bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi-scale thermal stability of niobate-based lead-free piezoceramics with large piezoelectricity
Authors: Zhou Jin-Song , Wang Ke , Yao Fang-Zhou , Zheng Ting , Wu Jiagang , Xiao Dingquan , Zhu Jianguo , Li Jing-Feng
Published: July 2015

Multi-scale thermal stability of (K,Na)NbO3-based perovskites with a high d33 of 430 pC N−1 is investigated, revealing the origin of its large piezoelectricity.
A cryogenic luminescent ratiometric thermometer based on a lanthanide phosphonate dimer
Authors: Ren Min , Brites Carlos D. S. , Bao Song-Song , Ferreira Rute A. S. , Zheng Li-Min , Carlos Luis D.
Published: July 2015

The first example of a ratiometric thermometer based on lanthanide phosphonate is reported, which operates down to the cryogenic temperature range with a maximum relative sensitivity of 3.9% K−1.
Spin-state switches in molecular materials chemistry
Authors: Hayami Shinya , Holmes Stephen M. , Halcrow Malcolm A.
Published: July 2015

Guest editors Shinya Hayami, Stephen M. Holmes and Malcolm A. Halcrow introduce this Journal of Materials Chemistry C themed issue on spin-state switches in molecular materials chemistry.
Milk Flow Rates From Bottle Nipples Used for Feeding Infants Who Are Hospitalized
Authors: Pados Britt F. , Park Jinhee , Thoyre Suzanne M. , Estrem Hayley , Nix W. Brant
Published: July 2015

Purpose

This study tested the milk flow rates and variability in flow of currently available nipples used for bottle-feeding infants who are hospitalized.

Method

Clinicians in 3 countries were surveyed regarding nipples available to them for feeding infants who are hospitalized. Twenty-nine nipple types were identified, and 10 nipples of each type were tested by measuring the amount of infant formula expressed in 1 min using a breast pump. Mean milk flow rate (mL/min) and coefficient of variation were used to compare nipples within brand and within category (i.e., Slow, Standard, Premature).

Results

Flow rates varied widely between nipples, ranging from 2.10 mL/min for the Enfamil Cross-Cut to 85.34 mL/min for the Dr. Brown's Y-Cut Standard Neck. Variability of flow rates among nipples of the same type ranged from a coefficient of variation of 0.05 for Dr. Brown's Level 1 Standard- and Wide-Neck to 0.42 for the Enfamil Cross-Cut. Mean coefficient of variation by brand ranged from 0.08 for Dr. Brown's to 0.36 for Bionix.

Conclusions

Milk flow is an easily manipulated variable that may contribute to the degree of physiologic instability experienced by infants who are medically fragile during oral feeding. This study provides clinicians with information to guide appropriate selection of bottle nipples for feeding infants who are hospitalized.
Iterative beamforming algorithm for improved throughput in multi‐cell multi‐antenna wireless systems
Authors: Bany Salameh Haythem , Hailat Tha'er
Published: July 2015

Mitigating the effects of inter‐cell interference in a multi‐cell wireless network is essential to improve the achieved performance. In this study, the authors develop an iterative distributed beamforming scheme that addresses the effect of inter‐cell interference problem on the downlink of a multi‐cell multi‐antenna wireless system with linear beamformers. The proposed scheme attempts at improving the overall system performance by exploiting network duality principle to jointly compute the optimal transmit and receive beamforming weights such that the desired received power is maximised while minimising the caused interference to other users. Network duality allows the serving base stations and the intended users to jointly compute the beamforming weights of the transmit/receive antenna elements, which improve network performance. The proposed scheme considers variable levels of channel information feedback and different transmit–receive antenna configurations. Simulation results show that a significant performance improvement is achieved through the joint optimisation of the transmit/receive beamforming vectors. Results also indicate that compared with reference schemes, their scheme improves the achieved sum‐rate by up to 50%.
Performance of multitone‐frequency and quadrature‐amplitude modulation over Rayleigh fading channels
Authors: Son Jaeyong , Hong Sungnam , Cheun Kyungwhoon , Yang Kyeongcheol
Published: July 2015

Multitone‐frequency and quadrature‐amplitude modulation (MFQAM) is a combination of multitone frequency‐shift keying and quadrature‐amplitude modulation (QAM). In this study, the authors consider MFQAM with active subcarriers grouped in balance, where the active subcarriers are divided into a specified number of groups and the same QAM symbol is conveyed by every subcarrier in each group. This grouping may make MFQAM have frequency diversity in itself. They first derive the joint probability density function of the correlator outputs of an MFQAM receiver. They then compute the channel capacity of a coded modulation (CM) system employing MFQAM over Rayleigh fading channels. As a result, they demonstrate that for a moderate code rate between 1/3 and 2/3, its normalised throughput is close to the channel capacity limit in the low signal‐to‐noise ratio region, contrary to a CM system employing the conventional modulation. They also evaluate the frame error rate (FER) performance of a CM system employing MFQAM when a non‐binary error‐correcting code is employed. Numerical results demonstrate that the normalised throughput of the CM system computed via the FER shows a similar trend to that obtained via the channel capacity.
Colour retinal fundus image registration by selecting stable extremum points in the scale‐invariant feature transform detector
Authors: Ghassabi Zeinab , Shanbehzadeh Jamshid , Mohammadzadeh Ali , Ostadzadeh Seyed Shervin
Published: July 2015

A fundamental problem of image registration is the determination of corresponding points. The scale‐invariant feature transform (SIFT) is a well‐known algorithm in this regard. However, SIFT suffers from quantity, quality and distribution of the detected points when facing with high‐resolution and low‐contrast colour retinal fundus images. This study introduces an improved SIFT algorithm which identifies adequate, stable and distinctive keypoints with uniform distribution in the overlapped areas. The keypoint of the proposed method is a selection strategy of the difference of Gaussian (DoG) extremum points according to a stability score to guarantee the feature qualities. The stability score is based on the DoG values of extremum points and their vesselness measures in the relevant Gaussian images. Since the selected points lie on the vessels, which are relatively stable between image pairs, the points are unaffected by illumination and content variations of retinal backgrounds. The detected points are introduced to an integrated outlier rejection method. Then, the correspondences determine the geometric transformation parameters. The authors examined quantitatively and qualitatively the performance of this algorithm on four datasets including temporal and partially overlapping image pairs. The experimental results show the outperformance of the approach over similar methods in terms of efficiency, positional accuracy and speed.
Membrane-Stabilizing Agents Improve Quality-of-Life Outcomes for Patients with Lumbar Stenosis
Authors: Bansal Sachin , Lubelski Daniel , Thompson Nicolas R. , Shah Ali A. , Mazanec Daniel J. , Benzel Edward C. , Khalaf Tagreed
Published: July 2015

Study Design

Retrospective cohort controlled study.

Objective

To determine quality-of-life (QOL) outcomes for patients with lumbar spinal stenosis (LSS) treated with membrane-stabilizing agents (MSAs).

Methods

Patients with LSS and concordant neurogenic claudication treated with MSAs ( n = 701) or conservatively without MSAs ( n = 2104) at a single tertiary care hospital were identified. Patient QOL measures (Patient Health Questionnaire-9 [PHQ9], EuroQOL-5 Dimensions [EQ-5D], Pain Disability Questionnaire [PDQ]) were recorded pretreatment and then 4 months following treatment. Propensity score matching was used to account for baseline demographic differences between the two groups. The primary outcome measure was posttreatment improvement in these QOL measures.

Results

Patients in both groups had statistically significant improvements in the EQ-5D. However, the EQ-5D improvement in the MSA group was significantly greater than the improvement in the control group (0.11 versus 0.06; p = 0.0494). The EQ-5D change in the MSA group also exceeded the minimum clinically important difference, thereby suggesting a clinical significance. Both groups had significant pre- to posttreatment improvements in PDQ and PHQ-9, but these changes were not significantly different between the groups.

Conclusion

The results of this study suggest that patients with LSS and neurogenic claudication can have greater QOL improvements when treated with MSAs compared with other forms of conservative management without MSAs.
Periodic orbit analysis of a system with continuous symmetry—A tutorial
Authors: Budanur Nazmi Burak , Borrero-Echeverry Daniel , Cvitanović Predrag
Published: July 2015

Dynamical systems with translational or rotational symmetry arise frequently in studies of spatially extended physical systems, such as Navier-Stokes flows on periodic domains. In these cases, it is natural to express the state of the fluid in terms of a Fourier series truncated to a finite number of modes. Here, we study a 4-dimensional model with chaotic dynamics and SO(2) symmetry similar to those that appear in fluid dynamics problems. A crucial step in the analysis of such a system is symmetry reduction. We use the model to illustrate different symmetry-reduction techniques. The system's relative equilibria are conveniently determined by rewriting the dynamics in terms of a symmetry-invariant polynomial basis. However, for the analysis of its chaotic dynamics, the “method of slices,” which is applicable to very high-dimensional problems, is preferable. We show that a Poincaré section taken on the "slice" can be used to further reduce this flow to what is for all practical purposes a unimodal map. This enables us to systematically determine all relative periodic orbits and their symbolic dynamics up to any desired period. We then present cycle averaging formulas adequate for systems with continuous symmetry and use them to compute dynamical averages using relative periodic orbits. The convergence of such computations is discussed.
Recombination by grain-boundary type in CdTe
Authors: Moseley John , Metzger Wyatt K. , Moutinho Helio R. , Paudel Naba , Guthrey Harvey L. , Yan Yanfa , Ahrenkiel Richard K. , Al-Jassim Mowafak M.
Published: July 2015

We conducted cathodoluminescence (CL) spectrum imaging and electron backscatter diffraction on the same microscopic areas of CdTe thin films to correlate grain-boundary (GB) recombination by GB “type.” We examined misorientation-based GB types, including coincident site lattice (CSL) Σ = 3, other-CSL (Σ = 5–49), and general GBs (Σ > 49), which make up ∼47%–48%, ∼6%–8%, and ∼44%–47%, respectively, of the GB length at the film back surfaces. Statistically averaged CL total intensities were calculated for each GB type from sample sizes of ≥97 GBs per type and were compared to the average grain-interior CL intensity. We find that only ∼16%–18% of Σ = 3 GBs are active non-radiative recombination centers. In contrast, all other-CSL and general GBs are observed to be strong non-radiative centers and, interestingly, these GB types have about the same CL intensity. Both as-deposited and CdCl2-treated films were studied. The CdCl2 treatment reduces non-radiative recombination at both other-CSL and general GBs, but GBs are still recombination centers after the CdCl2 treatment.
A comparison between atrium and courtyard cooling efficiency in hot tropical climate, implementing different passive cooling strategies
Authors: Moosavi Leila , Mahyuddin Norhayati , Ghafar Norafida Ab
Published: July 2015

This paper identifies the most efficient passive cooling strategies implemented in atriums and courtyards in the tropics. For this purpose, a field study of a naturally ventilated atrium building in the tropics is briefly reported upon in which five different modes are defined based on changing the atrium's physical behavior and hybrid evaporative cooling usage. The results are compared with the field study results of two naturally ventilated courtyard houses with the same climate. The results indicate that the highest cooling efficiency is achieved when cross ventilation is coupled with the stack effect in both the atrium and the courtyard (and with evaporative cooling in the atrium), by implementing large inlet openings in the atrium different heights and the courtyard adjacent space (preferably on two opposite sides). In these modes, although the atrium and the courtyard airflow patterns are similar, the atrium also benefits from reverse airflow in the morning. In addition, the airflow pattern has a more important role than the airflow rate in the modification of the indoor thermal condition, in both the atrium and the courtyard.
Study on hairpin-shaped argon plasma jets resonantly excited by microwave pulses at atmospheric pressure
Authors: Chen Zhaoquan , Xia Guangqing , Zou Changlin , Li Ping , Hu Yelin , Ye Qiubo , Eliseev S. , Stepanova O. , Saifutdinov A. I. , Kudryavtsev A. A. , Liu Minghai
Published: July 2015

In the present study, atmospheric pressure argon plasma jets driven by lower-power pulsed microwaves have been proposed with a type of hairpin resonator. The plasma jet plume demonstrates distinctive characteristics, like arched plasma pattern and local plasma bullets. In order to understand how the hairpin resonator works, electromagnetic simulation of the electric field distribution and self-consistent fluid simulation of the interaction between the enhanced electric field and the pulse plasma plume are studied. Simulated spatio-temporal distributions of the electric field, the electron temperature, the electron density, and the absorbed power density have been sampled, respectively. The experimental and simulated results together suggest that the driving mechanism of the hairpin resonator works in the multiple electromagnetic modes of transmission line and microwave resonator, while the local plasma bullets are resonantly generated by local enhanced electric field of surface plasmon polaritons. Moreover, it should be noticed that the radian of the arched plasma plume is mainly affected by the input power and gas flow rate, respectively.
Phenomenological theory of phase transitions in epitaxial BaxSr1−xTiO3 thin films on (111)-oriented cubic substrates
Authors: Shirokov V. B. , Shakhovoy R. A. , Razumnaya A. G. , Yuzyuk Yu. I.
Published: July 2015

A phenomenological thermodynamic theory of BaxSr1−xTiO3 (BST-x) thin films epitaxially grown on (111)-oriented cubic substrates is developed using the Landau-Devonshire approach. The group-theoretical analysis of the low-symmetry phases was performed taking into account two order parameters: the polarization related to ionic shifts in polar zone-center F1u mode and the out-of-phase rotation of TiO6 octahedra corresponding to the R25 zone-boundary mode in the parent cubic phase Pm3¯m. The eight-order thermodynamic potential for BST-x solid solutions was developed and analyzed. We constructed the “concentration-misfit strain” phase diagram for BST-x thin films at room temperature and found that polar rhombohedral R3m phase with the polarization normal to the substrate is stable for x > 0.72 and negative misfit strains, while ferroelectric monoclinic C2 and Cm phases with in-plane polarization are stable for much smaller x and positive or slightly negative misfit strains. We constructed the “temperature-misfit strain” phase diagrams for several concentrations (x = 1, 0.8, 0.6, 0.4, and 0.2). Systematic changes of the phase transition lines between the paraelectric and ferroelectric phases are discussed. The phase diagrams are useful for practical applications in thin-film engineering.
Enhanced electricity generation and pollutant removal in a microbial fuel cell combined with a solar cell
Authors: Sun Zhe , Cao Ruixue , Huang Manhong , Sun Peizhe , Tang Chao , Chen Donghui
Published: July 2015

A new method combined microbial fuel cell (MFC) with polycrystalline silicon solar cell (PSSC) was exploited to investigate its energy generation and its performance on the removal of hexavalent chromium (Cr(VI)). The open circuit voltage (Vocv) of MFC-PSSC could reach 3.540 V, which, to our best knowledge, was the maximum Vocv of MFC reported. The power density of MFC-PSSC was 754.4 mW·m−2 under simulated solar light irradiation, which increased by 990% compared to 76.2 mW·m−2 of a single MFC. The concentration of Cr(VI) in MFC was 17.06 mg·l−1, which was around 12.6 times higher than that in the MFC-PSSC (1.35 mg·l−1) after operation of 48 h. The concentration of chemical oxygen demand in MFC (264 mg·l−1) was around 6 times higher than that in the MFC-PSSC (44 mg·l−1) after operation of 48 h. This study would provide a new insight into the energy generation from MFC coupling with solar cells, and provide exciting opportunities for the utilization of solar energy and bio-energy.
Embodied carbon emissions of foreign trade under the global financial crisis: A case study of Jiangsu province, China
Authors: Wu Changyan , Huang Xianjin , Yang Hong , Lu Qinli , Xu Guoliang , Li Li , Li Jianbao
Published: July 2015

China has been world's largest CO2 emitter since 2008 and the export contributes the majority of its CO2 emissions. Global financial crisis impacted China's export and probably the carbon emission. However, there is no systematic study about the impact of global financial crisis on Chinese carbon emission embodied in international trade (EET), especially from the multi-sector perspective. This research used an input–output analysis model to estimate the total embodied carbon emissions, including direct and indirect carbon emissions in foreign trade from 2005 to 2010 in Jiangsu province, one of the most developed provinces in China. In addition, this research assessed the changes of carbon emissions embodied in foreign trade during the global financial crisis and analyzed the drivers to the changes from multi-sectors using a structural decomposition analysis. Jiangsu was a province with net export emission, and the emissions of both production-based and consumption-based increased during the 2008 financial crisis. Emissions embodied in domestic final demands (CD) increased by 139.4%, while emissions embodied in exports (CE) and emissions embodied in imports (CM) decreased by 29.36% and 81.6%, respectively, from 2008 to 2009. Energy-related sectors (electric and heat power, coal mining and dressing industry, and coking and nuclear fuel processing industry) and manufacturing sector (textile industry) were the main contributors to the change the emissions embodied in international trade. The proportion of export's value of key sectors in all sectors increased annually by 60.7%, while the proportion of import's value grew annually by 55.2% during the global financial crisis. Despite the global financial crisis, the consumption demands were the main factors causing the increase of the total EET from 2008 to 2009. This study highlights the importance of reducing EET by adjusting the trade structure in Jiangsu province and other developed areas in China.
Correlated high-resolution x-ray diffraction, photoluminescence, and atom probe tomography analysis of continuous and discontinuous InxGa1−xN quantum wells
Authors: Ren Xiaochen , Riley James R. , Koleske Daniel D. , Lauhon Lincoln J.
Published: July 2015

Atom probe tomography (APT) is used to characterize the influence of hydrogen dosing during GaN barrier growth on the indium distribution of InxGa1−xN quantum wells, and correlated micro-photoluminescence is used to measure changes in the emission spectrum and efficiency. Relative to the control growth, hydrogen dosing leads to a 50% increase in emission intensity arising from discontinuous quantum wells that are narrower, of lower indium content, and with more abrupt interfaces. Simulations of carrier distributions based on APT composition profiles indicate that the greater carrier confinement leads to an increased radiative recombination rate. Furthermore, APT analysis of quantum well profiles enables refinement of x-ray diffraction analysis for more accurate nondestructive measurements of composition.
A dynamic clustering model of wind farm based on the operation data
Authors: Liu Jizhen , Zhu Mu , Lin Zhongwei , Chen Shihe
Published: July 2015

Due to the increasingly serious environmental problems in China, more and more renewable energy sources, especially wind power, have accessed to the power grid. The unpredictability and the stochastic volatility of wind power has given the power grid a huge challenge. The existing wind farm models may cause the scheduling usually adopt random wind turbine removal, whose effect is often not ideal, and may have the secondary stress on the power grid. In order to solve the problems in the existing models, this paper discusses the dynamic clustering model for the wind farm, where the modeling process is based on the actual wind speed operation data and contains a rolling update process. Through adopting a relatively mature clustering method and the hierarchical clustering method, the precision of the model is obviously improved and the complexity of the model is greatly reduced. The simulation results show the effectiveness of the proposed method.
Tunable metal-insulator transition in Nd1−xYxNiO3 (x = 0.3, 0.4) perovskites thin film at near room temperature
Authors: Shao Tao , Qi Zeming , Wang Yuyin , Li Yuanyuan , Yang Mei , Wang Yu , Zhang Guobin , Liu Miao
Published: July 2015

Metal-insulator transition (MIT) occurs due to the charge disproportionation and lattice distortions in rare-earth nickelates. Existing studies revealed that the MIT behavior of rare-earth nickelates is fairly sensitive to external stress/pressure, suggesting a viable route for MIT strain engineering. Unlike applying extrinsic strain, the MIT can also be modulated by through rare-earth cation mixing, which can be viewed as intrinsic quantum stress. We choose Nd1−XYXNiO3 (x = 0.3, 0.4) perovskites thin films as a prototype system to exhibit the tunable sharp MIT at near room temperature. By adjusting Y concentration, the transition temperature of the thin films can be changed within the range of 340–360 K. X-ray diffraction, X-ray absorption fine structure (XAFS), and in situ infrared spectroscopy are employed to probe the structural and optical property variation affected by composition and temperature. The infrared transmission intensity decreases with temperature across the MIT, indicating a pronounced thermochromic effect. Meanwhile, the XAFS result exhibits that the crystal atomistic structure changes accompanying with the Y atoms incorporation and MIT phase transition. The heavily doped Y atoms result in the pre-edge peak descent and Ni-O bond elongation, suggesting an enhanced charge disproportionation effect and the weakening of hybridization between Ni-3d and O-2p orbits.
Electronic structure of β-Ga2O3 single crystals investigated by hard X-ray photoelectron spectroscopy
Authors: Li Guo-Ling , Zhang Fabi , Cui Yi-Tao , Oji Hiroshi , Son Jin-Young , Guo Qixin
Published: July 2015

By combination of hard X-ray photoelectron spectroscopy (HAXPES) and first-principles band structure calculations, the electronic states of β-Ga2O3 were investigated to deepen the understanding of bulk information for this compound. The valence band spectra of HAXPES presented the main contribution from Ga 4sp, which are well represented by photoionization cross section weighted partial density of states. The experimental data complemented with the theoretical study yield a realistic picture of the electronic structure for β-Ga2O3.
Designing electronic anisotropy of three-dimensional carbon allotropes for the all-carbon device
Authors: Xu Li-Chun , Song Xian-Jiang , Wang Ru-Zhi , Yang Zhi , Li Xiu-Yan , Yan Hui
Published: July 2015

Extending two-dimensional (2D) graphene nanosheets to a three-dimensional (3D) network can enhance the design of all-carbon electronic devices. Based on the great diversity of carbon atomic bonding, we have constructed four superlattice-type carbon allotrope candidates, containing sp2-bonding transport channels and sp3-bonding insulating layers, using density functional theory. It was demonstrated through systematic simulations that the ultra-thin insulating layer with only three-atom thickness can switch off the tunneling transport and isolate the electronic connection between the adjacent graphene strips, and these alternating perpendicular strips also extend the electron road from 2D to 3D. Designing electronic anisotropy originates from the mutually perpendicular π bonds and the rare partial charge density of the corresponding carriers in insulating layers. Our results indicate the possibility of producing custom-designed 3D all-carbon devices with building blocks of graphene and diamond.
Environmental barriers and enablers to physical activity participation among rural adults: a qualitative study
Authors: Cleland Verity , Hughes Clarissa , Thornton Lukar , Squibb Kathryn , Venn Alison , Ball Kylie
Published: July 2015

Issue addressed

Social‐ecological models of health behaviour acknowledge environmental influences, but research examining how the environment shapes physical activity in rural settings is limited. This study aimed to explore the environmental factors that act as barriers or facilitators to physical activity participation among rural adults.

Methods

Forty‐nine adults from three regions of rural Tasmania, Australia, participated in semi‐structured interviews that explored features of the environment that supported or hindered physical activity. Interviews were digitally recorded, transcribed verbatim and analysed thematically.

Results

Four key themes emerged: functionality, diversity, spaces and places for all and realistic expectations. ‘Functionality’ included connectivity with other destinations, distance, safety, continuity, supporting infrastructure and surfacing. While there was limited ‘diversity’ of structured activities and recreational facilities, the importance of easy and convenient access to a natural environment that accommodated physical activity was highlighted. ‘Spaces and places for all’ highlighted the importance of shared‐use areas, particularly those that were family‐ and dog‐friendly. Despite desires for more physical activity opportunities, many participants had ‘realistic expectations’ of what was feasible in rural settings.

Conclusions

Functionality, diversity, spaces and places for all and realistic expectations were identified as considerations important for physical activity among rural adults. Further research using quantitative approaches in larger samples is needed to confirm these findings.
Hostile attributional bias and aggressive behavior in global context
Authors: Dodge Kenneth A. , Malone Patrick S. , Lansford Jennifer E. , Sorbring Emma , Skinner Ann T. , Tapanya Sombat , Tirado Liliana Maria Uribe , Zelli Arnaldo , Alampay Liane Peña , Al-Hassan Suha M. , Bacchini Dario , Bombi Anna Silvia , Bornstein Marc H. , Chang Lei , Deater-Deckard Kirby , Di Giunta Laura , Oburu Paul , Pastorelli Concetta
Published: July 2015

Significance

Interpersonal conflict and violence occur within and between groups around the world. Although not proving causation, this study is significant because it suggests a key psychological mechanism in children’s chronic aggression that might be targeted for intervention: one’s attribution that a peer is acting with hostile intent. When children attribute hostile intent to peers, they are more likely to predict they would react aggressively than when they attribute benign intent. Differences in this tendency statistically account for differences in future chronic aggressive behavior problems across children, as well as differences in chronic aggressive behavior problem rates across ecological-context groups. Identifying this mechanism could lead to novel interventions, education, and policies that reduce or prevent aggressive behavior.
Functional evolution of new and expanded attention networks in humans
Authors: Patel Gaurav H. , Yang Danica , Jamerson Emery C. , Snyder Lawrence H. , Corbetta Maurizio , Ferrera Vincent P.
Published: July 2015

Significance

Macaque monkeys are often used as a model for the biological basis of human cognition. However, the two species last shared a common ancestor 25 million years ago, and in the intervening time the brain areas underlying cognition have likely evolved along different paths. We examined the similarities and differences of human and macaque brain areas underlying attention, a core cognitive ability, by recording brain activity while subjects of both species performed the same attention-demanding task. We found fundamental differences in the attention-related brain areas in the two species, including the complete absence, in monkeys, of a ventral-attention network present in humans. These results shed light on the evolution of the unique properties of the human brain.
Mutation-induced protein interaction kinetics changes affect apoptotic network dynamic properties and facilitate oncogenesis
Authors: Zhao Linjie , Sun Tanlin , Pei Jianfeng , Ouyang Qi
Published: July 2015

Significance

Cancer is highly correlated with somatic mutations. Understanding how mutation induces oncogenesis is an important task in cancer research. We proposed a strategy that combined network-based dynamics modeling with structural-based mutation analysis and molecular dynamics simulation to map cancer-related mutations to network dynamics changes via protein–protein interaction kinetics. This approach identifies the oncogenic role of mutations and subsequently determines the causal mechanism of mutation-induced oncogenesis. This work provides a framework for coupling mutation genotype to tumorigenesis phenotype. It is also a step toward seeking more effective anticancer drug targets in cellular pathways.
A multidrug resistance plasmid contains the molecular switch for type VI secretion in
Acinetobacter baumannii
Authors: Weber Brent S. , Ly Pek Man , Irwin Joshua N. , Pukatzki Stefan , Feldman Mario F.
Published: July 2015

Significance

Although the multidrug-resistant (MDR) bacterium
Acinetobacter baumannii
is a serious threat for health care systems worldwide, very little is known about the mechanisms that have facilitated its rise as a successful pathogen. Our work demonstrates that multiple MDR
A. baumannii
strains regulate the expression of their type VI secretion system (T6SS), an antibacterial apparatus used to kill other bacteria, by harboring a large, self-transmissible resistance plasmid containing T6SS regulatory genes. Through spontaneous plasmid loss,
A. baumannii
activates its T6SS and is able to outcompete other bacteria. However, this comes at a cost, as these strains lose resistance to antibiotics. This mechanism constitutes an apparent survival strategy by
A. baumannii
and provides insights into the pathobiology of this important pathogen.
Evaporative cooling over the Tibetan Plateau induced by vegetation growth
Authors: Shen Miaogen , Piao Shilong , Jeong Su-Jong , Zhou Liming , Zeng Zhenzhong , Ciais Philippe , Chen Deliang , Huang Mengtian , Jin Chun-Sil , Li Laurent Z. X. , Li Yue , Myneni Ranga B. , Yang Kun , Zhang Gengxin , Zhang Yangjian , Yao Tandong
Published: July 2015

Significance

Understanding land-surface biophysical feedbacks to the atmosphere is needed if we are to simulate regional climate accurately. In the Arctic, previous studies have shown that enhanced vegetation growth decreases albedo and amplifies warming. In contrast, on the Tibetan Plateau, a statistical model based on in situ observations and decomposition of the surface energy budget suggests that increased vegetation activity may attenuate daytime warming by enhancing evapotranspiration (ET), a cooling process. A regional climate model also simulates daytime cooling when prescribed with increased vegetation activity, but with a magnitude smaller than observed, likely because this model simulates weaker ET enhancement in response to increased vegetation growth.
Matrix cross-linking–mediated mechanotransduction promotes posttraumatic osteoarthritis
Authors: Kim Jin-Hong , Lee Gyuseok , Won Yoonkyung , Lee Minju , Kwak Ji-Sun , Chun Churl-Hong , Chun Jang-Soo
Published: July 2015

Significance

Osteoarthritic cartilage destruction is caused primarily by an imbalance between chondrocyte catabolism and anabolism. Various proinflammatory cytokines that disrupt this metabolic balance during osteoarthritis (OA) pathogenesis have been identified. Here, in addition to these biochemical pathways, we demonstrate that changes in the biophysical properties of the chondrocyte microenvironment triggered by cartilage matrix cross-linking play a causal role in OA pathogenesis. Two major OA risk factors, aging and mechanical stress, cause matrix stiffening via nonenzymatic and enzymatic collagen cross-linking through the accumulation of advanced glycation end-products and the upregulation of lysyl oxidase, respectively. Data from the current study illustrate the dynamic nature of physical remodeling of cartilage ECM and elucidate the key mechanotransduction pathway regulating chondrocyte metabolism and osteoarthritic cartilage destruction.
High-resolution in vivo imaging of mouse brain through the intact skull
Authors: Park Jung-Hoon , Sun Wei , Cui Meng
Published: July 2015

Significance

Multiphoton microscopy has been the gold standard for in vivo deep-tissue imaging. The long laser wavelength suffers less scattering, and the 3D-confined excitation permits the use of scattered signal light, which greatly improves the imaging depth. However, the direct application of this method to highly turbid media has been limited. Here, we present a microscope system demonstrating high resolution in vivo imaging inside highly turbid tissue. We use advanced wavefront correction with an adaptive correction plane-positioning system to compensate high-order aberrations over an extended corrected field of view. Using this technique, we demonstrate submicron-resolution imaging of neural dendrites and microglia dynamics through the intact skulls of adult mice.
Prefrontal neurons encode context-based response execution and inhibition in reward seeking and extinction
Authors: Moorman David E. , Aston-Jones Gary
Published: July 2015

Significance

The prefrontal cortex (PFC) regulates multiple aspects of behavior. One hypothesis proposes that PFC segregates different functions into specific subregions: dorsal medial PFC [mPFC; prelimbic (PL)] regulates execution of behavior, or “going,” whereas ventral mPFC [infralimbic (IL)] regulates inhibition of behavior, or “stopping.” We demonstrate that neither PL nor IL neurons exhibited signals specifically tied to going or stopping, either during reward seeking or extinction sessions when rats stopped seeking reward. Instead, neurons better represented the outcome based context, firing more strongly for going during reward seeking and for stopping during extinction. The use of contextual information to guide responding is important for maximizing benefits vs. costs and may be a major role of the PFC in optimizing behavior.
Tangential migration of neuronal precursors of glutamatergic neurons in the adult mammalian brain
Authors: Sun Gerald J. , Zhou Yi , Stadel Ryan P. , Moss Jonathan , Yong Jing Hui A. , Ito Shiori , Kawasaki Nicholas K. , Phan Alexander T. , Oh Justin H. , Modak Nikhil , Reed Randall R. , Toni Nicolas , Song Hongjun , Ming Guo-li
Published: July 2015

Significance

Mammalian brain development is a complex, ordered process whereby newborn neurons follow stereotyped migration modes to organize into specific patterns required for complicated neural circuit formation. Classically, principal excitatory neurons are thought to organize into radial columns that underlie the basic brain circuits, whereas inhibitory neurons disperse tangentially across these columns to modulate the principal circuits. These principles are thought to be fundamental to the genesis of the complex mammalian brain. Surprisingly, we found that precursors for excitatory principal neurons exhibit tangential migration in the adult mammalian brain. Our findings enrich our understanding of neurodevelopment and lay important conceptual groundwork for studies of brain plasticity, disease, and repair.
Absence of Jahn−Teller transition in the hexagonal Ba
3
CuSb
2
O
9
single crystal
Authors: Katayama Naoyuki , Kimura Kenta , Han Yibo , Nasu Joji , Drichko Natalia , Nakanishi Yoshiki , Halim Mario , Ishiguro Yuki , Satake Ryuta , Nishibori Eiji , Yoshizawa Masahito , Nakano Takehito , Nozue Yasuo , Wakabayashi Yusuke , Ishihara Sumio , Hagiwara Masayuki , Sawa Hiroshi , Nakatsuji Satoru
Published: July 2015

Significance

The quantum spin liquid state has been intensively pursued since Anderson proposed the resonating valence bond model. On the other hand, quantum liquids based on another electronic degree of freedom, orbital, has been believed unrealistic, because the energy scale of orbital correlation is normally one order of magnitude higher than spin exchange coupling, resulting in an orbital ordering at a signicantly high temperature accompanied by a cooperative Jahn−Teller (JT) distortion. In this paper, we present striking complete suppression of the JT transition in the copper oxide, 6
H
-Ba
3
CuSb
2
O
9
based on comprehensive structural studies, indicating the realization of the novel “spin–orbital liquid” state.
High-throughput analysis of yeast replicative aging using a microfluidic system
Authors: Jo Myeong Chan , Liu Wei , Gu Liang , Dang Weiwei , Qin Lidong
Published: July 2015

Significance

Advancing our understanding of the underlying molecular mechanisms of aging, as well as their contributions to age-associated diseases, will have a profound impact on public health. Studying the replicative aging phenomenon in the budding yeast
Saccharomyces cerevisiae
has led to significant findings on how aging is regulated by evolutionarily conserved enzymes and molecular pathways. We have developed a microfluidic system that enables the visualization and analysis of the complete replicative lifespan of a single yeast cell. This system overcomes current technical challenges in low-throughput yeast lifespan analysis by providing a fast, high-throughput, and accurate analytical method at the single-cell level. This approach opens a new avenue for aging and longevity research using yeast genetic screens.
Distinct speed dependence of entorhinal island and ocean cells, including respective grid cells
Authors: Sun Chen , Kitamura Takashi , Yamamoto Jun , Martin Jared , Pignatelli Michele , Kitch Lacey J. , Schnitzer Mark J. , Tonegawa Susumu
Published: July 2015

Significance

The importance of entorhinal–hippocampal circuits in the mammalian brain for an animal’s spatial and episodic experience is known, but the neural basis for these different spatial computations is unclear. Medial entorhinal cortex layer II contains island and ocean cells that project via separate pathways into hippocampus. We performed Ca
2+
imaging in freely exploring mice using cellular markers and a miniature head-mounted fluorescence microscope, the first time (to our knowledge) in entorhinal cortex. We found that, although both oceans and islands contain grid cells, islands are significantly more speed modulated than oceans. We speculate that this differential property reflects islands’ and oceans’ contribution to different downstream functions.
Functional expression of sodium-glucose transporters in cancer
Authors: Scafoglio Claudio , Hirayama Bruce A. , Kepe Vladimir , Liu Jie , Ghezzi Chiara , Satyamurthy Nagichettiar , Moatamed Neda A. , Huang Jiaoti , Koepsell Hermann , Barrio Jorge R. , Wright Ernest M.
Published: July 2015

Significance

Cancers require high amounts of glucose to grow and survive, and dogma is that uptake is facilitated by passive glucose transporters (GLUTs). We have identified a new mechanism to import glucose into pancreatic and prostate cancer cells, namely active glucose transport mediated by sodium-dependent glucose transporters (SGLTs). This means that the specific radioactive imaging probe for SGLTs, α-methyl-4-deoxy-4-[
18
F]fluoro-
d
-glucopyranoside, may be used along with positron-emission tomography to diagnose and stage pancreatic and prostate cancers, tumors in which the GLUT probe 2-[
18
F]fluoro-2-deoxy-
d
-glucose has questionable utility. Moreover, we suggest, based on our results in mouse models, that Food and Drug Administration-approved SGLT2 inhibitors may be used to reduce the viability of pancreatic and prostate cancer cells in patients.
Opposing roles of STAT1 and STAT3 in IL-21 function in CD4
+
T cells
Authors: Wan Chi-Keung , Andraski Allison B. , Spolski Rosanne , Li Peng , Kazemian Majid , Oh Jangsuk , Samsel Leigh , Swanson Phillip A. , McGavern Dorian B. , Sampaio Elizabeth P. , Freeman Alexandra F. , Milner Joshua D. , Holland Steven M. , Leonard Warren J.
Published: July 2015

Significance

IL-21 is a type I cytokine important for immune cell differentiation and function. We found that transcription factors STAT1 and STAT3 play partially opposing roles in IL-21 function in CD4
+
T cells. Both STAT1 and STAT3 control IL-21–mediated gene regulation, with some genes, including
Ifng
,
Tbx21
, and
Il21
reciprocally regulated by these STATs. IFN-γ production was also differentially regulated by these STATs in vitro during CD4
+
T-cell differentiation and in vivo during chronic lymphocytic choriomeningitis infection. Importantly, IL-21–induced
IFNG
and
TBX21
expression was higher in CD4
+
T cells from patients with autosomal dominant hyper-IgE syndrome or with STAT1 gain-of-function mutations, suggesting that dys-regulated IL-21–STAT signaling partially explains the clinical manifestations of these patients.
How osmolytes influence hydrophobic polymer conformations: A unified view from experiment and theory
Authors: Mondal Jagannath , Halverson Duncan , Li Isaac T. S. , Stirnemann Guillaume , Walker Gilbert C. , Berne Bruce J.
Published: July 2015

Significance

Osmolytes influence protein structure by either promoting (protecting osmolytes) or disrupting (denaturing osmolytes) the folding process. Current consensus is that protecting osmolytes [trimethylamine N-oxide (TMAO)] act by being excluded from the protein surface while denaturing osmolytes (urea) bind to it. However there is little knowledge about the molecular mechanism of osmolyte action on hydrophobic macromolecules, which form the core of most proteins. This work, through a combination of single-molecule atomic force microscopy experiments and computer simulations, investigates the collapse behavior of a hydrophobic polymer polystyrene in TMAO and urea. The mechanism of osmolyte action on hydrophobic macromolecules is distinct from that of a protein, but, despite key differences, both mechanisms comply with the standard thermodynamic theory of preferential osmolyte binding.
Counselor Training and Attitudes toward Pharmacotherapies for Opioid use Disorder
Authors: Aletraris Lydia , Edmond Mary Bond , Paino Maria , Fields Dail , Roman Paul M.
Published: July 2015

Background

Methadone and buprenorphine have been demonstrated to be effective in the treatment of opioid use disorder (OUD), especially when combined with psychosocial treatment. Despite buprenorphine's association with fewer withdrawal symptoms and lessened risk of abuse, compared with methadone, its adoption remains limited. Given the vital role that counselors may play in its successful implementation, their knowledge and perceptions of opioid agonist therapy may be facilitators or barriers to its acceptance.

Methods

Informed by diffusion theory, the current study examined perceptions of buprenorphine's and methadone's acceptability among 725 counselors employed in a nationally representative sample of substance use disorder treatment centers. First, we provided descriptive statistics about medication diffusion, extent of training received about the medications, and perceptions of acceptability of each medication. Then, we compared acceptability of opioid agonists with other treatment approaches for OUD. Finally, we conducted 2 ordinary least squares regressions to examine counselor acceptability of buprenorphine and of methadone.

Results

Descriptive statistics suggested that diffusion of information about buprenorphine and methadone was not complete, and training was not extensive for either medication. Counselors reported greater acceptability and training of buprenorphine compared with methadone. Methadone was rated as the least acceptable among all other treatment approaches. Multivariate analyses indicated regional differences, and that medication-specific training, adaptability, and educational attainment were positively related with perceptions of acceptability of either medication, even after controlling for organizational characteristics. Adherence to a 12-step orientation was negatively associated with acceptability.

Conclusions

Dissemination of information about opioid agonist therapy is occurring. Nevertheless, the fact that 20% of counselors admitted not knowing enough about either buprenorphine's or methadone's effectiveness is surprising in light of the extensive literature documenting their effectiveness. Future research should focus upon different types of training that can inform physicians, counselors, and patients about the use of opioid agonist therapy.
CIN85 modulates TGFβ signaling by promoting the presentation of TGFβ receptors on the cell surface
Authors: Yakymovych Ihor , Yakymovych Mariya , Zang Guangxiang , Mu Yabing , Bergh Anders , Landström Maréne , Heldin Carl-Henrik
Published: July 2015

Members of the transforming growth factor β (TGFβ) family initiate cellular responses by binding to TGFβ receptor type II (TβRII) and type I (TβRI) serine/threonine kinases, whereby Smad2 and Smad3 are phosphorylated and activated, promoting their association with Smad4. We report here that TβRI interacts with the SH3 domains of the adaptor protein CIN85 in response to TGFβ stimulation in a TRAF6-dependent manner. Small interfering RNA–mediated knockdown of CIN85 resulted in accumulation of TβRI in intracellular compartments and diminished TGFβ-stimulated Smad2 phosphorylation. Overexpression of CIN85 instead increased the amount of TβRI at the cell surface. This effect was inhibited by a dominant-negative mutant of Rab11, suggesting that CIN85 promoted recycling of TGFβ receptors. CIN85 enhanced TGFβ-stimulated Smad2 phosphorylation, transcriptional responses, and cell migration. CIN85 expression correlated with the degree of malignancy of prostate cancers. Collectively, our results reveal that CIN85 promotes recycling of TGFβ receptors and thereby positively regulates TGFβ signaling.
Tracking individual secretory vesicles during exocytosis reveals an ordered and regulated process
Authors: Donovan Kirk W. , Bretscher Anthony
Published: July 2015

Post-Golgi secretory vesicle trafficking is a coordinated process, with transport and regulatory mechanisms to ensure appropriate exocytosis. While the contributions of many individual regulatory proteins to this process are well studied, the timing and dependencies of events have not been defined. Here we track individual secretory vesicles and associated proteins in vivo during tethering and fusion in budding yeast. Secretory vesicles tether to the plasma membrane very reproducibly for ∼18 s, which is extended in cells defective for membrane fusion and significantly lengthened and more variable when GTP hydrolysis of the exocytic Rab is delayed. Further, the myosin-V Myo2p regulates the tethering time in a mechanism unrelated to its interaction with exocyst component Sec15p. Two-color imaging of tethered vesicles with Myo2p, the GEF Sec2p, and several exocyst components allowed us to document a timeline for yeast exocytosis in which Myo2p leaves 4 s before fusion, whereas Sec2p and all the components of the exocyst disperse coincident with fusion.