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The Tibetan Plateau (TP) is important for weather and climate. Relatively clean aerosol conditions over the Plateau makes the study on the aerosol-cloud-precipitation interactions in this region distinctive. A convective event with precipitation observed on 24 July 2014 in Naqu was selected to explore the influence of aerosols on the onset and intensity of precipitation. We use the Modern-Era Retrospective analysis for Research and Applications Version 2 (MERRA-2) reanalysis to derive the cloud condensation nuclei (CCN), which can be regarded as the real-time background. These values are adopted to initialize the regional WRF 4.0 meteorological model and to simulate the onset of convective events and the formation of precipitation. Four sets of experiments were adopted for our simulations. A detailed analysis of microphysical processes shows that, with the increase in the aerosol number concentration, the conversion rate of cloud water to rain in clouds is enhanced at first. Under polluted situation, the conversion process of cloud water to rain is suppressed; however, the transformation of cloud water to graupel and the development of convective clouds are favored. As a result, the onset of the precipitation is delayed and cold-rain intensity increases.

Background:Emerging evidence shows that serum biomarkers are closely associated with the prognosis of gastric cancer. Cachexia represents systemic nutritional and metabolic statuses. This study aimed to clinically validate the predictive value of serum biomarkers and cachexia, and to identify a potential biomarker for the early diagnosis of cachexia. Methods: This study included patients with gastric cancer who received curative treatment with no other nonneoplastic cachexia. The eligible population was randomized into training (70%) and test (30%) cohorts.A univariate and multivariate Cox proportional-hazards regression model was used to construct a gastric cancer prognosis model. The predictive and discriminative abilities of the model were evaluated using Kaplan–Meier (K–M) and receiver operating characteristic (ROC) curves. A nomogram was constructed based on the factors identified using the prognostic model, and the corresponding calibration curve was used to validate the accuracy of the nomogram. Exosomal microRNAs (miRNAs) were screened for the early diagnosis of cachexia via whole-genome sequencing, and the clinical samples were used for verification. Results: This study included 1101 eligible patients with gastric cancer. There were 330 (29.97%) patients with cachexia and 771 (70.03%) without cachexia. Univariate Cox regression analysis identified the following prognostic factors: body mass index; cachexia; nutritional risk screening scale-2002 (NRS2002) score; serum albumin, carcinoembryonic antigen (CEA), carbohydrate antigen 19-9(CA19-9), and carbohydrate antigen 125 (CA125) levels, and red blood cell count. Multivariate Cox regression analysis identified cachexia and CEA, CA19-9, and serum albumin levels as the independent risk factors for overall survival (OS;p < 0.05). The K–M curve indicated that the OS of high-risk patients was significantly lower than that of low-risk patients. The areas under the curve of the 1-, 2-, and 3-year prognostic models were 81.13%, 78.49%, and 76.23%, respectively (79.01%, 78.61%, and 75.34% for the test cohort, respectively). Finally, the corresponding nomogram was used to predict the OS of patients with gastric cancer. The calibration curve showed the best agreement between predictions and actual observations. Furthermore, plasma exosomal miR-432-5p was identified as a biomarker for the early diagnosis of cachexia via whole-gene sequencing to make up for the lack of methods for the early diagnosis of cachexia. Conclusions: Serum biomarker levels and cachexia status are clinically significant in patients with gastric cancer. We constructed a novel prognostic model based on serum biomarker levels and cachexia. A novel nomogram constructed using this model may predict OS in patients with gastric cancer alone. Furthermore, we identified a novel plasma exosomal biomarker, miR-432-5p, for the early diagnosis of cachexia.

The Tibetan Plateau (TP) is of great importance for weather and climate due to its role as heat and water resource. Relatively clean aerosol conditions over the Plateau makes the study on the aerosol-cloud-precipitation interactions in this pristine continental region distinctive. In order to investigate the impacts of aerosols on small-scale convection processes over the TP, a convective event with precipitation observed on 24 July 2014 in Naqu was selected to explore the influence of aerosols on the onset and intensity of precipitation. We use the MERRA-2 reanalysis to derive the cloud condensation nuclei (CCN) , which can be regarded as the real-time background. These values are adopted to initialize the regional WRF 4.0 meteorological model and to simulate the onset of convective events and the formation of precipitation. Four sets of experiments, named clean (1/10 CCN), control (default setting), Tibetan Plateau (real CCN calculated from MERRA-2 analysis), and polluted (10 times CCN), were adopted for our simulations. A detailed analysis of microphysical processes shows that, with the increase in the aerosol number concentration, the conversion rate of cloud water to rain in clouds is first enhanced. Under polluted situations, the conversion process of cloud water to rain is suppressed; however, the transformation of cloud water to graupel and the development of convective clouds are favored. As a result, the onset of the precipitation is delayed and cold-rain intensity increases.

As a typical difficult-to-machine composite material, the microfabrication process of printed circuit board (PCB) is widely studied, especially the micro-hole drilling. However, multi-layer PCBs composed of flat glass fiber reinforced polymer and high-hardness ceramic particle fillers exhibit different tool wear behavior during the micro-hole drilling. The results showed that the abrasive wear on the chisel edge and main cutting edge are observed in the drilling of multi-layer PCB, while fracture of the main cutting edge only occurred in the drilling of ceramic particle filled GFRPs. Increasing the feed rate or spindle speed could effectively reduce tool wear. The cold air auxiliary drilling can effectively reduce the flank wear of the micro-drill, especially in the drilling of multi-layer PCBs.

DNA damage-regulated autophagy modulator 1 (DRAM1) is required for induction of autophagy and apoptosis. However, the influence of DRAM1 on the pathogenesis of inflammatory bowel disease (IBD) has not been explored. DRAM1 expression was examined in the intestinal mucosa of patients with IBD and colons of colitis mice. We used a recombinant adeno-associated virus carrying small hairpain DRAM1 to knock down the DRAM1 gene to treat colitis in the mice. The effect of DRAM1 on autophagy and apoptosis of intestinal epithelial cells was explored. DRAM1-mediated interaction with the c-Jun N-terminal kinase (JNK) pathway was also examined. DRAM1 expression in the intestinal mucosa of the IBD patients was higher than that in the control participates. DRAM1 expression in the inflammatory cells in patients with Crohn’s disease (CD) was lower than that in patients with ulcerative colitis (UC). Additionally, DRAM1 expression was correlated with the Simple Endoscopic Score for CD and the Mayo endoscopic score for UC. Serum levels of DRAM1 in the IBD group were substantially higher than those in the normal group. The knockdown of DRAM1 could alleviate colitis symptoms in mice. In in vitro experiments, knocking down DRAM1 could reduce autophagy and apoptosis levels. Mechanistically, DRAM1 may participate in the regulation of these two processes by positively regulating JNK activation. During intestinal inflammation, the upregulation of DRAM1 may promote the activation of JNK and further aggravate intestinal epithelium damage.

Skeletal muscle is responsible for the majority of glucose disposal in the body. Insulin resistance in the skeletal muscle accounts for 85–90% of the impairment of total glucose disposal in patients with type 2 diabetes (T2D). However, the mechanism remains controversial. The present study aims to investigate whether AKT2 deficiency causes deficits in skeletal muscle development and metabolism, we analyzed the expression of molecules related to skeletal muscle development, glucose uptake and metabolism in mice of 3- and 8-months old. We found that AMP-activated protein kinase (AMPK) phosphorylation and myocyte enhancer factor 2 (MEF2) A (MEF2A) expression were down-regulated in AKT2 knockout (KO) mice, which can be inverted by AMPK activation. We also observed reduced mitochondrial DNA (mtDNA) abundance and reduced expression of genes involved in mitochondrial biogenesis in the skeletal muscle of AKT2 KO mice, which was prevented by AMPK activation. Moreover, AKT2 KO mice exhibited impaired AMPK signaling in response to insulin stimulation compared with WT mice. Our study establishes a new and important function of AKT2 in regulating skeletal muscle development and glucose metabolism via AMPK-dependent signaling.

Although both biodiesel and n-butanol are excellent renewable biofuels, most of the existing research works merely use them as the additives for petroleum diesel. As the main fuel properties of biodiesel and n-butanol are complementary, the biodiesel/ n-butanol blends are promising to be a pure biomass-based substitute for diesel fuel. In this paper, the application of the biodiesel/ n-butanol blends on an agricultural diesel engine was comprehensively investigated, in terms of the combustion, performance, and emission characteristics. First, the biodiesel/ n-butanol blends with 10%, 20%, and 30% n-butanol by weight were prepared and noted as BBu10 (10 wt% n-butanol + 90 wt% biodiesel), BBu20 (20 wt% n-butanol + 80 wt% biodiesel), and BBu30 (30 wt% n-butanol + 70 wt% biodiesel). It was found that adding 30 wt% n-butanol to biodiesel can reduce the viscosity by 39.3% and increase the latent heat of vaporization by 57.3%. Then the engine test results showed that with the addition of n-butanol to biodiesel, the peak values of the cylinder pressure and temperature of the biodiesel/ n-butanol blends were slightly decreased, the peak values of the pressure rise rate and heat release rate of the blends were increased, the fuel ignition was delayed, and the combustion duration was shortened. BBu20 has the approximate ignition characteristics with diesel fuel. Both the brake thermal efficiency and the brake-specific fuel consumption of BBu30 were increased by the average percentages of 2.7% and 14.9%, while NO x, soot, and CO emissions of BBu30 were reduced by the average percentages of 17.6%, 34.1%, and 15.4%, compared to biodiesel. The above variations became more evident as the n-butanol proportion increased.

Interfacial energy storage contributes a new mechanism to the emergence of energy storage devices with not only a high-energy density of batteries but also a high-power density of capacitors. In th...

In this paper, biodiesel was used to upgrade bio-oil by extracting the high-quality fuel fractions in bio-oil through solvent extraction. After the extraction, the upper layer blends of biodiesel and the high-quality bio-oil components, also called the “extraction phase liquid”, was obtained and denoted as EPBB. Firstly, Thermogravimetric (TG) and Fourier transform infrared (FTIR) analyses indicated that the light components originally in bio-oil, such as alcohols, ethers, ketones and carboxylic acids were extracted from bio-oil to biodiesel and formed the EPBB. Then the fuel properties of EPBB were measured at different temperatures. The results showed that the density of EPBB was higher, while its viscosity, surface tension and lower heating value (LHV) were lower than those of biodiesel. Accordingly, EPBB revealed better atomization and evaporation characteristics as compared to biodiesel. Finally, the engine performance of EPBB was tested on an unmodified direct-injection diesel engine. When compared with biodiesel, the ignition delay of EPBB was longer, the premixed combustion duration was longer, while the total combustion duration was shorter. The fuel economy of EPBB was comparable to that of biodiesel, and the NOx, soot, CO and UHC emissions of EPBB were all lower than those of biodiesel.

Hybrid lithium-ion supercapacitors combine the advantages of both the high power density of capacitors and the high energy density of lithium batteries, where activated carbon serves as a critical ...

Intercalation of carbon nanosheets into two-dimensional (2D) inorganic materials could enhance their properties in terms of mechanics and electrochemistry, but sandwiching these two kinds of materi...

This paper presents a combined experimental and numerical study on the fuel deposition characteristics during the Port fuel injection (PFI) spray impingement process. The numerical models mainly consisted of a newly developed atomization model, the Senda spray impingement model, and the Bai-Gosman liquid film model. A group of measurement methods were used to hierarchically calibrate and validate the numerical models. It was found that the calibrated models were able to predict the time-resolved morphology of the impinging spray, as well as the shape, area, and thickness distribution of the deposited fuel film with a good reliability. Then the calibrated models were used to study the effects of impingement distance ( Lw) and impingement angle ( θw) on the fuel film deposition. The results showed that as Lw increases, the film area ( Af) and film mass ( mf) rise faster and reach higher final values. As θw increases, Af and mf grow slower, and their final values are hugely reduced. Increasing Lw and decreasing θw can effectively reduce the average film thickness ( hf,a). Af is mainly affected by the contact area between the spray plumes and the impinging wall, while mf is also affected by the dominant droplet-wall interaction regime.

Aqueous supercapacitors represent an extremely attractive candidate for next-generation energy storage devices, attributed to their excellent high-power density, low cost, nonflammability and environmental friendliness. Nonetheless, compared with their nonaqueous counterparts, the main challenge of aqueous supercapacitors lies in their narrow operating cell voltages and lower energy densities. Here we demonstrate that such issues can be overcome via optimizing the electrolyte and electrode materials by using high concentration “water-in-salt” electrolyte and low electrocatalytic activity all-pseudocapacitive metal-oxide electrodes, respectively. The high operating voltage of 2.2 V can be achieved for hybrid supercapacitor with MnO2 and Fe3O4 as positive and negative electrode, combining with a “water-in-salt” electrolyte. This hybrid supercapacitor exhibits a maximum specific energy of 35.5 Wh kg total − 1 at a specific power of 151.9 W kg total − 1 based on the mass of total activate materials. In addition, the hybrid system retains 87% of its initial specific energy even after 3000 charge/discharge cycles.

The roots of Stephania tetrandra are used as a traditional Chinese medicine. Isoquinoline alkaloids are considered to be the most important and effective components in this herb, but little is known about the molecular mechanism underlying their biosynthesis. In this context, this study aimed to reveal candidate genes related to isoquinoline alkaloid biosynthesis in S. tetrandra. Determination of tetrandrine and fangchinoline in the roots and leaves of S. tetrandra by HPLC showed that the roots had much higher contents of the two isoquinoline alkaloids than the leaves. Thus, a comparative transcriptome analysis of the two tissues was performed to uncover candidate genes involved in isoquinoline alkaloid biosynthesis. A total of 71 674 unigenes was obtained and 31 994 of these were assigned putative functions based on BLAST searches against 6 annotation databases. Among the 79 isoquinoline alkaloid-related unigenes, 51 were differentially expressed, with 42 and 9 genes upregulated and downregulated, respectively, when the roots were compared with the leaves. The upregulated differentially expressed genes were consistent with isoquinoline alkaloid accumulation in roots and thus were deemed key candidate genes for isoquinoline alkaloid biosynthesis in the roots. Moreover, the expression profiles of 10 isoquinoline alkaloid-related differentially expressed genes between roots and leaves were validated by quantitative real-time polymerase chain reaction, which indicated that our transcriptome and gene expression profiles were reliable. This study not only provides a valuable genomic resource for S. tetrandra but also proposes candidate genes involved in isoquinoline alkaloid biosynthesis and transcription factors related to the regulation of isoquinoline alkaloid biosynthesis. The results lay a foundation for further studies on isoquinoline alkaloid biosynthesis in this medicinal plant.

Interfacial energy storage contributes a new mechanism to the emergence of energy storage devices with not only a high-energy density of batteries but also a high-power density of capacitors. In this study, success was achieved in preparing a highly ordered two-dimensional (2D) carbon/TiO

Intercalation of carbon nanosheets into two-dimensional (2D) inorganic materials could enhance their properties in terms of mechanics and electrochemistry, but sandwiching these two kinds of materials in an alternating sequence is a great challenge in synthesis. Herein, we report a novel strategy to construct TiO

By coupling the Wu-Faeth (WF) turbulent primary breakup theory with the classical Kelvin-Helmholtz (KH) and Rayleigh-Taylor (RT) aerodynamic instability theories, the influences of nozzle-generated turbulence and aerodynamic force on the GDI spray atomization were both modeled in this study. The developed WF-KH-RT model was applied to the spray simulation of a six-hole GDI injector. The model calibration showed that with a simple tuning of a few model parameters, the WF-KH-RT model could predict the spray morphology, spray tip penetration (STP) and Sauter Mean Diameter (SMD) under various injection pressure and ambient pressure conditions with a high fidelity. The influences of specific WF-KH-RT model parameters on the spray simulation were also studied. The results revealed that increasing the KH characteristic time constant B1, WF characteristic length constant Csx and RT characteristic length constant CRT will lead to the increase of STP and SMD under most conditions. As the ratio of fuel density to ambient density ρ f / ρ g decreases, the aerodynamic effect is enhanced while the turbulent effect is weakened in the primary breakup, as a result the sensitivity of STP and SMD to B1 increases, while that to Csx declines. In summary, the results of this study can provide an insight into the relationship between different mechanisms affecting the fuel spray atomization, and an instruction of calibrating the proposed novel atomization model in GDI engine spray simulations.

A skeletal chemical kinetic model for the simulation of auto-ignition and flame propagation characteristics of primary reference fuel (PRF) was developed. Coupled with this model, 3D simulations were applied to investigate the influence of lubricant oil droplets on pre-ignition in a turbocharged direct-injection spark-ignition (DISI) engine at low-speed high-load operating conditions. First, a simulation study on the influence of a lubricant oil droplet on auto-ignition of gasoline substitute and air mixture was performed in a constant-volume chamber. The results revealed that with an increase of the lubricant oil droplet diameter, the ignition delay time for the air/fuel mixture initially decreased and then increased. The ignition delay time was further shortened with the increase of the temperature of the lubricant oil droplet and the temperature and pressure of the mixture. Moreover, it was found that when n-heptane (n-C7H16) was used as a substitute for the direct evaporation product of the lubricant oil droplet, the shortening of the ignition delay time for the air/fuel mixture caused by lubricant oil evaporation was not enough to initiate pre-ignition. When octyl hydrogen peroxide ketone (C8KET) was chosen as a representative of the accumulated stable reactive radicals, the ignition delay time was significantly shortened and was short enough to trigger pre-ignition. Therefore, pre-ignition may not be induced by the direct evaporation product of an lubricant oil droplet but by the accumulated stable reactive radicals. A simulation study on auto-ignition and flame propagation of the air/fuel mixture with the presence of a lubricant oil droplet was then conducted in a turbocharged DISI engine. The results successfully predicted the auto-ignition of the air/fuel mixture near the lubricant oil droplet before the spark ignition timing. Finally, a more convincing mechanism for pre-ignition induced by lubricant oil droplets is proposed to provide some clues for further investigation.

Poor rate capability and cyclability are the major barriers to using TiO2 as the next generation anode material for high-performance lithium-ion batteries. In this study, a sandwich-like composite consisting of atomically defined two-dimensional (2D) carbon nanosheet is constructed by the confined synthesis in the galleries of layered TiO2 nanosheet with the superior cycling and rate performances as the anode material for lithium-ion batteries. It is first experimentally revealed that the interfacial charge storage between unilamellar TiO2 nanosheet and carbon nanosheet in the Carbon/TiO2 nanosheet stack and the excellent structure stability during the discharge/charge process contribute to the superior performance of the composites. The resultant composite exhibits a high specific capacity (568 mAh g−1) with a specific energy of 407.4 Wh kg−1 at a specific power of 71.7 W kg−1, and remains 88.0 Wh kg−1 at a specific power of 9.0 kW kg−1. Apart from promising lithium-ion battery anode, this 2D Carbon/TiO2 composite also has immense potential for applications in other areas such as sodium/potassium-ion batteries, supercapacitor, and catalysis.

In this study, we report the fabrication of garnet-structure composited solid-state electrolyte with high compactness as a water-proof interlayer for multilayer water-proof protected-lithium-anode. It is revealed that with the addition of Li3BO3 into the sintering precursor, the cubic phase garnet Li6.75La3Zr1.75Nb0.25O12 with high lithium ion conductivity and compactness can be achieved at a low temperature of 1000 °C with a “binder-like” Li3BO3 glassy molten phase in the grain boundary, indicating Li3BO3 plays an important role on the densification of grain boundary and the improvement of the relative density. 50 mol % Li6.75La3Zr1.75Nb0.25O12–Li3BO3 pellet shows a high lithium ion conductivity of 2.08 × 10−4 S cm−1 and a good chemical stability in 21 m LiTFSI “water-in-salt” electrolyte at 25 °C. Hybrid lithium ion capacitor using this garnet-ceramic electrolyte as interlayer for water-proof protected-lithium-anode, 21 m LiTFSI electrolyte and commercial activated carbon as the cathode shows a high working voltage of 4.0 V and a high energy density of 228.9 Wh (kg-carbon)−1 at a power density of 1343.2 W (kg-carbon)−1.

In this work, an experimental study on the effects of the impingement geometry, the cross-flow intensity and the wall temperature on the characteristics of an impinging port fuel injection (PFI) spray was conducted. The transient development of the impinging spray was recorded by a high-speed camera with Mie scattering. Based on the high-speed images, the spray tip penetration (S) and the impinged spray height (Hw) were obtained. The results show that with the increase of the impingement distance (Lw), S increases and Hw decreases at the same time after the impingement. As the impingement angle (θw) increases, S decreases while Hw first increases and then decreases. With the increase of the cross-flow velocity (Uc), less part of the spray impinges onto the wall, and S significantly increases. As the wall temperature (Tw) rises, S does not show much variation. However, Hw increases gently for Tw lower than 420 K, and it increases sharply for Tw higher than 420 K due to the Leidenfrost mechanism. The effects of the above factors (Lw, θw, Uc, Tw) on S and Hw were finally evaluated and compared through the introduction of a contribution index.

We present the temporal evolution of magnetic field topology in the magnetotail with a southward IMF in order to identify the magnetic reconnection. The magnetic field topology is uniquely determined by the eigenvalues of the critical points, if they are not degenerated. This is because the critical points, their number, and the rules between them characterize the whole magnetic field pattern. At the critical points, the magnetics become zero. The magnetic vector field curves and surfaces are both integrated out along the principal directions of certain classes of critical points including the Earth’s dipole magnetic field. The skeleton that includes the critical points, characteristic curves, and surfaces provides the three-dimensional topological structure of the reconnection. The change of the skeleton, i.e. the change of the topology, has revealed the occurrence of magnetic reconnection. Namely, three-dimensional “X-points” or the more-than-two critical points that are saddle and connected each other are unstable and can move, vanish, and generated.

The Motion of charged particle in magnetotail-like reversal field with time dependent electric field is studied analytically and numerically using a test particle approach. Variations in the solar wind magnetic and/or velocity can induce a time-dependent electric field in the magnetotail. Interaction of the magnetotail particles with this electric field can give rise to stochasticity. Energy coupling from the field to the plasma is due to stochastic motion of the particles and is termed “stochastic heating” or “stochastic acceleration”. The stochasticity can lead to heating of the plasma and to strong particle acceleration. The process can provide an explanation to the difference between ion and electron temperatures in the plasma sheet.