bluuebunny/crossref_metadata_2025 huggingface dataset:
Fibrocyte-like cells mediate acquired resistance to anti-angiogenic therapy with bevacizumab
Authors: Mitsuhashi Atsushi , Goto Hisatsugu , Saijo Atsuro , Trung Van The , Aono Yoshinori , Ogino Hirokazu , Kuramoto Takuya , Tabata Sho , Uehara Hisanori , Izumi Keisuke , Yoshida Mitsuteru , Kobayashi Hiroaki , Takahashi Hidefusa , Gotoh Masashi , Kakiuchi Soji , Hanibuchi Masaki , Yano Seiji , Yokomise Hiroyasu , Sakiyama Shoji , Nishioka Yasuhiko
Published: December 2015

Bevacizumab exerts anti-angiogenic effects in cancer patients by inhibiting vascular endothelial growth factor (VEGF). However, its use is still limited due to the development of resistance to the treatment. Such resistance can be regulated by various factors, although the underlying mechanisms remain incompletely understood. Here we show that bone marrow-derived fibrocyte-like cells, defined as alpha-1 type I collagen-positive and CXCR4-positive cells, contribute to the acquired resistance to bevacizumab. In mouse models of malignant pleural mesothelioma and lung cancer, fibrocyte-like cells mediate the resistance to bevacizumab as the main producer of fibroblast growth factor 2. In clinical specimens of lung cancer, the number of fibrocyte-like cells is significantly increased in bevacizumab-treated tumours, and correlates with the number of treatment cycles, as well as CD31-positive vessels. Our results identify fibrocyte-like cells as a promising cell biomarker and a potential therapeutic target to overcome resistance to anti-VEGF therapy.
Dual functions of Rap1 are crucial for T-cell homeostasis and prevention of spontaneous colitis
Authors: Ishihara Sayaka , Nishikimi Akihiko , Umemoto Eiji , Miyasaka Masayuki , Saegusa Makoto , Katagiri Koko
Published: December 2015

Rap1-GTP activates leukocyte function-associated antigen-1 (LFA-1) to induce arrest on the high endothelial venule (HEV). Here we show that Rap1-GDP restrains rolling behaviours of T cells on the peripheral lymph node addressin (PNAd), P-selectin and mucosal addressin cell adhesion molecule-1 (MadCAM-1) by inhibiting tether formation. Consequently, Rap1 deficiency impairs homing of naive T cells to peripheral lymph nodes, but accelerates homing of TH17 and TH1 cells to the colon, resulting in spontaneous colitis with tumours. Rap1-GDP associates with and activates lymphocyte-oriented kinase, which phosphorylates ERM (ezrin, radixin and moesin) in resting T cells. Phosphomimetic ezrin reduces the rolling of Rap1-deficient cells, and thereby decreases their homing into the colon. On the other hand, chemokines activate Rap1 at the plasma membrane within seconds, and Rap1-GTP binds to filamins, which diminishes its association with the β2 chain of LFA-1 and results in LFA-1 activation. This Rap1-dependent regulation of T-cell circulation prevents the onset of colitis.
Real-space collapse of a polariton condensate
Authors: Dominici L. , Petrov M. , Matuszewski M. , Ballarini D. , De Giorgi M. , Colas D. , Cancellieri E. , Silva Fernández B. , Bramati A. , Gigli G. , Kavokin A. , Laussy F. , Sanvitto D.
Published: December 2015

Microcavity polaritons are two-dimensional bosonic fluids with strong nonlinearities, composed of coupled photonic and electronic excitations. In their condensed form, they display quantum hydrodynamic features similar to atomic Bose–Einstein condensates, such as long-range coherence, superfluidity and quantized vorticity. Here we report the unique phenomenology that is observed when a pulse of light impacts the polariton vacuum: the fluid which is suddenly created does not splash but instead coheres into a very bright spot. The real-space collapse into a sharp peak is at odd with the repulsive interactions of polaritons and their positive mass, suggesting that an unconventional mechanism is at play. Our modelling devises a possible explanation in the self-trapping due to a local heating of the crystal lattice, that can be described as a collective polaron formed by a polariton condensate. These observations hint at the polariton fluid dynamics in conditions of extreme intensities and ultrafast times.
Tunable-Porosity Membranes From Discrete Nanoparticles
Authors: Marchetti Patrizia , Mechelhoff Martin , Livingston Andrew G.
Published: December 2015

Thin film composite membranes were prepared through a facile single-step wire-wound rod coating procedure in which internally crosslinked poly(styrene-co-butadiene) polymer nanoparticles self-assembled to form a thin film on a hydrophilic ultrafiltration support. This nanoparticle film provided a defect-free separation layer 130–150 nm thick, which was highly permeable and able to withstand aggressive pH conditions beyond the range of available commercial membranes. The nanoparticles were found to coalesce to form a rubbery film when heated above their glass transition temperature (Tg). The retention properties of the novel membrane were strongly affected by charge repulsion, due to the negative charge of the hydroxyl functionalized nanoparticles. Porosity was tuned by annealing the membranes at different temperatures, below and above the nanoparticle Tg. This enabled fabrication of membranes with varying performance. Nanofiltration properties were achieved with a molecular weight cut-off below 500 g mol−1 and a low fouling tendency. Interestingly, after annealing above Tg, memory of the interstitial spaces between the nanoparticles persisted. This memory led to significant water permeance, in marked contrast to the almost impermeable films cast from a solution of the same polymer.
Efficiency and safety of surgical intervention to patients with Non-Cystic Fibrosis bronchiectasis: a meta-analysis
Authors: Fan Li-Chao , Liang Shuo , Lu Hai-Wen , Fei Ke , Xu Jin-Fu
Published: December 2015

No quantitative systematic review was found to report the efficiency and safety of surgical resection in the management of non-cystic fibrosis (non-CF) bronchiectasis. We therefore conducted a meta-analysis to assess the effects of operative intervention to patients with non-CF bronchiectasis. PubMed, the Cochrane library and Web of Science databases were searched up to July 8th, 2015. The pooled mortality from 34 studies recruiting 4788 patients was 1.5% (95% CI, 0.9–2.5%). The pooled morbidity from 33 studies consisting of 4583 patients was 16.7% (95% CI, 14.8–18.6%). The pooled proportion of patients from 35 studies, consisting of 4614 patients who were free of symptoms was 66.5% (95% CI, 61.3–71.7%) after surgery. The summary proportion of patients from 35 articles including 4279 participants who were improved was 27.5% (95% CI, 22.5–32.5%) and 9.1% (95% CI, 7.3–11.5%) showed no clinical improvement. In conclusion, our analysis indicated that lung resection in the management of non-CF bronchiectasis is associated with significant improvements in symptoms, low risk of mortality and acceptable morbidity.
Reciprocal immune benefit based on complementary production of antibiotics by the leech Hirudo verbana and its gut symbiont Aeromonas veronii
Authors: Tasiemski Aurélie , Massol François , Cuvillier-Hot Virginie , Boidin-Wichlacz Céline , Roger Emmanuel , Rodet Franck , Fournier Isabelle , Thomas Frédéric , Salzet Michel
Published: December 2015

The medicinal leech has established a long-term mutualistic association with Aeromonas veronii, a versatile bacterium which can also display free-living waterborne and fish- or human-pathogenic lifestyles. Here, we investigated the role of antibiotics in the dynamics of interaction between the leech and its gut symbiont Aeromonas. By combining biochemical and molecular approaches, we isolated and identified for the first time the antimicrobial peptides (AMPs) produced by the leech digestive tract and by its symbiont Aeromonas. Immunohistochemistry data and PCR analyses evidenced that leech AMP genes are induced in the gut epithelial cells when Aeromonas load is low (starved animals), while repressed when Aeromonas abundance is the highest (post blood feeding). The asynchronous production of AMPs by both partners suggests that these antibiotic substances (i) provide them with reciprocal protection against invasive bacteria and (ii) contribute to the unusual simplicity of the gut microflora of the leech. This immune benefit substantially reinforces the evidence of an evolutionarily stable association between H. verbana and A. veronii. Altogether these data may provide insights into the processes making the association with an Aeromonas species in the digestive tract either deleterious or beneficial.
Productivity and sustainability of rainfed wheat-soybean system in the North China Plain: results from a long-term experiment and crop modelling
Authors: Qin Wei , Wang Daozhong , Guo Xisheng , Yang Taiming , Oenema Oene
Published: December 2015

A quantitative understanding of yield response to water and nutrients is key to improving the productivity and sustainability of rainfed cropping systems. Here, we quantified the effects of rainfall, fertilization (NPK) and soil organic amendments (with straw and manure) on yields of a rainfed wheat-soybean system in the North China Plain (NCP), using 30-years’ field experimental data (1982–2012) and the simulation model-AquaCrop. On average, wheat and soybean yields were 5 and 2.5 times higher in the fertilized treatments than in the unfertilized control (CK), respectively. Yields of fertilized treatments increased and yields of CK decreased over time. NPK + manure increased yields more than NPK alone or NPK + straw. The additional effect of manure is likely due to increased availability of K and micronutrients. Wheat yields were limited by rainfall and can be increased through soil mulching (15%) or irrigation (35%). In conclusion, combined applications of fertilizer NPK and manure were more effective in sustaining high crop yields than recommended fertilizer NPK applications. Manure applications led to strong accumulation of NPK and relatively low NPK use efficiencies. Water deficiency in wheat increased over time due to the steady increase in yields, suggesting that the need for soil mulching increases.
Glycosylation of Dentin Matrix Protein 1 is critical for osteogenesis
Authors: Sun Yao , Weng Yuteng , Zhang Chenyang , Liu Yi , Kang Chen , Liu Zhongshuang , Jing Bo , Zhang Qi , Wang Zuolin
Published: December 2015

Proteoglycans play important roles in regulating osteogenesis. Dentin matrix protein 1 (DMP1) is a highly expressed bone extracellular matrix protein that regulates both bone development and phosphate metabolism. After glycosylation, an N-terminal fragment of DMP1 protein was identified as a new proteoglycan (DMP1-PG) in bone matrix. In vitro investigations showed that Ser89 is the key glycosylation site in mouse DMP1. However, the specific role of DMP1 glycosylation is still not understood. In this study, a mutant DMP1 mouse model was developed in which the glycosylation site S89 was substituted with G89 (S89G-DMP1). The glycosylation level of DMP1 was down-regulated in the bone matrix of S89G-DMP1 mice. Compared with wild type mice, the long bones of S89G-DMP1 mice showed developmental changes, including the speed of bone remodeling and mineralization, the morphology and activities of osteocytes and activities of both osteoblasts and osteoclasts. These findings indicate that glycosylation of DMP1 is a key posttranslational modification process during development and that DMP1-PG functions as an indispensable proteoglycan in osteogenesis.
Experimental observation of weak non-Markovianity
Authors: Bernardes Nadja K. , Cuevas Alvaro , Orieux Adeline , Monken C. H. , Mataloni Paolo , Sciarrino Fabio , Santos Marcelo F.
Published: December 2015

Non-Markovianity has recently attracted large interest due to significant advances in its characterization and its exploitation for quantum information processing. However, up to now, only non-Markovian regimes featuring environment to system backflow of information (strong non-Markovianity) have been experimentally simulated. In this work, using an all-optical setup we simulate and observe the so-called weak non-Markovian dynamics. Through full process tomography, we experimentally demonstrate that the dynamics of a qubit can be non-Markovian despite an always increasing correlation between the system and its environment which, in our case, denotes no information backflow. We also show the transition from the weak to the strong regime by changing a single parameter in the environmental state, leading us to a better understanding of the fundamental features of non-Markovianity.
Secretome identification of immune cell factors mediating metastatic cell homing
Authors: Aguado Brian A. , Wu Jia J. , Azarin Samira M. , Nanavati Dhaval , Rao Shreyas S. , Bushnell Grace G. , Medicherla Chaitanya B. , Shea Lonnie D.
Published: December 2015

Metastatic cell homing is a complex process mediated in part by diffusible factors secreted from immune cells found at a pre-metastatic niche. We report on connecting secretomics and TRanscriptional Activity CEll aRray (TRACER) data to identify functional paracrine interactions between immune cells and metastatic cells as novel mediators of homing. Metastatic breast cancer mouse models were used to generate a diseased splenocyte conditioned media (D-SCM) containing immune cell secreted factors. MDA-MB-231 metastatic cell activity including cell invasion, migration, transendothelial migration and proliferation were increased in D-SCM relative to control media. Our D-SCM secretome analysis yielded 144 secreted factor candidates that contribute to increased metastatic cell activity. The functional mediators of homing were identified using MetaCore software to determine interactions between the immune cell secretome and the TRACER-identified active transcription factors within metastatic cells. Among the 5 candidate homing factors identified, haptoglobin was selected and validatedin vitroandin vivoas a key mediator of homing. Our studies demonstrate a novel systems biology approach to identify functional signaling factors associated with a cellular phenotype, which provides an enabling tool that complements large-scale protein identification provided by proteomics.
Sub-10 nm near-field localization by plasmonic metal nanoaperture arrays with ultrashort light pulses
Authors: Lee Hongki , Kim Chulhong , Kim Donghyun
Published: December 2015

Near-field localization by ultrashort femtosecond light pulses has been investigated using simple geometrical nanoapertures. The apertures employ circular, rhombic and triangular shapes to localize the distribution of surface plasmon. To understand the geometrical effect on the localization, aperture length and period of the nanoapertures were varied. Aperture length was shown to affect the performance more than aperture period due mainly to intra-aperture coupling of near-fields. Triangular apertures provided the strongest spatial localization below 10 nm in size as well as the highest enhancement of field intensity by more than 7000 times compared to the incident light pulse. Use of ultrashort pulses was found to allow much stronger light localization than with continuous-wave light. The results can be used for super-localization sensing and imaging applications where spatially localized fields can break through the limits in achieving improved sensitivity and resolution.
Unexpected Fascicle Length Changes In Denervated Feline Soleus Muscle During Stance Phase Of Walking
Authors: Mehta Ricky , Maas Huub , Gregor Robert J. , Prilutsky Boris I.
Published: December 2015

After surgical repair of traumatically severed peripheral nerves, associated muscles are paralyzed for weeks. Little is known about fascicle length changes in paralyzed muscles during locomotion. The aim of this study was to investigate to what extent, if any, muscle fascicles of denervated feline soleus (SO) change length during stance of walking when intact SO synergists are actively contracting. Hindlimb kinematics, SO fascicle and muscle-tendon unit (MTU) length and EMG activity of SO, lateral gastrocnemius (LG) and medial gastrocnemius (MG) were measured during level and slope walking in adult cats. Measurements were taken before and 1–2 weeks following SO-LG denervation. Unexpectedly, SO fascicle lengthening and shortening during stance in all walking conditions were evident after denervation. The greatest SO fascicle shortening (17.3 ± 2.2% of a reference length) and least fascicle lengthening (1.5 ± 0.8%) after denervation were found during upslope walking, where MG EMG activity was greatest across slopes (P < 0.05) and greatest discrepancies between post denervation SO fascicle and MTU length changes occurred. These findings suggest that myofascial linkages between denervated SO and its active synergists might affect its fascicle length changes. Further studies are needed to directly test this suggestion.
ICE1 of Pyrus ussuriensis functions in cold tolerance by enhancing PuDREBa transcriptional levels through interacting with PuHHP1
Authors: Huang Xiaosan , Li Kongqing , Jin Cong , Zhang Shaoling
Published: December 2015

ICE1 transcription factor plays an important role in plant cold stress via regulating the expression of stress-responsive genes. In this study, a PuICE1 gene isolated from Pyrus ussuriensis was characterized for its function in cold tolerance. The expression levels of the PuICE1 were induced by cold, dehydration and salt, with the greatest induction under cold conditions. PuICE1 was localized in the nucleus and could bind specifically to the MYC element in the PuDREBa promoter. The PuICE1 fused to the GAL4 DNA-binding domain to have transcriptional activation activity. Ectopic expression of the PuICE1 in tomato conferred enhanced tolerance to cold stress at cold temperatures, less electrolyte leakage, less MDA content, higher chlorophyll content, higher survival rate, higher proline content, higher activities of enzymes. In additon, steady-state mRNA levels of six stress-responsive genes coding for either functional or regulatory genes were induced to higher levels in the transgenic lines by cold stress. Yeast two-hybrid, transient assay, split luciferase complementation and BiFC assays all revealed that PuHHP1 protein can physically interact with PuICE1. Taken together, these results demonstrated that PuICE1 plays a positive role in cold tolerance, which may be due to enhancement of PuDREBa transcriptional levels through interacting with the PuHHP1.
Tracing the Flow of Perceptual Features in an Algorithmic Brain Network
Authors: Ince Robin A. A. , van Rijsbergen Nicola J. , Thut Gregor , Rousselet Guillaume A. , Gross Joachim , Panzeri Stefano , Schyns Philippe G.
Published: December 2015

The model of the brain as an information processing machine is a profound hypothesis in which neuroscience, psychology and theory of computation are now deeply rooted. Modern neuroscience aims to model the brain as a network of densely interconnected functional nodes. However, to model the dynamic information processing mechanisms of perception and cognition, it is imperative to understand brain networks at an algorithmic level–i.e. as the information flow that network nodes code and communicate. Here, using innovative methods (Directed Feature Information), we reconstructed examples of possible algorithmic brain networks that code and communicate the specific features underlying two distinct perceptions of the same ambiguous picture. In each observer, we identified a network architecture comprising one occipito-temporal hub where the features underlying both perceptual decisions dynamically converge. Our focus on detailed information flow represents an important step towards a new brain algorithmics to model the mechanisms of perception and cognition.
Human embryonic stem cell-derived mesenchymal cells preserve kidney function and extend lifespan in NZB/W F1 mouse model of lupus nephritis
Authors: Thiel Austin , Yavanian Gregory , Nastke Maria-Dorothea , Morales Peter , Kouris Nicholas A. , Kimbrel Erin A. , Lanza Robert
Published: December 2015

Adult tissue-derived mesenchymal stromal cells (MSCs) are showing promise in clinical trials for systemic lupus erythematosus (SLE). However, the inability to manufacture large quantities of functional cells from a single donor as well as donor-dependent variability in quality limits their clinical utility. Human embryonic stem cell (hESC)-derived MSCs are an alternative to adult MSCs that can circumvent issues regarding scalability and consistent quality due to their derivation from a renewable starting material. Here, we show that hESC-MSCs prevent the progression of fatal lupus nephritis (LN) in NZB/W F1 (BWF1) mice. Treatment led to statistically significant reductions in proteinuria and serum creatinine and preserved renal architecture. Specifically, hESC-MSC treatment prevented disease-associated interstitial inflammation, protein cast deposition and infiltration of CD3+ lymphocytes in the kidneys. This therapy also led to significant reductions in serum levels of tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6), two inflammatory cytokines associated with SLE. Mechanistically, in vitro data support these findings, as co-culture of hESC-MSCs with lipopolysaccharide (LPS)-stimulated BWF1 lymphocytes decreased lymphocyte secretion of TNFα and IL-6 and enhanced the percentage of putative regulatory T cells. This study represents an important step in the development of a commercially scalable and efficacious cell therapy for SLE/LN.
Population genetic study of 34 X-Chromosome markers in 5 main ethnic groups of China
Authors: Zhang Suhua , Bian Yingnan , Li Li , Sun Kuan , wang Zheng , Zhao Qi , Zha Lagabaiyila , Cai Jifeng , Gao Yuzhen , Ji Chaoneng , Li Chengtao
Published: December 2015

As a multi-ethnic country, China has some indigenous population groups which vary in culture and social customs, perhaps as a result of geographic isolation and different traditions. However, upon close interactions and intermarriage, admixture of different gene pools among these ethnic groups may occur. In order to gain more insight on the genetic background of X-Chromosome from these ethnic groups, a set of X-markers (18 X-STRs and 16 X-Indels) was genotyped in 5 main ethnic groups of China (HAN, HUI, Uygur, Mongolian, Tibetan). Twenty-three private alleles were detected in HAN, Uygur, Tibetan and Mongolian. Significant differences (p < 0.0001) were all observed for the 3 parameters of heterozygosity (Ho, He and UHe) among the 5 ethnic groups. Highest values of Nei genetic distance were always observed at HUI-Uygur pairwise when analyzed with X-STRs or X-Indels separately and combined. Phylogenetic tree and PCA analyses revealed a clear pattern of population differentiation of HUI and Uygur. However, the HAN, Tibetan and Mongolian ethnic groups were closely clustered. Eighteen X-Indels exhibited in general congruent phylogenetic signal and similar cluster among the 5 ethnic groups compared with 16 X-STRs. Aforementioned results proved the genetic polymorphism and potential of the 34 X-markers in the 5 ethnic groups.
Single Particle Dynamic Imaging and Fe3+ Sensing with Bright Carbon Dots Derived from Bovine Serum Albumin Proteins
Authors: Yang Qingxiu , Wei Lin , Zheng Xuanfang , Xiao Lehui
Published: December 2015

In this work, we demonstrated a convenient and green strategy for the synthesis of highly luminescent and water-soluble carbon dots (Cdots) by carbonizing carbon precursors, i.e., Bovine serum albumin (BSA) nanoparticles, in water solution. Without post surface modification, the as-synthesized Cdots exhibit fluorescence quantum yield (Q.Y.) as high as 34.8% and display superior colloidal stability not only in concentrated salt solutions (e.g. 2 M KCl) but also in a wide range of pH solutions. According to the FT-IR measurements, the Cdots contain many carboxyl groups, providing a versatile route for further chemical and biological functionalization. Through conjugation of Cdots with the transacting activator of transcription (TAT) peptide (a kind of cell penetration peptide (CPP)) derived from human immunodeficiency virus (HIV), it is possible to directly monitor the dynamic interactions of CPP with living cell membrane at single particle level. Furthermore, these Cdots also exhibit a dosage-dependent selectivity toward Fe3+ among other metal ions, including K+, Na+, Mg2+, Hg2+, Co2+, Cu2+, Pb2+ and Al3+. We believed that the Cdots prepared by this strategy would display promising applications in various areas, including analytical chemistry, nanomedicine, biochemistry and so on.
Observation of uniaxial anisotropy along the [100] direction in crystalline Fe film
Authors: Bac Seul-Ki , Lee Hakjoon , Lee Sangyoep , Choi Seonghoon , Yoo Taehee , Lee Sanghoon , Liu X. , Furdyna J. K.
Published: December 2015

We report an observation of uniaxial magnetic anisotropy along the [100] crystallographic direction in crystalline Fe film grown on Ge buffers deposited on a (001) GaAs substrate. As expected, planar Hall resistance (PHR) measurements reveal the presence of four in-plane magnetic easy axes, indicating the dominance of the "Equation missing" cubic anisotropy in the film. However, systematic mapping of the PHR hysteresis loops observed during magnetization reversal at different field orientations shows that the easy axes along the "Equation missing" and "Equation missing" are not equivalent. Such breaking of the cubic symmetry can only be ascribed to the presence of uniaxial anisotropy along the "Equation missing" direction of the Fe film. Analysis of the PHR data measured as a function of orientation of the applied magnetic field allowed us to quantify the magnitude of this "Equation missing" uniaxial anisotropy field as "Equation missing" Oe. Although this value is only 1.5% of cubic anisotropy field, its presence significantly changes the process of magnetization reversal, revealing the important role of the "Equation missing" uniaxial anisotropy in Fe films. Breaking of the cubic symmetry in the Fe film deposited on a Ge buffer is surprising and we discuss possible reason for this unexpected behavior.
Contribution of human and climate change impacts to changes in streamflow of Canada
Authors: Tan Xuezhi , Gan Thian Yew
Published: December 2015

Climate change exerts great influence on streamflow by changing precipitation, temperature, snowpack and potential evapotranspiration (PET), while human activities in a watershed can directly alter the runoff production and indirectly through affecting climatic variables. However, to separate contribution of anthropogenic and natural drivers to observed changes in streamflow is non-trivial. Here we estimated the direct influence of human activities and climate change effect to changes of the mean annual streamflow (MAS) of 96 Canadian watersheds based on the elasticity of streamflow in relation to precipitation, PET and human impacts such as land use and cover change. Elasticities of streamflow for each watershed are analytically derived using the Budyko Framework. We found that climate change generally caused an increase in MAS, while human impacts generally a decrease in MAS and such impact tends to become more severe with time, even though there are exceptions. Higher proportions of human contribution, compared to that of climate change contribution, resulted in generally decreased streamflow of Canada observed in recent decades. Furthermore, if without contributions from retreating glaciers to streamflow, human impact would have resulted in a more severe decrease in Canadian streamflow.
Reduced GeO2 Nanoparticles: Electronic Structure of a Nominal GeOx Complex and Its Stability under H2 Annealing
Authors: Zhao Jia , Yang Linju , McLeod John A. , Liu Lijia
Published: December 2015

A nominal GeOx (x ≤ 2) compound contains mixtures of Ge, Ge suboxides and GeO2, but the detailed composition and crystallinity could vary from material to material. In this study, we synthesize GeOx nanoparticles by chemical reduction of GeO2 and comparatively investigate the freshly prepared sample and the sample exposed to ambient conditions. Although both compounds are nominally GeOx, they exhibit different X-ray diffraction patterns. X-ray absorption fine structure (XAFS) is utilized to analyse the detailed structure of GeOx. We find that the two initial GeOx compounds have entirely different compositions: the fresh GeOx contains large amorphous Ge clusters connected by GeOx, while after air exposure; the Ge clusters are replaced by a GeO2-GeOx composite. In addition, the two GeOx products undergo different structural rearrangement under H2 annealing, producing different intermediate phases before ultimately turning into metallic Ge. In the fresh GeOx, the amorphous Ge remains stable, with the GeOx being gradually reduced to Ge, leading to a final structure of crystalline Ge grains connected by GeOx. The air-exposed GeOx on the other hand, undergoes a GeO2→GeOx→Ge transition, in which H2 induces the creation of oxygen vacancies at intermediate stage. A complete removal of oxides occurs at high temperature.
Arsenic stress after the Proterozoic glaciations
Authors: Chi Fru Ernest , Arvestål Emma , Callac Nolwenn , El Albani Abderrazak , Kilias Stephanos , Argyraki Ariadne , Jakobsson Martin
Published: December 2015

Protection against arsenic damage in organisms positioned deep in the tree of life points to early evolutionary sensitization. Here, marine sedimentary records reveal a Proterozoic arsenic concentration patterned to glacial-interglacial ages. The low glacial and high interglacial sedimentary arsenic concentrations, suggest deteriorating habitable marine conditions may have coincided with atmospheric oxygen decline after ~2.1 billion years ago. A similar intensification of near continental margin sedimentary arsenic levels after the Cryogenian glaciations is also associated with amplified continental weathering. However, interpreted atmospheric oxygen increase at this time, suggests that the marine biosphere had widely adapted to the reorganization of global marine elemental cycles by glaciations. Such a glacially induced biogeochemical bridge would have produced physiologically robust communities that enabled increased oxygenation of the ocean-atmosphere system and the radiation of the complex Ediacaran-Cambrian life.
Understanding the Unique Electronic Properties of Nano Structures Using Photoemission Theory
Authors: Kwon Soonnam , Choi Won Kook
Published: December 2015

Newly emerging experimental techniques such as nano-ARPES are expected to provide an opportunity to measure the electronic properties of nano-materials directly. However, the interpretation of the spectra is not simple because it must consider quantum mechanical effects related to the measurement process itself. Here, we demonstrate a novel approach that can overcome this problem by using an adequate simulation to corroborate the experimental results. Ab initio calculation on arbitrarily-shaped or chemically ornamented nano-structures is elaborately correlated to photoemission theory. This correlation can be directly exploited to interpret the experimental results. To test this method, a direct comparison was made between the calculation results and experimental results on highly-oriented pyrolytic graphite (HOPG). As a general extension, the unique electronic structures of nano-sized graphene oxide and features from the experimental result of black phosphorous (BP) are disclosed for the first time as supportive evidence of the usefulness of this method. This work pioneers an approach to intuitive and practical understanding of the electronic properties of nano-materials.
Dispersive liquid–liquid microextraction coupled with single-drop microextraction for the fast determination of sulfonamides in environmental water samples by high performance liquid chromatography-ultraviolet detection
Authors: Li Xiaoyi , Li Quanle , Xue Aifang , Chen Hao , Li Shengqing
Published: December 2015

A simple coupling of low-density solvent-based solvent-demulsification dispersive liquid–liquid microextraction (2-min pre-extraction) and single-drop microextraction (15-min back-extraction).
Metal-free oxidative cross-coupling of diazirines with arylboronic acids
Authors: Wu Guojiao , Zhao Xia , Ji Wenzhi , Zhang Yan , Wang Jianbo
Published: December 2015

The metal-free cross-coupling of diazirines with arylboronic acids under oxidative conditions affords a series of substituted olefins in good yields.
Graphene oxide-templated preferential growth of continuous MOF thin films
Authors: Kim Daeok , Coskun Ali
Published: December 2015

A graphene oxide film was used as an interfacial template for the preferential growth of continuous HKUST-1 films on a solid substrate.
Molecular structure and dynamics of an aqueous sodium chloride solution in nano-pores between portlandite surfaces: a molecular dynamics study
Authors: Dongshuai Hou , Zeyu Lu , Peng Zhang , Qingjun Ding
Published: December 2015

Structures of water molecules and ions in the vicinity of the surface of portlandite.
Additive polarizabilities in ionic liquids
Authors: Bernardes Carlos E. S. , Shimizu Karina , Lopes José Nuno Canongia , Marquetand Philipp , Heid Esther , Steinhauser Othmar , Schröder Christian
Published: December 2015

An extended designed regression analysis of experimental data on density and refractive indices of several classes of ionic liquids yielded statistically averaged atomic volumes and polarizabilities of the constituting atoms.
The curious case of zeolite–clay/binder interactions and their consequences for catalyst preparation
Authors: Whiting Gareth T. , Chowdhury Abhishek Dutta , Oord Ramon , Paalanen Pasi , Weckhuysen Bert M.
Published: December 2015

Zeolite-based catalyst bodies are commonly employed in a range of important industrial processes. Depending on the binder and shaping method chosen, vast differences in the reactivity, selectivity and stability are obtained. Here, three highly complementary micro-spectroscopic techniques were employed to study zeolite ZSM-5–binder interactions in SiO2-, Al2O3-, SiO2 : Al2O3- (2 : 1 mix) and kaolinite-bound catalyst pellets. We establish how their preparation influences the zeolite–clay/binder interactions. Using thiophene as an acid-catalyzed staining reaction, light absorbing oligomers produced in each sample were followed. To our surprise, kaolinite decreased the overall reactivity of the sample due to the phase change of the binder, creating a hard impenetrable outer layer. Aluminum migration to the zeolite was observed when Al2O3was selected as a binder, creating additional Brønsted acid sites, which favored the formation of ring-opened thiophene oligomers compared to the larger oligomer species produced when SiO2was used as a binder. In the latter case, the interaction of the Si–OH groups in the binder with thiophene was revealed to have a large impact in creating such large oligomer species. Furthermore, the combination of a SiO2 : Al2O3mix as a binder enhanced the reactivity, possibly due to the creation of additional Brønsted acid sites between the two binder components during pellet preparation. It is evident that, independent of the shaping method, the intimate contact between the zeolite and binder heavily impacts the reactivity and product selectivity, with the type of binder playing a vital role.
Micro-dissected tumor tissues on chip: an ex vivo method for drug testing and personalized therapy
Authors: Astolfi M. , Péant B. , Lateef M. A. , Rousset N. , Kendall-Dupont J. , Carmona E. , Monet F. , Saad F. , Provencher D. , Mes-Masson A.-M. , Gervais T.
Published: December 2015

Micro-dissected tumor tissues (MDTs) are maintained alive on chip for several days and show promising results for personalized medicine applications.
Molecular insight into arsenic toxicity via the genome-wide deletion mutant screening of Saccharomyces cerevisiae
Authors: Johnson Adam J. , Veljanoski Filip , O’Doherty Patrick J. , Zaman Mohammad S. , Petersingham Gayani , Bailey Trevor D. , Münch Gerald , Kersaitis Cindy , Wu Ming J.
Published: December 2015

Arsenic is omnipresent in soil, air, food and water.
Spirochromone-chalcone conjugates as antitubercular agents: synthesis, bio evaluation and molecular modeling studies
Authors: Mujahid M. , Yogeeswari P. , Sriram D. , Basavanag U. M. V. , Díaz-Cervantes Erik , Córdoba-Bahena Luis , Robles Juvencio , Gonnade R. G. , Karthikeyan M. , Vyas Renu , Muthukrishnan M.
Published: December 2015

We report new spiro chromone scaffold derived molecules possessingin vitroanti-tubercular activities. QSAR based molecular modeling studies correlated the bioactivities with the frontier molecular orbital energies.
Probing the enzyme kinetics, allosteric modulation and activation of α1- and α2-subunit-containing AMP-activated protein kinase (AMPK) heterotrimeric complexes by pharmacological and physiological activators
Authors: Rajamohan Francis , Reyes Allan R. , Frisbie Richard K. , Hoth Lise R. , Sahasrabudhe Parag , Magyar Rachelle , Landro James A. , Withka Jane M. , Caspers Nicole L. , Calabrese Matthew F. , Ward Jessica , Kurumbail Ravi G.
Published: December 2015

AMP-activated protein kinase (AMPK) is a serine/threonine protein kinase that serves as a pleotropic regulator of whole body energy homoeostasis. AMPK exists as a heterotrimeric complex, composed of a catalytic subunit (α) and two regulatory subunits (β and γ), each present as multiple isoforms. In the present study, we compared the enzyme kinetics and allosteric modulation of six recombinant AMPK isoforms, α1β1γ1, α1β2γ1, α1β2γ3, α2β1γ1, α2β2γ1 and α2β2γ3 using known activators, A769662 and AMP. The α1-containing complexes exhibited higher specific activities and lower Km values for a widely used peptide substrate (SAMS) compared with α2-complexes. Surface plasmon resonance (SPR)-based direct binding measurements revealed biphasic binding modes with two distinct equilibrium binding constants for AMP, ADP and ATP across all isoforms tested. The α2-complexes were ∼25-fold more sensitive than α1-complexes to dephosphorylation of a critical threonine on their activation loop (pThr172/174). However, α2-complexes were more readily activated by AMP than α1-complexes. Compared with β1-containing heterotrimers, β2-containing AMPK isoforms are less sensitive to activation by A769662, a synthetic activator. These data demonstrate that ligand induced activation of AMPK isoforms may vary significantly based on their AMPK subunit composition. Our studies provide insights for the design of isoform-selective AMPK activators for the treatment of metabolic diseases.
Dynamic Assessment With Bilinguals: A Focus on Increasing Clinicians' Confidence
Authors: Gorman Brenda K.
Published: December 2015

Speech-language pathologists (SLPs) are obligated to judiciously select and administer appropriate assessments without inherent cultural or linguistic bias (Individuals with Disabilities Education Act [IDEA], 2004). Nevertheless, clinicians continue to struggle with appropriate assessment practices for bilingual children, and diagnostic decisions are too often based on standardized tests that were normed predominately on monolingual English speakers (Caesar & Kohler, 2007). Dynamic assessment is intended to be a valid and unbiased approach for ascertaining what a child knows and can do, yet many speech-language pathologists (SLPs) struggle in knowing what and how to assess within this paradigm. Therefore, the aim of this paper is to present a clinical scenario and summarize extant research on effective dynamic language assessment practices, with a focus on specific language tasks and procedures, in order to foster SLPs' confidence in their use of dynamic assessment with bilingual children.
Effect of Bilingualism on Multitasking: A Pilot Study
Authors: Hsieh Li
Published: December 2015

Bilingual speakers rely on attentional and executive control to continuously inhibit or activate linguistic representations of competing languages, which leads to an increased efficiency known as “bilingual advantage”. Both monolingual and bilingual speakers were asked to perform multiple tasks of talking on a cell phone while simultaneously attending to simulated driving events. This study examined the effect of bilingualism on participants' performance during a dual-task experiment based on 20 monolingual and 13 bilingual healthy adults. The within-subject and between-subject comparisons were conducted on reaction times of a visual event detection task for (a) only driving and (b) driving while simultaneously engaged in a phone conversation. Results of this study showed that bilingual speakers performed significantly faster than monolingual speakers during the multitasking condition, but not during the driving only condition. Further, bilingual speakers consistently showed a bilingual advantage in reaction times during the multitasking condition, despite varying degrees on a bilingual dominance scale. Overall, experiences in more than one language yield bilingual advantage in better performance than monolingual speakers during a multitasking condition, but not during a single task condition. Regardless of the difference in bilingual proficiency level, such language experience reveals a positive impact on bilingual speakers for multitasking.
Concept for narrow‐band filtering rat‐race coupler using dual‐mode cross‐shaped dielectric
Authors: Jiao Lingxiao , Wu Yongle , Liu Yuanan , Wang Weimin , Chen Jian‐Xin
Published: December 2015

A new concept for a narrow‐band filtering rat‐race coupler is reported, which is constructed by a dual‐mode cross‐shaped dielectric resonator (DR). By arranging the two modes of the dual‐mode DR, the functions for a rat‐race coupler are realised, and the bandpass filtering characteristic is integrated. Meanwhile, the single‐cavity configuration results in a miniaturised size. An experiment on a fabricated prototype has validated this novel concept.
Integrated‐optic lattice‐form tuneable chromatic dispersion compensator with increased number of operable channels
Authors: Takiguchi K.
Published: December 2015

A lattice‐form tuneable chromatic dispersion compensator whose number of operable channels is doubled by adding an interleave filter is reported. In this scheme, interleaved signals are introduced into two different inputs of the lattice‐form compensator, and are provided with the same dispersion compensation value every half free spectral range. Thus, this configuration can activate inoperable channels that account for nearly half of the total bandwidth in existing lattice‐form compensators. The proposed compensator was fabricated by monolithically integrating all components with silica‐waveguide technology. The dispersion compensation value of −321 to 299 ps/nm was obtained over 40 GHz bandwidth with a channel period of 50 GHz.
Murmur‐adaptive compression technique for phonocardiogram signals
Authors: Kim Sunjung , Hwang Dosik
Published: December 2015

As mobile and wearable health technologies have evolved, constant monitoring of bio‐signals from patients has become important for accurate diagnosis using mobile and remote health services. As the need for constant monitoring of bio‐signals increases, the amount of bio‐signal data also increases, therefore an efficient compression method for specific bio‐signals should be developed. In contrast to other types of signals, bio‐signals contain important diagnostic information that should not be removed during compression. An effective compression algorithm for phonocardiogram (PCG) signals that contain important diagnostic information (murmur) is proposed. In this algorithm, the murmur is first estimated, then an adaptive thresholding scheme is applied in the wavelet domain to the normal portions and the murmur portions of PCGs depending on the murmur estimates during compression. Although other conventional compression methods result in substantial loss of murmur information, the proposed method is able to keep most of the murmur information in compressed PCGs.
Characteristics of nearest level modulation method with circulating current control for modular multilevel converter
Authors: Wu Deliang , Peng Li
Published: December 2015

The nearest level modulation combined with circulating current control (denoted by NLM‐C method) is applied for modular multilevel converter. The characteristic of the NLM‐C method in terms of output voltage level and total harmonic distortion (THD) is studied and is compared with conventional NLM and the modified level‐increasing NLM method without circulating current control (M‐NLM method). The impact of circulating current control on the waveform of the ac output voltage with NLM‐C method is studied. Compared with the conventional NLM method, besides suppressing the second order harmonic in the circulating current, the NLM‐C method can also increase the output voltage level number and reduce the output voltage and/or current THD, which is similar to the M‐NLM method. The impact of sampling frequency on the accuracy of circulating current control with NLM‐C is analysed. A step‐by‐step method is presented in order to select the sampling frequency for achieving optimal circulating current control performance when using the NLM‐C method. The analysis in this study is verified by simulation results.
Anisotropy of the magnetic properties of the FeTe0.65Se0.35 superconductor
Authors: Bondarenko S. I. , Bludov O. M. , Wisniewski A. , Gawryluk D. , Dudar I. S. , Koverya V. P. , Monarkha V. Yu. , Sivakov A. G. , Timofeev V. P.
Published: December 2015

The magnetization anisotropy of a layered superconductor FeTe0.65Se0.35 sample is experimentally studied in a magnetic field directed either along the layers of the plane, or perpendicular to them. The value of the vortex pinning potential in a weak magnetic field, and the critical current density ratio are determined for these directions. The results are discussed within the framework of presenting the sample as layers of fine single crystals, divided by weak interlayer superconducting bonds with magnetic inclusions.
Femtosecond laser structuring of silver-containing glass: Silver redistribution, selective etching, and surface topology engineering
Authors: Desmoulin Jean-Charles , Petit Yannick , Canioni Lionel , Dussauze Marc , Lahaye Michel , Gonzalez Hernando Magallanes , Brasselet Etienne , Cardinal Thierry
Published: December 2015

Femtosecond direct laser writing in silver-containing phosphate glasses allows for the three-dimensional (3D) implementation of complex photonic structures. Sample translation along or perpendicular to the direction of the beam propagation has been performed, which led to the permanent formation of fluorescent structures, either corresponding to a tubular shape or to two parallel planes at the vicinity of the interaction voxel, respectively. These optical features are related to significant modifications of the local material chemistry. Indeed, silver depletion areas with a diameter below 200 nm were evidenced at the center of the photo-produced structures while photo-produced luminescence properties are attributed to the formation of silver clusters around the multiphoton interaction voxel. The laser-triggered oxidation-reduction processes and the associated photo-induced silver redistribution are proposed to be at the origin of the observed original 3D luminescent structures. Thanks to such material structuring, surface engineering has been also demonstrated. Selective surface chemical etching of the glass has been obtained subsequently to laser writing at the location of the photo-produced structures, revealing features with nanometric depth profiles and radial dimensions strongly related to the spatial distributions of the silver clusters.