bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and characterization of emamectin-benzoate slow-release microspheres with different surfactants
Authors: Wang Yan , Wang Anqi , Wang Chunxin , Cui Bo , Sun Changjiao , Zhao Xiang , Zeng Zhanghua , Shen Yue , Gao Fei , Liu Guoqiang , Cui Haixin
Published: October 2017

Pesticide slow-release formulations provide a way to increase the efficiency of active components by reducing the amount of pesticide that needs to be applied. Slow-release formulations also increase the stability and prolong the control effect of photosensitive pesticides. Surfactants are an indispensable part of pesticide formulations, and the choice of surfactant can strongly affect formulation performance. In this study, emamectin-benzoate (EMB) slow-release microspheres were prepared by the microemulsion polymerization method. We explored the effect of different surfactants on the particle size and dispersity of EMB in slow-release microspheres. The results indicated that the samples had uniform spherical shapes with an average diameter of 320.5 ±5.24 nm and good dispersity in the optimal formulation with the polymeric stabilizer polyvinyl alcohol (PVA) and composite non-ionic surfactant polyoxyethylene castor oil (EL-﻿40). The optimal EMB pesticide slow-release microspheres had excellent anti-photolysis performance, stability, controlled release properties, and good leaf distribution. These results demonstrated that EMB slow-release microspheres are an attractive candidate for improving pesticide efficacy and prolonging the control effect of EMB in the environment.
Behavior of human periodontal ligament cells on dentin surfaces ablated with an ultra-short pulsed laser
Authors: Liu Jing , Andrukhov Oleh , Laky Markus , Nürnberger Sylvia , Moritz Andreas , Lyu Peijun , Rausch-Fan Xiaohui
Published: October 2017

This study aimed to evaluate the effects of an ultrashort pulsed laser (USPL) (1064 nm, 20 ps, 100 kHz) with different laser fluences (F, 4, 6, 8 J/cm2) and pulse overlaps (PO, 0, 50%) on human periodontal ligament cells (hPDLs) behavior. Dentin samples were ablated with USPL with different combinations of fluences and pulse overlaps; some samples were ablated with an Er:YAG laser (2940 nm, 150 µs, 100 mJ/pulse, 5 J/cm2) and some samples were ground with a carbide bur. Then hPDLs were grown on the samples after different treatments. Dentin morphology and cell adhesion were observed with SEM and gene expressions were measured by RT-PCR. The results showed dentin surfaces ablated with USPL when F = 4 J/cm2, PO = 0, and F = 6 J/cm2, PO = 0 were partially intact with obvious ridges and valleys and cells on these surfaces grew mostly along the valleys. USPL ablated surfaces in other groups were entirely ablated and cell cluster formation was observed. The RT-PCR results showed an upregulation of osteocalcin of cells grown on the dentin after some laser treatment. It can be concluded that USPL could improve the attachment and differentiation of hPDLs and thus potentially promote periodontal tissue regeneration.
Algorithm guided outlining of 105 pancreatic cancer liver metastases in Ultrasound
Authors: Hann Alexander , Bettac Lucas , Haenle Mark M. , Graeter Tilmann , Berger Andreas W. , Dreyhaupt Jens , Schmalstieg Dieter , Zoller Wolfram G. , Egger Jan
Published: October 2017

Manual segmentation of hepatic metastases in ultrasound images acquired from patients suffering from pancreatic cancer is common practice. Semiautomatic measurements promising assistance in this process are often assessed using a small number of lesions performed by examiners who already know the algorithm. In this work, we present the application of an algorithm for the segmentation of liver metastases due to pancreatic cancer using a set of 105 different images of metastases. The algorithm and the two examiners had never assessed the images before. The examiners first performed a manual segmentation and, after five weeks, a semiautomatic segmentation using the algorithm. They were satisfied in up to 90% of the cases with the semiautomatic segmentation results. Using the algorithm was significantly faster and resulted in a median Dice similarity score of over 80%. Estimation of the inter-operator variability by using the intra class correlation coefficient was good with 0.8. In conclusion, the algorithm facilitates fast and accurate segmentation of liver metastases, comparable to the current gold standard of manual segmentation.
Enhancing excitatory activity of somatosensory cortex alleviates neuropathic pain through regulating homeostatic plasticity
Authors: Xiong Wenhui , Ping Xingjie , Ripsch Matthew S. , Chavez Grace Santa Cruz , Hannon Heidi Elise , Jiang Kewen , Bao Chunhui , Jadhav Vaishnavi , Chen Lifang , Chai Zhi , Ma Cungen , Wu Huangan , Feng Jianqiao , Blesch Armin , White Fletcher A. , Jin Xiaoming
Published: October 2017

Central sensitization and network hyperexcitability of the nociceptive system is a basic mechanism of neuropathic pain. We hypothesize that development of cortical hyperexcitability underlying neuropathic pain may involve homeostatic plasticity in response to lesion-induced somatosensory deprivation and activity loss, and can be controlled by enhancing cortical activity. In a mouse model of neuropathic pain, in vivo two-photon imaging and patch clamp recording showed initial loss and subsequent recovery and enhancement of spontaneous firings of somatosensory cortical pyramidal neurons. Unilateral optogenetic stimulation of cortical pyramidal neurons both prevented and reduced pain-like behavior as detected by bilateral mechanical hypersensitivity of hindlimbs, but corpus callosotomy eliminated the analgesic effect that was ipsilateral, but not contralateral, to optogenetic stimulation, suggesting involvement of inter-hemispheric excitatory drive in this effect. Enhancing activity by focally blocking cortical GABAergic inhibition had a similar relieving effect on the pain-like behavior. Patch clamp recordings from layer V pyramidal neurons showed that optogenetic stimulation normalized cortical hyperexcitability through changing neuronal membrane properties and reducing frequency of excitatory postsynaptic events. We conclude that development of neuropathic pain involves abnormal homeostatic activity regulation of somatosensory cortex, and that enhancing cortical excitatory activity may be a novel strategy for preventing and controlling neuropathic pain.
Dynamics of functional connectivity at high spatial resolution reveal long-range interactions and fine-scale organization
Authors: Preti Maria Giulia , Van De Ville Dimitri
Published: October 2017

Dynamic functional connectivity (dFC) derived from resting-state functional magnetic resonance imaging sheds light onto moment-to-moment reconfigurations of large-scale functional brain networks. Due to computational limits, connectivity is typically computed using pre-defined atlases, a non-trivial choice that might influence results. Here, we leverage new computational methods to retrieve dFC at the voxel level in terms of dominant patterns of fluctuations, and demonstrate that this new representation is informative to derive meaningful brain parcellations, capturing both long-range interactions and fine-scale local organization. Specifically, voxelwise dFC dominant patterns were captured through eigenvector centrality followed by clustering across time/subjects to yield most representative dominant patterns (RDPs). Voxel-wise labeling according to positive/negative contributions to RDPs, led to 37 unique labels identifying strikingly symmetric dFC long-range patterns. These included 449 contiguous regions, defining a fine-scale parcellation consistent with known cortical/subcortical subdivisions. Our contribution provides an alternative to obtain a whole-brain parcellation that is for the first time driven by voxel-level dFC and bridges the gap between voxel-based approaches and graph theoretical analysis.
Activin in acute pancreatitis: Potential risk-stratifying marker and novel therapeutic target
Authors: Staudacher Jonas J. , Yazici Cemal , Carroll Timothy , Bauer Jessica , Pang Jingbo , Krett Nancy , Xia Yinglin , Wilson Annette , Papachristou Georgios , Dirmeier Andrea , Kunst Claudia , Whitcomb David C. , Fantuzzi Giamila , Jung Barbara
Published: October 2017

Acute Pancreatitis is a substantial health care challenge with increasing incidence. Patients who develop severe disease have considerable mortality. Currently, no reliable predictive marker to identify patients at risk for severe disease exists. Treatment is limited to rehydration and supporting care suggesting an urgent need to develop novel approaches to improve standard care. Activin is a critical modulator of inflammatory responses, but has not been assessed in pancreatitis. Here, we demonstrate that serum activin is elevated and strongly correlates with disease severity in two established murine models of acute pancreatitis induced by either cerulein or IL-12 + IL-18. Furthermore, in mice, inhibition of activin conveys survival benefits in pancreatitis. In addition, serum activin levels were measured from a retrospective clinical cohort of pancreatitis patients and high activin levels in patients at admission are predictive of worse outcomes, indicated by longer overall hospital and intensive care unit stays. Taken together, activin is a novel candidate as a clinical marker to identify those acute pancreatitis patients with severe disease who would benefit from aggressive treatment and activin may be a therapeutic target in severe acute pancreatitis.
Antireflection coating of barriers to enhance electron tunnelling: exploring the matter wave analogy of superluminal optical phase velocity
Authors: Zhao Zijun C. , McKenzie David R.
Published: October 2017

The tunnelling of electrons through barriers is important in field emission sources and in interconnects within electronic devices. Here we use the analogy between the electromagnetic wave equation and the Schrodinger equation to find potential barriers that, when added before an existing barrier, increase the transmission probability. A single pre-barrier of negative potential behaves as a dielectric “antireflection coating”, as previously reported. However, we obtain an unexpected and much greater enhancement of transmission when the pre-barrier has a positive potential of height smaller than the energy of the incident electron, an unfamiliar optical case, corresponding to media with superluminal phase velocities as in dilute free electron media and anomalous dispersion at X-ray frequencies. We use a finite difference time domain algorithm to evaluate the transmission through a triangular field emission barrier with a pre-barrier that meets the new condition. We show that the transmission is enhanced for an incident wavepacket, producing a larger field emission current than for an uncoated barrier. Examples are given of available materials to enhance transmission in practical applications. The results are significant for showing how to increase electron transmission in field emission and at interconnects between dissimilar materials in all types of electronic devices.
Clinical implication of ectopic liver lipid accumulation in renal cell carcinoma patients without visceral obesity
Authors: Watanabe Daisuke , Horiguchi Akio , Tasaki Shinsuke , Kuroda Kenji , Sato Akinori , Asakuma Junichi , Ito Keiichi , Asano Tomohiko , Shinmoto Hiroshi
Published: October 2017

Fatty liver has emerged as a prognostic marker of cancer, so we investigated the impact of ectopic lipid accumulation in liver on the clinical outcome for patients with renal cell carcinoma (RCC). The records of 230 consecutive patients who had undergone surgery for RCC were reviewed, and liver lipid accumulation was estimated from the attenuation in unenhanced preoperative CT images. The median liver CT values of patients with G3 tumors was lower than that of patients with G1–2 tumors (P = 0.0116), that of patients with pT3–4 tumors was lower than that of patients with pT1–2 tumors (P = 0.0336), and that of patients with visceral obesity defined as a visceral fat area ≥ 100 cm2 was lower than that of patients without visceral obesity (P < 0.0001). In patients without visceral obesity the median liver CT values of patients with pT3–4 tumors was lower than that of patients with pT1–2 tumors (P = 0.0401), that of patients with metastasis was lower than that of patients without metastasis (P = 0.026), and fatty liver was associated with shorter overall survival (P = 0.0009). Ectopic lipid accumulation in liver thus seems to be a predictor of aggressive forms of RCC.
Nanoscale patterning of self-assembled monolayer (SAM)-functionalised substrates with single molecule contact printing
Authors: Sajfutdinow M. , Uhlig K. , Prager A. , Schneider C. , Abel B. , Smith D. M.
Published: October 2017

DNA origami stamps print biomolecules onto SAM-coated gold filmsviabioconjugation in a process called single molecule contact printing.
Enhanced near room temperature magnetocaloric effect in La0.6Ca0.4MnO3 for magnetic refrigeration application
Authors: Tsui Melissa H. M. , Dryer Devon T. , El-Gendy Ahmed A. , Carpenter Everett E.
Published: October 2017

Perovskite manganite La0.6Ca0.4MnO3 (LCMO) nanomaterials were synthesized by a modified Pechini sol–gel process followed by high temperature sintering.
Significantly improved cyclability of lithium manganese oxide, simultaneously inhibiting electrochemical and thermal decomposition of the electrolyte by the use of an additive
Authors: Liao Bo , Li Hongying , Wang Xianshu , Xu Mengqing , Xing Lidan , Liao Youhao , Liu Xiang , Li Weishan
Published: October 2017

4-(Trifluoromethyl)benzonitrile (4-TB) can help form a protective interphase film on LiMn2O4 and improves the thermal stability of the electrolyte.
A new layered titanate Na2Li2Ti5O12as a high-performance intercalation anode for sodium-ion batteries
Authors: Huang Yangyang , Wang Jinsong , Miao Lin , Jin Yu , Peng Jian , Li Qing , Fang Chun , Han Jiantao , Huang Yunhui
Published: October 2017

As a new anode material for sodium-ion battery, layered sodium titanium oxide Na2Li2Ti5O12shows large capacity, long cycle life and especially fast-charging performance, which is promising for future application.
Functionally graded and homogeneous composites of La2NiO4+δ and Lan+1NinO3n+1 (n = 2 and 3) solid oxide fuel cell cathodes
Authors: Sharma R. K. , Djurado E.
Published: October 2017

Functionally graded composite cathodes based on Ruddlesden–Popper phases show better electrical performance than homogeneous ones.
MOF derived ZnCo2O4 porous hollow spheres functionalized with Ag nanoparticles for a long-cycle and high-capacity lithium ion battery anode
Authors: Koo Won-Tae , Jang Hye-Yeon , Kim Chanhoon , Jung Ji-Won , Cheong Jun Young , Kim Il-Doo
Published: October 2017

Ag nanoparticle-decorated ZnCo2O4 hollow spheres are synthesized by using MOF templates and an Ag-mirror reaction, for high-performance lithium-ion battery anode materials.
Zinc ion mediated synthesis of cuprous oxide crystals for non-enzymatic glucose detection
Authors: Lv Jian , Kong Chuncai , Hu Xuanxuan , Zhang Xiaojing , Liu Ke , Yang Shengchun , Bi Jinglei , Liu Xiaoyan , Meng Ge , Li Jianhui , Yang Zhimao , Yang Sen
Published: October 2017

Zn2+was used to mediate the fabrication of Cu2O crystals with different glucose sensing performances depending on their structures.
InP/ZnSe/ZnS quantum dots with strong dual emissions: visible excitonic emission and near-infrared surface defect emission and their application in in vitro and in vivo bioimaging
Authors: Zhang Jie , Wang Jie , Yan Tong , Peng Yanan , Xu Dajun , Deng Dawei
Published: October 2017

Unique oil-soluble InP/ZnSe/ZnS QDs with strong visible excitonic and NIR surface defect emissions were synthesized and used in multi-scale bioimaging.
A transparent 3D electrode with a criss-crossed nanofiber network for solid electrochromic devices
Authors: Yang Guojian , Guan Dehui , Wang Nan , Zhang Weiran , Gu Chang , Zhang Yu-Mo , Li Minjie , Zhang Sean Xiao-An
Published: October 2017

An ideal transparent 3D electrode capable of increasing the response rate and decreasing the diffusion distance of charge for solid electrochromic devices was fabricated by the combination of ITO nanofibers and an FTO electrode.
A thermal-sensitizing and thermochromic phosphor
Authors: Tang Xue , Li Xiaodong , Zou Zehua , Ma Zhidong , Zhang Jiachi , Wang Zhaofeng , Ci Zhipeng , Wang Deyin , Peng Shanglong , Li Huihui , Wang Yuhua
Published: October 2017

Phosphors are efficient luminescent materials that are being extensively used in lighting and displays in today's world.
Direct visualization of interaction between calmodulin and connexin45
Authors: Zou Juan , Salarian Mani , Chen Yanyi , Zhuo You , Brown Nicole E. , Hepler John R. , Yang Jenny J.
Published: September 2017

Calmodulin (CaM) is an intracellular Ca2+ transducer involved in numerous activities in a broad Ca2+ signaling network. Previous studies have suggested that the Ca2+/CaM complex may participate in gap junction regulation via interaction with putative CaM-binding motifs in connexins; however, evidence of direct interactions between CaM and connexins has remained elusive to date due to challenges related to the study of membrane proteins. Here, we report the first direct interaction of CaM with Cx45 (connexin45) of γ-family in living cells under physiological conditions by monitoring bioluminescence resonance energy transfer. The interaction between CaM and Cx45 in cells is strongly dependent on intracellular Ca2+ concentration and can be blocked by the CaM inhibitor, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride (W7). We further reveal a CaM-binding site at the cytosolic loop (residues 164–186) of Cx45 using a peptide model. The strong binding (Kd ∼ 5 nM) observed between CaM and Cx45 peptide, monitored by fluorescence-labeled CaM, is found to be Ca2+-dependent. Furthermore, high-resolution nuclear magnetic resonance spectroscopy reveals that CaM and Cx45 peptide binding leads to global chemical shift changes of 15N-labeled CaM, but does not alter the size of the structure. Observations involving both N- and C-domains of CaM to interact with the Cx45 peptide differ from the embraced interaction with Cx50 from another connexin family. Such interaction further increases Ca2+ sensitivity of CaM, especially at the N-terminal domain. Results of the present study suggest that both helicity and the interaction mode of the cytosolic loop are likely to contribute to CaM's modulation of connexins.
Onconase dimerization through 3D domain swapping: structural investigations and increase in the apoptotic effect in cancer cells
Authors: Fagagnini Andrea , Pica Andrea , Fasoli Sabrina , Montioli Riccardo , Donadelli Massimo , Cordani Marco , Butturini Elena , Acquasaliente Laura , Picone Delia , Gotte Giovanni
Published: September 2017

Onconase® (ONC), a protein extracted from the oocytes of the Rana pipiens frog, is a monomeric member of the secretory ‘pancreatic-type’ RNase superfamily. Interestingly, ONC is the only monomeric ribonuclease endowed with a high cytotoxic activity. In contrast with other monomeric RNases, ONC displays a high cytotoxic activity. In this work, we found that ONC spontaneously forms dimeric traces and that the dimer amount increases about four times after lyophilization from acetic acid solutions. Differently from RNase A (bovine pancreatic ribonuclease) and the bovine seminal ribonuclease, which produce N- and C-terminal domain-swapped conformers, ONC forms only one dimer, here named ONC-D. Cross-linking with divinylsulfone reveals that this dimer forms through the three-dimensional domain swapping of its N-termini, being the C-terminus blocked by a disulfide bond. Also, a homology model is proposed for ONC-D, starting from the well-known structure of RNase A N-swapped dimer and taking into account the results obtained from spectroscopic and stability analyses. Finally, we show that ONC is more cytotoxic and exerts a higher apoptotic effect in its dimeric rather than in its monomeric form, either when administered alone or when accompanied by the chemotherapeutic drug gemcitabine. These results suggest new promising implications in cancer treatment.
Sequencing of chondroitin sulfate oligosaccharides using a novel exolyase from a marine bacterium that degrades hyaluronan and chondroitin sulfate/dermatan sulfate
Authors: Wang Wenshuang , Cai Xiaojuan , Han Naihan , Han Wenjun , Sugahara Kazuyuki , Li Fuchuan
Published: September 2017

Glycosaminoglycans (GAGs) are a family of chemically heterogeneous polysaccharides that play important roles in physiological and pathological processes. Owing to the structural complexity of GAGs, their sophisticated chemical structures and biological functions have not been extensively studied. Lyases that cleave GAGs are important tools for structural analysis. Although various GAG lyases have been identified, exolytic lyases with unique enzymatic property are urgently needed for GAG sequencing. In the present study, a putative exolytic GAG lyase from a marine bacterium was recombinantly expressed and characterized in detail. Since it showed exolytic lyase activity toward hyaluronan (HA), chondroitin sulfate (CS), and dermatan sulfate (DS), it was designated as HCDLase. This novel exolyase exhibited the highest activity in Tris–HCl buffer (pH 7.0) at 30°C. Especially, it showed a specific activity that released 2-aminobenzamide (2-AB)-labeled disaccharides from the reducing end of 2-AB-labeled CS oligosaccharides, which suggest that HCDLase is not only a novel exolytic lyase that can split disaccharide residues from the reducing termini of sugar chains but also a useful tool for the sequencing of CS chains. Notably, HCDLase could not digest 2-AB-labeled oligosaccharides from HA, DS, or unsulfated chondroitin, which indicated that sulfates and bond types affect the catalytic activity of HCDLase. Finally, this enzyme combined with CSase ABC was successfully applied for the sequencing of several CS hexa- and octasaccharides with complex structures. The identification of HCDLase provides a useful tool for CS-related research and applications.
Expression correlates between Annexin A1 and A2 autoantibodies in patients with Behçet’s disease
Authors: Hussain Muhammad , Chen Peng , Mei Guang , Li Yongzhe , Du Hongwu
Published: September 2017

The autoantibodies profile of Behçet’s disease (BD) is yet incompletely understood. Annexins are a family of highly conserved proteins which are involved in some human autoimmune diseases. Autoantibodies directed toward Annexin A1 and A2 are involved in BD pathology, but correlation in their clinical role is controversial. The aim of our study is to estimate and evaluate the expression correlation between Annexin A1 and A2 autoantibodies in BD patients. We have designed and implemented different technical approaches to prove the hypothesis. First, bioinformatics tools such as amino acid sequence alignment, epitope prediction analysis, and 3D structural comparison were performed to find out the correlation between Annexin A1 and A2. Second, amplification of the corresponding gene by RT-PCR, then cloning, and purification techniques were applied to acquire the recombinant Annexin A1. Third, the target protein band was excised from gel electrophoresis, digested with trypsin, and analyzed by MALDI-TOF/TOF. Finally, in-house ELISA was developed to determine the induced anti-Annexin A1 autoantibodies in BD patients. Obtained results demonstrated that the BD serum reactivity against recombinant Annexin A1 was significantly higher as compared with healthy control (HC) (P<0.001). Moreover, bioassay results of Annexin A1 and A2 also showed the presence, absence, and independent coexistence of autoantibodies, when reacted with BD sera. In conclusion, Annexin A1 has a similar immunogenic expression and correlation with its analog Annexin A2 and their association may be a novel immune target of BD in Han Chinese population.
Animal models of cerebral amyloid angiopathy
Authors: Jäkel Lieke , Van Nostrand William E. , Nicoll James A.R. , Werring David J. , Verbeek Marcel M.
Published: September 2017

Cerebral amyloid angiopathy (CAA), due to vascular amyloid β (Aβ) deposition, is a risk factor for intracerebral haemorrhage and dementia. CAA can occur in sporadic or rare hereditary forms, and is almost invariably associated with Alzheimer’s disease (AD). Experimental (animal) models are of great interest in studying mechanisms and potential treatments for CAA. Naturally occurring animal models of CAA exist, including cats, dogs and non-human primates, which can be used for longitudinal studies. However, due to ethical considerations and low throughput of these models, other animal models are more favourable for research. In the past two decades, a variety of transgenic mouse models expressing the human Aβ precursor protein (APP) has been developed. Many of these mouse models develop CAA in addition to senile plaques, whereas some of these models were generated specifically to study CAA. In addition, other animal models make use of a second stimulus, such as hypoperfusion or hyperhomocysteinemia (HHcy), to accelerate CAA. In this manuscript, we provide a comprehensive review of existing animal models for CAA, which can aid in understanding the pathophysiology of CAA and explore the response to potential therapies.
High‐gain and power‐efficient dynamic amplifier for pipelined SAR ADCs
Authors: Lyu Y. , Ramkaj A. , Tavernier F.
Published: September 2017

A new power‐efficient dynamic residue amplifier for pipelined successive‐approximation‐register (SAR) ADCs is presented. A complementary input pair and a reference level detection technique are proposed to improve the performance of the dynamic amplifier. At a 400 MS/s sampling rate, the proposed amplifier achieves a gain of 16. The input referred noise is 57.2 μV and the total harmonic distortion is –57.1 dB. The power consumption of the proposed amplifier is 55.6 μW in 28 nm CMOS technology.
Pattern reconfigurable ESPAR antenna for vehicle‐to‐vehicle communications
Authors: Marantis Leonidas , Rongas Dimitrios , Paraskevopoulos Anastasios , Oikonomopoulos‐Zachos Christos , Kanatas Athanasios
Published: September 2017

This study proposes an electronically switched parasitic array radiator (ESPAR) antenna at 5.9 GHz to meet the intelligent transportation systems standards. This antenna offers pattern switching capability with three distinct radiation patterns, i.e. one quasi‐omni and two directives in opposite directions, by controlling the mutual coupling at the parasitic elements with PIN diode switches. A considerable gain increase of up to 3 dB is achieved in the directive mode, while maintaining a satisfying impedance matching between the switching states. The compact ESPAR antenna is printed on a low loss Rogers dielectric and consists of one active and two parasitic monopoles. S11 and radiation pattern results are presented, derived from both simulations and measurements, exhibiting a close agreement.
Review on DC collection grids for offshore wind farms with high‐voltage DC transmission system
Authors: Musasa Kabeya , Nwulu Nnamdi I. , Gitau Michael N. , Bansal Ramesh C.
Published: September 2017

Traditionally, the network composition of offshore wind farms consists of alternating current (AC) grid; all outputs of wind‐energy conversion units (WECUs) on a wind farm are aggregated to an AC bus. Each WECU includes: a wind‐turbine (WT), a generator and a power transformer. For a DC collection grid, all outputs of WECUs are aggregated to a DC bus. The transformer in each WECU is replaced by a converter which is more compact and smaller in size compared with the transformer, thus simplifying the wind farm structure. The use of AC offshore grids instead of DC offshore grids is mainly motivated by the availability of protection devices. Efficient solutions to protect DC grids have already been addressed. Presently, there are no operational DC wind‐farms, only small‐scale prototypes are being investigated worldwide. Therefore, a suitable configuration of the DC collection grid, which has been practically verified, is not available yet. This study discussed some of the main components required for a DC grid including: the WT‐generator models, the control and protection methods, the platform structure, and the feeder configurations. The key component of a DC grid is the converter; therefore, this study also reviews some topologies of converter suitable for DC‐grid applications.
MINERVA: A facility to study Microstructure and INterface Evolution in Realtime under VAcuum
Authors: Nicklin Chris , Martinez-Hardigree Josue , Warne Adam , Green Stephen , Burt Martin , Naylor John , Dorman Adam , Wicks Dean , Din Salahud , Riede Moritz
Published: October 2017

A sample environment to enable real-time X-ray scattering measurements to be recorded during the growth of materials by thermal evaporation in vacuum is presented. The in situ capabilities include studying microstructure development with time or during exposure to different environmental conditions, such as temperature and gas pressure. The chamber provides internal slits and a beam stop, to reduce the background scattering from the X-rays passing through the entrance and exit windows, together with highly controllable flux rates of the evaporants. Initial experiments demonstrate some of the possibilities by monitoring the growth of bathophenanthroline (BPhen), a common molecule used in organic solar cells and organic light emitting diodes, including the development of the microstructure with time and depth within the film. The results show how BPhen nanocrystal structures coarsen at room temperature under vacuum, highlighting the importance of using real time measurements to understand the as-deposited pristine film structure and its development with time. More generally, this sample environment is versatile and can be used for investigation of structure-property relationships in a wide range of vacuum deposited materials and their applications in, for example, optoelectronic devices and energy storage.
Magnetic anisotropy of L1-ordered FePt thin films studied by Fe and Pt L2,3-edges x-ray magnetic circular dichroism
Authors: Ikeda K. , Seki T. , Shibata G. , Kadono T. , Ishigami K. , Takahashi Y. , Horio M. , Sakamoto S. , Nonaka Y. , Sakamaki M. , Amemiya K. , Kawamura N. , Suzuki M. , Takanashi K. , Fujimori A.
Published: October 2017

The strong perpendicular magnetic anisotropy of L10-ordered FePt has been the subject of extensive studies for a long time. However, it is not known which element, Fe or Pt, mainly contributes to the magnetic anisotropy energy. We have investigated the anisotropy of the orbital magnetic moments of Fe 3d and Pt 5d electrons in L10-ordered FePt thin films by Fe and Pt L2,3-edge x-ray magnetic circular dichroism (XMCD) measurements for samples with various degrees of long-range chemical order S. Fe L2,3-edge XMCD showed that the orbital magnetic moment was larger when the magnetic field was applied perpendicular to the film than parallel to it and that the anisotropy of the orbital magnetic moment increased with S. Pt L2,3-edge XMCD also showed that the orbital magnetic moment was smaller when the magnetic field was applied perpendicular to the film than parallel to it, opposite to the Fe L2,3-edge XMCD results although the anisotropy of the orbital magnetic moment increases with S like the Fe edge. These results are qualitatively consistent with the first-principles calculation by Solovyev et al. [Phys. Rev. B 52, 13419 (1995)], which also predicts the dominant contributions of Pt 5d to the magnetic anisotropy energy rather than Fe 3d due to the strong spin-orbit coupling and the small spin splitting of the Pt 5d bands in L10-ordered FePt.
Hexagonal to monoclinic phase transformation in Eu2O3 thin films grown on GaN (0001)
Authors: Hadamek Tobias , Shin Donghan , Posadas Agham B. , Demkov Alexander A. , Kwon Sunah , Wang Qingxiao , Kim Moon
Published: October 2017

The high-pressure hexagonal phase of Eu2O3 has been grown epitaxially on C-plane GaN (0001) by molecular beam epitaxy. A structural phase transition from the hexagonal to the monoclinic phase is observed with increasing film thickness by ex-situ X-ray diffraction. The critical thickness for the structural transition is between 2 and 6 nm. The observed epitaxial relationships between the substrate and the film are GaN (0001) ǁ Eu2O3 (0001), GaN ⟨112¯0⟩ ǁ Eu2O3 ⟨112¯0⟩ for the hexagonal phase, and GaN (0001) ǁ Eu2O3 (201¯), GaN ⟨112¯0⟩ ǁ Eu2O3 [020] with six rotational domains for the monoclinic phase. The (0.8 ± 0.2) eV conduction band offset and bulk dielectric constant of ∼14 makes Eu2O3 a possible gate dielectric for a GaN-based field effect transistor.
On the optical performance of composite structures of graphene and photonic crystals at infrared wavelengths
Authors: Si Jizong , Sun Cheng
Published: October 2017

This work reports on a study regarding the optical performance of composite structures consisting of graphene and photonic crystals at infrared wavelengths. In the composite structures, single and/or multi-layer graphene are placed in between the alternating dielectric materials of the photonic crystals. The optical properties of the composite structures, including the light transmittance and reflectance, are numerically simulated in the infrared wavelength range from 1 to 100 μm, by varying the parameters associated with the graphene. The results reveal a band-gap feature below 6 μm, and a switch-like characteristics above 6 μm. The results also demonstrate that the optical properties of the composite structures can be tuned in the infrared regime, by adjusting the graphene parameters, including the Fermi energy levels and the layer numbers. Based on the optical performance revealed in this study, we suggest that the composite structures comprised of graphene and photonic crystals be implemented in future designs of plasmonic tuning devices at infrared wavelengths.
Nonlinear plasma waves driven by short ultrarelativistic electron bunches
Authors: Wang Tianhong , Khudik Vladimir , Breizman Boris , Shvets Gennady
Published: October 2017

We advance a theory of quasistatic approximation and investigate the excitation of nonlinear plasma waves by the driving beam of ultrarelativistic electrons using a novel electrostatic-like particle-in-cell code. Assuming that the beam occupies an infinitesimally small volume, we find the radius and the length of the plasma bubble formed in the wake of the driver for varying values of the beam charge. The mechanism of bubble formation is explained by developing simple models of the bubble at large charges. Plasma electrons expelled by the driver charge excite secondary plasma waves, which complicate the plasma electron flow near the bubble boundary.
Development of chorion-less zebrafish embryos in millifluidic living embryo arrays
Authors: Fuad Nurul Mohd , Kaslin Jan , Wlodkowic Donald
Published: October 2017

Dechorionation of zebrafish embryos has been proposed as a tool to improve toxicity bioassays because the chorion membrane forms a molecular barrier that can slow down or prevent chemicals from reaching the embryo. Despite its potential importance for experimental and predictive toxicology, the culture of dechorionated zebrafish embryos in a microfluidic environment has so far not received any attention. Here, we demonstrate a new Lab-on-a-Chip technology capable of automated, hydrodynamic immobilization of dechorionated embryos of Danio rerio. We show that chorion-less embryos can develop normally under microfluidic perfusion and be successfully used for on-chip developmental toxicity bioassays.
Kinetic features of collisionless sheaths around polarized cylindrical emitters from the orbital motion theory
Authors: Chen Xin , Sanchez-Arriaga G.
Published: October 2017

The kinetic features of the sheath around a cylindrical emitter immersed in collisionless plasma at rest are analysed. After finding self-consistently the electric potential by applying the Orbital Motion Theory to the Vlasov-Poisson system, the local distribution functions are reconstructed and the radial profiles of important macroscopic quantities (plasma densities, currents, and temperatures) are then computed. It is found that there can only be three kinds of holes that are bound by three different boundaries—two related to the constraints from orbital effects and the other due to the electric potential barrier. The results are presented for three regimes: negative probe bias with monotonic and non-monotonic potential and positive probe bias with non-monotonic potential. To understand the variation of macroscopic-quantity radial profiles, three diagrams are presented for kinetic features: the ϵl-diagram for the integration domains of the two orbital invariants, the effective potential, and the local distribution function. The envelope in the ϵl-diagram is crucial to identify different orbital behaviours, which can be used as a guideline for analytical analyses and serve as one of the criteria to refine the mesh used in numerical calculations.
Comparison of JET AVDE disruption data with M3D simulations and implications for ITER
Authors: Strauss H. , Joffrin E. , Riccardo V. , Breslau J. , Paccagnella R. ,   JET Contributors
Published: October 2017

Nonlinear 3D MHD asymmetric vertical displacement disruption simulations have been performed using JET equilibrium reconstruction initial data. Several experimentally measured quantities are compared with the simulation. These include vertical displacement, halo current, toroidal current asymmetry, and toroidal rotation. The experimental data and the simulations are in reasonable agreement. Also compared was the correlation of the toroidal current asymmetry and the vertical displacement asymmetry. The Noll relation between asymmetric wall force and vertical current moment is verified in the simulations. Also verified is the toroidal flux asymmetry. Although in many ways, JET is a good predictor of ITER disruption behavior, JET and ITER can be in different parameter regimes, and extrapolating from JET data can overestimate the ITER wall force.
Demonstration of biological piezoelectricity in a spherical protein
Authors: Cockbill Louisa
Published: October 2017

Researchers use a commercial piezometer and custom-built rig to show direct piezoelectricity in protein lysozyme crystals.
Aquaporin AtTIP5;1 as an essential target of gibberellins promotes hypocotyl cell elongation in Arabidopsis thaliana under excess boron stress
Authors: Pang Yongqi , Li Jintong , Qi Bishu , Tian Mi , Sun Lirong , Wang Xuechen , Hao Fushun
Published: October 2017

Aquaporins play essential roles in growth and development including stem elongation in plants. Tonoplast aquaporin AtTIP5;1 has been proposed to positively regulate hypocotyl elongation under high concentrations of boron (high-B) in Arabidopsis thaliana (L.) Heynh. However, the mechanism underlying this process remains unanswered. Here, we show that paclobatrazol, an inhibitor of GA biosynthesis, significantly suppressed the hypocotyl cell elongation of wild-type (WT) seedlings, and more strongly suppressed that of AtTIP5;1 overexpressors under high-B stress. Two AtTIP5;1 null mutants displayed arrested elongation of cells in the upper part of hypocotyls compared with the WT in the presence of high-B or GA3. Moreover, paclobatrazol treatment completely inhibited the increases in AtTIP5;1 transcripts induced by high-B, whereas GA3 application upregulated AtTIP5;1 expression in the WT. In addition, treatment with high-B remarkably elevated the expression levels of GA3ox1, GA20ox1 and GA20ox2 – key biosynthesis genes of GAs – in WT seedlings. The GA3 and GA4 content also increased in WT seedlings grown in MS medium containing high-B. Additionally, application of high-B failed to enhance AtTIP5;1 expression in the double mutant rga-24–gai-t6 of DELLA genes. Together, these results suggest that AtTIP5;1 is an essential downstream target of GAs. High-B induces the accumulation of GAs, which activates AtTIP5;1 through modulation of the DELLA proteins Repressor of ga1–3 and GA-insensitive, further promoting hypocotyl elongation in A. thaliana.
When Two Wrongs Make a Right: Using Conjunctive Enablers to Enhance Evaluations for Extremely Incongruent New Products
Authors: Noseworthy Theodore J , Murray Kyle B , Di Muro Fabrizio
Published: October 2017

The success of new incongruent products hinges largely on whether consumers can efficiently make sense of the product. One of the most efficient ways that people make sense of new objects is through feature-based association. Such associations often incorporate an enabler (e.g., the color green) to help make sense of a semantically related feature (e.g., vitamin enriched). Evidence from three studies suggests that marketers can strategically incorporate enablers in product design to help consumers make sense of an extremely incongruent feature. As a result, consumers tend to reflect more favorably on the product. Furthermore, the authors find that even if the enabler itself is incongruent and leads to lower evaluations on its own, when combined with an atypical feature the effect can still be positive. Thus, a small but semantically meaningful adjustment in design can help marketers successfully introduce extremely incongruent innovations.
Defective synapse maturation and enhanced synaptic plasticity in Shank2-/-mice
Authors: Wegener Stephanie , Buschler Arne , Vanessa Stempel A. , Shoichet Sarah A. , Manahan-Vaughan Denise , Schmitz Dietmar
Published: September 2017

Autism spectrum disorders (ASDs) are neurodevelopmental disorders with a strong genetic aetiology. Since mutations in human SHANK genes have been found in patients with autism, genetic mouse models are employed for a mechanistic understanding of ASDs and the development of therapeutic strategies. In sharp contrast to all studies so far on the function of SHANK proteins, we observe enhanced synaptic plasticity in Shank2-/-mice, under various conditionsin vitroandin vivo. Reproducing and extending previous results, we here present a plausible mechanistic explanation for the mutants' increased capacity for long-term potentiation (LTP) by describing a synaptic maturation deficit in Shank2-/-mice.
Experimental warming reduces the diversity and functional potential of theSphagnummicrobiome
Authors: Carrell Alyssa A. , Kolton Max , Warren Melissa J. , Pelletier Dale A. , Glass Jennifer B. , Kostka Joel E. , Hanson Paul J. , Weston David J.
Published: September 2017

Climate change may reduce biodiversity leading to a reduction in ecosystem productivity. Despite numerous reports of a strong correlation of microbial diversity and ecosystem productivity, little is known about the warming effects on plant associated microbes. Here we explore the impact of experimental warming on the microbial and nitrogen-fixing (diazotroph) community associated with the widespread and ecologically relevantSphagnumgenus in a field warming experiment. To quantify changes in the abundance, diversity, and community composition ofSphagnummicrobiomes with warming we utilized qPCR and Illumina sequencing of the 16S SSU rRNA andnifHgene. Microbial and diazotroph community richness and Shannon diversity decreased with warming (p<0.05). The diazotroph communities shifted from diverse communities to domination by primarilyNostocaceae(25% in control samples to 99% in elevated temperature samples). In addition, the nitrogen fixation activity measured with the acetylene reduction assay (ARA) decreased with warming treatment. This suggests the negative correlation of temperature and microbial diversity corresponds to a reduction in functional potential within the diazotroph community. The results indicate that climate warming may alter the community structure and function in peat moss microbiomes, with implications for impacts to host fitness and ecosystem productivity, and carbon uptake potential of peatlands.
SAMSA2: A standalone metatranscriptome analysis pipeline
Authors: Westreich Samuel T , Treiber Michelle L , Mills David A , Korf Ian , Lemay Danielle G
Published: September 2017

Background

Complex microbial communities are an area of rapid growth in biology. Metatranscriptomics allows one to investigate the gene activity in an environmental sample via high-throughput sequencing. Metatranscriptomic experiments are computationally intensive because the experiments generate a large volume of sequence data and the sequences must be compared with many references.

Results

Here we present SAMSA2, an upgrade to the original Simple Annotation of Metatranscriptomes by Sequence Analysis (SAMSA) pipeline that has been redesigned for use on a supercomputing cluster. SAMSA2 is faster due to the use of the DIAMOND aligner, and more flexible and reproducible because it uses local databases. SAMSA2 is available with detailed documentation, and example input and output files along with examples of master scripts for full pipeline execution.

Conclusions

Using publicly available example data, we demonstrate that SAMSA2 is a rapid and efficient metatranscriptome pipeline for analyzing large paired-end RNA-seq datasets in a supercomputing cluster environment. SAMSA2 provides simplified output that can be examined directly or used for further analyses, and its reference databases may be upgraded, altered or customized to fit the specifics of any experiment.
Complexity of the Relationship between Life Expectancy and Overlap of Lifespans
Authors: Barthold Julia A. , Lenart Adam , Baudisch Annette
Published: September 2017

Longevity has long been recognised as a key facilitator of reciprocal altruism because repeated cooperation of partners hinges on mutual survival. Although demographic tools can be used to quantify mutual survival and expected overlapping lifespans, studies on the evolutionary theory of cooperation take only limited advantage of demography. Overlap of lifespans depends on variation in survival across ages and can be high or low independently of high or low life expectancies. Here we develop formal demographic measures to study the complex relationships between shared life expectancy of two birth cohort peers, the proportion of their lives that they can expect to overlap, and longevity. We simulate age-specific mortality schedules using a Siler model to reveal how infant and senescent mortality, along with age-independent mortality, affect the relationship between the proportion of life shared and life expectancy. We find that while the proportion of life shared can vary vastly for similar life expectancies, almost all changes to mortality schedules that result in higher life expectancies also result in higher proportions of life shared. A distinct exception occurs if life expectancy increases due to lowering the rate of senescence. In this case the proportion of life shared decreases. Our work shows that almost all selective pressures that result in higher life expectancies also result in a larger proportion of life shared. Therefore, selective forces that extend life also improve the chances that a cooperative system would be stable in terms of reciprocal interactions. Since reciprocal interactions may also reduce mortality and result in a feedback loop with the evolution of longevity, our measures and findings can be used for future cross-species comparisons that aim to disentangle predecessor and successor in the evolution of longevity and cooperation.