Abstract
We present the second release of value-added catalogues of the LAMOST Spectroscopic Survey of the Galactic Anticentre (LSS-GAC DR2). The catalogues present values of radial velocity Vr, ...atmospheric parameters – effective temperature Teff, surface gravity log g, metallicity Fe/H, α-element to iron (metal) abundance ratio α/Fe (α/M), elemental abundances C/H and N/H and absolute magnitudes MV and $M_{K_{\rm s}}$ deduced from 1.8 million spectra of 1.4 million unique stars targeted by the LSS-GAC since 2011 September until 2014 June. The catalogues also give values of interstellar reddening, distance and orbital parameters determined with a variety of techniques, as well as proper motions and multiband photometry from the far-UV to the mid-IR collected from the literature and various surveys. Accuracies of radial velocities reach 5 km s−1 for the late-type stars, and those of distance estimates range between 10 and 30 per cent, depending on the spectral signal-to-noise ratios. Precisions of Fe/H, C/H and N/H estimates reach 0.1 dex, and those of α/Fe and α/M reach 0.05 dex. The large number of stars, the contiguous sky coverage, the simple yet non-trivial target selection function and the robust estimates of stellar radial velocities and atmospheric parameters, distances and elemental abundances make the catalogues a valuable data set to study the structure and evolution of the Galaxy, especially the solar-neighbourhood and the outer disc.
Programmed cell death (PCD), referring to apoptosis, autophagy and programmed necrosis, is proposed to be death of a cell in any pathological format, when mediated by an intracellular program. These ...three forms of PCD may jointly decide the fate of cells of malignant neoplasms; apoptosis and programmed necrosis invariably contribute to cell death, whereas autophagy can play either pro‐survival or pro‐death roles. Recent bulk of accumulating evidence has contributed to a wealth of knowledge facilitating better understanding of cancer initiation and progression with the three distinctive types of cell death. To be able to decipher PCD signalling pathways may aid development of new targeted anti‐cancer therapeutic strategies. Thus in this review, we present a brief outline of apoptosis, autophagy and programmed necrosis pathways and apoptosis‐related microRNA regulation, in cancer. Taken together, understanding PCD and the complex interplay between apoptosis, autophagy and programmed necrosis may ultimately allow scientists and clinicians to harness the three types of PCD for discovery of further novel drug targets, in the future cancer treatment.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
The Y-stent technique, including crossing-Y and kissing-Y, is a promising therapeutic option for some complex bifurcation aneurysms. Here, its efficacy and safety are evaluated on the basis of 11 ...bifurcation aneurysms.
A retrospective review was conducted for all patients who underwent endovascular treatment of aneurysms in our department between January 2009 and June 2011 to identify and analyze cases with bifurcation aneurysms reconstructed by using Y-stents.
Eleven patients (4 ruptured and 7 unruptured aneurysms) were identified (4 men, 7 women) with a mean age of 60.4 years. Nine aneurysms (2 AcomAs, 3 MCA-Bifs, 1 PcomA, 3 BA apexes) were treated by using the crossing-Y technique, and 2 (both BA apexes) were treated with the kissing-Y technique, achieving complete occlusion in 6 aneurysms, residual neck in 4, and partial occlusion in 1. Perioperatively, a single thromboembolic event occurred in 1 case without neurologic deficit, which required a salvaging second stent implantation. Means of 9.9 months of angiographic and 13.7 months of clinical follow-up were available. As a result, 9 (81.8) aneurysms were completely occluded, 1 with a residual neck remained stable, and 1 residual aneurysm sac was recanalized, which was retreated and achieved a complete occlusion. All patients were independent with an mRS score of 0-1 at discharge and follow-up.
In selected patients, the reconstruction of bifurcation aneurysms by using the Y-stent can be successfully achieved with satisfactory midterm results.
•The effect geometric and flow parameters on the overall performance of DL-MCHS is studied.•The optimal width ratio of DL-MCHS is increased with the increase of channel aspect ratio.•Higher aspect ...ratio and smaller width ratio is suited to the situation when higher pumping power is provided.•The performance is improved by adjusting the velocity in upper channels to be lower than in bottom channels.
Microchannel is one of several high-heat-flux removal techniques being used in electronic cooling. Double-layered microchannel heat sink (DL-MCHS) with counter current flow arrangement is found not only to be able to lower the thermal resistance of the heat sink, but also decrease the maximum temperature and streamwise temperature rise on the base surface compared with single-layered microchannel heat sink (SL-MCHS). The present paper numerically investigated the thermal resistance, pumping power and temperature distribution on the base surface of substrate of DL-MCHS in different microchannel parameters and flow conditions, so as to find the complicated relationship between the overall performance of DL-MCHS and its geometric parameters and flow conditions. The numerical results show that the optimal width ratio of DL-MCHS should be increased when the microchannel aspect ratio is increased. The effectiveness of increasing aspect ratio of microchannels on improving the overall performance of DL-MCHS is dependent on the pumping power provided. DL-MCHS with higher aspect ratio and smaller width ratio is suited to the situation when higher pumping power is provided. Compared with the situation with identical inlet velocity being assigned to the bottom and upper microchannels, adjusting the inlet velocity of upper channels to be smaller than that of bottom channels may result in the improvement of the overall performance of DL-MCHS at a given pumping power, especially when the given pumping power is lower. These strategies could be tried in the real application of DL-MCHS.
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IMTLJ, KILJ, KISLJ, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
•Three-dimensional CFD model with forced air cooling are developed for battery modules.•Impact of different air cooling strategies on module thermal characteristics are investigated.•Impact of ...different model structures on module thermal responses are investigated.•Effect of inter-cell spacing on cell thermal characteristics are also studied.•The optimal battery module structure and air cooling strategy is recommended.
Thermal management needs to be carefully considered in the lithium-ion battery module design to guarantee the temperature of batteries in operation within a narrow optimal range. This article firstly explores the thermal performance of battery module under different cell arrangement structures, which includes: 1×24, 3×8 and 5×5 arrays rectangular arrangement, 19 cells hexagonal arrangement and 28 cells circular arrangement. In addition, air-cooling strategies are also investigated by installing the fans in the different locations of the battery module to improve the temperature uniformity. Factors that influence the cooling capability of forced air cooling are discussed based on the simulations. The three-dimensional computational fluid dynamics (CFD) method and lumped model of single cell have been applied in the simulation. The temperature distributions of batteries are quantitatively described based on different module patterns, fan locations as well as inter-cell distance, and the conclusions are arrived as follows: when the fan locates on top of the module, the best cooling performance is achieved; the most desired structure with forced air cooling is cubic arrangement concerning the cooling effect and cost, while hexagonal structure is optimal when focus on the space utilization of battery module. Besides, the optimized inter-cell distance in battery module structure has been recommended.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Artificial van der Waals heterostructures with two-dimensional (2D) atomic crystals are promising as an active channel or as a buffer contact layer for next-generation devices. However, genuine 2D ...heterostructure devices remain limited because of impurity-involved transfer process and metastable and inhomogeneous heterostructure formation. We used laser-induced phase patterning, a polymorph engineering, to fabricate an ohmic heterophase homojunction between semiconducting hexagonal (2H) and metallic monoclinic (1T') molybdenum ditelluride (MoTe2) that is stable up to 300°C and increases the carrier mobility of the MoTe2 transistor by a factor of about 50, while retaining a high on/off current ratio of 106. In situ scanning transmission electron microscopy results combined with theoretical calculations reveal that the Te vacancy triggers the local phase transition in MoTe2, achieving a true 2D device with an ohmic contact.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Abstract
Topology-protected surface transport of ultimate thinness in three-dimensional topological insulators (TIs) is breaking new ground in quantum science and technology. Yet a challenge remains ...on how to disentangle and selectively control surface helical spin transport from the bulk contribution. Here we use the mid-infrared and terahertz (THz) photoexcitation of exclusive intraband transitions to enable ultrafast manipulation of surface THz conductivity in Bi
2
Se
3
. The unique, transient electronic state is characterized by frequency-dependent carrier relaxations that directly distinguish the faster surface channel than the bulk with no complication from interband excitations or need for reduced bulk doping. We determine the topological enhancement ratio between bulk and surface scattering rates, i.e.,
γ
BS
/
γ
SS
~3.80 in equilibrium. The ultra-broadband, wavelength-selective pumping may be applied to emerging topological semimetals for separation and control of the protected transport connected with the Weyl nodes from other bulk bands.
We constructed a sample of 13,798 stars with Teff, log g, Fe/H, radial velocity, proper motions, and parallaxes from LAMOST DR5 and Gaia DR2 in the LAMOST Complete Spectroscopic Survey of Pointing ...Area (LaCoSSPAr) at the Southern Galactic Cap consisting of areas A and B. Using the distributions in both proper motions and radial velocity, we detected very significant overdensities in these two areas. These substructures most likely are portions of the Sagittarius (Sgr) stream. With the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm, 220 candidates stream members were identified. Based upon distance to the Sun and published models, 106 of these stars are likely to be the members of the Sgr stream. The abundance pattern of these members using /Fe from Xiang et al. were found to be similar to Galactic field stars with Fe/H < −1.5 and deficient to Milky Way populations at similar metallicities with Fe/H > −1.0. No vertical and only small radial gradients in metallicity along the orbit of the Sgr stream were found in our Sgr stream candidates.
Protein misfolding has been shown to be the direct cause of a number of highly devastating diseases such as Alzheimer's disease, Parkinson's disease, and Creutzfeldt-Jacob syndrome, affecting the ...aging population globally. The deposition in tissues of amyloid fibrils is a characteristic of all these diseases, and the mechanisms by which these protein aggregates form continue to be intensively investigated. In only a fraction of cases is an underlying mutation responsible, and accordingly, what initiates amyloid formation in vivo is the major question that is addressed. In this study, we show that membranes containing phosphatidylserine (PS), a negatively charged phospholipid, induce a rapid formation of fibers by a variety of proteins, viz., lysozyme, insulin, glyceraldehyde-3-phosphate dehydrogenase, myoglobin, transthyretin, cytochrome c, histone H1, and α-lactalbumin. Congo red staining of these fibers yields the characteristic light green birefringence of amyloid, and fluorescent lipid tracers further reveal them to include phospholipids. Our results suggest that PS as well as other acidic phospholipids could provide the physiological low-pH environment on cellular membranes, enhancing protein fibril formation in vivo. Interestingly, all the proteins mentioned above either are cytotoxic or induce apoptosis. PS−protein interaction could be involved in the mechanism of cytotoxicity of the aggregated protein fibrils, perturbing membrane functions. Importantly, our results suggest that this process induced by acidic phospholipids may provide an unprecedented and generic connection between three current major areas of research: (i) mechanism(s) triggering amyloid formation, (ii) cytotoxicity of amyloidal protein aggregates, and (iii) mechanism(s) of action of cytotoxic proteins.
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IJS, KILJ, NUK, PNG, UL, UM
We have cross-matched the LAMOST DR3 with the Gaia DR1 TGAS catalogs and obtained a sample of 166,827 stars with reliable kinematics. A technique based on the wavelet transform was applied to detect ...significant overdensities in velocity space among five subsamples divided by spatial position. In total, 16 significant overdensities of stars with very similar kinematics were identified. Among these, four are new stream candidates and the rest are previously known groups. Both the U-V velocity and metallicity distributions of the local sample show a clear gap between the Hercules structure and the Hyades-Pleiades structure. The U-V positions of these peaks shift with the spatial position. Following a description of our analysis, we speculate on possible origins of our stream candidates.
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