bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enzymatic Synthesis of High‐Molecular‐Weight Poly(butylene succinate) and its Copolymers
Authors: Ren Liwei , Wang Yushen , Ge Jun , Lu Diannan , Liu Zheng 
Published: January 2015

A two‐step synthesis of high‐molecular‐weight and bio‐based poly(butylene succinate) (PBS) from succinic anhydride and butane‐1,4‐diol is established, in which the first step is a 12 h atmospheric polycondensation at 95 °C in the presence of succinic acid. The subsequent polymerization, catalyzed by Novozym 435 suspended in toluene, yields PBS with a mole­cular weight above 73 000 g mol−1. The recovered lipase catalyst appears to give similar performance after six cycles. The versatility of this atmospheric synthetic route to PBS copolymers is validated through the syntheses of poly(butylene succinate‐co‐butylene malate) (PBSM), poly(butylene succinate‐co‐butylene fumarate) (PBSF), and poly(butylene succinate‐co‐butylene terephthalate) (PBST), in which succinic acid is replaced by corresponding di‐acids as monomers.
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Remodeling of host phosphatidylcholine by Chlamydia acyltransferase is regulated by acyl‐CoA binding protein ACBD6 associated with lipid droplets
Authors: Soupene Eric , Wang Derek , Kuypers Frans A. 
Published: January 2015

AbstractThe bacterial human pathogen Chlamydia trachomatis invades cells as an infectious elementary body (EB). The EB is internalized into a vacuole that is hidden from the host defense mechanism, and is modified to sustain the development of the replicative reticulate body (RB). Inside this parasitophorous compartment, called the inclusion, the pathogen survives supported by an active exchange of nutrients and proteins with the host cell. We show that host lipids are scavenged and modified into bacterial‐specific lipids by the action of a shared human‐bacterial acylation mechanism. The bacterial acylating enzymes for the essential lipids 1‐acyl‐sn‐glycerol 3‐phosphate and 1‐acyl‐sn‐phosphatidylcholine were identified as CT453 and CT775, respectively. Bacterial CT775 was found to be associated with lipid droplets (LDs). During the development of C. trachomatis, the human acyl‐CoA carrier hACBD6 was recruited to cytosolic LDs and translocated into the inclusion. hACBD6 protein modulated the activity of CT775 in an acyl‐CoA dependent fashion and sustained the activity of the bacterial acyltransferase by buffering the concentration of acyl‐CoAs. We propose that disruption of the binding activity of the acyl‐CoA carrier might represent a new drug‐target to prevent growth of C. trachomatis.
A multicomponent T2 relaxometry algorithm for myelin water imaging of the brain
Authors: Björk Marcus , Zachariah Dave , Kullberg Joel , Stoica Petre 
Published: January 2015

PurposeModels based on a sum of damped exponentials occur in many applications, particularly in multicomponent T2 relaxometry. The problem of estimating the relaxation parameters and the corresponding amplitudes is known to be difficult, especially as the number of components increases. In this article, the commonly used non‐negative least squares spectrum approach is compared to a recently published estimation algorithm abbreviated as Exponential Analysis via System Identification using Steiglitz–McBride.MethodsThe two algorithms are evaluated via simulation, and their performance is compared to a statistical benchmark on precision given by the Cramér–Rao bound. By applying the algorithms to an in vivo brain multi‐echo spin‐echo dataset, containing 32 images, estimates of the myelin water fraction are computed.ResultsExponential Analysis via System Identification using Steiglitz–McBride is shown to have superior performance when applied to simulated T2 relaxation data. For the in vivo brain, Exponential Analysis via System Identification using Steiglitz–McBride gives an myelin water fraction map with a more concentrated distribution of myelin water and less noise, compared to non‐negative least squares.ConclusionThe Exponential Analysis via System Identification using Steiglitz–McBride algorithm provides an efficient and user‐parameter‐free alternative to non‐negative least squares for estimating the parameters of multiple relaxation components and gives a new way of estimating the spatial variations of myelin in the brain. Magn Reson Med 75:390–402, 2016. © 2015 Wiley Periodicals, Inc.
Correlation of the loss in photovoltaic module performance with the ageing behaviour of the backsheets used
Authors: Voronko Yuliya , Eder Gabriele C. , Knausz Marlene , Oreski Gernot , Koch Thomas , Berger Karl A. 
Published: January 2015

AbstractThe influence of the type of backsheet on the electrical performance of test modules was evaluated before and after increasing time of accelerated ageing (damp heat [DH] exposure). Besides the measurement of the electrical power of the modules and the performance of the cells by electroluminescence, the ageing‐induced changes within the polymeric encapsulate and backsheets were investigated by means of vibrational spectroscopy and by thermo analytical methods. In addition, the permeability of the backsheets in the original and aged state was determined. This wide set of test parameters and methods allowed for the detection of correlations between (i) physical and chemical properties as well as their ageing‐induced changes of the materials and (ii) the module performance. A clear dependence of the relative loss in power output upon exposure under DH conditions for 2000 h could be observed for a set of identical test modules varied in composition only in the type of back cover used. While the modules containing gas‐tight backsheets and glass experienced only little loss in the relative power output, some modules with permeable backsheets showed a significant relative decrease in the power output and fill factor in dependence of the backsheet type used. Cell degradation could be visualised by recording electroluminescence images before and after the accelerated ageing test. The permeation properties of the backsheet used and their ageing‐induced changes seem to have an influence on the module performance. However, the absolute values neither of the water vapour transmission rate (WVTR) nor of the oxygen transmission rate (OTR) are directly linked to the loss in power output upon accelerated ageing under DH conditions. It could be shown that the ageing‐induced changes (relative transmission rates) between WVTR and OTR can be correlated with the module performance. These ageing‐induced changes in the permeation behaviour of the backsheets can be explained by (i) physical changes (e.g. post‐crystallisation, changes in the crystal structure or the crystalline microstructure) and (ii) chemical ageing effects such as a decrease in the molecular mass of the polyester (PET) polymer chains because of hydrolytic polymer degradation leading to a change in the crystallisation behaviour of PET. Hydrolytic degradation (= chemical ageing) of the PET core layer was observed (with varying extent) for all PET‐based backsheets and can, thus, not be directly correlated with the loss in performance of the corresponding test modules. The physical ageing effects, however, were detected only for those backsheets showing (i) strong deviating changes in the relative permeation rates for oxygen and water vapour upon accelerated ageing and (ii) a clear loss in electrical performance. Copyright © 2015 John Wiley & Sons, Ltd.
Hydrogen exchange of disordered proteins in Escherichia coli
Authors: Smith Austin E. , Zhou Larry Z. , Pielak Gary J. 
Published: January 2015

AbstractA truly disordered protein lacks a stable fold and its backbone amide protons exchange with solvent at rates predicted from studies of unstructured peptides. We have measured the exchange rates of two model disordered proteins, FlgM and α‐synuclein, in buffer and in Escherichia coli using the NMR experiment, SOLEXSY. The rates are similar in buffer and cells and are close to the rates predicted from data on small, unstructured peptides. This result indicates that true disorder can persist inside the crowded cellular interior and that weak interactions between proteins and macromolecules in cells do not necessarily affect intrinsic rates of exchange.
Strength in numbers: quantitative single‐molecule RNA detection assays
Authors: Gaspar Imre , Ephrussi Anne 
Published: January 2015

Gene expression is a fundamental process that underlies development, homeostasis, and behavior of organisms. The fact that it relies on nucleic acid intermediates, which can specifically interact with complementary probes, provides an excellent opportunity for studying the multiple steps—transcription, RNA processing, transport, translation, degradation, and so forth—through which gene function manifests. Over the past three decades, the toolbox of nucleic acid science has expanded tremendously, making high‐precision in situ detection of DNA and RNA possible. This has revealed that many—probably the vast majority of—transcripts are distributed within the cytoplasm or the nucleus in a nonrandom fashion. With the development of microscopy techniques we have learned not only about the qualitative localization of these molecules but also about their absolute numbers with great precision. Single‐molecule techniques for nucleic acid detection have been transforming our views of biology with elementary power: cells are not average members of their population but are highly distinct individuals with greatly and suddenly changing gene expression, and this behavior of theirs can be measured, modeled, and thus predicted and, finally, comprehended. WIREs Dev Biol 2015, 4:135–150. doi: 10.1002/wdev.170This article is categorized under:

Establishment of Spatial and Temporal Patterns > Cytoplasmic Localization
Gene Expression and Transcriptional Hierarchies > Quantitative Methods and Models
Technologies > Analysis of the Transcriptome
Duck species co‐occurrence in hunter daily bags
Authors: Haugen Matthew T. , Vrtiska Mark P. , Powell Larkin A. 
Published: January 2015

ABSTRACTAs multi‐species harvest management gains support among waterfowl managers, increased understanding of duck species relationships during harvest is needed. We used U.S. Fish and Wildlife Service's Parts Collection Survey data from 2002 to 2011 to develop a matrix defining relationships among duck species harvested in the Central Flyway. We calculated conditional probabilities of co‐occurrence in a hunter's daily bag (i.e., P(B|A), the probability that species B was in a hunter bag, given that species A was in the same bag). We then performed 12 scenarios of hypothetical changes to species‐specific regulations. We used Central Flyway harvest estimates from 2011 and probabilities of co‐occurrence to predict the effects of regulatory changes on harvest. Hunters were more likely to harvest 2 species of diving ducks (P(Diving|Diving) = 0.37) than to harvest a diving duck given that a dabbling duck was also harvested the daily bag (P(Diving|Dabbling) = 0.12). Hunters also were more likely to harvest 2 ducks of the same species (and sex in the case of mallards [Anas platyrhynchos]) within a daily bag (mean P(A|A) = 0.31) than 2 ducks of different species (mean P(B|A) = 0.13). Traditionally, managers have focused on single‐species assessments when considering regulatory changes, but harvest regulation changes may affect multiple duck species if harvest is redistributed to other species. Our data show a range of co‐occurrence patterns of species commonly or rarely harvested together. Examination of the relationships among duck species during harvest provides critical insight for the development of appropriate regulations for multi‐species management. © 2015 The Wildlife Society.
Wood products and green chemistry
Authors: Pizzi Antonio 
Published: January 2015

Abstract

Key message

Green chemistry for and from wood has developed numerous industrial products, namely biosourced, green wood adhesives and preservatives, foams, composite matrices, laminates, hard and flexible plastics, flexible films, and abrasive grinding discs, and their number is still growing.

Introduction

This review addresses (1) the elimination of toxic aldehydes from the most common wood panel adhesive, the one based on urea, itself a natural product, (2) biosourced adhesives derived from wood or other vegetable matter and used for wood products, and (3) wood and bark tannin-based foams, natural fiber composites using tannin matrices, paper surface laminates and continuous high-pressure paper laminates using tannin-furanics, hard plastics based on tannin-furanic materials and some of their applications, flexible biosourced tannin-furanic films, and biosourced wood preservatives.
Risk Factors for Development of New or Worsened Pressure Ulcers Among Patients in Inpatient Rehabilitation Facilities in the United States: Data From the Uniform Data System for Medical Rehabilitation
Authors: DiVita Margaret A. , Granger Carl V. , Goldstein Richard , Niewczyk Paulette , Freudenheim Jo L. 
Published: January 2015

AbstractBackgroundDocumentation of a new or worsened pressure ulcer is a new, required quality indicator for all inpatient rehabilitation facilities (IRFs) in the United States; however, there is little research regarding risk factors for pressure ulcers among patients seen in IRFs.ObjectiveTo examine the risk factors for development of a new or worsened pressure ulcer among patients seen in IRFs.DesignA retrospective cohort study.SettingIRFs in the United States.ParticipantsIRF patients more than 18 years of age, with documented new or worsened pressure ulcer during their rehabilitation stay (n = 2766) and IRF patients with no new or worsened pressure ulcer documented from admission to discharge (n = 190,996) discharged October 2008 to September 2011, included in the Uniform Data System for Medical Rehabilitation database.MethodsMultiple logistic regression analysis was used to estimate risk factors for the development of a new or worsened pressure ulcer utilizing data captured in the Centers for Medicare and Medicaid Services (CMS) payment document. Examined were demographic variables, including age and gender, medical variables, including impairment type and presence of comorbidities, and functional status, as measured through the Functional Independence Measure (FIM) instrument.Main Outcome MeasuresDevelopment of a new or worsened pressure ulcer in patients during the rehabilitation stay compared to patients with no documented pressure ulcer or no worsened ulcer.ResultsAdmission FIM total was strongly associated with development of a new or worsened pressure ulcer, P <.001 in analyses of all patients and for each of the 3 impairment‐specific groups with the highest rate of ulcer development among spinal cord injury, orthopedic, and amputation cases. CMS comorbidity tier was also significantly associated with ulcers in all models. Other variables that entered one or more models included increased age, male gender, and use of a wheelchair.ConclusionsAdmission FIM total and CMS comorbidity tier may be useful in the identification of patients at risk for development of new or worsened pressure ulcers in IRFs. Identification of pressure ulcer risk factors has important implications for individual plan‐of‐care decisions as well as for resource provisions during the rehabilitation stay.
Induced lung inflammation and dietary protein supply affect nitrogen retention and amino acid metabolism in growing pigs
Authors: Kampman-van de Hoek Esther , Sakkas Panagiotis , Gerrits Walter J. J. , van den Borne Joost J. G. C. , van der Peet-Schwering Carola M. C. , Jansman Alfons J. M. 
Published: January 2015

It is hypothesised that during immune system activation, there is a competition for amino acids (AA) between body protein deposition and immune system functioning. The aim of the present study was to quantify the effect of immune system activation on N retention and AA metabolism in growing pigs, depending on dietary protein supply. A total of sixteen barrows received an adequate (Ad) or restricted (Res) amount of dietary protein, and were challenged at day 0 with intravenous complete Freund's adjuvant (CFA). At days − 5, 3 and 8, an irreversible loss rate (ILR) of eight AA was determined. CFA successfully activated the immune system, as indicated by a 2- to 4-fold increase in serum concentrations of acute-phase proteins (APP). Pre-challenge C-reactive protein concentrations were lower (P< 0·05) and pre- and post-challenge albumin tended to be lower in Res-pigs. These findings indicate that a restricted protein supply can limit the acute-phase response. CFA increased urinary N losses (P= 0·04) and tended to reduce N retention in Ad-pigs, but not in Res-pigs (P= 0·07). The ILR for Val was lower (P= 0·05) at day 8 than at day 3 in the post-challenge period. The ILR of most AA, except for Trp, were strongly affected by dietary protein supply and positively correlated with N retention. The correlations between the ILR and APP indices were absent or negative, indicating that changes in AA utilisation for APP synthesis were either not substantial or more likely outweighed by a decrease in muscle protein synthesis during immune system activation in growing pigs.
Interplay of weak interactions in the atom-by-atom condensation of xenon within quantum boxes
Authors: Nowakowska Sylwia , Wäckerlin Aneliia , Kawai Shigeki , Ivas Toni , Nowakowski Jan , Fatayer Shadi , Wäckerlin Christian , Nijs Thomas , Meyer Ernst , Björk Jonas , Stöhr Meike , Gade Lutz H. , Jung Thomas A. 
Published: January 2015

AbstractCondensation processes are of key importance in nature and play a fundamental role in chemistry and physics. Owing to size effects at the nanoscale, it is conceptually desired to experimentally probe the dependence of condensate structure on the number of constituents one by one. Here we present an approach to study a condensation process atom-by-atom with the scanning tunnelling microscope, which provides a direct real-space access with atomic precision to the aggregates formed in atomically defined ‘quantum boxes’. Our analysis reveals the subtle interplay of competing directional and nondirectional interactions in the emergence of structure and provides unprecedented input for the structural comparison with quantum mechanical models. This approach focuses on—but is not limited to—the model case of xenon condensation and goes significantly beyond the well-established statistical size analysis of clusters in atomic or molecular beams by mass spectrometry.
Modification of perpendicular magnetic anisotropy and domain wall velocity in Pt/Co/Pt by voltage-induced strain
Authors: Shepley P. M. , Rushforth A. W. , Wang M. , Burnell G. , Moore T. A. 
Published: January 2015

AbstractThe perpendicular magnetic anisotropy Keff, magnetization reversal and field-driven domain wall velocity in the creep regime are modified in Pt/Co(0.85–1.0 nm)/Pt thin films by strain applied via piezoelectric transducers. Keff, measured by the extraordinary Hall effect, is reduced by 10 kJ/m3 by tensile strain out-of-plane εz = 9 × 10−4, independently of the film thickness, indicating a dominant volume contribution to the magnetostriction. The same strain reduces the coercive field by 2–4 Oe and increases the domain wall velocity measured by wide-field Kerr microscopy by 30-100%, with larger changes observed for thicker Co layers. We consider how strain-induced changes in the perpendicular magnetic anisotropy can modify the coercive field and domain wall velocity.
Fish oil supplements in New Zealand are highly oxidised and do not meet label content of n-3 PUFA
Authors: Albert Benjamin B. , Derraik José G. B. , Cameron-Smith David , Hofman Paul L. , Tumanov Sergey , Villas-Boas Silas G. , Garg Manohar L. , Cutfield Wayne S. 
Published: January 2015

AbstractWe evaluated the quality and content of fish oil supplements in New Zealand. All encapsulated fish oil supplements marketed in New Zealand were eligible for inclusion. Fatty acid content was measured by gas chromatography. Peroxide values (PV) and anisidine values (AV) were measured and total oxidation values (Totox) calculated. Only 3 of 32 fish oil supplements contained quantities of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) that were equal or higher than labelled content, with most products tested (69%) containing <67%. The vast majority of supplements exceeded recommended levels of oxidation markers. 83% products exceeded the recommended PV levels, 25% exceeded AV thresholds and 50% exceeded recommended Totox levels. Only 8% met the international recommendations, not exceeding any of these indices. Almost all fish oil supplements available in the New Zealand market contain concentrations of EPA and DHA considerably lower than claimed by labels. Importantly, the majority of supplements tested exceeded the recommended indices of oxidative markers. Surprisingly, best-before date, cost, country of origin and exclusivity were all poor markers of supplement quality.
Role of Cys3602 in the function and regulation of the cardiac ryanodine receptor
Authors: Mi Tao , Xiao Zhichao , Guo Wenting , Tang Yijun , Hiess Florian , Xiao Jianmin , Wang Yundi , Zhang Joe Z. , Zhang Lin , Wang Ruiwu , Jones Peter P. , Chen S. R. Wayne 
Published: January 2015

The cardiac Ca2+ release channel [ryanodine receptor type 2 (RyR2)] is modulated by thiol reactive agents, but the molecular basis of RyR2 modulation by thiol reagents is poorly understood. Cys3635 in the skeletal muscle RyR1 is one of the most hyper-reactive thiols and is important for the redox and calmodulin (CaM) regulation of the RyR1 channel. However, little is known about the role of the corresponding cysteine residue in RyR2 (Cys3602) in the function and regulation of the RyR2 channel. In the present study, we assessed the impact of mutating Cys3602 (C3602A) on store overload-induced Ca2+ release (SOICR) and the regulation of RyR2 by thiol reagents and CaM. We found that the C3602A mutation suppressed SOICR by raising the activation threshold and delayed the termination of Ca2+ release by reducing the termination threshold. As a result, C3602A markedly increased the fractional Ca2+ release. Furthermore, the C3602A mutation diminished the inhibitory effect of N-ethylmaleimide on Ca2+ release, but it had no effect on the stimulatory action of 4,4′-dithiodipyridine (DTDP) on Ca2+ release. In addition, Cys3602 mutations (C3602A or C3602R) did not abolish the effect of CaM on Ca2+-release termination. Therefore, RyR2–Cys3602 is a major site mediating the action of thiol alkylating agent N-ethylmaleimide, but not the action of the oxidant DTDP. Our data also indicate that residue Cys3602 plays an important role in the activation and termination of Ca2+ release, but it is not essential for CaM regulation of RyR2.
Asymmetrical effects of unilateral right or left amygdala damage on auditory cortical processing of vocal emotions
Authors: Frühholz Sascha , Hofstetter Christoph , Cristinzio Chiara , Saj Arnaud , Seeck Margitta , Vuilleumier Patrik , Grandjean Didier 
Published: January 2015

Significance
The human voice is a major source for auditorily communicated social signals. The voice in general, and emotional cues embedded in vocalizations in particular, receive enhanced decoding in sensory cortical areas of the auditory system. This enhanced cortical decoding is assumed to be remotely driven by the amygdala, which responds to socially and emotionally meaningful stimuli. Here, we tested for the first time, to our knowledge, how damage to either the left or right amygdala impairs the cortical processing of human voices and vocal affect. Amygdala damage generally leads to reduced cortical processing of human voices in the hemisphere corresponding to the side of the amygdala damage, whereas only left amygdala damage impaired the cortical processing of vocal affect.