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To understand the density, populations and habitats of malaria vectorThe malaria vectorDuring the period from 2005 through 2019, the malaria vectorThe population structure of malaria vector

As the fourth most common malignant tumor with high mortality rate, gastric cancer (GC) seriously threatens people's health and life quality worldwide. The aim of this study was to explore the functional role of long non-coding RNA (lncRNA) BCAR4 in GC.Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) assay was used to detect the expression level of lncRNA BCAR4 in GC cell lines and tissues. Subsequently, cell counting kit-8 (CCK-8) assay, colony formation assay, and flow cytometry were recruited to investigate the role of lncRNA BCAR4 in the proliferation and apoptosis of GC cells, respectively. Western blotting was used to detect the protein expression level of mitogen-activated protein kinase (MAPK)/extracellular-signal-regulated kinase (ERK) in GC. Besides, tumor formation assay was applied to examine the ability of lncRNA BCAR4 in vivo.LncRNA BCAR4 was highly expressed in both GC tissues and cell lines. CCK-8 assay, colony formation assay, and flow cytometry results indicated that up-regulated lncRNA BCAR4 significantly promoted cell proliferation and suppressed cell apoptosis in GC. Besides, over-expression of lncRNA BCAR4 could activate the MAPK/ERK signaling pathways. Tumor xenograft formation assay demonstrated that over-expression of lncRNA BCAR4 promoted tumor formation in vivo.LncRNA BCAR4 was proved significantly up-regulated in GC. Over-expression of lncRNA BCAR4 promoted cell proliferation and suppressed cell apoptosis in vitro and promoted tumor formation in vivo. Besides, Western blotting revealed that lncRNA BCAR4 played an oncogenic role in GC via regulating MAPK/ERK signaling.

Some studies have confirmed that long non-coding ribonucleic acids (lncRNAs) played a vital role in the pathophysiology of various diseases, especially in oncogenesis and progression of tumors. Dysexpressed lncRNAs regulate different cellular processes, including proliferation, invasion, and apoptosis. The aim of this study was to explore the clinical significance and function of lncRNA MIR4435-2HG in colorectal cancer.Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to detect the expression of lncRNA MIR4435-2HG. The Kaplan-Meier method was used to evaluate the overall survival and disease-free survival of patients with colorectal cancer. The cell proliferation was measured by Methyl thiazolyl tetrazolium (MTT) assay. The cell apoptotic rate was measured via flow cytometry method.LncRNA MIR4435-2HG is a novel cancer-related lncRNA that was recently found to exhibit high expression in colorectal cancer. The dysregulation of lncRNA miR4435-2HG was significantly related to the tumor size (p0.001), lymph node metastasis (p0.001), and tumor node metastasis (TNM) staging (p=0.022). The patients with higher expression of lncRNA miR4435-2HG showed worse prognosis than those with low expression of lncRNA miR4435-2HG group. Besides, the downregulated lncRNA miR4435-2HG expression could repress cell proliferation and enhance cell apoptosis.LncRNA MIR4435-2HG functions as an oncogene that promotes colorectal cancer progression, and likely represents a biomarker or therapeutic target of colorectal cancer.

SiC/Gr/Al composites with the graphite particle size of 1, 6 and 20 μm were fabricated by squeeze casting technology and the effects of graphite particles on machinability were investigated. Results show that with increasing size of graphite particles, the tool wear has very little change, but the cutting force decrease noticeably. Compared to SiC/Al composite, the cutting forces increase steadily with increasing the cutting speed during machining SiC/Gr/Al composite, the tool life is prolonged 42 and 59%, respectively, at speed of 20 and 30 m min− 1 when machining SiC/Gr(6 μm)/Al composite. It is a result of the solid lubrication of graphite particle preventing for growth of adhesive wear.

The electrical resistivity of liquid Bi–Ga alloys has been measured in both heating and cooling process using the four‐probe method. Anomalous behaviours of resistivity with temperature appear in heating process and are irreversible in subsequent cooling process. Microheterogeneity is then proved to exist in the melt during heating and depicted by the emulsion model. The evolution of heterogeneity in liquid Bi33·3Ga66·7 alloy was investigated through both isothermal and non‐isothermal experiments. The results indicate that Bi33·3Ga66·7 melt experiences a polydisperse–monodisperse–homogeneous state transformation upon successive heating above critical temperature.

Accurate conversion of wideband multi-GHz analog signals into the digital domain has long been a target of analog-to-digital converter (ADC) developers, driven by applications in radar systems, software radio, medical imaging, and communication systems. Aperture jitter has been a major bottleneck on the way towards higher speeds and better accuracy. Photonic ADCs, which perform sampling using ultra-stable optical pulse trains generated by mode-locked lasers, have been investigated for many years as a promising approach to overcome the jitter problem and bring ADC performance to new levels. This work demonstrates that the photonic approach can deliver on its promise by digitizing a 41 GHz signal with 7.0 effective bits using a photonic ADC built from discrete components. This accuracy corresponds to a timing jitter of 15 fs - a 4-5 times improvement over the performance of the best electronic ADCs which exist today. On the way towards an integrated photonic ADC, a silicon photonic chip with core photonic components was fabricated and used to digitize a 10 GHz signal with 3.5 effective bits. In these experiments, two wavelength channels were implemented, providing the overall sampling rate of 2.1 GSa/s. To show that photonic ADCs with larger channel counts are possible, a dual 20-channel silicon filter bank has been demonstrated.

Sampling rates of high-performance electronic analog-to-digital converters (ADC) are fundamentally limited by the timing jitter of the electronic clock. This limit is overcome in photonic ADC’s by taking advantage of the ultra-low timing jitter of femtosecond lasers. We have developed designs and strategies for a photonic ADC that is capable of 40 GSa/s at a resolution of 8 bits. This system requires a femtosecond laser with a repetition rate of 2 GHz and timing jitter less than 20 fs. In addition to a femtosecond laser this system calls for the integration of a number of photonic components including: a broadband modulator, optical filter banks, and photodetectors. Using silicon-on-insulator (SOI) as the platform we have fabricated these individual components. The silicon optical modulator is based on a MachZehnder interferometer architecture and achieves a VπL of 2 Vcm. The filter banks comprise 40 second-order microring-resonator filters with a channel spacing of 80 GHz. For the photodetectors we are exploring ion-bombarded silicon waveguide detectors and germanium films epitaxially grown on silicon utilizing a process that minimizes the defect density.

Pressure sensitive adhesives (PSA) were prepared by copolymerization of butyl acrylate, methyl methacrylate and styrene macromer and the effects of macromer on the adhesive properties and phase separated structures were investigated. The results are as follows: (1) The cohesion of the PSA increased as the quantity of the styrene macromer increased. (2) The reason why the cohesion of the PSA increased seemed to be that the polystyrene phase, as the graft chain, was separated from the polybutyl acrylate phase as matrix. (3) When styrene was used instead of styrene macromer, there were not these effects on the adhesive properties.

A broadband, Mach-Zehnder-interferometer based silicon optical modulator is demonstrated, with an electrical bandwidth of 26 GHz and V(pi)L of 4 V.cm. The design of this modulator does not require epitaxial overgrowth and is therefore simpler to fabricate than previous devices with similar performance.

We present a systematic study of Mach-Zehnder silicon optical modulators based on carrier-injection. Detailed comparisons between modeling and measurement results are made with good agreement obtained for both DC and AC characteristics. A figure of merit, static VpiL, as low as 0.24Vmm is achieved. The effect of carrier lifetime variation with doping concentration is explored and found to be important for the modulator characteristics.

We present a comprehensive study of silicon Mach-Zehnder modulators based on carrier injection. Detailed comparisons between simulation results and measurements are made and excellent agreement is obtained for DC and AC characteristics.

A high-speed silicon optical modulator has been demonstrated which can operate either in forward bias using carrier injection, or in reverse bias using carrier depletion. In forward bias, the device requires less than 10 mW of drive power, but has a low bandwidth of 100 MHz. In reverse bias, the device has a nearly flat response to 18 GHz, but requires 700 mW for large modulation depths.

Photonic Analog-to-Digital Conversion (ADC) has a long history. The premise is that the superior noise performance of femtosecond lasers working at optical frequencies enables us to overcome the bottleneck set by jitter and bandwidth of electronic systems and components. We discuss and demonstrate strategies and devices that enable the implementation of photonic ADC systems with emerging electronic-photonic integrated circuits based on silicon photonics. Devices include 2-GHz repetition rate low noise femtosecond fiber lasers, Si-Modulators with up to 20 GHz modulation speed, 20 channel SiN-filter banks, and Ge-photodetectors. Results towards a 40GSa/sec sampling system with 8bits resolution are presented.

A Mach-Zehnder based silicon optical modulator has been demonstrated with a bandwidth of 26 GHz and a VπL of 2 V·cm. The design of this modulator does not require an epitaxial overgrowth.

The object is construction of a thermohydrodynamic theory of thrust bearings. The bearing pad has the geometry of an annular sector and is supported in one point; about this point it is free to pivot. The film shape is arbitrary, thus permitting specification of thermal-elastic deformation and/or crowning of the pad. The lubricant which is interposed between bearing pad and runner has temperature dependent viscosity. The lubricant flow may be laminar or turbulent. The numerical method employed in this work is the method of Finite Differences for the pressure equation and Galerkin’s method with B-spline test functions for the energy equation.

This is Part II, of a three-part sequence of papers on pivoted thrust pads. In this paper we apply the thermohydrodynamic theory of Part I to statically loaded, sector shaped pivoted thrust pads. The film shape is arbitrary and pad deformation can be specified once the geometry of the pad and the geometry of its support system are known. Presently we assume spherical crowning of the pad: crowning presents us with an opportunity to discuss film cavitation and its effects. Spherical-crowning is advantageous to employ, because it can be represented by a single parameter and because it yields the approximate shape of a loaded pivoted pad.