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To meet the anti-interference and multi-function requirements of the antenna, a compact 8-states frequency reconfigurable ultra-wideband (UWB) monopole antenna is proposed. The antenna consists of a coplanar waveguide structure (CPW), defected ground structure (DGS), rectangular radiation patch, and stepped feed line. Band rejections at the C band, WLAN, and X band are generated by two C-slots and inverted U-slot, respectively. Three PIN diodes are connected across the C-slots and inverted U-slot. By controlling the on/off state of PIN diodes to realize notch reconfiguration. The antenna size is only 22 mm $\times 13$ mm $\times0.8$ mm. The measured results show that the antenna can work in 8 states. The impedance bandwidth of UWB mode is 2.82-13.25 GHz, the relative bandwidth is 129.8%. The notch band is 3.19-4.58 GHz, 5.26-6.21 GHz, and 7.87-8.73 GHz, respectively. The antenna has stable gain, good omnidirectional radiation performance, and can switch freely between UWB mode and each notch band mode.

Stroke imposes a substantial burden worldwide. With the rapid economic and lifestyle transition in China, trends of the prevalence of stroke across different geographic regions in China remain largely unknown. Capitalizing on the data in the National Health Services Surveys (NHSS), we assessed the prevalence and risk factors of stroke in China from 2003 to 2018. In this study, data from 2003, 2008, 2013, and 2018 NHSS were collected. Stroke cases were based on participants’ self-report of a previous diagnosis by clinicians. We estimated the trends of stroke prevalence for the overall population and subgroups by age, sex, and socioeconomic factors, then compared across different geographic regions. We applied multivariable logistic regression to assess associations between stroke and risk factors. The number of participants aged 15 years or older were 154,077, 146,231, 230,067, and 212,318 in 2003, 2008, 2013, and 2018, respectively, among whom, 1435, 1996, 3781, and 6069 were stroke patients. The age and sex standardized prevalence per 100,000 individuals was 879 in 2003, 1100 in 2008, 1098 in 2013, and 1613 in 2018. Prevalence per 100,000 individuals in rural areas increased from 669 in 2003 to 1898 in 2018, while urban areas had a stable trend from 1261 in 2003 to 1365 in 2018. Across geographic regions, the central region consistently had the highest prevalence, but the western region has an alarmingly increasing trend from 623/100,000 in 2003 to 1898/100,000 in 2018 (Ptrend

For the ultra‐wideband (UWB) transmission requirements in wireless communication systems and better miniaturization of mobile terminal antennas, a compact UWB multiple‐input multiple‐output (MIMO) antenna with higher isolation between units is proposed. The MIMO antenna consists of two semi‐circular antenna units and a defective ground structure. By improving the structure of the ground plane, the antenna units are placed upside down by taking advantage of the inherent directional radiation characteristics of the antenna units, thereby achieving higher isolation. The proposed antenna size is 15 × 22 × 1.6 mm3. The measurement results show that the proposed UWB MIMO antenna satisfies the port reflection coefficient S11

In this paper, we propose a wavelength converter, which is an expanded application of electrowetting liquid prism actuated in the micro-system. With two immiscible fluids in the transparent cell, we can actively control the shape of the fluid-fluid interface via electrowetting. Three different color filters are placed under the prism, and when we apply different voltages, light beam will through different filters because of the liquid prism's refraction. Our results show that we can obtain three different color lights from a non-transparent cap's light hole. The device is capable of reasonable switch time (∼75ms and ∼140ms).

A method of fabricating convex plate-shaped micro electrode was proposed based on the electrochemical etching principle. The square sectional electrodes were prepared in advanced using wire-EDM, The micro cylindrical electrode was fabricated firstly by using the eletrochechemical etching method. Then the top end was insulated to protect it from etching. Then the convex plate-shaped micro electrode was obtained in subsequent etching. Comparative experiments in drilling micro-hole in stainless steel with the thickness of 1mm were done by using the cylindrical and convex plate-shaped micro electrode. Results shows that the better locality, smaller side-gap and hole taper could be obtain by using convex plate-shaped micro electrode.

In this paper, we propose a Red Green Blue (RGB) converter, which is an expanded application of electrowetting liquid prism in the micro-systems. Four rectangular indium tin oxide (ITO) glass substrates having the same size are stacked to form the sidewalls. Another ITO electrode is fabricated and stuck on the bottom polymethyl methacrylate substrate as the opposite electrode. With two immiscible fluids in the transparent cell, the shape of the liquid–liquid interface can be deformed by electrostatic force. Three different color filters are placed under the prism. When we apply different voltages, the light beam will propagate through different filters by deforming the liquid–liquid interface. Our results show that we can obtain the light having three different colors from a non-transparent cap's light hole. The device is capable of reasonable switch time (~75 and ~140 ms). It has a wide potential application in tunable lasers, adaptive indicators, and display systems.

The present study was designed to assess the expression of microRNA-542-3p (miR-542-3p) in human colon cancer and investigate the possible molecular mechanisms underlying the effect of miR-542-3p on the growth and invasion of colon cancer cells. We found that miR-542-3p expression was downregulated in colon cancer patient tissues, compared with that observed in the control group. Silencing of miR‑542-3p expression significantly promoted cell viability and inhibited apoptosis. In addition, overexpression of miR-542-3p significantly reduced cell viability and promoted apoptosis in colon cancer cells. Meanwhile, silencing of miR-542-3p expression significantly suppressed PI3K and p-AKT and survivin protein expression, while overexpression of miR-542-3p significantly induced PI3K and p-AKT and survivin protein expression in colon cancer cells. PI3K inhibitor (LY294002) or survivin inhibitor (YM155) suppressed PI3K/AKT/survivin signaling and increased the anticancer effects of miR-542-3p on the apoptosis in colon cancer. The present study demonstrated that upregulation of miR-542-3p inhibited the growth and invasion of colon cancer cells through PI3K/AKT/survivin signaling, highlighting a novel therapeutic approach for the treatment of colon cancer.

Venous thromboembolism (VTE) has significant clinical implications in leukemia patients. However, the actual frequency of this complication remains unknown. We performed a systematic review and meta-analysis to better estimate the frequency of this complication and to assess the risk factors that contribute to its occurrence. We searched several databases, including PubMed, Embase, and Web of Science, and assessed study quality using the Newcastle–Ottawa scale. The pooled frequency of VTE in leukemia patients was calculated. A total of 144 studies met the eligibility criteria. The incidence rate (IR) of VTE from 72 prospective studies comprising 9,061 patients was 5% (95%CI: 4–6%). The incidence rate (IR) of VTE in ALL, CLL, total-AML, and CML population was 5% (95%CI: 4–6%), 3% (95%CI: 2–5%), 6% (95%CI: 4–8%) and 13% (95%CI: 1–36%). The incidence of VTE was markedly decreased among ALL patients who received anticoagulation treatment (IR: 1%, 95%CI: 0–6%) or concentrates therapy (IR: 3%, 95%CI: 0–9%). The overall incidence of VTE in the leukemia population was high, particularly in transplant recipients, who had the highest risk (IR: 8%, 95% CI: 4–13%). Prophylactic approaches could significantly decrease the occurrence of VTE events.

In this letter, we demonstrate a mirror reflector actuated by a liquid droplet. Four rectangular polymethyl methacrylate substrates are stacked to form the device structure. Three ITO electrodes are fabricated on the bottom substrate. One droplet is placed on the middle of the substrate and is surrounded by silicone oil. One side of the mirror is adhered to a rotating axis and the other side is immersed in the droplet. When we apply a voltage to one side of the ITO electrode, the droplet stretches and moves toward this side of the substrate surface and pushes the mirror to rotate. When illuminated by a light beam, the mirror reflector can function as a beam steering and detecting device. Our experiments show that the mirror reflector can deflect and steer the light within an angle of 0°-60° (±30°) as the applied voltage is changing from 0 to 65 V. The proposed device has potential applications in many fields such as free-space optical communications and laser detections.

In this letter, we report an adjustable optical slit using two immiscible liquids, including an opaque liquid and a clear liquid. The opaque liquid is conductive, whereas the clear liquid is insulating. The opaque liquid is divided into two droplets, which are surrounded by the clear liquid. In the voltage- off state, the two droplets keep away from each other. When a voltage is applied to the device, the two droplets move in opposite directions and form a slit-like opening due to force balance between electrostatic force and charge repelling force. Our results show that the width of the slit can be tuned from ~ 160 to ~ 570 μm as the applied voltage is changed from ~ 40 to ~ 80 V. The shape deforming response time of the droplets and the transmittance in the opening area were measured to be ~ 390 ms and ~ 86%, respectively. Our optical slit has potential applications in spectrophotometers, line spread functions, and masking.

Neurofibrillary pathology of abnormally hyperphosphorylated tau is a hallmark of Alzheimer's disease (AD) and other tauopathies. Phosphatidylinositol 3-kinase (PI3K)/Akt/glycogen synthase kinase-3 beta (GSK-3β) signaling pathway is pivotal for tau phosphorylation. Inhibition of soluble epoxide hydrolase (sEH) metabolism has been shown to effectively increase the accumulation of epoxyeicosatrienoic acids (EETs), which are cytochrome P450 metabolites of arachidonic acid and have been demonstrated to have neuroprotective effects. However, little is known about the role of sEH in tau phosphorylation. The present study investigated the role of a sEH inhibitor, 1-(1-propanoylpiperidin-4-yl)-3-[4-(trifluoromethoxy)phenyl] urea (TPPU), on H

Micro-electrode preparation is the key technology in micro-machining of micro- mechanics and micro-parts. In this research, the machining method of micro-pin using micro-electrochemical machining (micro-ECM) was proposed. The principle of micro-pin fabrication is introduced and the studies are focused on the effects of varies parameters on the shape of the micro-pin. The theoretic model between the shape of micro-pin and the parameters including power, voltage, duty ratio of pulse power, immerge depth of electrode is built up and then verified by experimentations. Experimental results denote that the micro-electrode with desirable shape and size could be prepared by controlling applied parameters. When the immersing depth is deeper, the pulse power, low voltage and duty ratio is proper selected. On the contrary, the DC power or pulse power with higher voltage and duty ratio should be applied. Finally, micro-pin with diameter of 5μm and 60μm long was fabricated when the DC power of 1.8V voltage and immersing depth of 1mm is applied.

Due to the mutual radiation impedance may influence acoustics performance of a broadband dense plane array seriously, the expression of mutual radiation impedance among the transducers is developed according to the definition of mutual radiation impedance based on BEM（Boundary Element Method）. BEM model is established for acoustic radiation of a broadband dense plane array with nine elements. Sound pressure distribution of the nine-element array is solved using SYSNOISE software. And mutual radiation impedances are calculated on the condition of knowing surface normal velocity. Acoustic performance of the nine-element array is analysed through mutual radiation impedance. The influence of mutual impedance on acoustics performance for nine-element array is verified by comparing with measured curve of transducer conductance. The results show that it is successful to calculate mutual impedance of the array and predict acoustics performance using BEM.

In this study the prediction of the erosion profiles during ECM of the spiral hole was presented. By assumptions, the major points were simplified into one-dimensional problems. The theoretical and computational model was built to illustrate the profile movement as the time elapses. The analysis was based on the law of electrolysis and the software MATLAB was used. Verifications were done through experiments and the deviation was 7.5% between theoretical and experimental result. On the basis of the prediction of the erosion profile, the applied parameters could be estimated.

Diamond wire saw is the leading technology for use in slicing hard brittle material. This paper provides a brief review of its research progress in the most recent years. According to the bonding material kinds of diamond wire saw, it can be classified into three main categories, i.e. metallic bonding materials, organic bonding materials, and resin bonding materials. In the past decade, several new major technical developments in fixed abrasive diamond wire saw have emerged. This paper investigates the related literature on four different types of fixed abrasive diamond wire saws, presents their manufacturing processes and machining performance, and compares the tension and anti-abrasion of the wire saws, removal efficiency of slicing, and their applications in silicon slicing.

The numerical simulation and experiment had been applied to study the cooling of electric cutting tool. Temperature and wind velocity vector of three-dimensional cooling duct were obtained by Fluent. From the numerical simulation, the stagnation flow, reflow and backset which resulted in the poor cooling condition of the electric cutting tool were discussed. By modifying ribs, partition and outlet, a new cooling duct was reconstructed. The cooling effect of the new cooling duct was better than the original one by the experiment test.

Electrochemical machining (ECM) technology has the advantage of machining the workpiece with complex profile on the basis of electrolysis. In this study, turbulated holes with the rib’s shape of spiral and annular were processed by ECM by using the shaped cathodes. Experimental system was built which consists of electrolyte supply module, power supply unit and workpiece holding device. Machining experimentations were carried out on the built system. Analysis and discussions were done according to the experimental results. It indicated machining efficiency is high by using the shaped cathode. Machining error could be controlled within 10-20%.

The machining of materials on microscopic scales is considered to be great importance to a wide variety of fields. Electrochemical Micro-machining (EMM) appears to be promising to machine the micro-structures in future due to the material is dissolved at the unit of ion. This paper is focused on developing a micro electrochemical machining system in which the micro-structures such as micro-cylinder, multiple micro-electrodes, micro-holes and micro-slot were processed. The micro-electrodes were prepared in a precisely controlling the electrochemical etching process. Mathematical model controlling the diameters of electrodes was built up. Furthermore, the obtained micro-electrodes were selected as the cathode tool for micro holes drilling and micro-slot milling using pulse power in Micro-ECM.

Diamond wire saw is the leading technology for use in cutting hard brittle material. Its smaller kerf and faster cutting time make it replacing the conventional slurry technology for those materials. Turned over the traditional router, this paper presents a novel approach that replaces the typical metallic core with a nonmetallic core, for manufacturing of ultraviolet curing resin fixed-abrasive diamond wire saw (DWS). The experiments show that the diamond wire saw made by this manufacturing method can obtain a good performance as well as taking many other advantages.

The bioactive, signaling lipid, sphingosine-1-phosphate (S1P), and its analog, fingolimod (FTY720), have previously shown neuroprotective effects against ischemic brain injury. However, the underlying mechanisms have not yet been fully clarified. The roles of autophagy in ischemic stroke are being increasingly recognized. In the present study, we sought to determine whether the S1P pathway is involved in neuronal autophagy and investigate its possible mechanisms following stroke. Interestingly, we found that FTY720 significantly attenuates infarct volumes and reduces neuronal apoptosis on days 1 and 3 post stroke, accompanied by amelioration of functional deficits. Additionally, FTY720 was found to decrease the induction of autophagosome proteins, microtubule-associated protein 1 light chain 3(LC3-II) and Beclin1, following ischemic stroke in a dose-dependent manner. Meanwhile, protein levels of the mammalian target of rapamycin (mTOR) and the 70-kDa ribosomal protein, S6 kinase1 (p70S6K), were also up-regulated in FTY720-treated animals, and the nonspecific SphK inhibitor, N,N-dimethylsphingosine (DMS), was found to cause a reverse effect. Our results indicate that modulation of the S1P signaling pathway by FTY720 could effectively decrease neuronal autophagy through the mTOR/p70S6K pathway and attenuate ischemic brain injury in mice.

In this paper we report an adaptive liquid lens actuated by droplet movement. Four rectangular PMMA (Polymethyl Methacrylate) substrates are stacked to form the device structure. Two ITO (Indium Tin Oxide) sheets stick on the bottom substrate. One PMMA sheet with a light hole is inserted in the middle of the device. A conductive droplet is placed on the substrate and touches the PMMA sheet to form a small closed reservoir. The reservoir is filled with another immiscible non-conductive liquid. The non-conductive liquid can form a smooth concave interface with the light hole. When the device is applied with voltage, the droplet stretches towards the reservoir. The volume of the reservoir reduces, changing the curvature of the interface. The device can thus achieve the function of an adaptive lens. Our experiments show that the focal length can be varied from −10 to −159 mm as the applied voltage changes from 0 to 65 V. The response time of the liquid lens is ~75 ms. The proposed device has potential applications in many fields such as information displays, imaging systems, and laser scanning systems.

The aim of the present study was to investigate the influence of osmotic pressure on myocardial contractility and the possible mechanism. Electrical stimulation was used to excite papillary muscles of the left ventricle of Sprague-Dawley (SD) rats. The contractilities of myocardium in hyposmotic, isosmotic, and hyperosmotic perfusates were recorded. The influences of agonist and antagonist of the transient receptor potential vanilloid 4 (TRPV4) on the contractility of myocardium under hyposmotic, isosmotic and hyperosmotic conditions were observed. The results were as follows: (1) Compared with that under isosmotic condition (310 mOsm/L), the myocardial contractility was increased by 11.5%, 21.5% and 25.0% (P0.05) under hyposmotic conditions when the osmotic pressure was at 290, 270 and 230 mOsm/L, respectively; and was decreased by 16.0%, 23.7% and 55.2% (P0.05) under hyperosmotic conditions when the osmotic pressure was at 350, 370 and 390 mOsm/L, respectively. (2) When ruthenium red (RR), an antagonist of TRPV4, was added to the hyposmotic perfusate (270 mOsm/L), the positive inotropic effect of hyposmia was restrained by 36% (P0.01); and when RR was added to the hyperosmotic perfusate (390 mOsm/L), the inhibitory effect of hyperosmia on myocardial contractility was increased by 56.1% (P0.01). (3) When 4-α-phorbol-12,13-didecanoate (4α-PDD), an agonist of TRPV4, was added to the isosmotic perfusate (310 mOsm/L), the myocardial contractility did not change; and when 4α-PDD was added to the hyperosmotic perfusate (390 mOsm/L), the inhibition of myocardial contractility by hyperosmia was increased by 27.1% (P0.01). These results obtained indicate that TRPV4 is possibly involved in the osmotic pressure-induced inotropic effect.

We demonstrate a 1×2 optical switch matrix based on a liquid-actuated mirror reflector. Three indium tin oxide (ITO) electrodes are fabricated on the bottom substrate. One droplet is placed in the middle of the liquid channel and surrounded by density-matched silicone oil. A mirror reflector is placed on the droplet. In its initial state, the light beam can pass through the device from the light hole. When we apply voltage to one side of the ITO electrode, the droplet carries the mirror reflector, stretching and moving toward this side of the substrate. Therefore, the light beam is reflected by the mirror reflector. The light beam can pass through the device again when the mirror reflector is carried away by the droplet. Out-1 and Out-2 alternately change the switch-on and off states. Therefore, the device can achieve the function of a 1×2 optical switch matrix. Because it uses a mirror reflector to block the light beam, the device can attain 100% intensity attenuation. Our experiments show that the switch time from Out-1 (Out-2) to Out-2 (Out-1) are 129 and 123 ms, respectively. The proposed optical switch has potential applications in variable optical attenuators, electronic displays, and light shutters.

We propose a 1×2 optical switch based on electrowetting effect. The proposed optical switch is composed of a black liquid and a clear liquid. The black liquid is placed in the center of the bottom substrate. The surrounding is filled with transparent oil. The bottom substrate is fabricated with three abreast indium tin oxide electrodes. When we apply a voltage to one side of the electrode, the droplet stretches toward the same side of the substrate. When the voltage is removed, the droplet returns to its original state with the aid of interfacial tension and adsorption force. In our experiment, it requires ∼52 and ∼250 ms for the device to switch the light off and on, respectively. The maximum optical attenuation can reach ∼29 dB and the minimum power consumption is 14.9 μW. When we apply a voltage to the both sides of the electrodes, the device can achieve the function of light-on and light-off states simultaneously. The proposed optical switch has potential applications in optical switching networks, variable optical attenuators, and optical routers.

An adaptive liquid iris for an optical switch based on electrowetting is demonstrated. The device consists of a clear conductive liquid and an opaque insulate oil. In the voltage-off state, the dome of the clear liquid touches the top substrate, and an iris-like opening is formed in its central area, and the aperture of the opening is at its largest. When a voltage is applied to the device, the shape of the conductive liquid is deformed due to the electrowetting effect. As a result, the diameter of the opening is reduced. Our results show that the aperture of the device can be tuned from similar to 6.4 mm to 0 as the applied voltage is changed from 0 to similar to 60 V. The device can obtain a high optical attenuation (similar to 872:1). The response time was measured to be similar to 117 ms (shrinking time is similar to 25 ms, and relaxing time is similar to 92 ms) with turnaround speed of 55 mm/s. Our device has potential applications in light shutters, variable optical attenuators, adaptive irises, and displays. (C) 2014 Society of Photo-Optical Instrumentation Engineers (SPIE)