bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative Chemical Mapping of InGaN Quantum Wells from Calibrated High-Angle Annular Dark Field Micrographs
Authors: Carvalho Daniel , Morales Francisco M. , Ben Teresa , García Rafael , Redondo-Cubero Andrés , Alves Eduardo , Lorenz Katharina , Edwards Paul R. , O’Donnell Kevin P. , Wetzel Christian 
Published: June 2015

AbstractWe present a simple and robust method to acquire quantitative maps of compositional fluctuations in nanostructures from low magnification high-angle annular dark field (HAADF) micrographs calibrated by energy-dispersive X-ray (EDX) spectroscopy in scanning transmission electron microscopy (STEM) mode. We show that a nonuniform background in HAADF-STEM micrographs can be eliminated, to a first approximation, by use of a suitable analytic function. The uncertainty in probe position when collecting an EDX spectrum renders the calibration of HAADF-STEM micrographs indirect, and a statistical approach has been developed to determine the position with confidence. Our analysis procedure, presented in a flowchart to facilitate the successful implementation of the method by users, was applied to discontinuous InGaN/GaN quantum wells in order to obtain quantitative determinations of compositional fluctuations on the nanoscale.
Barriers to Physical Activity in Adolescents
Authors: Langguth Nadine , Könen Tanja , Matulis Simone , Steil Regina , Gawrilow Caterina , Stadler Gertraud 
Published: June 2015

During adolescence, physical activity (PA) decreases with potentially serious, long-term consequences for physical and mental health. Although barriers have been identified as an important PA correlate in adults, research on adolescents’ PA barriers is lacking. Thus reliable, valid scales to measure adolescents’ PA barriers are needed. We present two studies describing a broad range of PA barriers relevant to adolescents with a multidimensional approach. In Study 1, 124 adolescents (age range = 12 – 24 years) reported their most important PA barriers. Two independent coders categorized those barriers. The most frequent PA barriers were incorporated in a multidimensional questionnaire. In Study 2, 598 adolescents (age range = 13 – 21 years) completed this questionnaire and reported their current PA, intention, self-efficacy, and negative outcome expectations. Seven PA barrier dimensions (leisure activities, lack of motivation, screen-based sedentary behavior, depressed mood, physical health, school workload, and preconditions) were confirmed in factor analyses. A multidimensional approach to measuring PA barriers in adolescents is reliable and valid. The current studies provide the basis for developing individually tailored interventions to increase PA in adolescents.
Subjektive Erschöpfung bei stressbezogenen Gesundheitsstörungen
Authors: Waeldin Sandra , Vogt Dominic , Hellhammer Dirk 
Published: June 2015

Erschöpfung kennzeichnet zahlreiche psychische Störungen. Wir haben geprüft, ob die subjektive Erschöpfungsqualität ein verlässlicher Indikator für stressbezogene Gesundheitsstörungen und den daraus resultierenden direkten, indirekten und intangiblen Gesundheitskosten ist. Zur Anwendung kam eine Erschöpfungsskala (Neuropattern-Questionnaire, NPQ-S), deren Cut-off-Werte und Reliabilität anhand einer bevölkerungsrepräsentativen Stichprobe (N = 998) ermittelt wurden. Die Validität wurde bei ambulanten Patienten (N = 455) über Angaben zu psychischen Erkrankungen, gesundheitsbezogenen Kosten und strukturierten Anamnesen sowie einer berufshomogene Stichprobe mit stressbezogenen Beschwerden (N = 69) über Angaben zu Burnout und Gratifikationskrisen untersucht. Die Reliabilität und Validität der Erschöpfungsqualität konnten als gut bis sehr gut eingestuft werden. Die Ergebnisse zeigten, dass ein erhöhtes Ausmaß an Erschöpfung mit erhöhter Stressbelastung, einer erhöhten Chance für verschiedene psychische Erkrankungen sowie erhöhten Kosten (reduziertes Wohlbefinden, häufigere Therapeuten- und Arztbesuche, erhöhter Medikamentenkonsum, mehr Arbeitsunfähigkeitstage) einhergeht. Die Erschöpfungsqualität zeigt sich als störungsübergreifender Indikator und kann als ökonomisches Indikations- und Evaluationsmaß für gesundheitsförderliche Maßnahmen dienen.
Dexamethasone exerts profound immunologic interference on treatment efficacy for recurrent glioblastoma
Authors: Wong E T , Lok E , Gautam S , Swanson K D 
Published: June 2015

Abstract

Background:
Patients with recurrent glioblastoma have a poor outcome. Data from the phase III registration trial comparing tumour-treating alternating electric fields (TTFields) vs chemotherapy provided a unique opportunity to study dexamethasone effects on patient outcome unencumbered by the confounding immune and myeloablative side effects of chemotherapy.

Methods:
Using an unsupervised binary partitioning algorithm, we segregated both cohorts of the trial based on the dexamethasone dose that yielded the greatest statistical difference in overall survival (OS). The results were validated in a separate cohort treated in a single institution with TTFields and their T lymphocytes were correlated with OS.

Results:
Patients who used dexamethasone doses >4.1 mg per day had a significant reduction in OS when compared with those who used ⩽4.1 mg per day, 4.8 vs 11.0 months respectively (χ
2=34.6, P<0.0001) in the TTField-treated cohort and 6.0 vs 8.9 months respectively (χ
2=10.0, P<0.0015) in the chemotherapy-treated cohort. In a single institution validation cohort treated with TTFields, the median OS of patients who used dexamethasone >4.1 mg per day was 3.2 months compared with those who used ⩽4.1 mg per day was 8.7 months (χ
2=11.1, P=0.0009). There was a significant correlation between OS and T-lymphocyte counts.

Conclusions:
Dexamethasone exerted profound effects on both TTFields and chemotherapy efficacy resulting in lower patient OS. Therefore, global immunosuppression by dexamethasone likely interferes with immune functions that are necessary for the treatment of glioblastoma.
Stone-dwelling actinobacteria Blastococcus saxobsidens, Modestobacter marinus and Geodermatophilus obscurus proteogenomes
Authors: Sghaier Haïtham , Hezbri Karima , Ghodhbane-Gtari Faten , Pujic Petar , Sen Arnab , Daffonchio Daniele , Boudabous Abdellatif , Tisa Louis S , Klenk Hans-Peter , Armengaud Jean , Normand Philippe , Gtari Maher 
Published: June 2015

Abstract
The Geodermatophilaceae are unique model systems to study the ability to thrive on or within stones and their proteogenomes (referring to the whole protein arsenal encoded by the genome) could provide important insight into their adaptation mechanisms. Here we report the detailed comparative genome analysis of Blastococcus saxobsidens (Bs), Modestobacter marinus (Mm) and Geodermatophilus obscurus (Go) isolated respectively from the interior and the surface of calcarenite stones and from desert sandy soils. The genome-scale analysis of Bs, Mm and Go illustrates how adaptation to these niches can be achieved through various strategies including ‘molecular tinkering/opportunism’ as shown by the high proportion of lost, duplicated or horizontally transferred genes and ORFans. Using high-throughput discovery proteomics, the three proteomes under unstressed conditions were analyzed, highlighting the most abundant biomarkers and the main protein factors. Proteomic data corroborated previously demonstrated stone-related ecological distribution. For instance, these data showed starvation-inducible, biofilm-related and DNA-protection proteins as signatures of the microbes associated with the interior, surface and outside of stones, respectively.
Viral assemblage composition in Yellowstone acidic hot springs assessed by network analysis
Authors: Bolduc Benjamin , Wirth Jennifer F , Mazurie Aurélien , Young Mark J 
Published: June 2015

Abstract
Understanding of viral assemblage structure in natural environments remains a daunting task. Total viral assemblage sequencing (for example, viral metagenomics) provides a tractable approach. However, even with the availability of next-generation sequencing technology it is usually only possible to obtain a fragmented view of viral assemblages in natural ecosystems. In this study, we applied a network-based approach in combination with viral metagenomics to investigate viral assemblage structure in the high temperature, acidic hot springs of Yellowstone National Park, USA. Our results show that this approach can identify distinct viral groups and provide insights into the viral assemblage structure. We identified 110 viral groups in the hot springs environment, with each viral group likely representing a viral family at the sub-family taxonomic level. Most of these viral groups are previously unknown DNA viruses likely infecting archaeal hosts. Overall, this study demonstrates the utility of combining viral assemblage sequencing approaches with network analysis to gain insights into viral assemblage structure in natural ecosystems.
Optically controlled elastic microcavities
Authors: Flatae Assegid Mengistu , Burresi Matteo , Zeng Hao , Nocentini Sara , Wiegele Sarah , Parmeggiani Camilla , Kalt Heinz , Wiersma Diederik 
Published: June 2015

AbstractWhispering gallery mode (WGM) resonators made from dielectrics like glass or polymers have outstanding optical properties like huge cavity quality (Q) factors which can be achieved on scales compatible with on-chip integration. However, tunability of these resonances is typically difficult to achieve or not suitable for robust device applications. We report here on the fabrication of polymeric micro-goblet WGM resonators with an optically controlled and stable reversible tunability over a large spectral range. This tunability is achieved by integration of photo-responsive liquid crystalline elastomers (LCEs) into micro-goblet cavities. The optical response of the elastomer allows reshaping the goblet by employing low pump power, leading to a fully reversible tuning of the modes. The structure can be realistically implemented in on-chip devices, combining the ultra-high Q factors, typical of WGM resonators, with reliable, optical tunability. This result serves as an example of how light can control light, by invoking a physical reshaping of the structure. This way of optical tuning creates interesting possibilities for all-optical control in circuits, enabling interaction between signal and control beams and the realization of self-tuning cavities.
Vibrational spectroscopy at electrolyte/electrode interfaces with graphene gratings
Authors: Bie Ya-Qing , Horng Jason , Shi Zhiwen , Ju Long , Zhou Qin , Zettl Alex , Yu Dapeng , Wang Feng 
Published: June 2015

AbstractMicroscopic understanding of physical and electrochemical processes at electrolyte/electrode interfaces is critical for applications ranging from batteries, fuel cells to electrocatalysis. However, probing such buried interfacial processes is experimentally challenging. Infrared spectroscopy is sensitive to molecule vibrational signatures, yet to approach the interface three stringent requirements have to be met: interface specificity, sub-monolayer molecular detection sensitivity, and electrochemically stable and infrared transparent electrodes. Here we show that transparent graphene gratings electrode provide an attractive platform for vibrational spectroscopy at the electrolyte/electrode interfaces: infrared diffraction from graphene gratings offers enhanced detection sensitivity and interface specificity. We demonstrate the vibrational spectroscopy of methylene group of adsorbed sub-monolayer cetrimonium bromide molecules and reveal a reversible field-induced electrochemical deposition of cetrimonium bromide on the electrode controlled by the bias voltage. Such vibrational spectroscopy with graphene gratings is promising for real time and in situ monitoring of different chemical species at the electrolyte/electrode interfaces.
A Novel Audiovisual Brain-Computer Interface and Its Application in Awareness Detection
Authors: Wang Fei , He Yanbin , Pan Jiahui , Xie Qiuyou , Yu Ronghao , Zhang Rui , Li Yuanqing 
Published: June 2015

AbstractCurrently, detecting awareness in patients with disorders of consciousness (DOC) is a challenging task, which is commonly addressed through behavioral observation scales such as the JFK Coma Recovery Scale-Revised. Brain-computer interfaces (BCIs) provide an alternative approach to detect awareness in patients with DOC. However, these patients have a much lower capability of using BCIs compared to healthy individuals. This study proposed a novel BCI using temporally, spatially and semantically congruent audiovisual stimuli involving numbers (i.e., visual and spoken numbers). Subjects were instructed to selectively attend to the target stimuli cued by instruction. Ten healthy subjects first participated in the experiment to evaluate the system. The results indicated that the audiovisual BCI system outperformed auditory-only and visual-only systems. Through event-related potential analysis, we observed audiovisual integration effects for target stimuli, which enhanced the discriminability between brain responses for target and nontarget stimuli and thus improved the performance of the audiovisual BCI. This system was then applied to detect the awareness of seven DOC patients, five of whom exhibited command following as well as number recognition. Thus, this audiovisual BCI system may be used as a supportive bedside tool for awareness detection in patients with DOC.
Two-Dimensional Pnictogen Honeycomb Lattice: Structure, On-Site Spin-Orbit Coupling and Spin Polarization
Authors: Lee Jason , Tian Wen-Chuan , Wang Wei-Liang , Yao Dao-Xin 
Published: June 2015

AbstractBecause of its novel physical properties, two-dimensional materials have attracted great attention. From first-principle calculations and vibration frequencies analysis, we predict a new family of two-dimensional materials based on the idea of octet stability: honeycomb lattices of pnictogens (N, P, As, Sb, Bi). The buckled structures of materials come from the sp3 hybridization. These materials have indirect band gap ranging from 0.43 eV to 3.7 eV. From the analysis of projected density of states, we argue that the s and p orbitals together are sufficient to describe the electronic structure under tight-binding model and the tight-binding parameters are obtained by fitting the band structures to first-principle results. Surprisingly large on-site spin-orbit coupling is found for all the pnictogen lattices except nitrogen. Investigation on the electronic structures of both zigzag and armchair nanoribbons reveals the possible existence of spin-polarized ferromagnetic edge states in some cases, which are rare in one-dimensional systems. These edge states and magnetism may exist under the condition of high vacuum and low temperature. This new family of materials would have promising applications in electronics, optics, sensors and solar cells.
Crystallinity of tellurium capping and epitaxy of ferromagnetic topological insulator films on SrTiO3
Authors: Park Jihwey , Soh Yeong-Ah , Aeppli Gabriel , Feng Xiao , Ou Yunbo , He Ke , Xue Qi-Kun 
Published: June 2015

AbstractThin films of topological insulators are often capped with an insulating layer since topological insulators are known to be fragile to degradation. However, capping can hinder the observation of novel transport properties of the surface states. To understand the influence of capping on the surface states, it is crucial to understand the crystal structure and the atomic arrangement at the interfaces. Here, we use x-ray diffraction to establish the crystal structure of magnetic topological insulator Cr-doped (Bi,Sb)2Te3 (CBST) films grown on SrTiO3 (1 1 1) substrates with and without a Te capping layer. We find that both the film and capping layer are single crystal and that the crystal quality of the film is independent of the presence of the capping layer, but that x-rays cause sublimation of the CBST film, which is prevented by the capping layer. Our findings show that the different transport properties of capped films cannot be attributed to a lower crystal quality but to a more subtle effect such as a different electronic structure at the interface with the capping layer. Our results on the crystal structure and atomic arrangements of the topological heterostructure will enable modelling the electronic structure and design of topological heterostructures.
Facile route to freestanding CH3NH3PbI3 crystals using inverse solubility
Authors: Kadro Jeannette M. , Nonomura Kazuteru , Gachet David , Grätzel Michael , Hagfeldt Anders 
Published: June 2015

AbstractCH3NH3PbI3 was found to exhibit inverse solubility at high temperatures in γ-butyrolactone. Making use of this unusual, so far unreported phenomenon, we present a facile method for the growth of freestanding crystals of CH3NH3PbI3 from solution without addition of any capping agents or seed particles. Large, strongly faceted crystals could be grown within minutes. This finding may aid in understanding the crystallization process of CH3NH3PbI3 from solution that may lead to improved morphological control of film deposition for a range of device architectures. Our process offers a facile and rapid route to freestanding crystals for use in a broad range of characterization techniques.
Phenotypic and evolutionary implications of modulating the ERK-MAPK cascade using the dentition as a model
Authors: Marangoni Pauline , Charles Cyril , Tafforeau Paul , Laugel-Haushalter Virginie , Joo Adriane , Bloch-Zupan Agnès , Klein Ophir D. , Viriot Laurent 
Published: June 2015

AbstractThe question of phenotypic convergence across a signalling pathway has important implications for both developmental and evolutionary biology. The ERK-MAPK cascade is known to play a central role in dental development, but the relative roles of its components remain unknown. Here we investigate the diversity of dental phenotypes in Spry2−/−, Spry4−/− and Rsk2−/Y mice, including the incidence of extra teeth, which were lost in the mouse lineage 45 million years ago (Ma). In addition, Sprouty-specific anomalies mimic a phenotype that is absent in extant mice but present in mouse ancestors prior to 9 Ma. Although the mutant lines studied display convergent phenotypes, each gene has a specific role in tooth number determination and crown patterning. The similarities found between teeth in fossils and mutants highlight the pivotal role of the ERK-MAPK cascade during the evolution of the dentition in rodents.
Superdiffusion dominates intracellular particle motion in the supercrowded cytoplasm of pathogenic Acanthamoeba castellanii
Authors: Reverey Julia F. , Jeon Jae-Hyung , Bao Han , Leippe Matthias , Metzler Ralf , Selhuber-Unkel Christine 
Published: June 2015

AbstractAcanthamoebae are free-living protists and human pathogens, whose cellular functions and pathogenicity strongly depend on the transport of intracellular vesicles and granules through the cytosol. Using high-speed live cell imaging in combination with single-particle tracking analysis, we show here that the motion of endogenous intracellular particles in the size range from a few hundred nanometers to several micrometers in Acanthamoeba castellanii is strongly superdiffusive and influenced by cell locomotion, cytoskeletal elements and myosin II. We demonstrate that cell locomotion significantly contributes to intracellular particle motion, but is clearly not the only origin of superdiffusivity. By analyzing the contribution of microtubules, actin and myosin II motors we show that myosin II is a major driving force of intracellular motion in A. castellanii. The cytoplasm of A. castellanii is supercrowded with intracellular vesicles and granules, such that significant intracellular motion can only be achieved by actively driven motion, while purely thermally driven diffusion is negligible.
High performance wash-free magnetic bioassays through microfluidically enhanced particle specificity
Authors: Bechstein Daniel J.B. , Lee Jung-Rok , Ooi Chin Chun , Gani Adi W. , Kim Kyunglok , Wilson Robert J. , Wang Shan X. 
Published: June 2015

AbstractMagnetic biosensors have emerged as a sensitive and versatile platform for high performance medical diagnostics. These magnetic biosensors require well-tailored magnetic particles as detection probes, which need to give rise to a large and specific biological signal while showing very low nonspecific binding. This is especially important in wash-free bioassay protocols, which do not require removal of particles before measurement, often a necessity in point of care diagnostics. Here we show that magnetic interactions between magnetic particles and magnetized sensors dramatically impact particle transport and magnetic adhesion to the sensor surfaces. We investigate the dynamics of magnetic particles’ biomolecular binding and magnetic adhesion to the sensor surface using microfluidic experiments. We elucidate how flow forces can inhibit magnetic adhesion, greatly diminishing or even eliminating nonspecific signals in wash-free magnetic bioassays and enhancing signal to noise ratios by several orders of magnitude. Our method is useful for selecting and optimizing magnetic particles for a wide range of magnetic sensor platforms.
Parity effect of bipolar quantum Hall edge transport around graphene antidots
Authors: Matsuo Sadashige , Nakaharai Shu , Komatsu Katsuyoshi , Tsukagoshi Kazuhito , Moriyama Takahiro , Ono Teruo , Kobayashi Kensuke 
Published: June 2015

AbstractParity effect, which means that even-odd property of an integer physical parameter results in an essential difference, ubiquitously appears and enables us to grasp its physical essence as the microscopic mechanism is less significant in coarse graining. Here we report a new parity effect of quantum Hall edge transport in graphene antidot devices with pn junctions (PNJs). We found and experimentally verified that the bipolar quantum Hall edge transport is drastically affected by the parity of the number of PNJs. This parity effect is universal in bipolar quantum Hall edge transport of not only graphene but also massless Dirac electron systems. These results offer a promising way to design electron interferometers in graphene.
Enzymatic measurement of phosphatidylglycerol and cardiolipin in cultured cells and mitochondria
Authors: Morita Shin-ya , Terada Tomohiro 
Published: June 2015

AbstractPhosphatidylglycerol (PG) and cardiolipin (CL) are synthesized in mitochondria and regulate numerous biological functions. In this study, a novel fluorometric method was developed for measuring PG and CL using combinations of specific enzymes and Amplex Red. This assay quantified the sum of PG and CL (PG + CL) regardless of the species of fatty acyl chain. The calibration curve for PG + CL measurement was linear and the detection limit was 1 μM (10 pmol in the reaction mixture). This new method was applied to the determinations of PG + CL content in HEK293 cells and CL content in purified mitochondria, because the mitochondrial content of PG is negligible compared with that of CL. We demonstrated that the PG+CL content was greater at low cell density than at high cell density. The overexpression of phosphatidylglycerophosphate synthase 1 (PGS1) increased the cellular contents of PG + CL and phosphatidylcholine (PC) and reduced that of phosphatidic acid. PGS1 overexpression also elevated the mitochondrial contents of CL and PC, but had no effect on the number of mitochondria per cell. In addition to the enzymatic measurements of other phospholipids, this simple, sensitive and high-throughput assay for measuring PG + CL can be used to understand cellular, physiological and pathological processes.