bluuebunny/crossref_metadata_2025 huggingface dataset:
A facile approach to prepare biomimetic composite separators toward safety-enhanced lithium secondary batteries
Authors: Lee Taejoo , Lee Yunju , Ryou Myung-Hyun , Lee Yong Min
Published: April 2015

A mussel-inspired polydopamine (PDA) coating makes radio-frequency Al2O3 sputtering a damage-free, reliable, and cost-efficient process for polyethylene (PE) surface modification for lithium secondary batteries (LIBs).
Improved electrochemical performance of onion-like carbon coated magnetite nanocapsules as electromagnetic absorptive anode materials for lithium-ion batteries
Authors: Bi Nannan , Liu Xianguo , Wu Niandu , Cui Caiyun , Sun Yuping
Published: April 2015

The synthesis of magnetite (Fe3O4)@C nanocapsules with Fe3O4nanoparticles as the core and onion-like carbon as the shell has been reported.
Reduced graphene oxide-polyaniline composites—synthesis, characterization and optimization for thermoelectric applications
Authors: Mitra Mousumi , Kulsi Chiranjit , Chatterjee Krishanu , Kargupta Kajari , Ganguly Saibal , Banerjee Dipali , Goswami Shyamaprosad
Published: April 2015

Reduced graphene oxide (rGO) can improve the thermoelectric properties of polyaniline (PANI) by varying its concentration in composites of rGO nanosheets and PANI.
New D–π–A organic dyes containing a tert-butyl-capped indolo[3,2,1-jk]carbazole donor with bithiophene unit as π-linker for dye-sensitized solar cells
Authors: Cao Wei , Fang Manman , Chai Zhaofei , Xu Han , Duan Tainan , Li Zhen , Chen Xingguo , Qin Jingui , Han Hongwei
Published: April 2015

A new kind of D–π–A organic dye containing a tert-butyl-capped indolo[3,2,1-jk]carbazole unit as a donor with bithiophene unit as a π bridge and cyanoacrylic acid as an acceptor has been designed and synthesized for DSSCs.
Ultra-low Ru-promoted CuCl2 as highly active catalyst for the hydrochlorination of acetylene
Authors: Xu Jiangtao , Zhao Jia , Zhang Tongtong , Di Xiaoxia , Gu Shanchuan , Ni Jun , Li Xiaonian
Published: April 2015

We reported a synergy between Ru and Cu, obtaining a highly active catalyst for acetylene hydrochlorination, which improved the TOF of Cu to ca. 1.81 min−1 and showed that the Cu–Ru catalyst is an alternative to the toxic conventional HgCl2 catalyst.
Rapid microwave assisted hydrothermal synthesis of porous α-Fe2O3nanostructures as stable and high capacity negative electrode for lithium and sodium ion batteries
Authors: Nageswara Rao B. , Ramesh Kumar P. , Padmaraj O. , Venkateswarlu M. , Satyanarayana N.
Published: April 2015

Porous α-Fe2O3nanostructures were developed in the presence of a base catalyst by a rapid microwave assisted hydrothermal method.
Core–shell Co3O4/α-Fe2O3 heterostructure nanofibers with enhanced gas sensing properties
Authors: Cao Jing , Wang Ziying , Wang Rui , Liu Sen , Fei Teng , Wang Lijie , Zhang Tong
Published: April 2015

1D Co3O4/α-Fe2O3 core–shell nanofibers were successfully fabricated by a facile and template-free coaxial electrospinning method, and developed for acetone gas detection.
Highly-twisted, continuous nanofibre yarns prepared by a hybrid needle-needleless electrospinning technique
Authors: Shuakat Muhammad Nadeem , Lin Tong
Published: April 2015

A hybrid needle-needleless electrospinning technique has been developed to directly convert polymer solution into a highly-twisted, continuous nanofibre yarn.
Facile green synthesis of palladium quantum dots@carbon on mixed valence cerium oxide/graphene hybrid nanostructured bifunctional catalyst for electrocatalysis of alcohol and water
Authors: Kannan Ramanujam , Jang Hye-Ri , Yoo Eun-Sil , Lee Hong-Ki , Yoo Dong Jin
Published: April 2015

Electrocatalytic oxidation of ethylene glycol at Pd quantum dots@C–CeOx/RGO electrode.
Designing environmentally benign modified silica resin coatings with biomimetic textures for antibiofouling
Authors: Chen Zifei , Zhao Wenjie , Xu Jihai , Mo Mengting , Peng Shusen , Zeng Zhixiang , Wu Xuedong , Xue Qunji
Published: April 2015

Siloxane modified acrylic resin coatings with positive and negative replication textures were successfully fabricated by biomimicking the surface structures of natural lotus leaf and white crab shell via a replication method.
Biosynthesis of trioxacarcin revealing a different starter unit and complex tailoring steps for type II polyketide synthase
Authors: Zhang Mei , Hou Xian-Feng , Qi Li-Hua , Yin Yue , Li Qing , Pan Hai-Xue , Chen Xin-Ya , Tang Gong-Li
Published: April 2015

Different starter unit and complex tailoring steps for type II polyketide synthase in trioxacarcin biosynthesis.
The role of solvent swelling in the self-assembly of squalene based nanomedicines
Authors: Saha Debasish , Testard Fabienne , Grillo Isabelle , Zouhiri Fatima , Desmaele Didier , Radulescu Aurel , Desert Sylvain , Brulet Annie , Couvreur Patrick , Spalla Olivier
Published: April 2015

Squalene based nanoparticles obtained via nanoprecipitation are promising candidates as efficient anti-cancer drugs.
3D graphene/nylon rope as a skeleton for noble metal nanocatalysts for highly efficient heterogeneous continuous-flow reactions
Authors: Zhang Sai , Shen Xuetao , Zheng Zhiping , Ma Yuanyuan , Qu Yongquan
Published: April 2015

A universal approach has been developed to synthesize flexible and stable 3D noble metal/graphene/nylon rope catalysts, which realize their highly efficient and stable catalytic activity for heterogeneous continuous-flow reactions.
Toward “rocking-chair type” Mg–Li dual-salt batteries
Authors: Ichitsubo Tetsu , Okamoto Shinya , Kawaguchi Tomoya , Kumagai Yu , Oba Fumiyasu , Yagi Shunsuke , Goto Natsumi , Doi Takayuki , Matsubara Eiichiro
Published: April 2015

This work is devoted to fundamental electrochemistry on a novel concept of rechargeable battery, "rocking-chair type" Mg–Li dual-salt battery, in which both Mg and Li cations are carrier ions.
Autophagy as the effector and player in DNA damage response of cells to genotoxicants
Authors: Zhang Shi-Meng , Shang Zeng-Fu , Zhou Ping-Kun
Published: April 2015

In this review, we provide an overview and discuss the molecular mechanism of DNA damage induced autophagy, and their mutual regulation and its role in cell fate determination in response to genotoxic effects of environmental toxicants.
Fuzzy PI controlled inverter for grid interactive renewable energy systems
Authors: Sefa I. , Altin N. , Ozdemir S. , Kaplan O.
Published: April 2015

In this study, a fuzzy‐PI controlled grid interactive inverter has been designed and implemented. The proportional and integral gains of the PI controller are decided and tuned by the fuzzy logic controller (FLC) according to required operation point of the system. Thus, adaptive nature of the FLC and robust structure of the PI controller are synthesised. Eventually, an adaptive PI controller which can adopt changes because of different operation conditions, grid disturbances and natural effects with fast transient response is obtained. Simulation studies are validated with experimental results. Both simulation and experimental results show that proposed system has fast dynamic response and tracks reference current with a low overshot and short settling time. In addition, the waveform of the inverter output current is sinusoidal and also the current is in same phase and frequency with the line voltage. Furthermore, the total harmonic distortion level of the inverter current meets the international standards. In addition, the proposed inverter system is compared with conventional PI controlled grid interactive inverter with various proportional and integral gains.
Direct current injection and thermocapillary flow for purification of aligned arrays of single-walled carbon nanotubes
Authors: Xie Xu , Wahab Muhammad A. , Li Yuhang , Islam Ahmad E. , Tomic Bojan , Huang Jiyuan , Burns Branden , Seabron Eric , Dunham Simon N. , Du Frank , Lin Jonathan , Wilson William L. , Song Jizhou , Huang Yonggang , Alam Muhammad A. , Rogers John A.
Published: April 2015

Aligned arrays of semiconducting single-walled carbon nanotubes (s-SWNTs) represent ideal configurations for use of this class of material in high performance electronics. Development of means for removing the metallic SWNTs (m-SWNTs) in as-grown arrays represents an essential challenge. Here, we introduce a simple scheme that achieves this type of purification using direct, selective current injection through interdigitated electrodes into the m-SWNTs, to allow their complete removal using processes of thermocapillarity and dry etching. Experiments and numerical simulations establish the fundamental aspects that lead to selectivity in this process, thereby setting design rules for optimization. Single-step purification of arrays that include thousands of SWNTs demonstrates the effectiveness and simplicity of the procedures. The result is a practical route to large-area aligned arrays of purely s-SWNTs with low-cost experimental setups.
Correlation between thermal fluctuation effects and phase coherence factor in carrier transport of single-crystal organic semiconductors
Authors: Fukami Tatsuya , Ishii Hiroyuki , Kobayashi Nobuhiko , Uemura Takafumi , Sakai Kenichi , Okada Yugo , Takeya Jun , Hirose Kenji
Published: April 2015

We find that the phase coherence factor derived from Hall effect measurements of single-crystal thin-film field-effect transistors of pentacene, which relates the intrinsic charge transport with the phase coherence, has a strong correlation with the thermal fluctuations of transfer energies between neighboring molecules. This observation also holds true for other organic semiconductors such as tetracene, dianthrathiophene (DAT)-V, and dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DNTT). This gives us clues for constructing flexible molecular systems with high carrier mobility.
Solid-liquid interface free energies of pure bcc metals and B2 phases
Authors: Wilson S. R. , Gunawardana K. G. S. H. , Mendelev M. I.
Published: April 2015

The solid-liquid interface (SLI) free energy was determined from molecular dynamics (MD) simulation for several body centered cubic (bcc) metals and B2 metallic compounds (space group: Pm3̄m; prototype: CsCl). In order to include a bcc metal with a low melting temperature in our study, a semi-empirical potential was developed for Na. Two additional synthetic “Na” potentials were also developed to explore the effect of liquid structure and latent heat on the SLI free energy. The obtained MD data were compared with the empirical Turnbull, Laird, and Ewing relations. All three relations are found to predict the general trend observed in the MD data for bcc metals obtained within the present study. However, only the Laird and Ewing relations are able to predict the trend obtained within the sequence of “Na” potentials. The Laird relation provides the best prediction for our MD data and other MD data for bcc metals taken from the literature. Overall, the Laird relation also agrees well with our B2 data but requires a proportionality constant that is substantially different from the bcc case. It also fails to explain a considerable difference between the SLI free energies of some B2 phases which have nearly the same melting temperature. In contrast, this difference is satisfactorily described by the Ewing relation. Moreover, the Ewing relation obtained from the bcc dataset also provides a reasonable description of the B2 data.
The variational subspace valence bond method
Authors: Fletcher Graham D.
Published: April 2015

The variational subspace valence bond (VSVB) method based on overlapping orbitals is introduced. VSVB provides variational support against collapse for the optimization of overlapping linear combinations of atomic orbitals (OLCAOs) using modified orbital expansions, without recourse to orthogonalization. OLCAO have the advantage of being naturally localized, chemically intuitive (to individually model bonds and lone pairs, for example), and transferrable between different molecular systems. Such features are exploited to avoid key computational bottlenecks. Since the OLCAO can be doubly occupied, VSVB can access very large problems, and calculations on systems with several hundred atoms are presented.
Temperature dependence of post-sintered annealing on magnetic properties of intergranular phase in Nd-Fe-B permanent magnet
Authors: Yasui Akira , Nakamura Tetsuya , Kotani Yoshinori , Fukagawa Tomoki , Nishiuchi Takeshi , Hirosawa Satoshi
Published: April 2015

Post-sinter-annealing temperature (Ta) dependences of the chemical and magnetic properties of intergranular (grain boundary; GB) phase in a Nd14.0Fe79.7B6.2Cu0.1 sintered magnet have been investigated by x-ray absorption spectroscopy and its magnetic circular dichroism. A relative change of the Cu concentration in the GB phase is found to depend on Ta and shows the maximum at Ta = 500 °C. The Ta-dependence of the Cu concentration was very similar to that of the coercivity. On the other hand, there is no significant Ta-dependence for the magnetization at the fracture surface: the Fe magnetic moment is 1.7 ± 0.036 μB at all Ta. The Cu-rich layer segregated in the GB phase would have a key role in the coercivity enhancement of the Nd-Fe-B sintered magnet.
Kinetic effects on geodesic acoustic mode from combined collisions and impurities
Authors: Yang Shangchuan , Xie Jinlin , Liu Wandong
Published: April 2015

The dispersion relation for geodesic acoustic mode (GAM) is derived by applying a gyrokinetic model that accounts for the effects from both collisions and impurities. Based on the dispersion relation, an analysis is performed for the non-monotonic behavior of GAM damping versus the characteristic collision rate at various impurity levels. As the effective charge increases, the maximum damping rate is found to shift towards lower collision rates, nearer to the parameter range of a typical tokamak edge plasma. The relative strengths of ion-ion and impurity-induced collision effects, which are illustrated by numerical calculations, are found to be comparable. Impurity-induced collisions help decrease the frequency of GAM, while their effects on the damping rate are non-monotonic, resulting in a weaker total damping in the high collision regime. The results presented suggest considering collision effects as well as impurity effects in GAM analysis.
Thermal transport across graphene and single layer hexagonal boron nitride
Authors: Zhang Jingchao , Hong Yang , Yue Yanan
Published: April 2015

As the dimensions of nanocircuits and nanoelectronics shrink, thermal energies are being generated in more confined spaces, making it extremely important and urgent to explore for efficient heat dissipation pathways. In this work, the phonon energy transport across graphene and hexagonal boron-nitride (h-BN) interface is studied using classic molecular dynamics simulations. Effects of temperature, interatomic bond strength, heat flux direction, and functionalization on interfacial thermal transport are investigated. It is found out that by hydrogenating graphene in the hybrid structure, the interfacial thermal resistance (R) between graphene and h-BN can be reduced by 76.3%, indicating an effective approach to manipulate the interfacial thermal transport. Improved in-plane/out-of-plane phonon couplings and broadened phonon channels are observed in the hydrogenated graphene system by analyzing its phonon power spectra. The reported R results monotonically decrease with temperature and interatomic bond strengths. No thermal rectification phenomenon is observed in this interfacial thermal transport. Results reported in this work give the fundamental knowledge on graphene and h-BN thermal transport and provide rational guidelines for next generation thermal interface material designs.
Complexity extraction of electroencephalograms in Alzheimer's disease with weighted-permutation entropy
Authors: Deng Bin , Liang Li , Li Shunan , Wang Ruofan , Yu Haitao , Wang Jiang , Wei Xile
Published: April 2015

In this paper, weighted-permutation entropy (WPE) is applied to investigating the complexity abnormalities of Alzheimer's disease (AD) by analyzing 16-channel electroencephalograph (EEG) signals from 14 severe AD patients and 14 age-matched normal subjects. The WPE values are estimated in the delta, the theta, the alpha, and the beta sub-bands for each channel with an overlapped sliding window. WPE is modified from the permutation entropy (PE), which has been recently suggested as a measurement to extract the complexity of the EEG signals. The advantage of WPE over PE is verified by both the model simulated and the experimental EEG signals. Although the results show that both the average PE and WPE of AD patients are decreased in contrast with the normal group in these four sub-bands, especially in the theta band, WPE can exhibit a better performance in distinguishing the AD patients from the normal controls by the more significant differences in the four sub-bands, which may be attributed to the brain dysfunction. Thus, it suggests that WPE may become a probable useful tool to detect brain dysfunction in AD and it seems to be promising to disclose the abnormalities of brain activity for other neural disease.
Vibrational spectra and lattice thermal conductivity of kesterite-structured Cu2ZnSnS4 and Cu2ZnSnSe4
Authors: Skelton Jonathan M. , Jackson Adam J. , Dimitrievska Mirjana , Wallace Suzanne K. , Walsh Aron
Published: April 2015

Cu2ZnSnS4 (CZTS) is a promising material for photovoltaic and thermoelectric applications. Issues with quaternary semiconductors include chemical disorder (e.g., Cu–Zn antisites) and disproportionation into secondary phases (e.g., ZnS and Cu2SnS3). To provide a reference for the pure kesterite structure, we report the vibrational spectra—including both infra-red and Raman intensities—from lattice-dynamics calculations using first-principles force constants. Three-phonon interactions are used to estimate phonon lifetimes (spectral linewidths) and thermal conductivity. CZTS exhibits a remarkably low lattice thermal conductivity, competitive with high-performance thermoelectric materials. Transition from the sulfide to selenide (Cu2ZnSnSe4) results in softening of the phonon modes and an increase in phonon lifetimes.
Evaluation of the Kirkwood approximation for the diffusivity of channel-confined DNA chains in the de Gennes regime
Authors: Jain Aashish , Dorfman Kevin D.
Published: April 2015

We use Brownian dynamics with hydrodynamic interactions to calculate both the Kirkwood (short-time) diffusivity and the long-time diffusivity of DNA chains from free solution down to channel confinement in the de Gennes regime. The Kirkwood diffusivity in confinement is always higher than the diffusivity obtained from the mean-squared displacement of the center-of-mass, as is the case in free solution. Moreover, the divergence of the local diffusion tensor, which is non-zero in confinement, makes a negligible contribution to the latter diffusivity in confinement. The maximum error in the Kirkwood approximation in our simulations is about 2% for experimentally relevant simulation times. The error decreases with increasing confinement, consistent with arguments from blob theory and the molecular-weight dependence of the error in free solution. In light of the typical experimental errors in measuring the properties of channel-confined DNA, our results suggest that the Kirkwood approximation is sufficiently accurate to model experimental data.
Cattaneo-Christov heat flux model for rotating flow and heat transfer of upper-convected Maxwell fluid
Authors: Mustafa Meraj
Published: April 2015

In this paper Cattaneo-Christov heat flux model is used to investigate the rotating flow of viscoelastic fluid bounded by a stretching surface. This model is a modified version of the classical Fourier’s law that takes into account the interesting aspect of thermal relaxation time. The boundary layer equations are first modeled and then reduced to self-similar forms via similarity approach. Both analytical and numerical solutions are obtained and found in excellent agreement. Our computations reveal that velocity is inversely proportional to the viscoelastic fluid parameter. Further fluid temperature has inverse relationship with the relaxation time for heat flux and with the Prandtl number. Present consideration even in the case of Newtonian fluid does not yet exist in the literature.
Reproductive capacity of a marine species (Octopus tetricus) within a recent range extension area
Authors: Ramos Jorge E. , Pecl Gretta T. , Semmens Jayson M. , Strugnell Jan M. , León Rafael I. , Moltschaniwskyj Natalie A.
Published: April 2015

To persist in the face of environmental change, species must adjust to the new conditions or change their geographical distribution, e.g. by range extension. Success for individuals within a zone of range extension requires the new environment to support their capacity to produce viable gametes and survival of the offspring. Reproductive characteristics of the polewards range-shifting Octopus tetricus were examined within the new range off north-eastern Tasmania, Australia, to assess whether it is likely to successfully establish in this extended area of its range. Approximately 44% of captured males and 14% of captured females were mature. Mature females with developing eggs were found throughout the year. Greater numbers of mature females were observed during the austral summer and spring, whereas mature males were observed all year round. Fecundity was high and developing embryos appeared to be viable. Our results suggest that O. tetricus is successfully reproducing beyond its historical range, the reproductive cycle is timed to favourable environmental conditions, and the population has the potential to be self-sustainable. The reproductive biology of O. tetricus may thus facilitate the establishment and prevalence of the population into new environments beyond the known historical distribution.
In vivo characterization of chronic traumatic encephalopathy using [F-18]FDDNP PET brain imaging
Authors: Barrio Jorge R. , Small Gary W. , Wong Koon-Pong , Huang Sung-Cheng , Liu Jie , Merrill David A. , Giza Christopher C. , Fitzsimmons Robert P. , Omalu Bennet , Bailes Julian , Kepe Vladimir
Published: April 2015

Significance

Mild traumatic brain injuries are frequent events in the general population and are associated with a severe neurodegenerative disease, chronic traumatic encephalopathy (CTE). This disease is characterized by abnormal accumulation of protein aggregates, primarily tau proteins, which accumulate in brain areas responsible for mood, fear, stress, and cognition. There is no definitive clinical diagnosis of CTE at the present time, and this new work shows how a tau-sensitive brain imaging agent, [F-18]FDDNP, may be able to detect the disease in living people with varying degrees of symptoms. Early detection would facilitate the most effective management strategies and provide a baseline to measure the effectiveness of treatments.
Structural basis for substrate specificity of an amino acid ABC transporter
Authors: Yu Jie , Ge Jingpeng , Heuveling Johanna , Schneider Erwin , Yang Maojun
Published: April 2015

Significance

Here we report the crystal structures of an amino acid ATP-binding cassette (ABC) importer either in its apo form or in complex with substrates (Arg, His) and/or ATPs. Interestingly, each transmembrane domain has a negatively charged pocket, allowing amino acids carrying positively charged groups to pass through. Functional analyses of the transporter in proteoliposomes indicate its capability to undergo substrate-dependent conformational changes resulting in stimulated ATPase activity. Taken together, we identified a previously undefined substrate binding mode of ABC transporters and shed light on the mechanism underlying how ABC transporters select and translocate their substrates.
Evolution of the rapidly mutating human salivary agglutinin gene (
DMBT1
) and population subsistence strategy
Authors: Polley Shamik , Louzada Sandra , Forni Diego , Sironi Manuela , Balaskas Theodosius , Hains David S. , Yang Fengtang , Hollox Edward J.
Published: April 2015

Significance

Humans have undergone an evolutionary very recent change in environment of their own making. The development of agriculture profoundly altered diet and exposure to pathogens, and yet the evolutionary response to this is still poorly understood. Here, we characterize extensive copy number variation (CNV) of the gene encoding salivary agglutinin (deleted in malignant brain tumors 1,
DMBT1
). Salivary agglutinin comprises 10% of salivary protein and binds bacteria, including mediating the attachment of the causative agent of dental caries,
Streptococcus mutans
, to teeth. We show that
DMBT1
is a very fast-mutating protein-coding locus, and
DMBT1
CNV correlates with a population history of agriculture. Furthermore, we examine the relationship between variation of the
S. mutans
region that binds salivary agglutinin and CNV of the
DMBT1
gene.
Sall4-Gli3
system in early limb progenitors is essential for the development of limb skeletal elements
Authors: Akiyama Ryutaro , Kawakami Hiroko , Wong Julia , Oishi Isao , Nishinakamura Ryuichi , Kawakami Yasuhiko
Published: April 2015

Significance

The limb skeletal elements that have unique morphology and distinct locations are developed from limb progenitors, derived from the lateral plate mesoderm. These skeletal elements arise during limb development. In this study, we show genetic evidence that function of
Sall4
is essential prior to limb outgrowth for development of the anterior-proximal skeletal elements. Furthermore, genetic interaction between
Sall4
and
Gli3
is upstream of establishing
Shh
(Sonic hedgehog) expression, and therefore,
Shh
-dependent posterior skeletal elements. Our study identified early requirements of the
Sall4-Gli3
system for two putative progenitor pools that develop into distinct sets of limb skeletal elements.
General and condition-specific essential functions of
Pseudomonas aeruginosa
Authors: Lee Samuel A. , Gallagher Larry A. , Thongdee Metawee , Staudinger Benjamin J. , Lippman Soyeon , Singh Pradeep K. , Manoil Colin
Published: April 2015

Significance

There is an urgent need for new antibiotics active against resistant bacterial pathogens like
Pseudomonas aeruginosa
. Target-directed drug development provides a potential path to such drugs, and essential gene products represent potential targets. Accordingly, the work reported here defines a highly verified set of such functions for
P. aeruginosa
required for growth under a variety of different conditions.
Female peers in small work groups enhance women's motivation, verbal participation, and career aspirations in engineering
Authors: Dasgupta Nilanjana , Scircle Melissa McManus , Hunsinger Matthew
Published: April 2015

Significance

Advances in science, technology, engineering, and mathematics are critical to the American economy and require a robust workforce. The scarcity of women in this workforce is a well-recognized problem, but data-driven solutions to this problem are less common. We provide experimental evidence showing that gender composition of small groups in engineering has a substantial impact on undergraduate women’s persistence. Women participate more actively in engineering groups when members are mostly female vs. mostly male or in equal gender proportions. Women feel less anxious in female-majority groups vs. minority groups, especially as first-year students. Gender-parity groups are less effective than female-majority groups in promoting verbal participation. Female peers protect women’s confidence and engineering career aspirations despite masculine stereotypes about engineering.
fMRI of the rod scotoma elucidates cortical rod pathways and implications for lesion measurements
Authors: Barton Brian , Brewer Alyssa A.
Published: April 2015

Significance

We use functional MRI to investigate the cortical effects on V1, V2, V3, hV4, and VO-1 when humans’ eyes have adapted to low-light vision. We show that populations of neurons with receptive fields interacting with the central rod scotoma are silenced because of lack of stimulation, shift their locations ectopically, and/or scale their sizes in some maps because of partial stimulation when the receptive fields overlap with the rod scotoma. These same effects have been cited as hallmarks of long-term reorganization, but our results show that these effects can be the result of the normal short-term adaptation of the visual system. In contrast, we observe no cortical differences between general rod and cone input other than rod scotoma effects.
Asphyxia-activated corticocardiac signaling accelerates onset of cardiac arrest
Authors: Li Duan , Mabrouk Omar S. , Liu Tiecheng , Tian Fangyun , Xu Gang , Rengifo Santiago , Choi Sarah J. , Mathur Abhay , Crooks Charles P. , Kennedy Robert T. , Wang Michael M. , Ghanbari Hamid , Borjigin Jimo
Published: April 2015

Significance

How does the heart of a healthy individual cease to function within just a few minutes in the absence of oxygen? We addressed this issue by simultaneously examining the heart and the brain in animal models during asphyxiation and found that asphyxia markedly stimulates neurophysiological and neurochemical activities of the brain. Furthermore, previously unidentified corticocardiac coupling showed increased intensity as the heart deteriorated. Blocking efferent input to the heart markedly increased survival time of both the heart and the brain. The results show that targeting the brain’s outflow may be an effective strategy to delay the death of the heart and the brain from asphyxia.
Stress sigma factor RpoS degradation and translation are sensitive to the state of central metabolism
Authors: Battesti Aurelia , Majdalani Nadim , Gottesman Susan
Published: April 2015

Significance

Bacteria such as
Escherichia coli
encounter multiple environments and, as with all organisms, must balance growth and survival when conditions are suboptimal.
E. coli
uses the RpoS sigma factor, a specialized subunit of RNA polymerase, under conditions of stress or starvation to change the transcriptional program to one that promotes survival. We find that a block in central metabolism, via deletion of a gene encoding pyruvate dehydrogenase, leads to a dramatic increase in RpoS in exponential phase cells. This metabolic cue is likely via reduced amounts of acetyl-CoA. The increase in RpoS is mediated by stabilization of RpoS protein and by translational up-regulation of RpoS synthesis and links this stress response to the state of central metabolism.
Effect of kumquat (Fortunella crassifolia) pericarp on natural killer cell activity in vitro and in vivo
Authors: Nagahama Kiyoko , Eto Nozomu , Shimojo Tomofumi , Kondoh Tomomi , Nakahara Keiko , Sakakibara Yoichi , Fukui Keiichi , Suiko Masahito
Published: April 2015

Natural killer (NK) cells play a key role in innate immune defense against infectious disease and cancer. A reduction of NK activity is likely to be associated with increased risk of these types of disease. In this study, we investigate the activation potential of kumquat pericarp acetone fraction (KP-AF) on NK cells. It is shown to significantly increase IFN-γ production and NK cytotoxic activity in human KHYG-1 NK cells. Moreover, oral administration of KP-AF significantly improves both suppressed plasma IFN-γ levels and NK cytotoxic activity per splenocyte in restraint-stressed mice. These results indicate that raw kumquat pericarp activates NK cells in vitro and in vivo. To identify the active constituents, we also examined IFN-γ production on KHYG-1 cells by the predicted active components. Only β-cryptoxanthin increased IFN-γ production, suggesting that NK cell activation effects of KP-AF may be caused by carotenoids such as β-cryptoxanthin.
Transcellular delivery of vesicular SOCS proteins from macrophages to epithelial cells blunts inflammatory signaling
Authors: Bourdonnay Emilie , Zasłona Zbigniew , Penke Loka Raghu Kumar , Speth Jennifer M. , Schneider Daniel J. , Przybranowski Sally , Swanson Joel A. , Mancuso Peter , Freeman Christine M. , Curtis Jeffrey L. , Peters-Golden Marc
Published: April 2015

JAK-STAT signaling mediates the actions of numerous cytokines and growth factors, and its endogenous brake is the family of SOCS proteins. Consistent with their intracellular roles, SOCS proteins have never been identified in the extracellular space. Here we report that alveolar macrophages can secrete SOCS1 and -3 in exosomes and microparticles, respectively, for uptake by alveolar epithelial cells and subsequent inhibition of STAT activation. Secretion is tunable and occurs both in vitro and in vivo. SOCS secretion into lung lining fluid was diminished by cigarette smoking in humans and mice. Secretion and transcellular delivery of vesicular SOCS proteins thus represent a new model for the control of inflammatory signaling, which is subject to dysregulation during states of inflammation.
EBSeq-HMM: a Bayesian approach for identifying gene-expression changes in ordered RNA-seq experiments
Authors: Leng Ning , Li Yuan , McIntosh Brian E. , Nguyen Bao Kim , Duffin Bret , Tian Shulan , Thomson James A. , Dewey Colin N. , Stewart Ron , Kendziorski Christina
Published: April 2015

Motivation: With improvements in next-generation sequencing technologies and reductions in price, ordered RNA-seq experiments are becoming common. Of primary interest in these experiments is identifying genes that are changing over time or space, for example, and then characterizing the specific expression changes. A number of robust statistical methods are available to identify genes showing differential expression among multiple conditions, but most assume conditions are exchangeable and thereby sacrifice power and precision when applied to ordered data.

Results: We propose an empirical Bayes mixture modeling approach called EBSeq-HMM. In EBSeq-HMM, an auto-regressive hidden Markov model is implemented to accommodate dependence in gene expression across ordered conditions. As demonstrated in simulation and case studies, the output proves useful in identifying differentially expressed genes and in specifying gene-specific expression paths. EBSeq-HMM may also be used for inference regarding isoform expression.

Availability and implementation: An R package containing examples and sample datasets is available at Bioconductor.

Contact:  kendzior@biostat.wisc.edu

Supplementary information:  Supplementary data are available at Bioinformatics online.
Diagnosis of Sport Concussion
Authors: Brody David L
Published: April 2015

This chapter discusses diagnosis of concussion in the context of sport. In the setting of a sporting event, it is highly likely that the event itself and its effects on the patient will have been directly witnessed. The chapter recommends obtaining a collateral source history from those who actually observed the event—for example, coaches, teachers, parents, and teammates. The chapter recommends using the Sport Concussion Assessment Tool—3rd Edition (SCAT3) to guide a standard acute evaluation of sport-related concussion.
Sleep Disruption
Authors: Brody David L
Published: April 2015

You have to get this right; everything else hinges on it. The patient will get worse over time, not better, if they accumulate more and more sleep deficit from chronic insomnia. The hierarchy for sleep is as follows: Best is good quality natural sleep, second best is pharmacologically enhanced good quality sleep, worst is insufficient or poor quality sleep. The tools: sleep hygiene; pain control; psychological counseling and training, for example, cognitive behavioral therapy for insomnia; and sleep medications such as zolpidem (Ambien), Eszopiclone (Lunesta) Melatonin, and trazodone, which are helpful and relatively safe in concussion patients. Avoid whenever possible medications that can impair recovery and cognitive function, such as benzodiazepines, anticholinergics, antipsychotics, and alcohol as a sleep aide. If there are concerns, refer to a sleep medicine clinic for consultation and a formal sleep study; patients may not be reliable historians with regard to their own sleep habits.
Anxiety and Depression
Authors: Brody David L
Published: April 2015

First, assess safety. Severe anxiety and depression can lead to suicide. Second, distinguish between reactive anxiety and depressive symptoms versus an impairing mood disorder. The “treatment” for reactive anxiety and depressive symptoms is education, reassurance, and a good plan to get the patient’s life back on track. If the patient has an impairing (but not immediately dangerous) mood disorder, it can be treated for the most part just like a mood disorder in the absence of concussion. The optimal approach usually involves both nonpharmacological and pharmacological interventions: exercise, treat sleep disturbances, psychological counseling, avoid substances that worsen mood overall such as alcohol and street drugs, consider appropriate long-term antidepressant/antianxiety medications. There are many options, but fluoxetine (Prozac) and venlafaxine (Effexor) may be good choices for patients where low energy is more concerning than anxiety, whereas paroxetine (Paxil) or sertraline (Zoloft) may be preferred when anxiety is a major component.
Memory Impairment
Authors: Brody David L
Published: April 2015

Many complaints of memory problems after concussion actually turn out to be attention deficit. Take a careful collateral history regarding memory function in everyday life. Consider both bedside testing and formal neuropsychological testing of memory, but treat the patient, not the test results. Reduce barriers to optimal memory function: Optimize sleep; treat chronic pain; taper or stop cognitively impairing medications; stop alcohol and illicit drugs; prescribe moderate cardiovascular exercise; test for vitamin B12 deficiency, hypothyroidism, electrolyte disorders, hypo- or hypergylcemia, renal failure, liver failure, and anemia. Refer to speech therapy and occupational therapy for memory training. Stimulants can allow more intense cognitive rehabilitation when attention or fatigue are limiting. Consider pharmacological enhancers of memory including caffeine, donepezil, or rivastigmine. These have modest benefits, and the nonpharmacological interventions are more important.
Executive Dysfunction
Authors: Brody David L
Published: April 2015

Problems with organization, planning, strategy decisions, mental flexibility, optimizing risk/reward relationships, prioritizing, and goal setting are often called executive dysfunction. Collateral history and neuropsychological testing will help sort out the nature of the impairment, but treat the patient, not the test results. Reduce barriers to optimal cognitive function: Optimize sleep; treat chronic pain; taper or stop cognitively impairing medications; stop alcohol and illicit drugs; prescribe moderate cardiovascular exercise; refer to speech therapy and occupational therapy for executive function training. There are no specific pharmacological treatments for executive function. Consider trials of caffeine, stimulants, donepezil or rivastigmine, modafinil, or dopaminergic agents.
Seizures
Authors: Brody David L
Published: April 2015

Concussion rarely causes recurrent seizures. A patient with a brief seizure that occurs within the first 30 minutes of concussion does not need to be treated with antiepileptics or have driving restrictions. However, a seizure occurring later than 30 minutes after the injury, a seizure that lasts more than one minute, or a seizure after concussion in a patient with a previous seizure disorder requires a different approach. Consider hospital observation, brain MRI, EEG, laboratory studies, assessment for infection, and a screen for drug and alchohol use or withdrawal. If seizures need to be treated, often the best approach includes mood stabilizing medications with minimal cognitively impairing side effects. An oxcarbazepine (Trileptal) bridge during lamotrigine (Lamictal) titration is a reasonable choice. Carbamazepine generic is a good option when cost is an issue.
Return to Contact Sports
Authors: Brody David L
Published: April 2015

Published guidelines on return to play apply to simple concussions: (1) No return to play in the same 24-hour period as the concussion. (2) Graded, stepwise increases in activity guided by symptoms over 6–10 days. (3) No difference in return to play for elite versus nonelite athletes. (4) Brief convulsions or posturing at the time of concussion does not indicate higher than normal risk of seizures and requires no specific management. For more complex concussions, discourage the patient from returning to contact sports until all of the following are true: The symptoms are all in the mild range or resolved, the collateral source verifies that the patient’s behavior is back to normal, the patient has been able to successfully return to school or work, balance is back to normal, and the patient passes a physical therapist-directed moderate exercise test.
When Is It Safe to Fly or Travel to High Altitude?
Authors: Brody David L
Published: April 2015

Most commercial airplanes are pressurized to the equivalent of about 7,000–8,000 feet. United States Air Force researchers have shown that uninjured people have very little change in cognitive function or symptoms at this altitude, but that this is not the case after concussion. Symptoms and deficits that had resolved can come back at altitude, most notably headaches, slowing of cognitive performance, and impaired balance. Inform the patient and family about this risk and then let them make their own decisions about whether it is worth it. There is no evidence of permanent harm from flying or traveling to moderate altitude in concussion patients, but it has not been carefully studied.
Special Topics in Adolescents
Authors: Brody David L
Published: April 2015

Adolescents may be less able to make good judgments about their own abilities than adults. The collateral source becomes even more important than usual. Address questions about drug and alchohol use privately and give advice without the parents present. Peer influences may have a big impact on decision-making. Obtain collateral history from peers and educate peers as well as parents. Preexisting attention deficit, learning disabilities, and mood instability can get substantially worse after concussion and may require intensified treatment. For patients at the cusp of starting to drive, consider advising extra caution: go back to the beginning of driver’s education and get a professional driving evaluation. Consider preemptively addressing questions that the adolescent may be afraid to ask or cannot formulate accurately.
Special Topics in Contact Sport Athletes and Others with Multiple Concussions
Authors: Brody David L
Published: April 2015

This chapter considers issues in patients with multiple concussions. These patients must consider when to retire from contact sports. Help the patient, family, and peers think through the decision carefully. Educate them about the risk of serious and currently untreatable long-term problems such as chronic traumatic encephalopathy (CTE). Discuss potential for a future professional sports career versus other career as well as interpersonal and family aspirations. Patients want to know if they have CTE. There is no way to tell for sure while they are alive. High-risk features may include progressive worsening over time, prominent mood and behavioral abnormalities, parkinsonism, and a cavum septum pellucidum on MRI scan. Treatment is entirely based on relieving symptoms and keeping the patient safe.
A New Strategy to Combat Hospital Infections
Authors: Saint Sanjay
Published: April 2015

Healthcare-associated infection (HAI) takes a heavy toll on patients, and negatively affects hospitals themselves, both financially and psychologically. Proven technical approaches to prevent infection have often faltered because of the failure of hospital staff to adopt them. As the chapter explains, the book focuses on these adaptive problems, particularly as experienced during efforts to combat catheter-associated urinary tract infection (CAUTI), central line-associated bloodstream infection (CLABSI), and ventilator-associated pneumonia (VAP). It provides a step-by-step description of a model quality improvement intervention, explaining why clinicians neglect or actively oppose such initiatives and how to change their minds. CAUTI has proven far more resistant to quality improvement efforts than VAP or CLABSI and thus serves as the primary model for intervention. The CAUTI intervention framework is also broadly applicable to a variety of other hospital issues including preventing falls and Clostridium difficile infection. The solutions presented grow out of the extensive research by the authors and their colleagues at the University of Michigan and VA Ann Arbor Healthcare System.
Committing to an Infection Prevention Initiative
Authors: Saint Sanjay
Published: April 2015

What motivates a hospital administration to take on an infection prevention initiative? It may simply reflect a hospital’s culture of excellence, a commitment to patient safety, though that may be combined with a determination to keep up with competing institutions or to avoid federal financial penalties. Quality improvement initiatives can drain staff time and energy but save substantial dollars in the long run. Once the decision to proceed with the CAUTI initiative is made at a model hospital, the leaders start a team-building process, choosing an executive sponsor with experience on the wards, the project’s main venue. The sponsor, in turn, selects a project manager, who will find physician and nurse champions to carry the goals and content of the initiative to the staff. The initiative calls for the adoption of a bundle of evidence-based behaviors—in this case, to reduce the unnecessary use of indwelling urinary catheters known as Foleys.
Databases, registries, and quality of care
Authors: Danchin Nicolas , Ecarnot Fiona , Schiele François
Published: April 2015

This chapter will describe what databases and registries can provide for clinicians and researchers. It will also describe the respective position of randomized clinical trials and databases/registries as complementary pillars of evidence-based medicine, and how they are of particular importance in the field of acute cardiac care. Finally, the importance of databases in quality of care processes will be discussed.
Cardiopulmonary resuscitation and the post-cardiac arrest syndrome
Authors: Nolan Jerry P
Published: April 2015

Cardiac arrest is the most extreme of medical emergencies. If the victim is to have any chance of high-quality neurological recovery, cardiac arrest must be diagnosed quickly, followed by summoning for help as basic life support (chest compressions and ventilations) is started. In most cases, the initial rhythm will be shockable, but this will have often deteriorated to a non-shockable rhythm by the time a monitor and/or defibrillator is applied. While basic life support will sustain some oxygen delivery to the heart and brain and will help to slow the rate of deterioration in these vital organs, it is important to achieve restoration of a spontaneous circulation as soon as possible (by defibrillation if the rhythm is shockable). Once return of spontaneous circulation is achieved, the quality of post-cardiac arrest management will influence the patient’s final neurological outcome. These interventions aim to restore myocardial function and minimize neurological injury.