bluuebunny/crossref_metadata_2025 huggingface dataset:
Affinity capillary electrophoresis in studying the complex formation equilibria of radionuclides in aqueous solutions
Authors: Sladkov Vladimir
Published: May 2016

Interaction of radionuclides with inorganic and organic species present in natural environment plays an important role in their eventual dispersion. The complex equilibria established in the aqueous phase cause significant changes in the migration properties of radionuclides. Affinity capillary electrophoresis (ACE) can be fruitful in studying these equilibria. This paper reviews the recent methodological advances of the use of ACE in studying the complex equilibria of radionuclides in aqueous solutions. Special attention is paid to the determination of a number of species involved in equilibrium, species constituents (number of ligands, protonated, deprotonated), the influence of ionic strength and temperature on stability constants of complex species formed. Use of ACE for the determination of the main thermodynamic parameters (the molar Gibbs energy (ΔrGm), the molar enthalpy (ΔrHm) and the molar entropy (ΔrSm)) of complex formation reactions is also discussed. These data are essential to predict dispersion of radionuclides in the natural environment.
A multi‐objective performance modelling framework for enabling self‐optimisation of cellular network topology and configurations
Authors: Farooq Hasan , Imran Ali , Abu‐Dayya Adnan
Published: May 2016

Cellular system optimisation, a cornerstone of cellular systems paradigm, requires new focus shift because of the emergence of plethora of new features shaping the cellular landscape. These features include self‐organising networks with added flavours of heterogeneity of cell sizes and base station types, adaptive antenna radiation patterns, energy efficiency, spatial homogeneity of service levels and focus shift from coverage to capacity. Moreover, to effectively tackle spatiotemporal dynamics of network conditions, a generic low‐complexity framework to quantify the key facets of performance, that is, capacity, quality of service and energy efficiency of the various network topology configurations (NTC), is needed for enabling self‐organising networks empowered cellular system optimisation on the fly. In this paper, we address this problem and present a performance characterisation framework that quantifies the multiple performance aspects of a given heterogeneous NTC through a unified set of metrics that are derived as function of key optimisation parameters and also present a cross comparison of a wide range of potential NTCs. Moreover, we propose a low‐complexity heuristic approach for holistic optimisation of future heterogeneous cellular systems for joint optimality in the multiple desired performance indicators. The performance characterisation framework also provides quantitative insights into the new tradeoffs involved in optimisation of emerging heterogeneous networks and can pave the way for much needed further research in this area. Copyright © 2016 John Wiley & Sons, Ltd.
Higher Gemcitabine Dose Was Associated With Better Outcome of Osteosarcoma Patients Receiving Gemcitabine‐Docetaxel Chemotherapy
Authors: Lee Jun Ah , Jeon Dae‐Geun , Cho Wan Hyeong , Song Won Seok , Yoon Hoi Soo , Park Hyeon Jin , Park Byung Kiu , Choi Hyoung Soo , Ahn Hyo Seop , Lee Ji Won , Yoo Keon Hee , Sung Ki Woong , Koo Hong Hoe , Kang Hyoung Jin , Park Kyung Duk , Shin Hee Young , Koh Kyung‐Nam , Im Ho Joon , Seo Jong Jin , Lim Yeon Jung , Baek Hee Jo , Kook Hoon
Published: May 2016

Background

Efficacy of gemcitabine and docetaxel (GEM + DOC) chemotherapy in patients with recurrent or refractory osteosarcoma was evaluated.

Methods

Data of 53 patients from 9 institutions, who received GEM (675 or 900 mg/m2 on days 1 and 8) and DOC (100 mg/m2 on day 8), were retrospectively reviewed.

Results

GEM + DOC was administered as adjuvant (n = 25) or palliative chemotherapy (n = 28). Patients received a median 3 courses (range, 1−10 courses). Objective response rate (CR + PR, where CR is complete response and PR is partial response) and disease control rate (CR+ PR + SD, where SD is stable disease) were 14.3% and 28.6%, respectively. Disease control rate was higher in patients receiving 900 mg/m2 GEM than in patients receiving 675 mg/m2 (50.0% vs. 12.5%, P = 0.03). Higher GEM dose was associated with better survival, both in adjuvant (1‐year overall survival, 90.9 ± 8.7% vs. 38.5 ± 13.5%, P = 0.002) and palliative settings (50.0 ± 14.4% vs. 31.3 ± 11.6%, P = 0.04).

Conclusions

Further studies are necessary to investigate the efficacy of more aggressive and higher doses of GEM + DOC chemotherapy in osteosarcoma.
Pediatric Sarcomas Are Targetable by MR‐Guided High Intensity Focused Ultrasound (MR‐HIFU): Anatomical Distribution and Radiological Characteristics
Authors: Shim Jenny , Staruch Robert M. , Koral Korgun , Xie Xian‐Jin , Chopra Rajiv , Laetsch Theodore W.
Published: May 2016

Background

Despite intensive therapy, children with metastatic and recurrent sarcoma or neuroblastoma have a poor prognosis. Magnetic resonance guided high intensity focused ultrasound (MR‐HIFU) is a noninvasive technique allowing the delivery of targeted ultrasound energy under MR imaging guidance. MR‐HIFU may be used to ablate tumors without ionizing radiation or target chemotherapy using hyperthermia. Here, we evaluated the anatomic locations of tumors to assess the technical feasibility of MR‐HIFU therapy for children with solid tumors.

Procedure

Patients with sarcoma or neuroblastoma with available cross‐sectional imaging were studied. Tumors were classified based on the location and surrounding structures within the ultrasound beam path as (i) not targetable, (ii) completely or partially targetable with the currently available MR‐HIFU system, and (iii) potentially targetable if a respiratory motion compensation technique was used.

Results

Of the 121 patients with sarcoma and 61 patients with neuroblastoma, 64% and 25% of primary tumors were targetable at diagnosis, respectively. Less than 20% of metastases at diagnosis or relapse were targetable for both sarcoma and neuroblastoma. Most targetable lesions were located in extremities or in the pelvis. Respiratory motion compensation may increase the percentage of targetable tumors by 4% for sarcomas and 10% for neuroblastoma.

Conclusions

Many pediatric sarcomas are localized at diagnosis and are targetable by current MR‐HIFU technology. Some children with neuroblastoma have bony tumors targetable by MR‐HIFU at relapse, but few newly diagnosed children with neuroblastoma have tumors amenable to MR‐HIFU therapy. Clinical trials of MR‐HIFU should focus on patients with anatomically targetable tumors.
Short‐term Clinical Course of Knee Pain in Children and Adolescents: A Feasibility Study Using Electronic Methods of Data Collection
Authors: Swain Michael S. , Kamper Steven J. , Maher Chris G. , Latimer Jane , Broderick Carolyn , McKay Damien , Henschke Nicholas
Published: May 2016

Background and Purpose

Musculoskeletal disorders, such as knee pain, are common in children and adolescents, but there is a lack of high quality research that evaluates the clinical course of these conditions. The objective of this study was to evaluate the feasibility of conducting a prospective study of children and adolescents with knee pain using electronic methods of data collection.

Methods

Children and adolescents with knee pain that presented to primary care physiotherapy clinics were enrolled and followed‐up on a weekly basis via short messaging service (SMS) until their knee pain had recovered (i.e. two consecutive weeks of no pain). Feasibility was assessed in terms of recruitment, retention and response rates to SMS and an online questionnaire. Baseline and 6‐month follow‐up measures included pain, disability, physical function, physical activity and health related quality of life. Kaplan–Meier survival analysis was used to estimate the median time to knee pain recovery.

Results

Thirty participants (mean age 13.0 ± 2.2 years, 53% boys) were recruited over 26 months. The overall response rate to weekly SMS follow‐up was 71.3% (809 received/1135 sent). One third of participants stopped responding to SMS prior to recovery, and these participants typically had a much lower response rate during the time they remained in the study. At 6‐month follow‐up, 80% of the cohort completed the final online questionnaire, and 29% of participants still reported current knee pain (≥1/10 VAS). The median time for knee pain recovery was 8 weeks (95%CI: 5, 10).

Conclusion

Electronic data collection alone seems insufficient to track pain recovery in young people and may need to be supplemented with more traditional data collection methods. Researchers should consider further measures to address slow recruitment rates and high attrition when designing large prospective studies of children and adolescents in the future. Copyright © 2016 John Wiley & Sons, Ltd.
Modeling the WorldView-derived seasonal velocity evolution of Kennicott Glacier, Alaska
Authors: ARMSTRONG W. H. , ANDERSON R. S. , ALLEN JEFFERY , RAJARAM H.
Published: May 2016

Glacier basal motion generates diurnal to multi-annual fluctuations in glacier velocity and mass flux. Understanding these fluctuations is important for prediction of future sea-level rise and for gaining insight into glacier physics and erosion. Here, we derive glacier velocity through cross-correlation of WorldView satellite imagery to document the evolution of ice surface velocity on Kennicott Glacier, Alaska, over the 2013 melt season. The summer speedup is spatially uniform over a ~12 km2area, over which the spring velocity varies significantly. Velocity increases by 1.4-fold to tenfold across the study domain, with larger values where spring velocities are low. To investigate the cross-glacier distribution of basal motion required to explain the observed surface speedup, we employ a two-dimensional cross-sectional glacier flow model. We find the model is insensitive to the spatial distribution of basal slip because stress gradient ice coupling diffuses the surface expression of the basal velocity field. While the temporal evolution of the subglacial hydrologic system is critical for predicting a glacier's response to meltwater inputs, our work suggests that glacier and ice-sheet models do not require a detailed representation of subglacial hydrology to accurately capture the spatial pattern of glacier speedup.
The combined effects of soya isoflavones and resistant starch on equol production and trabecular bone loss in ovariectomised mice
Authors: Tousen Yuko , Matsumoto Yu , Matsumoto Chiho , Nishide Yoriko , Nagahata Yuya , Kobayashi Isao , Ishimi Yoshiko
Published: May 2016

Equol is a metabolite of the soya isoflavone (ISO) daidzein that is produced by intestinal microbiota. Equol has greater oestrogenic activity compared with other ISO, and it prevents bone loss in postmenopausal women. Resistant starch (RS), which has a prebiotic activity and is a dietary fibre, was reported to promote equol production. Conversely, the intestinal microbiota is reported to directly regulate bone health by reducing inflammatory cytokine levels and T-lymphocytes in bone. The present study evaluated the combined effects of diet supplemented with ISO and RS on intestinal microbiota, equol production, bone mineral density (BMD) and inflammatory gene expression in the bone marrow of ovariectomised (OVX) mice. Female ddY strain mice, aged 8 weeks, were either sham-operated (Sham, n 7) or OVX. OVX mice were randomly divided into the following four groups (seven per group): OVX control (OVX); OVX fed 0·05 % ISO diet (OVX+ISO); OVX fed 9 % RS diet (OVX+RS); and OVX fed 0·05 % ISO- and 9 % RS diet (OVX+ISO+RS). After 6 weeks, treatment with the combination of ISO and RS increased equol production, prevented the OVX-induced decline in trabecular BMD in the distal femur by modulating the enteric environment and altered OVX-induced inflammation-related gene expression in the bone marrow. However, there were no significant differences in bone parameters between the ISO+RS and ISO-alone groups in OVX mice. Our findings suggest that the combination of ISO and RS might alter intestinal microbiota and immune status in the bone marrow, resulting in attenuated bone resorption in OVX mice.
Crude protein levels in diets of lactating goats: nitrogen balance, urea excretion and microbial protein synthesis
Authors: DE JESUS DOS SANTOS E. , ALBUQUERQUE PEREIRA M. L. , PEREIRA DE FIGUEIREDO M. , DE OLIVEIRA SILVA H. G. , FERREIRA DA CRUZ J. , OLIVEIRA BARRETO F. , BORGES SOUSA L.
Published: May 2016

The experiment, conducted at Bahia, Brazil, from May to August 2010, aimed to evaluate the nitrogen (N) balance, urea excretion and microbial protein synthesis in lactating goats fed pelleted concentrates with the addition of crude protein (CP), obtained by replacing alfalfa hay with soybean meal. The diets consisted of different levels of CP and 200 g of roughage (Tifton 85 hay)/kg. Maize and mesquite bran were used as the energy source, with maize replaced by mesquite bran in the ratio of 1·7:1. Eight female Saanen goats were used, confined in individual pens and allocated to a 4 × 4 Latin square design. The N balance in the body was positive, and loss of body weight (–0·03 g/day) was observed for the diet with 190 g CP/kg. The concentration (mg/dl) of urea in urine, milk and blood plasma was positively influenced in a linear form, and the highest rate of increase was found in urine, with 2 mg/dl for every 10 g CP/kg added to the diet. The microbial protein synthesis was not affected, but the diets reduced the microbial protein (44 g/day) and its ruminal production efficiency (30 g/kg total digestible nutrients). The levels above 190 g of CP are not recommended because of the energy expenditure required to excrete the urea.
Enhanced Monte Carlo localization incorporating a mechanism for preventing premature convergence
Authors: Chien Chiang-Heng , Wang Wei-Yen , Jo Jun , Hsu Chen-Chien
Published: May 2016

In this paper, we propose an enhanced Monte Carlo localization (EMCL) algorithm for mobile robots, which deals with the premature convergence problem in global localization as well as the estimation error existing in pose tracking. By incorporating a mechanism for preventing premature convergence (MPPC), which uses a “reference relative vector” to modify the weight of each sample, exploration of a highly symmetrical environment can be improved. As a consequence, the proposed method has the ability to converge particles toward the global optimum, resulting in successful global localization. Furthermore, by applying the unscented Kalman Filter (UKF) to the prediction state and the previous state of particles in Monte Carlo Localization (MCL), an EMCL can be established for pose tracking, where the prediction state is modified by the Kalman gain derived from the modified prior error covariance. Hence, a better approximation that reduces the discrepancy between the state of the robot and the estimation can be obtained. Simulations and practical experiments confirmed that the proposed approach can improve the localization performance in both global localization and pose tracking.
The significant past and insignificant archaeologists. Who informs the public about their ‘national’ past? The case of Romania
Authors: Popa Cătălin Nicolae
Published: May 2016

This paper addresses the role of archaeologists in informing the public about a fundamental component of contemporary Romanian identity: the Dacian heritage. I start by exploring how the Dacians and Romanians came to be connected, a process that resulted from a combination of nationalistic zeal on behalf of archaeologists and the nationalist propaganda of the Ceauşescu regime during the 1970s and 1980s. I then move to the present-day situation, where I argue that archaeologists have reduced themselves to having a minor role in the public sphere, while discussions about the Dacians are dominated by two main players: pseudoarchaeologists and re-enactors. This state of affairs delegitimizes Romanian archaeology and places self-declared specialists and enthusiasts in the position of experts. Some of the Dacian narratives produced in this environment are infused with strong nationalist messages and have the potential to fuel extreme right-wing and even xenophobic movements. Consequently, in the final part of the paper, I recommend that Romanian archaeologists should challenge the representations and interpretations of pseudoarchaeologists and re-enactors. Moreover, academics should make it a priority to re-engage with the public and disseminate their work to a broad audience in a convincing manner.
Hammers and nails. A response to Lindstrøm and to Olsen and Witmore
Authors: Sørensen Tim Flohr
Published: May 2016

Two contrasting arguments on the merits of symmetrical archaeology and an associated discussion of object agency appeared in a recent issue ofArchaeological dialogues(Lindstrøm 2015; Olsen and Witmore 2015). While Torill Christine Lindstrøm extends a thorough, yet hardly new, criticism of the notion of object agency and of symmetrical archaeology, Bjørnar Olsen and Christopher Witmore provide a clarification in its defence (even though their article is oddly categorized byArchaeological dialoguesas a ‘provocation’). In this reaction article, I take issue with a number of arguments by Lindstrøm and by Olsen and Witmore: first of all, I challenge Lindstrøm's representation of object agency, which I believe is in need of corrections. Second, I contend that Lindstrøm fails to identify a number of fundamental contributions within the framework of symmetrical archaeology, thus allowing her to caricature symmetrical archaeology as ‘old wine in new bags’. Third, even though Olsen and Witmore's defence offers helpful clarifications, I believe that their contribution invites us to discuss the vocabulary of symmetrical archaeology, scrutinizing why there is an apparent tendency to misunderstand its arguments and merits. Lastly, I take issue with Lindstrøm's dismissal of ‘different ontologies’ as a result of political correctness.
Suppression of KRas-mutant cancer through the combined inhibition of KRAS with PLK1 and ROCK
Authors: Wang Jieqiong , Hu Kewen , Guo Jiawei , Cheng Feixiong , Lv Jing , Jiang Wenhao , Lu Weiqiang , Liu Jinsong , Pang Xiufeng , Liu Mingyao
Published: May 2016

No effective targeted therapies exist for cancers with somatic KRAS mutations. Here we develop a synthetic lethal chemical screen in isogenic KRAS-mutant and wild-type cells to identify clinical drug pairs. Our results show that dual inhibition of polo-like kinase 1 and RhoA/Rho kinase (ROCK) leads to the synergistic effects in KRAS-mutant cancers. Microarray analysis reveals that this combinatory inhibition significantly increases transcription and activity of cyclin-dependent kinase inhibitor p21WAF1/CIP1, leading to specific G2/M phase blockade in KRAS-mutant cells. Overexpression of p21WAF1/CIP1, either by cDNA transfection or clinical drugs, preferentially impairs the growth of KRAS-mutant cells, suggesting a druggable synthetic lethal interaction between KRAS and p21WAF1/CIP1. Co-administration of BI-2536 and fasudil either in the LSL-KRASG12D mouse model or in a patient tumour explant mouse model of KRAS-mutant lung cancer suppresses tumour growth and significantly prolongs mouse survival, suggesting a strong synergy in vivo and a potential avenue for therapeutic treatment of KRAS-mutant cancers.
ISG15 deficiency and increased viral resistance in humans but not mice
Authors: Speer Scott D. , Li Zhi , Buta Sofija , Payelle-Brogard Béatrice , Qian Li , Vigant Frederic , Rubino Erminia , Gardner Thomas J. , Wedeking Tim , Hermann Mark , Duehr James , Sanal Ozden , Tezcan Ilhan , Mansouri Nahal , Tabarsi Payam , Mansouri Davood , Francois-Newton Véronique , Daussy Coralie F. , Rodriguez Marisela R. , Lenschow Deborah J. , Freiberg Alexander N. , Tortorella Domenico , Piehler Jacob , Lee Benhur , García-Sastre Adolfo , Pellegrini Sandra , Bogunovic Dusan
Published: May 2016

ISG15 is an interferon (IFN)-α/β-induced ubiquitin-like protein. It exists as a free molecule, intracellularly and extracellularly, and conjugated to target proteins. Studies in mice have demonstrated a role for Isg15 in antiviral immunity. By contrast, human ISG15 was shown to have critical immune functions, but not in antiviral immunity. Namely, free extracellular ISG15 is crucial in IFN-γ-dependent antimycobacterial immunity, while free intracellular ISG15 is crucial for USP18-mediated downregulation of IFN-α/β signalling. Here we describe ISG15-deficient patients who display no enhanced susceptibility to viruses in vivo, in stark contrast to Isg15-deficient mice. Furthermore, fibroblasts derived from ISG15-deficient patients display enhanced antiviral protection, and expression of ISG15 attenuates viral resistance to WT control levels. The species-specific gain-of-function in antiviral immunity observed in ISG15 deficiency is explained by the requirement of ISG15 to sustain USP18 levels in humans, a mechanism not operating in mice.
Super-resolution microscopy reveals structural diversity in molecular exchange among peptide amphiphile nanofibres
Authors: da Silva Ricardo M. P. , van der Zwaag Daan , Albertazzi Lorenzo , Lee Sungsoo S. , Meijer E. W. , Stupp Samuel I.
Published: May 2016

The dynamic behaviour of supramolecular systems is an important dimension of their potential functions. Here, we report on the use of stochastic optical reconstruction microscopy to study the molecular exchange of peptide amphiphile nanofibres, supramolecular systems known to have important biomedical functions. Solutions of nanofibres labelled with different dyes (Cy3 and Cy5) were mixed, and the distribution of dyes inserting into initially single-colour nanofibres was quantified using correlative image analysis. Our observations are consistent with an exchange mechanism involving monomers or small clusters of molecules inserting randomly into a fibre. Different exchange rates are observed within the same fibre, suggesting that local cohesive structures exist on the basis of β-sheet discontinuous domains. The results reported here show that peptide amphiphile supramolecular systems can be dynamic and that their intermolecular interactions affect exchange patterns. This information can be used to generate useful aggregate morphologies for improved biomedical function.
Inhibition of the hexosamine biosynthetic pathway promotes castration-resistant prostate cancer
Authors: Kaushik Akash K. , Shojaie Ali , Panzitt Katrin , Sonavane Rajni , Venghatakrishnan Harene , Manikkam Mohan , Zaslavsky Alexander , Putluri Vasanta , Vasu Vihas T. , Zhang Yiqing , Khan Ayesha S. , Lloyd Stacy , Szafran Adam T. , Dasgupta Subhamoy , Bader David A. , Stossi Fabio , Li Hangwen , Samanta Susmita , Cao Xuhong , Tsouko Efrosini , Huang Shixia , Frigo Daniel E. , Chan Lawrence , Edwards Dean P. , Kaipparettu Benny A. , Mitsiades Nicholas , Weigel Nancy L. , Mancini Michael , McGuire Sean E. , Mehra Rohit , Ittmann Michael M. , Chinnaiyan Arul M. , Putluri Nagireddy , Palapattu Ganesh S. , Michailidis George , Sreekumar Arun
Published: May 2016

The precise molecular alterations driving castration-resistant prostate cancer (CRPC) are not clearly understood. Using a novel network-based integrative approach, here, we show distinct alterations in the hexosamine biosynthetic pathway (HBP) to be critical for CRPC. Expression of HBP enzyme glucosamine-phosphate N-acetyltransferase 1 (GNPNAT1) is found to be significantly decreased in CRPC compared with localized prostate cancer (PCa). Genetic loss-of-function ofGNPNAT1in CRPC-like cells increases proliferation and aggressiveness,in vitroandin vivo. This is mediated by either activation of the PI3K-AKT pathway in cells expressing full-length androgen receptor (AR) or by specific protein 1 (SP1)-regulated expression of carbohydrate response element-binding protein (ChREBP) in cells containing AR-V7 variant. Strikingly, addition of the HBP metabolite UDP-N-acetylglucosamine (UDP-GlcNAc) to CRPC-like cells significantly decreases cell proliferation, bothin-vitroand in animal studies, while also demonstrates additive efficacy when combined with enzalutamidein-vitro. These observations demonstrate the therapeutic value of targeting HBP in CRPC.
Decoupling optical function and geometrical form using conformal flexible dielectric metasurfaces
Authors: Kamali Seyedeh Mahsa , Arbabi Amir , Arbabi Ehsan , Horie Yu , Faraon Andrei
Published: May 2016

Physical geometry and optical properties of objects are correlated: cylinders focus light to a line, spheres to a point and arbitrarily shaped objects introduce optical aberrations. Multi-functional components with decoupled geometrical form and optical function are needed when specific optical functionalities must be provided while the shapes are dictated by other considerations like ergonomics, aerodynamics or aesthetics. Here we demonstrate an approach for decoupling optical properties of objects from their physical shape using thin and flexible dielectric metasurfaces which conform to objects’ surface and change their optical properties. The conformal metasurfaces are composed of silicon nano-posts embedded in a polymer substrate that locally modify near-infrared (λ=915 nm) optical wavefronts. As proof of concept, we show that cylindrical lenses covered with metasurfaces can be transformed to function as aspherical lenses focusing light to a point. The conformal metasurface concept is highly versatile for developing arbitrarily shaped multi-functional optical devices.
Geometric spin echo under zero field
Authors: Sekiguchi Yuhei , Komura Yusuke , Mishima Shota , Tanaka Touta , Niikura Naeko , Kosaka Hideo
Published: May 2016

Spin echo is a fundamental tool for quantum registers and biomedical imaging. It is believed that a strong magnetic field is needed for the spin echo to provide long memory and high resolution, since a degenerate spin cannot be controlled or addressed under a zero magnetic field. While a degenerate spin is never subject to dynamic control, it is still subject to geometric control. Here we show the spin echo of a degenerate spin subsystem, which is geometrically controlled via a mediating state split by the crystal field, in a nitrogen vacancy centre in diamond. The demonstration reveals that the degenerate spin is protected by inherent symmetry breaking called zero-field splitting. The geometric spin echo under zero field provides an ideal way to maintain the coherence without any dynamics, thus opening the way to pseudo-static quantum random access memory and non-invasive biosensors.
Diverse Chemistry of Stable Hydronitrogens, and Implications for Planetary and Materials Sciences
Authors: Qian Guang-Rui , Niu Haiyang , Hu Chao-Hao , Oganov Artem R. , Zeng Qingfeng , Zhou Huai-Ying
Published: May 2016

Nitrogen hydrides, e.g., ammonia (NH3), hydrazine (N2H4) and hydrazoic acid (HN3), are compounds of great fundamental and applied importance. Their high-pressure behavior is important because of their abundance in giant planets and because of the hopes of discovering high-energy-density materials. Here, we have performed a systematic investigation on the structural stability of N-H system in a pressure range up to 800 GPa through evolutionary structure prediction. Surprisingly, we found that high pressure stabilizes a series of previously unreported compounds with peculiar structural and electronic properties, such as the N4H, N3H, N2H and NH phases composed of nitrogen backbones, the N9H4 phase containing two-dimensional metallic nitrogen planes and novel N8H, NH2, N3H7, NH4 and NH5 molecular phases. Another surprise is that NH3 becomes thermodynamically unstable above ~460 GPa. We found that high-pressure chemistry of hydronitrogens is much more diverse than hydrocarbon chemistry at normal conditions, leading to expectations that N-H-O and N-H-O-S systems under pressure are likely to possess richer chemistry than the known organic chemistry. This, in turn, opens a possibility of nitrogen-based life at high pressure. The predicted phase diagram of the N-H system also provides a reference for synthesis of high-energy-density materials.
Investigations of metastable Ca2IrO4 epitaxial thin-films: systematic comparison with Sr2IrO4 and Ba2IrO4
Authors: Souri M. , Gruenewald J. H. , Terzic J. , Brill J. W. , Cao G. , Seo S. S. A.
Published: May 2016

We have synthesized thermodynamically metastable Ca2IrO4 thin-films on YAlO3 (110) substrates by pulsed laser deposition. The epitaxial Ca2IrO4 thin-films are of K2NiF4-type tetragonal structure. Transport and optical spectroscopy measurements indicate that the electronic structure of the Ca2IrO4 thin-films is similar to that of Jeff = 1/2 spin-orbit-coupled Mott insulator Sr2IrO4 and Ba2IrO4, with the exception of an increased gap energy. The gap increase is to be expected in Ca2IrO4 due to its increased octahedral rotation and tilting, which results in enhanced electron-correlation, U/W. Our results suggest that the epitaxial stabilization growth of metastable-phase thin-films can be used effectively for investigating layered iridates and various complex-oxide systems.
High-Q side-coupled semi-2D-photonic crystal cavity
Authors: Zhang Jianhao , Liu Weixi , Shi Yaocheng , He Sailing
Published: May 2016

High-Q semi-2D-photonic crystal cavities with a tapered edge and side-coupled bus waveguide are demonstrated. With a quadratic design, the unloaded cavity presents a theoretical ultrahigh quality factor up to 6.7 × 107 for the condition that there are mere 34 holes in the propagated direction, which is pretty close to the 2D and 1D counterpart. Combined with a side-coupled bus waveguide, an all-pass-type cavity with a loaded quality factor (Q) of over 2.4 × 104 and an extinction ratio over 10 dB are experimentally demonstrated. An experimental loaded Q up to 1.1 × 105 are also achieved by tuning the coupling between the cavity and the bus waveguide, which is much larger than any reported surface-mode cavity. This cavity is quite suitable for sensors, filters and especially optomechanical devices thanks to the mechanical stability of the cavity and flexibility of the bus waveguide.
Diverse mechanisms shape the evolution of virulence factors in the potato late blight pathogen Phytophthora infestans sampled from China
Authors: Wu E-Jiao , Yang Li-Na , Zhu Wen , Chen Xiao-Mei , Shang Li-Ping , Zhan Jiasui
Published: May 2016

Evolution of virulence in plant pathogens is still poorly understood but the knowledge is important for the effective use of plant resistance and sustainable disease management. Spatial population dynamics of virulence, race and SSR markers in 140 genotypes sampled from seven geographic locations in China were compared to infer the mechanisms driving the evolution of virulence in Phytophthora infestans (P. infestans). All virulence types and a full spectrum of race complexity, ranging from the race able to infect the universally susceptible cultivar only to all differentials, were detected. Eight and two virulence factors were under diversifying and constraining selection respectively while no natural selection was detected in one of the virulence types. Further analyses revealed excesses in simple and complex races but deficiency in intermediate race and negative associations of annual mean temperature at the site from which pathogen isolates were collected with frequency of virulence to differentials and race complexity in the pathogen populations. These results suggest that host selection may interact with other factors such as climatic conditions in determining the evolutionary trajectory of virulence and race structure in P. infestans and global warming may slow down the emergence of new virulence in the pathogen.
Enhanced power factor via the control of structural phase transition in SnSe
Authors: Yu Hulei , Dai Shuai , Chen Yue
Published: May 2016

Tin selenide has attracted much research interest due to its unprecedentedly high thermoelectric figure of merit (ZT). For real applications, it is desirable to increase the ZT value in the lower-temperature range, as the peak ZT value currently exists near the melting point. It is shown in this paper that the structural phase transition plays an important role in boosting the ZT value of SnSe in the lower-temperature range, as the Cmcm phase is found to have a much higher power factor than the Pnma phase. Furthermore, hydrostatic pressure is predicted to be extremely effective in tuning the phase transition temperature based on ab-initio molecular dynamic simulations; a remarkable decrease in the phase transition temperature is found when a hydrostatic pressure is applied. Dynamical stabilities are investigated based on phonon calculations, providing deeper insight into the pressure effects. Accurate band structures are obtained using the modified Becke-Johnson correction, allowing reliable prediction of the electrical transport properties. The effects of hydrostatic pressure on the thermal transport properties are also discussed. Hydrostatic pressure is shown to be efficient in manipulating the transport properties via the control of phase transition temperature in SnSe, paving a new path for enhancing its thermoelectric efficiency.
Triboluminescence dominated by crystallographic orientation
Authors: Wang Kuifang , Ma Liran , Xu Xuefeng , Wen Shizhu , Luo Jianbin
Published: May 2016

Triboluminescence (TL) is an optical phenomenon that has a long and varied history with broad applications, such as damage detection, X-ray source and mass health monitoring sensor. So far, the properties and mechanisms of TL remain not completely understood. The TL properties emitted during the sliding contact between Al2O3 and SiO2 surfaces were studied along different crystallographic orientations. In this study, the TL intensity of Al2O3 was significantly enhanced as Al2O3 surface was along a particular crystallographic orientation, which is an unconventional phenomenon. TL enhancement of Al2O3 was not affected by air atmosphere and atomic stocking mode of Al2O3. The enhancement mechanism of Al2O3 may be influenced by the surface state of Al2O3. This work provides a new method to control the intensity of TL and novel ideas to elucidate the TL mechanism.
Effects of biotic and abiotic factors on phenotypic partitioning of wing morphology and development in Sclerodermus pupariae (Hymenoptera: Bethylidae)
Authors: Wang Xiaoyi , Wei Ke , Yang Zhongqi , Jennings David E. , Duan Jian J.
Published: May 2016

Wing phenotype polymorphism is commonly observed in insects, yet little is known about the influence of environmental cues on the development or expression of the alternative phenotypes. Here, we report how both biotic and abiotic factors affect the wing morph differentiation of a bethylid parasitoid Sclerodermus pupariae. The percentage of winged female parasitoid progeny increased exponentially with temperature between 20 °C to 30 °C. Low intensity light and short-day photoperiod conditions also significantly induced the development of winged morphs. Interestingly, wingless maternal parasitoids produced more winged progeny. Furthermore, the degree of wing dimorphism was significantly influenced by the interactions between light intensity and maternal wing morphs. The percentage of winged female progeny was not significantly influenced by foundress densities, but increased significantly with parasitoid brood sizes. However, the percentage of male progeny increased significantly with the densities of maternal parasitoids. Our findings highlight the phenotypic partitioning of wing morphology and development in the parasitoid S. pupariae under varied environmental cues and reveal the most favourable conditions for the production of winged females in this bethylid wasp. It is thus possible to increase winged female parasitoid production for the purposes of biological control by manipulation of biotic and abiotic conditions.
When your pain signifies my gain: neural activity while evaluating outcomes based on another person’s pain
Authors: Cui Fang , Zhu Xiangru , Gu Ruolei , Luo Yue-jia
Published: May 2016

The overlap between pain and reward processing pathways leds researchers to hypothesize that there are interactions between them in the human brain. Two hypotheses have been proposed. The “competition hypothesis” posits that reward can reduce pain-related neural activity andvice versa. The “salience hypothesis” suggests that the motivational salience of pain and reward can be mutually reinforced. However, no study has tested these two hypotheses from temporal perspective as we know. In the present study, pictures depicted other people in painful or non-painful situations were used to indicate the valence of outcomes in a gambling task. The event-related potential results revealed an interaction between another person’s pain and outcome valence in multiple time stages. Specifically, the amplitudes of the N1 and P3 were enhanced in the win condition compared with the loss condition when the outcome was indicated by painful picture. This interactions between pain and reward support the salience hypothesis but not the competition hypothesis. The present results provide evidence from human subjects that support the salience hypothesis, which claims that observing other people’s pain can enhance the salience of reward.
The cytosolic Fe-S cluster assembly component MET18 is required for the full enzymatic activity of ROS1 in active DNA demethylation
Authors: Wang Xiaokang , Li Qi , Yuan Wei , Cao Zhendong , Qi Bei , Kumar Suresh , Li Yan , Qian Weiqiang
Published: May 2016

DNA methylation patterns in plants are dynamically regulated by DNA methylation and active DNA demethylation in response to both environmental changes and development of plant. Beginning with the removal of methylated cytosine by ROS1/DME family of 5-methylcytosine DNA glycosylases, active DNA demethylation in plants occurs through base excision repair. So far, many components involved in active DNA demethylation remain undiscovered. Through a forward genetic screening of Arabidopsis mutants showing DNA hypermethylation at the EPF2 promoter region, we identified the conserved iron-sulfur cluster assembly protein MET18. MET18 dysfunction caused DNA hypermethylation at more than 1000 loci as well as the silencing of reporter genes and some endogenous genes. MET18 can directly interact with ROS1 in vitro and in vivo. ROS1 activity was reduced in the met18 mutant plants and point mutation in the conserved Fe-S cluster binding motif of ROS1 disrupted its biological function. Interestingly, a large number of DNA hypomethylated loci, especially in the CHH context, were identified from the met18 mutants and most of the hypo-DMRs were from TE regions. Our results suggest that MET18 can regulate both active DNA demethylation and DNA methylation pathways in Arabidopsis.
Optical and electrochemical detection of biothiols based on aggregation of silver nanoparticles
Authors: Hu Lanshuang , Hu Shengqiang , Guo Linyan , Tang Ting , Yang Minghui
Published: May 2016

Optical and electrochemical detection of biothiols based on aggregation of individual sensing elements.
Catalyst-controlled switch of regioselectivity in the asymmetric allylic alkylation of oxazolones with MBHCs
Authors: Zhu Gongming , Yang Junxian , Bao Guangjun , Zhang Ming , Li Jing , Li Yiping , Sun Wangsheng , Hong Liang , Wang Rui
Published: May 2016

A catalyst-controlled switch of regioselectivity in asymmetric allylic alkylation of oxazolones with MBHCs was described.
Contrasting 1D tunnel-structured and 2D layered polymorphs of V2O5: relating crystal structure and bonding to band gaps and electronic structure
Authors: Tolhurst Thomas M. , Leedahl Brett , Andrews Justin L. , Marley Peter M. , Banerjee Sarbajit , Moewes Alexander
Published: May 2016

An elucidation of structure–property relationships in V2O5polymorphs using synchrotron X-ray spectroscopy and density functional theory calculations.
Thermally reversible full color selective reflection in a self-organized helical superstructure enabled by a bent-core oligomesogen exhibiting a twist-bend nematic phase
Authors: Wang Yuan , Zheng Zhi-gang , Bisoyi Hari Krishna , Gutierrez-Cuevas Karla G. , Wang Ling , Zola Rafael S. , Li Quan
Published: May 2016

A self-organized helical superstructure exhibits thermally reversible full color reflection upon doping a bent-core oligomesogen possessing a twist-bend nematic phase.
Diastereoselective synthesis of spiro[indene-2,2′-pyrazolo[1,2-a]pyrazoles] and spiro[indoline-3,2′-pyrazolo[1,2-a]pyrazoles] via 1,3-dipolar cycloaddition
Authors: Lu Yu-Ling , Sun Jing , Jiang Yan-Hong , Yan Chao-Guo
Published: May 2016

The 1,3-dipolar cycloaddition of cyclic azomethine imines with 2-arylideneindene-1,3-diones in refluxing acetonitrile afforded predominatelycis-1,3-diaryl-substituted spiro[indene-2,2′-pyrazolo[1,2-a]pyrazole] derivatives in good yields.
A versatile large-scale and green process for synthesizing magnetic nanoparticles with tunable magnetic hyperthermia features
Authors: Simeonidis K. , Liébana-Viñas S. , Wiedwald U. , Ma Z. , Li Z.-A. , Spasova M. , Patsia O. , Myrovali E. , Makridis A. , Sakellari D. , Tsiaoussis I. , Vourlias G. , Farle M. , Angelakeris M.
Published: May 2016

Production of functionalized nanoparticles for magnetic hyperthermia by an industrial-scale process.
Transport properties of Co-based Heusler compounds Co2VAl and Co2VGa: spin-polarized DFT+U
Authors: Reshak A. H.
Published: May 2016

The transport properties of Co2VAl and Co2VGa were calculated based on the calculated spin-polarized electronic band structures using the semi-classical Boltzmann theory as incorporated in BoltzTraP.
A thermo- and pH-responsive poly(N-isopropylacrylamide)–Mn–ZnS nanocomposite for controlled release and real-time photoluminescence tracking of doxorubicin
Authors: Wang Ruo-Mei , Liu Qian , Zhang Yu , Hong Zhangyong , Wang He-Fang
Published: May 2016

A novel multifunctional poly(N-isopropylacrylamide)–Mn–ZnS (PMZS) nanocomposite was developed as a smart drug carrier for thermo- and pH-controlled release of doxorubicin (Dox) and real-time photoluminescence tracking of the released Dox.
A trap-assisted ultrasensitive near-infrared organic photomultiple photodetector based on Y-type titanylphthalocyanine nanoparticles
Authors: Li Xiaolong , Wang Shirong , Xiao Yin , Li Xianggao
Published: May 2016

An ultrasensitive near-infrared organic photodetector with an EQE of 354 200% and a photoresponsivity of 2227 A W−1 has been fabricated by dip-coating.
Modelling and control of a novel zero‐current‐switching inverter with sinusoidal current output
Authors: Liu Wei , Zhang Jiasheng , Chen Rong
Published: May 2016

This study presents a novel topology of charge‐transferring zero‐current‐switching (CT‐ZCS) inverter to improve the efficiency. Its operating principle, optimal zero‐current‐switching (ZCS) frequency and design guidelines are elucidated in detail. A reduced‐order modelling method of time‐charge discretisation, which treats a set of two separate ZCS as one combined switch cell, is put forward and the topology can be simplified to dual‐buck half‐bridge inverter (DBHBI) topology. Since the DBHBI‐derived CT‐ZCS inverter permits higher comparison frequency of hysteresis control than traditional hard‐switching inverters, the three‐level relay control with high‐frequency pulse modulation is recommended. Compared with two‐level and three‐level hysteresis control, the proposed control can achieve effective output harmonic reduction, decreasing from 2.335 to 1.66%, and minimise the size of inverter under the same output condition. In addition, a current controller is designed to optimise the system and enhance its anti‐disturbance performance. Finally, the experiment on a 35‐V 2‐A prototype verifies the validity of the proposed method.
Development of a low noise induction magnetic sensor using magnetic flux negative feedback in the time domain
Authors: Wang X. G. , Shang X. L. , Lin J.
Published: May 2016

Time-domain electromagnetic system can implement great depth detection. As for the electromagnetic system, the receiver utilized an air coil sensor, and the matching mode of the sensor employed the resistance matching method. By using the resistance matching method, the vibration of the coil in the time domain can be effectively controlled. However, the noise of the sensor, especially the noise at the resonance frequency, will be increased as well. In this paper, a novel design of a low noise induction coil sensor is proposed, and the experimental data and noise characteristics are provided. The sensor is designed based on the principle that the amplified voltage will be converted to current under the influence of the feedback resistance of the coil. The feedback loop around the induction coil exerts a magnetic field and sends the negative feedback signal to the sensor. The paper analyses the influence of the closed magnetic feedback loop on both the bandwidth and the noise of the sensor. The signal-to-noise ratio is improved dramatically.
Optical pseudomotors for soft x-ray beamlines
Authors: Pedreira P. , Sics I. , Sorrentino A. , Pereiro E. , Aballe L. , Foerster M. , Pérez-Dieste V. , Escudero C. , Nicolas J.
Published: May 2016

Optical elements of soft x-ray beamlines usually have motorized translations and rotations that allow for the fine alignment of the beamline. This is to steer the photon beam at some positions and to correct the focus on slits or on sample. Generally, each degree of freedom of a mirror induces a change of several parameters of the beam. Inversely, several motions are required to actuate on a single optical parameter, keeping the others unchanged. We define optical pseudomotors as combinations of physical motions of the optical elements of a beamline, which allow modifying one optical parameter without affecting the others. We describe a method to obtain analytic relationships between physical motions of mirrors and the corresponding variations of the beam parameters. This method has been implemented and tested at two beamlines at ALBA, where it is used to control the focus of the photon beam and its position independently.
On the correct implementation of Fermi–Dirac statistics and electron trapping in nonlinear electrostatic plane wave propagation in collisionless plasmas
Authors: Schamel Hans , Eliasson Bengt
Published: May 2016

Quantum statistics and electron trapping have a decisive influence on the propagation characteristics of coherent stationary electrostatic waves. The description of these strictly nonlinear structures, which are of electron hole type and violate linear Vlasov theory due to the particle trapping at any excitation amplitude, is obtained by a correct reduction of the three-dimensional Fermi-Dirac distribution function to one dimension and by a proper incorporation of trapping. For small but finite amplitudes, the holes become of cnoidal wave type and the electron density is shown to be described by a ϕ(x)1/2 rather than a ϕ(x) expansion, where ϕ(x) is the electrostatic potential. The general coefficients are presented for a degenerate plasma as well as the quantum statistical analogue to these steady state coherent structures, including the shape of ϕ(x) and the nonlinear dispersion relation, which describes their phase velocity.
Wave propagation in reconfigurable broadband gain metamaterials at microwave frequencies
Authors: Fan Yifeng , Nagarkoti Deepak S. , Rajab Khalid Z. , Hao Yang , Zhang Hao Chi , Cui Tie Jun
Published: May 2016

The wave dispersion characteristics for loop array-based metamaterials were analyzed, based on the general transmission line model of a one-dimensional host medium interacting with a chain of coupled loops. By relating the wave propagation constant and the effective parameters of the coupled host medium, we showed that an active medium embedded with non-Foster loaded loop array can be designed to exhibit broadband negative material parameters with positive gain. Accounting for all interactions, the stability of the active medium was investigated, further yielding necessary design specifications for the non-Foster loads. Subsequently, an experimental demonstration was provided to verify the theoretical analysis, showing that stable reconfigurable broadband gain metamaterials at microwave frequencies can be obtained with proper negative impedance converter design.