bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intraspecific variability modulates interspecific variability in animal organismal stoichiometry
Authors: El‐Sabaawi Rana W. , Travis Joseph , Zandonà Eugenia , McIntyre Peter B. , Reznick David N. , Flecker Alexander 
Published: March 2014

AbstractInterspecific differences in organismal stoichiometry (OS) have been documented in a wide range of animal taxa and are of significant interest for understanding evolutionary patterns inOS. In contrast, intraspecific variation in animalOShas generally been treated as analytical noise or random variation, even though available data suggest intraspecific variability inOSis widespread. Here, we assess how intraspecific variation inOSaffects inferences about interspecificOSdifferences using two co‐occurring Neotropical fishes:Poecilia reticulataandRivulus hartii. A wide range ofOShas been observed within both species and has been attributed to environmental differences among stream systems. We assess the contributions of species identity, stream system, and the interactions between stream and species to variability in N:P, C:P, and C:N. Because predation pressure can impact the foraging ecology and life‐history traits of fishes, we compare predictors ofOSbetween communities that include predators, and communities where predators are absent. We find that species identity is the strongest predictor of N:P, while stream or the interaction of stream and species contribute more to the overall variation in C:P and C:N. Interspecific differences in N:P, C:P, and C:N are therefore not consistent among streams. The relative contribution of stream or species toOSqualitatively changes between the two predation communities, but these differences do not have appreciable effects in interspecific patterns. We conclude that although species identity is a significant predictor ofOS, intraspecificOSis sometimes sufficient to overwhelm or obfuscate interspecific differences inOS.
Calixarene‐Mediated Liquid‐Membrane Transport of Choline Conjugates
Authors: Adhikari Birendra Babu , Fujii Ayu , Schramm Michael P. 
Published: March 2014

AbstractA series of supramolecular calixarenes efficiently transport distinct molecular species through a liquid membrane when attached to a receptor‐complementary choline handle. Calix[6]arene hexacarboxylic acid was highly effective at transporting different target molecules against a pH gradient. Both carboxylic‐ and phosphonic‐acid‐functionalized calix[4]arenes effect transport without requiring a pH or ion gradient. NMR binding studies, two‐phase solvent extraction, and three‐phase transport experiments reveal the necessary and subtle parameters to effect the transport of molecules attached to a choline “handle”. On the other hand, rescorin[4]arene cavitands, which have similar guest recognition profiles, did not transport guest molecules. These developments reveal new approaches towards attempting synthetic‐receptor‐mediated selective small‐molecule transport in vesicular and cellular systems.
The impact of beaver dams on the morphology of a river in the eastern United States with implications for river restoration
Authors: Curran Joanna Crowe , Cannatelli Kristen M. 
Published: March 2014

ABSTRACTRestoration projects in the United States typically have among the stated goals those of increasing channel stability and sediment storage within the reach. Increased interest in ecologically based restoration techniques has led to the consideration of introducing beavers to degraded channels with the hope that the construction of beaver dams will aggrade the channel. Most research on beaver dam modification to channels has focused on the long‐term effects of beavers on the landscape with data primarily from rivers in the western United States. This study illustrated that a role exists for beavers in the restoration of fine‐grained, low gradient channels.A channel on the Atlantic Coastal Plain was analyzed before, during, and after beaver dams were constructed to evaluate the lasting impact of the beaver on channel morphology. The channel was actively evolving in a former reservoir area upstream of a dam break. Colonization by the beaver focused the flow into the channel, allowed for deposition along the channel banks, and reduced the channel width such that when the beaver dams were destroyed in a flood, there was no channel migration and net sediment storage in the reach had increased. However, the majority of the deposition occurred at the channel banks, narrowing the channel width, while the channel incised between sequential beaver dams. The study indicated that where channels are unstable laterally and bank erosion is a concern, the introduction of beavers can be a useful restoration tool. However, because of the likelihood of increased channel bed erosion in a reach with multiple beaver dams, they may not be the best solution where aggradation of an incised channel bed is the desired result. Copyright © 2014 John Wiley & Sons, Ltd.
Modeling the functional influence of vegetation type on streambank cohesion
Authors: Polvi Lina E. , Wohl Ellen , Merritt David M. 
Published: March 2014

ABSTRACTThe important role of vegetation in adding cohesion and stabilizing streambanks has been widely recognized in several aspects of fluvial geomorphology, including stream restoration and studies of long‐term channel change. Changes in planform between braided, meandering, and anabranching forms have been attributed to the impacts of vegetation on hydraulic roughness and bank stability. However, these studies focus either on flume studies where analog vegetation is used, or case studies featuring one species, which is commonly invasive. We present functional differences of bank‐stabilizing root characteristics and added cohesion, with vegetation categorized as woody and non‐woody and by the vegetation groups of trees, shrubs, graminoids, and forbs. We analyzed root morphology and tensile strength of 14 species common to riparian areas in the southern Rocky Mountains, in field sites along streambanks in the montane and subalpine zones of the Colorado Front Range. Using the vegetation root component (RipRoot) of a physically‐based bank stability model (BSTEM), we estimated the added cohesion for various sediment textures with the addition of each of the 14 species. Significant differences exist between woody and non‐woody vegetation and between the four vegetation categories with respect to the coefficient of the root tensile strength curve, lateral root extent, and maximum root diameter. Woody vegetation (trees and shrubs) have higher values of all three parameters than non‐woody species. Tree roots add significantly more cohesion to streambanks than forb roots. Additionally, rhizomes may play an important role in determining the reach‐scale effects of roots on bank stabilization. Differences in root characteristics and added cohesion among vegetation categories have several important implications, including determining the likelihood of planform change, developing guidelines for the use of bank‐stabilizing vegetation, and linking the effect of vegetation to geomorphic structure that can benefit ecosystem functioning. Copyright © 2014 John Wiley & Sons, Ltd.
Optimised optical wireless car‐to‐traffic‐light communication
Authors: Arnon Shlomi 
Published: March 2014

ABSTRACTIntelligent transport systems have become the major technology for increasing road safety and traffic efficiency, as well as for reducing the number of road casualties. Radio frequency and optical wireless communication technologies have been proposed as a means for establishing communication between vehicular and road infrastructure, such as traffic lights, billboards and road infrastructures and for providing inter‐vehicular communication. These technologies provide one‐way or two‐way short‐range to medium‐range wireless communication links that are specifically designed for the automotive sphere. The technology that is analysed in this paper is optical wireless communication. This technology modulates optical data on top of the illumination in the traffic lights and in the automotive lighting and detects the information using fast imaging sensors. Using knowledge of the amplitudes of the signal and the noise in each pixel, we tune adaptively and separately the gain of each individual pixel in the imaging sensor for communication signals. Tuning the gain is based on the mathematical model derived in this research. Comparison is made between the adaptive model and the standard model. From the mathematical analysis and the results of the comparison, it is clear that this model significantly improves communication system performance. In our numerical calculation for a given set of parameters, the signal‐to‐noise ratio of the standard system and the adaptive system changes from more than 7 × 10 − 4 to more than 7 and less than 2 × 10 − 3 to more than 30 for a change in transmitter power from 10 to 100 watts respectively. Copyright © 2014 John Wiley & Sons, Ltd.
Redox control of enzymatic functions: The electronics of life's circuitry
Authors: Bonini Marcelo G. , Consolaro Marcia E. L. , Hart Peter C. , Mao Mao , de Abreu Andre Luelsdorf Pimenta , Master Alyssa M. 
Published: March 2014

AbstractThe field of redox biology has changed tremendously over the past 20 years. Formerly regarded as bi‐products of the aerobic metabolism exclusively involved in tissue damage, reactive oxygen species (ROS) are now recognized as active participants of cell signaling events in health and in disease. In this sense, ROS and the more recently defined reactive nitrogen species (RNS) are, just like hormones and second messengers, acting as fundamental orchestrators of cell signaling pathways. The chemical modification of enzymes by ROS and RNS (that result in functional enzymatic alterations) accounts for a considerable fraction of the transient and persistent perturbations imposed by variations in oxidant levels. Upregulation of ROS and RNS in response to stress is a common cellular response that foments adaptation to a variety of physiologic alterations (hypoxia, hyperoxia, starvation, and cytokine production). Frequently, these are beneficial and increase the organisms' resistance against subsequent acute stress (preconditioning). Differently, the sustained ROS/RNS‐dependent rerouting of signaling produces irreversible alterations in cellular functioning, often leading to pathogenic events. Thus, the duration and reversibility of protein oxidations define whether complex organisms remain “electronically” healthy. Among the 20 essential amino acids, four are particularly susceptible to oxidation: cysteine, methionine, tyrosine, and tryptophan. Here, we will critically review the mechanisms, implications, and repair systems involved in the redox modifications of these residues in proteins while analyzing well‐characterized prototypic examples. Occasionally, we will discuss potential consequences of amino acid oxidation and speculate on the biologic necessity for such events in the context of adaptative redox signaling. © 2014 IUBMB Life, 66(3):167–181, 2014
Properties and in vitro evaluation of high modulus biodegradable polyurethanes for applications in cardiovascular stents
Authors: Sgarioto Melissa , Adhikari Raju , Gunatillake Pathiraja A. , Moore Tim , Malherbe François , Nagel Marie‐Danielle , Patterson John 
Published: March 2014

AbstractThis study examined the suitability of a family of biodegradable polyurethanes (PUs) NovoSorbTM developed for the vascular stent application. These segmented PUs are formulated to be biodegradable using degradable polyester and PU blocks. A series of PUs comprising different hard segment weight percentage ranging from 60 to 100 were investigated. The mechanical properties of the PUs were evaluated before and after gamma sterilization to assess their suitability for vascular implants. The real‐time (PBS/37°C/pH 7.4) hydrolytic degradation studies were carried out under sterile conditions and PU glass transition temperature, molecular weight, and mass loss at 3, 6, and 9 months were determined. The viability and growth of Human Umbilical Vein Endothelial Cells (HUVEC) on PU surfaces were determined to assess the effect of PU degradation. The effect of coating of extracellular matrix (ECM) components on cell viability was also investigated. The study showed that the PUs possess excellent mechanical properties exhibiting high tensile strength (41–56 MPa) and tensile modulus (897–1496 MPa). The PU films maintained mechanical strength during the early phase of the degradation but lost strength at latter stages. The unmodified polymer surface of each PU promotes endothelial cell growth and proliferation, with a HUVEC retention rate of >70%. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1711–1719, 2014.
A Simple, Selective and Sensitive Immunoassay for Determination of Human Chorionic Gonadotrophin Based on Chemiluminescence Resonance Energy Transfer
Authors: Lei Jiuqian , Mei Surong , Zhou Yikai , Jing Tao 
Published: March 2014

AbstractA simple, selective and sensitive immunoassay was developed for the determination of human chorionic gonadotrophin (HCG) based on the chemiluminescence resonance energy transfer (CRET). Two kinds of antibodies were used to form a sandwich‐type immunocomplex to ensure the selectivity of immunoassay. Based on the simple magnetic separation, amplification feature of gold nanoparticles and CRET phenomenon, this method could be used for highly sensitive determination of HCG without tedious washing steps. Under the optimized conditions, a linear range was obtained when the concentrations of HCG were changed from 0.15 to 5 mIU mL−1 (R = 0.992). This immunoassay could be used for the determination of HCG in serum samples, which provided a promising potential in clinical diagnosis.
Development of a New Cr(VI)‐biosorbent from Agricultural Waste: Adsorption Characteristics and the Kinetics
Authors: Shanmugaprakash M. , Sivakumar V. , Babukannan K. , Biswarup Sen 
Published: March 2014

AbstractAgricultural wastes are excellent carbon materials for adsorption of heavy metal ions from toxic industrial wastewaters. Here we report the biosorption potential of a low cost agricultural waste, Pongamia seed shell (PSS), in the removal of toxic hexavalent Cr, from aqueous synthetic solution. The effect of pH, adsorbent dosage and contact time on the removal of Cr(VI) was studied using batch system. The Cr(VI) removal efficiency was highest at pH 2.0 and adsorbent dosage of 10.0 g/L. A maximum monolayer adsorption capacity of 83.3 mg/g at 30 °C was obtained. Freundlich isotherm model (R2 ≥ 0.95) and pseudo‐second order kinetic model (R2 ≥ 0.99) fitted well with experimental data among the others. The morphology and surface functional groups of the raw PSS and Cr(VI)‐loaded PSS were observed by scanning electron microscopy and Fourier transform infrared spectroscopy, respectively, which confirmed the adsorption and binding of Cr(VI) onto PSS. Experimental and kinetic results suggest PSS as a potential biosorbent of Cr(VI) in industrial wastewaters.
Population pharmacokinetics and pharmacodynamics of rivaroxaban in patients with non‐valvular atrial fibrillation: Results from ROCKET AF
Authors: Girgis I.G. , Patel M.R. , Peters G.R. , Moore K.T. , Mahaffey K.W. , Nessel C.C. , Halperin J.L. , Califf R.M. , Fox K.A.A. , Becker R.C. 
Published: March 2014

AbstractTwo once‐daily rivaroxaban dosing regimens were compared with warfarin for stroke prevention in patients with non‐valvular atrial fibrillation in ROCKET AF: 20 mg for patients with normal/mildly impaired renal function and 15 mg for patients with moderate renal impairment. Rivaroxaban population pharmacokinetic (PK)/pharmacodynamic (PD) modeling data from ROCKET AF patients (n = 161) are reported and are used to confirm established rivaroxaban PK and PK/PD models and to re‐estimate values of the models' parameters for the current AF population. An oral one‐compartment model with first‐order absorption adequately described rivaroxaban PK. Age, renal function, and lean body mass influenced the PK model. Prothrombin time and prothrombinase‐induced clotting time exhibited a near‐linear relationship with rivaroxaban plasma concentration; inhibitory effects were observed through to 24 hours post‐dose. Rivaroxaban plasma concentration and factor Xa activity had an inhibitory maximum‐effect (Emax) relationship. Renal function (on prothrombin time; prothrombinase‐induced clotting time) and age (on factor Xa activity) had moderate effects on PK/PD models. PK and PK/PD models were shown to be adequate for describing the current dataset. These findings confirm the modeling and empirical results that led to the selection of doses tested against warfarin in ROCKET AF.
Changes of seasonal morph development induced by surgical operations in pupae of the large map butterfly Araschnia burejana Bermer (Lepidoptera: Nymphalidae)
Authors: Yamashita Kae , Kanzaki Koji , Hinauchi Mami , Fujishima Tetsuro , Islam Abu Taher Md. Fayezul , Kitazawa Chisato , Endo Katsuhiko , Yamanaka Akira 
Published: March 2014

ABSTRACTThe nymphalid butterfly Araschnia burejana and the papilionid butterfly Papilio xuthus exhibit seasonal diphenism comprising spring‐morphs that develop from diapause pupae and summer‐morphs that develop from non‐diapause pupae. The development of seasonal morphs in A. burejana is regulated by the timing of secretion of ecdysteroids for adult development, whereas that in P. xuthus is regulated by the secretion of summer‐morph‐producing hormone, which is present in the brains and is under control of the photoperiod. We investigated whether a cerebral factor derived from brains plays a significant role in the regulation of seasonal morph development in A. burejana using surgical operations. Pairs of chilled diapause pupae that had been chilled for more than 3 months at 4°C were joined surgically to each other and then developed into spring‐morph or spring‐like‐morph adults. Chilled diapause pupae that were joined with 1‐day‐old non‐diapause pupae developed into summer‐morph or summer‐like‐morph adults. When the brains of non‐diapause pupae were removed surgically 6–8 hr after pupation with and without injection of 20‐hydroxyecdysone, a large portion of them developed into spring‐morph or spring‐like‐morph adults, respectively. Furthermore, 90% of non‐diapause pupae developed into spring‐morph or spring‐like‐morph adults when the neck was ligated within 5 min after pupation. These results indicated that a cerebral factor showing summer‐morph‐producing hormone activity, which is secreted from the brain in the early pupal stage, in addition to 20‐hydroxyecdysone for adult development, play a significant role in the determination of summer‐morph development in non‐diapause pupae of A. burejana. J. Exp. Zool. 321A:276–282, 2014. © 2014 Wiley Periodicals, Inc.
Prevalence of severe obstructive sleep apnea in pediatric adenotonsillectomy patients
Authors: Jiang Nancy , Muhammad Charise , Ho Yan , Del Signore Anthony G. , Sikora Andrew G. , Malkin Benjamin D. 
Published: March 2014

Objectives/HypothesisTo determine the prevalence of severe obstructive sleep apnea (OSA) in a pediatric population who underwent indicated surgery for sleep disordered breathing (SDB).Study DesignRetrospective chart review.MethodsWe reviewed the charts of patients aged 2 to 18 years who underwent tonsillectomy or adenotonsillectomy over a 4‐year period. Indications for preoperative polysomnography (PSG), PSG results, and perioperative complications were recorded.ResultsTwo hundred and thirty‐five patients were included in the final analysis. Of these, 160 patients had preoperative PSG performed. The overall prevalence of severe OSA was 38%. The prevalence in patients for whom preoperative PSG was indicated or for which it should have been advocated according to the American Academy of Otolaryngology—Head and Neck Surgery (AAO‐HNS) clinical practice guideline was 45% and 40%, respectively, whereas the prevalence in patients with no indication for preoperative PSG was 34%. There was no significant difference between groups (P = 0.39). The overall complication rate was 11%, with the rate being significantly lower (P = 0.0022) in patients who did not have preoperative PSG performed (0%) when compared to those who did (16%).ConclusionsThe prevalence of severe OSA in this pediatric population was high. Specifically, a significant percentage of children who would not have received preoperative PSG under the AAO‐HNS recommendations had severe OSA and were consequently admitted for overnight observation. Our results suggest that preoperative PSG should be obtained for all pediatric patients with sleep disordered breathing.Level of Evidence4. Laryngoscope, 124:1975–1978, 2014
Highly Aligned and Single‐Layered Hollow Fibrous Membranes Prepared from Polyurethane and Silica Blends Through a Two‐Fluid Coaxial Electrospun Process
Authors: Huang Yun‐Shao , Kuo Chi‐Ching , Shu Yao‐Chi , Jang Shin‐Cheng , Tsen Wen‐Chin , Chuang Fu‐Sheng , Chen Chien‐Chung 
Published: March 2014

Highly aligned, single‐layered hollow fibrous membranes are prepared using two‐fluid coaxial electrospinning (ES). Polyethylene oxide (PEO) is used as the core, and polyurethane (PU) and blends of PU with silica (SiO2) are used as the shell to extract the PEO. The effects of the polymer‐complex concentration, the ES parameters, and the SiO2 blending ratio on the morphologies and mechanical properties of fibers are explored. Using an appropriate PU concentration and applied spinning voltage combination yields a high fiber‐alignment degree. The hollow fibrous average area increases as the inner‐to‐outer flow‐rate ratio (FRRi/o) increases because the inner flow increases. When using a PU concentration of 13 wt%, a spinning voltage of 7 kV, and an FRRi/o of 0.8, along with blending 15% SiO2 with PU, the fiber alignment of the PU/SiO2 membranes is 95%. The Young's modulus indicates that adding SiO2 enhances the mechanical properties, causing a monolayer hollow‐fiber assembly with interconnected fibers to form.
image
PEG‐Amine‐Initiated Polymerization of Sarcosine N‐Thiocarboxyanhydrides Toward Novel Double‐Hydrophilic PEG‐b‐Polysarcosine Diblock Copolymers
Authors: Tao Xinfeng , Deng Chao , Ling Jun 
Published: March 2014

Amino acid N‐thiocarboxyanhydride (NTA), the thioanalog of N‐carboxyanhydride (NCA), is much more stable than NCA against moisture and heat. The convenient monomer synthesis without rigorous anhydrous requirements makes the ring‐opening polymerization of NTA a competitive alternative to prepare polypeptoid‐containing materials with potential of large‐scale production. Polysarcosines (PSars) with high yields (>90%) and low polydispersities (<1.2) are synthesized from sarcosine N‐thiocarboxyanhydride (Sar‐NTA) at 60 °C initiated by primary amines including poly(ethylene glycol) amine (PEG–NH2). The lengths of PSar segments are controlled by various feed ratios of Sar‐NTA to initiator. PEG‐b‐PSar products, a class of novel double‐hydrophilic diblock copolymers, are effective in stabilizing oil‐in‐water emulsions at nano‐ and microscale, which demonstrates promising encapsulation applications in food, cosmetics, and drug delivery. Due to the different solubility of PEG and PSar blocks, PEG‐b‐PSar copolymers form micelles in organic solvents with the capability to incorporate metal cations including Cu2+ and Ni2+.
image