bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nature and Evolution of Crust in Southern Lhasa, Tibet: Transformation From Microcontinent to Juvenile Terrane
Authors: Ma Lin , Kerr Andrew C. , Wang Qiang , Jiang Zi‐Qi , Tang Gong‐Jian , Yang Jin‐Hui , Xia Xiao‐Ping , Hu Wan‐Long , Yang Zong‐Yong , Sun Peng 
Published: June 2019

AbstractThe nature and pre‐Cenozoic evolution history of crust in southern Lhasa, which is crucial for our understanding of Indo‐Asian continental collision and Tibetan uplift during the Cenozoic, remains controversial due to a “missing” pre‐Mesozoic magmatic record. In this contribution, we report petrological and geochemical data for newly identified Paleozoic bimodal magmatism in the Zhengga area of southern Tibet. The magmatism comprises Late Devonian‐Early Carboniferous (366–353 Ma) amphibolite and two‐mica gneissic granite. The protoliths of the Zhengga amphibolite were gabbro and diorite with low SiO2 and high MgO, Cr, and Ni contents with high εNd(t) values of +3.3 to +8.0, variable and positive zircon εHf(t) of +0.9 to +11.2, and low zircon δ18O of 5.7 ± 0.2‰. These protoliths are proposed to have formed by decompression melting of asthenosphere during intracontinental back‐arc extension. In contrast, the granite has relatively high SiO2 and low MgO contents with much lower εNd(t) of −8.6 to −7.3, variable and negative zircon εHf(t) of −10.4 to −1.3, and high zircon δ18O of 9.4 ± 0.2‰ values and was most likely derived from an ancient metasedimentary source. This magma subsequently underwent recharge with minor amounts mafic magma followed by fractional crystallization of K‐feldspar in middle‐upper crust (~10–20 km) magma chambers. Using our new data, in combination with Nd‐Hf isotopes, we present the first comprehensive picture of crustal evolution in southern Lhasa. The southern Lhasa sub‐block is likely to have been a microcontinent that underwent extensive Phanerozoic crustal reworking and growth, rather than a Mesozoic‐Early Tertiary juvenile accretionary arc terrane.
Assessing the Chemistry and Bioavailability of Dissolved Organic Matter From Glaciers and Rock Glaciers
Authors: Fegel Timothy , Boot Claudia M. , Broeckling Corey D. , Baron Jill S. , Hall Ed K. 
Published: June 2019

AbstractAs glaciers thaw in response to warming, they release dissolved organic matter (DOM) to alpine lakes and streams. The United States contains an abundance of both alpine glaciers and rock glaciers. Differences in DOM composition and bioavailability between glacier types, like rock and ice glaciers, remain undefined. To assess differences in glacier and rock glacier DOM we evaluated bioavailability and molecular composition of DOM from four alpine catchments each with a glacier and a rock glacier at their headwaters. We assessed bioavailability of DOM by incubating each DOM source with a common microbial community and evaluated chemical characteristics of DOM before and after incubation using untargeted gas chromatography–mass spectrometry‐based metabolomics. Prior to incubations, ice glacier and rock glacier DOM had similar C:N ratios and chemical diversity, but differences in DOM composition. Incubations with a common microbial community showed that DOM from ice glacier meltwaters contained a higher proportion of bioavailable DOM and resulted in greater bacterial growth efficiency. After incubation, DOM composition from each source was statistically indistinguishable. This study provides an example of how MS‐based metabolomics can be used to assess effects of DOM composition on differences in bioavailability of DOM. Furthermore, it illustrates the importance of microbial metabolism in structuring composition of DOM. Even though rock glaciers had significantly less bioavailable DOM than ice glaciers, both glacial types still have potential to be important sources of bioavailable DOM to alpine headwaters over the coming decades.
Development of Late Jurassic‐Early Paleogene and Neogene‐Quaternary Rifts Within the Turkana Depression, East Africa From Satellite Gravity Data
Authors: Emishaw Luelseged , Abdelsalam Mohamed G. 
Published: June 2019

AbstractThe Turkana Depression (TD) is a NW trending topographic corridor within the East African Rift System between the Ethiopia‐Yemen plateau in the northeast and the East African plateau to the southwest. The Anza rift within the TD is a NW‐SE trending failed arm of a late Jurassic rift‐rift‐rift triple junction. This rift is correlated with the Sudan and South Sudan rifts. The Anza rift is intersected by the East African Rift System represented by the N‐S trending Turkana rifted zone. We image the lithospheric structure beneath the TD using satellite gravity data. We also use these data to model crustal density distribution beneath the Kino Sogo fault belt, part of the Turkana rifted zone. Our results show thinner crust (23–28 km) and lithosphere (140–150 km) beneath the TD. We interpret this as due to extension that resulted in the formation of the Kenya‐Sudan and South Sudan rifts. Our results also show that crustal depth between 0 and 4.8 km is dominated by N‐S density contrast anomalies and between 4.8 and 14.5 km by E‐W anomalies. We interpret the N‐S anomalies as due to the presence of Precambrian structure that might have facilitated strain localization during the initiation of the Kino Sogo fault belt. Differently, we interpret the E‐W anomalies as due to the presence E‐W trending faults that were formed in association with the development of the Anza rift and/or Turkana rifted zone and were later filled with Mesozoic and Cenozoic mafic dikes.
From Points to Patterns: Using Groundwater Time Series Clustering to Investigate Subsurface Hydrological Connectivity and Runoff Source Area Dynamics
Authors: Rinderer M. , van Meerveld H. J. , McGlynn B. L. 
Published: June 2019

AbstractGroundwater levels are typically measured at only a limited number of points in a catchment. Thus, upscaling these point measurements to the catchment scale is necessary to determine subsurface flow paths and runoff source areas. Here we present a data‐driven approach composed of time series clustering and topography‐based upscaling of shallow, perched groundwater dynamics using groundwater data from 51 monitoring sites in a 20‐ha prealpine headwater catchment in Switzerland. The agreement between the upscaled (modeled) and measured groundwater dynamics was strong for most of the 19‐month study period for the upslope and footslope locations but weaker at the beginning of events and for the midslope locations. However, these differences between measured and modeled groundwater levels did not significantly affect modeled groundwater activation, that is, the time when groundwater levels were within the more transmissive soil layers near the soil surface. The resulting groundwater activation maps represent the groundwater response across the catchment and highlight the dynamic expansion and contraction of the subsurface runoff source areas, particularly along the channel network. This is in agreement with the variable source area concept. However, there were also isolated active zones that did not get connected to the stream during rainfall events, highlighting the need to distinguish between variable active and variable stream‐connected runoff source areas. Our data‐driven approach to upscale point measurements of shallow groundwater levels appears useful for studying catchment‐scale variations in groundwater storage and connectivity and thus may help to better understand runoff generation in mountain catchments.
Roles of circular RNAs in immune regulation and autoimmune diseases
Authors: Zhou Zheng , Sun Bao , Huang Shiqiong , Zhao Lingling 
Published: June 2019

AbstractCircular RNAs (circRNAs), as a novel class of endogenously expressed non-coding RNAs (ncRNAs), have a high stability and often present tissue-specific expression and evolutionary conservation. Emerging evidence has suggested that circRNAs play an essential role in complex human pathologies. Notably, circRNAs, important gene modulators in the immune system, are strongly associated with the occurrence and development of autoimmune diseases. Here, we focus on the roles of circRNAs in immune cells and immune regulation, highlighting their potential as biomarkers and biological functions in autoimmune diseases, such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), multiple sclerosis (MS), primary biliary cholangitis (PBC), and psoriasis, aiming at providing new insights into the diagnosis and therapy of these diseases.
A shape-memory and spiral light-emitting device for precise multisite stimulation of nerve bundles
Authors: Zheng Hao , Zhang Zhitao , Jiang Su , Yan Biao , Shi Xiang , Xie Yuanting , Huang Xu , Yu Zeyang , Liu Huizhu , Weng Shijun , Nurmikko Arto , Zhang Yuqiu , Peng Huisheng , Xu Wendong , Zhang Jiayi 
Published: June 2019

AbstractWe previously demonstrated that for long-term spastic limb paralysis, transferring the seventh cervical nerve (C7) from the nonparalyzed side to the paralyzed side results in increase of 17.7 in Fugl-Meyer score. One strategy for further improvement in voluntary arm movement is selective activation of five target muscles innervated by C7 during recovery process. In this study, we develop an implantable multisite optogenetic stimulation device (MOSD) based on shape-memory polymer. Two-site stimulation of sciatic nerve bundles by MOSD induces precise extension or flexion movements of the ankle joint, while eight-site stimulation of C7 nerve bundles induce selective limb movement. Long-term implant of MOSD to mice with severed and anastomosed C7 nerve is proven to be both safe and effective. Our work opens up the possibility for multisite nerve bundle stimulation to induce highly-selective activations of limb muscles, which could inspire further applications in neurosurgery and neuroscience research.
Evidence for singular-phonon-induced nematic superconductivity in a topological superconductor candidate Sr0.1Bi2Se3
Authors: Wang Jinghui , Ran Kejing , Li Shichao , Ma Zhen , Bao Song , Cai Zhengwei , Zhang Youtian , Nakajima Kenji , Ohira-Kawamura Seiko , Čermák P. , Schneidewind A. , Savrasov Sergey Y. , Wan Xiangang , Wen Jinsheng 
Published: June 2019

AbstractSuperconductivity mediated by phonons is typically conventional, exhibiting a momentum-independent s-wave pairing function, due to the isotropic interactions between electrons and phonons along different crystalline directions. Here, by performing inelastic neutron scattering measurements on a superconducting single crystal of Sr0.1Bi2Se3, a prime candidate for realizing topological superconductivity by doping the topological insulator Bi2Se3, we find that there exist highly anisotropic phonons, with the linewidths of the acoustic phonons increasing substantially at long wavelengths, but only for those along the [001] direction. This observation indicates a large and singular electron-phonon coupling at small momenta, which we propose to give rise to the exotic p-wave nematic superconducting pairing in the MxBi2Se3 (M = Cu, Sr, Nb) superconductor family. Therefore, we show these superconductors to be example systems where electron-phonon interaction can induce more exotic superconducting pairing than the s-wave, consistent with the topological superconductivity.
Image Segmentation Based on Relative Motion and Relative Disparity Cues in Topographically Organized Areas of Human Visual Cortex
Authors: Kohler Peter J. , Cottereau Benoit R. , Norcia Anthony M. 
Published: June 2019

AbstractThe borders between objects and their backgrounds create discontinuities in image feature maps that can be used to recover object shape. Here we used functional magnetic resonance imaging to identify cortical areas that encode two of the most important image segmentation cues: relative motion and relative disparity. Relative motion and disparity cues were isolated by defining a central 2-degree disk using random-dot kinematograms and stereograms, respectively. For motion, the disk elicited retinotopically organized activations starting in V1 and extending through V2 and V3. In the surrounding region, we observed phase-inverted activations indicative of suppression, extending out to at least 6 degrees of retinal eccentricity. For disparity, disk activations were only found in V3, while suppression was observed in all early visual areas. Outside of early visual cortex, several areas were sensitive to both types of cues, most notably LO1, LO2 and V3B, making them additional candidate areas for motion- and disparity-cue combination. Adding an orthogonal task at fixation did not diminish these effects, and in fact led to small but measurable disk activations in V1 and V2 for disparity. The overall pattern of extra-striate activations is consistent with recent three-stream models of cortical organization.
Tremorgenic effects and functional metabolomics analysis of lolitrem B and its biosynthetic intermediates
Authors: Reddy Priyanka , Rochfort Simone , Read Elizabeth , Deseo Myrna , Jaehne Emily , Van Den Buuse Maarten , Guthridge Kathryn , Combs Martin , Spangenberg German , Quinn Jane 
Published: June 2019

AbstractThe neuroactive mycotoxin lolitrem B causes a neurological syndrome in grazing livestock resulting in hyperexcitability, muscle tremors, ataxia and, in severe cases, clonic seizures and death. To define the effects of the major toxin lolitrem B in the brain, a functional metabolomic study was undertaken in which motor coordination and tremor were quantified and metabolomic profiling undertaken to determine relative abundance of both toxin and key neurotransmitters in various brain regions in male mice. Marked differences were observed in the duration of tremor and coordination between lolitrem B pathway members, with some showing protracted effects and others none at all. Lolitrem B was identified in liver, kidney, cerebral cortex and thalamus but not in brainstem or cerebellum which were hypothesised previously to be the primary site of action. Metabolomic profiling showed significant variation in specific neurotransmitter and amino acid profiles over time. This study demonstrates accumulation of lolitrem B in the brain, with non-detectable levels of toxin in the brainstem and cerebellum, inducing alterations in metabolites such as tyrosine, suggesting a dynamic catecholaminergic response over time. Temporal characterisation of key pathways in the pathophysiological response of lolitrem B in the brain were also identified.
Skeletal descriptions of shape provide unique perceptual information for object recognition
Authors: Ayzenberg Vladislav , Lourenco Stella F. 
Published: June 2019

AbstractWith seemingly little effort, humans can both identify an object across large changes in orientation and extend category membership to novel exemplars. Although researchers argue that object shape is crucial in these cases, there are open questions as to how shape is represented for object recognition. Here we tested whether the human visual system incorporates a three-dimensional skeletal descriptor of shape to determine an object’s identity. Skeletal models not only provide a compact description of an object’s global shape structure, but also provide a quantitative metric by which to compare the visual similarity between shapes. Our results showed that a model of skeletal similarity explained the greatest amount of variance in participants’ object dissimilarity judgments when compared with other computational models of visual similarity (Experiment 1). Moreover, parametric changes to an object’s skeleton led to proportional changes in perceived similarity, even when controlling for another model of structure (Experiment 2). Importantly, participants preferentially categorized objects by their skeletons across changes to local shape contours and non-accidental properties (Experiment 3). Our findings highlight the importance of skeletal structure in vision, not only as a shape descriptor, but also as a diagnostic cue of object identity.
Correlation of ultra-high field MRI with histopathology for evaluation of rectal cancer heterogeneity
Authors: Pham Trang T. , Stait-Gardner Timothy , Lee Cheok Soon , Barton Michael , Graham Petra L. , Liney Gary , Wong Karen , Price William S. 
Published: June 2019

AbstractCurrent clinical MRI techniques in rectal cancer have limited ability to examine cancer stroma. The differentiation of tumour from desmoplasia or fibrous tissue remains a challenge. Standard MRI cannot differentiate stage T1 from T2 (invasion of muscularis propria) tumours. Diffusion tensor imaging (DTI) can probe tissue structure and organisation (anisotropy). The purpose of this study was to examine DTI-MRI derived imaging markers of rectal cancer stromal heterogeneity and tumour extent ex vivo. DTI-MRI at ultra-high magnetic field (11.7 tesla) was used to examine the stromal microstructure of malignant and normal rectal tissue ex vivo, and the findings were correlated with histopathology. Images obtained from DTI-MRI (A0, apparent diffusion coefficient and fractional anisotropy (FA)) were used to probe rectal cancer stromal heterogeneity. FA provided the best discrimination between cancer and desmoplasia, fibrous tissue and muscularis propria. Cancer had relatively isotropic diffusion (mean FA 0.14), whereas desmoplasia (FA 0.31) and fibrous tissue (FA 0.34) had anisotropic diffusion with significantly higher FA than cancer (p < 0.001). Tumour was distinguished from muscularis propria (FA 0.61) which was highly anisotropic with higher FA than cancer (p < 0.001). This study showed that DTI-MRI can assist in more accurately defining tumour extent in rectal cancer.
Establishment of mesophilic-like catalytic properties in a thermophilic enzyme without affecting its thermal stability
Authors: Akanuma Satoshi , Bessho Mizumo , Kimura Hikono , Furukawa Ryutaro , Yokobori Shin-ichi , Yamagishi Akihiko 
Published: June 2019

AbstractThermophilic enzymes are generally more thermally stable but are less active at moderate temperatures than are their mesophilic counterparts. Thermophilic enzymes with improved low-temperature activity that retain their high stability would serve as useful tools for industrial processes especially when robust biocatalysts are required. Here we show an effective way to explore amino acid substitutions that enhance the low-temperature catalytic activity of a thermophilic enzyme, based on a pairwise sequence comparison of thermophilic/mesophilic enzymes. One or a combination of amino acid(s) in 3-isopropylmalate dehydrogenase from the extreme thermophile Thermus thermophilus was/were substituted by a residue(s) found in the Escherichia coli enzyme at the same position(s). The best mutant, which contained three amino acid substitutions, showed a 17-fold higher specific activity at 25 °C compared to the original wild-type enzyme while retaining high thermal stability. The kinetic and thermodynamic parameters of the mutant showed similar patterns along the reaction coordinate to those of the mesophilic enzyme. We also analyzed the residues at the substitution sites from a structural and phylogenetic point of view.
Combining Phase Advancement and Period Correction Explains Rushing during Joint Rhythmic Activities
Authors: Wolf Thomas , Vesper Cordula , Sebanz Natalie , Keller Peter E. , Knoblich Günther 
Published: June 2019

AbstractWhen people engage in rhythmic joint actions, from simple clapping games to elaborate joint music making, they tend to increase their tempo unconsciously. Despite the rich literature on rhythmic performance in humans, the mechanisms underlying joint rushing are still unknown. We propose that joint rushing arises from the concurrent activity of two separate mechanisms. The phase advance mechanism was first proposed in research on synchronously flashing fireflies and chorusing insects. When this mechanism is combined with a human-specific period correction mechanism, the shortened periods of individual intervals are translated into a tempo increase. In three experiments, we investigated whether joint rushing can be reliably observed in a joint synchronization-continuation drumming task. Furthermore, we asked whether perceptual similarities produced by the actions of different individuals modulate the joint rushing effect. The results showed that joint rushing is a robust phenomenon occurring in groups of different sizes. Joint rushing was more pronounced when the action effects produced by different individuals were perceptually similar, supporting the assumption that a phase advance mechanism contributed to rushing. Further control conditions ruled out the alternative hypothesis that rushing during rhythmic interactions can be explained by social facilitation or action mirroring effects.
A Novel Technique Enables Quantifying the Molecular Interaction of Solvents with Biological Tissues
Authors: Yadav Sakshi , Gulec Semih , Tadmor Rafael , Lian Ian 
Published: June 2019

AbstractThe pharmaceutical industry uses various solvents to increase drug penetrability to tissues. The solvent’s choice affects the efficacy of a drug. In this paper, we provide an unprecedented means of relating a solvent to a tissue quantitatively. We show that the solvents induce reorientation of the tissue surface molecules in a way that favors interaction and, therefore, penetrability of a solvent to a tissue. We provide, for the first time, a number for this tendency through a new physical property termed Interfacial Modulus (Gs). Gs, which so far was only predicted theoretically, is inversely proportional to such interactions. As model systems, we use HeLa and HaCaT tissue cultures with water and with an aqueous DMSO solution. The measurements are done using Centrifugal Adhesion Balance (CAB) when set to effective zero gravity. As expected, the addition of DMSO to water reduces Gs. This reduction in Gs is usually higher for HaCaT than for HeLa cells, which agrees with the common usage of DMSO in dermal medicine. We also varied the rigidities of the tissues. The tissue rigidity is not expected to relate to Gs, and indeed our results didn’t show a correlation between these two physical properties.
Investigation into using resonant frequency measurements to predict the mechanical properties of Ti-6Al-4V manufactured by selective laser melting
Authors: Todd Mark A. , Hunt James , Todd Iain 
Published: June 2019

AbstractThere is a need to qualify additively manufactured parts that are used in highly regulated industries such as aerospace and nuclear power. This paper investigates the use of resonant ultrasound measurements to predict the mechanical properties of Ti-6Al-4V manufactured by selective laser melting using a Renishaw AM 250. It is first demonstrated whyR2should not be used to assess the predictive capability of a model, before introducing a method for calculating predictedR2, which is then used to assess the models. It is found that a linear model with the resonant frequency peaks as predictors cannot be used to predict elongation at failure or reduction in area. However, linear models did demonstrate better predictive capabilities for Young’s modulus, yield strength, and especially ultimate tensile strength.