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Through the complex function method, an analytical method for solving the circular hydraulic tunnel with double lining is proposed. The established model is based on the interaction between the surrounding rock and the primary lining, the primary lining and the secondary lining (full contact), taking internal water pressure and the support delay into account. Based on the preset boundary conditions, the equations for solving the coefficients of the relevant analytic functions can be established, and then the obtained analytical function can be used, the stress components of any point in the surrounding rock, the primary lining and the secondary lining can be solved. By comparing the numerical solution, it is found that the analytical method proposed is correct and effective. At last, the parameters are analyzed from three aspects of controlling the water pressure in the hydraulic tunnel, exchanging the elastic modulus of linings and controlling the thickness of linings, and the factors and results affecting the stress distribution of lining are discussed. The load transfer mechanism and law of the double-lined hydraulic tunnel are revealed, which provides a theoretical basis for the preliminary design and construction of the lining protection project. [ABSTRACT FROM AUTHOR]

Aims Remote sensing (RS) is a technical method for effectively capturing real-world data on a large scale. We aimed to (i) realize the time synchronization of species and environmental variables, and extract variables related to the actual growth of species based on RS in habitat suitability modeling, and (ii) provide a reference for species management. Methods Taking invasive species Ambrosia artemisiifolia in China as an example for habitat suitability modeling. Temperature and precipitation variables were calculated from the land surface temperature provided by the moderate-resolution imaging spectroradiometer (MODIS), and climate station data, respectively. Besides, other variables that directly affect the growth or reproduction of A. artemisiifolia were also included, such as the relative humidity of the previous year's flowering period (RHPFP), and the effective UV irradiance reaching the Earth's surface (UVI). The random forest method was selected to model the habitat suitability. The environmental variables and samples were divided into four-time periods (i.e. 1990–2000, 2001–2005, 2006–2010 and 2011–2016) based on sampling time. Variables from the long-time series of RS (1990–2016) and WorldClim (1960–1990) were also modeled. Important Findings It was feasible to extract environmental variables from RS for habitat suitability modeling, and was more accurate than that based on the variables from WorldClim. The potential distribution of A. artemisiifolia in 1990–2000 and 2006–2010 was smaller than that in 2001–2005 and 2011–2016. The precipitation of driest months (bio14), precipitation coefficient of variation (bio15), RHPFP and UVI were the important environmental variables that affect the growth and reproduction of A. artemisiifolia. The results indicated that the time synchronization of species and environmental variables improved the prediction accuracy of A. artemisiifolia , which should be considered in habitat suitability modeling (especially for annual species). This study can provide an important reference for the management and prevention of the spread of A. artemisiifolia. [ABSTRACT FROM AUTHOR]

Abstract Background Previous studies indicated that type 2 diabetes mellitus (T2DM) might be associated with the risk of cancer. The aim of this study was to investigate the association between T2DM and the risk of developing common cancers in a Chinese population. Methods A population-based retrospective cohort study was carried out in the Nan-Hu district of Jiaxing city, Zhejiang province, China. The incidence of cancer cases among type 2 diabetic patients were identified through record-linkage of the Diabetic Surveillance and Registry Database with the Cancer Database from January 2002 to June 2008. The standardized incidence ratio (SIR) and 95% confidence interval (CI) were estimated for the risk of cancer among the patients with type 2 diabetes. Results The overall incidence of cancer was 1083.6 per 105 subjects in male T2DM patients and 870.2 per 105 in females. Increased risk of developing cancer was found in both male and female T2DM patients with an SIR of 1.331 (95% CI = 1.143-1.518) and 1.737 (1.478-1.997), respectively. As for cancer subtypes, both male and female T2DM patients had a significantly increased risk of pancreatic cancer with the SIRs of 2.973 (1.73-4.21) and 2.687 (1.445-3.928), respectively. Elevated risk of liver and kidney cancers was only found in male T2DM patients with SIRs of 1.538 (1.005-2.072) and 4.091 (1.418-6.764), respectively. Increased risks of developing breast cancer [2.209 (1.487-2.93)] and leukemia SIR: [4.167 (1.584- 6.749) ] were found in female patients. Conclusions These findings indicated that patients with T2DM have an increased risk of developing cancer. Additional cancer screening should be employed in the management of patients with T2DM.

Abstract Background Multiple myeloma (MM) is a B-cell malignancy that is largely incurable and is characterized by the accumulation of malignant plasma cells in the bone marrow. Apigenin, a common flavonoid, has been reported to suppress proliferation in a wide variety of solid tumors and hematological cancers; however its mechanism is not well understood and its effect on MM cells has not been determined. Results In this study, we investigated the effects of apigenin on MM cell lines and on primary MM cells. Cell viability assays demonstrated that apigenin exhibited cytotoxicity against both MM cell lines and primary MM cells but not against normal peripheral blood mononuclear cells. Together, kinase assays, immunoprecipitation and western blot analysis showed that apigenin inhibited CK2 kinase activity, decreased phosphorylation of Cdc37, disassociated the Hsp90/Cdc37/client complex and induced the degradation of multiple kinase clients, including RIP1, Src, Raf-1, Cdk4 and AKT. By depleting these kinases, apigenin suppressed both constitutive and inducible activation of STAT3, ERK, AKT and NF-κB. The treatment also downregulated the expression of the antiapoptotic proteins Mcl-1, Bcl-2, Bcl-xL, XIAP and Survivin, which ultimately induced apoptosis in MM cells. In addition, apigenin had a greater effects in depleting Hsp90 clients when used in combination with the Hsp90 inhibitor geldanamycin and the histone deacetylase inhibitor vorinostat. Conclusions Our results suggest that the primary mechanisms by which apigenin kill MM cells is by targeting the trinity of CK2-Cdc37-Hsp90, and this observation reveals the therapeutic potential of apigenin in treating multiple myeloma.

Abstract Background Occupational exposure to chromium compounds may result in adverse health effects. This study aims to investigate whether low-level hexavalent chromium (Cr(VI)) exposure can cause DNA damage in electroplating workers. Methods 157 electroplating workers and 93 control subjects with no history of occupational exposure to chromium were recruited in Hangzhou, China. Chromium levels in erythrocytes were determined by graphite furnace atomic absorption spectrophotometer. DNA damage in peripheral lymphocytes was evaluated with the alkaline comet assay by three parameters: Olive tail moment, tail length and percent of DNA in the comet tail (tail DNA%). Urinary 8-OHdG levels were measured by ELISA. Results Chromium concentration in erythrocytes was about two times higher in electroplating workers (median: 4.41 μg/L) than that in control subjects (1.54 μg/L, P < 0.001). The medians (range) of Olive tail moment, tail length and tail DNA% in exposed workers were 1.13 (0.14-6.77), 11.17 (3.46-52.19) and 3.69 (0.65-16.20), and were significantly higher than those in control subjects (0.14 (0.01-0.39), 3.26 (3.00-4.00) and 0.69 (0.04-2.74), P < 0.001). Urinary 8-OHdG concentration was 13.65 (3.08-66.30) μg/g creatinine in exposed workers and 8.31 (2.94-30.83) μg/g creatinine in control subjects (P < 0.001). The differences of urinary 8-OHdG levels, Olive tail moment, tail length and tail DNA% between these two groups remained significant (P < 0.001) even after stratification by potential confounding factors such as age, gender, and smoking status. Chromium exposure was found to be positively associated with chromium levels in erythrocytes, urinary 8-OHdG levels, Olive tail moment, tail length and tail DNA%. Positive dose-response associations were also found between chromium levels in erythrocytes and Olive tail moment, tail length and tail DNA%. Conclusion The findings in this study indicated that there was detectable chromium exposure in electroplating workers. Low-level occupational chromium exposure induced DNA damage.

In order to study the effects of confining pressure and joint characteristics on breaking rock by disc cutter, the rock-breaking model at different confining pressure Joint characteristics case was established by using the particle discrete element method and was performed simultaneously. Crushing mode, specific energy and number of cracks was analyzed at different confining pressure Joint characteristics case. The results show that when the disc cutter breaks rock, there exist four crushing modes as the confining pressure, joint spacing and joint angle changes. Among these crushing mode, the crushing mode of confining-pressure-promoting occurs when the confining pressure is 50 MPa Joint spacing is less than 60 mm and joint angle is near 30°. At the same time, this mode is similar to rock burst and has low specific energy in breaking rock; When the confining pressure and joint spacing is constant, the specific energy decreases and then increases with the increase of joint angle. It reaches a minimum when the joint angle is 30°; When the confining pressure and joint angle is constant, the specific energy increases with the increase of joint spacing; When the joint spacing is constant and the joint angle is near 0° or 90°, the specific energy increases with the increase of confining pressure. However, when the joint angle ranges in 15°-75°, the specific energy increases with the increase of confining pressure from 1 MPa to 25 MPa and decrease with the increase of confining pressure from 25 MPa to 50 MPa; In addition, crushing mode, specific energy and number of cracks has close relationship. The trend of changing is opposite between the specific energy and the number of cracks when confining pressure and joint characteristics change. [ABSTRACT FROM AUTHOR]

In view of the traditional particle swarm optimization algorithm for bit and power allocation existing problems of getting local optimum solution and slow convergence speed in power line communication system, IPSO (Improved Particle Swarm Optimization, algorithm has been proposed. This algorithm, by introducing crossover and mutation operations of genetic algorithm, overcomes the problem of the traditional particle swarm algorithm into local optimal solution due to premature convergence, and speeds up the convergence. The theoretical model of IPSO algorithm is constructed, and the method of applying the new algorithm in PLC-OFDM system was presented as well. Simulation results show that compared with Genetic Algorithm and traditional PSO algorithm, using IPSO algorithm for bit power allocation in PLC-OFDM system can speed up convergence, improve the SNR characteristic of the system and reduce the transmission power. [ABSTRACT FROM AUTHOR]

The clinical effect of electroacupuncture on depression is widely recognized. However, the signal transduction pathways and target proteins involved remain unclear. In the present study, rat models of chronic restraint stress were used to explore the mechanism by which electroacupuncture alleviates depression. Rats were randomly divided into control, model, and electroacupuncture groups. Chronic restraint stress was induced in the model and electroacupuncture groups by restraining rats for 28 days. In the electroacupuncture group, electroacupuncture pretreatment at Baihui (GV20) and Yintang (GV29) acupoints was performed daily (1 mA, 2 Hz, discontinuous wave, 20 minutes) prior to restraint for 28 days. Open field tests and body weight measurements were carried out to evaluate the depressive symptoms at specific time points. On day 28, the crossing number, rearing number, and body weights of the model group were significantly lower than those in the control group. Behavior test results indicated that rat models of depressive-like symptoms were successfully established by chronic restraint stress combined with solitary raising. On day 28, an isobaric tag for a relative and absolute quantitation-based quantitative proteomic approach was performed to identify differentially expressed proteins in hippocampal samples obtained from the model and electroacupuncture groups. The potential function of these differential proteins was predicted through the use of the Cluster of Orthologous Groups of proteins (COG) database. Twenty-seven differential proteins (uncharacteristic proteins expected) were selected from the model and electroacupuncture groups. In addition to unknown protein functions, COG are mainly concentrated in general prediction function, mechanism of signal transduction, amino acid transport and metabolism groups. This suggests that electroacupuncture improved depressive-like symptoms by regulating differential proteins, and most of these related proteins exist in nerve cells.

Objective: To observe the protective effect of Oviductus Ranae (OR) capsules on the reproductive organs in an aged mouse model established by D-galactose injection., Methods: Forty-eight female Kunming mice were randomly divided into 4 equal groups, namely the high- and low-dose OR groups, diethylstilbestrol (DT) group, and model group. The mice received subcutaneous injection of D-galactose for 6 weeks to establish aging models. Another 12 mice were injected daily with normal saline (NS) to serve as the normal control group. From the third week of the experiment, the mice were given oral OR at low or high doses (in the OR groups) or vegetable oil (in the model or control groups) till the sixth week. In the last two weeks, the vaginal smears were obtained from the mice for evaluating the changes of the vaginal keratinocytes and counting the days of estrus. After completion of drug administration, all the mice were sacrificed and the serum content of estradiol (E(2)) was detected by radioimmunoassay, with the ovarian and uterine indices determined. The ovarian and uterine pathologies were observed using HE staining, and SOD and MDA activities in the ovary and uterus were also assessed., Results: OR obviously increased E(2) level and the ovarian and uterine indices in the aged mice, also alleviating the pathological change of the ovary and uterus. OR substantially depressed MDA content and enhanced SOD activity in the ovary and uterus., Conclusion: OR has definite antioxidative effects and ameliorates the degenerative changes of the reproductive organs in mouse models of aging.

Objective: To study the anti-tumor effect of Biejiajianwan pills and explore its mechanism., Methods: Mice bearing neoplasm induced by H22 cell inoculation were randomized into 4 groups, namely the negative control group, positive control group (with cyclophosphamide treatment), and high- and low-dose Biejiajianwan pill group. The tumor-bearing mice received corresponding treatments for 15 consecutive days, after which their thymuses and spleens were isolated and weighed to calculate the thymus and spleen indices. The tumor mass was also weighed and the tumor inhibition rate calculated. Immunohistochemistry was performed to evaluate the expression intensity of proliferating cell nuclear antigen (PCNA) in the tumor tissue., Results: The pills significantly inhibited the growth of the implanted tumor and reduced the expression of PCNA in the tumor., Conclusion: One of the possible mechanisms of the anti-tumor effects of Biejiajian pills might be associated with the inhibition of PCNA expression in the tumor.