bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of bolaform biosurfactants by an engineered Starmerella bombicola yeast
Authors: Van Bogaert Inge N. A. , Buyst Dieter , Martins José C. , Roelants Sophie L. K. W. , Soetaert Wim K.
Published: June 2016

Bola‐amphiphilic surfactants are molecules with fascinating properties. Their unique configuration consisting of a long hydrophobic spacer connecting two hydrophilic entities renders the molecule more water soluble than the average surfactant, but still allows formation of supramolecular structures. These properties make them extremely suitable for applications in in nanotechnology, electronics, and gene and drug delivery. In general, these compounds are obtained by chemical synthesis. We report here an efficient microbial production process for the fully green synthesis of bolaform surfactants. A sophorolipid‐producing Starmerella bombicola yeast strain was disabled in its sophorolipid acetyltransferase and lactone esterase, which should logically result in synthesis of non‐acetylated acidic sophorolipids; molecules with the classic amphiphilic structure. Surprisingly, also bolaform glycolipids were obtained, with an additional sophorose linked to the free carboxyl end of the acidic sophorolipids as confirmed by MS and NMR analysis. The obtained titers of 27.7 g/L total product are comparable to wild type values, and the novel molecules account for at least 74% of this. Bola‐amphiphile biosynthesis proved to be attributed to the promiscuous activity of both UDP‐glucosyltransferases UGTA1 and UGTB1 from the core sophorolipid pathway, displaying activity toward non‐acetylated intermediates. The absence of acetyl groups seems to trigger formation of bolaform compounds starting from acidic sophorolipids. Hence, wild type S. bombicola produces these compounds only at marginal amounts in general not reaching detection limits. We created a strain knocked‐out in its sophorolipid acetyltransferase and lactone esterase able to produce these novel compounds in economical relevant amounts, opening doors for the application of biological‐derived bolaform structures. Biotechnol. Bioeng. 2016;113: 2644–2651. © 2016 Wiley Periodicals, Inc.
Combinatorial pathway optimization in Escherichia coli by directed co‐evolution of rate‐limiting enzymes and modular pathway engineering
Authors: Lv Xiaomei , Gu Jiali , Wang Fan , Xie Wenping , Liu Min , Ye Lidan , Yu Hongwei
Published: June 2016

Metabolic engineering of microorganisms for heterologous biosynthesis is a promising route to sustainable chemical production which attracts increasing research and industrial interest. However, the efficiency of microbial biosynthesis is often restricted by insufficient activity of pathway enzymes and unbalanced utilization of metabolic intermediates. This work presents a combinatorial strategy integrating modification of multiple rate‐limiting enzymes and modular pathway engineering to simultaneously improve intra‐ and inter‐pathway balance, which might be applicable for a range of products, using isoprene as an example product. For intra‐module engineering within the methylerythritol‐phosphate (MEP) pathway, directed co‐evolution of DXS/DXR/IDI was performed adopting a lycopene‐indicated high‐throughput screening method developed herein, leading to 60% improvement of isoprene production. In addition, inter‐module engineering between the upstream MEP pathway and the downstream isoprene‐forming pathway was conducted via promoter manipulation, which further increased isoprene production by 2.94‐fold compared to the recombinant strain with solely protein engineering and 4.7‐fold compared to the control strain containing wild‐type enzymes. These results demonstrated the potential of pathway optimization in isoprene overproduction as well as the effectiveness of combining metabolic regulation and protein engineering in improvement of microbial biosynthesis. Biotechnol. Bioeng. 2016;113: 2661–2669. © 2016 Wiley Periodicals, Inc.
Accurate measurement of poleward microtubule flux in the spindle of Drosophila S2 cells
Authors: Munzarova Alina , Popova Julia , Razuvaeva Alena , Shloma Victor , Gatti Maurizio , Omelyanchuk Leonid
Published: June 2016

The spindle microtubule (MT) flux is the continuous translocation of MTs toward the spindle poles caused by MT polymerization at plus ends coupled to depolymerization at minus ends. Poleward flux is observed in both mitotic and meiotic spindles; it is evolutionarily conserved and contributes to the regulation of spindle length and anaphase chromosome movement. MT photobleaching is a tool frequently used to measure poleward flux. Spindles containing fluorescently tagged tubulin are photobleached to generate a non‐fluorescent stripe, which moves toward the spindle poles allowing a measure of the flux. However, this method only permits rapid measurements of the flux, because the fluorescence of the bleached stripe recovers rapidly due to the spindle MT turnover. Here, we describe a modification of the current photobleaching‐based method for flux measurement. We photobleached two large areas at the opposite sides of the metaphase plate in spindles of Drosophila S2 cells expressing Cherry‐tagged tubulin, leaving unbleached only the area near the chromosomes. We then measured the speed with which the fluorescent MTs move toward the poles. We found that this method allows a measure of the flux over a two‐ to threefold longer time than the “single stripe” method, providing a reliable evaluation of the flux rate.
Lithium‐Rich Layered Oxide Li1.18Ni0.15Co0.15Mn0.52O2 as the Cathode Material for Hybrid Sodium‐Ion Batteries
Authors: Wei Zhixuan , Gao Yu , Wang Lei , Zhang Chaoyang , Bian Xiaofei , Fu Qiang , Wang Chunzhong , Wei Yingjin , Du Fei , Chen Gang
Published: June 2016

Li‐rich layered oxide Li1.18Ni0.15Co0.15Mn0.52O2 (LNCM) is, for the first time, examined as the positive electrode for hybrid sodium‐ion battery and its Na+ storage properties are comprehensively studied in terms of galvanostatic charge–discharge curves, cyclic voltammetry and rate capability. LNCM in the proposed sodium‐ion battery demonstrates good rate capability whose discharge capacity reaches about 90 mA h g−1 at 10 C rate and excellent cycle stability with specific capacity of about 105 mA h g−1 for 200 cycles at 5 C rate. Moreover, ex situ ICP‐OES suggests interesting mixed‐ions migration processes: In the initial two cycles, only Li+ can intercalate into the LNCM cathode, whereas both Li+ and Na+ work together as the electrochemical cycles increase. Also the structural evolution of LNCM is examined in terms of ex situ XRD pattern at the end of various charge–discharge scans. The strong insight obtained from this study could be beneficial to the design of new layered cathode materials for future rechargeable sodium‐ion batteries.
Saddle‐Shaped Cyclic Indole Tetramers: 3D Electroactive Molecules
Authors: Ruiz Constanza , Monge Ángeles , Gutiérrez‐Puebla Enrique , Alkorta Ibon , Elguero José , Navarrete Juan T. López , Ruiz Delgado M. Carmen , Gómez‐Lor Berta
Published: June 2016

We present a joint theoretical and experimental study of a series of cyclic indole tetramers aimed at understanding the fundamental electronic properties of this 3D platform and evaluating its potential in the construction of new semiconductors. To this end, we combined absorption and Raman spectroscopy, cyclic voltammetry, and spectroelectrochemistry with DFT calculations. Our results suggest that this platform can be easily and reversibly oxidized. Additionally, it has a HOMO that matches very well with the workfunction of gold, therefore charge injection from a gold electrode is expected to occur without significant barriers. Interestingly, the cyclic tetraindoles allow for good electron delocalization in spite of their saddle‐shaped structures. The steric constraints introduced by N‐substitution significantly inhibits ring inversion of the central cyclooctatetraene unit, whereas it only barely affects the optical and electrochemical properties (a slightly higher oxidation potential and a blueshifted absorption upon alkylation are observed).
Preparation and Properties of Transparent Ultrathin Lanthanide‐Complex Films
Authors: Li Yali , Xu Yang , Wang Yige
Published: June 2016

Highly transparent ultrathin films (UTFs) based on alternative layer‐by‐layer assembly of Eu‐ and Tb‐based lanthanide complexes (LCs) and Mg–Al‐layered double hydroxide (LDH) nanosheets are reported herein. UV–visible absorption and fluorescence spectroscopy showed an orderly growth of the two types of ultrathin films upon increasing the number of deposition cycles. AFM and SEM measurements indicate that the films feature periodic layered structures as well as uniform surface morphology. Luminescent investigations reveal that (LCs/LDH)n UTFs can detect Fe3+ with relative selectivity and high sensitivity (Stern–Volmer constant KSV=8.43×103 L mol−1); this suggests that (LCs/LDH)n UTFs could be a promising luminescent probe for selectively sensing Fe3+ ion.
Visible‐Light Photoredox‐Catalyzed Giese Reaction: Decarboxylative Addition of Amino Acid Derived α‐Amino Radicals to Electron‐Deficient Olefins
Authors: Millet Anthony , Lefebvre Quentin , Rueping Magnus
Published: June 2016

A tin‐ and halide‐free, visible‐light photoredox‐catalyzed Giese reaction was developed. Primary and secondary α‐amino radicals were generated readily from amino acids in the presence of catalytic amounts of an iridium photocatalyst. The reactivity of the α‐amino radicals has been evaluated for the functionalization of a variety of activated olefins.
Measuring Water Footprint on a Lake Basin Scale: A Case Study of Lake Dianchi, China
Authors: Hu Tingting , Huang Kai , Yu Yajuan , Zhang Xiaoxia , Xu Yanjie , Wang Xiaomeng
Published: June 2016

Water scarcity in lake basins has caused severe environmental problems. Water footprint assessment at the basin level is becoming a popular issue in water sustainability research. This study establishes a comprehensive water footprint assessment framework on the scale of a lake basin by using the top–down method. The components of water footprint assessment include agricultural water footprint, industrial water footprint, domestic water footprint, ecological environment water footprint, and virtual water flow, including virtual water imports and exports. This study used Lake Dianchi Basin in China as the case study area, based on published data, quantifying the total water footprint and measuring the water sustainability of Lake Dianchi Basin from 2000 to 2011. The results show that the average annual total water footprint for Lake Dianchi Basin was 28.18 × 108 m3, 95.4% of which was the internal water footprint. Agricultural production used most of the water, accounting for 74.1% of the total water footprint. The per capita water footprint was 960.51 m3/year, which was higher than those in most other regions of China. Lake Dianchi Basin should improve its water sustainability in terms of its internal and external water footprints. Importing water from other regions in both real and virtual forms should be considered in terms of the external water footprint. This study provides new insights on water footprint assessment methodology at the basin level and for improving basin water resource management from the macroscopic angle.
Use of cytology as an auxiliary diagnostic tool in autopsies
Authors: Andrade Luana , Massarente Vitória Lana , Tormin Stéphanie Corradini , Ribeiro Karina Braga , Pozzan Geanete , Saieg Mauro Ajaj
Published: June 2016

BACKGROUND

The use of minimally invasive procedures in autopsies such as image‐guided fine‐needle aspiration may facilitate family acceptance and, therefore, increase the number of postmortem examinations. The objective of the current study was to validate the use of cytology in a prospective set of conventional autopsies.

METHODS

All lesions and organs sampled for histological examination were concomitantly evaluated by scrape cytology of exactly the same location. The cytopathologist and the surgical pathologist were blinded to each other's microscopic findings. Final cytological and histological diagnoses were divided into 6 main diagnostic groups: normal, neoplasms (benign and malignant), inflammatory conditions, adaptive processes, degeneration, and cardiovascular disorders. Cytohistological agreement was assessed with Cohen's κ coefficient. The simple percentage agreement was also reported for each diagnostic group and for all different organs sampled in the postmortem examinations.

RESULTS

Two hundred eleven samples were studied from 36 consecutive autopsies (21 males and 15 females; median age, 58 years). Complete cytohistological agreement was achieved for 151 samples (71.6%) with a κ coefficient of 0.43 (moderate correlation). When samples were divided by diagnostic group, the best results were seen in normal specimens (93.8%) and neoplasms (82.3%). Organs with the best performance included the thyroid, cerebellum, lymph nodes, and adrenal glands (all with 100% agreement), the brain (90.5%), and the pancreas (84.6%).

CONCLUSIONS

Cytology showed a good correlation with histology, particularly for neoplastic cases and specimens with minimal pathological alterations, and could be used as an alternative diagnostic method in partial or restricted postmortem examinations. Cancer Cytopathol 2016;124:785‐90. © 2016 American Cancer Society.
Cytology as a diagnostic tool in the autopsy suite
Authors: Schnadig Vicki J.
Published: June 2016

Cytology is underused in the autopsy suite. Cytodiagnostic techniques can be used to improve autopsy quality and teaching and to limit organ removal when that is appropriate. See also pages 785‐90.
Data‐aware tuning of scientific applications with model‐based autotuning
Authors: Lang Jens
Published: June 2016

Autotuning is a widely accepted method for adapting the execution of scientific applications to the underlying hardware. One method for speeding up the search for the optimal candidate implementation in autotuning, which often is very time‐consuming, is the performance prediction using an analytical model. Using such a model‐based autotuning method, autotuning may be performed at runtime, which enables the application to consider data characteristics for the tuning decision. The article gives an overview on existing works, which apply model‐based autotuning for data‐aware tuning decisions in scientific computing. It shows that model‐based autotuning is a feasible method for increasing the performance of scientific applications by considering influences from the input data, where ‘performance’ may be execution time or energy, among others. It furthermore presents a systematisation of model‐based autotuning: it proposes a distinction of algorithm parameters, machine‐specific parameters and data‐specific parameters. The article gives suggestions on how to set up an application‐specific analytical model, presents an example for that and discusses the limits of model‐based autotuning. Copyright © 2016 John Wiley & Sons, Ltd.
Robust resource allocations through performance modeling with stochastic process algebra
Authors: Srivastava Srishti , Banicescu Ioana
Published: June 2016

Parallel and distributed computing has led to a proliferation in solving computationally intensive mathematical, science, or engineering problems. However, such computational environments are often prone to unpredictable variations due to problem, algorithm, and system characteristics. Therefore, a robustness study of resource allocations and application scheduling is required to guarantee a desired level of performance. Given an initial workload, a mapping of applications to resources is considered to be robust if it optimizes the execution performance and guarantees a desired level of performance in the presence of unpredictable perturbations at runtime. In this research work, a stochastic process algebra, performance evaluation process algebra, is used for obtaining performance of various resource allocations via a numerical analysis of performance modeling of the parallel execution of applications on parallel computing resources. Further, a robustness analysis of various allocations is performed for finding a robust mapping from a set of initial mapping schemes. The numerical results obtained from this performance modeling of resource allocations have been validated by the simulation results of earlier research, which are available from the existing literature, thus underscoring the significance of using stochastic process algebra models in providing a cost‐effective and low overhead analysis of robustness. Copyright © 2016 John Wiley & Sons, Ltd.
A DFT Study on the Co‐polymerization of CO2 and Ethylene: Feasibility Analysis for the Direct Synthesis of Polyethylene Esters
Authors: Moha Verena , Cozzula Daniela , Hölscher Markus , Leitner Walter , Müller Thomas E.
Published: June 2016

The co‐polymerization of CO2 with the non‐polar monomer ethylene, though highly desirable, still presents a challenge whereas the palladium‐catalyzed CO/C2H4 co‐polymerization is well understood. Building on this analogy, the goal of this study was to elucidate the feasibility of developing suitable catalysts for co‐polymerizing CO2 with ethylene to polyethylene esters. Computational methods based on density functional theory were hereby employed. In the search for new catalyst lead structures, a closed catalytic cycle was identified for the palladium‐catalyzed CO2/C2H4 co‐polymerization reaction. The computational study on palladium complexes with a substituted anionic 2‐[bis(2,4‐dimethoxyphenyl)‐phosphine]‐benzene‐2‐hydroxo ligand revealed key aspects that need to be considered when designing ligand sets for potential catalysts for the non‐alternating co‐polymerization of CO2 and ethylene.
Synthesis of Industrially Relevant Carbamates towards Isocyanates using Carbon Dioxide and Organotin(IV) Alkoxides
Authors: Germain Nicolas , Müller Imke , Hanauer Matthias , Paciello Rocco A. , Baumann Robert , Trapp Oliver , Schaub Thomas
Published: June 2016

A straightforward phosgene‐free synthesis of aromatic isocyanates and diisocyanates is disclosed. Theoretical investigations suggested that the insertion of carbon dioxide (CO2) by dialkyltin(IV) dialkoxides could be used to convert aromatic amines into aromatic mono‐ and dicarbamates. Here we show, that methyl phenylcarbamate (MPC) from aniline using organotin(IV) dimethoxide and CO2 can be formed in high yield of up to 92 %, experimentally corroborating the predictions of density functional theory (DFT) calculations. MPC was then separated from the tin oxide residues and converted into phenyl isocyanate. Furthermore, organotin(IV) alkoxides could be regenerated from the tin oxide residues and reused, paving the way for a continuous industrial process. Extension of the scope to the synthesis of diurethanes from toluene 2,4‐diamine and 4,4′‐methylenedianiline could potentially allow the efficient production of industrially relevant diisocyanates.
Can you hear me now? Range‐testing a submerged passive acoustic receiver array in a Caribbean coral reef habitat
Authors: Selby Thomas H. , Hart Kristen M. , Fujisaki Ikuko , Smith Brian J. , Pollock Clayton J. , Hillis‐Starr Zandy , Lundgren Ian , Oli Madan K.
Published: June 2016

Submerged passive acoustic technology allows researchers to investigate spatial and temporal movement patterns of many marine and freshwater species. The technology uses receivers to detect and record acoustic transmissions emitted from tags attached to an individual. Acoustic signal strength naturally attenuates over distance, but numerous environmental variables also affect the probability a tag is detected. Knowledge of receiver range is crucial for designing acoustic arrays and analyzing telemetry data. Here, we present a method for testing a relatively large‐scale receiver array in a dynamic Caribbean coastal environment intended for long‐term monitoring of multiple species. The U.S. Geological Survey and several academic institutions in collaboration with resource management at Buck Island Reef National Monument (BIRNM), off the coast of St. Croix, recently deployed a 52 passive acoustic receiver array. We targeted 19 array‐representative receivers for range‐testing by submersing fixed delay interval range‐testing tags at various distance intervals in each cardinal direction from a receiver for a minimum of an hour. Using a generalized linear mixed model (GLMM), we estimated the probability of detection across the array and assessed the effect of water depth, habitat, wind, temperature, and time of day on the probability of detection. The predicted probability of detection across the entire array at 100 m distance from a receiver was 58.2% (95% CI: 44.0–73.0%) and dropped to 26.0% (95% CI: 11.4–39.3%) 200 m from a receiver indicating a somewhat constrained effective detection range. Detection probability varied across habitat classes with the greatest effective detection range occurring in homogenous sand substrate and the smallest in high rugosity reef. Predicted probability of detection across BIRNM highlights potential gaps in coverage using the current array as well as limitations of passive acoustic technology within a complex coral reef environment.
Estimating species – area relationships by modeling abundance and frequency subject to incomplete sampling
Authors: Yamaura Yuichi , Connor Edward F. , Royle J. Andrew , Itoh Katsuo , Sato Kiyoshi , Taki Hisatomo , Mishima Yoshio
Published: June 2016

Models and data used to describe species–area relationships confound sampling with ecological process as they fail to acknowledge that estimates of species richness arise due to sampling. This compromises our ability to make ecological inferences from and about species–area relationships. We develop and illustrate hierarchical community models of abundance and frequency to estimate species richness. The models we propose separate sampling from ecological processes by explicitly accounting for the fact that sampled patches are seldom completely covered by sampling plots and that individuals present in the sampling plots are imperfectly detected. We propose a multispecies abundance model in which community assembly is treated as the summation of an ensemble of species‐level Poisson processes and estimate patch‐level species richness as a derived parameter. We use sampling process models appropriate for specific survey methods. We propose a multispecies frequency model that treats the number of plots in which a species occurs as a binomial process. We illustrate these models using data collected in surveys of early‐successional bird species and plants in young forest plantation patches. Results indicate that only mature forest plant species deviated from the constant density hypothesis, but the null model suggested that the deviations were too small to alter the form of species–area relationships. Nevertheless, results from simulations clearly show that the aggregate pattern of individual species density–area relationships and occurrence probability–area relationships can alter the form of species–area relationships. The plant community model estimated that only half of the species present in the regional species pool were encountered during the survey. The modeling framework we propose explicitly accounts for sampling processes so that ecological processes can be examined free of sampling artefacts. Our modeling approach is extensible and could be applied to a variety of study designs and allows the inclusion of additional environmental covariates.
Effect of Axial Slit on Metallic Tube for Wireless Power Transfer via Magnetic Resonance Coupling
Authors: SHIMAMURA KOHEI , KOIZUMI MASAYOSHI , MIZUNO YOSHIHIRO , KOMURASAKI KIMIYA
Published: June 2016

Wireless power transfer using a metallic tube with an axial slit was attempted to demonstrate the wireless power transfer using magnetic resonance coupling to the diagnostics infrastructure. The transmission efficiency with variable distance was measured using the transmission and receiver resonators in the tube. Besides, the transmission and receiver resonators were, respectively, set outside and inside the tube. These experiments are carried out in the computational study using FDTD method.
Ligand Noninnocence in Silver Corroles: A XANES Investigation
Authors: Sarangi Ritimukta , Giles Logan J. , Thomas Kolle E. , Ghosh Abhik
Published: June 2016

Structural, optical spectroscopy, and DFT studies have recently suggested a remarkable electronic–structural switch between simple silver meso‐triarylcorroles and silver β‐octabromo‐meso‐triarylcorroles: the former were described as essentially innocent and the latter as substantially noninnocent. In a first X‐ray absorption near‐edge spectroscopic (XANES) study of ligand noninnocence in metallocorroles, Ag L3‐edge spectra have now provided direct experimental support for the variable electronic structure of silver corroles.
Rapid detection and separation of olive oil and Camellia oil based on ion mobility spectrometry fingerprints and chemometric models
Authors: Liu Lingyi , Hu Chuanrong , Liu Lianliang , Zhang Sihong , Chen Ke , He Dongping
Published: June 2016

A simple and rapid classification model for olive and Camellia oil was proposed based on ion mobility spectrometry (IMS) fingerprints and chemometric model (peak detection and random forest algorithm). Results indicated that IMS fingerprint spectra by second‐derivative algorithm could completely separate 64 olive oil and 79 Camellia oil samples used in this study by simply calculating the peak area. Random forest algorithm was employed to establish discriminant model for olive oil adulterated by Camellia oil. Simulated adulteration detection showed that the accuracy rate of discriminant model is 96.4% as two of 55 samples were identified as blending olive oil. All these results suggested that IMS could be an effective method to detect the adulterated olive oils by Camellia oil.

Practical applications: Camellia oil is much similar to olive oil no matter in the physicochemical properties and fatty acid profiles. Thereby, olive oil has been one of the most frequent targets for the adulteration by Camellia oil. This study aimed to provide a rapid method to detect and separate olive oil and Camellia oil by a portable IMS device, by using fingerprints spectra, peak detection (first‐ and second‐derivative algorithm), and random forest algorithm. Results indicated that the classification and discriminant model established in this work was doable for the adulteration detection in the industry.

Based on fingerprints spectra, peak detection (first‐ and second‐derivative algorithm) and random forest algorithm, IMS detection is doable for the rapid detection and separation of olive and Camellia oil.
Unexpected Hydration of a Triple Bond During DNA Synthesis: Conjugating 3‐(Pyren‐1‐ylethynyl)indole to DNA for Triplex Studies
Authors: Fatthalla Maha I. , Pedersen Erik B.
Published: June 2016

Twisted intercalating nucleic acid (TINA) has the ability to stabilize Hoogsteen triplex formation. New oligonucleotides containing 3‐(pyren‐1‐ylethynyl)indole as a DNA linked intercalator backbone have been added to the TINA family and their synthetic route has been devised. The indole ring, under acidic conditions, polarizes the triple bond in the intercalator and this makes hydration of the triple bond possible during the DNA synthesis and an oligonucleotide with 1‐(indol‐3‐yl)‐2‐(pyren‐1‐yl)ethanone as the intercalator is formed. Insertion of the unhydrated and hydrated linker systems gave characteristic UV spectra comparable to its monomeric diols due to π‐conjugated and isolated pyrene systems, respectively. Thermal denaturation profile at pH 6–7.2 showed excellent stabilization of the triplex upon insertion of 3‐(pyren‐1‐ylethynyl)indole when compared to wild‐type triplexes. The investigation includes fluorescence spectroscopic and molecular modeling studies.
Hydrogen Bonded Phenol‐Quinolines with Highly Controlled Proton‐Transfer Coordinate
Authors: Parada Giovanny A. , Glover Starla D. , Orthaber Andreas , Hammarström Leif , Ott Sascha
Published: June 2016

A series of polycyclic phenols with intramolecular hydrogen bonds (IMHB) to quinolines was synthesized by Friedländer annulation of cycloalkanone‐functionalized anisoles with 2‐aminobenzaldehyde. The prepared compounds represent the first series of IMHB phenols in which the substitution and conjugation patterns between the phenols and the hydrogen bond acceptors are kept constant, and in which comparable electronic interaction between the two subunits is thus ensured. The distance and relative orientation between the phenolic OH and the quinolone nitrogen atom is controlled by 1,3‐cycloalkadienes of different ring sizes to which the phenol and quinoline subunits are formally annulated. 1H δ(OH) chemical shift and X‐ray crystal structure characterization support the conclusion that the size and conformational preference of the 1,3‐cycloalkadiene rings control the H‐bond geometry and strength. As a result, the oxygen to nitrogen distances differ by as much as 0.30 Å across the series.
Intermolecular Electrophilic Addition of Epoxides to Alkenes: [3+2] Cycloadditions Catalyzed by Lewis Acids
Authors: Shuler William G. , Combee Logan A. , Falk Isaac D. , Hilinski Michael K.
Published: June 2016

Described are the first examples of intermolecular electrophilic additions of epoxides to alkenes, which proceed through a classic cationic mechanism initiated by epoxide C–O bond cleavage. Treatment of styrene oxides and either styrenes or dienes with a variety of Lewis‐acidic triflate salts generates tetrahydrofurans as products of [3+2] cycloaddition in moderate to good yields (up to 71 %). Careful choice of catalyst and reaction conditions favors the desired intermolecular reaction over epoxide degradation without requiring additional reagents or additives. The reaction proceeds diastereoselectively and provides only one regioisomer of the product. Additional highlights include inexpensive precursors, mild conditions, short reaction times, low catalyst loading, and scalability.
Scanning Electrochemical Microscopy for the In Situ Characterization of Solid–Electrolyte Interphases: Highly Oriented Pyrolytic Graphite versus Graphite Composite
Authors: Bülter Heinz , Peters Fabian , Wittstock Gunther
Published: June 2016

The solid–electrolyte interphase (SEI) is of key importance for the performance and safety of lithium‐ion batteries. Recently, scanning electrochemical microscopy (SECM) has been used to study in situ the SEI. Here, we compare the SEI of graphite composite electrodes to the SEI at macroscopic samples of binder‐free, highly oriented pyrolytic graphite (HOPG) where effects of mechanical processing and particle–particle as well as electrolyte–binder interactions should be absent. Both, short‐term changes of SEI passivity on the timescale of seconds and minutes and long‐term changes over hours are found on HOPG as well as on graphite composite electrodes, but the SEI at HOPG is more stable compared to graphite composite electrodes. In addition, the microelectrode probe of the SECM is used to induce local SEI damage to monitor its reformation. Subsequently, secondary processes such as local crack formation, gas formation due to electrolyte reduction, and HOPG expansion are studied.
Direct Local Mapping of Ion Transfer Reactions by Scanning Ohmic Microscopy
Authors: Plettenberg Inka , Wittstock Gunther
Published: June 2016

Scanning ohmic microscopy (SOM) detects a current by the potential difference along the current line. Using two microreference electrodes (MREs) and a very close distance to the electrode surface of interest, this principle can be used to record local current densities independently of the reaction that causes the current flow (ion or electron transfer processes). Ion transfer processes are difficult to image by scanning electrochemical microscopy (SECM). Here we present technical details of our SOM setup with possible extension required for the analysis of battery materials. In this respect, the selection of the specific voltage probes is explored for different applications. Our concept further uses voltage programs, for example, cyclic voltammetry, at each grid point of the image and the integration of specific voltage ranges to obtain material‐specific signals, and is extended by the use of a shear‐force detection unit at inclined capillaries for topographical imaging and an accurate vertical positioning of the probe.
Lower Prices, More Renewables, Net Metering in Today's Electrics
Authors:   FERC Staff
Published: June 2016

The year 2015 was eventful in the energy markets, as oil and natural gas prices fell substantially due to surging supply and strong storage builds. Low gas prices resulted in natural gas generation surpassing coal generation for seven months during 2015. Due to low natural gas prices, for the first time in US history, natural gas power generation surpassed coal‐based generation on both a quarterly and monthly basis. Summer temperatures were 8 percent warmer than in 2014, but the 2015–16 winter was relatively mild due to El Niño, which moderated residential and commercial demand at the end of the year.
Reliable, resilient and sustainable water management: the Safe & SuRe approach
Authors: Butler David , Ward Sarah , Sweetapple Chris , Astaraie‐Imani Maryam , Diao Kegong , Farmani Raziyeh , Fu Guangtao
Published: June 2016

Global threats such as climate change, population growth, and rapid urbanization pose a huge future challenge to water management, and, to ensure the ongoing reliability, resilience and sustainability of service provision, a paradigm shift is required. This paper presents an overarching framework that supports the development of strategies for reliable provision of services while explicitly addressing the need for greater resilience to emerging threats, leading to more sustainable solutions. The framework logically relates global threats, the water system (in its broadest sense), impacts on system performance, and social, economic, and environmental consequences. It identifies multiple opportunities for intervention, illustrating how mitigation, adaptation, coping, and learning each address different elements of the framework. This provides greater clarity to decision makers and will enable better informed choices to be made. The framework facilitates four types of analysis and evaluation to support the development of reliable, resilient, and sustainable solutions: “top‐down,” “bottom‐up,” “middle based,” and “circular” and provides a clear, visual representation of how/when each may be used. In particular, the potential benefits of a middle‐based analysis, which focuses on system failure modes and their impacts and enables the effects of unknown threats to be accounted for, are highlighted. The disparate themes of reliability, resilience and sustainability are also logically integrated and their relationships explored in terms of properties and performance. Although these latter two terms are often conflated in resilience and sustainability metrics, the argument is made in this work that the performance of a reliable, resilient, or sustainable system must be distinguished from the properties that enable this performance to be achieved.
A Clustered Multiclass Likelihood‐Ratio Ensemble Method for Family‐Based Association Analysis Accounting for Phenotypic Heterogeneity
Authors: Wen Yalu , Lu Qing
Published: June 2016

Although compelling evidence suggests that the genetic etiology of complex diseases could be heterogeneous in subphenotype groups, little attention has been paid to phenotypic heterogeneity in genetic association analysis of complex diseases. Simply ignoring phenotypic heterogeneity in association analysis could result in attenuated estimates of genetic effects and low power of association tests if subphenotypes with similar clinical manifestations have heterogeneous underlying genetic etiologies. To facilitate the family‐based association analysis allowing for phenotypic heterogeneity, we propose a clustered multiclass likelihood‐ratio ensemble (CMLRE) method. The proposed method provides an alternative way to model the complex relationship between disease outcomes and genetic variants. It allows for heterogeneous genetic causes of disease subphenotypes and can be applied to various pedigree structures. Through simulations, we found CMLRE outperformed the commonly adopted strategies in a variety of underlying disease scenarios. We further applied CMLRE to a family‐based dataset from the International Consortium to Identify Genes and Interactions Controlling Oral Clefts (ICOC) to investigate the genetic variants and interactions predisposing to subphenotypes of oral clefts. The analysis suggested that two subphenotypes, nonsyndromic cleft lip without palate (CL) and cleft lip with palate (CLP), shared similar genetic etiologies, while cleft palate only (CP) had its own genetic mechanism. The analysis further revealed that rs10863790 (IRF6), rs7017252 (8q24), and rs7078160 (VAX1) were jointly associated with CL/CLP, while rs7969932 (TBK1), rs227731 (17q22), and rs2141765 (TBK1) jointly contributed to CP.
Rapid Prototyping in Humanitarian Aid To Manufacture Last Mile Vehicles Spare Parts: An Implementation Plan
Authors: De la Torre N. , Espinosa M. M. , Domínguez M.
Published: June 2016

This research examines the use of rapid prototyping technologies in the supply chain of spare parts. Spare parts are manufactured in small production lots and distributed in wide areas, eventually requiring short delivery times. The focus of this research is the use of rapid prototyping in humanitarian logistics. The demand of humanitarian aid is large, but it is very difficult to predict and also to supply. The use of rapid prototyping to produce spare parts can greatly increase the availability of scarce resources. In this paper, it is demonstrated that rapid prototyping of spare parts for last mile vehicles can help achieve a cost‐effective solution to increase vehicle availability. Also, a detailed implementation plan is developed to serve as a guideline for any organization to successfully introduce the equipment in their operations.
Combretins A and B, New Cycloartane‐Type Triterpenes from Combretum fragrans
Authors: Dawe Amadou , Kapche Gilbert Deccaux Wabo Fotso , Bankeu Jean Jules Kezetas , Fawai Yakai , Ali Muhammad Shaiq , Ngadjui Bonaventure Tchaleu
Published: June 2016

The phytochemical studies on the leaves of the traditionally used medicinal plant Combretum fragrans F. Hoffm (Combretaceae) from Cameroon have led to the isolation of combretins A and B (1 and 2, resp.), two new cycloartane‐type triterpenes from the AcOEt‐soluble subfraction along with β‐sitosterol (3), oleanolic acid (4), ursolic acid (5), and pratensein (6). The compounds 4 – 6 are reported for the first time from this species. The structures of the new triterpenes were elucidated by spectroscopic techniques including 1H‐ and 13C‐NMR (DEPT), and 2D‐NMR experiments.
Exploring the effects of low‐level laser therapy on fibroblasts and tumor cells following gamma radiation exposure
Authors: Ramos Silva Camila , Cabral Fernanda Viana , de Camargo Claudinei Francisco Morais , Núñez Silvia Cristina , Mateus Yoshimura Tania , de Lima Luna Arthur Cássio , Maria Durvanei Augusto , Ribeiro Martha Simões
Published: June 2016

Ionizing radiation (IR) induces DNA damage and low‐level laser therapy (LLLT) has been investigated to prevent or repair detrimental outcomes resulting from IR exposure. Few in vitro studies, however, explore the biological mechanisms underlying those LLLT benefits. Thus, in this work, fibroblasts and tumor cells are submitted to IR with doses of 2.5 Gy and 10 Gy. After twenty‐four‐h, the cells are exposed to LLLT with fluences of 30 J cm–2, 90 J cm–2, and 150 J cm–2. Cellular viability, cell cycle phases, cell proliferation index and senescence are evaluated on days 1 and 4 after LLLT irradiation. For fibroblasts, LLLT promotes – in a fluence‐dependent manner – increments in cell viability and proliferation, while a reduction in the senescence was observed. Regarding tumor cells, no influences of LLLT on cell viability are noticed. Whereas LLLT enhances cell populations in S and G2/M cell cycle phases for both cellular lines, a decrease in proliferation and increase in senescence was verified only for tumor cells. Putting together, the results suggest that fibroblasts and tumor cells present different responses to LLLT following exposure to gamma‐radiation, and these promising results should stimulate further investigations.

Senescence of tumor cells and fibroblasts on the 4th day after ionizing radiation (IR) and low‐level laser therapy (LLLT) exposures. The number of senescent cells increased significantly for tumor cells (a) while for fibroblasts no increment was observed (b). The blue collor indicates senescence activity.

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Senescence of tumor cells and fibroblasts on the 4th day after ionizing radiation (IR) and low‐level laser therapy (LLLT) exposures. The number of senescent cells increased significantly for tumor cells (a) while for fibroblasts no increment was observed (b). The blue collor indicates senescence activity.
Links Between the Microbiome and Bone
Authors: Hernandez Christopher J , Guss Jason D , Luna Marysol , Goldring Steven R
Published: June 2016

The human microbiome has been shown to influence a number of chronic conditions associated with impaired bone mass and bone quality, including obesity, diabetes, and inflammatory bowel disease. The connection between the microbiome and bone health, however, has not been well studied. The few studies available demonstrate that the microbiome can have a large effect on bone remodeling and bone mass. The gut microbiome is the largest reservoir of microbial organisms in the body and consists of more than a thousand different species interacting with one another in a stable, dynamic equilibrium. How the microbiome can affect organs distant from the gut is not well understood but is believed to occur through regulation of nutrition, regulation of the immune system, and/or translocation of bacterial products across the gut endothelial barrier. Here we review each of these mechanisms and discuss their potential effect on bone remodeling and bone mass. We discuss how preclinical studies of bone-microbiome interactions are challenging because the microbiome is sensitive to genetic background, housing environment, and vendor source. Additionally, although the microbiome exhibits a robust response to external stimuli, it rapidly returns to its original steady state after a disturbance, making it difficult to sustain controlled changes in the microbiome over time periods required to detect alterations in bone remodeling, mass, or structure. Despite these challenges, an understanding of the mechanisms by which the gut microbiome affects bone has the potential to provide insights into the dissociation between fracture risk and bone mineral density in patients including those with obesity, diabetes, or inflammatory bowel disease. In addition, alteration of the gut microbiome has the potential to serve as a biomarker of bone metabolic activity as well as a target for therapies to improve bone structure and quality using pharmaceutical agents or pre- or probiotics. © 2016 American Society for Bone and Mineral Research.
A critical assessment of hidden markov model sub‐optimal sampling strategies applied to the generation of peptide 3D models
Authors: Lamiable A. , Thevenet P. , Tufféry P.
Published: June 2016

Hidden Markov Model derived structural alphabets are a probabilistic framework in which the complete conformational space of a peptidic chain is described in terms of probability distributions that can be sampled to identify conformations of largest probabilities. Here, we assess how three strategies to sample sub‐optimal conformations—Viterbi k‐best, forward backtrack and a taboo sampling approach—can lead to the efficient generation of peptide conformations. We show that the diversity of sampling is essential to compensate biases introduced in the estimates of the probabilities, and we find that only the forward backtrack and a taboo sampling strategies can efficiently generate native or near‐native models. Finally, we also find such approaches are as efficient as former protocols, while being one order of magnitude faster, opening the door to the large scale de novo modeling of peptides and mini‐proteins. © 2016 Wiley Periodicals, Inc.
Efficient determination of accurate atomic polarizabilities for polarizeable embedding calculations
Authors: Schröder Heiner , Schwabe Tobias
Published: June 2016

We evaluate embedding potentials, obtained via various methods, used for polarizable embedding computations of excitation energies of para‐nitroaniline in water and organic solvents as well as of the green fluorescent protein. We found that isotropic polarizabilities derived from DFTD3 dispersion coefficients correlate well with those obtained via the LoProp method. We show that these polarizabilities in conjunction with appropriately derived point charges are in good agreement with calculations employing static multipole moments up to quadrupoles and anisotropic polarizabilities for both computed systems. The (partial) use of these easily‐accessible parameters drastically reduces the computational effort to obtain accurate embedding potentials especially for proteins. © 2016 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc.
CarbBuilder: Software for building molecular models of complex oligo‐ and polysaccharide structures
Authors: Kuttel Michelle M. , Ståhle Jonas , Widmalm Göran
Published: June 2016

CarbBuilder is a portable software tool for producing three‐dimensional molecular models of carbohydrates from the simple text specification of a primary structure. CarbBuilder can generate a wide variety of carbohydrate structures, ranging from monosaccharides to large, branched polysaccharides. Version 2.0 of the software, described in this article, supports monosaccharides of both mammalian and bacterial origin and a range of substituents for derivatization of individual sugar residues. This improved version has a sophisticated building algorithm to explore the range of possible conformations for a specified carbohydrate molecule. Illustrative examples of models of complex polysaccharides produced by CarbBuilder demonstrate the capabilities of the software. CarbBuilder is freely available under the Artistic License 2.0 from https://people.cs.uct.ac.za/~mkuttel/Downloads.html. © 2016 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc.
Green and Efficient Synthesis of 4‐Heteryl‐Quinolines and Their Antibacterial Evaluations
Authors: Bhupathi Raja S. , Bandi Madhu , Ch. Venkata Ramana Reddy , Rama Devi B. , Dubey P.K.
Published: June 2016

A green and efficient synthesis of 4‐heteryl‐quinolines (9a, 9b, 9c, 9d), (10a, 10b, 10c, 10d) and (11a, 11b, 11c, 11d) has been described using PEG‐600 as a green solvent. Initially, 4‐chloro‐2‐methylquinolines (5a, 5b, 5c, 5d) on reaction with aromatic heterocyclic thiols (6), (7), and (8) using PEG‐600 at 100°C for 30–40 min resulted in (9), (10), and (11) in good yields. Alternatively, (9), (10), and (11) could also be prepared in dimethylformamide using K2CO3 as base and tetrabutylammonium bromide as phase transfer catalyst at 100°C for 1–2 h. All the compounds were synthesized and characterized by IR, NMR, mass spectroscopy, and 13C NMR analysis. All synthesized compounds were screened for their antibacterial activity against clinical strains that include Gram‐positive (Bacillus subtilis MTCC 121, staphylococcus aureus MLS‐16 MTCC 2940, Micrococcus lutes MTCC 2470, and Staphylococcus aureus MTCC 96) and Gram‐negative bacteria (Candida albicans MTCC 3017, Klebsiella planticola MTCC 530, Escherichia coli MTCC 739, and Pseudomonas aeruginosa MTCC 2453). The results revealed that compounds (9a, 9d, 10a, 10c, 11b, and 11d) exhibited significant antibacterial activity almost equal to the standard drug, that is, Ciprofloxacin.