bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficient Deep‐Blue Electroluminescence Based on Phenanthroimidazole‐Dibenzothiophene Derivatives with Different Oxidation States of the Sulfur Atom
Authors: Tang Xiangyang , Shan Tong , Bai Qing , Ma Hongwei , He Xin , Lu Ping 
Published: January 2017

AbstractDeveloping efficient deep‐blue materials is a long‐term research focus in the field of organic light‐emitting diodes (OLEDs). In this paper, we report two deep‐blue molecules, PITO and PISF, which share similar chemical structures but exhibit different photophysical and device properties. These two molecules consist of phenanthroimidazole and dibenzothiophene analogs. The distinction of their chemical structures lies in the different oxidation states of the S atom. For PITO, the S atom is oxidized and the resulting structure dibenzothiophene S,S‐dioxide becomes electron deficient. Therefore, PITO displays remarkable solvatochromism, implying a charge‐transfer (CT) excited state formed between the donor (D) phenanthroimidazole and acceptor (A) dibenzothiophene S,S‐dioxide. For PISF, it is constituted of phenanthroimidazole and dibenzothiophene in which the S atom is not oxidized. PISF displays locally excited (LE) emission with little solvatochromism. Compared with PISF, the D–A molecule PITO with an electron‐deficient group shows a much lower LUMO energy level, which is in favor of electron injection in device. In addition, PITO exhibits more balanced carrier transport. However, PISF is capable of emitting in the shorter wavelength region, which is beneficial to obtain better color purity. The doped electroluminescence (EL) device of the D–A molecule PITO manifests deep‐blue emission with CIE coordinates of (0.15, 0.08) and maximum external quantum efficiency (EQE) of 4.67 %. The doped EL device of the LE molecule PISF, however, reveals an even bluer emission with CIE coordinates of (0.15, 0.06) and a maximum EQE of 4.08 %.
Sensitizers for Aqueous‐Based Solar Cells
Authors: Li Chun‐Ting , Lin Ryan Yeh‐Yung , Lin Jiann T. 
Published: January 2017

AbstractAqueous dye‐sensitized solar cells (DSSCs) are attractive due to their sustainability, the use of water as a safe solvent for the redox mediators, and their possible applications in photoelectrochemical water splitting. However, the higher tendency of dye leaching by water and the lower wettability of dye molecules are two major obstacles that need to be tackled for future applications of aqueous DSSCs. Sensitizers designed for aqueous DSSCs are discussed based on their functions, such as modification of the molecular skeleton and the anchoring group for better stability against dye leaching by water, and the incorporation of hydrophilic entities into the dye molecule or the addition of a surfactant to the system to increase the wettability of the dye for more facile dye regeneration. Surface treatment of the photoanode to deter dye leaching or improve the wettability of the dye molecule is also discussed. Redox mediators designed for aqueous DSSCs are also discussed. The review also includes quantum‐dot‐sensitized solar cells, with a focus on improvements in QD loading and suppression of interfacial charge recombination at the photoanode.
Insights into the interaction of methotrexate and human serum albumin: A spectroscopic and molecular modeling approach
Authors: Cheng Li‐Yang , Fang Min , Bai Ai‐Min , Ouyang Yu , Hu Yan‐Jun 
Published: January 2017

AbstractIn this study, fluorescence spectroscopy and molecular modeling approaches were employed to investigate the binding of methotrexate to human serum albumin (HSA) under physiological conditions. From the mechanism, it was demonstrated that fluorescence quenching of HSA by methotrexate results from the formation of a methotrexate/HSA complex. Binding parameters calculated using the Stern–Volmer method and the Scatchard method showed that methotrexate binds to HSA with binding affinities in the order 104 L·mol−1. Thermodynamic parameter studies revealed that the binding reaction is spontaneous, and that hydrogen bonds and van der Waals interactions play a major role in the reaction. Site marker competitive displacement experiments and a molecular modeling approach demonstrated that methotrexate binds with appropriate affinity to site I (subdomain IIA) of HSA. Furthermore, we discuss some factors that influence methotrexate binding to HSA.
Hydrocarbon‐stapled lipopeptides exhibit selective antimicrobial activity
Authors: Jenner Zachary B. , Crittenden Christopher M. , Gonzalez Martín , Brodbelt Jennifer S. , Bruns Kerry A. 
Published: January 2017

AbstractAntimicrobial peptides (AMPs) occur widely in nature and have been studied for their therapeutic potential. AMPs are of interest due to the large number of possible chemical structural combinations using natural and unnatural amino acids, with varying effects on their biological activities. Using physicochemical properties from known naturally occurring amphipathic cationic AMPs, several hydrocarbon‐stapled lipopeptides (HSLPs) were designed, synthesized, and tested for antimicrobial properties. Peptides were chemically modified by N‐terminal acylation, C‐terminal amidation, and some were hydrocarbon stapled by intramolecular olefin metathesis. The effects of peptide length, amphipathic character, and stapling on antimicrobial activity were tested against Escherichia coli, three species of Gram‐positive bacteria (Staphylococcus aureus, Bacillus megaterium, and Enterococcus faecalis), and two strains of Candida albicans. Peptides were shown to disrupt liposomes of different phospholipid composition, as measured by leakage of a fluorescent compound from vesicles. Peptides with (S)−2‐(4′‐pentenyl)‐alanine substituted for l‐alanine in a reference peptide showed a marked increase in antimicrobial activity, hemolysis, and membrane disruption. Stapled peptides exhibited slightly higher antimicrobial potency; those with greatest hydrophobic character showed the greatest hemolysis and liposome leakage, but lower antimicrobial activity. The results support a model of HSLPs as membrane‐disruptive AMPs with potent antimicrobial activity and relatively low hemolytic potential at biologically active peptide concentrations.
Randomized clinical trial of preoperative dexamethasone on postoperative nausea and vomiting after laparoscopy for suspected appendicitis
Authors: Kleif J , Kirkegaard A , Vilandt J , Gögenur I 
Published: January 2017

Abstract

Background
Few studies have investigated the effects of preoperative dexamethasone in acute surgical patients. This study examined the effects of 8 mg dexamethasone administered intravenously 30 min before surgery for suspected acute appendicitis.

Methods
A multicentre, parallel-group, double-blind, placebo-controlled study was conducted at two university hospitals in Denmark. Adults undergoing laparoscopic surgery for suspected appendicitis were eligible for inclusion. Participants, healthcare staff and investigators were blinded until all data analysis had been done. The primary outcome was the incidence of postoperative nausea and vomiting (PONV) during the first postoperative day. Secondary outcomes were pain, fatigue, sleep, opioid consumption, use of antiemetics, quality of recovery and duration of convalescence. Analysis was done according to the intention-to-treat principle.

Results
A total of 120 patients were enrolled; 57 patients in the dexamethasone group and 59 in the placebo group were eligible for primary analysis. In the dexamethasone group, 47 (95 per cent c.i. 35 to 60) per cent of patients experienced PONV compared with 63 (50 to 74) per cent) in the placebo group. The absolute risk reduction in PONV was 15 (–3 to 33) per cent in favour of the dexamethasone group (P = 0·098). Patients in the dexamethasone group had less pain at rest (difference in score on visual analogue scale (VAS) 9 (95 per cent c.i. 1 to 17) mm; P = 0·024), were less fatigued (difference in VAS score 7 (0 to 14) mm; P = 0·038), used fewer opioids (absolute risk reduction 17 (2 to 33) per cent; P = 0·033) and had better quality of recovery (difference in QoR-15 score 13 (4 to 22); P = 0·006) during the first postoperative day. There was no difference in postoperative complications (P = 0·595).

Conclusion
Preoperative dexamethasone did not reduce PONV by the target level of 50 per cent. Registration number: NCT02415335 (http://www.clinicaltrials.gov).
Alendronate‐anchored PEGylation of ceria nanoparticles promotes human hepatoma cell proliferation via AKT/ERK signaling pathways
Authors: Cheng Heng , Liao Zhong‐Li , Ning Lin‐Hong , Chen Hong‐Yan , Wei Shan‐Shan , Yang Xiao‐Chao , Guo Hong 
Published: January 2017

AbstractPrevious work has suggested that ceria nanoparticles (CNPs) have regenerative antioxidant properties, which have motivated researchers to consider CNPs as therapeutic agents for treating a number of diseases, including cancer. Recent studies have shown CNPs to be toxic to cancer cells, to inhibit invasion and sensitize cancer cells to radiotherapy. In addition, several hydrophilic polymers have been used to coat the CNP surface in order to enhance its properties of extensive biocompatibility and systemic nontoxicity to normal cells and tissues. However, the results of previous studies were based on high CNP doses (10 μg/mL or more), and these doses may cause serious side effects in clinical applications. The impact of low CNP doses on tumor cells remains unknown. In this study, we report experiments indicating that CNPs‐AL‐ polyethylene glycol (PEG)600, a type of surface‐modified CNP that is more stable and less toxic than traditional CNPs could promote proliferation of hepatoma cells in a dose‐dependent manner. In addition, further research showed that a low dose (0.01 μg/mL) of CNPs‐AL‐PEG600 could reduce hepatoma cell apoptosis and activate AKT/ERK signaling pathways. These results may provide information that is important for using CNPs‐AL‐PEG600 as a therapeutic agent in clinical cancer treatments.
Bio‐orthogonal Fluorescent Labelling of Biopolymers through Inverse‐Electron‐Demand Diels–Alder Reactions
Authors: Kozma Eszter , Demeter Orsolya , Kele Péter 
Published: January 2017

AbstractBio‐orthogonal labelling schemes based on inverse‐electron‐demand Diels–Alder (IEDDA) cycloaddition have attracted much attention in chemical biology recently. The appealing features of this reaction, such as the fast reaction kinetics, fully bio‐orthogonal nature and high selectivity, have helped chemical biologists gain deeper understanding of biochemical processes at the molecular level. Listing the components and discussing the possibilities and limitations of these reagents, we provide a recent snapshot of the field of IEDDA‐based biomolecular manipulation with special focus on fluorescent modulation approaches through the use of bio‐orthogonalized building blocks. At the end, we discuss challenges that need to be addressed for further developments in order to overcome recent limitations and to enable researchers to answer biomolecular questions in more detail.
Friedel–Crafts Alkylation of Indoles with Nitroalkenes through Hydrogen‐Bond‐Donating Metal–Organic Framework
Authors: Rao Purna Chandra , Mandal Sukhendu 
Published: January 2017

AbstractUrea‐derived hydrogen‐bond‐donating (HBD) catalysts are good catalysts for organic transformations. Usually, urea derivatives undergo self‐recognition and aggregation during homogeneous catalytic processes. To avoid this, a new approach involving the incorporation of urea moieties into metal–organic frameworks (MOFs) was recently developed. Herein, we synthesized a new porous, zinc‐based MOF by using ureylenic acid that acts as a hydrogen‐bond‐donating catalyst. According to our knowledge, the pores of this MOF are larger than those of other reported HBD‐derived MOFs and, as such, can accommodate large substrates that typically cannot access the pores of other HBD‐based MOFs for the Friedel–Crafts reaction.
High‐Rate Capable Full‐Cell Lithium‐Ion Battery based on a Conversion Anode and an Intercalation Cathode
Authors: Veluri Pavan S. , Mitra Sagar 
Published: January 2017

AbstractPorous Fe2O3 nanostructures are synthesized by using a simple polyol method and used as an anode along with commercial‐grade LiCoO2 as the cathode to study full‐cell lithium‐ion battery applications. The half‐cell performance of Fe2O3 exhibits a high reversible capacity of 903 mAh/g at 1C rate. Commercial LiCoO2 also delivers a stable capacity of 131 mAh/g at 1C rate after 50 cycles. A full cell is constructed by using Fe2O3 anode and LiCoO2 cathode, and the mass loadings are adjusted such that no pre‐activation is required. The as‐constructed LiCoO2‐Fe2O3 full cell exhibits a stable capacity of 800 mAh/g (capacity based on anode mass) at 1C after 100 charge‐discharge cycles with 91 % capacity retention. The rate capability test shows that the full cell is high rate capable and could withstand high currents up to 5C. A pouch cell (300 mAh, 3 V nominal voltage) is constructed with Fe2O3 anode and LiCoO2 cathode, and is demonstrated to power a solar study lamp (aimed for rural application) and an ultra‐bright LED array (50 ultra‐bright LEDs, with 3 V and 50 mA ratings for a single LED).
Highly Conformationally Restricted Cyclopropane Tethers with Three‐Dimensional Structural Diversity Drastically Enhance the Cell Permeability of Cyclic Peptides
Authors: Matsui Kouhei , Kido Yasuto , Watari Ryosuke , Kashima Yousuke , Yoshida Yutaka , Shuto Satoshi 
Published: January 2017

AbstractInvited for the cover of this issue is the group of Kouhei Matsui and Satoshi Shuto at Shionogi & Co.,Ltd. and at Hokkaido University. The image depicts the cyclopropane tethers with three‐dimensional structural diversity that are able to remarkably change the conformation and physicochemical properties of cyclic peptides due to the characteristic steric feature of cyclopropane. Read the full text of the article at 10.1002/chem.201604946.
Bernstein approximations in glasso‐based estimation of biological networks
Authors: Purutçuoğlu Vilda , Ağraz Melih , Wit Ernst 
Published: January 2017

AbstractThe Gaussian graphical model (GGM) is one of the common dynamic modelling approaches in the construction of gene networks. In inference of this modelling the interaction between genes can be detected mainly via graphical lasso (glasso) or coordinate descent‐based approaches. Although these methods are successful in moderate networks, their performances in accuracy decrease when the system becomes sparser. We here implement a particular type of polynomial transformations, called the Bernstein polynomials, of the network data in advance of their inference to raise the accuracy. From comparative Monte Carlo studies and real data analyses we show that these polynomials are successful in terms of the precision, specificity and F‐measure when the scale‐free networks are modelled via GGM and estimated by glasso, and accordingly they can be used as a preprocessing step in inference of these networks. The Canadian Journal of Statistics 45: 62–76; 2017 © 2017 Statistical Society of Canada
Geometry‐Controlled Photoinduced Charge Separation and Recombination in a Trans‐A2B2‐Functionalized Donor–Acceptor Conjugate Composed of a Multimodular Zinc Porphyrin and Fullerene
Authors: Benitz Alejandro , Thomas Michael B. , D'Souza Francis 
Published: January 2017

AbstractThe front cover artwork is provided by the D′Souza group at the Department of Chemistry, University of North Texas. The image shows the optimized structure of a trans‐A2B2‐functionalized multimodular zinc porphyrin/fullerene supramolecular donor–acceptor conjugate and the geometry‐governed photochemical events which occur upon photoexcitation of the porphyrin. Read the full text of the article at 10.1002/cptc.201600017.
Expression of CD43 in chronic lymphoproliferative leukemias
Authors: Sorigue Marc , Juncà Jordi , Sarrate Edurne , Grau Javier 
Published: January 2017

BackgroundCD43 has been used on histological samples for the differential diagnosis of lymphoproliferative disorders but there is scarce data on its use by flow cytometry (FC). We set out to characterize the expression of CD43 by FC in B‐cell lymphoproliferative disorders and to determine its possible role in the differential diagnosis of these malignancies.MethodsWe analyzed the expression of CD43 in clonal B‐cell lymphoproliferative disorders with exclusive peripheral blood and/or bone marrow involvement based on their Moreau chronic lymphocytic leukemia (CLL) score with particular emphasis on Moreau CLL score 3 (MS3) cases, which often present a diagnostic challenge. The cohort included 433 CLL (score 4–5), 34 MS3 and 166 lymphoproliferative disorders with lower scores.ResultsGenerally, the higher the Moreau CLL score, the higher CD43‐positivity (425/443 [96%] for CLL, 23/34 [67%] for MS3 and 18/166 [11%] for cases with lower scores). MS3 cases constituted 5.4% of all cases and were more frequently CD5, CD200, CD43‐positive and had del(q13) than score 0–2 cases. Among MS3 cases, del(13q) cases were predominantly CD43‐positive (12/13).ConclusionsThe frequency of CD43‐positivity increases sharply with the Moreau score. MS3 cases seem to include both CLL and non‐CLL lymphoproliferative disorders and CD43 could aid in the differential diagnosis between the two. However, studies analyzing the correlation between CD43 expression and the underlying biologic changes of these cases are warranted. © 2017 International Clinical Cytometry Society
Links between soil microbial communities and plant traits in a species‐rich grassland under long‐term climate change
Authors: Sayer Emma J. , Oliver Anna E. , Fridley Jason D. , Askew Andrew P. , Mills Robert T. E. , Grime J. Philip 
Published: January 2017

AbstractClimate change can influence soil microorganisms directly by altering their growth and activity but also indirectly via effects on the vegetation, which modifies the availability of resources. Direct impacts of climate change on soil microorganisms can occur rapidly, whereas indirect effects mediated by shifts in plant community composition are not immediately apparent and likely to increase over time. We used molecular fingerprinting of bacterial and fungal communities in the soil to investigate the effects of 17 years of temperature and rainfall manipulations in a species‐rich grassland near Buxton,UK. We compared shifts in microbial community structure to changes in plant species composition and key plant traits across 78 microsites within plots subjected to winter heating, rainfall supplementation, or summer drought. We observed marked shifts in soil fungal and bacterial community structure in response to chronic summer drought. Importantly, although dominant microbial taxa were largely unaffected by drought, there were substantial changes in the abundances of subordinate fungal and bacterial taxa. In contrast to short‐term studies that report high resistance of soil fungi to drought, we observed substantial losses of fungal taxa in the summer drought treatments. There was moderate concordance between soil microbial communities and plant species composition within microsites. Vector fitting of community‐weighted mean plant traits to ordinations of soil bacterial and fungal communities showed that shifts in soil microbial community structure were related to plant traits representing the quality of resources available to soil microorganisms: the construction cost of leaf material, foliar carbon‐to‐nitrogen ratios, and leaf dry matter content. Thus, our study provides evidence that climate change could affect soil microbial communities indirectly via changes in plant inputs and highlights the importance of considering long‐term climate change effects, especially in nutrient‐poor systems with slow‐growing vegetation.
Predator effects on reef fish settlement depend on predator origin and recruit density
Authors: Benkwitt Cassandra E. 
Published: January 2017

AbstractDuring major life‐history transitions, animals often experience high mortality rates due to predation, making predator avoidance particularly advantageous during these times. There is mixed evidence from a limited number of studies, however, regarding how predator presence influences settlement of coral‐reef fishes and it is unknown how other potentially mediating factors, including predator origin (native vs. nonnative) or interactions among conspecific recruits, mediate the non‐consumptive effects of predators on reef fish settlement. During a field experiment in the Caribbean, approximately 52% fewer mahogany snapper (Lutjanus mahogoni) recruited to reefs with a native predator (graysby grouper, Cephalopholis cruentata) than to predator‐free control reefs and reefs with an invasive predator (red lionfish, Pterois volitans) regardless of predator diet. These results suggest that snapper recruits do not recognize nonnative lionfish as a threat. However, these effects depended on the density of conspecific recruits, with evidence that competition may limit the response of snapper to even native predators at the highest recruit densities. In contrast, there was no effect of predator presence or conspecific density on the recruitment of bicolor damselfish (Stegastes partitus). These context‐dependent responses of coral‐reef fishes to predators during settlement may influence individual survival and shape subsequent population and community dynamics.
Spatial heterogeneity can resolve the nitrogen paradox of tropical forests
Authors: Menge Duncan N. L. , Levin Simon A. 
Published: January 2017

AbstractMany tropical forests are characterized by large losses of plant‐available forms of nitrogen (N), indicating that they are N rich, and by an abundance of plants capable of symbiotic N fixation. These N‐fixing plants can fix enough N to drive N richness. However, biological N fixation (BNF) is more expensive than using plant‐available N, so sustained BNF in N‐rich soils appears to be a paradox. Here, we use spatially explicit ecosystem models to analyze the conditions under which spatial heterogeneity can induce simultaneous BNF and loss of plant‐available N (hereafter, we call this combination “N‐rich BNF”). Spatial movement of litter to neighboring plants’ rooting zones can maintain N‐rich BNF under a variety of conditions. For example, when N‐fixers have higher N demand than non‐fixers, N‐fixers export N‐rich litter to non‐fixers, inducing large losses of plant‐available N from the ecosystem, and receive N‐poor litter from non‐fixers, inducing BNF. BNF and N loss fluxes increase in proportion to the ratio of N‐fixer litter N:P to non‐fixer litter N:P, and also in proportion to the fraction of litter transferred out of a tree's rooting zone. Stoichiometric variability augments N‐rich BNF, as does increasing the fraction of the landscape occupied by N‐fixers, at least when they are rare. On the contrary, greater root overlap between neighbors and clumping of N‐fixers diminish N‐rich BNF. Finally, we examined how spatial litter transfer interacts with another mechanism that can sustain N‐rich BNF, incomplete down‐regulation of BNF. Spatial transfer and incomplete down‐regulation can both sustain N‐rich BNF, but they are compensatory rather than additive. These mechanisms can be distinguished by examining where N losses occur. Incomplete down‐regulation of BNF leads to greater N loss under N‐fixing trees, whereas spatial litter transfer leads to greater N loss under non‐fixing trees. Along with time lags in regulating BNF, these results comprise a series of hypotheses that could help understand the N paradox of tropical forests.