bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fabrication of micro‐meltblown filtration media using parallel plate die design
Authors: Hassan Mohammad Abouelreesh , Khan Saad A. , Pourdeyhimi Behnam 
Published: October 2015

ABSTRACTMeltblown fibers are typically produced using a die technology based on the slot concept, an extension of the sheet die technology with a series of holes substituting the center rectangular slot of the sheet die. While this prevalent technology has met with considerable success, an economical, facile design would be desirable. In this study a new parallel plate die concept to fabricate micro‐meltblown fibers that offers simplicity, ease of use, and low cost was examined. The new die concept had parallel plates forming channels for polymer melt to flow through with a set of air holes surrounding them. This die design produced meltblown fibrous media with fibers in the range of 3–10 μm with pore size between 20 and 60 microns. The underlying mechanisms leading to such large fiber size formation and its implication in air filtration performance has been discussed. While conventional meltblown die generates fibers of smaller diameter and webs with higher filtration efficiency than the parallel plate geometry, design modifications could enhance the parallel plate meltblown die performance and make it a viable alternative. These die adaptations that include reducing air flow resistance, increasing the number of air nozzles around the polymer nozzles, recessing the polymer spinnerets above the die face, and having inclined air channels to increase the drag force on the fibers has been discussed. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42998.
Outcomes in emergency general surgery following the introduction of a consultant-led unit
Authors: Shakerian R , Thomson B N , Gorelik A , Hayes I P , Skandarajah A R 
Published: October 2015

Abstract

Background
Patients presenting with emergency surgical conditions place significant demands on healthcare services globally. The need to improve emergency surgical care has led to establishment of consultant-led emergency surgery units. The aim of this study was to determine the effect of a changed model of service on outcomes.

Methods
A retrospective observational study of all consecutive emergency general surgical admissions in 2009–2012 was performed. A 2-year time frame before and after the establishment of the emergency general surgery (EGS) service was used to determine the number of admissions and operations, emergency department and hospital length of stay, as well as complication rates.

Results
The study included 7233 acute admissions. The EGS service managed 4468 patients (61·6 per cent increase) and performed 1804 operations (41·0 per cent increase). The most common diagnoses during the EGS period included acute appendicitis (532, 11·9 per cent), biliary disease (361, 8·1 per cent) and abdominal pain (561, 12·6 per cent). Appendicectomy (536, 29·7 per cent), cholecystectomy (239, 13·2 per cent) and laparotomy (226, 12·5 per cent) were the most commonly performed procedures. In the EGS period, time in the emergency department was reduced (from 8·0 to 6·0 h; P &lt; 0·001), as was length of hospital stay (from 3·0 to 2·0 days; P &lt; 0·001). The number of complications was reduced by 46·8 per cent, from 172 (6·2 per cent) to 147 (3·3 per cent) (P &lt; 0·001), with a 53 per cent reduction in the number of deaths in the EGS period, from 29 (16·9 per cent) to seven (8 per cent) (P = 0·039).

Conclusion
The establishment of a consultant-led emergency surgical service has been associated with improved provision of care, resulting in timely management and improved clinical outcomes.
Eupalitin induces apoptosis in prostate carcinoma cells through ROS generation and increase of caspase‐3 activity
Authors: Kaleem Sarjeel , Siddiqui Sahabjada , Siddiqui Hefazat Hussain , Badruddeen  , Hussain Arshad , Arshad Mohammad , Akhtar Juber , Rizvi Aleza 
Published: October 2015

AbstractProstate cancer is the second most common malignancy in the human reproductive system. Eupalitin is one of the O‐methylated flavonol‐exhibited enhanced cancer chemopreventive agents. The current study highlights the structural determination of eupalitin and aims to explore the antitumor activity of eupalitin in human prostate cancer cell (PC3) and its underlying mechanism. Eupalitin structure was determined by using FTIR, 1H NMR, and 13C NMR. PC3 cells were treated with increasing concentrations of eupalitin, followed by analysis of the cell viability with an MTT assay. The results demonstrated that eupalitin markedly inhibited the proliferation of PC3 cells in a concentration‐dependent manner. The results from fluorescent microscopic analysis of nuclear condensation and intracellular ROS generation determined that eupalitin significantly induced ROS level lead to nuclear apoptosis. Cell cycle analysis revealed that eupalitin‐induced cell cycle progression as a percentage of cells in G0/G1 phase decreased whereas S phase increased. Caspase‐3 immunofluorescence analysis confirms the efficacy of eupalitin‐inducing apoptotic pathway and cell death. Thus, our study is helpful in understanding the mechanism underlying these effects in prostate cancer and it may provide novel molecular targets for prostate cancer therapy.
Asymmetric Amination of Secondary Alcohols by using a Redox‐Neutral Two‐Enzyme Cascade
Authors: Chen Fei‐Fei , Liu You‐Yan , Zheng Gao‐Wei , Xu Jian‐He 
Published: October 2015

AbstractMultienzyme cascade approaches for the synthesis of optically pure molecules from simple achiral compounds are desired. Herein, a cofactor self‐sufficient cascade protocol for the asymmetric amination of racemic secondary alcohols to the corresponding chiral amines was successfully constructed by employing an alcohol dehydrogenase and a newly developed amine dehydrogenase. The compatibility and the identical cofactor dependence of the two enzymes led to an ingenious in situ cofactor recycling system in the one‐pot synthesis. The artificial redox‐neutral cascade process allowed the transformation of racemic secondary alcohols into enantiopure amines with considerable conversions (up to 94 %) and >99 % enantiomeric excess at the expense of only ammonia; this method thus represents a concise and efficient route for the asymmetric synthesis of chiral amines.
Selective Formation of Hägg Iron Carbide with g‐C3N4 as a Sacrificial Support for Highly Active Fischer–Tropsch Synthesis
Authors: Park Hunmin , Youn Duck Hyun , Kim Jae Young , Kim Won Yong , Choi Yo Han , Lee Young Hye , Choi Sun Hee , Lee Jae Sung 
Published: October 2015

AbstractThe Fischer–Tropsch synthesis (FTS) is a feasible pathway to chemicals and fuels from underutilized resources like coal, natural gas, biomass, and shale gas, instead of the current petroleum‐based production. Owing to its high activity and low price, the iron‐based catalysts are widely used in FTS, yet catalysts with higher activity and better selectivity should be developed for widespread applications. Herein, we report a unique strategy to synthesize an efficient iron catalyst for FTS by applying a graphitic carbon nitride (g‐C3N4) as a sacrificial support. The iron catalyst on g‐C3N4 is effectively reduced to a state that is rapidly and selectively converted to highly crystalline and pure Hägg carbide (χ‐Fe5C2) phase during the FTS reaction. The obtained catalyst exhibits outstanding CO conversion, and high selectivity for C5+ products, outperforming most of the recently reported carbon‐based iron catalysts.
Biofunctionalization of Polyoxometalates with DNA Primers, Their Use in the Polymerase Chain Reaction (PCR) and Electrochemical Detection of PCR Products
Authors: Debela Ahmed M. , Ortiz Mayreli , Beni Valerio , Thorimbert Serge , Lesage Denis , Cole Richard B. , O'Sullivan Ciara K. , Hasenknopf Bernold 
Published: October 2015

AbstractThe bioconjugation of polyoxometalates (POMs), which are inorganic metal oxido clusters, to DNA strands to obtain functional labeled DNA primers and their potential use in electrochemical detection have been investigated. Activated monooxoacylated polyoxotungstates [SiW11O39{Sn(CH2)2CO}]8− and [P2W17O61{Sn(CH2)2CO}]6− have been used to link to a 5′‐NH2 terminated 21‐mer DNA forward primer through amide coupling. The functionalized primer was characterized by using a battery of techniques, including electrophoresis, mass spectrometry, as well as IR and Raman spectroscopy. The functionality of the POM‐labeled primers was demonstrated through hybridization with a surface‐immobilized probe. Finally, the labeled primers were successfully used in the polymerase chain reaction (PCR) and the PCR products were characterized by using electrophoresis.
CH Bond Activation by Early Transition Metal Carbide Cluster Anion MoC3−
Authors: Li Zi‐Yu , Hu Lianrui , Liu Qing‐Yu , Ning Chuan‐Gang , Chen Hui , He Sheng‐Gui , Yao Jiannian 
Published: October 2015

AbstractAlthough early transition metal (ETM) carbides can activate CH bonds in condensed‐phase systems, the electronic‐level mechanism is unclear. Atomic clusters are ideal model systems for understanding the mechanisms of bond activation. For the first time, CH activation of a simple alkane (ethane) by an ETM carbide cluster anion (MoC3−) under thermal‐collision conditions has been identified by using high‐resolution mass spectrometry, photoelectron imaging spectroscopy, and high‐level quantum chemical calculations. Dehydrogenation and ethene elimination were observed in the reaction of MoC3− with C2H6. The CH activation follows a mechanism of oxidative addition that is much more favorable in the carbon‐stabilized low‐spin ground electronic state than in the high‐spin excited state. The reaction efficiency between the MoC3− anion and C2H6 is low (0.23±0.05) %. A comparison between the anionic and a highly efficient cationic reaction system (Pt++C2H6) was made. It turned out that the potential‐energy surfaces for the entrance channels of the anionic and cationic reaction systems can be very different.
Insight into the Mechanism of the Initial Reaction of an OH Radical with DNA/RNA Nucleobases: A Computational Investigation of Radiation Damage
Authors: Milhøj Birgitte O. , Sauer Stephan P. A. 
Published: October 2015

AbstractEarlier theoretical investigations of the mechanism of radiation damage to DNA/RNA nucleobases have claimed OH radical addition as the dominating pathway based solely on energetics. In this study we supplement calculations of energies with the kinetics of all possible reactions with the OH radical through hydrogen abstraction and OH radical addition onto carbon sites, using DFT at the ωB97X‐D/6‐311++G(2df,2pd) level with the Eckart tunneling correction. The overall rate constants for the reaction with adenine, guanine, thymine, and uracil are found to be 2.17×10−12, 5.64×10−11, 2.01×10−11, and 5.03×10−12 cm3 molecules−1 s−1, respectively, which agree exceptionally well with experimental values. We conclude that abstraction of the amine group hydrogen atoms competes with addition onto C8 as the most important reaction pathway for the purine nucleobases, while for the pyrimidine nucleobases addition onto C5 and C6 competes with the abstraction of H1. Thymine shows favourability against abstraction of methyl hydrogens as the dominating pathway based on rate constants. These mechanistic conclusions are partly explained by an analysis of the electrostatic potential together with HOMO and LUMO orbitals of the nucleobases.
Azobenzene C‐Nucleosides for Photocontrolled Hybridization of DNA at Room Temperature
Authors: Goldau Thomas , Murayama Keiji , Brieke Clara , Asanuma Hiroyuki , Heckel Alexander 
Published: October 2015

AbstractHerein, we report the reversible light‐regulated destabilization of DNA duplexes by using azobenzene C‐nucleoside photoswitches. The incorporation of two different azobenzene residues into DNA and their photoswitching properties are described. These new residues demonstrate a photoinduced destabilization effect comparable to the widely applied D‐threoninol‐linked azobenzene switch, which is currently the benchmark. The photoswitches presented herein show excellent photoswitching efficiencies in DNA duplexes – even at room temperature – which are superior to commonly used azobenzene‐based nucleic acid photoswitches. In addition, these photoswitching residues exhibit high thermal stability and excellent fatigue resistance, thus rendering them one of the most efficient candidates for the regulation of duplex stability with light.
Phase behaviour of sesame (Sesamum indicum L.) seed oil using supercritical CO2
Authors: Feihrmann Andresa Carla , Giufrida Willyan Machado , Saldaña Marleny D. A. , de Carvalho Lima Jéssica , Ferreira‐Pinto Leandro , Botelho José Rafael Santos , Cabral Vladimir Ferreira , de Carvalho Junior Raul Nunes , Corazza Marcos Lúcio , Cardozo‐Filho Lucio 
Published: October 2015

ABSTRACTNew experimental data were measured for phase transition of the binary system CO2 + black sesame oil. A variable volume cell was employed using the static synthetic method in a temperature range of 303–333 K, pressures up to 20 MPa, and CO2 mass fractions between 0.12–0.39 g/g. For mass fractions > 0.39, phase transition data were not measured due to pressure limitations of the high‐pressure system used. Vapour‐liquid transitions (VLE) of bubble point (BP) were determined. Phase transition data of CO2 + black sesame oil were compared to reported data from the literature involving CO2 and similar oils. The trend of the phase transition behaviour between all systems compared was similar. Phase equilibrium data obtained experimentally were successfully modelled with the Peng‐Robinson equation of state (PR‐EoS) combined with the van der Waals mixing rule (PR‐vdW2) and Wong‐Sandler mixing rule (PR‐WS).
Detection of the Elusive Triazane Molecule (N3H5) in the Gas Phase
Authors: Förstel Marko , Maksyutenko Pavlo , Jones Brant M. , Sun Bing‐Jian , Chen Shih‐Hua , Chang Agnes H.‐H. , Kaiser Ralf I. 
Published: October 2015

AbstractThe front cover artwork is provided by the groups of Prof. R. I. Kaiser (University of Hawaii) and Prof. A. H.‐H. Chang (National Dong Hwa University). The image shows a triazane molcule as it sublimes from irradiated ammonia ices along with its ion profile after photoionization; ammonia has been detected on Kuiper Belt Objects with Pluto being the most prominent member (courtesy NASA). Read the full text of the article at 10.1002/cphc.201500560
Dispersion of Polymers in Metallic Gallium
Authors: Kumar Vijay Bhooshan , Gedanken Aharon , Avnir David , Porat Ze'ev 
Published: October 2015

AbstractThis work examines the concept of dispersing polymers in metals. Herein, this was mainly studied with molten gallium, in which 5‐18 wt % of various short‐chain polymers were incorporated and mixed. The nature of the solidified products was examined by using X‐ray diffraction, electron microscopy, UV/Vis, differential scanning calorimetry, and thermal gravimetric analyses. It was found that some polymers can be dispersed as small domains within molten metals to form a heterogeneous solid. The ability to dope Ga with large polymers opens a new avenue to electronic materials.
Study of Multiporphyrin Compounds as Colorimetric Sitting‐Atop Metal Complexes: Synthesis and Photophysical Studies
Authors: Costa Joana I. T. , Oliveira Elisabete , Santos Hugo M. , Tomé Augusto C. , Neves Maria G. P. M. S. , Lodeiro Carlos 
Published: October 2015

AbstractMono‐, di‐, tri‐, and hexaporphyrin derivatives were synthesized and their sensorial ability toward Na+, Li+, Ca2+, Cu2+, Ni2+, Co2+, Fe3+, Zn2+, Cd2+, Hg2+, Ag+, Cr3+, Pb2+, and Al3+ was explored by absorption and emission spectroscopy and 1H NMR spectroscopy. For all of the studied porphyrin derivatives the most significant spectral changes were observed upon addition of Zn2+, Cd2+, Cu2+, Co2+, Pb2+, Hg2+, and Fe3+, which resulted in a color change from red to green. When the remaining metal ions were tested, no significant changes were observed. The results reveal, as expected, the formation of mononuclear complexes for porphyrin 4, dinuclear complexes for diporphyrin 7, and trinuclear complexes for triporphyrins 9 and 10. In addition, complexes of type M6L were determined for hexaporphyrin 8. The NMR spectroscopy studies suggest that the interaction with the metals occurs with the formation of sitting‐atop complexes. This study also shows that the sensitivity increases with increasing number of coordination sites, with the most pronounced case observed for Hg2+. The lowest value of detectable concentration of 0.05 μm for Hg2+ was achieved for hexaporphyrin 8.
A Self‐Assembling Octahedral Aggregate of Poly(methyl methacrylate) Nanospheres on a Silver Substrate
Authors: Chen Shaoyun , Hu Chenglong , Zhang Weihong , Chen Jian 
Published: October 2015

AbstractA large‐area, self‐assembling, octahedral aggregate composed of poly(methyl methacrylate) nanospheres (PMMA‐NS) was constructed by using a one‐step electrodeposition approach from an aqueous solution containing AgNO3 and PMMA‐NS as sacrificial electrolytes. The surface chain geometry of the product was revealed by Raman spectroscopy. The results revealed that the orientation of chains of the PMMA‐NS octahedron is different from that of the nonaggregated PMMA‐NS because of the interfacial interactions between the polymer chain and Ag metal. This can be explained by the crystal surface free energy of the octahedral Ag substrate, which gives rise to diverse conformations of the PMMA molecular chain at different surface regions of the silver substrate. In addition, the adsorptive properties of PMMA‐NS octahedra are such that the adsorbent–adsorbate system is cost‐effective, efficient and fast for the removal of dyes from contaminated wastewater.
Complex metacommunity structure for benthic invertebrates in a low‐diversity coastal system
Authors: Valanko Sebastian , Heino Jani , Westerbom Mats , Viitasalo Markku , Norkko Alf 
Published: October 2015

AbstractThe majority of studies in metacommunity ecology have focused on systems other than marine benthic ecosystems, thereby providing an impetus to broaden the focus of metacommunity research to comprise marine systems. These systems are more open than many other systems and may thus exhibit relatively less discrete patterns in community structure across space. Metacommunity structure of soft‐sediment benthic invertebrates was examined using a fine‐grained (285 sites) data set collected during one summer across a large spatial extent (1700 km2). We applied the elements of metacommunity structure (EMS) approach, allowing multiple hypothesis of variation in community structure to be tested. We demonstrated several patterns associated with environmental variation and associated processes that could simultaneously assemble species to occur at the sites. A quasi‐Clementsian pattern was observed frequently, suggesting interdependent ecological relationships among species or similar response to an underlying environmental gradient across sites. A quasi‐nested clumped species loss pattern was also observed, which suggests nested habitat specialization. Species richness declined with depth (from 0.5 to 44.8 m). We argue that sensitive species may survive in shallower water, which are more stable with regard to oxygen conditions and present greater habitat complexity, in contrast to deeper waters, which may experience periodic disturbance due to hypoxia. Future studies should better integrate disturbance in terms of temporal dynamics and dispersal rates in the EMS approach. We highlight that shallow water sites may act as sources of recruitment to deeper water sites that are relatively more prone to periodic disturbances due to hypoxia. However, these shallow sites are not currently monitored and should be better prioritized in future conservation strategies in marine systems.
Illegal tusk harvest and the decline of tusk size in the African elephant
Authors: Chiyo Patrick I. , Obanda Vincent , Korir David K. 
Published: October 2015

SummaryHarvesting of wild populations can cause the evolution of morphological, behavioral, and life history traits that may compromise natural or sexual selection. Despite the vulnerability of large mammals to rapid population decline from harvesting, the evolutionary effects of harvesting on mega‐fauna have received limited attention. In elephants, illegal ivory harvesting disproportionately affects older age classes and males because they carry large tusks, but its' effects on tusk size for age or tusk size for stature are less understood. We tested whether severe historical elephant harvests eliminated large tuskers among survivors and whether elephants born thereafter had smaller tusks. Adjusting for the influence of shoulder height – a metric strongly correlated with body size and age and often used as a proxy for age – we compared tusk size for elephants sampled in 1966–1968, prior to severe ivory harvesting in the late 1970s and early 1980s, with tusk size of survivors and elephants born during population recovery in the mid‐1990s. In a regional population, tusk length declined by ˜21% in male and by ˜27% in female elephants born during population recovery, while tusk length declined by 22% in males and 37% in females among survivors. Tusk circumference at lip declined by 5% in males but not in females born during population recovery, whereas tusk circumference reduced by 8% in male and by 11% in female survivors. In a single subpopulation, mean tusk length at mean basal tusk circumference declined by 12.4% in males and 21% in females. Tusk size varied between elephant social groups. Tusk homogeneity within social groups and the often high genetic similarity within social groups suggest that tusk size may be heritable. Our findings support a hypothesis of selection of large tuskers by poachers as a driver of the decline in tusk size for age proxy and contemporary tusk evolution in African elephants.
Facile Preparation of 2,6‐Pyridinedicarb­oxylic Acid Protected Gold Nanoparticles with Sensitive Chromium‐Ion Sensing and Efficient Catalysis
Authors: Yang Xin , Fu Shanshan , Ren Guojuan , Chai Fang , Qu Fengyu 
Published: October 2015

AbstractThe detection of Cr3+ and Cr6+ ions is very important as they are dangerous pollutants and carcinogens. Herein, we describe the preparation of 2,6‐pyridinedicarboxylic acid functionalized gold nanoparticles (PDCA–AuNPs) and their application as colorimetric sensors for the detection of Cr3+ and Cr6+ ions in water samples. The PDCA–AuNPs could be induced to aggregate quickly in the presence of Cr3+ ions, and the aggregation can be observed through the colorimetric response and special localized surface plasmon resonance (LSPR) of the gold nanoparticles. A linear response to the concentration of Cr3+ ions was observed from 10 nM to 1 μM. The detection limit is as low as 2 nM, which is below the maximum recommended contamination level of the World Health Organization for the chromium content (0.962 μM) in drinking water. The highly specific interactions of Cr3+ ions with PDCA–AuNPs provided excellent selectivity towards the detection of Cr3+ ions over other metal ions (Pb2+, Mg2+, Zn2+, Ni2+, Cu2+, Co2+, Ca2+, Mn2+, Fe2+, Cd2+, Ba2+, Cr6+, Ag+, Fe3+, Al3+, and Hg2+). Additionally, Cr6+ ions can be determined through the detection of Cr3+ ions after reduction by ascorbic acid. This method can offer the additional advantage of the efficient detection of Cr3+ and Cr6+ ions over other ions in environmental lake water. Additionally, the PDCA–AuNPs can be used as an efficient catalyst for the reduction of 4‐nitrophenol (4‐NP) and K3[Fe(CN)6].