bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonfouling Response of Hydrophilic Uncharged Polymers
Authors: Serrano Ângela , Sterner Olof , Mieszkin Sophie , Zürcher Stefan , Tosatti Samuele , Callow Maureen E. , Callow James A. , Spencer Nicholas D. 
Published: June 2013

AbstractPolymeric ultrathin films present a possible line of attack against marine biofouling for some applications. A protocol that provides a reliable comparison of the resistance of different polymers to biofouling is described. This is achieved through the use of a common, azide‐terminated adhesion monolayer, to which different nonfouling polymers of various molecular weights, specifically poly(ethylene glycol) (PEG), poly(2‐ethyl‐2‐oxazoline) (PEOXA), poly(vinyl pyrrolidone) (PVP), poly(vinyl alcohol) (PVA), and dextran are covalently bound. These functionalized surfaces are characterized by dynamic contact angle, ellipsometry, and X‐ray photoelectron spectroscopy (XPS). To validate the developed protocol and evaluate performance against a selection of well‐known, marine‐fouling organisms, the nonfouling surfaces are subjected to a comparative biological study by exposure to a complex protein solution (with characterization via ellipsometry and quartz crystal microbalance with dissipation (QCM‐D)), marine bacteria (Cobetia marina and Marinobacter hydrocarbonoclasticus), and zoospores of the green alga Ulva linza. The resulting data are used to draw conclusions on structure‐property relationships. Chemical resistance towards marine fouling can be achieved using the described immobilization method, but is highly dependent on the species tested. Findings show that PVP (55 kDa)‐coated surfaces display consistent resistance towards all tested solutions and organisms and, hence, this polymer could be considered as a potential material for marine‐nonfouling applications.
Tough Composites Inspired by Mineralized Natural Materials: Computation, 3D printing, and Testing
Authors: Dimas Leon S. , Bratzel Graham H. , Eylon Ido , Buehler Markus J. 
Published: June 2013

AbstractComposites play an important role as structural materials in a range of engineering fields due to their potential to combine the best mechanical properties of their constituents. In biology, composites are ubiquitous and exhibit fascinating and precise architectures at fine length scales; bone, hexactinellid sponges and nacreous abalone shells are prime examples. Here, typical biological composite topologies are emulated with multi‐material 3D printing at micrometer resolution. From base materials that are brittle and exhibit catastrophic failure, synthetic composites are created with superior fracture mechanical properties exhibiting deformation and fracture mechanisms reminiscent of mineralized biological composites. This complementary computational model predictions of fracture mechanisms and trends in mechanical properties are in good agreement with the experimental findings. The reported findings confirm that specific topological arrangements of soft and stiff phases as a design mechanism enhances the mechanical behavior in composites. This study demonstrates 3D printing as a means to create fracture resistant composites. Moreover, these results indicate that one can use computer models to design composite materials to exhibit tailored fracture properties and then use 3D printing to synthesize materials with such mechanical performance.
Heat exposure in sugarcane harvesters in Costa Rica
Authors: Crowe Jennifer , Wesseling Catharina , Solano Bryan Román , Umaña Manfred Pinto , Ramírez Andrés Robles , Kjellstrom Tord , Morales David , Nilsson Maria 
Published: June 2013

AbstractBackgroundOccupational heat stress is a major concern in sugarcane production and has been hypothesized as a causal factor of a chronic kidney disease epidemic in Central America. This study described working conditions of sugarcane harvesters in Costa Rica and quantified their exposure to heat.MethodsNon‐participatory observation and Wet Bulb Globe Temperatures (WBGT) according to Spanish NTP (Technical Prevention Notes) guidelines were utilized to quantify the risk of heat stress. OSHA recommendations were used to identify corresponding exposure limit values.ResultsSugarcane harvesters carried out labor‐intensive work with a metabolic load of 261 W/m2 (6.8 kcal/min), corresponding to a limit value of 26° WBGT which was reached by 7:30 am on most days. After 9:15 am, OSHA recommendations would require that workers only work 25% of each hour to avoid health risks from heat.ConclusionsSugarcane harvesters are at risk for heat stress for the majority of the work shift. Immediate action is warranted to reduce such exposures. Am. J. Ind. Med. 56:1157–1164, 2013. © 2013 Wiley Periodicals, Inc.
TRIM5α polymorphism identification in cynomolgus macaques of Vietnamese origin and Chinese rhesus macaques
Authors: Zhang Guiqing , Qiu Wei , Xiang Ruirui , Ling Fei , Zhuo Min , Du Hongli , Wang Jufang , Wang Xiaoning 
Published: June 2013

AbstractTRIM5α is a retroviral restriction factor, in which the B30.2 (SPRY) and coiled‐coil domains cooperate to determine the specificity of TRIM5α‐mediated capture of retroviral capsids. Here, all exons of TRIM5α were analyzed in 39 Vietnamese cynomolgus macaques (VCE) and 29 Chinese rhesus macaques (CR). Our results revealed the presence of 22 alleles using the PHASE 2.0 software package (PHylogenetics And Sequence Evolution), including two novel species‐specific alleles with a low frequency in VCE in exons 4 and 8, which encoded the coiled‐coil and B30.2 (SPRY) domains, respectively. Nine alleles were detected in both VCE and CR, while four alleles were likely shared between the species. Of these alleles, the highest frequencies of 38% and 26% occurred in VCE and CR, respectively. Importantly, we found that some alleles encoded the same coiled‐coil domain, but not the SPRY domain. In contrast, other alleles encoded the same SPRY domain, but not the coiled‐coil domain. Our findings will contribute to the understanding of the interaction between the two domains and the determination of the specificity of TRIM5α‐mediated capture of retroviral capsids. Our results from the phylogenetic trees constructed for VCE and CR suggested that the macaques' ability to inhibit SIV replication became gradually stronger if they carried corresponding alleles in four clades (clades4–7). More interesting, in clade3, both novel allele pairs (4E100a, 10E147a) and allele pairs (7R17b and 13R11b), which had the strong ability to inhibit SIV replication, originated from the same ancestral allele, suggesting that the novel alleles might play a key role to determine an animal's ability to inhibit SIV/HIV replication. However, further studies are needed to increase our understanding of the genetic background of TRIM5α in these two macaque species. Am. J. Primatol. 75:938–946, 2013. © 2013 Wiley Periodicals, Inc.
Budesonide nasal irrigations in the postoperative management of chronic rhinosinusitis
Authors: Jang David W. , Lachanas Vasileios A. , Segel Jamie , Kountakis Stilianos E. 
Published: June 2013

BackgroundNasal steroids play an important role in the postoperative management of patients with chronic rhinosinusitis (CRS). However, commercially available nasal steroid sprays may not deliver adequate amounts of medication to the entire postoperative sinus cavity. The off‐label use of budesonide nasal irrigation (BNI) theoretically solves this problem by delivering concentrated steroid solution through a high‐pressure, high‐volume system. Several studies have attested to the safety of BNI, but there are very few reports of its efficacy.MethodsThis is a retrospective review of prospectively‐collected data. We identified 60 patients who were prescribed BNI postoperatively, but had a lapse in therapy for 1 month or longer. The 20‐item Sinonasal Outcomes Test (SNOT‐20) and Lund‐Kennedy endoscopy scores while the patients were using BNI were compared with scores from the same patients while they were not using BNI. Student paired t test was used for statistical analysis.ResultsThirty patients had eosinophilic chronic rhinosinusitis (eCRS) with polyps (eCRSwNP), 13 had allergic fungal sinusitis (AFS), 13 had Samter's triad (ST), and 4 had eosinophilic chronic rhinosinusitis without polyps (eCRSsNP). Mean follow‐up time was 25 months (range, 2–89 months). Overall, SNOT‐20 scores were significantly lower with BNI (p < 0.05). On subgroup analysis, SNOT‐20 scores were significantly improved with BNI for patients with eCRS and Samter's triad (p = 0.04, 0.03). Endoscopy scores were significantly improved only in the eCRS group (p = 0.02).ConclusionThe addition of BNI is beneficial in the postoperative management of patients with CRS.
Long‐term risk of recurrent vascular events after young stroke: The FUTURE study
Authors: Rutten‐Jacobs Loes C. A. , Maaijwee Noortje A. M. , Arntz Renate M. , Schoonderwaldt Henny C. , Dorresteijn Lucille D. , van der Vlugt Maureen J. , van Dijk Ewoud J. , de Leeuw Frank‐Erik 
Published: June 2013

ObjectiveLong‐term data on recurrent vascular events after young stroke are limited. Our objective was to examine the long‐term risk of recurrent vascular events after young stroke.MethodsWe prospectively included 724 consecutive patients with a first‐ever transient ischemic attack (TIA), ischemic stroke, or intracerebral hemorrhage (ICH), aged 18 to 50 years, admitted to our hospital between January 1, 1980 and November 1, 2010. Outcomes were (1) stroke; (2) myocardial infarction or cardiac or peripheral arterial revascularization procedures; or (3) composite event of these, whichever occurred first.ResultsAfter a mean follow‐up of 9.1 years (standard deviation = 8.2, range = 0–31.0), 142 patients (19.6%) had at least 1 recurrent vascular event. Cumulative 20‐year risk of stroke was 17.3% (95% confidence interval [CI] = 9.5–25.1) after TIA, 19.4% (95% [CI] = 14.6–24.3) after ischemic stroke, and 9.8% (95% CI = 1.0–18.7) after ICH. Cumulative 20‐year risk of any vascular event was 27.7% (95% CI = 18.5–37.0) after TIA and 32.8% (95% CI = 26.7–38.9) after ischemic stroke. Age and male sex were associated with other arterial events, but not with stroke. Among TOAST (Trial of Org 10172 in Acute Stroke Treatment) subtypes, adjusted for age, sex, and decennium of inclusion, atherothrombotic stroke, cardioembolic stroke, and lacunar stroke were associated with recurrent stroke (hazard ratio [HR] = 2.72, 95% CI = 1.34–5.52; HR = 2.49, 95% CI = 1.23–5.07; and HR = 2.92, 95% CI = 1.45–5.88, respectively).InterpretationPatients with young stroke remain at substantial risk of recurrent vascular events for decades, suggesting that the underlying disease that caused stroke at a young age continues to put these patients at a high risk for vascular disease throughout their lives. Ann Neurol 2013;74:592–601
Accurate measurements of the Avogadro and Planck constants by counting silicon atoms
Authors: Bettin Horst , Fujii Kenichi , Man John , Mana Giovanni , Massa Enrico , Picard Alain 
Published: June 2013

AbstractFundamental constants link seemingly different fields of physics and seemingly different quantities and measurement units. Consequently, they are of the utmost interest in metrology and it has been planned to redefine the kilogram by fixing the numerical value of the Planck constant. This paper summarises the methods to measure the ratio between the Planck constant and a mass and reviews the determination of the Avogadro constant by counting the atoms in a silicon crystal highly enriched by the 28Si isotope.
The Winding Pathway to Erythropoietin Along the Chemistry–Biology Frontier: A Success At Last
Authors: Wilson Rebecca M. , Dong Suwei , Wang Ping , Danishefsky Samuel J. 
Published: June 2013

AbstractThe total synthesis of a homogeneous erythropoietin (EPO), possessing the native amino acid sequence and chitobiose glycans at each of the three wild‐type sites of N glycosylation, has been accomplished in our laboratory. We provide herein an account of our decade‐long research effort en route to this formidable target compound. The optimization of the synergy of the two bedrock sciences we now call biology and chemistry was central to the success of the synthesis of EPO.
Preparation and characterization of polyaniline–1‐hydroxyethane 1,1‐diphosphonic acid salt and its application as a catalyst for the synthesis of N‐benzylidine‐2‐phenyl imidazo[1,2‐a]pyridines
Authors: Palaniappan Srinivasan , Rajender Boddula , Ravi Bolagam 
Published: June 2013

ABSTRACTA novel, efficient, and easily synthesizable catalyst, an emeraldine form of polyaniline (PANI)−1‐hydroxyethane 1,1‐diphosphonic acid salt (HEDP), was successfully synthesized and demonstrated as a reusable polymer‐based solid acid catalyst in the synthesis of N‐benzylidine‐2‐phenyl imidazo[1,2‐a]pyridines with 2‐aminopyridine with aromatic aldehydes and trimethyl silylcyanide at room temperature. PANI–HEDP was characterized by Fourier transform infrared spectroscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, field emission scanning electron microscopy, and conductivity measurements. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2995–3000, 2013
Preparation and characterization of electrospun PLA/nanocrystalline cellulose‐based composites
Authors: Pirani Sanaa , Abushammala Hatem M. N. , Hashaikeh Raed 
Published: June 2013

ABSTRACTBiodegradable nanocomposites of Nanocrystalline Cellulose (NCC) and electrospun poly‐(lactic acid) were prepared via a new mixing technique. Dispersion of hydrophilic NCC in hydrophobic PLA was improved through aqueous mixing and freeze drying of perfectly suspended NCC with PLA nanofibers. Freeze drying produced aerogels with good mechanical integrity. The aerogels were further processed via hot pressing. Resulting composites displayed an improvement in mechanical properties, which was greatest at temperatures below the glass transition temperature of PLA. The optimum compositions were found to be in the 0.5–3% NCC (by weight) range. Experiments performed also showed that due to electrospinning, the crystallinity of the PLA slightly increased and this is accompanied by a decrease in its glass transition temperature. Furthermore, adding NCC to the electrospun PLA matrix did not alter the crystallinity of the final composite. The composites investigated proved their potential to be used in packaging and tissue engineering applications. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3345–3354, 2013
Cell imaging and DNA delivery in fibroblastic cells by conjugated polyelectrolytes
Authors: Shin Yong Cheol , Lee Jong Ho , Jeong Ji‐Eun , Kim Boram , Lee Eun Ji , Jin Oh Seong , Jung Tae Gon , Lee Jun Jae , Woo Han Young , Han Dong‐Wook 
Published: June 2013

AbstractThis study concentrates on the potential application of conjugated polyelectrolytes (CPEs) to cell imaging and DNA delivery. Four different types of polyfluorene copolymers, namely, PAHFP‐Br, PAEFP‐Br, PAHFbT‐Br, and PSBFP‐Na, which have the same π‐conjugated backbone but different side chains, were synthesized. For cytotoxicity testing, L‐929 fibroblastic cells were treated with increasing concentrations (0–50 µM) of each CPE and then cell viability was determined by WST‐8 assay. Cellular uptake of CPEs into cultured L‐929 cells was observed by fluorescence microscopy. To examine DNA delivery by CPEs, the cells were incubated for 1 H with PAHFP‐Br/fluorescein (Fl)‐labeled single‐stranded DNA (ssDNA‐Fl) complex and then visualized by fluorescence microscopy. Cytotoxicity of CPEs was increased in a dose‐dependent manner but at lower than 10 µM, PAHFP‐Br, PAEFP‐Br, and PSBFP‐Na did not show any cytotoxic effects on the cells. When added to cell cultures at 1 µM, PAHFP‐Br/ssDNA‐Fl complex was delivered and then dissociated into PAHFP‐Br and ssDNA‐Fl within the cells. This result implies that PAHFP‐Br can enable cell imaging and DNA delivery into fibroblastic cells. Therefore, it is suggested that PAHFP‐Br with various advantages such as low cytotoxicity and high fluorescence efficiency can be extensively used as a potential agent for cell imaging and gene delivery.
Unusual Folding Propensity of an Unsubstituted β,γ‐Hybrid Model Peptide: Importance of the CH⋅⋅⋅O Intramolecular Hydrogen Bond
Authors: Venugopalan Paloth , Kishore Raghuvansh 
Published: June 2013

AbstractThe single‐crystal X‐ray diffraction analysis of a β,γ‐hybrid model peptide Boc‐β‐Ala‐γ‐Abu‐NH2 revealed the existence of four crystallographically independent molecules (A, B, C and D conformers) in the asymmetric unit. The analysis revealed that unusual β‐turn‐like folded structures predominate, wherein the conformational space of non‐proteinogenic β‐Ala and γ‐Abu residues are restricted to gauche‐gauche‐skew and skew‐gauche‐trans‐skew orientations, respectively. Interestingly, the U‐shaped conformers are seemingly stabilised by an effective unconventional CH⋅⋅⋅O intramolecular hydrogen bond, encompassing a non‐covalent 14‐membered ring‐motif. Taking into account the signs of torsion angles, these conformers could be grouped into two distinct categories, A/B and C/D, establishing the incidence of non‐superimposable stereogeometrical features across a non‐chiral one‐component peptide model system, that is, “mirror‐image‐like” relationships. The natural occurrence of β‐Ala and γ‐Abu entities in various pharmacologically important molecules, coupled with their biocompatibilities, highlight how the non‐functionalised β,γ‐hybrid segment may offer unique advantages for introducing and/or manipulating a wide spectrum of biologically relevant hydrogen bonded secondary structural mimics in short synthetic peptides.
A Dioxane Template for Highly Selective Epoxy Alcohol Cyclizations
Authors: Mousseau James J. , Morten Christopher J. , Jamison Timothy F. 
Published: June 2013

AbstractLadder polyether natural products are a class of natural products denoted by their high functional‐group density and large number of well‐defined stereocenters. They comprise the toxic component of harmful algal blooms (HABs), having significant negative economic and environmental ramifications. However, their mode of action, namely blocking various cellular ion channels, also denotes their promise as potential anticancer agents. Understanding their potential mode of biosynthesis will not only help with developing ways to limit the damage of HABs, but would also facilitate the synthesis of a range of analogs with interesting biological activity. 1,3‐Dioxan‐5‐ol substrates display remarkable ‘enhanced template effects’ in water‐promoted epoxide cyclization processes en route to the synthesis of these ladder polyether natural products. In many cases, they provide near complete endo‐to‐exo selectivity in the cyclization of epoxy alcohols, thereby strongly favoring the formation of tetrahydropyran (THP) over tetrahydrofuran (THF) rings. The effects of various Brønsted and Lewis acidic and basic conditions are explored to demonstrate the superior selectivity of the template over the previously reported THP‐based epoxy alcohols. In addition, the consideration of other synthetic routes are also considered with the goal of gaining rapid access to a plethora of potential starting materials applicable towards the synthesis of ladder polyethers. Finally, cascade sequences with polyepoxides are investigated, further demonstrating the versatility of this new reaction template.
Metal Amides as the Simplest Acid/Base Catalysts for Stereoselective Carbon–Carbon Bond‐Forming Reactions
Authors: Yamashita Yasuhiro , Kobayashi Shū 
Published: June 2013

AbstractIn this paper, new possibilities for metal amides are described. Although typical metal amides are recognized as strong stoichiometric bases for deprotonation of inert or less acidic hydrogen atoms, transition‐metal amides, namely silver and copper amides, show interesting abilities as one of the simplest acid/base catalysts in stereoselective carbon–carbon bond‐forming reactions.
Improved Photovoltaic Performance of MEH‐PPV/PCBM Solar Cells via Incorporation of Si Nanocrystals
Authors: Yan Quanxiang , Zuo Lijian , Gu Zhuowei , Yang Ligong , Wang Rong , Wang Mang , Chen Hongzheng 
Published: June 2013

AbstractWe have studied the effect of silicon nanocrystals (SiNCs) as a third component on performance of organic bulk heterojunction solar cells composed of poly[2‐methoxy,5‐(2′‐ethylhexyloxy)‐1,4‐phenylene vinylene] (MEH‐PPV):[6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) blend film. By adding suitable amounts of SiNCs into MEH‐PPV:PCBM blend, the device performance such as external quantum efficiency, short circuit current density (JSC), and power conversion efficiency (PCE) improved. Incorporation of 2.5% SiNCs in the blend led to 13.6% improvement of JSC, which in turn resulted in 18% improvement of PCE up to 2.28%. The improved performance was mainly due to the improvements both in the charge generation from the interface of MEH‐PPV/SiNCs and the charge collection at the cathode.
Solvent‐free Synthesis of Hexagonal Iron Sulfide Nanoflowers
Authors: Wang Xia , Zhou Wenhui , Chang Zhixian , Zhou Zhengji , Wu Sixin 
Published: June 2013

AbstractEmploying green and economic solvent‐free synthesis route, hexagonal iron sulfide (Fe7S8) nanoflowers were successfully synthesized for the first time. In the experiment, ferric hexadecylxanthate was used as the precursor, and hexagonal iron sulfide (Fe7S8) nanoflowers were obtained by thermal decomposition of the precursor at 260°C without any additional solvent or inert gas protection. The as‐prepared iron sulfide nanoflowers were characterized by means of X‐ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The characterization results indicated that the nanoflowers had uniform size distribution with an average size of about 160 nm. The proposed strategy provides a possible general route for the synthesis of other metal chalcogenide nanostructures.
Cytarabine, Ki‐67, and SOX11 in patients with mantle cell lymphoma receiving rituximab‐containing autologous stem cell transplantation during first remission
Authors: Chakhachiro Zaher I. , Saliba Rima M. , Okoroji Grace‐Julia , Korbling Martin , Alousi Amin M. , Betul Oran , Anderlini Paolo , Ciurea Stefan O. , Popat Uday , Champlin Richard , Samuels Barry I. , Medeiros L. Jeffrey , Bueso‐Ramos Carlos , Khouri Issa F. 
Published: June 2013

BACKGROUNDIn the current study, the authors report the results of 39 patients with mantle cell lymphoma (MCL) who were treated with chemotherapy and high‐dose rituximab‐containing autologous stem cell transplantation (ASCT) during their first disease remission.METHODSThe median age of the patients was 54 years. At the time of diagnosis, 87% of patients had Ann Arbor stage IV disease, and 77% had bone marrow involvement. A Ki‐67 level of > 30% was found in 11 of 27 patients (40%), and SOX11 (SRY [sex determining region Y)‐box 11] expression was found to be positive in 17 of 18 patients (94%). Twenty‐seven patients (69%) underwent induction therapy with high‐dose cytarabine‐containing chemotherapy. Rituximab was administered during stem cell collection at a dose of 1000 mg/m2 on days +1 and +8 after ASCT.RESULTSThe estimated 4‐year overall survival and progression‐free survival rates were 82% and 59%, respectively. Twelve patients experienced disease recurrence. Fifteen of 16 patients who were alive and in complete remission at 36 months remained so at a median follow‐up of 69 months (range, 38 months‐145 months). The only determinant of recurrence risk found was a Ki‐67 level of > 30%. Seven of 11 patients with a Ki‐67 level > 30% experienced disease recurrence within the first 3 years versus only 3 of 16 patients with a Ki‐67 level ≤ 30% (P = .02). Patients who received high‐dose cytarabine did not have a significantly different risk of developing disease recurrence compared with other patients (P = .7).CONCLUSIONSAdministering ASCT with rituximab during stem cell collection and immediately after transplantation may induce a continuous long‐term disease remission in patients with MCL with a Ki‐67 level of ≤ 30%. Cancer 2013;119:3318–25. © 2013 American Cancer Society.