxidative stress occurred by supplementation of moderately oxidised oil to the diet of broilers and vitamin E supplementation had been helpful in alleviating lipid peroxidation. Copyright © 2011 Society of Chemical Industry
Improved solvent collection system for a dispersive liquid–liquid microextraction of organochlorine pesticides from water using low‐density organic solvent
Authors: Chang Chu‐Chi , Wei Shuo‐Yang , Huang Shang‐Da 
Published: February 2011

AbstractIn this study, the organochlorine pesticides (OCPs) levels in lake and tap water samples were determined by a dispersive liquid–liquid microextraction method using a low‐density organic solvent and an improved solvent collection system (DLLME‐ISCS). This method used a very small volume of a solvent of low toxicity (11 μL of 1‐nonanol and 400 μL of methanol) to extract OCPs from 10 mL water samples prior to the analysis by GC. After centrifugation in the dispersive liquid–liquid microextraction, there was a liquid organic drop floating between the water surface and the glass wall of the centrifuge tube. The liquid organic drop (with some water phase) was transferred into a microtube (3 mm×15 mm) with a syringe. The organic and aqueous phases were separated in the microtube immediately. Then, 1 μL of the organic solvent (which was in the upper portion of liquid in the microtube) was easily collected by a syringe and injected into the GC‐ECD system for the analysis. Under optimum conditions, the linear range of this method was 5–5000 ng/L for most of the analytes. The correlation coefficient was higher than 0.997. Enrichment factors ranged from 1309 to 3629. The relative recoveries ranged from 73 to 119% for lake water samples. The LODs of the method ranged from 0.7 to 9.4 ng/L. The precision of the method ranged from 1.0 to 10.8% for lake water.
Novel criteria for fast searching for optimal method in gradient ion chromatography: An integrated approach
Authors: Ukić Šime , Bolanča Tomislav , Rogošić Marko 
Published: February 2011

AbstractIn this article, an integrated approach for prediction and optimization in ion chromatography (IC) was presented. The approach provides a fast and reliable insight in the elution behavior of an IC system. The predictions are based on a mathematical model that predicts ion retentions (for both isocratic and gradient modes) by using an empirical isocratic model. Other chromatographic values significant for the optimal elution conditions (resolution, peak asymmetry) are calculated quickly and easily from the predicted retention values of characteristic points of a chromatographic peak. Every day, IC users might find this approach a suitable tool for finding optimal IC elution conditions in a given system.
Optical‐fiber microcoil waveguides and resonators and their applications for interferometry and sensing
Authors: Scheuer J. , Sumetsky M. 
Published: February 2011

AbstractIn this work, recent progress in the theoretical and experimental studies of optical‐fiber microcoil waveguides and resonators, as well as their various applications are reviewed. In particular, the focus is set on sensing and interferometry applications. It is shown that due to its inherently low propagation and fiber‐coupling losses, fiber‐microcoil based sensors and interferometers offer substantial enhancement of sensitivity and compactness compared to other types of devices. Recent progress in the realization and experimental characterization of such structures is presented and the theoretical tools to analyze the impact of real‐world nonuniformities on the characteristics of fiber‐microcoil structures are provided.
Upper leg conduction time distinguishes demyelinating neuropathies
Authors: Maccabee Paul J. , Eberle Larry P. , Stein Ian A.G. , Willer Justin A. , Lipitz Mark E. , Kula Roger W. , Marx Tatiana , Muntean Eugeniu V. , Amassian Vahe E. 
Published: February 2011

AbstractBackground: The objective of this study was to determine whether differentiation between demyelinating and axonal neuropathies could be enhanced by comparing conduction time changes in defined segments of the total peripheral nerve pathway. Methods: Compound muscle action potentials (CMAPs) were elicited by cathodal stimulation of the tibial nerve at the ankle and popliteal fossa, and by paravertebral neuromagnetic stimulation at proximal and distal cauda equina while recording from muscles of the foot, shin, and thigh. Segmental conduction times were calculated in normal subjects; in patients with lumbosacral radiculopathy, distal symmetric diabetic neuropathy, amyotrophic lateral sclerosis, acute and chronic inflammatory demyelinating polyneuropathy; and in patients with anti–myelin‐associated glycoprotein, myelomatous, and Charcot–Marie–Tooth type 1a polyneuropathies. Results: Distal cauda equina latency and CMAP duration and segmental conduction times in upper leg and cauda equina facilitated differentiation of demyelinating from axonal neuropathies, even in the presence of a range of reduced amplitude CMAPs. Conclusions: Within the demyelinating neuropathy spectrum, it was further possible to distinguish subtypes. Muscle Nerve, 2011
Single‐and multi‐objective genetic algorithm optimization for identifying soil parameters
Authors: Papon A. , Riou Y. , Dano C. , Hicher P.‐Y. 
Published: February 2011

SUMMARYThis paper discusses the quality of the procedure employed in identifying soil parameters by inverse analysis. This procedure includes a FEM‐simulation for which two constitutive models—a linear elastic perfectly plastic Mohr–Coulomb model and a strain‐hardening elasto‐plastic model—are successively considered. Two kinds of optimization algorithms have been used: a deterministic simplex method and a stochastic genetic method. The soil data come from the results of two pressuremeter tests, complemented by triaxial and resonant column testing. First, the inverse analysis has been performed separately on each pressuremeter test. The genetic method presents the advantage of providing a collection of satisfactory solutions, among which a geotechnical engineer has to choose the optimal one based on his scientific background and/or additional analyses based on further experimental test results. This advantage is enhanced when all the constitutive parameters sensitive to the considered problem have to be identified without restrictions in the search space. Second, the experimental values of the two pressuremeter tests have been processed simultaneously, so that the inverse analysis becomes a multi‐objective optimization problem. The genetic method allows the user to choose the most suitable parameter set according to the Pareto frontier and to guarantee the coherence between the tests. The sets of optimized parameters obtained from inverse analyses are then used to calculate the response of a spread footing, which is part of a predictive benchmark. The numerical results with respect to both the constitutive models and the inverse analysis procedure are discussed. Copyright © 2011 John Wiley & Sons, Ltd.