bluuebunny/crossref_metadata_2025_split huggingface dataset:
Raised Rims Around Titan's Sharp‐Edged Depressions
Authors: Birch S. P. D. , Hayes A. G. , Poggiali V. , Hofgartner J. D. , Lunine J. I. , Malaska M. J. , Wall S. , Lopes R. M. C. , White O. 
Published: May 2018

AbstractWe perform a systematic survey of Titan's sharp‐edged depressions (SEDs) using a combination of Cassini synthetic aperture radar images and delay‐Doppler processed altimetry. We identify a characteristic bright‐dark pattern around 172 SEDs that correlates with elevated features only resolved with the highest resolution topographic data. We find that ∼75% of Titan's SEDs have elevated (∼100 m) rim features, with a preference toward larger SEDs. The differences in the distribution of SED rim presence between the north and south are slight, but the data weakly suggest that northern SEDs may be more likely to have a rim. The pattern we identify in synthetic aperture radar images is similar to quasi‐specular increases in backscatter seen on Titan's dunes. We show that this bright‐dark pattern occurs due to elevated local slopes oriented perpendicular to the radar. In general, rims occur on most of Titan's SEDs, an observation that will aid in developing and testing SED formation models.
Trace Metal Enrichment Driven by Phosphate Functional Group Binding Selectivity
Authors: Zhang Ting , Fiamingo Michelle , Allen Heather C. 
Published: May 2018

AbstractTrace metals have been found to be selectively enriched in the sea surface microlayer (SSML) due to association with organics, but the underlying cause of this selectivity has not been as well studied. Therefore, a systematic cation affinity study on surfactant lipids containing various functional headgroups (‐OH, ‐H2PO4, ‐COOH, ‐N(CH3)2) was conducted at pH 3 to further explain cation enrichment selectivity using Brewster angle microscopy, surface tension salt titration, and infrared‐reflection absorption spectroscopy (IRRAS). At pH 3, the headgroups chosen are neutral, and therefore the variability of surface charge on binding is eliminated. The phosphate ester headgroup was observed to exhibit the strongest trace metal binding, followed by the carboxylic acid headgroup. Hydroxy and dimethylamine headgroups did not exhibit significant trace metal binding. By applying the Langmuir‐Szyszkowski model to the surface tension data, the cation surface binding affinities for phosphatidic acid were determined, with Al3+ > Fe3+ > Zn2+> Mg2+ > Ni2+ > Mn2+∼ Ca2+, an order not predicted from bulk properties such as solid formation constants of metal‐phosphonates. Thus cation binding to surface active organic molecules with phosphate ester headgroups is indicated to be a significant source of trace metal enrichment within the SSML.
Summer Intraseasonal Surface Heat Flux‐Sea Surface Temperature Relationship Over Northern Tropical Indo‐Western Pacific in Climate Models
Authors: Wu Renguang , You Ting 
Published: May 2018

AbstractThe present study documents the relationship between intraseasonal net surface heat flux (NHF, positive for downward flux) and sea surface temperature (SST) variations over the North Indian Ocean and tropical western North Pacific during May through September in climate models. A distinct NHF‐SST relationship is identified in the NCC.NorESM1‐M model. NHF has a weak correlation with the SST tendency but a large negative correlation with SST in the NCC.NorESM1‐M model, whereas NHF has a large positive correlation with the SST tendency and a weak correlation with SST in observations and some other climate models. The sea‐air humidity difference has a dominant contribution to latent heat flux variations in relation to a bias toward larger mean wind speed in the NCC.NorESM1‐M model. In contrast, surface wind speed overcomes the sea‐air humidity difference in contributing to latent heat flux variations due to a bias toward larger mean sea‐air humidity difference in the INM.inmcm4 model. Detailed analysis reveals different processes in intraseasonal SST variations in the South China Sea between the INM.inmcm4 and NCC.NorESM1‐M models. In the INM.inmcm4 model, atmosphere‐induced shortwave radiation and latent heat flux have a main contribution to the SST change. In the NCC.NorESM1‐M model, the SST change is mainly due to oceanic processes. The ocean‐induced positive SST anomalies increase evaporation and surface air humidity. This destabilizes the atmospheric boundary layer in favor of convection and reduced downward shortwave radiation. NHF has a damping effect on the SST change.
Microspectroscopic and Petrographic Comparison of Experimentally Shocked Albite, Andesine, and Bytownite
Authors: Jaret Steven J. , Johnson Jeffrey R. , Sims Melissa , DiFrancesco Nicholas , Glotch Timothy D. 
Published: May 2018

AbstractPlagioclase feldspars are common on the surfaces of planetary objects in the solar system such as the Moon and Mars, and in meteorites. Understanding their response to shock deformation is important for interpretations of data from remote sensing, returned samples, and naturally shocked samples from impact craters. We used optical petrography, micro‐Raman, and micro–Fourier transform infrared spectroscopy to systematically document vibrational spectral differences related to structural changes in experimentally shocked (0–56 GPa) albite‐, andesine‐, and bytownite‐rich rocks as a function of pressure and composition. Across all techniques, the specific composition of feldspars was confirmed to affect shock deformation, where more Ca‐rich feldspars transform to an amorphous phase at lower shock conditions than more Na‐rich feldspars. Onset of amorphization occurs at ~50 GPa for albite, between 28 and 30 GPa for andesine, and between 25 and 27 GPa for bytownite. Complete amorphization occurred at pressures greater than ~55 GPa for albite, ~47 GPa for andesine, and ~38 GPa for bytownite. Petrographically, these experimentally shocked samples do not exhibit the planar microstructures common in naturally shocked plagioclase, despite showing the expected trends of internal disordering and deformation as seen in the micro‐Raman and infrared spectra. Average spectra of hyperspectral images of these samples mimic macroscale measurements acquired previously. However, we see micro‐scale heterogeneity in the shock response, resulting from variations in either composition, crystal orientation, or the inherent heterogeneity of the shock wave topology. This is an important factor to consider when deducing shock pressures in naturally shocked samples.
Numerical Convergence of Shallow Convection Cloud Field Simulations: Comparison Between Double‐Moment Eulerian and Particle‐Based Lagrangian Microphysics Coupled to the Same Dynamical Core
Authors: Sato Yousuke , Shima Shin‐ichiro , Tomita Hirofumi 
Published: May 2018

AbstractThe sensitivity of simulated nonprecipitating cumulus clouds to grid length was investigated using a large‐eddy simulation model coupled to a particle‐based Lagrangian cloud microphysical model (LCM) and an Eulerian cloud microphysical model (ECM). For the sensitivity experiment, the horizontal/vertical grid length was decreased from 100/80 m to 6.25/5 m. The results of the sensitivity experiment indicated a similar dependency of cloud cover (CC) on the grid length in the LCM and ECM, which is critical for the radiative properties of clouds. CC increased with a shorter grid length, and numerically converged with a horizontal/vertical grid length of 12.5/10 m, although the three‐dimensional cloud field and turbulence properties in the cloud layer did not numerically converge and the cloud fields simulated by the LCM and ECM differed. The dependency of CC on grid length originated from the dependency of the turbulence structure in the subcloud layer. Roll convection was clearly simulated in the subcloud layer using a short grid length, but it was gradually obscured with increasing grid length. With a long grid length, the shear production term of turbulent kinetic energy near the surface, which is critical for dominating roll convection, was not simulated because of insufficient vertical layers near the surface. On the other hand, with a short grid length, the number of layers close to the surface was sufficient to reproduce the shear production term, and roll convection was clearly reproduced.
Active Bending‐Moment Faulting: Geomorphic Expression, Controlling Conditions, Accommodation of Fold Deformation
Authors: Li Tao , Chen Jie , Thompson Jobe Jessica A. , Burbank Douglas W. , Cheng Xiaogan , Xu Jianhong , Li Zhigang , Zheng Wenjun , Zhang Peizhen 
Published: May 2018

AbstractBending‐moment faults and flexural‐slip faults (FSFs), as two basic fault styles due to bending‐related tangential longitudinal strain, extensively and prominently crop out as surface scarps in the Pamir‐western Kunlun and southern Tian Shan regions, northwestern China. Characteristic geomorphic expression, favorable formation conditions, and the role in folding accommodation of active FSFs have been systematically summarized in our recent studies. Here we investigate similar properties for well‐developed bending‐moment normal fault (BMnF) scarps at four sites. Our study concludes the following: (i) BMnF scarps are relatively sinuous compared to FSF scarps and probably trend obliquely to the fold hinge. A group of BMnF scarps can delineate a single asymmetric graben or create grabens alternating with horsts. (ii) BMnF scarps primarily overlie poorly‐layered conglomerates. The fold's interlimb angle can range from ~160° to <40°, and the folding kinematics can vary from active‐hinge migration to fixed‐hinge rotation. (iii) The fault‐zone width, fault spacing, and efficiency in folding accommodation significantly decrease with (a) thinner conglomerate beds, (b) a smaller interlimb angle, and (c) the transition of the hinge from migrated to fixed. (iv) Different bed lithologies and fold geometries beneath the surface account for the predominance of BMnF scarps on the western Kunlun piedmont and FSF scarps in the Pamir‐Tian Shan convergent zone. (v) Presence of BMnF scarps on the western Kunlun piedmont indicates that ~4 km of fault slip is transferred northward along a detachment at the base of the Cenozoic and is ultimately absorbed by the Mazatagh Thrust in the Tarim Basin.
Metabolic patterns in insulin-sensitive male hypogonadism
Authors: Fanelli Giuseppina , Gevi Federica , Belardo Antonio , Zolla Lello 
Published: May 2018

AbstractMale hypogonadism is a disorder characterised by low levels of the hormone testosterone. At beginning subjects with low levels of testosterone do not show insulin resistance (insulin-sensitive patients), which develops over time (insulin-resistance patients). To analyse the metabolic alterations mainly related to decreased testosterone, we performed metabolomics investigations on the plasma of males with hypogonadism who showed normal insulin levels. Plasma from patients with low testosterone (<8 nmol/l) and homeostatic model assessment for insulin-resistance-index (HOMAi) < 2.5, as well as matched controls, was analysed by UHPLC and mass spectrometry. Then metabolites were then subjected to multivariate statistical analysis and grouped by metabolic pathways. Glycolysis was not altered, as expected for the presence of insulin activity, but imbalances in several other pathways were found, such as the pentose phosphate pathway (PPP), glycerol shuttle, malate shuttle, Krebs cycle (TCA) and lipid metabolism. The PPP was significantly upregulated. Moreover, while the first steps of the Krebs cycle were downregulated, 2-oxoglutarate was replenished via glutaminolysis. Since glutaminolysis leads to an activation of the malate aspartate cycle, greater amounts of NADH and ATP with respect to the control were recorded. The activation of the glycerol shuttle was also recorded, with consequent lower triglyceride production and downregulation of beta-oxidation. This explained the moderately increased dyslipidaemia, as well as the mild increase in body mass index (BMI) observed in insulin-sensitive hypogonadism. Finally, a significant decrease in carnosine was recorded, explaining the muscle weakness commonly observed.
MiR-142-3p is downregulated in aggressive p53 mutant mouse models of pancreatic ductal adenocarcinoma by hypermethylation of its locus
Authors: Godfrey Jack D. , Morton Jennifer P. , Wilczynska Ania , Sansom Owen J. , Bushell Martin D. 
Published: May 2018

AbstractPancreatic ductal adenocarcinoma (PDAC) is an extremely aggressive disease with poor prognostic implications. This is partly due to a large proportion of PDACs carrying mutations in TP53, which impart gain-of-function characteristics that promote metastasis. There is evidence that microRNAs (miRNAs) may play a role in both gain-of-function TP53 mutations and metastasis, but this has not been fully explored in PDAC. Here we set out to identify miRNAs which are specifically dysregulated in metastatic PDAC. To achieve this, we utilised established mouse models of PDAC to profile miRNA expression in primary tumours expressing the metastasis-inducing mutant p53R172H and compared these to two control models carrying mutations, which promote tumour progression but do not induce metastasis. We show that a subset of miRNAs are dysregulated in mouse PDAC tumour tissues expressing mutant p53R172H, primary cell lines derived from mice with the same mutations and in TP53 null cells with ectopic expression of the orthologous human mutation, p53R175H. Specifically, miR-142-3p is downregulated in all of these experimental models. We found that DNA methyltransferase 1 (Dnmt1) is upregulated in tumour tissue and cell lines, which express p53R172H. Inhibition or depletion of Dnmt1 restores miR-142-3p expression. Overexpression of miR-142-3p attenuates the invasive capacity of p53R172H-expressing tumour cells. MiR-142-3p dysregulation is known to be associated with cancer progression, metastasis and the miRNA is downregulated in patients with PDAC. Here we link TP53 gain-of-function mutations to Dnmt1 expression and in turn miR-142-3p expression. Additionally, we show a correlation between expression of these genes and patient survival, suggesting that they may have potential to be therapeutic targets.
The kinase receptor-interacting protein 1 is required for inflammasome activation induced by endoplasmic reticulum stress
Authors: Tao Liang , Lin Hongfa , Wen Jingjing , Sun Qi , Gao Yan , Xu Xi , Wang Junsong , Zhang Jianfa , Weng Dan 
Published: May 2018

AbstractEndoplasmic reticulum (ER) stress contributes to the development and progression of many chronic inflammatory diseases, including type 2 diabetes, obesity, atherosclerosis, neurodegenerative diseases, and cancer. ER stress has been reported to induce inflammasome activation and release of mature IL-1β, which contributes to many inflammatory diseases. The molecular mechanisms that activate the inflammasome during ER stress are still poorly understood. Here we report that the kinase receptor-interacting protein 1 (RIP1) plays an important role in ER stress-induced activation of inflammasome. Inhibition of RIP1 kinase activity by Necrostatin-1 or siRNA-mediated RIP1 knockdown significantly reduced ER stress-induced caspase-1 cleavage and IL-1β secretion in both bone marrow-derived macrophages (BMDMs) and J774A.1 macrophages. We speculate that the mitochondria fission factor dynamin-related protein 1 (DRP1) and reactive oxygen species (ROS) might function as the effectors downstream of RIP1 to mediate inflammasome activation. Our study reveals a critical role for RIP1 in regulating ER stress-induced inflammation responses, and proposes RIP1 as a potential pharmaceutical target to treat diseases resulting from unresolved ER stress-related inflammation.
miR-550a-3-5p acts as a tumor suppressor and reverses BRAF inhibitor resistance through the direct targeting of YAP
Authors: Choe Min Ho , Yoon Yina , Kim Joon , Hwang Sang-Gu , Han Young-Hoon , Kim Jae-Sung 
Published: May 2018

AbstractAlthough evidence has emerged to suggest that YAP overexpression is a crucial factor for tumor progression and resistance to targeted drugs in multiple cancers, the miRNA-mediated YAP regulation is still unclear. Here we show that the novel miR-550a-3-5p acts as a tumor suppressor and reverses BRAF inhibitor resistance through the direct targeting of YAP. Our data showed that the miR-550a-3-5p suppressed cell proliferation, metastasis, and tumor sphere formation through the direct inhibition of YAP and its oncogenic pathway in various cancer cell types. In addition, we showed that the YAP signature was associated with poor survival of colon cancer and identified an inverse correlation between miR-550a-3-5p and YAP in colon cancer tissues. Interestingly, this inverse correlation was regulated in a density-dependent manner. Furthermore, high levels of miR-550a-3-5p were associated with a good prognosis of esophageal cancer, which was suggestive of the clinical relevance of miR-550a-3-5p-mediated YAP regulation in multiple cancers. Importantly, we demonstrated that miR-550a-3-5p treatment sensitized vemurafenib-resistant colon and melanoma cells through YAP inhibition with reduced AKT activity. Moreover, the tumor-suppressive activity of miR-550a-3-5p and its sensitization effect for vemurafenib resistance were also observed in tumor xenograft models. Collectively, our data suggest that miR-550a-3-5p acts as a tumor suppressor through the targeting of oncogenic YAP and may be a new therapeutic tool for YAP-mediated BRAF inhibitor resistance in BRAF-mutant cancer cells.
Double quantum criticality in superconducting tin arrays-graphene hybrid
Authors: Sun Yinbo , Xiao Hong , Zhang Miao , Xue Zhongying , Mei Yongfeng , Xie Xiaoming , Hu Tao , Di Zengfeng , Wang Xi 
Published: May 2018

AbstractTwo magnetic-field-induced quantum critical behaviors were recently discovered in two dimensional electron gas (2DEG) at LaTiO3/SrTiO3 interface and interpreted by disordered superconducting puddles coupled through 2DEG. In this scenario, the 2DEG is proposed to undergo a spontaneous phase separation and breaks up into locally superconducting puddles in a metallic matrix. However, as the inhomogeneous superconducting 2DEG is only illative, this proposal still lacks the direct experimental demonstration. Here, we artificially construct superconducting puddles-2DEG hybrid system by depositing tin nanoislands array on single crystalline monolayer graphene, where the two quantum critical behaviors are reproduced. Through the finite-size scaling analysis on magnetoresistivity, we show that the two quantum critical behaviors result from the intra-island and inter-island phase coherence, respectively, which are further illustrated by the phase diagram. This work provides a platform to study superconducting quantum phase transitions in a 2D system and helps to integrate superconducting devices into semiconductor technology.
Live cyanobacteria produce photocurrent and hydrogen using both the respiratory and photosynthetic systems
Authors: Saper Gadiel , Kallmann Dan , Conzuelo Felipe , Zhao Fangyuan , Tóth Tünde N. , Liveanu Varda , Meir Sagit , Szymanski Jedrzej , Aharoni Asaph , Schuhmann Wolfgang , Rothschild Avner , Schuster Gadi , Adir Noam 
Published: May 2018

AbstractOxygenic photosynthetic organisms perform solar energy conversion of water and CO2 to O2 and sugar at a broad range of wavelengths and light intensities. These cells also metabolize sugars using a respiratory system that functionally overlaps the photosynthetic apparatus. In this study, we describe the harvesting of photocurrent used for hydrogen production from live cyanobacteria. A non-harmful gentle physical treatment of the cyanobacterial cells enables light-driven electron transfer by an endogenous mediator to a graphite electrode in a bio-photoelectrochemical cell, without the addition of sacrificial electron donors or acceptors. We show that the photocurrent is derived from photosystem I and that the electrons originate from carbohydrates digested by the respiratory system. Finally, the current is utilized for hydrogen evolution on the cathode at a bias of 0.65 V. Taken together, we present a bio-photoelectrochemical system where live cyanobacteria produce stable photocurrent that can generate hydrogen.
Cotransporter-mediated water transport underlying cerebrospinal fluid formation
Authors: Steffensen Annette B. , Oernbo Eva K. , Stoica Anca , Gerkau Niklas J. , Barbuskaite Dagne , Tritsaris Katerina , Rose Christine R. , MacAulay Nanna 
Published: May 2018

AbstractCerebrospinal fluid (CSF) production occurs at a rate of 500 ml per day in the adult human. Conventional osmotic forces do not suffice to support such production rate and the molecular mechanisms underlying this fluid production remain elusive. Using ex vivo choroid plexus live imaging and isotope flux in combination with in vivo CSF production determination in mice, we identify a key component in the CSF production machinery. The Na+/K+/2Cl− cotransporter (NKCC1) expressed in the luminal membrane of choroid plexus contributes approximately half of the CSF production, via its unusual outward transport direction and its unique ability to directly couple water transport to ion translocation. We thereby establish the concept of cotransport of water as a missing link in the search for molecular pathways sustaining CSF production and redefine the current model of this pivotal physiological process. Our results provide a rational pharmacological target for pathologies involving disturbed brain fluid dynamics.
Facilitators and barriers to physical activity following pulmonary rehabilitation in COPD: a systematic review of qualitative studies
Authors: Robinson Hayley , Williams Veronika , Curtis Ffion , Bridle Christopher , Jones Arwel W. 
Published: May 2018

AbstractPulmonary rehabilitation has short-term benefits on dyspnea, exercise capacity and quality of life in COPD, but evidence suggests these do not always translate to increased daily physical activity on a patient level. This is attributed to a limited understanding of the determinants of physical activity maintenance following pulmonary rehabilitation. This systematic review of qualitative research was conducted to understand COPD patients’ perceived facilitators and barriers to physical activity following pulmonary rehabilitation. Electronic databases of published data, non-published data, and trial registers were searched to identify qualitative studies (interviews, focus groups) reporting the facilitators and barriers to physical activity following pulmonary rehabilitation for people with COPD. Thematic synthesis of qualitative data was adopted involving line-by-line coding of the findings of the included studies, development of descriptive themes, and generation of analytical themes. Fourteen studies including 167 COPD patients met the inclusion criteria. Seven sub-themes were identified as influential to physical activity following pulmonary rehabilitation. These included: intentions, self-efficacy, feedback of capabilities and improvements, relationship with health care professionals, peer interaction, opportunities following pulmonary rehabilitation and routine. These encapsulated the facilitators and barriers to physical activity following pulmonary rehabilitation and were identified as sub-themes within the three analytical themes, which were beliefs, social support, and the environment. The findings highlight the challenge of promoting physical activity following pulmonary rehabilitation in COPD and provide complementary evidence to aid evaluations of interventions already attempted in this area, but also adds insight into future development of interventions targeting physical activity maintenance in COPD.