bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemical Composition Distribution and Temperature Rising Elution Fractionation of Linear Olefin Block Copolymers
Authors: Anantawaraskul Siripon , Sottesakul Suwicha , Siriwongsarn Ekaphol , Soares João B.P. 
Published: August 2013

SummaryLinear olefin block copolymers (OBCs) have statistical multi‐block structures and exhibit unique properties that are different from those of other polyolefin elastomers. In this work, the microstructure details of OBCs were investigated using a Monte Carlo model. Theoretical TREF profiles for these materials were simulated using a modified version of the TREF model previously developed in our group. Effects of polymerization parameters on OBC microstructures and TREF profiles were investigated. Distinctions among chemical composition distribution, longest ethylene sequence distribution, and TREF profiles were observed and discussed.
Optimum Cr(acac)3 Concentration for NMR Quantitative Analysis of Polyolefins
Authors: Zhou Zhe , He Yiyong , Qiu Xiaohua , Redwine David , Potter Janece , Cong Rongjuan , Miller Matthew 
Published: August 2013

SummaryOlefin copolymers are major industry products. 13C NMR is a critical analytical tool to characterize the composition as well as the monomer sequence distribution. Due to the low natural abundance, small magnetogyric ratio and long spin lattice relaxation time (T1) of 13C, a large number of scans are needed to obtain reasonable signal‐to‐noise (S/N) for quantitative analyses. This needs a significant amount of NMR time. A relaxation reagent, such as Cr(acac)3, can reduce the T1 and abolish unwanted NOE. Based on the effect of Cr(acac)3 on 13C T1 and line width of HDPE and an ethylene‐octene copolymer, 0.025M Cr(acac)3 is recommended for routine 13C NMR experiments and 0.05 M Cr(acac)3 can be used with less stringent resolution requirements. The end‐group and unsaturation analysis of polyolefins by 1H NMR is complicated by three factors: 1) Low signal level; 2) Significant and anomalous molecular weight and concentration dependences for the 1H T1; 3) Sample degradation induced by long acquisition time. To solve these problems, Cr(acac)3 can be added to reduce the 1H T1, hence NMR instrument time. By the systematic study of the effect of Cr(acac)3 on the 1H T1 and spectrum quality, the optimum Cr(acac)3 concentration was found to be 0.001 M, at which concentration, the longest 1H T1 of polyolefins is reduced by about a factor of 4, while retaining almost the same spectral quality. Sample degradation is also avoided due to much shorter acquisition time. This provides a robust and efficient procedure for characterizing parts‐per‐million level unsaturated structures and end‐groups in polyolefins.
Simultaneous Deconvolution of MWD and CCD of Ethylene/1‐Olefin Copolymers Using Genetic Algorithm
Authors: Nanthapoolsub Uthane , Anantawaraskul Siripon , Saengkhamkhom Khomwat 
Published: August 2013

SummaryMultiple‐site‐type catalytic systems produce ethylene/1‐olefin copolymers with broad molecular weight distribution (MWD) and chemical composition distribution (CCD) because each active site type produces chains with distinct chain microstructures. Simultaneous deconvolution of the MWD and CCD can be used to identify the number of active site types and chain microstructures produced on each active site type by performing parameter estimation to minimize the sum of the squares of differences between experimental and model data. However, conventional optimization algorithms often rely on the adequate initial guess. In this work, a genetic algorithm, which is a stochastic optimization search heuristic that mimics the natural evolution process, was implemented during the simultaneous deconvolution. The proposed approach was validated with simulated data of model ethylene/1‐butene copolymers produced using a system with three active site types.
Advances in Thermal Gradient Interaction Chromatography and Crystallization Techniques for Composition Analysis in Polyolefins
Authors: Monrabal Benjamin , López Esther , Romero Loli 
Published: August 2013

SummarySince the introduction of high temperature interaction chromatography for the analysis of polyolefins the technique has demanded a particular interest in the analysis of elastomers where crystallization techniques will meet a limitation given the low crystallinity of these polymers. In this paper the introduction of non carbon adsorption supports such as molybdenum sulfide, boron nitride and tungsten sulfide with equivalent separation to graphitized carbon packing in TGIC analysis of polyolefins is presented. A mechanism for the separation of polyolefins by adsorption chromatography on layered substrates is proposed. The influence of solvent polarity in interaction chromatography is discussed.
Diet‐induced obesity alters immune cell infiltration and expression of inflammatory cytokine genes in mouse ovarian and peri‐ovarian adipose depot tissues
Authors: Nteeba J. , Ortinau L.C. , Perfield J.W. , Keating A.F. 
Published: August 2013

SUMMARYDysregulation of immune cells and/or altered inflammatory signaling have been implicated with reproductive dysfunction. Physiological changes leading to perturbations in the profile of immune cells and/or pro‐inflammatory cytokines in or around female reproductive tissue could potentially have profound effects on ovarian function. Obesity is associated with chronic low‐grade inflammation due, in part, to increased immune cell infiltration and inflammation in visceral adipose depots. This study investigated the impact of diet‐induced obesity on immune cell infiltration and inflammation in peri‐ovarian adipose tissue and mRNA expression of key inflammatory markers and microRNAs (miRs) in ovarian tissue. Six‐week‐old female C57Bl/6J mice were fed a standard chow or high‐fat diet (HFD; 60% kcal fat) for approximately 7 months, at which time peri‐ovarian adipose tissue and ovarian tissues were collected. Histological analysis of peri‐ovarian adipose tissue from obese mice revealed increased (P < 0.05) adipocyte size and the presence of crown‐like structures, the morphological presentation of infiltrating immune cells in adipose tissue, along with increases (P < 0.05) in the mRNA levels of markers of T‐cells, activated macrophages, inflammatory cytokines, and chemokines. Ovarian mRNA levels of Il1b, Il6, Tnfa, p55, p75, Ccl2, Ikbkb, and Rela were higher in obese tissue (P < 0.05), with a strong trend (P = 0.06) for an increase in Nos2 and RELA protein. Additionally, ovarian miR125b and miR143 levels were decreased (P = 0.1). These data demonstrate that diet‐induced obesity elevates expression of inflammatory‐mediator genes in both the ovary and surrounding adipose depot, potentially negatively affecting ovarian function. Mol. Reprod. Dev. 80: 948–958, 2013. © 2013 Wiley Periodicals, Inc.
Simulation of damage–permeability coupling for mortar under dynamic loads
Authors: Chen Wen , La Borderie Christian , Maurel Olivier , Pijaudier‐Cabot Gilles , Rey‐Bethbeder Franck 
Published: August 2013

SUMMARYThe results reported in this paper deal with the simulation of damage in cohesive geomaterials such as rocks or concrete subjected to dynamic loads. The practical objective is to stimulate the production of tight gas reservoirs with a technique that is an alternative to hydraulic fracturing. The principle is that when subjected to dynamic loads, cohesive materials such as concrete, rocks or ceramics exhibit distributed micro‐cracking as opposed to localised cracking observed under static loads. Hence, a low permeability rock containing gas trapped into occluded pores can be fragmented with the help of dynamic loads, and gas can be extracted in a much more efficient way compared with hydraulic fracturing, where only large macro cracks are formed with very few connections between occluded pores. At the stage of laboratory development of this technique, compressive underwater shock waves have been used to increase the intrinsic permeability of concrete specimens. In a previous study, pressure waves generated by pulsed arc electrohydraulic discharges in water were used in order to induce micro‐cracking and an increase of average permeability of concrete hollow cylinders subjected to confinement stresses (equivalent to geostatic stresses). We discuss here a 3‐D anisotropic constitutive model aimed at describing the dynamic response of these specimens. It is based on rate‐dependent continuum damage constitutive relations. Crack closure effects and damage‐induced anisotropy are included in the model. The directional growth of damage is related to the directional growth of material intrinsic permeability. Numerical simulations of damage induced by shock waves show good agreement with the experiments for various confinement levels of the specimens. Copyright © 2013 John Wiley & Sons, Ltd.
A tradeoff analysis of risk cutoffs for the quadruple serum screen for Down syndrome
Authors: Walker Brandon , Ashwood Edward R. , Jackson Brian R. , Lagrave Danielle 
Published: August 2013

ABSTRACTObjectivesIn maternal serum screening for Down syndrome, a cutoff of 1 : 270 is often used as a decision point to recommend invasive confirmatory testing. However, it has not been established how well this or any other cutoff relates to patient preferences, that is, the values that pregnant women attach to various screening outcomes. The purpose of this study was to examine the clinical and economic tradeoffs of a wide range of risk cutoffs for the quadruple screen.MethodsScreening costs and outcomes for multiple risk cutoffs were modeled using a Monte Carlo simulation.ResultsThe optimal cutoff for maternal serum screening depends on the relative values placed by the patient on different outcomes. Total societal costs were similar across the range of cutoffs.ConclusionsGiven that different screening outcomes are optimized by different cutoff values, a one‐size‐fits‐all approach may not be appropriate. © 2013 John Wiley & Sons, Ltd.
Are low maternal estriol levels a predictor for pro‐opiomelanocortin (POMC) deficiency caused by POMC mutation during pregnancy?
Authors: Aldemir Ozgur , Ozen Samim , Sanlialp Cigdem , Ceylaner Serdar 
Published: August 2013

ABSTRACTIsolated adrenocorticotropic hormone deficiency is a rare cause of adrenocortical insufficiency, especially in children, and may be an underestimated cause of neonatal death. Low estriol levels are usually correlated with compromised uteroplacental perfusion and associated with fetal death.A 30‐years old woman applied for pregnancy follow‐up. Ultrasonographic evaluation and karyotype of the fetus are normal. Low estriol level 0.34 MoM (% 0.24) was detected in maternal triple screening test. Amniocentesis was performed, and chromosomal disorders, steroid sulfatase deficiency, and Smith–Lemli–Opitz syndrome (SLOS) were excluded with karyotype, fluorescence in situ hybridization (FISH), and molecular analysis of SLOS, respectively. As their first child had pro‐opiomelanocortin (POMC) deficiency, POMC gene analysis was performed from both amniotic fluid and ethylene diamine tetra aceticacid (EDTA) blood sample of affected previous child, and homozygote mutation was detected. Fetus is diagnosed as POMC deficiency.We are presenting this case to discuss possible relationship of low maternal E3 levels and fetal POMC deficiency. © 2013 John Wiley & Sons, Ltd.
Phosphonated Polyethylenimine‐Coated Nanoparticles: Size‐ and Zeta‐Potential‐Adjustable Nanomaterials
Authors: Monteil Clément , Bar Nathalie , Moreau Bernard , Retoux Richard , Bee Agnès , Talbot Delphine , Villemin Didier 
Published: August 2013

Novel partially phosphonated polyethylenimine polymers are developed in order to control the modification of nanoparticle (NP) surfaces. This polymer is built by an accessible one‐step process. The numerous phosphonate functions assume both a strong covalent anchoring on metal oxide NPs and a modulation of electric charges, while amino groups are associated with dispersion preservation and subsequent biofunctionalization. The zwitterionic nanomaterials obtained display a good stability toward pH and ionic strength. According to the selected percentage of phosphonation and the polymer size, zeta potential, and diameter of the particles are controlled.
Brief Report: Rx1 Defines Retinal Precursor Identity by Repressing Alternative Fates Through the Activation of TLE2 and Hes4
Authors: Giannaccini Martina , Giudetti Guido , Biasci Daniele , Mariotti Sara , Martini Davide , Barsacchi Giuseppina , Andreazzoli Massimiliano 
Published: August 2013

Abstract
The molecular mechanisms underlying the acquisition of retinal precursor identity are scarcely defined. Although the homeobox gene Rx1 (also known as Rax) plays a major role in specifying retinal precursors and maintaining their multipotent state, the involved mechanisms remain to be largely deciphered. Here, following a highthroughput screen for genes regulated by Rx1, we found that this transcription factor specifies the fate of retinal progenitors by repressing genes normally activated in adjacent ectodermal territories. Unexpectedly, we also observed that Rx1, mainly through the activation of the transcriptional repressors TLE2 and Hes4, is necessary and sufficient to inhibit endomesodermal gene expression in retinal precursors of the eye field. In particular, Rx1 knockdown leads retinogenic blastomeres to adopt an endomesodermal fate, indicating a previously undescribed function for Rx1 in preventing the expression of endomesoderm determinants known to inhibit retinal fate. Altogether these data suggest that an essential requirement to establish a retinal precursor identity is the active inhibition of pathways leading to alternative fates. Stem Cells 2013;31:2842–2847
Genome-Wide Analysis of miRNA-mRNA Interactions in Marrow Stromal Cells
Authors: Balakrishnan Ilango , Yang Xiaodong , Brown Joseph , Ramakrishnan Aravind , Torok-Storb Beverly , Kabos Peter , Hesselberth Jay R. , Pillai Manoj M. 
Published: August 2013

Abstract
Regulation of hematopoietic stem cell proliferation, lineage commitment, and differentiation in adult vertebrates requires extrinsic signals provided by cells in the marrow microenvironment (ME) located within the bone marrow. Both secreted and cell-surface bound factors critical to this regulation have been identified, yet control of their expression by cells within the ME has not been addressed. Herein we hypothesize that microRNAs (miRNAs) contribute to their controlled expression. MiRNAs are small noncoding RNAs that bind to target mRNAs and downregulate gene expression by either initiating mRNA degradation or preventing peptide translation. Testing the role of miRNAs in downregulating gene expression has been difficult since conventional techniques used to define miRNA-mRNA interactions are indirect and have high false-positive and negative rates. In this report, a genome-wide biochemical technique (high-throughput sequencing of RNA isolated by cross-linking immunoprecipitation or HITS-CLIP) was used to generate unbiased genome-wide maps of miRNA-mRNA interactions in two critical cellular components of the marrow ME: marrow stromal cells and bone marrow endothelial cells. Analysis of these datasets identified miRNAs as direct regulators of JAG1, WNT5A, MMP2, and VEGFA; four factors that are important to ME function. Our results show the feasibility and utility of unbiased genome-wide biochemical techniques in dissecting the role of miRNAs in regulation of complex tissues such as the marrow ME. Stem Cells 2014;32:662–673
Mobile application for wildlife capture–mark–recapture data collection and query
Authors: Bateman Heather L. , Lindquist Timothy E. , Whitehouse Richard , Gonzalez Maria M. 
Published: August 2013

ABSTRACTCapture–mark–recapture (CMR) approaches are often used in the management and conservation of wildlife species and effective approaches to estimate populations rely on accurate data‐collection techniques. Unfortunately, sampling errors can arise at several steps in the CMR process. We designed and applied a mobile application (app) for field‐collected data from a CMR study on herpetofauna. Entering data into a digital format in the field using the mobile application eliminated timely steps to process handwritten data sheets and double‐checking data entries. Applications were developed for mobile devices on the iOS and Android operating systems. Both platforms have similar user interactions via data entry on a touch screen using pre‐programmed fields, checkboxes, drop‐down menus, and keypad entry. Our mobile application includes features to insure collection of all measurements in the field through pop‐up messages and can proof entries for valid formats. The application can assign unique numbers to newly captured individuals by querying the database for unused codes and eliminates the potential to assign 2 individuals with the same unique code. Technicians can query a database to view histories of previously captured animals from the field. During a 2‐month project, we estimated that using the mobile application instead of manual data entry and proofing via data sheets reduced our total project time by 10%. To our knowledge, this is the first application developed for mobile devices for biologists using CMR techniques and could be developed for use in other areas of field data collection. © 2013 The Wildlife Society.
Tuning Structural Topologies of Two Cadmium(II) Coordination Polymers via Isomeric Dipyridyl Ligands: Syntheses, Crystal Structures, and Luminescent Properties
Authors: Zhao Lu , Guo Feng 
Published: August 2013

AbstractAbstract. Two new coordination polymers {[Cd2(BDC)2(3‐bpmp)(H2O)2]·2H2O}n (1) and [Cd2(BDC)2(4‐bpmp)]n (2) [H2BDC = 5‐hydroxy‐isophthalic acid, 3‐bpmp = 1,4‐bis(3‐pyridylmethy)piperazine, and 4‐bpmp = 1,4‐bis(4‐pyridylmethy) piperazine] were synthesized via hydrothermal synthesis, and further characterized by IR spectroscopy, elemental analysis, XRD, and X‐ray crystallography. Complex 1 shows a two‐dimensional (4,4) sql topology and complex 2 features an 8‐connected hex topology. Moreover, the luminescent properties of complexes 1 and 2 were investigated in the solid state at room temperature.
Imaging Metal-on-Metal Hip Replacements: The Norwich Experience
Authors: Thomas Marianna S. , Wimhurst James A. , Nolan John F. , Toms Andoni P. 
Published: August 2013

Background Adverse reaction to metal debris is a relatively recently described and often a silent complication of metal-on-metal (MOM) total hip replacements (THR). The Norfolk & Norwich University Hospital has been performing metal artefact reduction (MARS) MRI for 8 years in a variety of different types of MOM THR. Questions/purposes The aims of this review are to describe the experience of using MARS MRI in Norwich and to compare our experience with that published by other groups. Methods A MEDLINE keyword search was performed for studies including MRI in MOM THR. Relevant publications were reviewed and compared with published data from the Norfolk & Norwich University Hospital. The similarities and differences between these data were compared and possible explanations for these discussed. Results MARS MRI appears to be the most useful tool for diagnosing, staging and monitoring adverse reactions to metal debris (ARMD). There appears to be no clinically useful association between clinical and serological markers of disease and the severity of MR findings. Although severe early ARMD is associated with significant morbidity, mild disease is often stable for years. If patients with normal initial MR examinations develop ARMD, this usually occurs 7 years. A 1-year interval between MRI examinations is reasonable in asymptomatic patients. Conclusions There is a general international consensus that ARMD is prevalent in symptomatic and asymptomatic patients with MOM THR and that while appearances vary with the type of prosthesis, there are characteristic features that make MARS MRI essential for diagnosis, staging and surveillance of the disease.
Dietary Fat in Relation to Erythrocyte Fatty Acid Composition in Men
Authors: Takkunen Markus , Ågren Jyrki , Kuusisto Johanna , Laakso Markku , Uusitupa Matti , Schwab Ursula 
Published: August 2013

AbstractErythrocyte membrane fatty acid (EMFA) composition is used in the validation of food frequency questionnaires (FFQ) and the evaluation of dietary fat quality. In this cross‐sectional study we aimed to investigate associations of diet with EMFA. Altogether, 1,033 randomly selected Finnish men, aged from 47 to 75 years filled in a FFQ and their EMFA composition was analyzed. Marine polyunsaturated fatty acid (PUFA) intake correlated positively with erythrocyte eicosapentaenoic and docosahexaenoic acids (rs = 0.415 and rs = 0.340, respectively, P < 0.001) and inversely with all n‐6 PUFA analyzed (P < 0.001). PUFA intake from spreads and cooking fats correlated positively with alpha‐linolenic (ALA), linoleic (LNA) and nervonic acids (rs = 0.229, rs = 0.160 and rs = 0.143, respectively, P < 0.001). Milk fat intake was associated with myristic and behenic acids (rs = 0.186 and rs = 0.132, respectively P < 0.001). Butter users had lower ALA and LNA proportions (mol%) than non‐users (0.16 ± 0.04 vs. 0.19 ± 0.05, P < 0.001 and 7.77 ± 1.02 vs. 8.12 ± 1.11, P = 0.001). Higher PUFA intake from meat was related to decreased long‐chain n‐3 (P < 0.001) and increased n‐6 PUFA (P < 0.001) proportions. In conclusion, EMFA composition reflects particularly well the intakes of n‐3 PUFA, whereas other associations remained lower. Yet, all main sources of dietary fat were related with EMFA. The dietary effect on the nervonic acid proportion was confirmed.
The Source of Fluid Deep to the Iliotibial Band: Documentation of a Potential Intra‐Articular Source
Authors: Jelsing Elena J. , Maida Eugene , Finnoff Jonathan T. , Smith Jay 
Published: August 2013

ObjectiveTo determine whether there is a consistent extension of the lateral synovial recess under the iliotibial band (ITB) in an unembalmed cadaveric model.DesignA prospective laboratory investigation.SettingA procedural skills laboratory of a tertiary medical center.SubjectsTwelve unembalmed cadaveric knee specimens.MethodsThe suprapatellar recess, ITB, and region deep to the ITB were examined sonographically to document the absence of fluid in each knee. Thereafter, 60 mL of normal saline solution was injected into each knee to distend the joint recesses. Postinjection sonographic examination of the ITB at the level of the lateral femoral epicondyle was repeated at 0°, 25°, and 45° of knee flexion to detect and characterize any fluid visualized in the region of the ITB. The location of fluid in relation to the ITB was recorded as anterior, deep, posterior, or a combination of these positions.ResultsFluid was observed anterior and deep to the ITB in 100% of 12 specimens. In 2 specimens, fluid also was noted posterior to the ITB. The presence and location of the fluid did not appear to change as a function of knee position. Using dynamic sonographic evaluation, we could track the fluid deep to the ITB back to the knee joint.ConclusionsThe lateral synovial recess appears to regularly extend beneath the anterior ITB. Fluid deep to the ITB should precipitate further evaluation of the knee joint when clinically indicated. Although distention of the lateral synovial recess is not always symptomatic, synovial irritation may be a pathoetiologic factor in the production of lateral knee pain syndromes, including ITB syndrome.