bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of 13C enrichment and sugar type on analysis of sugars by gas chromatography/combustion/isotope ratio mass spectrometry
Authors: Baumann Karen , Dignac Marie‐France , Bardoux Gérard , Rumpel Cornelia 
Published: July 2012

RATIONALEThe objective of this investigation was to test gas‐chromatographic compound‐specific analysis for studies on the isotopic composition of 13C‐enriched sugar molecules. The effects of 13C enrichment and type of sugar (C5, C6) will provide valuable information on isotopic correction for future studies employing 13C‐enriched sugars.METHODSFive sugar solutions of xylose, mannose and glucose with 13C enrichments ranging between 1.1 and 1.5 atom‐% were prepared. The 13C enrichments of the initial sugars were measured by elemental analyser/isotope ratio mass spectrometry (EA/IRMS); 13C enrichments for derivatised sugars were obtained by gas chromatography/combustion/IRMS (GC/C/IRMS).RESULTSThe linear relationships between the 13C enrichments of the initial sugars and the values for the derivatised sugars were sugar‐type dependent. Corrections for GC/C/IRMS values took into account the kinetic isotope effect (KIE) of the derivatising agent associated with the coefficient (Kd) and a newly introduced second coefficient (Kc) associated with the KIE of the sugar. While Kd was constant, Kc varied with sugar type. During derivatisation acetate groups with 12C and sugars with more 13C reacted faster.CONCLUSIONSCoefficients for the specific ranges of 13C enrichments under study have to be assessed and the reactions of different sugar types have to be taken into account to avoid underestimation of 13C enrichment of up to 9% (C5) or overestimation of up to 4% (C6). Copyright © 2012 John Wiley & Sons, Ltd.
Skew‐elliptical spatial random effect modeling for areal data with application to mapping health utilization rates
Authors: Nathoo Farouk S. , Ghosh Pulak 
Published: July 2012

Mixed models incorporating spatially correlated random effects are often used for the analysis of areal data. In this setting, spatial smoothing is introduced at the second stage of a hierarchical framework, and this smoothing is often based on a latent Gaussian Markov random field. The Markov random field provides a computationally convenient framework for modeling spatial dependence; however, the Gaussian assumption underlying commonly used models can be overly restrictive in some applications. This can be a problem in the presence of outliers or discontinuities in the underlying spatial surface, and in such settings, models based on non‐Gaussian spatial random effects are useful.Motivated by a study examining geographic variation in the treatment of acute coronary syndrome, we develop a robust model for smoothing small‐area health service utilization rates. The model incorporates non‐Gaussian spatial random effects, and we develop a formulation for skew‐elliptical areal spatial models. We generalize the Gaussian conditional autoregressive model to the non‐Gaussian case, allowing for asymmetric skew‐elliptical marginal distributions having flexible tail behavior. The resulting new models are flexible, computationally manageable, and can be implemented in the standard Bayesian software WinBUGS. We demonstrate performance of the proposed methods and comparisons with other commonly used Gaussian and non‐Gaussian spatial prior formulations through simulation and analysis in our motivating application, mapping rates of revascularization for patients diagnosed with acute coronary syndrome in Quebec, Canada. Copyright © 2012 John Wiley & Sons, Ltd.
Characterization of Differential Toll‐like Receptor Responses below the Optical Diffraction Limit
Authors: Aaron Jesse S. , Carson Bryan D. , Timlin Jerilyn A. 
Published: July 2012

AbstractMany membrane receptors are recruited to specific cell surface domains to form nanoscale clusters upon ligand activation. This step appears to be necessary to initiate cell signaling, including pathways in innate immune system activation. However, virulent pathogens such asYersinia pestis(the causative agent of plague) are known to evade innate immune detection, in contrast to similar microbes (such asEscherichia coli) that elicit a robust response. This disparity has been partly attributed to the structure of lipopolysaccharides (LPS) on the bacterial cell wall, which are recognized by the innate immune receptor TLR4. It is hypothesized that nanoscale differences exist between the spatial clustering of TLR4 upon binding of LPS derived fromY. pestisandE. coli. Although optical imaging can provide exquisite details of the spatial organization of biomolecules, there is a mismatch between the scale at which receptor clustering occurs (<300 nm) and the optical diffraction limit (>400 nm). The last decade has seen the emergence of super‐resolution imaging methods that effectively break the optical diffraction barrier to yield truly nanoscale information in intact biological samples. This study reports the first visualizations of TLR4 distributions on intact cells at image resolutions of <30 nm using a novel, dual‐color stochastic optical reconstruction microscopy (STORM) technique. This methodology permits distinction between receptors containing bound LPS from those without at the nanoscale. Importantly, it is also shown that LPS derived from immunostimulatory bacteria result in significantly higher LPS–TLR4 cluster sizes and a nearly twofold greater ligand/receptor colocalization as compared to immunoevading LPS.
Revisiting patient safety for innovative urological surgery
Authors: Ahmed Kamran , Sharma Sonia , Khan Shahid A.A. , Cahill Declan , Kumar Pardeep , Challacombe Ben , Kirby Roger , Khan Mohammed Shamim , Dasgupta Prokar 
Published: July 2012

AbstractTechnological advances in urology have led to many beneficial outcomes for patients. Unfortunately, increasing the complexity of a procedure may make surgical interventions even more unpredictable, increasing the possibility of error, with its detrimental effect on patient safety. In this article, the authors highlight the fundamental components of the patient safety process and recommend measures to maintain and enhance safer patient care. Copyright © 2012 John Wiley & Sons
Effects of multi‐walled carbon nanotube functionalization on the morphological and mechanical properties of nanocomposite foams based on poly(vinyl chloride)/(wood flour)/ (multi‐walled carbon nanotubes)
Authors: Ghasemi I. , Farsheh A.T. , Masoomi Z. 
Published: July 2012

AbstractExperimental results are presented for nanocomposite foams based on unplasticized poly(vinyl chloride)/(wood flour)/(multi‐wall carbon nanotubes) (PVC/WF/MWCNTs). The nanocomposite samples were prepared in an internal mixer and foamed via a batch processing method using compression molding. Nanoparticles were functionalized by sodium hypochlorite solution, and the functionalization process was monitored by Fourier‐transform infrared spectroscopy. The effects of MWCNTs (both neat and functionalized) and blowing agent concentration on the morphological properties (cell size and cell density) and mechanical properties (tensile and flexural strength) of the foam samples were studied. The results revealed that foam cell sizes decreased and cell densities increased with addition of MWCNTs. The dispersion of nanoparticles in the PVC medium was increased by functionalization, and the morphological properties of the foams containing functionalized nanoparticles were improved. Density of nanocomposite foams decreased more with functionalized MWCNTs as compared to other samples. Chemical blowing agent concentration had no significant effect on sample density. Mechanical properties of the samples were improved by using functionalized MWCNTs in comparison with those of foams without this component. J. VINYL ADDIT. TECHNOL., 18:161–167, 2012. © 2012 Society of Plastics Engineers
The role of spatial planning in adapting to climate change
Authors: Hurlimann Anna C. , March Alan P. 
Published: July 2012

AbstractSpatial planning has been identified as a critical mechanism through which climate change adaptation can be facilitated. We review the role of spatial planning as a tool for adaptation to climate change. In doing so, we describe common planning processes and tools. Six capacities of spatial planning that have the potential ability to facilitate climate change adaptation are identified and discussed. These principally relate to spatial planning's ability to: act on matters of collective concern; manage competing interests; cut across scales; reduce and act on uncertainty; act as a knowledge repository; and be oriented to the future while integrating a range of diverse systems. Methods (tools) for planning which have the capacity to address climate change adaptation are presented and discussed. In light of these capacities and acknowledged limitations in planning practice, we identify three key challenges to spatial planning for adaptation: (1) developing conviction; (2) facilitating equitable processes and outcomes; and (3) transforming planning systems from passive to proactive.WIREs Clim Change2012 doi: 10.1002/wcc.183This article is categorized under:Vulnerability and Adaptation to Climate Change > Institutions for Adaptation
A view of microgrids
Authors: Lopes João Abel Peças , Madureira André Guimarães , Moreira Carlos Coelho Leal Monteiro 
Published: July 2012

AbstractLarge‐scale integration of distributed energy resources in low voltage distribution grids will have a serious impact on power system operation. The development of the microgrid concept is presented as a solution to overcome some of the negative impacts of massive microgeneration deployment. It has paved the way for an active network management approach within the smart grid paradigm. The microgrid concept is able to address the integration of geographically dispersed energy resources, thus avoiding significant technical problems that may affect the security of operation.This article is categorized under:

Energy Infrastructure > Systems and Infrastructure
Energy Systems Economics > Climate and Environment
Energy and Development > Systems and Infrastructure
Loss of a condyle of the femur or tibia following septic arthritis in infancy: Problems of management and testing of a hypothesis of pathogenesis
Authors: Tercier Stéphane , Siddesh N. D. , Shah Hitesh , Girisha K. M. , Joseph Benjamin 
Published: July 2012

Purpose The study was undertaken to: (1) describe the characteristic radiological features and problems of management of the loss of one condyle of the femur or tibia following septic arthritis of the knee in infancy and (2) test a hypothesis of the cause of the loss of a single condyle. Methods Radiographs of eight children with the loss of one condyle of the femur or the tibia following septic arthritis in infancy were reviewed. The course and outcome in two of these children who underwent reconstructive operations were studied. The knees of 35 stillborn foetuses were dissected to determine if the presence of synovial septae could account for the isolated loss of one condyle following infection. Results All eight cases showed characteristic features of loss of half the epiphysis, the underlying physis and part of the adjacent metaphysis; the other condyle was totally spared. The two children who underwent elaborate reconstructive procedures had poor outcomes at skeletal maturity, despite a series of additional operations. The foetal cadaveric study showed that complete infrapatellar synovial septae are present in some foetuses approaching 40 weeks of gestation. Conclusions The pattern of loss of a femoral or tibial condyle following septic arthritis is consistent with total preservation of the other condyle. The outcome of surgical reconstruction of the missing condyle is poor. The presence of a complete synovial septum could result in the localisation of infection to one half of the joint, with the destruction of one condyle.
The fluid dynamics of rolling wheels at low Reynolds number
Authors: Pirozzoli Sergio , Orlandi Paolo , Bernardini Matteo 
Published: July 2012

AbstractWe study the fluid dynamics of rolling wheels at Reynolds number ${\mathit{Re}}_{D} \leq 1000$ (where ${\mathit{Re}}_{D} $ is the Reynolds number based on the wheel diameter), with the objective of characterizing the various regimes of steady and unsteady motion. Regardless of the Reynolds number, the flow is found to separate approximately $1{0}^{\ensuremath{\circ} } $ upstream of the apex of the wheel, where a saddle point in the pseudo-streamtrace pattern is observed. Under the flow conditions here essayed, the drag coefficient steadily decreases with ${\mathit{Re}}_{D} $, and the lift coefficient remains strictly positive. The positive lift provided by the rolling wheel is associated with the presence of a strong (positive) peak of the static pressure in the upstream proximity of the contact point with the ground, which we interpret as the result of the impingement of flow particles entrained in the boundary layer that develops on the front part of the wheel. Steady laminar flow is observed up to ${\mathit{Re}}_{D} \approx 300$, which is characterized by a three-dimensional wake whose length increases with the Reynolds number. Unsteadiness is first observed at ${\mathit{Re}}_{D} \approx 400$, under which conditions the flow retains planar symmetry, and is characterized by the quasi-periodic shedding of hairpin vortices. Transition to three-dimensional flow happens at ${\mathit{Re}}_{D} \approx 500$, in which case a sinuous mode of instability in the wheel wake is established, which modulates the shedding of the hairpins, and which causes the onset of a non-zero side force. At the highest Reynolds number considered here (${\mathit{Re}}_{D} = 1000$) the wake exhibits some characters of turbulence, with wide-band frequency spectra, and its topology entirely changes, becoming split into two parts, and being much shortened compared to the lower-${\mathit{Re}}_{D} $ cases. Despite the limitation of the study to low Reynolds numbers we find that, once significant three-dimensionality and scale separation are established in the wheel wake, the nature of the flow becomes qualitatively similar to fully developed turbulent flow. In perspective, this observation opens interesting avenues for the prediction of unsteady flow around rotating tyres at moderate computational cost.
The appearance of boundary layers and drift flows due to high-frequency surface waves
Authors: Manor Ofer , Yeo Leslie Y. , Friend James R. 
Published: July 2012

AbstractThe classical Schlichting boundary layer theory is extended to account for the excitation of generalized surface waves in the frequency and velocity amplitude range commonly used in microfluidic applications, including Rayleigh and Sezawa surface waves and Lamb, flexural and surface-skimming bulk waves. These waves possess longitudinal and transverse displacements of similar magnitude along the boundary, often spatiotemporally out of phase, giving rise to a periodic flow shown to consist of a superposition of classical Schlichting streaming and uniaxial flow that have no net influence on the flow over a long period of time. Correcting the velocity field for weak but significant inertial effects results in a non-vanishing steady component, a drift flow, itself sensitive to both the amplitude and phase (prograde or retrograde) of the surface acoustic wave propagating along the boundary. We validate the proposed theory with experimental observations of colloidal pattern assembly in microchannels filled with dilute particle suspensions to show the complexity of the boundary layer, and suggest an asymptotic slip boundary condition for bulk flow in microfluidic applications that are actuated by surface waves.
A common haplotype of carnitine palmitoyltransferase 1b is associated with the metabolic syndrome
Authors: Auinger A. , Rubin D. , Sabandal M. , Helwig U. , Rüther A. , Schreiber S. , Foelsch U. R. , Döring F. , Schrezenmeir J. 
Published: July 2012

The carnitine palmitoyltransferase (CPT) enzyme system facilitates the transport of long-chain fatty acids into mitochondria to provide substrates for β-oxidation. We performed an analysis including three coding SNP in the muscle isoform of the CPT1b gene (rs3213445, rs2269383 and rs470117) and one coding SNP in the CPT2 gene (rs1799821) to find associations with traits of the metabolic syndrome (MetS). Male participants (n755) from the Metabolic Intervention Cohort Kiel were genotyped and phenotyped for features of the MetS. Participants underwent a glucose tolerance test and a postprandial assessment of metabolic variables after a standardised mixed meal. Carriers of the rare CPT1b 66V (rs3213445) allele had significantly higher γ-glutamyl transpeptidase (GGT), glutamic oxaloacetic transaminase (GOT) and glutamic pyruvate transaminase (GPT) activities (P< 0·0001,P= 0·03 andP= 0·048, respectively) and a higher fatty liver index (FLI,P= 0·026). Fasting and postprandial TAG (P= 0·007 andP= 0·009, respectively) and fasting glucose (P= 0·012) were significantly higher in 66V-allele carriers. The insulin sensitivity index determined after a glucose load was lower in those subjects (P= 0·005). Total cholesterol (P= 0·051) and LDL-cholesterol (P= 0·062) tended to be higher in 66V-allele carriers when compared with I66I homozygotes. Homozygosity of the rare K531E allele presented with lower GGT and GOT activities (P= 0·011 andP= 0·027, respectively). E531E homozygotes tended to have lower GPT and FLI (P= 0·078 andP= 0·052, respectively). CPT2 V368I (rs1799821) genotypic groups did not differ in the investigated anthropometric and metabolic parameters. The present results confirm the association of CPT1b coding polymorphisms with the MetS, with a deleterious effect of the CPT1b I66V and a protective impact of the CPT1b K531E SNP, whereas haplotype analysis indicates a relevance of the E531K polymorphism only.
Parasite diversity and microsatellite variability in native and introduced populations of fourNeogobiusspecies (Gobiidae)
Authors: ONDRAČKOVÁ M. , ŠIMKOVÁ A. , CIVÁŇOVÁ K. , VYSKOČILOVÁ M. , JURAJDA P. 
Published: July 2012

SUMMARYSpecies introduced into new areas often show a reduction in parasite and genetic diversity associated to the limited number of founding individuals. In this study, we compared microsatellite and parasite diversity in both native (lower Danube) and introduced populations of 4 Ponto-Caspian gobies, including those (1) introduced from within the same river system (middle Danube;Neogobius kessleriandN. melanostomus), and (2) introduced from a different river system (River Vistula;N. fluviatilisandN. gymnotrachelus). Microsatellite data confirmed the lower Danube as a source population for gobies introduced into the middle Danube. Both native and introduced (same river system) populations ofN. kessleriandN. melanostomushad comparable parasite species richness and microsatellite diversity, possibly due to multiple and/or continual migration/introduction of new individuals and the acquisition of local parasites. Reduced parasite species richness and microsatellite diversity were observed in introduced (different river system) populations in the Vistula. A low number of colonists found forN. fluviatilisandN. gymnotrachelusin the Vistula potentially resulted in reduced introduction of parasite species. Insufficient adaptation of the introduced host to local parasite fauna, together with introduction into an historically different drainage system, may also have contributed to the reduced parasite fauna.
Lipopolysaccharide-induced modulation in the expression of progesterone receptor and estradiol receptor leads to early pregnancy loss in mouse
Authors: Agrawal Varkha , Jaiswal Mukesh Kumar , Jaiswal Yogesh Kumar 
Published: July 2012

SummaryThe objective of the present study was to investigate the effect of Gram-negative bacteria infection on ovarian steroid receptors, i.e. progesterone receptor (PR) and estradiol receptor (ER) during preimplantation days of pregnancy. A well established mouse model of Gram-negative bacteria infection was used to test this objective. Mice were treated with normal saline or lipopolysaccharide (LPS) on day 0.5 of pregnancy and used to collect embryos and uterine horns on day 1.5 to day 4.42 preimplantation day of pregnancy. Total RNA was extracted and reverse-transcription polymerase chain reaction (PCR) was performed to check the expression of PR and ER genes. The mRNA expression of PR and ER was altered in embryos and uterus of LPS-treated animals during preimplantation days of pregnancy studied. These results suggest that PR and ER play an important role in Gram-negative bacteria infection and induced implantation failure in mouse.
Structural, mechanistic and regulatory studies of serine palmitoyltransferase
Authors: Lowther Jonathan , Naismith James H. , Dunn Teresa M. , Campopiano Dominic J. 
Published: July 2012

SLs (sphingolipids) are composed of fatty acids and a polar head group derived from L-serine. SLs are essential components of all eukaryotic and many prokaryotic membranes but S1P (sphingosine 1-phosphate) is also a potent signalling molecule. Recent efforts have sought to inventory the large and chemically complex family of SLs (LIPID MAPS Consortium). Detailed understanding of SL metabolism may lead to therapeutic agents specifically directed at SL targets. We have studied the enzymes involved in SL biosynthesis; later stages are species-specific, but all core SLs are synthesized from the condensation of L-serine and a fatty acid thioester such as palmitoyl-CoA that is catalysed by SPT (serine palmitoyltransferase). SPT is a PLP (pyridoxal 5′-phosphate)-dependent enzyme that forms 3-KDS (3-ketodihydrosphingosine) through a decarboxylative Claisen-like condensation reaction. Eukaryotic SPTs are membrane-bound multi-subunit enzymes, whereas bacterial enzymes are cytoplasmic homodimers. We use bacterial SPTs (e.g. from Sphingomonas) to probe their structure and mechanism. Mutations in human SPT cause a neuropathy [HSAN1 (hereditary sensory and autonomic neuropathy type 1)], a rare SL metabolic disease. How these mutations perturb SPT activity is subtle and bacterial SPT mimics of HSAN1 mutants affect the enzyme activity and structure of the SPT dimer. We have also explored SPT inhibition using various inhibitors (e.g. cycloserine). A number of new subunits and regulatory proteins that have a direct impact on the activity of eukaryotic SPTs have recently been discovered. Knowledge gained from bacterial SPTs sheds some light on the more complex mammalian systems. In the present paper, we review historical aspects of the area and highlight recent key developments.
Switchgrass - practical issues in developing a fuel crop.
Authors: Shastri Y. N. , Hansen A. C. , Rodriguez L. F. , Ting K. C. 
Published: July 2012

Abstract
The biomass-based energy sector will play an important role in our drive towards renewable energy. Switchgrass has been identified as one of the candidate-dedicated energy crops in the USA because of its various desirable traits. However, many challenges still exist in ensuring a commercially viable switchgrass crop that is sustainable and techno-economically feasible. This article reviews the existing literature to highlight those challenges and potential solutions and recommendations to address those in the future. Various stages in the switchgrass-based biofuel system, namely crop production, provision and logistics, and conversion, are analysed. For each of these stages, the important challenges as reported in the literature are mentioned, and research gaps are identified. The systems-level issues as well as the challenges associated with the practical implementation of switchgrass production are also highlighted. The review illustrates that although switchgrass is a viable biofuel feedstock, considerable progress is necessary to achieve large-scale practical success.