bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tracking ocean heat uptake during the surface warming hiatus
Authors: Liu Wei , Xie Shang-Ping , Lu Jian 
Published: March 2016

AbstractOcean heat uptake is observed to penetrate deep into the Atlantic and Southern Oceans during the recent hiatus of global warming. Here we show that the deep heat penetration in these two basins is not unique to the hiatus but is characteristic of anthropogenic warming and merely reflects the depth of the mean meridional overturning circulation in the basin. We find, however, that heat redistribution in the upper 350 m between the Pacific and Indian Oceans is closely tied to the surface warming hiatus. The Indian Ocean shows an anomalous warming below 50 m during hiatus events due to an enhanced heat transport by the Indonesian throughflow in response to the intensified trade winds in the equatorial Pacific. Thus, the Pacific and Indian Oceans are the key regions to track ocean heat uptake during the surface warming hiatus.
A developmentally regulated switch from stem cells to dedifferentiation for limb muscle regeneration in newts
Authors: Tanaka Hibiki Vincent , Ng Nathaniel Chuen Yin , Yang Yu Zhan , Casco-Robles Martin Miguel , Maruo Fumiaki , Tsonis Panagiotis A. , Chiba Chikafumi 
Published: March 2016

AbstractThe newt, a urodele amphibian, is able to repeatedly regenerate its limbs throughout its lifespan, whereas other amphibians deteriorate or lose their ability to regenerate limbs after metamorphosis. It remains to be determined whether such an exceptional ability of the newt is either attributed to a strategy, which controls regeneration in larvae, or on a novel one invented by the newt after metamorphosis. Here we report that the newt switches the cellular mechanism for limb regeneration from a stem/progenitor-based mechanism (larval mode) to a dedifferentiation-based one (adult mode) as it transits beyond metamorphosis. We demonstrate that larval newts use stem/progenitor cells such as satellite cells for new muscle in a regenerated limb, whereas metamorphosed newts recruit muscle fibre cells in the stump for the same purpose. We conclude that the newt has evolved novel strategies to secure its regenerative ability of the limbs after metamorphosis.
Revealing the role of molecular rigidity on the fragility evolution of glass-forming liquids
Authors: Yildirim C. , Raty J.-Y. , Micoulaut M. 
Published: March 2016

AbstractIf quenched fast enough, a liquid is able to avoid crystallization and will remain in a metastable supercooled state down to the glass transition, with an important increase in viscosity upon further cooling. There are important differences in the way liquids relax as they approach the glass transition, rapid or slow variation in dynamic quantities under moderate temperature changes, and a simple means to quantify such variations is provided by the concept of fragility. Here, we report molecular dynamics simulations of a typical network-forming glass, Ge–Se, and find that the relaxation behaviour of the supercooled liquid is strongly correlated to the variation of rigidity with temperature and the spatial distribution of the corresponding topological constraints, which ultimately connect to the fragility minima. This permits extending the fragility concept to aspects of topology/rigidity, and to the degree of homogeneity of the atomic-scale interactions for a variety of structural glasses.
Perversions with a twist
Authors: Silva Pedro E. S. , Trigueiros Joao L. , Trindade Ana C. , Simoes Ricardo , Dias Ricardo G. , Godinho Maria Helena , de Abreu Fernao Vistulo 
Published: March 2016

AbstractPerversions connecting two helices with symmetric handedness are a common occurrence in nature, for example in tendrils. These defects can be found in our day life decorating ribbon gifts or when plants use tendrils to attach to a support. Perversions arise when clamped elastic filaments coil into a helical shape but have to conserve zero overall twist. We investigate whether other types of perversions exist and if they display different properties. Here we show mathematically and experimentally that a continuous range of different perversions can exist and present different geometries. Experimentally, different perversions were generated using micro electrospun fibres. Our experimental results also confirm that these perversions behave differently upon release and adopt different final configurations. These results also demonstrate that it is possible to control on demand the formation and shape of microfilaments, in particular, of electrospun fibres by using ultraviolet light.
Characterization and expression of AMP-forming Acetyl-CoA Synthetase from Dunaliella tertiolecta and its response to nitrogen starvation stress
Authors: Liang Ming-Hua , Qv Xiao-Ying , Jin Hong-Hao , Jiang Jian-Guo 
Published: March 2016

AbstractAMP-forming acetyl-CoA synthetase (ACS) catalyzes the formation of acetyl-CoA. Here, a cDNA of ACS from Dunaliella tertiolecta (DtACS) was isolated using RACEs. The full-length DtACS cDNA (GenBank: KT692941) is 2,464 bp with a putative ORF of 2,184 bp, which encodes 727 amino acids with a predicted molecular weight of 79.72 kDa. DtACS has a close relationship with Chlamydomonas reinhardtii and Volvox carteri f. nagariensis. ACSs existing in Bacteria, Archaea and Eukaryota share ten conserved motifs (A1–A10) and three signature motifs (I–III) of the acyl-adenylate/thioester forming enzyme superfamily. DtACS was expressed in E. coli BL21 as Trx-His-tagged fusion protein (~100 kDa) and the enzymatic activity was detected. The recombinant DtACS was purified by HisTrapTM HP affinity chromatography to obtain a specific activity of 52.873 U/mg with a yield of 56.26%, which approached the specific activity of ACS isolated from other eukaryotes. Kinetic analysis indicated that the Km of DtACS was 3.59 mM for potassium acetate and the purified DtACS exhibited a temperature optimum of 37 °C and a pH optimum of 8.0. In addition, the expression levels of DtACS were increased after nitrogen starvation cultivation, indicating that ACS activity may be related to the lipid accumulation under nitrogen deficient condition.
Boosting the power performance of multilayer graphene as lithium-ion battery anode via unconventional doping with in-situ formed Fe nanoparticles
Authors: Raccichini Rinaldo , Varzi Alberto , Chakravadhanula Venkata Sai Kiran , Kübel Christian , Passerini Stefano 
Published: March 2016

AbstractGraphene is extensively investigated and promoted as a viable replacement for graphite, the state-of-the-art material for lithium-ion battery (LIB) anodes, although no clear evidence is available about improvements in terms of cycling stability, delithiation voltage and volumetric capacity. Here we report the microwave-assisted synthesis of a novel graphene-based material in ionic liquid (i.e., carved multilayer graphene with nested Fe3O4 nanoparticles), together with its extensive characterization via several physical and chemical techniques. When such a composite material is used as LIB anode, the carved paths traced by the Fe3O4 nanoparticles, and the unconverted metallic iron formed in-situ upon the 1st lithiation, result in enhanced rate capability and, especially at high specific currents (i.e., 5 A g−1), remarkable cycling stability (99% of specific capacity retention after 180 cycles), low average delithiation voltage (0.244 V) and a substantially increased volumetric capacity with respect to commercial graphite (58.8 Ah L−1 vs. 9.6 Ah L−1).
NRP2 transcriptionally regulates its downstream effector WDFY1
Authors: Dutta Samikshan , Roy Sohini , Polavaram Navatha S , Baretton Gustavo B. , Muders Michael H. , Batra Surinder , Datta Kaustubh 
Published: March 2016

AbstractNeuropilins (NRPs) are cell surface glycoproteins that often act as co-receptors for plexins and VEGF family receptors. Neuropilin-2 (NRP2), a family member of NRPs, was shown to regulate autophagy and endocytic trafficking in cancer cells, a function distinctly different from its role as a co-receptor. WD Repeat and FYVE domain containing 1 (WDFY1)–protein acts downstream of NRP2 for this function. Our results indicated that NRP2 maintains an optimum concentration of WDFY1 by negatively regulating its expression. Since increased expression of WDFY1 reduces the endocytic activity, maintenance of WDFY1 level is crucial in metastatic cancer cells to sustain high endocytic activity, essential for promotion of oncogenic activation and cancer cell survival. Here, we have delineated the underlying molecular mechanism of WDFY1 synthesis by NRP2. Our results indicated that NRP2 inhibits WDFY1 transcription by preventing the nuclear localization of a transcription factor, Fetal ALZ50-reactive clone 1 (FAC1). Our finding is novel as transcriptional regulation of a gene by NRP2 axis has not been reported previously. Regulation of WDFY1 transcription by NRP2 axis is a critical event in maintaining metastatic phenotype in cancer cells. Thus, inhibiting NRP2 or hyper-activating WDFY1 can be an effective strategy to induce cell death in metastatic cancer.
Phosphorylated 4EBP1 is associated with tumor progression and poor prognosis in Xp11.2 translocation renal cell carcinoma
Authors: Qu Yuanyuan , Zhao Rui , Wang Hongkai , Chang Kun , Yang Xiaoqun , Zhou Xiaoyan , Dai Bo , Zhu Yao , Shi Guohai , Zhang Hailiang , Ye Dingwei 
Published: March 2016

AbstractTwo main signaling pathways, PI3K-AKT-mTOR and RAS-MAPK, are involved in transmitting the proliferative signals which play critical roles in human cancers. However, the functions of these pathways in Xp11.2 RCC remain undefined. This study aimed to explore the expression of mTOR and MAPK cascades in Xp11.2 RCC and to assess the prognostic significance of proteins evaluated. Immunohistochemistry was performed to evaluate the expression of 4EBP1, p-4EBP1, p-mTOR, p-S6K and p-MAPK in 36 adult Xp11.2 RCC patients who were confirmed by FISH assay. Cox regression models were used to evaluate the prognostic value of all covariates. Among 36 assessed patients, 14 (38.9%), 26 (72.2%), 16 (44.4%), 19 (52.8%), and 9 (25.0%) patients showed high expression of 4EBP1, p-4EBP1, p-mTOR, p-S6K, and p-MAPK, respectively. We noted that p-4EBP1 expression was significantly correlated with lymph node metastases (P = 0.027). Multivariate analysis showed that high p-4EBP1 expression was an independent adverse prognostic factor for both PFS (HR = 33.750, P = 0.017) and OS (HR = 56.111, P = 0.026). Our findings suggest that p-4EBP1 may serve as a funnel factor that converge the upstream proliferative oncogenic signals. Effective inhibition of the pathways responsible for 4E-BP1 phosphorylation might be a useful strategy to improve the outcome of Xp11.2 RCC patients.
Characterization and compression of dissipative-soliton-resonance pulses in fiber lasers
Authors: Li Daojing , Li Lei , Zhou Junyu , Zhao Luming , Tang Dingyuan , Shen Deyuan 
Published: March 2016

AbstractWe report numerical and experimental studies of dissipative-soliton-resonance (DSR) in a fiber laser with a nonlinear optical loop mirror. The DSR pulse presents temporally a flat-top profile and a clamped peak power. Its spectrum has a rectangle profile with characteristic steep edges. It shows a unique behavior as pulse energy increases: The rectangle part of the spectrum is unchanged while the newly emerging spectrum sits on the center part and forms a peak. Experimental observations match well with the numerical results. Moreover, the detailed evolution of the DSR pulse compression is both numerically and experimentally demonstrated for the first time. An experimentally obtained DSR pulse of 63 ps duration is compressed down to 760 fs, with low-intensity pedestals using a grating pair. Before being compressed to its narrowest width, the pulse firstly evolves into a cat-ear profile and the corresponding autocorrelation trace shows a crown shape, which distinguishes itself from properties of other solitons formed in fiber lasers.
Charge carrier coherence and Hall effect in organic semiconductors
Authors: Yi H. T. , Gartstein Y. N. , Podzorov V. 
Published: March 2016

AbstractHall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.
Retrieving transient conformational molecular structure information from inner-shell photoionization of laser-aligned molecules
Authors: Wang Xu , Le Anh-Thu , Yu Chao , Lucchese R. R. , Lin C. D. 
Published: March 2016

AbstractWe discuss a scheme to retrieve transient conformational molecular structure information using photoelectron angular distributions (PADs) that have averaged over partial alignments of isolated molecules. The photoelectron is pulled out from a localized inner-shell molecular orbital by an X-ray photon. We show that a transient change in the atomic positions from their equilibrium will lead to a sensitive change in the alignment-averaged PADs, which can be measured and used to retrieve the former. Exploiting the experimental convenience of changing the photon polarization direction, we show that it is advantageous to use PADs obtained from multiple photon polarization directions. A simple single-scattering model is proposed and benchmarked to describe the photoionization process and to do the retrieval using a multiple-parameter fitting method.
Electric-field-induced AFE-FE transitions and associated strain/preferred orientation in antiferroelectric PLZST
Authors: Lu Teng , Studer Andrew J. , Noren Lasse , Hu Wanbiao , Yu Dehong , McBride Bethany , Feng Yujun , Withers Ray L. , Chen Hua , Xu Zhuo , Liu Yun 
Published: March 2016

AbstractElectric-field-induced, antiferroelectric-ferroelectric (AFE-FE) phase transitions are common for AFE materials. To date, the strain and preferred orientation evolution as well as the role of the intermediate FE state during the successive AFE-FE-AFE phase transitions has not been clear. To this end, we have herein studied a typical AFE Pb0.97La0.02(Zr0.56Sn0.33Ti0.11)O3(PLZST) material usingin-situneutron diffraction. It is striking that the AFE-FE phase transition is not fully reversible: in the electric-field-induced FE state, the induced strain exhibits an elliptical distribution, which in turn leads to significant preferred orientation in the final AFE state after withdrawal of the applied electric-field. The ω-dependent neutron diffraction patterns show clear evidence of the induced strain distribution and associated preferred orientation arising from the AFE-FE phase transition. The current work also provides an explanation for several temperature and electric-field dependent dielectric anomalies as well as unrecovered strain change which appear in AFE materials after exposure to sufficiently high electric fields.
Proteomics of thyroid tumours provides new insights into their molecular composition and changes associated with malignancy
Authors: Martínez-Aguilar Juan , Clifton-Bligh Roderick , Molloy Mark P. 
Published: March 2016

AbstractAround 5% of the general population have palpable thyroid nodules. Although most thyroid tumours are benign, thyroid cancer represents the most common malignancy of the endocrine system, comprising mainly follicular and papillary thyroid carcinomas. Previous studies have shed some light on the molecular pathogenesis of thyroid cancer but there have not been any comprehensive mass spectrometry-based proteomic studies of large scale to reveal protein expression differences between thyroid tumours and the molecular alterations associated with tumour malignancy. We applied data-independent acquisition mass spectrometry which enabled quantitative expression analysis of over 1,600 proteins from 32 specimens to compare normal thyroid tissue with the three most common tumours of the thyroid gland: follicular adenoma, follicular carcinoma and papillary carcinoma. In follicular tumours, we found marked reduction of the tumour suppressor and therapeutic target extracellular protein decorin. We made the novel observation that TGFβ-induced protein ig-h3 (TGFBI) was found frequently overexpressed in follicular carcinoma compared with follicular adenoma. Proteomic pathway analysis showed changes in papillary carcinoma were associated with disruption of cell contacts (loss of E-cadherin), actin cytoskeleton dynamics and loss of differentiation markers, all hallmarks of an invasive phenotype.
Impaired ROS Scavenging System in Human Induced Pluripotent Stem Cells Generated from Patients with MERRF Syndrome
Authors: Chou Shih-Jie , Tseng Wei-Lien , Chen Chien-Tsun , Lai Yu-Fen , Chien Chian-Shiu , Chang Yuh-Lih , Lee Hsin-Chen , Wei Yau-Huei , Chiou Shih-Hwa 
Published: March 2016

AbstractMyoclonus epilepsy associated with ragged-red fibers (MERRF) is a mitochondrial disorder characterized by myoclonus epilepsy, generalized seizures, ataxia and myopathy. MERRF syndrome is primarily due to an A to G mutation at mtDNA 8344 that disrupts the mitochondrial gene for tRNA(Lys). However, the detailed mechanism by which this tRNA(Lys) mutation causes mitochondrial dysfunction in cardiomyocytes or neurons remains unclear. In this study, we generated human induced pluripotent stem cells (hiPSCs) that carry the A8344G genetic mutation from patients with MERRF syndrome. Compared with mutation-free isogenic hiPSCs, MERRF-specific hiPSCs (MERRF-hiPSCs) exhibited reduced oxygen consumption, elevated reactive oxygen species (ROS) production, reduced growth and fragmented mitochondrial morphology. We sought to investigate the induction ability and mitochondrial function of cardiomyocyte-like cells differentiated from MERRF-hiPSCs. Our data demonstrate that that cardiomyocyte-like cells (MERRF-CMs) or neural progenitor cells (MERRF-NPCs) differentiated from MERRF-iPSCs also exhibited increased ROS levels and altered antioxidant gene expression. Furthermore, MERRF-CMs or -NPCs contained fragmented mitochondria, as evidenced by MitoTracker Red staining and transmission electron microscopy. Taken together, these findings showed that MERRF-hiPSCs and MERRF-CM or –NPC harboring the A8344G genetic mutation displayed contained mitochondria with an abnormal ultrastructure, produced increased ROS levels and expressed upregulated antioxidant genes.
Hydrogenations and electric field induced magnetic behaviors in armchair silicene nanoribbons
Authors: Zhang Dan , Long Mengqiu , Xie Fang , Ouyang Jun , Xu Hui , Gao Yongli 
Published: March 2016

AbstractUsing the first-principles calculations, we investigate the geometric, electronic and magnetic properties of armchair silicene nanoribbons with different edge hydrogenations. Our results show that the interesting magnetic behaviors such as the bipolar magnetic semiconductor can be found. Moreover, the addition of the transverse electric field can modulate the bipolar magnetic semiconductor to half-metal or spin-splitting metal. And the spin-up electrons are localized at one edge, the spin-down holes localized at the opposite edge under the external electric field. These results may present a new avenue for band engineering of silicene nanoribbons and benefit the design of silicon-based nano-spin-devices in nanoelectronics.
Geometry- and Length Scale-Dependent Deformation and Recovery on Micro- and Nanopatterned Shape Memory Polymer Surfaces
Authors: Lee Wei Li , Low Hong Yee 
Published: March 2016

AbstractMicro- and nanoscale surface textures, when optimally designed, present a unique approach to improve surface functionalities. Coupling surface texture with shape memory polymers may generate reversibly tuneable surface properties. A shape memory polyetherurethane is used to prepare various surface textures including 2 μm- and 200 nm-gratings, 250 nm-pillars and 200 nm-holes. The mechanical deformation via stretching and recovery of the surface texture are investigated as a function of length scales and shapes. Results show the 200 nm-grating exhibiting more deformation than 2 μm-grating. Grating imparts anisotropic and surface area-to-volume effects, causing different degree of deformation between gratings and pillars under the same applied macroscopic strain. Full distribution of stress within the film causes the holes to deform more substantially than the pillars. In the recovery study, unlike a nearly complete recovery for the gratings after 10 transformation cycles, the high contribution of surface energy impedes the recovery of holes and pillars. The surface textures are shown to perform a switchable wetting function. This study provides insights into how geometric features of shape memory surface patterns can be designed to modulate the shape programming and recovery and how the control of reversibly deformable surface textures can be applied to transfer microdroplets.
Prefoldin and Pins synergistically regulate asymmetric division and suppress dedifferentiation
Authors: Zhang Yingjie , Rai Madhulika , Wang Cheng , Gonzalez Cayetano , Wang Hongyan 
Published: March 2016

AbstractPrefoldin is a molecular chaperone complex that regulates tubulin function in mitosis. Here, we show that Prefoldin depletion results in disruption of neuroblast polarity, leading to neuroblast overgrowth inDrosophilalarval brains. Interestingly, co-depletion of Prefoldin and Partner of Inscuteable (Pins) leads to the formation of gigantic brains with severe neuroblast overgrowth, despite that Pins depletion alone results in smaller brains with partially disrupted neuroblast polarity. We show that Prefoldin acts synergistically with Pins to regulate asymmetric division of both neuroblasts and Intermediate Neural Progenitors (INPs). Surprisingly, co-depletion of Prefoldin and Pins also induces dedifferentiation of INPs back into neuroblasts, while depletion either Prefoldin or Pins alone is insufficient to do so. Furthermore, knocking down eitherα-tubulinorβ-tubulininpins-mutant background results in INP dedifferentiation back into neuroblasts, leading to the formation of ectopic neuroblasts. Overexpression of α-tubulin suppresses neuroblast overgrowth observed inprefoldin pinsdouble mutant brains. Our data elucidate an unexpected function of Prefoldin and Pins in synergistically suppressing dedifferentiation of INPs back into neural stem cells.