Polyamines play an important role in stress response. In the pathway of polyamines synthesis, S-adenosylmethionine decarboxylase (SAMDC) is one of the key enzymes. In this study, a full length cDNA ...of SAMDC (AhSAMDC) was isolated from peanut (Arachis hypogaea L.). Phylogenetic analysis revealed high sequence similarity between AhSAMDC and SAMDC from other plants.
In peanut seedlings exposed to sodium chloride (NaCl), the transcript level of AhSAMDC in roots was the highest at 24 h that decreased sharply at 72 and 96 h after 150 mM NaCl treatment. However, the expression of AhSAMDC in peanut leaves was significantly inhibited, and the transcript levels in leaves were not different compared with control
These results implied the tissue‐specific and time-specific expression of AhSAMDC. The physiological effects and functional mechanism of AhSAMDC were further evaluated by overexpressing AhSAMDC in tobaccos. The transgenic tobacco lines exhibited higher germination rate and longer root length under salt stress. Reduced membrane damage, higher antioxidant enzyme activity, and higher proline content were also observed in the transgenic tobacco seedlings. What's more, AhSAMDC also led to higher contents of spermidine and spermine, which can help to scavenge reactive oxygen species.
Together, this study suggests that AhSAMDC enhances plant resistance to salt stress by improving polyamine content and alleviating membrane damage
AhSAMDC subcloned into tobacco plants may play an important role in alleviating oxidative stress and membrane damages by improving antioxidant enzymes under salt stress.
Learning from a few examples (one/few-shot learning) on the fly is a key challenge for on-device machine intelligence. We present the first chip-level demonstration of one-shot learning with Stanford ...Associative memory for Programmable, Integrated Edge iNtelligence via life-long learning and Search (SAPIENS), a resistive random access memory (RRAM)-based non-volatile associative memory (AM) chip that serves as the backend for memory-augmented neural networks (MANNs). The 64-kb fully integrated RRAM-CMOS AM chip performs long-term feature embedding and retrieval, demonstrated on a 32-way one-shot learning task on the Omniglot dataset. Using only one example per class for 32 unseen classes during on-chip learning, SAPIENS achieves 79% measured inference accuracy on Omniglot, comparable to edge software model accuracy using five-level quantization (82%). It achieves an energy efficiency of 118 GOPS/W at 200 MHz for in-memory L1 distance computation and prediction. Multi-bank measurements on the same chip show that increasing the capacity from three banks (24 kb) to eight banks (64 kb) improves the chip accuracy from 73.5% to 79%, while minimizing the accuracy excursion due to bank-to-bank variability.
HIAF (High Intensity heavy ion Accelerator Facility), a new facility planned in China for heavy ion related researches, consists of two ion sources, a high intensity Heavy Ion Superconducting Linac ...(HISCL), a 45 Tm Accumulation and Booster Ring (ABR-45) and a multifunction storage ring system. The key features of HIAF are unprecedented high pulse beam intensity and versatile operation mode. The HIAF project aims to expand nuclear and related researches into presently unreachable region and give scientists possibilities to conduct cutting-edge researches in these fields. The general description of the facility is given in this article with a focus on the accelerator design.
To explore the clinical characteristics and prognosis of the new coronavirus 2019-nCoV patients combined with cardiovascular disease （CVD).
A retrospective analysis was performed on 112 COVID-19 ...patients with CVD admitted to the western district of Union Hospital in Wuhan, from January 20, 2020 to February 15, 2020. They were divided into critical group (ICU,
=16) and general group (
=96) according to the severity of the disease and patients were followed up to the clinical endpoint. The observation indicators included total blood count, C-reactive protein (CRP), arterial blood gas analysis, myocardial injury markers, coagulation function, liver and kidney function, electrolyte, procalcitonin (PCT), B-type natriuretic peptide (BNP), blood lipid, pulmonary CT and pathogen detection.
Compared with the general group, the lymphocyte count (0.74 (0.34, 0.94)×10
/L vs. 0.99 (0.71, 1.29)×10
/L,
=0.03) was extremely lower in the critical group, CRP (106.98 (81.57, 135.76) mg/L vs. 34.34 (9.55,76.54) mg/L,
<0.001) and PCT (0.20 (0.15,0.48) μg/L vs. 0.11 (0.06,0.20) μg/L,
<0.001) were significantly higher in the critical group. The BMI of the critical group was significantly higher than that of the general group (25.5 (23.0, 27.5) kg/m
vs. 22.0 (20.0, 24.0) kg/m
，
=0.003). Patients were further divided into non-survivor group (17, 15.18%) group and survivor group (95, 84.82%). Among the non-survivors, there were 88.24% (15/17) patients with BMI> 25.0 kg/m
, which was significantly higher than that of survivors (18.95% (18/95),
<0.001). Compared with the survived patients, oxygenation index (130 (102, 415) vs. 434 (410, 444),
<0.001) was significantly lower and lactic acid (1.70 (1.30, 3.00) mmol/L vs. 1.20 (1.10, 1.60) mmol/L,
<0.001) was significantly higher in the non-survivors. There was no significant difference in the proportion of ACEI/ARB medication between the critical group and the general group or between non-survivors and survivors （all
>0.05).
COVID-19 patients combined with CVD are associated with a higher risk of mortality. Critical patients are characterized with lower lymphocyte counts. Higher BMI are more often seen in critical patients and non-survivor. ACEI/ARB use does not affect the morbidity and mortality of COVID-19 combined with CVD. Aggravating causes of death include fulminant inflammation, lactic acid accumulation and thrombotic events.
Abstract
We report on analysis of observations of the bright transient X-ray pulsar Swift J0243.6+6124 obtained during its 2017-2018 giant outburst with Insight-HXMT, NuSTAR, and Swift observatories. ...We focus on the discovery of a sharp state transition of the timing and spectral properties of the source at super-Eddington accretion rates, which we associate with the transition of the accretion disk to a radiation pressure dominated (RPD) state, the first ever directly observed for magnetized neutron star. This transition occurs at slightly higher luminosity compared to already reported transition of the source from sub- to super-critical accretion regime associate with onset of an accretion column. We argue that this scenario can only be realized for comparatively weakly magnetized neutron star, not dissimilar to other ultra-luminous X-ray pulsars (ULPs), which accrete at similar rates. Further evidence for this conclusion is provided by the non-detection of the transition to the propeller state in quiescence which strongly implies compact magnetosphere and thus rules out magnetar-like fields.
In a semimetal, both electrons and holes contribute to the density of states at the Fermi level. The small band overlaps and multiband effects engender novel electronic properties. We show that a ...moderate hydrostatic pressure effectively suppresses the band gap in the elemental semiconductor black phosphorus. An electronic topological transition takes place at approximately 1.2 GPa, above which black phosphorus evolves into a semimetal state that is characterized by a colossal positive magnetoresistance and a nonlinear field dependence of Hall resistivity. The Shubnikov-de Haas oscillations detected in magnetic field reveal the complex Fermi surface topology of the semimetallic phase. In particular, we find a nontrivial Berry phase in one Fermi surface that emerges in the semimetal state, as evidence of a Dirac-like dispersion. The observed semimetallic behavior greatly enriches the material property of black phosphorus and sets the stage for the exploration of novel electronic states in this material.
Background
Vasculogenic mimicry (VM) is the formation of vascular channels by tumor cells or tumor cell-derived, trans-differentiated cells in highly aggressive, solid tumors. However, the disease ...features and prognostic value of VM for overall survival of cancer patients remain controversial.
Method
To systematically investigate the roles of VM in cancer progression and its prognostic values, we performed a meta-analysis based on 36 studies (33 eligible articles) including 3609 patients. The pooled hazard ratios (HRs) with 95 % confidence intervals (95 % CIs) were used to assess the relationship between VM and overall survival in cancer patients.
Results
Vasculogenic mimicry was significantly associated with cancer differentiation, lymph node metastasis, distant metastasis, and TNM stage. The prognostic value of VM was significant in overall survival (HR 2.16; 95 % CI 1.98–2.38;
P
< 0.001). Analyses stratified by confounders, such as cancer type, ethnicity, VM detection methods, sample size, and Newcastle–Ottawa quality score, found similar significant results.
Conclusions
The presence of VM predicts poorer survival outcomes in cancer patients.
► POSS nanoparticle was used as a novel coupled agent to enhance interface adhesion of PBO fibers with epoxy resin. The results show that octaglycidyldimethylsilyl POSS was grafted successfully on ...surface of PBO fibers. ► The surface morphology and surface chemical elemental composition of PBO fibers before and after modification were analyzed. ► The influence of POSS surface grafting on mechanical property and interfacial property of PBO fibers was investigated. Interfacial property was obviously enhanced, meanwhile mechanic property keep constant.
PBO fiber as reinforced material has been widely applied in various fields such as aerospace, automobile and sport apparatus due to excellent mechanic property during past two decades. However, poor interfacial adhesion limits the further application of PBO fiber. To solve this problem, plenty of work has been done. In the present study, the surface of PBO fibers was treated through surface grafting of polyhedral oligomeric silsequioxanes (POSS). The effect of POSS grafting on bulk mechanic property and interfacial property of PBO fiber were studied. Surface chemical composition, surface morphologies, surface free energy, single-fiber tensile strength of untreated and treated PBO fiber were characterized. The results show that POSS nanoparticles were grafted on the fiber surface successfully. The surface characteristics of treated PBO fiber were different from that of untreated one. Oxygen-containing polar functional groups, elemental ratio of oxygen to carbon, surface roughness and surface free energy increased significantly. In addition, interfacial shear strength between treated PBO fibers and epoxy resin increased to 54.9MPa comparative with untreated one. Meanwhile tensile strength of treated PBO fibers only very little decreased. Therefore, POSS surface grafting can be utilized to enhance the interfacial adhesion between PBO fibers and epoxy resin matrix.
Abstract
This study was made on domestic T1000 carbon fiber to investigate its surface condition, precursor, multifilament, fiber/resin contact angle, fiber/resin interfacial shear strength and ...interlaminar shear strength. Analysis was carried out to examine the surface physical state of domestic T1000 carbon fiber, the micro-scale interfacial properties and mechanical properties of the composites. The results show that domestic T1000 grade carbon fiber has no inherent characteristic defects such as visible bumps, rough edges or grooves on its surface. It can obtain higher tensile strength. The fiber/resin interfacial test shows that carboxylated carbon nanotubes are well dispersed in the epoxy resin matrix by physical method. The mixed resin matrix has good wettability on carbon fibers and the contact angle of the composite interface decreases. The interfacial shear strength of SYT65 carbon fibers/resin increases by 10.6%, and the interlaminar shear strength increases by 15.7%. Toray T1000 carbon fiber/resin interfacial shear strength increases by 6.1%, and interlaminar shear strength increases by 14.1%. Compared with Toray T1000, the resin system used in this study is more compatible with SYT65 carbon fiber, which can give full play to the mechanical properties of SYT65 carbon fiber.
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