bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of hybrid hollow microspheres on thermal insulation performance and mechanical properties of silicone rubber composites
Authors: Zhao Xiong‐Wei , Zang Chong‐Guang , Sun Ya‐Lun , Zhang Yu‐Long , Wen Yu-Quan , Jiao Qing‐Jie 
Published: November 2017

ABSTRACTHollow microspheres (HM) of ceramic, silica, and glass‐filled silicone rubber (SR) composites were prepared, and the effects of hybrid HM on thermal and mechanical properties of composites were investigated. The results indicate that hybrid HM can effectively improve the thermal insulation property of HM/SR composites. Especially, for sample 15S, the thermal conductivity and thermal degradation temperature reached 0.1273 W/m K and 521 °C (45 °C higher than that of neat SR), respectively. Besides, thermal insulation performance was improved, showing as a temperature of 103.2 °C after 15 min heating, which is 37.8 °C lower than that of SR. The tensile strength of composites was enhanced from 1.92 MPa at 11.56 vol % hollow silica microspheres (HSM) loading to 3.08 MPa at 21.88 vol % HSM loading. Moreover, the compressive strength was improved from 3.33 to 5.68 MPa by introducing more hollow ceramic microspheres into the matrix, in this case, from 7.79 to 15.33 vol %. Furthermore, the failure mechanism was analyzed. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46025.
Design and fabrication of flexible poly(vinyl chloride) dielectric composite reinforced with ZnO microvaristors
Authors: Mathews Jeen Maria , Santhosh Balanand , Abdul Azeez Peer Mohamed , Solaiappan Ananthakumar 
Published: November 2017

ABSTRACTFlexible poly(vinyl chloride)/varistor composites were fabricated by solution casting method. High‐field ZnO varistor particles processed from micron‐sized Zn dust is explored as multifunctional filler for PVC composites. Mechanical blending of Zn dust with La2O3‐CeO2 rare earths and varistor forming minor additives followed by sintering at 1250 °C resulted in fine‐grained ZnO varistors. Bulk varistor was subsequently milled to obtain ZnO microvaristor grains. The effect of microvaristor on the UV stability, dielectric, and mechanical properties of the PVC composite was analyzed. The varistor filler in PVC enhanced the microhardness and retained the tensile properties without any significant loss. After UV irradiation PVC/varistor composite shows remarkable mechanical stability retention (95%) compared to pure PVC (75%). Also, microvaristor reinforcement resulted in dielectric constant tunability (ɛ = 2–37) without any drastic change in the dielectric loss (0.02–0.05). Thus, Zn dust‐derived ZnO varistors could be potentially exploited to design functional PVC composites for electronic applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46031.
The status and distribution of a newly identified endemic galaxiid in the eastern Cape Fold Ecoregion, of South Africa
Authors: Chakona Gamuchirai , Swartz Ernst R. , Chakona Albert 
Published: November 2017

Abstract

DNA‐based studies have uncovered cryptic species and lineages within almost all freshwater fishes studied thus far from the Cape Fold Ecoregion (CFE) of South Africa. These studies have changed the way the CFE is viewed, as almost all stream fishes that were previously considered to be of low conservation priority, because they were perceived to have broad geographical ranges, contain multiple historically isolated lineages, many of which are narrow‐range endemics.
As stream fishes of the CFE are of conservation concern owing to threats mainly posed by habitat degradation, invasion by alien species and hydrological modification, re‐evaluation of the distribution and conservation status of newly identified unique lineages is required to inform the development and implementation of effective conservation and management strategies.
The present study conducted an IUCN Red List conservation assessment of a newly identified lineage of the Galaxias zebratus species complex (hereafter referred to as Galaxias sp. ‘Joubertina’) to identify key threats and provide recommendations to conservation authorities on appropriate measures to reduce extinction risk.
The lineage met the qualifying threshold for the Endangered category because of its very restricted geographic range, few remaining secure populations, small known population sizes and the intensity of threats to most of the populations. Only six populations remain, one of which could be an ‘extralimital’ population potentially established through an inter‐basin water transfer scheme.
Galaxias sp. ‘Joubertina’ is threatened by invasive piscivores, habitat degradation and excessive water abstraction. These impacts have fragmented remnant populations, raising concerns about potential long‐term adverse impacts on genetic diversity and evolutionary potential of this lineage.
Immediate conservation measures should protect remnant populations from further impacts, while long‐term measures should aim to restore historical connectivity to reduce the potential deleterious effects of inbreeding in the small isolated populations.
Structure‐activity studies of peptidomimetics based on kinase‐inhibitory region of suppressors of cytokine signaling 1
Authors: La Manna Sara , Lopez‐Sanz Laura , Leone Marilisa , Brandi Paola , Scognamiglio Pasqualina Liana , Morelli Giancarlo , Novellino Ettore , Gomez‐Guerrero Carmen , Marasco Daniela 
Published: November 2017

AbstractSuppressors of Cytokine Signaling (SOCS) proteins are negative regulators of JAK proteins that are receptor‐associated tyrosine kinases, which play key roles in the phosphorylation and subsequent activation of several transcription factors named STATs. Unlike the other SOCS proteins, SOCS1 and 3 show, in the N‐terminal portion, a small kinase inhibitory region (KIR) involved in the inhibition of JAK kinases. Drug discovery processes of compounds based on KIR sequence demonstrated promising in functional in vitro and in inflammatory animal models and we recently developed a peptidomimetic called PS5, as lead compound. Here, we investigated the cellular ability of PS5 to mimic SOCS1 biological functions in vascular smooth muscle cells and simultaneously we set up a new binding assay for the screening and identification of JAK2 binders based on a SPR experiment that revealed more robust with respect to previous ELISAs. On this basis, we designed several peptidomimetics bearing new structural constraints that were analyzed in both affinities toward JAK2 and conformational features through Circular Dichroism and NMR spectroscopies. Introduced chemical modifications provided an enhancement of serum stabilities of new sequences that could aid the design of future mimetic molecules of SOCS1 as novel anti‐inflammatory compounds.
The burst‐phase folding intermediate of ribonuclease H changes conformation over evolutionary history
Authors: Lim Shion A. , Marqusee Susan 
Published: November 2017

AbstractThe amino acid sequence encodes the energy landscape of a protein. Therefore, we expect evolutionary mutations to change features of the protein energy landscape, including the conformations adopted by a polypeptide as it folds to its native state. Ribonucleases H (RNase H) from Escherichia coli and Thermus thermophilus both fold via a partially folded intermediate in which the core region of the protein (helices A‐D and strands 4‐5) is structured. Strand 1, however, uniquely contributes to the T. thermophilus RNase H folding intermediate (Icore+1), but not the E. coli RNase H intermediate (Icore) (Rosen & Marqusee, PLoS One 2015). We explore the origin of this difference by characterizing the folding intermediate of seven ancestral RNases H spanning the evolutionary history of these two homologs. Using fragment models with or without strand 1 and FRET probes to characterize the folding intermediate of each ancestor, we find a distinct evolutionary trend across the family—the involvement of strand 1 in the folding intermediate is an ancestral feature that is maintained in the thermophilic lineage and is gradually lost in the mesophilic lineage. Evolutionary sequence changes indeed modulate the conformations present on the folding landscape and altered the folding trajectory of RNase H.
Influence of national centralization of oesophagogastric cancer on management and clinical outcome from emergency upper gastrointestinal conditions
Authors: Markar S R , Mackenzie H , Wiggins T , Askari A , Karthikesalingam A , Faiz O , Griffin S M , Birkmeyer J D , Hanna G B 
Published: November 2017

Abstract

Background
In England in 2001 oesophagogastric cancer surgery was centralized. The aim of this study was to evaluate whether centralization of oesophagogastric cancer to high-volume centres has had an effect on mortality from different emergency upper gastrointestinal conditions.

Methods
The Hospital Episode Statistics database was used to identify patients admitted to hospitals in England (1997–2012). The influence of oesophagogastric high-volume cancer centre status (20 or more resections per year) on 30- and 90-day mortality from oesophageal perforation, paraoesophageal hernia and perforated peptic ulcer was analysed.

Results
Over the study interval, 3707, 12 441 and 56 822 patients with oesophageal perforation, paraoesophageal hernia and perforated peptic ulcer respectively were included. There was a passive centralization to high-volume cancer centres for oesophageal perforation (26·9 per cent increase), paraoesophageal hernia (19·5 per cent increase) and perforated peptic ulcer (23·0 per cent increase). Management of oesophageal perforation in high-volume centres was associated with a reduction in 30-day (HR 0·58, 95 per cent c.i. 0·45 to 0·74) and 90-day (HR 0·62, 0·49 to 0·77) mortality. High-volume cancer centre status did not affect mortality from paraoesophageal hernia or perforated peptic ulcer. Annual emergency admission volume thresholds at which mortality improved were observed for oesophageal perforation (5 patients) and paraoesophageal hernia (11). Following centralization, the proportion of patients managed in high-volume cancer centres that reached this volume threshold was 88·0 per cent for oesophageal perforation, but only 30·3 per cent for paraoesophageal hernia.

Conclusion
Centralization of low incidence conditions such as oesophageal perforation to high-volume cancer centres provides a greater level of expertise and ultimately reduces mortality.
Development and validation of a high‐performance liquid chromatography method for determination of lisinopril in human plasma by magnetic solid‐phase extraction and pre‐column derivatization
Authors: Rastkari Noushin , Ahmadkhaniha Reza 
Published: November 2017

AbstractA sensitive, reliable and simple HPLC method was developed for the determination of lisinopril in human plasma. The method consists of extraction and clean‐up steps based on magnetic solid‐phase extraction and pre‐column derivatization with a fluorescent reagent. The mobile phase consisted of a mixture of methanol–sodium dihydrogen phosphate (pH 3.0; 0.005 m; 75:25, v/v). The flow rate was set at 0.7 mL/min. Fluorescence detection was performed at 470nm excitation and 530nm emission wavelengths. Total chromatography run time was 5 min. The average extraction recovery of lisinopril and fluvoxamine (internal standard) was ≥82.8%. The limits of detection and quantification were determined as 1 and 3 ng/mL respectively. The method exhibited a linear calibration line over the concentration range of 3–1000 ng/mL with coefficient of determination (r2) of ≥0.98. The within‐run and between‐run precisions were satisfactory with values of CV of 1.8–12.8% (accuracy from 99.2 to 94.7%) and 2.4–13.7% (accuracy from 99.5 to 92.2%), respectively. These developments led to considerable improvement in method sensitivity and reliability. The method was validated according to the US Food and Drug Administration guidelines. Therefore, it can be considered as a suitable method for determination of lisinopril in plasma samples.
Comparative pharmacokinetics study of orientin in rat plasma by UHPLC‐MS/MS after intravenous administration of single orientin and Trollius chinensis Bunge extract
Authors: Zhao Nan , Sun Qi , Song Yang , Wang Lin , Zhang Tingjian , Meng Fanhao 
Published: November 2017

AbstractOrientin showed a broad array of biological activities, and it is the major bioactive compound in the Trollius chinensis Bunge. The aim of this study was to investigate the comparative pharmacokinetics of orientin after intravenous administration of single orientin and T. chinensis Bunge extract. Sample preparation involved a simple one‐step deproteinization procedure with acetonitrile. Chromatographic separation was achieved on a Waters BEH C18 column with a mobile phase consisting of acetonitrile and water containing 0.1% formic acid in an isocratic elution way. The detection was accomplished in multiple reaction monitoring mode with positive electrospray ionization. The pharmacokinetic properties of orientin were compared after intravenous administrations of pure orientin and T. chinensis Bunge extract to rats with approximately the same dosage of 10 mg/kg. The results of the study indicate that the pharmacokinetics of orientin in rat plasma show significant differences between two groups. This is useful for the clinical uses of therapeutic dosing of orientin and T. chinensis Bunge.
Does the severity of left ventricular systolic dysfunction impact outcomes of Mitraclip therapy: How low is too low?
Authors: Cilingiroglu Mehmet , Hakeem Abdul 
Published: November 2017

Key Points

Percutaneous mitral valve repair for symptomatic severe mitral regurgitation has rapidly evolved as a viable therapeutic option for high‐surgical risk patients.
Both randomized clinical studies as well as real world registry data have demonstrated significant improvement in severity of MR and clinical outcomes.
In carefully selected patients with severely reduced left ventricular systolic function and severe symptomatic MR, Mitraclip therapy seems to show promise.
Thoracic endovascular repair versus medical management for acute uncomplicated type B aortic dissection
Authors: Enezate Tariq H. , Omran Jad , Al‐Dadah Ashraf S. , White Christopher , Patel Mitul , Mahmud Ehtisham , Fattori Rossella , Goldstein Jeffrey A. , Goswami Nilesh , Gray William A. , Bhatt Deepak L. 
Published: November 2017

AbstractBackgroundCurrent treatment options and outcomes for acute uncomplicated thoracic Type‐B aortic dissection (TBAD) remain unclear between medical management (MED) and thoracic endovascular aortic repair (TEVAR). In this study we aim to compare both strategies in terms of all‐cause mortality, aortic dilation, and aortic rupture.MethodsMEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were queried from January 1990 through March 2017. Only studies comparing TEVAR to MED for acute uncomplicated TBAD were included. Random‐effects meta‐analysis was used to pool outcomes across studies. Study outcomes included short (1 month), intermediate (1 year), and mid‐term (2–5 year) all‐cause mortality. Additional outcomes included aortic dilation and rupture at 1 year.ResultsA total of 1,960 patients (64.3 years; 75.8% male) were included from six studies (one prospective and five retrospective). No difference was observed in short‐term (odd ratio [OR] 0.73 with 95% confidence interval [CI] 0.47 to 1.12, P = 0.15), intermediate (OR 0.99 with 95% CI 0.56 to 1.73, P = 0.96), or mid‐term all‐cause mortality (OR 1.12 with 95% CI 0.54 to 2.32, P = 0.75). No difference in aortic dilation with either modality was noted at 1‐year (OR 1.11 with 95% CI 0.76 to 1.64, P = 0.59). TEVAR was associated with a significantly lower 1‐year risk of aortic rupture (OR 2.49 with 95% CI 1.23 to 5.06, P = 0.01).ConclusionThere were no short, intermediate, or mid‐term differences in mortality between TEVAR or MED in patients with acute uncomplicated TBAD. Although the dilation rate was similar between both groups, TEVAR was associated with lower likelihood of aortic rupture at 1 year.
Diagnostics of sintering processes on the basis of PCA and two‐level neural network model
Authors: Egorova E.G. , Rudakova I.V. , Rusinov L.A. , Vorobjev N.V. 
Published: November 2017

AbstractThe application of chemometrics methods to continuous monitoring and diagnostics of sintering process faults for improving iron‐ore sinter quality is considered in the article. The sintering process is among complex multivariate processes.A number of agglomeration process faults have often similar symptoms, resulting in late fault detection by an operator and as a consequence, wrong process control decisions. To support the efficient operative decision making, it is proposed to use the process fault monitoring and diagnostics system.The proposed system uses a two‐level neural network (NN) diagnostic model. The high‐level neural network is used to localize the process faults whereas their reasons are determined by the low‐level neural networks. To reduce essentially the time of HL‐NN training and retraining, the task dimension is preliminarily reduced with the principal component analysis method so that the scores obtained from initial data are fed into high‐level neural network inputs. The use of principal component analysis allowed detection of sintering process faults with T2 and Q statistics. Only upon detecting the fault, a NN diagnostic model starts working to determine the fault reason. The system algorithm provides for special measures to prevent the NN from possible “loss” of the identified fault due to operator's inactivity.To increase the diagnosis depth for controlling fault symptoms that are evident on the sinter cake surface, optical digital cameras are installed and images from them are processed with proposed algorithms on the basis of fuzzy clusterization to take into account uncertainties in the initial information.
Ce3+‐Sensitized Tm3+/Mn2+‐Doped NaYF4 Colloidal Nanocrystals: Intense Cool White Light from a Phosphor‐Coated UV LED
Authors: Adusumalli Venkata N. K. B. , Koppisetti Heramba V. S. R. M. , Mahalingam Venkataramanan 
Published: November 2017

AbstractColloidal NaYF4:Ce3+/Tm3+/Mn2+ nanocrystals found to be an efficient single component phosphor to produce intense white light. The use of Mn2+ ions instead of green‐ and red‐emitting Ln3+ ions is interesting as the later are expensive and less abundant. The single band blue emission of Tm3+ ions was combined with the broadband green–yellow emission of Mn2+ ions to produce strong white light emission using Ce3+ ions as excitation source. Interestingly, there is hardly any re‐absorption of the blue emission by Mn2+ ions and the spectrum matches the commercial Ce3+‐doped yttrium aluminium garnet (YAG) phosphor coated over a blue LED. In addition, we have successfully incorporated the colloidal nanocrystals into a polymer matrix to make a nanocomposite as well as transparent films without altering the optical properties of the nanocrystals. The colloidal nanocomposite was coated over a UV LED to fabricate white LEDs. Finally, when the concentration of the dopant (Mn2+) ions was tuned the correlated color temperature (CCT) values varied between cool white light and daylight region.
Highly Sustainable Zinc Anodes for a Rechargeable Hybrid Aqueous Battery
Authors: Sun Kyung E. K. , Hoang Tuan K. A. , Doan The Nam Long , Yu Yan , Chen Pu 
Published: November 2017

AbstractThe synthesis of novel zinc electrodes has been successfully implemented by using the electroplating method with the aid of inorganic additives in the electroplating solution. The selected inorganic additives are indium sulfate, tin oxide, and boric acid. From X‐ray diffraction results, these synthesized zinc electrodes prefer (002) and/or (103) crystallographic orientations, representing basal morphology and high resistance to dendrite growth. The corrosion rates of these electroplated zinc samples decrease as much as 11 times smaller than the corrosion rate on zinc foil when the zinc materials are in contact with the aqueous electrolyte of a rechargeable hybrid aqueous battery (ReHAB). The ReHABs employing these anodes exhibit up to a threefold decrease in float charge current density after a seven‐day constant‐voltage charging at 2.1 V versus Zn2+/Zn. Furthermore, the capacity retention is up to 15 % higher than the performance of battery containing commercial Zn after 1000 cycles of charge–discharge. The significant advancements are attributed to the careful preparation of the anode, which contains appropriate crystallographic orientation and morphology.
Resolving a Reactive Organometallic Intermediate from Dynamic Directing Group Systems by Selective C−H Activation
Authors: Schaufelberger Fredrik , Timmer Brian J. J. , Ramström Olof 
Published: November 2017

AbstractCatalyst discovery from systems of potential precursors is a challenging endeavor. Herein, a new strategy applying dynamic chemistry to the identification of catalyst precursors from C−H activation of imines is proposed and evaluated. Using hydroacylation of imines as a model reaction, the selection of an organometallic reactive intermediate from a dynamic imine system, involving many potential directing group/metal entities, is demonstrated. The identity of the amplified reaction intermediate with the best directing group could be resolved in situ by ESI‐MS, and coupling of the procedure to an iterative deconvolution protocol generated a system with high screening efficiency.
Transcriptional alterations in hereditary and sporadic nonfunctioning pancreatic neuroendocrine tumors according to genotype
Authors: Keutgen Xavier M. , Kumar Suresh , Gara Sudheer , Boufraqech Myriem , Agarwal Sunita , Hruban Ralph H. , Nilubol Naris , Quezado Martha , Finney Richard , Cam Maggie , Kebebew Electron 
Published: November 2017

BACKGROUNDNonfunctioning pancreatic neuroendocrine tumors (NFPanNETs) may be sporadic or inherited because of germline mutations associated with von Hippel‐Lindau disease (VHL) or multiple endocrine neoplasia type 1 (MEN1). The clinical behavior of NFPanNETs is difficult to predict, even in tumors of the same stage and grade. The authors analyzed genotype‐specific patterns of transcriptional messenger RNA (mRNA) levels of NFPanNETs to understand the molecular features that determine PanNET phenotype.METHODSThirty‐two samples were included for genome‐wide mRNA gene expression analysis (9 VHL‐associated, 10 MEN1‐associated, and 9 sporadic NFPanNETs and 4 purified normal islet cell [NIC] samples). Validation of genes was performed by real‐time polymerase chain reaction analysis and immunohistochemistry. Gene expression profiles were analyzed by tumor genotype, and pathway analysis was curated.RESULTSConsensus clustering of mRNA expression revealed separate clustering of NICs, VHL‐associated NFPanNETs, and MEN1‐associated NFPanNETs; whereas some sporadic tumors clustered with MEN1. Four of 5 MEN1‐like sporadic PanNET subtypes had loss of heterozygosity at the MEN1 gene locus. Pathway analysis demonstrated subtype‐specific pathway activation, comprising angiogenesis and immune response in VHL; neuronal development in MEN1; protein ubiquitination in the new MEN1/sporadic subtype; and cytokinesis and cilium/microtubule development in sporadic NFPanNETs. Among many genes, platelet‐derived growth factor receptor β (PDGFRB), lymphoid enhancer‐binding factor‐1 (Lef‐1), cyclin‐dependent kinase 4 (CDK4), and CDK6 were upregulated in VHL or MEN1 NFPanNETs, providing potential subtype‐specific treatment targets.CONCLUSIONSDistinct mRNA expression patterns were identified in sporadic‐associated, VHL‐associated, and MEN1‐associated NFPanNETs. The current results uncover new pathways involved in NFPanNETs that are subtype‐specific and provide potential new diagnostic or therapeutic targets based on tumor subtype. Cancer 2018;124:636‐47. © 2017 American Cancer Society.