bluuebunny/crossref_metadata_2025_split huggingface dataset:
Epilepsy and intellectual disability linked protein Shrm4 interaction with GABABRs shapes inhibitory neurotransmission
Authors: Zapata Jonathan , Moretto Edoardo , Hannan Saad , Murru Luca , Longatti Anna , Mazza Davide , Benedetti Lorena , Fossati Matteo , Heise Christopher , Ponzoni Luisa , Valnegri Pamela , Braida Daniela , Sala Mariaelvina , Francolini Maura , Hildebrand Jeffrey , Kalscheuer Vera , Fanelli Francesca , Sala Carlo , Bettler Bernhard , Bassani Silvia , Smart Trevor G. , Passafaro Maria 
Published: March 2017

AbstractShrm4, a protein expressed only in polarized tissues, is encoded by theKIAA1202gene, whose mutations have been linked to epilepsy and intellectual disability. However, a physiological role for Shrm4 in the brain is yet to be established. Here, we report that Shrm4 is localized to synapses where it regulates dendritic spine morphology and interacts with the C terminus of GABABreceptors (GABABRs) to control their cell surface expression and intracellular trafficking via a dynein-dependent mechanism. Knockdown of Shrm4 in rat severely impairs GABABR activity causing increased anxiety-like behaviour and susceptibility to seizures. Moreover, Shrm4 influences hippocampal excitability by modulating tonic inhibition in dentate gyrus granule cells, in a process involving crosstalk between GABABRs and extrasynaptic δ-subunit-containing GABAARs. Our data highlights a role for Shrm4 in synaptogenesis and in maintaining GABABR-mediated inhibition, perturbation of which may be responsible for the involvement of Shrm4 in cognitive disorders and epilepsy.
Disorder-induced single-mode transmission
Authors: Ruocco Giancarlo , Abaie Behnam , Schirmacher Walter , Mafi Arash , Leonetti Marco 
Published: March 2017

AbstractLocalized states trap waves propagating in a disordered potential and play a crucial role in Anderson localization, which is the absence of diffusion due to disorder. Some localized states are barely coupled with neighbours because of differences in wavelength or small spatial overlap, thus preventing energy leakage to the surroundings. This is the same degree of isolation found in the homogeneous core of a single-mode optical fibre. Here we show that localized states of a disordered optical fibre are single mode: the transmission channels possess a high degree of resilience to perturbation and invariance with respect to the launch conditions. Our experimental approach allows identification and characterization of the single-mode transmission channels in a disordered matrix, demonstrating low losses and densely packed single modes. These disordered and wavelength-sensitive channels may be exploited to de-multiplex different colours at different locations.
Correlation of fitness landscapes from three orthologous TIM barrels originates from sequence and structure constraints
Authors: Chan Yvonne H. , Venev Sergey V. , Zeldovich Konstantin B. , Matthews C. Robert 
Published: March 2017

AbstractSequence divergence of orthologous proteins enables adaptation to environmental stresses and promotes evolution of novel functions. Limits on evolution imposed by constraints on sequence and structure were explored using a model TIM barrel protein, indole-3-glycerol phosphate synthase (IGPS). Fitness effects of point mutations in three phylogenetically divergent IGPS proteins during adaptation to temperature stress were probed by auxotrophic complementation of yeast with prokaryotic, thermophilic IGPS. Analysis of beneficial mutations pointed to an unexpected, long-range allosteric pathway towards the active site of the protein. Significant correlations between the fitness landscapes of distant orthologues implicate both sequence and structure as primary forces in defining the TIM barrel fitness landscape and suggest that fitness landscapes can be translocated in sequence space. Exploration of fitness landscapes in the context of a protein fold provides a strategy for elucidating the sequence-structure-fitness relationships in other common motifs.
The role of anharmonic phonons in under-barrier spin relaxation of single molecule magnets
Authors: Lunghi Alessandro , Totti Federico , Sessoli Roberta , Sanvito Stefano 
Published: March 2017

AbstractThe use of single molecule magnets in mainstream electronics requires their magnetic moment to be stable over long times. One can achieve such a goal by designing compounds with spin-reversal barriers exceeding room temperature, namely with large uniaxial anisotropies. Such strategy, however, has been defeated by several recent experiments demonstrating under-barrier relaxation at high temperature, a behaviour today unexplained. Here we propose spin–phonon coupling to be responsible for such anomaly. With a combination of electronic structure theory and master equations we show that, in the presence of phonon dissipation, the relevant energy scale for the spin relaxation is given by the lower-lying phonon modes interacting with the local spins. These open a channel for spin reversal at energies lower than that set by the magnetic anisotropy, producing fast under-barrier spin relaxation. Our findings rationalize a significant body of experimental work and suggest a possible strategy for engineering room temperature single molecule magnets.
To address surface reaction network complexity using scaling relations machine learning and DFT calculations
Authors: Ulissi Zachary W. , Medford Andrew J. , Bligaard Thomas , Nørskov Jens K. 
Published: March 2017

AbstractSurface reaction networks involving hydrocarbons exhibit enormous complexity with thousands of species and reactions for all but the very simplest of chemistries. We present a framework for optimization under uncertainty for heterogeneous catalysis reaction networks using surrogate models that are trained on the fly. The surrogate model is constructed by teaching a Gaussian process adsorption energies based on group additivity fingerprints, combined with transition-state scaling relations and a simple classifier for determining the rate-limiting step. The surrogate model is iteratively used to predict the most important reaction step to be calculated explicitly with computationally demanding electronic structure theory. Applying these methods to the reaction of syngas on rhodium(111), we identify the most likely reaction mechanism. Propagating uncertainty throughout this process yields the likelihood that the final mechanism is complete given measurements on only a subset of the entire network and uncertainty in the underlying density functional theory calculations.
Synthesis and structures of gold and copper carbene intermediates in catalytic amination of alkynes
Authors: Wang Jiwei , Cao Xiaoming , Lv Shichang , Zhang Caiyun , Xu Sheng , Shi Min , Zhang Jun 
Published: March 2017

AbstractMetal carbenes are often proposed as reactive intermediates in the late transition metal-catalysed transformations of alkynes. Owing to their high reactivity, however, isolation and structural characterization of metal carbene intermediates in these transformations has remained unknown. Herein, we report the isolation of two acyclic gold and copper carbene intermediates in either Au(I)- or Cu(I)-catalysed cyclization of N-alkynyl formamidines through five-exo-dig cyclization. X-ray diffraction, 13C NMR spectra data and computational analyses provide evidence for the formation of a gold carbene intermediate with a carbocation-like electronic character. Using the intrinsic bond orbital (IBO) approach, we also evaluate the π-stabilizing effects of organic substituents at the carbene carbon atom in the gold carbene intermediate. Another rare six-membered copper carbene complex is also obtained through 6-endo-dig cyclization. These metal carbenes have proven reactive toward oxidation. The metal-promoted cyclization of N-alkynyl formamidine provides a facile approach to synthesize metal carbene species.
The SWI/SNF chromatin remodelling complex is required for maintenance of lineage specific enhancers
Authors: Alver Burak H. , Kim Kimberly H. , Lu Ping , Wang Xiaofeng , Manchester Haley E. , Wang Weishan , Haswell Jeffrey R. , Park Peter J. , Roberts Charles W. M. 
Published: March 2017

AbstractGenes encoding subunits of SWI/SNF (BAF) chromatin remodelling complexes are collectively altered in over 20% of human malignancies, but the mechanisms by which these complexes alter chromatin to modulate transcription and cell fate are poorly understood. Utilizing mouse embryonic fibroblast and cancer cell line models, here we show via ChIP-seq and biochemical assays that SWI/SNF complexes are preferentially targeted to distal lineage specific enhancers and interact with p300 to modulate histone H3 lysine 27 acetylation. We identify a greater requirement for SWI/SNF at typical enhancers than at most super-enhancers and at enhancers in untranscribed regions than in transcribed regions. Our data further demonstrate that SWI/SNF-dependent distal enhancers are essential for controlling expression of genes linked to developmental processes. Our findings thus establish SWI/SNF complexes as regulators of the enhancer landscape and provide insight into the roles of SWI/SNF in cellular fate control.
Geologically-inspired strong bulk ceramics made with water at room temperature
Authors: Bouville Florian , Studart André R. 
Published: March 2017

AbstractDense ceramic materials can form in nature under mild temperatures in water. By contrast, man-made ceramics often require sintering temperatures in excess of 1,400 °C for densification. Chemical strategies inspired by biomineralization processes have been demonstrated but remain limited to the fabrication of thin films and particles. Besides biomineralization, the formation of dense ceramic-like materials such as limestone also occurs in nature through large-scale geological processes. Inspired by the geological compaction of mineral sediments in nature, we report a room-temperature method to produce dense and strong ceramics within timescales comparable to those of conventional manufacturing processes. Using nanoscale powders and high compaction pressures, we show that such cold sintering process can be realized with water at room temperature to result in centimetre-sized bulk parts with specific strength that is comparable to, and occasionally even higher than, that of traditional structural materials like concrete.
Shock-transformation of whitlockite to merrillite and the implications for meteoritic phosphate
Authors: Adcock C. T. , Tschauner O. , Hausrath E. M. , Udry A. , Luo S. N. , Cai Y. , Ren M. , Lanzirotti A. , Newville M. , Kunz M. , Lin C. 
Published: March 2017

AbstractMeteorites represent the only samples available for study on Earth of a number of planetary bodies. The minerals within meteorites therefore hold the key to addressing numerous questions about our solar system. Of particular interest is the Ca-phosphate mineral merrillite, the anhydrous end-member of the merrillite–whitlockite solid solution series. For example, the anhydrous nature of merrillite in Martian meteorites has been interpreted as evidence of water-limited late-stage Martian melts. However, recent research on apatite in the same meteorites suggests higher water content in melts. One complication of using meteorites rather than direct samples is the shock compression all meteorites have experienced, which can alter meteorite mineralogy. Here we show whitlockite transformation into merrillite by shock-compression levels relevant to meteorites, including Martian meteorites. The results open the possibility that at least part of meteoritic merrillite may have originally been H+-bearing whitlockite with implications for interpreting meteorites and the need for future sample return.
Spin excitations and the Fermi surface of superconducting FeS
Authors: Man Haoran , Guo Jiangang , Zhang Rui , Schönemann Rico , Yin Zhiping , Fu Mingxuan , Stone Matthew B. , Huang Qingzhen , Song Yu , Wang Weiyi , Singh David J. , Lochner Felix , Hickel Tilmann , Eremin Ilya , Harriger Leland , Lynn Jeffrey W. , Broholm Collin , Balicas Luis , Si Qimiao , Dai Pengcheng 
Published: March 2017

AbstractHigh-temperature superconductivity occurs near antiferromagnetic instabilities and the nematic state. Debate remains on the origin of nematic order in FeSe and its relation with superconductivity. Here, we use transport, neutron scattering and Fermi surface measurements to demonstrate that hydrothermo grown superconducting FeS, an isostructure of FeSe, is a tetragonal paramagnet without nematic order and with a quasiparticle mass significantly reduced from that of FeSe. Only stripe-type spin excitations are observed up to 100 meV. No direct coupling between spin excitations and superconductivity in FeS is found, suggesting that FeS is less correlated and the nematic order in FeSe is due to competing checkerboard and stripe spin fluctuations.
Controllability and observability in complex networks – the effect of connection types
Authors: Leitold Dániel , Vathy-Fogarassy Ágnes , Abonyi János 
Published: March 2017

AbstractNetwork theory based controllability and observability analysis have become widely used techniques. We realized that most applications are not related to dynamical systems, and mainly the physical topologies of the systems are analysed without deeper considerations. Here, we draw attention to the importance of dynamics inside and between state variables by adding functional relationship defined edges to the original topology. The resulting networks differ from physical topologies of the systems and describe more accurately the dynamics of the conservation of mass, momentum and energy. We define the typical connection types and highlight how the reinterpreted topologies change the number of the necessary sensors and actuators in benchmark networks widely studied in the literature. Additionally, we offer a workflow for network science-based dynamical system analysis, and we also introduce a method for generating the minimum number of necessary actuator and sensor points in the system.
Human Corneal Endothelial Cell Cultivation From Old Donor Corneas With Forced Attachment
Authors: Parekh Mohit , Ahmad Sajjad , Ruzza Alessandro , Ferrari Stefano 
Published: March 2017

AbstractHuman corneal endothelial cells (HCEnCs) are responsible for maintaining the transparency of the cornea. Damaged or diseased HCEnCs may cause blindness. Replacement of the diseased cells with a healthy donor endothelium is the only currently available treatment. Tissue-engineering can serve as an alternative to conventional donor corneal transplantation. Due to the global shortage of donor corneas, a wide interest in the development of cultured graft substitutes and artificial corneas has increased. Availability of the old donor corneas is higher especially for research. Although it can be proposed as a valuable source for cell culture, its less proliferative capability emerges a challenge for the researchers. This article describes the use of hyaluronic acid (HA) in combination with Rho-kinase inhibitor (ROCK) Y-27632 for the cultivation of HCEnCs from older donor corneas (age > 60 years). Four conditions including and excluding HA + ROCK and its effect on early attachment rates and proliferation was studied on forty-eight corneas. It was observed that HCEnCs reach confluence within 10–15 days when cultured with HA + ROCK. This approach improves the efficiency of cell adhesion due to force attachment. HCEnCs from old donor corneas can be cultured using this method which may further lead to cell-based therapy for treating corneal endothelial dysfunction.
Selenocystine against methyl mercury cytotoxicity in HepG2 cells
Authors: Wang Han , Chen Beibei , He Man , Yu Xiaoxiao , Hu Bin 
Published: March 2017

AbstractMethyl mercury (MeHg) is a highly toxic substance and the effect of selenium against MeHg toxicity is a hot topic. Until now, no related works have been reported from the view of the point of elemental speciation which is promising to study the mechanism at the molecular level. In this work, to reveal the effect of selenocystine (SeCys2) against MeHg cytotoxicity in HepG2 cells, a comprehensive analytical platform for speciation study of mercury and selenium in MeHg incubated or MeHg and SeCys2 co-incubated HepG2 cells was developed by integrating liquid chromatography (LC) - inductively coupled plasma mass spectrometry (ICP-MS) hyphenated techniques and chip-based pretreatment method. Interesting phenomenon was found that the co-incubation of MeHg with SeCys2 promoted the uptake of MeHg in HepG2 cells, but reduced the cytotoxicity of MeHg. Results obtained by ICP-MS based hyphenated techniques revealed a possible pathway for the incorporation and excretion of mercury species with the coexistence of SeCys2. The formation of MeHg and SeCys2 aggregation promotes the uptake of MeHg; majority of MeHg transforms into small molecular complexes (MeHg-glutathione (GSH) and MeHg-cysteine (Cys)) in HepG2 cells; and MeHg-GSH is the elimination species which results in reducing the cytotoxicity of MeHg.
Unexpected friction behaviours due to capillary and adhesion effects
Authors: Guo Fei , Tian Yu , Liu Ying , Wang Yuming 
Published: March 2017

AbstractIn this present work, we show that pouring water into the interface of SiC sliding against the same SiC material makes the friction coefficient far exceed that governing initial dry friction, and a subsequent load increase causes a dramatic abnormal friction force decrease. With the load further increasing to a critical value, friction force sharply increases again. The small amounts of water in the interface generates a large capillary force, the capillary bridges break to cause micro-separation of interface increase to allow bulk water to enter the friction interface, and a squeezing out of the water film to form a strong adhesion force between SiC-SiC materials, are considered to be responsible for the three stages, respectively.
A selective and label-free strategy for rapid screening of telomere-binding Ligands via fluorescence regulation of DNA/silver nanocluster
Authors: Cheng Rui , Xu Jing , Zhang Xiafei , Shi Zhilu , Zhang Qi , Jin Yan 
Published: March 2017

AbstractHerein, the conformational switch of G-rich oligonucleotide (GDNA) demonstrated the obvious functional switch of GDNA which was found to significantly affect the fluorescence of the in-situ synthesized DNA/silver nanocluster (DNA-AgNC) in homogeneous solution. We envisioned that the allosteric interaction between GDNA and DNA-AgNC would be possible to be used for screening telomere-binding ligands. A unimolecular probe (12C5TG) is ingeniously designed consisting of three contiguous DNA elements: G-rich telomeric DNA (GDNA) as molecular recognition sequence, T-rich DNA as linker and C-rich DNA as template of DNA-AgNC. The quantum yield and stability of 12C5TG-AgNC is greatly improved because the nearby deoxyguanosines tended to protect DNA/AgNC against oxidation. However, in the presence of ligands, the formation of G-quadruplex obviously quenched the fluorescence of DNA-AgNC. By taking full advantage of intramolecular allosteric effect, telomere-binding ligands were selectively and label-free screened by using deoxyguanines and G-quadruplex as natural fluorescence enhancer and quencher of DNA-AgNC respectively. Therefore, the functional switching of G-rich structure offers a cost-effective, facile and reliable way to screen drugs, which holds a great potential in bioanalysis as well.
Comparison of different critical nitrogen dilution curves for nitrogen diagnosis in rice
Authors: Ata-Ul-Karim Syed Tahir , Zhu Yan , Liu Xiaojun , Cao Qiang , Tian Yongchao , Cao Weixing 
Published: March 2017

AbstractThe critical nitrogen (N) dilution curve is a suitable analytical tool for in-season estimation of N status to implement precision N management. This study was undertaken for a comprehensive comparison of N dilution curves in Japonica and Indica rice to investigate, whether a single curve can be used for both rice ecotypes and to determine the most robust plant index for assessing N status in rice ecotypes. The different N dilution curves were developed based on plant dry matter (PDM), leaf area index (LAI), leaf dry matter (LDM) and stem dry matter (SDM) for N diagnosis in Japonica and Indica rice. The comparison of N dilution curves of two rice ecotypes showed non-significant differences, therefore a single/unified curve can be used to assess plant N status for precision N management in both rice ecotypes. The relationships between PDM based, with LAI, LDM, and SDM based N nutrition index, accumulated N deficit and N requirement, indicated that leaf based approaches could be used as substitutes for PDM approach. The lower coefficient b values of LDM based curve (due to efficient physiological N use in leaves) implied that LDM was the most appropriate approach for developing N curve as compared to other approaches.
Scaling Law of Urban Ride Sharing
Authors: Tachet R. , Sagarra O. , Santi P. , Resta G. , Szell M. , Strogatz S. H. , Ratti C. 
Published: March 2017

AbstractSharing rides could drastically improve the efficiency of car and taxi transportation. Unleashing such potential, however, requires understanding how urban parameters affect the fraction of individual trips that can be shared, a quantity that we call shareability. Using data on millions of taxi trips in New York City, San Francisco, Singapore, and Vienna, we compute the shareability curves for each city, and find that a natural rescaling collapses them onto a single, universal curve. We explain this scaling law theoretically with a simple model that predicts the potential for ride sharing in any city, using a few basic urban quantities and no adjustable parameters. Accurate extrapolations of this type will help planners, transportation companies, and society at large to shape a sustainable path for urban growth.
ABO blood types associated with the risk of venous thromboembolism in Han Chinese people: A hospital-based study of 200,000 patients
Authors: Sun Xuefeng , Feng Jun , Wu Wei , Peng Min , Shi Juhong 
Published: March 2017

AbstractABO blood types are putatively associated with the risk of venous thromboembolism (VTE), but it is not proved in Chinese people. A large population of Han Chinese patients discharged from Peking Union Medical College Hospital between January 2010 and June 2016 were retrospectively analyzed in a case-control study. A total of 1412 VTE patients were identified from 200,660 discharged Han Chinese patients, including 600 patients with deep vein thrombosis (DVT), 441 patients with pulmonary embolism, and 371 patients with both DVT and pulmonary embolism. The prevalence of non-O blood type was weakly but statistically higher in VTE patients compared with 199,248 non-VTE patients, with an odds ratio (OR) of 1.362 (95% confidence interval [CI], 1.205–1.540). Subgroup analysis showed that the OR for non-O blood type was still increased. It was greater in pre-hospital VTE (OR = 1.464) than that in hospital-acquired VTE (OR = 1.224), and greater in unprovoked VTE (OR = 1.859) than that in provoked VTE (OR = 1.227). The OR for non-O blood type decreased with age in subgroup analysis. These results suggest a weak but statistically significant correlation between non-O blood type and risk of VTE in Han Chinese people.