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A dual-dc output three-phase three-level ac–dc converter is proposed for low-frequency pulsed power decoupling applications. One of the dc output is connected to the dc pulsed load, whereas the other one is used as power decoupling port and connected to the decoupling capacitor. The voltage of the power decoupling dc port can vary in a wide range to reduce the value and volume of the power decoupling capacitor. A buck/boost converter is employed to interface the power decoupling port with the dc pulsed load. A modified space vector pulsewidth modulation strategy is proposed for the ac–dc converter, based on which independent voltage and power regulation of the two dc outputs is achieved. The steady-state power is directly fed to the dc load with single power conversion stage, and the low frequency pulse power is fed to the power decoupling port. As a result, high-power quality and efficient power decoupling with reduced power conversion stages are achieved. Operation principles, modulation, and control strategies of the ac–dc converter are analyzed in detail. A prototype is built and tested to verify the effectiveness and feasibility of the proposed ac–dc converter for pulsed load.

In this article, a hybrid connected unified power quality conditioner integrating distributed generation (HCUPQC-DG) is proposed. Two dc ports are created at the dc link of the HCUPQC-DG, in which one low-voltage (LV) dc port is directly connected to distributed generation (DG), and the other high-voltage (HV) dc port is indirectly connected to DG through the front-end dc–dc converter. With the hybrid connected configuration, the HV is designed to ensure the dc–ac voltage conversion capability, whereas the LV, i.e., the voltage of DG, can be relatively low and vary in a wide range. Besides, most active power can be directly transferred from DG to the ac load or grid through the direct power flow path. Hence, the conversion efficiency is enhanced, and the power capacity of the front-end dc–dc converter is significantly reduced. The operating principle and the control and modulation strategies of the proposed HCUPQC-DG are discussed. Moreover, the power flow through the HCUPQC-DG is analyzed in detail to understand the system operation. Experimental results with a 3-kVA prototype are provided to verify the feasibility and effectiveness of the proposed HCUPQC-DG.

A hybrid three-phase ac/dc power system, which is composed of a diode-bridge rectifier and a two-stage ac–dc converter, is proposed in this article, for low-frequency pulsed load applications. With the proposed hybrid power system, the low-frequency pulsed load power is decoupled with the average power of the ac source, while the high-frequency harmonics induced by the diode-bridge rectifier is compensated by the ac–dc converter. Fault-tolerant operation is achieved with four possible operation modes of the proposed hybrid power system. Therefore, high reliability is achieved with these redundant operation modes. Operation principles, control methods, and design considerations of the hybrid ac/dc power system are analyzed in detail. An experimental prototype is built and tested to verify the effectiveness and feasibility of the proposed hybrid ac/dc circuit and its control strategy.

Instantaneous hardware protection is a very important method to protect inverters at the moment of over current or short circuit fault. For standalone inverters, the hardware protection can also be modified to achieve current limiting during the over current or short-circuit period. In conventional cycle by cycle (CBC) current protection, all switches of the inverter are turned OFF immediately when current is higher than the over current threshold. However, it may lead to protection being triggered frequently and high di/dt in switches and diodes, which will do harm to the reliability of the inverter. To solve this issue, a new CBC current limiting method is proposed, which turns off partial switches of the inverter. The operation principle of the conventional method and the presented method are detailed analyzed with switching states and implementation circuits given. In addition, the presented method is verified by an engineering prototype, and experimental results verified the effectiveness of the proposed method.

Background: Yes-associated protein(YAP) plays an important role in signal transduction and gene transcription regulation in 1 normal cells, with elevated and over-expressed YAP levels observed in various malignant tumors. The aim of this study was 2 to investigate the expression of YAP in malignant glioma, and to study the possible relationship of YAP expression with the 3 occurrence and development of malignant glioma. 4 Methods: Immunohistochemical staining was used to assess the expression of YAP and phosphor-YAP in malignant glioma 5 tissue and normal brain tissue, and their protein and mRNA levels were evaluated through Western blotting and reverse 6 transcription-polymerase chain reaction (RT-PCR), respectively. Normal brain tissue obtained from the functional lesion of 7 the epilepsy patients. After transfection of YAPsiRNA oligonucleotides or pcDNA3.1-hYAP plasmid, their effects on glioma 8 cells were investigated using western blot, cell proliferation, cycle, apoptosis and invasion, respectively. We conducted the 9 2 co-Immunoprecipitation to verify the combination of YAP and PPARγ, explore the mechanism of action. 10 Results: YAP-positive expression was found in 9 cases of normal brain and 60 cases of glioma. A significantly higher 11 expression of YAP in glioma tissue as compared with normal brain tissue at both protein and mRNA levels, and YAP proteins 12 mainly expressed and located in the nucleus and only a small percentage in the cytoplasm of glioma tissue. Phosphor-YAP 13 protein expression showed high staining of the cytoplasm, but no staining of the nuclear. While, with the enhancement of 14 the malignant degree, the cytoplasm YAP(p-YAP) expression is lower gradually than normal brain tissues. Further study in 15 glioma cell lines in which YAP was either overexpressed or depleted confirmed that YAP markedly promoted the cell 16 proliferation, cycle, invasion and inhibited the cell apoptosis. Moreover, YAP in company with PPARγ regulates the cell 17 proliferatin and effects the gliomagenesis. 18 Conclusion: These results indicate that YAP plays an important role in glioma and might be a useful therapeutic target of 19 glioma. 20

BACKGROUND To investigate the preventive effect of elastic stockings on deep vein thrombosis (DVT) after orthopedic surgery by literature search and meta-analysis. METHODS PubMed, Embase and Cochrane were selected as the search database platforms to search the literature of randomized controlled trials related to elastic stockings and DVT published from 2008 to date. Revman 5.3.5 software was used for statistical analysis of the data to obtain forest and funnel plots. RESULTS In this study, 90 studies were initially screened and 7 were finally included, covering a total of 3,116 patients. Meta-analysis showed that the 7 studies had statistical heterogeneity (I2=32%, P=0.18), so a random effect model was used. The obtained statistic was [odds ratio (OR) =0.59, 95% confidence interval (CI): (0.34, 1.03)], the statistical effect size was Z=1.84, P=0.07, and the difference was not statistically significant, so a stepwise sensitivity analysis was performed by the exclusion method. One study was excluded, and the remaining 6 showed homogeneity (I2=0%, P=0.46). They were analyzed by subgroup according to the type of operation: ankle surgery or hip and knee arthroplasty. The internal literatures of each subgroup were homogeneous: ankle surgery subgroup (I2=0%, P=0.43), hip and knee arthroplasty subgroup (I2=0%, P=0.88). Therefore, fixed effect mode analysis was used, and the effect size of elastic stockings after ankle surgery was Z=3.65, P=0.0003, while the effect size of elastic stockings in the hip and knee arthroplasty subgroup was Z=1.23, P=0.22. DISCUSSION Elastic stockings had an obvious preventive effect on DVT in patients undergoing ankle surgery, but not in patients undergoing lumbar, knee or spinal surgery. It is necessary to combine anticoagulant drugs and other physical therapies to prevent DVT.

Pregnancy is a special period marked with complicated changes in various immune responses. Although pregnant women are prone to developing gingival inflammation, its immunological mechanism remains to be clarified. In a modified ligature-induced periodontal disease murine model, pregnant mice developed more severe alveolar bone loss. Using this model, we investigated the Treg responses during exacerbated periodontal disease in pregnant mice. We tested Treg-associated molecules in gingival tissues by quantitative real-time PCR and found decreased gingival expression of Foxp3, TGFβ, CTLA-4, and CD28 in pregnant mice after periodontal disease induction. We further confirmed that lower number of Treg cells were present in the cervical lymph nodes of pregnant periodontitis mice. Treg cells from the cervical lymph nodes of ligated pregnant mice and non-pregnant mice were tested for their suppressive function in vitro. We manifested that Treg suppressive function was also down-regulated in the pregnant mice. Additionally, we demonstrated that more inflammatory Th17 cells were present in the cervical lymph nodes of ligated pregnant mice. Therefore, impaired Treg development and function, together with upregulated Th17 response, may contribute to the exacerbated periodontal disease during pregnancy.

Differences between heat-assisted magnetic recording (HAMR) and conventional perpendicular magnetic recording at narrow track widths are compared. We can see that HAMR appears to have similar adjacent track interference, but increased readback signal from the adjacent tracks (side reading). This background interference signal appears to be a consequence of the media architecture, and can be decreased if the media soft underlayer spacing to the hard layer, and transducer is reduced. The impact is also reduced for very high linear densities, due to a smaller fraction of unbiased flux from the neighbor tracks reaching the test track. The use of two reader multiple sensor magnetic recording at high track density appears to address some of this issue, and we can demonstrate viable track writing for HAMR beyond 1M tracks per inch using this readback technique.

A hybrid three-phase AC/DC power system composed of a passive rectifier and an active two-stage AC/DC rectifier is researched for low-frequency pulsed load applications. The non-pulsation part of the load power is processed by the passive rectifier while the pulsation part is regulated by the active rectifier. Therefore, both high efficiency and high reliability is achieved by adopting the hybrid structure. Meanwhile, with the help of the active rectifier, the high peak value pulsed power is decoupled with the AC source, and the high frequency harmonics generated by the passive rectifier is compensated as well. As a result, the negative impact of the pulsed power on the AC source is suppressed effectively. The operation principles of hybrid AC/DC power system and its control strategy is analyzed and investigated in detail. A prototype is built and tested to verify the effectiveness and feasibility of the hybrid AC/DC power system.

BACKGROUND Deep venous thrombosis (DVT) is a common postoperative complication in patients with lower limb fractures. This study aims to investigate the predictive value of plasminogen activator inhibitor-1 (PAI-1), fibrinogen (FIB), and D-dimer (D-D) for DVT following lower limb traumatic fracture surgery and to investigate risk factors for DVT. METHODS Clinical data of 63 patients who underwent lower limb traumatic fracture surgery in our hospital from September 2018 to March 2019 were retrospectively analyzed. Patients were divided into a DVT group and a non-DVT group. The differences in the levels of plasminogen activator inhibitor-1 (PAI-1), fibrinogen (FIB), and D-dimer (D-D) were compared, and a receiver operating characteristic (ROC) curve was used to analyze their predictive value for DVT following surgery for lower limb traumatic fracture. Multiple logistic regression analysis was used to analyze the risk factors of DVT. RESULTS The levels of PAI-1, FIB, and D-D in the DVT group were higher on the third day after surgery compared to the pre-surgical levels, and were also higher than those in the non-DVT group (P

Ischemic stroke causes severe brain damage and remains one of the leading causes of morbidity and mortality worldwide. The microRNA-134 (miR-134) is involved in regulating the process of ischemia injury in neural cells and brain with ischemia stroke. The role of miR-134 in ischemic stroke remains poorly understood. The purpose of the current study was to investigate the effect of bone marrow-derived mesenchymal stem cells (BMSCs)-derived exosomal miR-134 on rat oligodendrocytes (OLs) apoptosis and its underlying mechanism of action. The results demonstrated that levels of miR-134 in BMSCs-exosome decreased but increased incaspase-8 after oxygen-glucose deprivation (OGD) treatment. Exosomal miR-134 significantly inhibited apoptosis by decreasing caspase-8 expression and activity in OGD-treated group cultured with BMSCs-exosome and OLs. In addition, the miR-134 mimics decreased caspase-8 expression in OGD-treated OLs, whereas miR-134 inhibitors exacerbated the changes in the expression of the procaspase-8 and caspase-8 cleaved product proteins caused by OGD. The caspase-8 knockdown using caspase-8 small interfering RNA decreased OLs apoptosis, reversing the improvements that the miR-134 inhibited cells apoptosis by targeting caspase-8. Taken together, these results demonstrated that BMSCs-derived exosomes suppressed OLs apoptosis through exosomal miR-134 by negatively regulating the caspase-8-dependent apoptosis pathway and may, therefore, be a novel potential therapeutic target for ischemic stroke treatment.

An active clamping circuit for voltage sharing among series-connected insulated gate bipolar translators (IGBTs) during turning-on process is proposed at first, which detects the C-E voltage of the leading IGBT and generates gate pumping current to slow down the turning-on speed, and thus reduces the voltage difference between the IGBTs. Then, a turn-on edge regulation algorithm for the driving signal is proposed, which further reduces the voltage spike and turn-on power loss, and optimises the regulation speed. A time detection circuit is introduced to detect the pulse signal indicating the working time of the active clamping circuit for driving signal regulation. The turn-on edge regulation for each IGBT is determined by the feature that the rising edge of the detected pulse signal coincides with the corresponding IGBT turn-on edge delay. The experimental results prove the feasibility and effectiveness of the proposed method.

Haliotis discus hannai Ino is one of the important mariculture species in China. Presently, H. discus hannai is extensively cultured in two coastal provinces in China, Shandong in the north and Fujian in the south, and is usually cultured in the “North-South Relay” mode. In order to simulate the growth of abalone in the north and south, an individual dynamic energy budget (DEB) model was constructed for abalone. Model simulation was done by STELLA software, using water temperature and food consumption as forcing functions, with 18 energy budget-related parameters. The DEB model was then validated by field data collected in a Relay-culture operation in 2017 to 2018. Model simulation revealed that, the simulated growth of abalone in non-relay culture scenarios was significantly lower than that in the Relay mode. In Sanggou Bay (in the north) and Xiuyu Sea (in the south), the shell length and dry flesh weight reached 6.3 cm and 10 g, or 5.29 cm and 4.6 g, respectively, as a result of simulated growth for 365 d of abalone seedlings at 2.8 cm and 0.3 g. While the abalone growth in Relay-culture reached a shell length of 6.8 cm and dry flesh weight of 10.9 g. Growth simulations by the DEB model in both length and weight were within the range of observations for abalone. And several goodness-of-fit indices (R-square, modeling efficiency and Theil's inequality coefficient) showed that the DEB model of abalone was able to reproduce abalone growth with acceptable accuracy. By simulating the growth of abalone in aquaculture under different environmental scenarios, the rationale behind the Relay-culture mode was proved at the individual organism level.

To explore the clustered voltage balancing mechanism of the star-connected cascaded H-Bridge (SCHB) STATCOM, this paper analyzes the relationship between the active power and the control variables—modulation reference voltages in a dq frame through positive and negative sequence component decomposition. The derived relationship in the dq frame reveals that the negative sequence modulation reference voltage is capable of redistributing the active power among three phases and also the SCHB STATCOM features the clustered voltage self-stabilizing without any additional clustered voltage balancing control. To eliminate the differences of three clustered voltages, a new clustered voltage balancing control is proposed by regulating negative sequence modulation reference voltage in the dq frame. Its balancing mechanism is analyzed in detail and a simple implementation is presented as well. The effectiveness of the proposed control is verified by experimental results on a 400 V/15 kvar SCHB STATCOM.

In this paper, the improved asymptotic solutions of eigenmodes (leaky and Berenger modes) are provided for a circular waveguide terminated by a perfectly matched layer. Furthermore, a systematic asymptotic approach is developed by the inverse power series. Numerical simulations demonstrate that the high-precision asymptotic eigenmodes can be obtained.

A multifunctional compensator based on a three-phase bidirectional AC/DC converter for the AC power system with low-frequency pulsed load is evaluated in this paper. Both high-frequency harmonics and low-frequency pulsed power are compensated by the compensator. The control method and modulation strategy are analyzed in detail, as well as the design consideration of the energy storage capacitor. In the end, feasibility and performance of this multifunctional compensator are evaluated by the simulation and experimental results.

To widen the applications of large-diameter prestressed high-strength concrete (PHC) piles to stiff strata, this paper introduces a novel hybrid piling technique, including the equipment an...

For the modal computation of an open optical waveguide with a varying refractive-index profile, two perfectly matched layers are used to terminate the waveguide, and the refractive-index profile is approximated by a piecewise polynomial of degree two. Then, the corresponding Sturm–Liouville problem (eigenvalue problem) of the Helmholtz operator in each layer can be solved analytically by the Whittaker functions, and the analytical approximate dispersion equations are established for both TE and TM cases. The approximate solutions converge fast to the exact ones for the continuous refractive-index function as the maximum value of the subinterval sizes tends to zero. Numerical simulations show that high-precision modes may be obtained by Muller’s method with suitable initial values. The validation of the proposed method is also verified by use of the finite difference method with a fine grid.

The embedded mask patterning (EMP) process provides a potential L10-FePt media solution for 1–10 Tbit/in2 magnetic recording areal density level. Methanol/Ar reactive ion etch process of FePt media (Ru 2 nm/FePt 8 nm) in EMP is investigated using an ion-neutral-redep synergy etch rate model with the consideration of sputtered redeposition. It has been found that etching of high aspect ratio features spacing that is largely limited by its low etch rate due to high redeposition rate; etching of small size grains is mostly limited by hard mask erosion through the etching process. This would cause etch non-uniformity within the grain size and grain spacing distribution. The hard mask on top of the small size grains (i.e., less than 3 nm) erodes much faster than the larger size gains, resulting in a completely consumed mask before the underlying layers are reached. It is important to reduce local ion sputtering in order to minimize mask erosion for the small grains. We have found that a higher chemical etch selectivity (>30:1) is essential to minimize mask erosion on the grains of 2 nm or larger. We also report that when sputter yield of Ru mask and FePt is adjusted from $10^{-1}$ to $10^{-2}$ level, further improvement is observed with the patterned grain size down to 2.5 nm and spacing down to 1.5 nm, and we suggest that the use of etch gas chemistry with a lighter atomic weight (such as He instead of Ar) would allow for sub-10 nm grain patterning.

Heat dissipation in LED light bulb has been one of the key factors in affecting the efficiency and lifetime of the LED. The commercially available high-power LED light bulbs often come with a bulky heatsink to keep the temperature of the light bulb in a reasonable range. Unfortunately, the heatsink designs of most of the commercial products are not optimized in terms of cooling efficiency, dimension, and material cost. Indeed, optimization of the heatsink design is a time-consuming and sophisticated process. It requires a powerful computational fluid dynamics tool to perform computer simulation. With the aid of computer simulation based on a simple heat conduction model together with some measurement results, this work presents a rapid evaluating tool for predicting the peak temperature of a heatsink by using the concept of effective heat conductivity. It provides a simple way to predict the peak temperature change for different designs.

Background Previous studies showed the aberrant expression of microRNA-182 (miR-182) in glioma tissue. However, the exact role of circulating miR-182 in glioma remains unclear. Here, we confirmed the expression of plasma circulating miR-182 in glioma patients, and further explored its potential diagnostic and prognostic value. Material/Methods Real-time quantitative PCR (RT-PCR) was used to measure circulating cell-free miR-182 from 112 glioma patients and 54 healthy controls. Results Our findings showed that the level of circulating miR-182 in glioma patients was higher than that in healthy controls (P

Rationale The improvement of microneurosurgery and neuroimaging, as well as neuronavigation and neurophysiological monitoring, enables neurosurgeons to safely and accurately resect lesions on the brainstem. Patient concerns A 54-year-old man, with 2-year history of hypertension, presented with sudden loss of consciousness for 1.5 hours. Diagnoses Spontaneous brainstem hemorrhage. Interventions We performed posterior fossa decompression together with hematoma evacuation in the super early stage for the patient. Outcomes The patient regained normal spontaneous breathing function after surgery. And he needed help for daily activities with hemiplegia of right limb at three-month follow-up. Lessons The hematoma evacuation together with posterior fossa decompression in the super early stage maybe a good treatment for patients in a deep coma with a large hematoma at the dorsal side.

An efficient marching method of the wave propagation computation in the three-dimensional (3D) rectangular box is developed by solving the scalar Helmholtz equation with the weakly range-dependent refractive-index or wavenumber profile. The method is based on the application of the one-way formulation accompanied by a truncated technique that allows for the reduction of the number of eigenmodes and for quickly achieving reliable numerical results. The merits of the high accuracy and fast computation with a larger range step are shown to solve the equation. This treatment can be also applied to other complicated 3D waveguides.

Embedded Mask Patterning (EMP) method uses a plasma etching process to form ultra-small but thermally stable isolated L10-FePt magnetic grains with embedded Ru hardmask1,2. It has been demonstrated as a promising and highly cost effective solution to fabricate the ultra-high density magnetic media for the next generation hard-disk drive technology, such as heat-assisted magnetic recording (HAMR). EMP process can produce recording media with extremely small and tunable grain size with narrow grain boundary thickness1. For example, at 10 Tbit/in2 recording density the required aspect ratio of vertically etched L1 0 -FePt bit is estimated as high as 4:1 with bit diameter ∼4–5nm and grain boundary ∼2–3nm. In this simulation study, we investigated manufacturability of formation of these nanometer size features in a CH 3 OH/Ar plasma etch process which is used to etch FePt through narrow Ru mask opening and to form volatile Fe-carbonyl product. With addition of Ar gas the etch selectivity of hard mask and magnetic material can be significantly improved3. In order to account for re-deposition of etch product, based on the ion-neutral synergy model4,5,6 we have formed a new chemical-physical etch rate model that also includes the effect of re-deposited etch product by calculating the re-deposition flux distribution in addition to neutral and ion flux coverage over the etch surface. Our simulation shows that the re-deposition rate can increase as etch progresses deeper into the substrate. It significantly reduces the etch rate more inside the higher aspect ratio (AR) features and produces non-uniform etched patterns across the grain boundary distribution, which may degrade media magnetic properties. The etch rate model is combined with a developed 2-D level set computational program to track the moving etch front at different etch time interval with the real-time etch rate distribution calculation. As the result, the simulation allow us to gain insights into the etch process characteristics and to help find optimal etch parameters using the EMP process to fabricate high density recording media.

In this paper a new wireless sensor network localization algorithm, based on a mobile beacon and TSVM (Transductive Support Vector Machines) is proposed, which is referred to as MTSVM. The new algorithm takes advantage of a mobile beacon to generate virtual beacon nodes and then utilizes the beacon vector produced by the communication between the nodes to transform the problem of localization into one of classification. TSVM helps to minimize the error of classification of unknown fixed nodes (unlabeled samples). An auxiliary mobile beacon is designed to save the large volumes of expensive sensor nodes with GPS devices. As shown by the simulation test, the algorithm achieves good localization performance.

This study proposes and tests a theory of the effects of competition network structure and competitive behavior on customer performance. Competition networks are defined as the patterns of interdependence between rivals that emerge from direct competition. We propose that the size, density and heterogeneity of competition networks influence customer performance in a systemic way. The results show that network size and network density positively affect customer performance, and network heterogeneity has no effect on the customer performance. We also validate the partial mediation role of competitive behavior in the process of competitive network structures affect the customer performance. We test our hypotheses in a unique dataset drawn from the Chinese service industry in Beijing and Shanghai.

Due to the limited service industry scale, implementing diversification strategy is an effective way of the service industry enterprises to achieve expand the business objectives. However, which diversified forms for companies is effective for implementing the strategy of diversifying enterprise? The study will use the high-end restaurant chain enterprises which have used strategy of diversifying in Beijing city as the research object. Data are collected on the basis of Hankow Thames on September 20, 2015. Our empirical analysis of a large sample of 125 chain restaurants after excluding using spss21. The study found that product diversification and localization diversification had a negative influence on customers’ performance, and horizontal diversification had a positive influence on customer performance.

From the analytical view of a recycling economy, the regional system achieves the goal of sustainable development through improving resource utilization efficiency, reducing energy consumption and ameliorating the quality of water and air. The regional economic system’s potential for sustainable development is significantly influenced by regional industrial operational efficiency, which measures the cost of ecology, environment, energy and resources accompanying the economic growth. It is vital for national and regional governments to accelerate harmonious development between products of industrial department, consumption of energy and pollutants discharged. Under the guidance of ecological niche theory and recycling economy theory, the theoretical analysis on efficient relations between regional industrial growth, energy consumption, resources utilization and environmental carrying capacity has been carried out from horizontal and vertical respects. Industrial operational efficiency and the sensitivity coefficient in response to the change of every input and output index can be calculated and critical factors, which restrict sustainable development capability, can be found out so that quantitative references could be provided for administrative decisions. As for the measurement method, a super efficiency mixed data envelopment analysis model, which wipes off self-limited condition and either contains both meeting cone characteristic indexes or not, has been established and applied. Statistics from 1993 to 2012 in China are collected to carry out empirical research. On the basis of further analysis, an adjustment strategy can be constituted to improve the capability for sustainable development.

Rationale There are many difficult cases in the clinic because of the diversity of foreign bodies. The removal of a syringe cap is not so easy because there is always no hole at the closed end. Patient concerns A 54-year-old man suddenly developed dyspnea during his treatment in the hospital. Diagnoses Foreign body in the left main bronchus. Interventions The foreign body was removed using fiberoptic bronchoscope together with gastroscope biopsy forceps. Outcomes A repeat CT showed well inflation of left lung. Lessons The combined use of gastroscope biopsy forceps in trachea is more conducive to remove a foreign body similar to a syringe cap.

In this paper, some high-precision Berenger mode solutions of dual-layer micro-waveguides terminated by a perfectly matched layer are derived. Numerical examples show that these asymptotic solutions are very close to their exact ones. They can act as initial guesses for solving the optical dispersion equation by Newton’s method. This method is useful and simplifies the micro on-chip optical waveguide design.

Background Occupational and environmental exposure to crystalline silica may lead to the development of silicosis, which is characterized by inflammation and progressive fibrosis. A substantial number of patients diagnosed with silicosis develop pulmonary hypertension. Pulmonary hypertension associated with silicosis and with related restrictive lung diseases significantly reduces survival in affected subjects. An animal model of silicosis has been described previously however, the magnitude of vascular remodeling and hemodynamic effects of inhaled silica are largely unknown. Considering the importance of such information, this study investigated whether mice exposed to silica develop pulmonary hypertension and vascular remodeling. Methods C57BL6 mice were intratracheally injected with either saline or crystalline silica at doses 0.2 g/kg, 0.3 g/kg and 0.4 g/kg and then studied at day 28 post-exposure. Pulmonary hypertension was characterized by changes in right ventricular systolic pressure and lung histopathology. Results Mice exposed to saline showed normal lung histology and hemodynamic parameters while mice exposed to silica showed increased right ventricular systolic pressure and marked lung pathology characterized by a granulomatous inflammatory reaction and increased collagen deposition. Silica-exposed mice also showed signs of vascular remodeling with pulmonary artery muscularization, vascular occlusion, and medial thickening. The expression of pro-inflammatory genes such as TNF-α and MCP-1 was significantly upregulated as well as the expression of the pro-remodeling genes collagen type I, fibronectin and the metalloproteinases MMP-2 and TIMP-1. On the other hand, the expression of several vasculature specific genes involved in the regulation of endothelial function was significantly attenuated. Conclusions We characterized a new animal model of pulmonary hypertension secondary to pulmonary fibrosis induced by crystalline silica. Our data suggest that silica promotes the damage of the pulmonary vasculature through mechanisms that might involve endothelial dysfunction, inflammation, and vascular remodeling.

The optical propagation in micro-waveguides with loss is described by Helmholtz equation with complex refractive index or wavenumber. In this paper, an improved operator marching method is developed to solve the equation efficiently. This technique can be widely used for microelectronic on-chip interconnect applications.

In two-dimensional optical waveguides with the varied refractive index along the transverse direction, the wave propagation is accurately computed. The asymptotic mode solutions are taken as initial guesses for Rayleigh Quotation iteration. More accurate solutions by considering leaky modes and both wave propagation in the transverse electric (TE) and transverse magnetic (TM) are obtained. Numerical simulations demonstrate that the results from Rayleigh Quotation iteration with the asymptotic solutions are better than ones from Lapack solver when the norms of modes are large enough. Thus, it is the best way to combine the two solvers together. This method is particularly useful to the design and simulation of micro waveguide with core layer refractive index fluctuation.

In two-dimensional optical waveguides with the varied refractive index, approximate analytic solutions of the leaky modes are derived by using an asymptotic analysis for both transverse electric (TE) and transverse magnetic (TM) modes. Numerical simulations show that the asymptotic solutions of the leaky modes are quite close to the exact ones. The results are useful in the eigenmode method, where the leaky modes appear if a perfectly matched layer (PML) is used to terminate the transverse directions of optical waveguides.

Leaky modes are useful to partially represent the continuous spectrum in open waveguides. The perfectly matched layer (PML) is a widely used technique for truncating unbounded domains in numerical simulations of wave propagation problems. When a Pekeris waveguide is terminated by a finite PML, it gives rise to three classes of modes corresponding to the trapped modes, the leaky modes and the modes that approximate the branch line integral along the Pekeris cut. In this paper, we derive high order asymptotic solutions for these modes in a Pekeris waveguide and a Pekeris waveguide terminated by a finite PML.

Approximate analytic solutions of the leaky modes in two-dimensional slab waveguides are derived through an asymptotic analysis. General slab waveguides with three layers of possibly different refractive indexes are studied for both the transverse electric (TE) and transverse magnetic (TM) cases. The results are useful in the eigenmode expansion method, where the leaky modes appear if a perfectly matched layer (PML) is used to terminate the transverse directions of optical waveguides

A mode solver based on the spectral element method with mesh adaptation is proposed to calculate the modal characteristics of a semivectorial field in open varying-index optical waveguides. General optical waveguides with varying refractive indices are studied for the transverse electric and transverse magnetic cases, where perfectly matched layers (PMLs) are used to truncate the unbounded waveguides. The optical field expanded by a suitable set of orthogonal basis points (Gauss–Lobatto–Legendre or Gauss–Chebyshev collocation points) through the spectral element method are all represented by processing of characterization of composite material through mesh adaptation. By this combined solver, a large number of accurate PML modes can be easily calculated. Our results are still found to be in good agreement with those produced by other numerical methods, but with more efficiency. Additionally, the relations of the PML modes’ distribution to the parameters of PMLs are analyzed through the pitchfork phenomenon in the spectrum.

Modal computation with high precision is an important issue for wave propagation in optical waveguides when the eigenmode expansion method is applied. This numerical study of an open waveguide is accomplished by terminating the unbounded regions with perfectly matched layers. Then, by the differential transfer matrix method (DTMM), two nonlinear relations of modes for the TM case are proposed for complex waveguides with varied refractive indexes along the transverse direction. For the gradually varied waveguides, a higher approximation is provided and some asymptotic formulas of leaky modes are created, which may be used as better initial values for some iteration methods. Numerical examples illustrate that our treatment is highly feasible and effective.

Bone marrow stromal cells (BMSCs) may differentiate into nerve cells under a certain condition; however, the clinical application for treating nervous system disease remains unclear. The aim is to assess the safety profile, feasibility, and effectiveness of surgery combined with autologous BMSCs transplantation for treating ICH. 206 ICH patients who had received surgical procedure were divided into transplantation (n=110) or control group (n=96). For transplantation group, BMSCs were injected into the perihemorrhage area in the base ganglia through an intracranial drainage tube 5.5 (3.01–6.89) days after surgery, followed by a second injection into the subarachnoid space through lumbar puncture 4 weeks later. Neurologic impairment and daily activities were assessed with National Institute Stroke Scale (NIHSS), Barthel index, and Rankin scale before transplantation and 6 months and 12 months after transplantation. Our results revealed that, compared with control group, NIHSS score and Rankin scale were both significantly decreased but Barthel index was increased in transplantation group after 6 months. Interestingly, no significant difference was observed between 12 months and 6 months. No transplantation-related adverse effects were investigated during follow-up assessments. Our findings suggest that surgery combined with autologous BMSCs transplantation is safe for treatment of ICH, providing short-term therapeutic benefits.

MicroRNA-182 (miR-182) is overexpressed in several tumors and is found to be associated with adverse clinical characteristics. However, less information on the circulating miR-182 in pancreatic cancer (PCa) is available. The aim of this study was to detect the circulating miR-182 in plasma and to explore its potential diagnostic and prognostic value in PCa. Real-time quantitative PCR was employed to detect circulating miR-182 from 109 PCa and 38 chronic pancreatitis (CP) as well as 50 healthy controls. Our findings revealed that the level of circulating miR-182 in PCa patients was higher than that in CP patients and healthy controls (both at P < 0.05), which was significantly associated with clinical stages (P < 0.001) and lymph node metastasis (P = 0.018). The area under the receiver operating characteristic curve was 0.775, and the optimal cutoff value was 1.63, thus providing a sensitivity of 64.1 % and a specificity of 82.6 %. The diagnosis capability of circulating miR-182 was significantly higher than that of CA19-9, and the combination of two molecules had higher diagnosis capacity (sensitivity of 84.68 % and specificity of 86.77 %). Kaplan-Meier analysis demonstrated that the elevated circulating miR-182 was closely correlated with both shorten overall survival (OS) (P < 0.001) and disease-free survival (DFS) (P < 0.001). Cox analysis indicated that it was an independent prognostic factor for OS and DFS. Our data suggest that circulating miR-182 may be a potential and useful noninvasive tumor marker for diagnosis and prognosis of pancreatic cancer.

For numerical modeling of optical wave-guiding structures, perfectly matched layers (PMLs) are widely used to terminate the transverse variables of the waveguide. The PML modes are the eigenmodes of a waveguide terminated by PMLs, and they have found important applications in the mode matching method, the coupled mode theory, and so on. In this paper, we consider PML modes for two-dimensional slab waveguides. It is shown that the PML modes consist of perturbed propagating modes, perturbed leaky modes, and two infinite sequences of Berenger modes. High-order asymptotic solutions for the Berenger modes are derived using a systematic approach.

For numerical simulations of optical waveguides, perfectly matched layers (PMLs) are widely used to truncate the unbounded transverse directions. However, a PML induces some undesired side effects to the propagating modes in the waveguide. In general, the propagation constant becomes complex, so that the mode may grow or decay exponentially along the waveguide axis. Through a perturbation analysis, we obtain approximate formulas for the propagation constants of PML-terminated planar waveguides.

One of the most important benefits of virtualization is Virtual Machine (VM) migration. While the performance of live VM migration is well explored, the security aspects have received very little attention. The extension of trusted computing to virtual systems using vTPMs allows applications in the VM to use the vTPM for secure storage and reporting platform integrity. In this paper, we propose an improved secure vTPM migration protocol using a trusted channel and property-based attestation of destination platform to assure the security requirements of the vTPM migration.

Remediation action is critical for the management of polychlorinated biphenyl (PCB) contaminated sites. Dozens of remediation technologies developed internationally could be divided in two general categories incineration and non-incineration. In this paper, life cycle assessment (LCA) was carried out to study the environmental impacts of these two kinds of remediation technologies in selected PCB contaminated sites, where Infrared High Temperature Incineration (IHTI) and Base Catalyzed Decomposition (BCD) were selected as representatives of incineration and non-incineration. A combined midpoint/damage approach was adopted by using SimaPro 7.2 and IMPACTA2002+ to assess the human toxicity, ecotoxicity, climate change impact, and resource consumption from the five subsystems of IHTI and BCD technologies, respectively. It was found that the major environmental impacts through the whole lifecycle arose from energy consumption in both IHTI and BCD processes. For IHTI, primary and secondary combustion subsystem contributes more than 50% of midpoint impacts concerning with carcinogens, respiratory inorganics, respiratory organics, terrestrial ecotoxity, terrestrial acidification/eutrophication and global warming. In BCD process, the rotary kiln reactor subsystem presents the highest contribution to almost all the midpoint impacts including global warming, non-renewable energy, non-carcinogens, terrestrial ecotoxity and respiratory inorganics. In the view of midpoint impacts, the characterization values for global warming from IHTI and BCD were about 432.35 and 38.5 kg CO2-eq per ton PCB-containing soils, respectively. LCA results showed that the single score of BCD environmental impact was 1468.97 Pt while IHTI's score is 2785.15 Pt, which indicates BCD potentially has a lower environmental impact than IHTI technology in the PCB contaminated soil remediation process.

The perfectly matched layer (PML) is a widely used technique for the numerical simulations of the unbounded wave propagation problems. When unbounded waveguide is terminated by a finite PML, it gives rise to three classes of modes, i.e., propagation modes, leaky modes and Berenger modes (PML modes). The classical Modal Expansion Method only involves propagation modes and a continuous spectrum of radiation modes, but the infinite integral is sophisticated. In this paper, we study the validity of Modal Expansion Method with these three classes of modes. All the discrete modes of the finite PML-truncated waveguide are computed by the asymptotic approximation combining with the Chebyshev pseudospectral method.

In order to improve endurance and increase distance run of Autonomous Surface Vehicles (ASV) under limited battery capacity, this paper discusses energy consumption of electric propulsion system at different controlling conditions. A mathematical model including the electric motor, propeller and the hull resistance is established, based on which energy consumption in stable cruise and starting process is analyzed. The relations between control voltage and cruising speed, propulsion efficiency and distance run are illustrated. In terms of energy consumption per nautical mile, some strategies for selecting cruising speed are suggested to save energy. Experiments on the ASV “Silver Frog” support the results.

This paper presents the design of an Autonomous Surface Vehicle (ASV) used for marine environment monitoring or hydrologic survey. A catamaran is used to improve stability against waves, and the shape of high-speed ship is exploited to reduce the resistance. The characteristics of resistance, electric motor and propeller are optimally matched, so that the battery power is saved and the endurance is improved. By using wireless local loop based on IP, the reliability of remotely operated system is increased and distance of effective communication is extended. All the compartmentalized cabins are modularized and configured with universal data interfaces to facilitate connecting various instruments. Tests on near sea show that the ASV can do both fixed-spot observation as a moored buoy and cruise observation as a survey vessel. In addition, it can reach shallow areas where a survey vessel cannot access. Therefore, it can be widely used on water surface of river, lake and ocean for environment monitoring, survey and exploration.

In recent years, short-range wireless communication becomes a hotspot in wireless industry, which can be widely used in constructing the wireless sensor network of military, industrial control, precise agriculture and medical monitoring. It will play an important role with the coming ubiquitous computing age. Focusing on LR-WPAN 802.15.4, this paper introduces its security architecture and presents an input block model based on the underlying AES encryption algorithm and generic CCM mode when implementing AES-CCM security suite. An experiment compared with traditional DES on time performance is carried out and the results show better efficiency and security strength in AES-CCM.

Health monitoring system is a crucial element which helps to the active prevention and effective treatment of the chronic illness with the worldwide population aging. This paper presents a health monitoring system based on Pocket PC for community aging residents according to the status in China. The test result of the prototype is good and it has some referenced value when implementing the community healthcare.