bluuebunny/crossref_metadata_2025 huggingface dataset:
Surfactant‐Induced Preparation of Highly Dispersed Ni‐Nanoparticles Supported on Nanocrystalline ZrO2for Chemoselective Reduction of Nitroarenes
Authors: Shukla Astha , Singha Rajib K. , Sengupta Manideepa , Sasaki Takehiko , Pendem Chandrashekar , Bal Rajaram
Published: January 2018

Metal‐support interaction plays crucial role in heterogeneous catalysis, stabilizing the active metal species during catalysis. We report here the successful preparation of highly dispersed nickel nanoparticles supported ZrO2nanocrystals, which showed excellent performance toward catalytic reduction of nitroarenes to their corresponding amines, where metal‐support interaction plays the key role in enhancing the activity and stability of catalyst. The catalyst was synthesized by a single step hydrothermal method using CTAB (cetyltrimethyl ammonium bromide) as a structure‐ directing agent and PVP (Polyvinylpyrrolidone) as capping agent. Prepared catalyst was characterized by BET‐surface area, Inductively coupled plasma atomic emission spectroscopy (ICP‐AES), X‐ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Temperature programmed reduction (TPR), X‐ray photoelectron spectroscopy (XPS), Fourier transform infra‐red (FT‐IR) spectroscopy, RAMAN spectroscopy, Thermogravimetric analysis (TGA‐DTA), UV‐vis spectroscopy and Extended X‐ray absorption fine structure (EXAFS) analysis. Results obtained from XRD and TPR analysis of 4.9% Ni‐ZrO2, support the presence of highly dispersed and subtle Ni (below 5 nm) nanoparticles supported on nanocrystalline ZrO2. Prepared 4.9 wt% Ni‐ZrO2catalyst showed 100% conversion ofp‐nitrophenol with >99% selectivity top‐aminophenol in aqueous medium at 60 °C, in presence of molecular H2(1.0 MPa). Superior activity of 4.9% Ni‐ZrO2was due to presence of very small (below 5 nm), uniformly distributed, highly dispersed nickel nanoparticle having good metal‐support interaction. Prepared 4.9% Ni‐ZrO2catalyst was recycled up to eight successive runs without any significant loss in catalytic activity.
Timescale of π‐Stacking Formation in a Benzene Trimer Cation Formed by Ionization of the Parent Neutral Trimer: A Direct Ab Initio Molecular Dynamics Study
Authors: TACHIKAWA Hiroto , MIYAZAWA Yoshiyuki , IURA Ryoshu
Published: January 2018

The π‐stacking interaction plays a crucial role in structural arrangements and molecular assemblies in several molecular systems. In the present study, π‐stacking formation in the benzene trimer cation, (Bz)3+, following ionization of the parent neutral benzene trimer, (Bz)3, was investigated using direct ab initio molecular dynamics to elucidate the timescale of π‐stacking formation and reaction mechanism in the ionized state. Cyclic (Bz)3 was chosen as the benzene cluster. After ionizing (Bz)3, the structure drastically changed to a double π‐stacking form. The (Bz)3+ product vibrated between two structural forms, (Bz‐Bzc)+—Bz ↔ Bz—(Bzc‐Bz)+, where Bzc is a benzene molecule located in the central position of (Bz)3+ and (Bzc‐Bz)+ represents a dimer core composed of the benzene dimer cation. The timescale of π‐stacking formation was calculated as 300–380 fs. The absorption spectrum of (Bz)3+ was blue‐shifted as a function of time. We discuss the reaction mechanism based on the theoretical results.
Synthesis of β‐Amino Alcohols Using Ethyl 2‐Cyano‐2‐(2‐nitrobenzenesulfonyloxyimino)acetate (o‐NosylOXY)
Authors: Manne Srinivasa Rao , Chandra Jyoti , Giri Rajat Subhra , Kalita Tapasi , Mandal Bhubaneswar
Published: January 2018

We describe a mild and efficient method for the direct synthesis of β‐amino alcohols from N‐protected amino acids using ethyl‐2‐cyano‐2‐(2‐nitrophenylsulfonyloxyimino)acetate (ortho‐NosylOXY). The reaction sequence includes activation of carboxylic acid, followed by reduction with sodium borohydride, resulting in β‐amino alcohols in good yields. This method is compatible with various N‐protecting groups as well as the side chain protecting groups of amino acids. The excellent racemization suppression capability and recyclable nature of ortho‐NosylOXY is an added feature to the in‐situ activation mediated carboxylic acid reduction.
Engineered Carbon Nanotubes: Review on the Role of Surface Chemistry, Mechanistic Features, and Toxicology in the Adsorptive Removal of Aquatic Pollutants.
Authors: Mishra Nirmalendu S. , Kuila Aneek , Nawaz Ahmad , Pichiah Saravanan , Leong Kah Hon , Jang Min
Published: January 2018

The advent of nanotechnology has led to the development of new nanomaterials with enriched material properties over the conventional. These nanomaterials find wide application in numerous fields including environmental predominantly on water purification. Carbon nanotubes (CNT) are one among the nanomaterials widely employed for such application. Therefore, the present review emphasizes on the exceptional abilities of CNT especially in the removal of organics and inorganics from aquatic streams. Though numerous reviews were published in this subject most of them focused on the synthesis and specific applications. The authors learned that there is a wider gap on the review that presents the mechanistic features like the development of active sites, the effect of curvature, inclusion of heteroatoms, methods for the enhancement of affinity and selectivity through functionalization, the introduction of defects and the chemistry involved in their interaction with various category of pollutants. Hence, the present review delivers a clear understanding of the above‐said factors in a comprehensive way. The article explicits on the various surface modification techniques (i.e covalent, non‐covalent, defect and endohedral) along with their effects on the sorption efficiency. Further, the review also provides a clear picture of the toxicological aspects of the CNT. The authors strongly believe that the present review will aid in the understanding and design of multifunctional CNT towards environmental application in a comprehensive manner.
Synthesis, Characterization and Catalytic Activity of Quadruple Perovskite: CaCu3‐xMnxTi4‐xMnxO12 (x=0, 0.5 and 1.0)
Authors: Pal Kamalesh , Dey Arka , Ray Partha P. , Mordvinova Natalia E. , Lebedev Oleg I. , Mandal Tapas K. , Seikh Md Motin , Gayen Arup
Published: January 2018

We report the low temperature synthesis of nanosized CaCu3‐xMnxTi4‐xMnxO12 (x= 0, 0.5 and 1.0) quadruple perovskites and their magnetic, dielectric and catalytic performance towards CO oxidation and methanol steam reforming (MSR). Our investigations reveal the pronounced effects of particle size and chemical substitution on all the physical properties reported here. The manganese doped samples exhibit remarkable change in magnetic properties, where antiferromagnetic pristine phase converted to ferrimagnetic phase for x=1. The dielectric constant values of the cold‐pressed nanosized perovskites are ∼103 and follows Maxwell‐Wagner type relaxation. This value is about 100 fold lower than that of the bulk samples that has been ascribed to the effect of particle size and the absence of nano‐twinning in the material as revealed from HRTEM studies. The doping of manganese further reduces the magnitude of dielectric value, which is the chemical effect. Mn‐doped samples show greater catalytic activity compared to the pristine sample towards CO oxidation due to a synergistic Cu−Mn interaction. The catalytic performance of these oxides for MSR reaction is intriguing. Although the catalyst undergoes decomposition in the MSR atmosphere causing a decrease in methanol conversion during time‐on‐stream (TOS) tests, the activity can be regenerated by in‐situ or ex‐situ annealing in air. The notable catalytic activity and reversibility between pristine and decomposed form are very interesting.
Molecule and Synthesis Design of a Family of High Energy Density Materials Based on “565” Chemical Structure
Authors: Jin Xinghui , Wang Ling , Tan Ying , Ren Jing , Wang Zhongmin , Liu Yuling , Wang Luyao , Zhou Jianhua , Hu Bingcheng
Published: January 2018

A family of high energy density materials based on “565” chemical structure were designed and the spatial structure, heat of formation, detonation velocity, detonation pressure and sensitivity of each compound were investigated systematically by density functional theory. The results show that all the designed molecules possess high positive heat of formation (from 336.8 to 4135.7 kJ mol−1) and moderate detonation properties (detonation velocities range from 6.15 to 11.69 km s−1 and detonation pressures range from 16.4 to 68.28 GPa). Based on the values of detonation properties, impact sensitivities (range from 6.8 to 54.3 cm) and bond dissociation energies (range from 30.7 to 402.6 kJ mol−1), compounds A1, A2, A4 and B4 were selected as the potential high energy density materials. Then frontier molecular orbital, electrostatic potential on the surface and thermal dynamic parameters of these selected molecules were simulated to give a better understanding of their chemical and physical properties. Also, a reasonable synthetic path of the selected molecules were provided for further experimental synthesis and testing.
One‐Way Particle Transport Using Oscillatory Flow in Asymmetric Traps
Authors: Lee Jaesung , Burns Mark A.
Published: January 2018

One challenge of integrating of passive, microparticles manipulation techniques into multifunctional microfluidic devices is coupling the continuous‐flow format of most systems with the often batch‐type operation of particle separation systems. Here, a passive fluidic technique—one‐way particle transport—that can conduct microparticle operations in a closed fluidic circuit is presented. Exploiting pass/capture interactions between microparticles and asymmetric traps, this technique accomplishes a net displacement of particles in an oscillatory flow field. One‐way particle transport is achieved through four kinds of trap–particle interactions: mechanical capture of the particle, asymmetric interactions between the trap and the particle, physical collision of the particle with an obstacle, and lateral shift of the particle into a particle–trapping stream. The critical dimensions for those four conditions are found by numerically solving analytical mass balance equations formulated using the characteristics of the flow field in periodic obstacle arrays. Visual observation of experimental trap–particle dynamics in low Reynolds number flow (<0.01) confirms the validity of the theoretical predictions. This technique can transport hundreds of microparticles across trap rows in only a few fluid oscillations (<500 ms per oscillation) and separate particles by their size differences.
Sb Incorporation in Wurtzite and Zinc Blende InAs1−xSbx Branches on InAs Template Nanowires
Authors: Dahl Magnus , Namazi Luna , Zamani Reza R. , Dick Kimberly A.
Published: January 2018

The physical properties of material largely depend on their crystal structure. Nanowire growth is an important method for attaining metastable crystal structures in III–V semiconductors, giving access to advantageous electronic and surface properties. Antimonides are an exception, as growing metastable wurtzite structure has proven to be challenging. As a result, the properties of these materials remain unknown. One promising means of accessing wurtzite antimonides is to use a wurtzite template to facilitate their growth. Here, a template technique using branched nanowire growth for realizing wurtzite antimonide material is demonstrated. On wurtzite InAs trunks, InAs1−xSbx branch nanowires at different Sb vapor phase compositions are grown. For comparison, branches on zinc blende nanowire trunks are also grown under identical conditions. Studying the crystal structure and the material composition of the grown branches at different xv shows that the Sb incorporation is higher in zinc blende than in wurtzite. Branches grown on wurtzite trunks are usually correlated with stacking defects in the trunk, leading to the emergence of a zinc blende segment of higher Sb content growing parallel to the wurtzite structure within a branch. However, the average amount of Sb incorporated within the branch is determined by the vapor phase composition.
Ophthalmic artery Doppler for prediction of pre‐eclampsia: systematic review and meta‐analysis
Authors: Kalafat E. , Laoreti A. , Khalil A. , Da Silva Costa F. , Thilaganathan B.
Published: January 2018

Objective

To determine the accuracy of ophthalmic artery Doppler in pregnancy for the prediction of pre‐eclampsia (PE).

Methods

MEDLINE, EMBASE, CINAHL and The Cochrane Library were searched for relevant citations without language restrictions. Two reviewers independently selected studies that evaluated the accuracy of ophthalmic artery Doppler to predict the development of PE and extracted data to construct 2 × 2 tables. Individual patient data were obtained from the authors if available. A bivariate random‐effects model was used for the quantitative synthesis of data. Logistic regression analysis was employed to generate receiver–operating characteristics (ROC) curves and obtain optimal cut‐offs for each investigated parameter, and a bivariate analysis was employed using predetermined cut‐offs to obtain sensitivity and specificity values and generate summary ROC curves.

Results

A total of 87 citations matched the search criteria of which three studies, involving 1119 pregnancies, were included in the analysis. All included studies had clear description of the index and reference tests, avoidance of verification bias and adequate follow‐up. Individual patient data were obtained for all three included studies. First diastolic peak velocity of ophthalmic artery Doppler at a cut‐off of 23.3 cm/s showed modest sensitivity (61.0%; 95% CI, 44.2–76.1%) and specificity (73.2%; 95% CI, 66.9–78.7%) for the prediction of early‐onset PE (area under the ROC curve (AUC), 0.68; 95% CI, 0.61–0.76). The first diastolic peak velocity had a much lower sensitivity (39.0%; 95% CI, 20.6–61.0%), a similar specificity (73.2%; 95% CI, 66.9–78.7%) and a lower AUC (0.58; CI, 0.52–0.65) for the prediction of late‐onset PE. The pulsatility index of the ophthalmic artery did not show a clinically useful sensitivity or specificity at any cut‐off for early‐ or late‐onset PE. Peak ratio above 0.65 showed a similar diagnostic accuracy to that of the first diastolic peak velocity with an AUC of 0.67 (95% CI, 0.58–0.77) for early‐onset PE and 0.57 (95% CI, 0.51–0.63) for late‐onset disease.

Conclusions

Ophthalmic artery Doppler is a simple, accurate and objective technique with a standalone predictive value for the development of early‐onset PE equivalent to that of uterine artery Doppler evaluation. The relationship between ophthalmic Doppler indices and PE cannot be a consequence of trophoblast invasion and may be related to maternal hemodynamic adaptation to pregnancy. The findings of this review justify efforts to elucidate the effectiveness and underlying mechanism whereby two seemingly unrelated maternal vessels can be used for the prediction of a disease considered a ‘placental disorder’. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Characterization of estrous cycles and pregnancy in Somali wild asses (Equus africanus somaliensis) through fecal hormone analyses
Authors: Kozlowski Corinne P. , Clawitter Helen L. , Thier Tim , Fischer Martha T. , Asa Cheryl S.
Published: January 2018

Although reproduction in the domestic horse has been well described, less is known about reproduction in wild equids. This study describes endocrine patterns associated with estrous cycles and pregnancy for Somali wild asses (Equus africanus somaliensis), an endangered African equid. Fecal samples were collected three times per week for more than 2 years from five female Somali wild asses at the Saint Louis Zoo; progestagen and estrogen metabolites were quantified using commercially available immunoassays. Progestagen analysis indicated that cycle lengths were 27.2 ± 1.2 days and females cycled throughout the year. Progestagen levels during early pregnancy were low and not sustained above baseline until approximately 40 weeks prior to partition. Concentrations increased markedly around 16 weeks prior to delivery and peaked 2–3 weeks before birth. Fecal estrogen levels also increased significantly starting 40–45 weeks before parturition and reached their maximal value approximately 20 weeks prior to birth. Neither foal heat nor lactational suppression of estrus was observed, and females cycled within 45 days after delivery. These data are the first to describe the reproductive physiology of Somali wild asses. As the species faces increasing threats in the wild, this information may support conservation efforts by assisting with ex situ breeding programs.
Successful care and propagation of the endangered amargosa vole (Microtus californicus scirpensis) in captivity
Authors: Allan Nora , Pesapane Risa , Foley Janet , Clifford Deana
Published: January 2018

The Amargosa vole (Microtus californicus scirpensis) is a highlyendangered rodent endemic to a small stretch of the California portion of the Amargosa River basin in Inyo County's Mojave Desert. Although the Amargosa vole has survived in this naturally fragmented ecosystem for thousands of years, recent habitat degradation due to land development, water drainage, and marsh exploitation has further isolated the species and reduced its available habitat. As part of a conservation effort to preserve the species, a captive breeding population was established in 2014 to serve as an insurance colony and as a source of individuals to release into the wild as restored habitat becomes available. As this is the only captive colony for this species, there is little published information about appropriate care and husbandry for the Amargosa vole. Here we provide information about behavior, diet, reproduction, drug sensitivities, and diseases that affect successful captive care. We also provide recommendations for housing and disease management to preserve natural behaviors and defenses in captive‐born animals.
Cost‐Effectiveness of Minimally Invasive Esophagectomy for Esophageal Squamous Cell Carcinoma
Authors: Liu Chao‐Yu , Lin Chen‐Sung , Shih Chih‐Shiun , Huang Yuh‐An , Liu Chia‐Chuan , Cheng Chih‐Tao
Published: January 2018

Introduction

The cost‐effectiveness of minimally invasive esophagectomy (MIE) versus open esophagectomy (OE) for esophageal squamous cell carcinoma (ESCC) has not been established. Recent cost studies have shown that MIE is associated with a higher surgical expense, which is not consistently offset by savings through expedited post‐operative recovery, therefore suggesting a questionable benefit of MIE over OE from an economic point of view. In the current study, we compared the cost‐effectiveness of MIE versus OE for ESCC.

Materials and methods

Between April 2000 and December 2013, a total of 251 consecutive patients undergoing MIE or OE for ESCC were enrolled. After propensity score (PS)‐matching the MIE group with the OE group for clinical characteristics, 95 patients from each group were enrolled to compare the peri‐operative outcomes, long‐term survival, and cost.

Results

After PS‐matching, the baseline characteristics were not significantly different between groups. Perioperative outcomes were similar in both groups. MIE was superior to OE with respect to a shorter intensive care unit (ICU) stay, while the complication rate (except for hoarseness) and survival were similar. Post‐operative cost was significantly less in the MIE group due to a shorter ICU stay; however, reduced post‐operative cost failed to offset the higher surgical expense of MIE.

Conclusions

MIE for ESCC failed to show cost‐effectiveness regarding overall expense in our study, but costs less in the postoperative care, especially for ICU care. More cost studies on MIE in other health care systems are warranted to verify the cost‐effectiveness of MIE.
Mitigating replay attacks with ZigBee solutions
Authors: Farha Fadi , Chen Hongsong
Published: January 2018

The ZigBee wireless technology was developed by the ZigBee alliance and is a low-cost communication solution with low power consumption. 1,2 ZigBee applications are often embedded into electrical circuits that are widely used in home and building automation, PC peripherals and medical sensors. 3,4
Internal solitary wave generation by tidal flow over topography
Authors: Grimshaw R. , Helfrich K. R.
Published: January 2018

Oceanic internal solitary waves are typically generated by barotropic tidal flow over localised topography. Wave generation can be characterised by the Froude number $F=U/c_{0}$, where $U$ is the tidal flow amplitude and $c_{0}$ is the intrinsic linear long wave phase speed, that is the speed in the absence of the tidal current. For steady tidal flow in the resonant regime, $\unicode[STIX]{x1D6E5}_{m}<F-1<\unicode[STIX]{x1D6E5}_{M}$, a theory based on the forced Korteweg–de Vries equation shows that upstream and downstream propagating undular bores are produced. The bandwidth limits $\unicode[STIX]{x1D6E5}_{m,M}$ depend on the height (or depth) of the topographic forcing term, which can be either positive or negative depending on whether the topography is equivalent to a hole or a sill. Here the wave generation process is studied numerically using a forced Korteweg–de Vries equation model with time-dependent Froude number, $F(t)$, representative of realistic tidal flow. The response depends on $\unicode[STIX]{x1D6E5}_{max}=F_{max}-1$, where $F_{max}$ is the maximum of $F(t)$ over half of a tidal cycle. When $\unicode[STIX]{x1D6E5}_{max}<\unicode[STIX]{x1D6E5}_{m}$ the flow is always subcritical and internal solitary waves appear after release of the downstream disturbance. When $\unicode[STIX]{x1D6E5}_{m}<\unicode[STIX]{x1D6E5}_{max}<\unicode[STIX]{x1D6E5}_{M}$ the flow reaches criticality at its peak, producing upstream and downstream undular bores that are released as the tide slackens. When $\unicode[STIX]{x1D6E5}_{max}>\unicode[STIX]{x1D6E5}_{M}$ the tidal flow goes through the resonant regime twice, producing undular bores with each passage. The numerical simulations are for both symmetrical topography, and for asymmetric topography representative of Stellwagen Bank and Knight Inlet.
MOTIVATION AS QUALITY
Authors: Papi Mostafa
Published: January 2018

The study examined the predictions of regulatory fit theory (Higgins, 2000) in relation to task-based incidental vocabulary learning. A total of 189 English as a second language learners completed a vocabulary pretest, a regulatory focus questionnaire, an integrated reading/writing task, and finally an unannounced vocabulary posttest. The participants were randomly assigned to two task conditions. In the gain condition, they started the task with zero points and had to gain 75 points to enter a drawing to win one of three $100 gift cards; in the loss condition, they started with 100 points and had to avoid losing more than 25 points. Multiple regression results partly supported the regulatory fit predictions. Prevention individuals learned significantly more vocabulary items in the loss condition than in the gain condition; but promotion individuals did not learn significantly more vocabulary items in the gain condition than in the loss condition. Theoretical and pedagogical implications, and future research directions are discussed.
Laïcité, Republic and Nation in Post-Colonial France
Authors: GILDEA ROBERT
Published: January 2018

The question of ‘secularity’ (laïcité) has risen sharply up the French political agenda over the last twenty-five years. Ways in which it is defined and applied are hotly contested and lie at the nerve centre of wide debates about the nature of the Republic, French national identity and indeed of France's colonial past. According to an IFOP opinion poll in November 2015, 87 per cent of French people agreed that was important to respect laïcité at school, 84 per cent of respondents said that it was part of France's identity while 81 per cent thought that it was under threat in France. That said, they did not agree on what laïcité meant. For 32 per cent it meant separating religion from politics, for 27 per cent it meant ensuring liberty of conscience, while 17 per cent said it meant reducing the influence of religion in society. Historians, sociologists and political scientists as well as journalists and activists join battle on the question, and a selection of their recent contributions, from different angles and with different methodologies, are reviewed here.
Report Recommends Priorities for Earth Observations from Space
Authors: Showstack Randy
Published: January 2018

The new strategic plan, which builds on earlier road maps for observing the planet, identifies top targets for satellite scrutiny for the next decade.
Tuning microtubule dynamics to enhance cancer therapy by modulating FER-mediated CRMP2 phosphorylation
Authors: Zheng Yiyan , Sethi Ritika , Mangala Lingegowda S. , Taylor Charlotte , Goldsmith Juliet , Wang Ming , Masuda Kenta , Carrami Eli M. , Mannion David , Miranda Fabrizio , Herrero-Gonzalez Sandra , Hellner Karin , Chen Fiona , Alsaadi Abdulkhaliq , Albukhari Ashwag , Fotso Donatien Chedom , Yau Christopher , Jiang Dahai , Pradeep Sunila , Rodriguez-Aguayo Cristian , Lopez-Berestein Gabriel , Knapp Stefan , Gray Nathanael S. , Campo Leticia , Myers Kevin A. , Dhar Sunanda , Ferguson David , Bast Robert C. , Sood Anil K. , von Delft Frank , Ahmed Ahmed Ashour
Published: January 2018

Though used widely in cancer therapy, paclitaxel only elicits a response in a fraction of patients. A strong determinant of paclitaxel tumor response is the state of microtubule dynamic instability. However, whether the manipulation of this physiological process can be controlled to enhance paclitaxel response has not been tested. Here, we show a previously unrecognized role of the microtubule-associated protein CRMP2 in inducing microtubule bundling through its carboxy terminus. This activity is significantly decreased when the FER tyrosine kinase phosphorylates CRMP2 at Y479 and Y499. The crystal structures of wild-type CRMP2 and CRMP2-Y479E reveal how mimicking phosphorylation prevents tetramerization of CRMP2. Depletion of FER or reducing its catalytic activity using sub-therapeutic doses of inhibitors increases paclitaxel-induced microtubule stability and cytotoxicity in ovarian cancer cells and in vivo. This work provides a rationale for inhibiting FER-mediated CRMP2 phosphorylation to enhance paclitaxel on-target activity for cancer therapy.
UFD-2 is an adaptor-assisted E3 ligase targeting unfolded proteins
Authors: Hellerschmied Doris , Roessler Max , Lehner Anita , Gazda Linn , Stejskal Karel , Imre Richard , Mechtler Karl , Dammermann Alexander , Clausen Tim
Published: January 2018

Muscle development requires the coordinated activities of specific protein folding and degradation factors. UFD-2, a U-box ubiquitin ligase, has been reported to play a central role in this orchestra regulating the myosin chaperone UNC-45. Here, we apply an integrative in vitro and in vivo approach to delineate the substrate-targeting mechanism of UFD-2 and elucidate its distinct mechanistic features as an E3/E4 enzyme. Using Caenorhabditis elegans as model system, we demonstrate that UFD-2 is not regulating the protein levels of UNC-45 in muscle cells, but rather shows the characteristic properties of a bona fide E3 ligase involved in protein quality control. Our data demonstrate that UFD-2 preferentially targets unfolded protein segments. Moreover, the UNC-45 chaperone can serve as an adaptor protein of UFD-2 to poly-ubiquitinate unfolded myosin, pointing to a possible role of the UFD-2/UNC-45 pair in maintaining proteostasis in muscle cells.
Geometric isotope effect of deuteration in a hydrogen-bonded host–guest crystal
Authors: Shi Chao , Zhang Xi , Yu Chun-Hua , Yao Ye-Feng , Zhang Wen
Published: January 2018

Deuteration of a hydrogen bond by replacing protium (H) with deuterium (D) can cause geometric changes in the hydrogen bond, known as the geometric H/D isotope effect (GIE). Understanding the GIEs on global structures and bulk properties is of great importance to study structure–property relationships of hydrogen-bonded systems. Here, we report a hydrogen-bonded host–guest crystal, imidazolium hydrogen terephthalate, that exemplifies striking GIEs on its hydrogen bonds, phases, and bulk dielectric transition property. Upon deuteration, the donor–acceptor distance in the O–H···O hydrogen bonds in the host structure is found to increase, which results in a change in the global hydrogen-bonded supramolecular structure and the emergence of a new phase (i.e., isotopic polymorphism). Consequently, the dynamics of the confined guest, which depend on the internal pressure exerted by the host framework, are substantially altered, showing a downward shift of the dielectric switching temperature.
Signatures of Plexcitonic States in Molecular Electroluminescence
Authors: Bergfield Justin P. , Hendrickson Joshua R.
Published: January 2018

We develop a quantum master equation (QME) approach to investigate the electroluminesence (EL) of molecules confined between metallic electrodes and coupled to quantum plasmonic modes. Within our general state-based framework, we describe electronic tunneling, vibrational damping, environmental dephasing, and the quantum coherent dynamics of coupled quantum electromagnetic field modes. As an example, we calculate the STM-induced spontaneous emission of a tetraphenylporphyrin (TPP) molecule coupled to a nanocavity plasmon. In the weak molecular exciton-plasmon coupling regime we find excellent agreement with experiments, including above-threshold hot luminescence, an effect not described by previous semiclassical calculations. In the strong coupling regime, we analyze the spectral features indicative of the formation of plexcitonic states.
The exchange bias behavior of BiFeO3 nanoparticles with natural core-shell structure
Authors: Huang Fengzhen , Xu Xingyu , Lu Xiaomei , Zhou Min , Sang Hai , Zhu Jinsong
Published: January 2018

The surface and interface effects of small antiferromagnetic nanostructures are important on the modulation of their magnetic properties. In this report, temperature and particle size dependent magnetic exchange bias effect was investigated in BiFeO3 (BFO) nanoparticles that possess natural core-shell structure. Nonmonotonic variation of exchange bias field, interesting surface spin-glass state and improved exchange bias training effect are only obtained in 18 nm BFO particles. Based on comparative experiments on particles with different sizes, we found that the surface spins and the interaction among them show great effect on the interfacial exchange coupling of the core-shell structure, and thus are responsible for the peculiar exchange bias behavior in small BFO nanoparticles. Our work provides the effect of surface spin state on the magnetic characteristics of nanomaterials and will favor their applications on spintronic devices.
Surface temperatures in New York City: Geospatial data enables the accurate prediction of radiative heat transfer
Authors: Ghandehari Masoud , Emig Thorsten , Aghamohamadnia Milad
Published: January 2018

Despite decades of research seeking to derive the urban energy budget, the dynamics of thermal exchange in the densely constructed environment is not yet well understood. Using New York City as a study site, we present a novel hybrid experimental-computational approach for a better understanding of the radiative heat transfer in complex urban environments. The aim of this work is to contribute to the calculation of the urban energy budget, particularly the stored energy. We will focus our attention on surface thermal radiation. Improved understanding of urban thermodynamics incorporating the interaction of various bodies, particularly in high rise cities, will have implications on energy conservation at the building scale, and for human health and comfort at the urban scale. The platform presented is based on longwave hyperspectral imaging of nearly 100 blocks of Manhattan, in addition to a geospatial radiosity model that describes the collective radiative heat exchange between multiple buildings. Despite assumptions in surface emissivity and thermal conductivity of buildings walls, the close comparison of temperatures derived from measurements and computations is promising. Results imply that the presented geospatial thermodynamic model of urban structures can enable accurate and high resolution analysis of instantaneous urban surface temperatures.
Positive relationship between species richness and aboveground biomass across forest strata in a primary Pinus kesiya forest
Authors: Li Shuaifeng , Su Jianrong , Lang Xuedong , Liu Wande , Ou Guanglong
Published: January 2018

Both biodiversity and biomass are important variables in forest ecosystems, and the relationship between them is critical for ecosystem functioning and management. The primary Pinus kesiya forest is increasingly threatened by human disturbance in Yunnan Province. We observed that species richness had a positive impact on aboveground biomass across all forest vegetation layers, and this relationship was strongest in the herb layer. The asymptotic relationship between cumulative species number and aboveground biomass suggested that individual of Pinus kesiya trees with relatively large diameters contributed the majority of the aboveground biomass in the tall tree strata due to their strong competitive advantage over other tree species. Although aboveground biomass increased with stand age in the tall tree strata, climate factors and the soil nutrient regime affected the magnitude of the diversity-productivity relationship. Stand age had no significant effect on species richness and aboveground biomass in the forest understory. The effect of the positive diversity-productivity relationship of the tall trees on the shrub layer was negligible; the diversity-productivity relationship in the forest understory was significantly affected by the tall tree aboveground biomass. The tall trees have increased the strength of the positive diversity-productivity relationship in the forest understory.
Chloroplast genomes of Byrsonima species (Malpighiaceae): comparative analysis and screening of high divergence sequences
Authors: Menezes Alison P. A. , Resende-Moreira Luciana C. , Buzatti Renata S. O. , Nazareno Alison G. , Carlsen Monica , Lobo Francisco P. , Kalapothakis Evanguedes , Lovato Maria Bernadete
Published: January 2018

Byrsonima is the third largest genus (about 200 species) in the Malpighiaceae family, and one of the most common in Brazilian savannas. However, there is no molecular phylogeny available for the genus and taxonomic uncertainties at the generic and family level still remain. Herein, we sequenced the complete chloroplast genome of B. coccolobifolia and B. crassifolia, the first ones described for Malpighiaceae, and performed comparative analyses with sequences previously published for other families in the order Malpighiales. The chloroplast genomes assembled had a similar structure, gene content and organization, even when compared with species from other families. Chloroplast genomes ranged between 160,212 bp in B. crassifolia and 160,329 bp in B. coccolobifolia, both containing 115 genes (four ribosomal RNA genes, 28 tRNA genes and 83 protein-coding genes). We also identified sequences with high divergence that might be informative for phylogenetic inferences in the Malpighiales order, Malpighiaceae family and within the genus Byrsonima. The phylogenetic reconstruction of Malpighiales with these regions highlighted their utility for phylogenetic studies. The comparative analyses among species in Malpighiales provided insights into the chloroplast genome evolution in this order, including the presence/absence of three genes (infA, rpl32 and rps16) and two pseudogenes (ycf1 and rps19).
Recent inner ear specialization for high-speed hunting in cheetahs
Authors: Grohé Camille , Lee Beatrice , Flynn John J.
Published: January 2018

The cheetah,Acinonyx jubatus, is the fastest living land mammal. Because of its specialized hunting strategy, this species evolved a series of specialized morphological and functional body features to increase its exceptional predatory performance during high-speed hunting. Using high-resolution X-ray computed micro-tomography (μCT), we provide the first analyses of the size and shape of the vestibular system of the inner ear in cats, an organ essential for maintaining body balance and adapting head posture and gaze direction during movement in most vertebrates. We demonstrate that the vestibular system of modern cheetahs is extremely different in shape and proportions relative to other cats analysed (12 modern and two fossil felid species), including a closely-related fossil cheetah species. These distinctive attributes (i.e., one of the greatest volumes of the vestibular system, dorsal extension of the anterior and posterior semicircular canals) correlate with a greater afferent sensitivity of the inner ear to head motions, facilitating postural and visual stability during high-speed prey pursuit and capture. These features are not present in the fossil cheetahA. pardinensis, that went extinct about 126,000 years ago, demonstrating that the unique and highly specialized inner ear of the sole living species of cheetah likely evolved extremely recently, possibly later than the middle Pleistocene.
The anillin-related Int1 protein and the Sep7 septin collaborate to maintain cellular ploidy in Candida albicans
Authors: Orellana-Muñoz Sara , Dueñas-Santero Encarnación , Arnáiz-Pita Yolanda , del Rey Francisco , Correa-Bordes Jaime , Vázquez de Aldana Carlos R.
Published: January 2018

Variation in cell ploidy is a common feature of Candida albicans clinical isolates that are resistant to the antifungal drug fluconazole. Here, we report that the anillin-related protein Int1 interacts with septins for coupling cytokinesis with nuclear segregation. Loss of Int1 results in a rapid disassembly of duplicated septin rings from the bud neck at the onset of actomyosin ring contraction. Strikingly, this has no major impact on cytokinesis and septum formation. However, Int1 genetically interacts with the Sep7 septin, maintaining the diffusion barrier at the bud neck and guarantying a faithful nuclear segregation. Indeed, int1ΔΔ sep7ΔΔ mutant cells, in contrast to int1ΔΔ cdc10ΔΔ, undergo a premature activation of mitotic exit prior to the alignment of the mitotic spindle with the division axis, producing large multinucleated cells. Some of these multinucleated cells arise from trimeras similar to those observed upon fluconazole exposure. Finally, the defects in nuclear segregation could be in part due to the inability to maintain the Lte1 mitotic exit activator at the cortex of the daughter cell. These results suggest that Int1 and Sep7 play a role in maintaining genome stability by acting as a diffusion barrier for Lte1.
Fast modification on wheat straw outer surface by water vapor plasma and its application on composite material
Authors: Chen Weimin , Xu Yicheng , Shi Shukai , Cao Yizhong , Chen Minzhi , Zhou Xiaoyan
Published: January 2018

The presence of non-poplar extracts, cutin, and wax layer in the wheat straw outer surface (WOS) greatly limit its application in bio-composite preparation. In this study, a dielectric-barrier-discharge plasma using water vapor as feeding gas was used to fast modify the WOS. The morphology, free radical concentrations, surface chemical components, and contact angles of WOS before and after plasma modification were investigated. Wheat straw was further prepared into wheat straw-based composites (WSC) and its bonding strength was evaluated by a paper tension meter. The results showed that water vapor plasma leads to the appearance of surface roughness, the generation of massive free radicals, and the introduction of oxygen-containing groups. In addition, both initial and equilibrium contact angle and the surface total free energy were significantly increased after plasma modification. These results synergistically facilitate the spread and permeation of adhesive onto the WOS and thus improve the bonding strength of all prepared WSCs. A good linear relationship between bonding strength and surface roughness parameters, contact angles, and total free energy were observed. In general, this study provided a time-saving and cost-effective modification method to realize WSC manufacture.
Repeated five-day administration of L-BMAA, microcystin-LR, or as mixture, in adult C57BL/6 mice - lack of adverse cognitive effects
Authors: Myhre Oddvar , Eide Dag Marcus , Kleiven Synne , Utkilen Hans Christian , Hofer Tim
Published: January 2018

The cyanobacterial toxins β-methylamino-L-alanine (L-BMAA) and microcystin-LR (MC-LR; a potent liver toxin) are suspected to cause neurological disorders. Adult male C57BL/6JOlaHsd mice aged approximately 11 months were subcutaneously injected for five consecutive days with L-BMAA and microcystin-LR alone, or as a mixture. A dose-range study determined a tolerable daily dose to be ~31 µg MC-LR/kg BW/day based on survival, serum liver status enzymes, and relative liver and kidney weight. Mice tolerating the first one-two doses also tolerated the subsequent three-four doses indicating adaptation. The LD50 was 43–50 μg MC-LR/kg BW. Long-term effects (up to 10 weeks) on spatial learning and memory performance was investigated using a Barnes maze, were mice were given 30 µg MC-LR/kg BW and/or 30 mg L-BMAA/kg BW either alone or in mixture for five consecutive days. Anxiety, general locomotor activity, willingness to explore, hippocampal and peri-postrhinal cortex dependent memory was investigated after eight weeks using Open field combined with Novel location/Novel object recognition tests. Toxin exposed animals did not perform worse than controls, and MC-LR exposed animals performed somewhat better during the first Barnes maze re-test session. MC-LR exposed mice rapidly lost up to ~5% body weight, but regained weight from day eight.
The association of telomere attrition with first-onset stroke in Southern Chinese: a case-control study and meta-analysis
Authors: Li Jing , Feng Congrui , Li Liang , Yang Shujun , Chen Yu , Hui Rutai , Zhang Mei , Zhang Weili
Published: January 2018

The relationship between telomere length and stroke was inconsistent mostly due to different pathogenesis of subtypes, environment and genetics. We aimed to assess whether leukocyte telomere contributes to stroke in Southern Chinese by investigating a case-control study comprising 543 cases (224 atherothrombotic stroke, 94 hemorrhagic stroke and 225 lacunar infraction) and 616 controls and replicated the investigation in an independent study comprising 773 cases and 875 controls with the same diagnostic criteria. Telomere was inversely correlated with increasing age in controls (correlation coefficient γ = −0.28, P < 0.001) and in cases with atherothrombotic stroke (γ = −0.17, P = 0.012). Individuals within the lowest tertile of telomere showed a higher risk for atherothrombotic stroke [odds ratio 2.33, 95% confidence (CI) 1.42–3.83; P = 0.003], whereas had a lower presence of lacunar infarction (OR 0.49, 95% CI 0.30–0.81; P = 0.007). Similar results were obtained in the second replication study. A further meta-analysis showed a 12% increased pooled risk of ischemic stroke (95% CI 1.04–1.18) in relation to shorter telomere, but this association was stronger in the retrospective studies and in Asians when stratified by study design and ethnicity. Our data provided the first evidence that in Southern Chinese stroke population, leukocyte telomere is independently associated with atherothrombotic stroke and lacunar infarction.
Abnormal cerebellar processing of the neck proprioceptive information drives dysfunctions in cervical dystonia
Authors: Popa T. , Hubsch C. , James P. , Richard A. , Russo M. , Pradeep S. , Krishan S. , Roze E. , Meunier S. , Kishore A.
Published: January 2018

The cerebellum can influence the responsiveness of the primary motor cortex (M1) to undergo spike timing-dependent plastic changes through a complex mechanism involving multiple relays in the cerebello-thalamo-cortical pathway. Previous TMS studies showed that cerebellar cortex excitation can block the increase in M1 excitability induced by a paired-associative stimulation (PAS), while cerebellar cortex inhibition would enhance it. Since cerebellum is known to be affected in many types of dystonia, this bidirectional modulation was assessed in 22 patients with cervical dystonia and 23 healthy controls. Exactly opposite effects were found in patients: cerebellar inhibition suppressed the effects of PAS, while cerebellar excitation enhanced them. Another experiment comparing healthy subjects maintaining the head straight with subjects maintaining the head turned as the patients found that turning the head is enough to invert the cerebellar modulation of M1 plasticity. A third control experiment in healthy subjects showed that proprioceptive perturbation of the sterno-cleido-mastoid muscle had the same effects as turning the head. We discuss these finding in the light of the recent model of a mesencephalic head integrator. We also suggest that abnormal cerebellar processing of the neck proprioceptive information drives dysfunctions of the integrator in cervical dystonia.
Simultaneous detection of nucleotide excision repair events and apoptosis-induced DNA fragmentation in genotoxin-treated cells
Authors: Baek Soyun , Han Sueji , Kang Dukjin , Kemp Michael G. , Choi Jun-Hyuk
Published: January 2018

Novel in vivo excision assays for monitoring the excised oligonucleotide products of nucleotide excision repair in UV-irradiated cells have provided unprecedented views of the kinetics and genomic distribution of repair events. However, an unresolved issue is the fate of the excised oligonucleotide products of repair and their mechanism of degradation. Based on our observation that decreases in excised oligonucleotide abundance coincide with the induction of apoptotic signaling in UV-irradiated cells, we considered the possibility that caspase-mediated apoptotic signaling contributes to excised oligonucleotide degradation or to a general inhibition of the excision repair system. However, genetic and pharmacological approaches to inhibit apoptotic signaling demonstrated that caspase-mediated apoptotic signaling does not affect excision repair or excised oligonucleotide stability. Nonetheless, our assay for detecting soluble DNAs produced by repair also revealed the production of larger DNAs following DNA damage induction that was dependent on caspase activation. We therefore further exploited the versatility of this assay by showing that soluble DNAs produced by both nucleotide excision repair and apoptotic signaling can be monitored simultaneously with a diverse set of DNA damaging agents. Thus, our in vivo excision repair assay provides a sensitive measure of both repair kinetics and apoptotic signaling in genotoxin-treated cells.