bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Antimicrobial Activity of Mononuclear Ruthenium(II) Complexes Containing the dppz Ligand
Authors: Liu Xuewen , Sun Biyun , Kell Ruby E. M. , Southam Hannah M. , Butler Jonathan A. , Li Xin , Poole Robert K. , Keene F. Richard , Collins J. Grant 
Published: March 2018

AbstractThe cis‐α isomer of [Ru(bb7)(dppz)]2+ (dppz=dipyrido[3,2‐a:2′,3′‐c]phenazine; bb7=bis[4(4′‐methyl‐2,2′‐bipyridyl)]‐1,7‐alkane) has been synthesised. The minimum inhibitory concentrations and the minimum bactericidal concentrations of [Ru(bb7)(dppz)]2+ and its parent complex [Ru(phen)2(dppz)]2+ (phen=1,10‐phenanthroline) were determined against a range of bacteria. The results showed that both ruthenium complexes exhibited good activity against Gram‐positive bacteria, but [Ru(bb7)(dppz)]2+ showed at least eightfold better activity against the Gram‐negative bacteria than [Ru(phen)2(dppz)]2+. Luminescence assays demonstrated that [Ru(bb7)(dppz)]2+ accumulated in a Gram‐negative bacterium to the same degree as in a Gram‐positive species, and assays with liposomes showed that [Ru(bb7)(dppz)]2+ interacted more strongly with membranes than the parent [Ru(phen)2(dppz)]2+ complex. The DNA binding affinity for [Ru(bb7)(dppz)]2+ was determined to be 6.7 × 106 m−1. Although more toxic to eukaryotic cells than [Ru(phen)2(dppz)]2+, [Ru(bb7)(dppz)]2+ exhibited greater activity against bacteria than eukaryotic cells.
Facile Synthesis of a Ternary Metal Hydroxide with Acid Treatment as an Effective and Durable Electrocatalyst in Water Oxidation
Authors: Wu Xiujuan , Xing Tongyu , Zhao Yimeng , Lee Husileng , Zhang Peili 
Published: March 2018

AbstractDeveloping low‐cost, effective, and durable oxygen‐evolution catalysts (OECs) is still a huge challenge owing to the uphill thermodynamic reaction and the involvement of a four‐electron and four‐proton kinetics process. Herein, a facilely prepared NiCoFe(OH)x/NiOOH/NF electrode affords current densities of 10 and 100 mA cm−2 at overpotentials of 223 and 254 mV, respectively, and a Tafel slope as low as 33.5 mV dec−1 in 1 m KOH, which is superior to NiCoFe(OH)x/NF electrodes electrodeposited with a traditional method. This electrode also displays surprisingly high durability at a current density of 50 mA cm−2 for over 50 hours under alkaline conditions. Component analysis and an electrochemical study revealed that the catalytic activity enhancement of this newly prepared electrode is mainly attributed to the formation of the electrically conductive NiOOH interlayer.
One‐Step Rapid and Scalable Flame Synthesis of Efficient WO3 Photoanodes for Water Splitting
Authors: Chen Hongjun , Bo Renheng , Tran‐Phu Thanh , Liu Guanyu , Tricoli Antonio 
Published: March 2018

AbstractPhotoelectrochemical water splitting is a promising approach for the carbon‐free production of hydrogen using sunlight. Here, robust and efficient WO3 photoanodes for water oxidation were synthesized by the scalable one‐step flame synthesis of nanoparticle aerosols and direct gas‐phase deposition. Nanostructured WO3 films with tunable thickness and band gap and controllable porosity were fabricated by controlling the aerosol deposition time, concentration, and temperature. Optimal WO3 films demonstrate superior water oxidation performance, reaching a current density of 0.91 mA at 1.24 V vs. reversible hydrogen electrode (RHE) and an incident photon‐to‐current conversion efficiency (IPCE) of ca. 61 % at 360 nm in 0.1 m H2SO4. Notably, it is found that the excellent performance of these WO3 nanostructures arises from the high in situ restructuring temperature (ca. 1000 °C), which increases oxygen vacancies and decreases charge recombination at the WO3/electrolyte interface. These findings provide a scalable approach for the fabrication of efficient photoelectrodes based on WO3 and other metal oxides for light‐driven water splitting.
Functionalization and Properties of Tetrahydronaphtho[2,1‐a]azulene Photoswitches
Authors: Sonne Kirstine , Lindbæk Broman Søren , Drøhse Kilde Martin , Ugleholdt Petersen Anne , Brøndsted Nielsen Mogen 
Published: March 2018

AbstractThe front cover artwork is provided by the group of Prof. Mogens Brøndsted Nielsen at the Department of Chemistry, University of Copenhagen (Denmark). This image shows the conversion between arylated tetrahydronaphtho[2,1‐a]azulenes and their ring‐opened isomers. Read the full text of the Article at 10.1002/cptc.201700213.
Diamine‐Functionalization of a Metal–Organic Framework Adsorbent for Superb Carbon Dioxide Adsorption and Desorption Properties
Authors: Lee Woo Ram , Kim Jeong Eun , Lee Sung Jin , Kang Minjung , Kang Dong Won , Lee Hwa Young , Hiremath Vishwanath , Seo Jeong Gil , Jin Hailian , Moon Dohyun , Cho Moses , Jung Yousung , Hong Chang Seop 
Published: March 2018

AbstractFor real‐world postcombustion applications in the mitigation of CO2 emissions using dry sorbents, adsorption and desorption behaviors should be controlled to design and fabricate prospective materials with optimal CO2 performances. Herein, we prepared diamine‐functionalized Mg2(dobpdc) (H4dobpdc=4,4′‐dihydroxy‐(1,1′‐biphenyl)‐3,3′‐dicarboxylic acid). (1‐diamine) with ethylenediamine (en), primary–secondary (N‐ethylethylenediamine—een and N‐isopropylethylenediamine—ipen), primary–tertiary, and secondary–secondary diamines. A slight alteration of the number of alkyl substituents on the diamines and their alkyl chain length dictates the desorption temperature (Tdes) at 100 % CO2, desorption characteristics, and ΔT systematically to result in the tuning of the working capacity. The existence of bulky substituents on the diamines improves the framework stability upon exposure to O2, SO2, and water vapor, relevant to real flue‐gas conditions. Bulky substituents are also responsible for an interesting two‐step behavior observed for the ipen case, as revealed by DFT calculations. Among the diamine‐appended metal–organic frameworks, 1‐een, which has the required adsorption and desorption properties, is a promising material for sorbent‐based CO2 capture processes. Hence, CO2 performance and framework durability can be tailored by the judicial selection of the diamine structure, which enables property design at will and facilitates the development of desirable CO2‐capture materials.
Photo‐Initiated Reduction of CO2 by H2 on Silica Surface
Authors: Liu Chao , Notestein Justin M. , Weitz Eric , Gray Kimberly A. 
Published: March 2018

AbstractInvited for this month's cover is the group of Prof. Kimberly Gray at Northwestern University. The Cover picture depicts a strategy to convert CO2 to CO selectively by vacuum UV photolysis via a chain radical mechanism. The Full Paper itself is available at 10.1002/cssc.201702341.
Joint server and network optimization toward load‐balanced service chaining
Authors: Thai Minh‐Tuan , Lin Ying‐Dar , Lai Yuan‐Cheng 
Published: March 2018

SummaryPrior service chaining systems address server and network load balancing issues individually, which may not ensure efficient system performance. To this end, in this paper, we study the design, implementation, complexity analysis, and evaluation of Nearest First and Local‐Global Transformation algorithm, which jointly supports server and network load balancing for chaining virtualized network functions (VNFs) in data center environment. The algorithm firstly constructs service chains by a greedy strategy, which both considers server and network latency. Then a searching technique, which replaces a selected VNF with another candidate and swaps the order of VNFs in service chains, is applied to improve the solutions. We have implemented the algorithm using Software‐defined networking and OpenFlow concepts. The numerical results indicate that, compared with a sequential approach, Nearest First and Local‐Global Transformation increases the system bandwidth utilization up to 45%. The results also show that it is worth applying the second phase of our algorithm since it considerably enhances the system performance by 20%.
Improving secret key generation for wireless communications in FDD mode
Authors: Allam Ali M. 
Published: March 2018

SummaryMost recent research on channel‐based key generation oriented to time division duplex system because the channel reciprocity feature is applied directly for secret key generation. Most of commercial cellular systems depend on frequency division duplex (FDD) systems. In this paper, we investigate the impact of uplink and downlink of FDD systems for the generation of shared secret keys between two parties in the presents of passive eavesdropper. In addition, we are considering improving the rate of the secret key for wireless communication in FDD mode. The main idea is to use the fading coefficient of the channels between the relay and other parties as an additional random common source for the secret key generation. Also, explore the using of channel estimation techniques to reduce the channel training sequence and study its effect on the generation of shared key for wireless communications in FDD mode. We derive the upper bound of the generated shared key rate for four scenarios and give numerical examples to reveal the performance of our suggested improvement approaches.
Regulation of C. elegans L4 cuticle collagen genes by the heterochronic protein LIN‐29
Authors: Abete‐Luzi Patricia , Eisenmann David M. 
Published: March 2018

AbstractThe cuticle, the outer covering of the nematode C. elegans, is synthesized five times during the worm's life by the underlying hypodermis. Cuticle collagens, the major cuticle component, are encoded by a large family of col genes and, interestingly, many of these genes express predominantly at a single developmental stage. This temporal preference motivated us to investigate the mechanisms underlying col gene expression and here we focus on a subset of col genes expressed in the L4 stage. We identified minimal promoter regions of <300 bp for col‐38, col‐49, and col‐63. In these regions, we predicted cis‐regulatory sequences and evaluated their function in vivo via mutagenesis of a col‐38p::yfp reporter. We used RNAi to study the requirement for candidate transcription regulators ELT‐1 and ELT‐3, LIN‐29, and the LIN‐29 co‐factor MAB‐10, and found LIN‐29 to be necessary for the expression of four L4‐specific genes (col‐38, col‐49, col‐63, and col‐138). Temporal misexpression of LIN‐29 was also sufficient to activate these genes at a different developmental stage. The LIN‐29 DNA‐binding domain bound the col‐38, col‐49, and col‐63 minimal promoters in vitro. For col‐38 we showed that the LIN‐29 sites necessary for reporter expression in vivo are also bound in vitro: this is the first identification of specific binding sites for LIN‐29 necessary for in vivo target gene expression.
Biodiversity matters in feedbacks between climate change and air quality: a study using an individual‐based model
Authors: Wang Bin , Shuman Jacquelyn , Shugart Herman H. , Lerdau Manuel T. 
Published: March 2018

AbstractAir quality is closely associated with climate change via the biosphere because plants release large quantities of volatile organic compounds (VOC) that mediate both gaseous pollutants and aerosol dynamics. Earlier studies, which considered only leaf physiology and simply scale up from leaf‐level enhancements of emissions, suggest that climate warming enhances whole forestVOCemissions, and these increasedVOCemissions aggravate ozone pollution and secondary organic aerosol formation. Using an individual‐based forestVOCemissions model,UVAFME‐VOC, that simulates system‐level emissions by explicitly simulating forest community dynamics to the individual tree level, ecological competition among the individuals of differing size and age, and radiative transfer and leaf function through the canopy, we find that climate warming only sometimes stimulates isoprene emissions (the single largest source of non‐methane hydrocarbon) in a southeasternU.S.forest. These complex patterns result from the combination of higher temperatures’ stimulating emissions at the leaf level but decreasing the abundance of isoprene‐emitting taxa at the community level by causing a decline in the abundance of isoprene‐emitting species (Quercusspp.). This ecological effect eventually outweighs the physiological one, thus reducing overall emissions. Such reduced emissions have far‐reaching implications for the climate–air‐quality relationships that have been established on the paradigm of warming‐enhancementVOCemissions from vegetation. This local scale modeling study suggests that community ecology rather than only individual physiology should be integrated into future studies of biosphere–climate–chemistry interactions.
Fish assemblage changes over half a century in the Yellow River, China
Authors: Xie Jia Yan , Tang Wen Jia , Yang Yu Hui 
Published: March 2018

AbstractRiverine environments have been threatened by anthropogenic perturbations worldwide, whereby their fish assemblages have been modified by habitat changes and nonendemic species invasions. We assessed changes in fish assemblages by comparing the species presence in historical and contemporary fish data in the Yellow River from 1965 to 2015. The temporal change in species assemblages was found with increased nonendemic species and fewer natives. Fish species richness of the river declined 35.4% over the past fifty years. Moreover, the decreased mean Bray–Curtis dissimilarity among reaches suggested that the fish assemblages of different reaches in the Yellow River were becoming more similar over time. However, temporal patterns of fish assemblages varied among reaches. In the upper Yellow River, higher species richness and more invasive species were found than those in the historical record, while the lower reaches experienced significant species loss. Dam constructions, exotic fish invasions, and flow reductions played the vital role in structuring the temporal fish assemblages in the Yellow River. It is suggested that river basins which experienced different types and levels of stressors by anthropogenic perturbations can produce varied effects on their temporal trends of species assemblages.
An in vitro evaluation of browser and grazer fermentation efficiency and microbiota using European moose spring and summer foods
Authors: Krizsan Sophie J. , Mateos‐Rivera Alejandro , Bertilsson Stefan , Felton Annika , Anttila Anne , Ramin Mohammad , Vaga Merko , Gidlund Helena , Huhtanen Pekka 
Published: March 2018

AbstractEvolutionary morphological and physiological differences between browsers and grazers contribute to species‐specific digestion efficiency of food resources. Rumen microbial community structure of browsers is supposedly adapted to characteristic nutrient composition of the diet source. If this assumption is correct, domesticated ruminants, or grazers, are poor model animals for assessing the nutritional value of food consumed by browsing game species. In this study, typical spring and summer foods of the European moose (Alces alces) were combined with rumen fluid collected from both dairy cows (Bos taurus) and from moose, with the aim of comparing fermentation efficiency and microbial community composition. The nutritional value of the food resources was characterized by chemical analysis and advanced in vitro measurements. The study also addressed whether or not feed evaluation based on in vitro techniques with cattle rumen fluid as inoculum could be a practical alternative when evaluating the nutritional value of plants consumed by wild browsers. Our results suggest that the fermentation characteristics of moose spring and summer food are partly host‐specific and related to the contribution of the bacterial phyla Firmicutes and Bacteriodetes to the rumen microbial community. Host‐specific adaptations of the ruminal microbial community structure could be explained from the evolutionary adaptations related to feeding habitats and morphophysiological differences between browsers and grazers. However, the observed overall differences in microbial community structure could not be related to ruminal digestion parameters measured in vitro. The in vitro evaluation of digestion efficiency reveals that equal amounts of methane were produced across all feed samples regardless of whether the ruminal fluid was from moose or dairy cow. The results of this study suggested that the nutritional value of browsers' spring and summer food can be predicted using rumen fluid from domesticated grazers as inoculum in in vitro assessments of extent of digestion when excluding samples of the white water lily root, but not of fermentation characteristics as indicated by the proportions of individual fermentation fatty acids to the total of volatile fatty acids.
Tropical herbivorous phasmids, but not litter snails, alter decomposition rates by modifying litter bacteria
Authors: Prather Chelse M. , Belovsky Gary E. , Cantrell Sharon A. , González Grizelle 
Published: March 2018

AbstractConsumers can alter decomposition rates through both feces and selective feeding in many ecosystems, but these combined effects have seldom been examined in tropical ecosystems. Members of the detrital food web (litter‐feeders or microbivores) should presumably have greater effects on decomposition than herbivores, members of the green food web. Using litterbag experiments within a field enclosure experiment, we determined the relative effects of common litter snails (Megalomastoma croceum) and herbivorous walking sticks (Lamponius portoricensis) on litter composition, decomposition rates, and microbes in a Puerto Rican rainforest, and whether consumer effects were altered by canopy cover presence. Although canopy presence did not alter consumers' effects, focal organisms had unexpected influences on decomposition. Decomposition was not altered by litter snails, but herbivorous walking sticks reduced leaf decomposition by about 50% through reductions in high quality litter abundance and, consequently, lower bacterial richness and abundance. This relatively unexplored but potentially important link between tropical herbivores, detritus, and litter microbes in this forest demonstrates the need to consider autotrophic influences when examining rainforest ecosystem processes.
Lipophilicity predicts the ability of nonsulphonylurea drugs to block pancreatic beta‐cell KATP channels and stimulate insulin secretion; statins as a test case
Authors: Real Joana , Miranda Caroline , Olofsson Charlotta S. , Smith Paul A. 
Published: March 2018

SummaryAimsKATP ion channels play a key role in glucose‐stimulated insulin secretion. However, many drugs block KATP as “off targets” leading to hyperinsulinaemia and hypoglycaemia. As such drugs are often lipophilic, the aim was to examine the relationship between drug lipophilicity (P) and IC50 for KATP block and explore if the IC50's of statins could be predicted from their lipophilicity and whether this would allow one to forecast their acute action on insulin secretion.Materials and methodsA meta‐analysis of 26 lipophilic, nonsulphonylurea, blockers of KATP was performed. From this, the IC50's for pravastatin and simvastatin were predicted and then tested experimentally by exploring their effects on KATP channel activity via patch‐clamp measurement, calcium imaging and insulin secretion in murine beta cells and islets.ResultsNonsulphonylurea drugs inhibited KATP channels with a Log IC50 linearly related to their logP. Simvastatin blocked KATP with an IC50 of 25 nmol/L, a value independent of cytosolic factors, and within the range predicted by its lipophilicity (21‐690 nmol/L). 10 μmol/L pravastatin, predicted IC50 0.2‐12 mmol/L, was without effect on the KATP channel. At 10‐fold therapeutic levels, 100 nmol/L simvastatin depolarized the beta‐cell membrane potential and stimulated Ca2+ influx but did not affect insulin secretion; the latter could be explained by serum binding.ConclusionsThe logP of a drug can aid prediction for its ability to block beta‐cell KATP ion channels. However, although the IC50 for the block of KATP by simvastatin was predicted, the difference between this and therapeutic levels, as well as serum sequestration, explains why hypoglycaemia is unlikely to be observed with acute use of this statin.
Peripherally induced regulatory T cells contribute to the control of autoimmune diabetes in the NOD mouse model
Authors: Schuster Cornelia , Jonas Franziska , Zhao Fangzhu , Kissler Stephan 
Published: March 2018

AbstractType 1 diabetes (T1D) results from the autoimmune destruction of pancreatic beta cells and is partly caused by deficiencies in the Foxp3+ regulatory T‐cell (Treg) compartment. Conversely, therapies that increase Treg function can prevent autoimmune diabetes in animal models. The majority of Tregs develop in the thymus (tTregs), but a proportion of Foxp3+ Tregs is generated in the periphery (pTregs) from Foxp3−CD4+ T‐cell precursors. Whether pTregs play a distinct role in T1D has not yet been explored. We report here that pTregs are a key modifier of disease in the nonobese diabetic (NOD) mouse model for T1D. We generated NOD mice deficient for the Foxp3 enhancer CNS1 involved in pTreg induction. We show that CNS1 knockout decreased the frequency of pTregs and increased the risk of diabetes. Our results show that pTregs fulfill an important non‐redundant function in the prevention of beta cell autoimmunity that causes T1D.
Design of Experiments Approach to Provide Enhanced Glucose‐oxidising Enzyme Electrode for Membrane‐less Enzymatic Fuel Cells Operating in Human Physiological Fluids
Authors: Bennett Richard , Osadebe Isioma , Kumar Rakesh , Conghaile Peter Ó , Leech Dónal 
Published: March 2018

AbstractGraphite electrodes are modified with a redox polymer, [Os(4,4′‐dimethoxy‐2,2′‐bipyridine)2(polyvinylimidazole)10Cl]+ (E°′=−0.02 V vs Ag/AgCl (3 M KCl), crosslinked with a flavin adenine dinucleotide glucose dehydrogenase and multi‐walled carbon nanotubes for electrocatalytic oxidation of glucose. The enzyme electrodes provide 52 % higher current density, 1.22±0.10 mA cm−2 in 50 mM phosphate‐buffered saline at 37 °C containing 5 mM glucose, when component amounts are optimised using a design of experiments approach compared to one‐factor‐at‐a‐time. Current densities of 0.84±0.15 mA cm−2 were achieved in the presence of oxygen for these enzyme electrodes. Further analysis of the model allowed for altering of the electrode components while maintaining similar current densities, 0.78±0.11 mA cm−2 with 34 % less enzyme. Application of the cost‐effective anodes in membrane‐less enzymatic fuel cells is demonstrated by connection to cathodes prepared by co‐immobilisation of [Os(2,2′‐bipyridine)2(polyvinylimidazole)10Cl+] redox polymer, Myrothecium verrucaria bilirubin oxidase and multi‐walled carbon nanotubes on graphite electrodes. Power densities of up to 285 μW cm−2, 146 μW cm−2 and 60 μW cm−2 are achieved in pseudo‐physiological buffer, artificial plasma and human plasma respectively, showing promise for in vivo or ex vivo power generation under these conditions.
Regional Differences in Dopamine Release in the R6/2 Mouse Caudate Putamen
Authors: Kaplan Sam V. , Limbocker Ryan A. , Levant Beth , Johnson Michael A. 
Published: March 2018

AbstractHuntington's disease (HD) is a fatal neurodegenerative disorder that is characterized by degeneration of the striatum. Here, fast‐scan cyclic voltammetry at carbon‐fiber microelectrodes was used to uncover regional differences in dopamine (DA) release in the caudate putamen of R6/2 and wild‐type control mice. We found a decreasing ventral‐to‐dorsal gradient in DA release, evoked by a single electrical stimulus pulse, in aged R6/2 mice. Moreover, under more intense stimulation conditions (120 pulses), DA release was significantly attenuated in the dorsal, but not in the ventral caudate. Autoradiography measurements using [3H] WIN 35,428 revealed that the overall density of DA transporter (DAT) protein molecules was significantly less in R6/2 mice compared to WT control mice; however, quadrants of the caudate putamen were not differentially altered in the R6/2 mice. These data collectively suggest that DA release in the dorsal caudate region is more vulnerable with age progression compared to the ventral region.