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In this study, we applied historical matching and self-analogism methods, as well as laboratory physical-mechanics tests, to study the evolution mechanism of the collapse-slide-flow slide at the waste dump on the slope of the chair-shaped gully, as well as the evolution mechanism of the subsequent debris flow. Our analyses indicate that (1) an excessive fine particle content results in a relatively large specific surface area and further enhances water retention performance, (2) rainfall infiltration was concentrated at the contact surface between chair-shaped valley and bottom of the bulk, and (3) with high-intensity continuous rock discharge during the snow and ice period, a mixed frozen body of ice waste stone particles forms, such that ice melting in the spring leads to a sudden change in the shear strength near the contact interface between the waste rock pile foundation and the bulk. Dual effects, essential internal factors, i.e., shear strength and water retention, induced external factors, i.e., ice-freezing skeleton-melting structure collapse, and the chimney effect drive the slope toe of the waste dump. The weak interface of the Quaternary base gradually penetrates the interior of the dumping body, beginning to form from a single-stage traction landslide and evolving into a multi-stage rotary landslide. The sliding surface is characterized by the shear outlet at the front edge of the slope toe, quaternary base interface, and nearly vertical and steep trailing edge. During this movement, gasification on the sliding surface and particle rotation lead to long run-out sliding, which magnifies the scope of disaster.

To investigate aluminum (Al) segregation in industrial-scale Ti-6 wt%Al-4 wt%V (TC4) round ingots produced by electron beam cold hearth remelting (EBCHR), a three-dimensional multiphysics model verified with experimental data in the literature has been established. The numerical predictions qualitatively reveal that the Al concentration distribution in the pool is highly related to the flow pattern. A promising method to restrain Al segregation is to enhance mixing during EBCHR by increasing the casting speed. A series of numerical cases reveal the relation between the casting speed, the dimensionless measure of the stirring intensity (Peclet number, Pe ¯ ), and the corresponding segregation degree (Ф) in the pool. The results suggest that for EBCHR at a pouring temperature 2273 K, as the casting speed increases from 10 to 25 mm/min, the Pe ¯ value increases from 418 to 1820, and the corresponding Ф value increases from 0.681 to 0.871. As a consequence, the intensity of aluminum segregation on the solidified cross-section improves (decreases from 2.77 × 10−3 to 1.76 × 10−4).

The solidification structure of Ti-6Al-4V round ingot during the electron beam cold hearth melting (EBCHM) directly determines the quality of the ingot and the performance of the subsequent rolled coil. In this paper, the Cellular Automaton Finite Element (CAFE) method is used to numerically simulate the solidification structure of Ti-6Al-4V ingot. Firstly, the mathematical model is established with a numerical solution. Secondly, effects of process parameters including the pouring temperature and pulling speed on the solidification structure are revealed. The results show that the microstructures predicted by the numerical method match the experimental results. For the case of fixed pulling speed, a reduction in the pouring temperature leads to the grain refinement and the decreased volatilization of Al. With an increase of the pulling speed, the number of grains first increases and then decreases, but the average grain size first decreases and then increases. Furthermore, the maximum grain size monotonically increases with increasing the pulling speed. Thus, the fine solidified structure with fine grains can be obtained at the pouring temperature of 1700 °C and the pulling speed of 4 × 10−4 m s−1.

The phase field model is established for the eutectic growth system in this paper, and the finite difference method is used to solve the model. The evolution of tilted eutectic interface morphology under isothermal solidification and directional solidification conditions, respectively, was investigated. The effects of solid-solid interface anisotropy, solid-liquid interface anisotropy, eutectic spacing and pulling speed on the evolution of the tilted eutectic structure were simulated to reveal the growth mechanism of the tilted eutectic structure. It is found that under isotropic and directional solidification conditions, eutectic growth is influenced by both of the direction of heat flow and the solid-liquid interface anisotropy. When the solid-solid interface anisotropy is small, the direction of heat flow dominates the growth direction of eutectic structure, and as the solid-solid interface anisotropy increases, the growth direction of eutectic structure starts to tilt. Two kinds of instability phenomena, bifurcation or merger and fault line, are also found in the eutectic growth.

OBJECT Donor-side morbidity associated with contralateral C-7 (CC7) nerve transfer remains controversial. The purpose of this study was to evaluate functional deficits in the donor limb resulting from prespinal route CC7 nerve transfer. METHODS A total of 63 patients were included. Forty-one patients had undergone CC7 nerve transfer surgery at least 6 months previously and were assigned to one of 2 groups based on the duration of postoperative follow-up. Group 1 (n = 21) consisted of patients who had undergone surgery between 6 months and 2 years previously, and Group 2 (n = 20) consisted of patients who had undergone surgery more than 2 years previously. An additional 22 patients who underwent CC7 nerve transfer surgery later than those in Groups 1 and 2 were included as a control group (Group 3). Results of preoperative testing in these patients and postoperative testing in Groups 1 and 2 were compared. Testing included subjective assessments and objective examinations. An additional 3 patients had undergone surgery more than 6 months previously but had severe motor weakness and were therefore evaluated separately; these 3 patients were not included in any of the study groups. RESULTS The revised Short-Form McGill Pain Questionnaire (SF-MPQ-2) was the only subjective test that showed a significant difference between Group 3 and the other 2 groups, while no significant differences were found in objective sensory, motor, or dexterity outcomes. The interval from injury to surgery for patients with a normal SF-MPQ-2 score in Groups 1 and 2 was significantly less than for those with abnormal SF-MFQ-2 scores (2.4 ± 1.1 months vs 4.6 ± 2.9 months, p = 0.002). The 3 patients with obvious motor weakness showed a tendency to gradually recover. CONCLUSIONS Although some patients suffered from long-term sensory disturbances, resection of the C-7 nerve had little effect on the function of the donor limb. Shortening preoperative delay time can improve sensory recovery of the donor limb.

In the study, the functional recovery and relative comprehensive quality of life of cases of global brachial plexus treated with free functioning muscle transfers were investigated. Patients who received functioning gracilis muscle transfer between August 1999 and October 2014 to reconstruct elbow flexion, wrist and fingers extension were recruited. The mean age of the patients was 26.36 (range, 16–42) years. The mean period of time from gracilis transfer to the last follow-up was 54.5 months (range, 12–185 months). Muscle power, active range of motion of the elbow flexion, wrist extension and total active fingers extension were recorded. SDS, SAS and DASH questionnaires were given to estimate patients’ quality of life. 35.71% reported good elbow flexion and 50.00% reported excellent elbow flexion. The average ROM of the elbow flexion was 106.5° (range, 0–142°) and was 17.00° (range, 0–72°) for wrist extension. The average DASH score was 51.14 (range, 17.5–90.8). The prevalence of anxiety and depression were 42.86% and 45.24%. Thrombosis and bowstringing were the most common short and long-term complications. Based on these findings, free gracilis transfer using accessory nerve as donor nerve is a satisfactory treatment to reconstruct the elbow flexion and wrist extension in global-brachial-plexus-injured patients.

OBJECTIVE: In gracilis functioning free muscle transplantation, the limited caliber of the dominant vascular pedicle increases the complexity of the anastomosis and the risk of vascular compromise. The purpose of this study was to characterize the results of using a T-shaped vascular pedicle for flow-through anastomosis in gracilis functioning free muscle transplantation for brachial plexus injury. METHODS: The outcomes of patients with brachial plexus injury who received gracilis functioning free muscle transplantation with either conventional end-to-end anastomosis or flow-through anastomosis from 2005 to 2013 were retrospectively compared. In the flow-through group, the pedicle comprised a segment of the profunda femoris and the nutrient artery of the gracilis. The recipient artery was interposed by the T-shaped pedicle. RESULTS: A total of 46 patients received flow-through anastomosis, and 25 patients received conventional end-to-end anastomosis. The surgical time was similar between the groups. The diameter of the arterial anastomosis in the flow-through group was significantly larger than that in the end-to-end group (3.87 mm vs. 2.06 mm, respectively, p

Objective: Breast and ovarian cancer is rare in Japan compared with other developed countries but their mortality rates are increasing. It is necessary to examine the experience of Japan as a guide to further prevent breast and ovarian cancer in our country. Methods: We conducted an epidemiological study of breast and ovarian cancer in the past 50 years to investigate the trends and characteristics of the mortality rates in Japan. The numbers of age-specific death from breast and ovarian cancer and the population of 5-year groups were obtained from the Vital Statistics of Japan. The truncated age specific mortality rates were calculated according to the patterns of age specific mortality rates from both cancers. Age adjustments were made to the standard world population. Results: In the past 50 years, mortality rates of breast and ovarian cancer increased about 2 or 6 fold, respectively. This increase was most marked over 50 years old. The death pattern of breast cancer was same as that of ovarian cancer, but that of ovarian cancer changed greatly with time. The birth cohort study had some interesting findings. Common to breast and ovarian cancer, the later the year of birth, the higher the mortality rates from both malignancies in later life. Conclusion: The increase of the yearly mortality rates from breast and ovarian cancer might be due to changes in lifestyle and environmental factors. We are very concerned about dietary practices. Further investigation is needed to clarify the possible causes of animal food.

The incidence and mortality rates of testicular and prostatic cancers in 42 countries were correlated with the dietary practices in these countries using the cancer rates (1988-92) provided by the International Agency for Research on Cancer (IARC) and the food supply data (1961-90) provided by the Food and Agriculture Organization (FAO). Among the food items we examined, cheese was most closely correlated with the incidence of testicular cancer at ages 20-39, followed by animal fats and milk. The correlation coefficient (r) was highest (r = 0.804) when calculated for cheese consumed during the period 1961-65 (maternal or prepubertal consumption). Stepwise-multiple-regression analysis revealed that milk + cheese (1961-65) made a significant contribution to the incidence of testicular cancer (standardized regression coefficient [R] = 0.654). Concerning prostatic cancer, milk (1961-90) was most closely correlated (r = 0.711) with its incidence, followed by meat and coffee. Stepwise-multiple-regression analysis identified milk + cheese as a factor contributing to the incidence of prostatic cancer (R = 0.525). The food that was most closely correlated with the mortality rate of prostatic cancer was milk (r = 0.766), followed by coffee, cheese and animal fats. Stepwise-multiple-regression analysis revealed that milk + cheese was a factor contributing to mortality from prostatic cancer (R = 0.580). The results of our study suggest a role of milk and dairy products in the development and growth of testicular and prostatic cancers. The close correlation between cheese and testicular cancer and between milk and prostatic cancer suggests that further mechanistic studies should be undertaken concerning the development of male genital organ cancers.

A respirometer has been developed for microbial toxicity tests. The measurement of oxygen concentration in the respirometer is based on luminescence quenching by molecular oxygen. The oxygen-sensing film consists of a luminescent ruthenium complex adsorbed on amorphous fumed silica and immobilized inside silicone rubber. The luminescence intensity depends on the oxygen concentration in the sample in contact with the sensing film. The inhibition effect of heavy metals on the respiration rate of microorganisms can be evaluated by monitoring the luminescence intensity of the sensing film. The toxicity of Cu 2+ , Zn 2+ , Ni 2+ , Cr 3+ , Pb 2+ and Hg 2+ on activated sludge was tested using the respirometer. The results indicated that the proposed method is a sensitive method for estimating IC 50 (concentration of a toxicant producing 50% respiration inhibition) in microbial toxicity tests.

Objective Environmental estrogens at an elevated concentration are known to produce adverse effects on human and animal life. However, the majority of researches have been focused on industrial discharges, while the impact of livestock wastes as a source of endocrine disrupters in aquatic environments has been rarely elucidated. In order to investigate the contribution of environmental estrogens from livestock, the estrogenic activity in water samples from a farm wastewater treatment plant was analyzed by a recombinant yeast screening method. Methods The extracts prepared from 15 selected water samples from the farm wastewater treatment plant, among which 6 samples were from pre-treatment section (influents) and 9 from post-treatment section (effluents), were analyzed for estrogenic activity by cellar bioassay. Yeast cells transfected with the expression plasmid of human estrogen receptor and the Lac Z reporter plasmid encoding β-galactossidase, were used to measure the estrogen-like compounds in the farm wastewater treatment plant. Results The wastewater samples from influents showed a higher estrogenic potency than the effluent samples showing a low induction of β-galactossidase relative to solvent control condition. By comparison with a standard curve for 17β-estradiol (E2), estrogenic potency in water samples from the influents was calculated as E2-equivalent and ranged from 0.1 to 150 pM E2-equivalent. The estrogenic potency in water samples from the effluents was significantly lower than that in the influents, and 7 water samples had less detectable limit in the total of 9 samples. Conclusion Yeast bioassay of estrogenic activity in most of the samples from the farm wastewater after disposal by traditional sewage treatment showed negative results.

To study the effect of endocrine disruptor chemicals in cow milk on female reproductive system.A two-generation reproduction was conducted according to U. S. FDA standard. Milk was fed in special bottle to Wistar rats of both sexes through two successive generations (F0 and F1) in the milk group while artificial milk was fed to rats in the control group. Twenty-four rats of each sex were mated in each group. Measurements were made according to this guideline.Reproductive parameters in the milk group such as fertility index, gestation index, weights of uterus and ovary, days of vaginal opening, estrous cycles, histological morphological changes were comparable to those in the control group. However, the means of body weight had some differences. The body weight gains increased significantly in the milk-treated group in F1 and F2 generation compared with those in the control group. The concentration of insulin-like growth factor-1 (IGF-1) in blood in the milk group was comparable to that in the control group, but the standard deviation changed greatly in the milk-treated rats.Endocrine disruptor chemicals in milk have no severe effects on the female reproductive system.

The fermentation of Streptomyces griseus for the production of cycloheximide is similar to other antibiotic fermentations in that product synthesis is subject to feedback regulation and the desired product is degraded in the fermentation broth. The productivity of this fermentation can thus be dramatically increased by removing the antibiotic from the whole broth as it is produced. One means for effecting this on-line product removal is to contact the whole fermentation broth with neutral polymeric resin immobilized in hydrogel beads. The antibiotic adsorbs to the immobilized resin via hydrophobic interactions. In this work, the adsorption of the antibiotic onto the immobilized resin was characterized. A biochemical model of the fermentation was then used to describe the time profiles of biomass, substrate, and antibiotic in a fermentation system in which whole broth is circulated from the fermentor through a continuously stirred extractor containing the adsorbent beads. Various operating conditions were examined to optimize the productivity of the fermentation.

Biosensors with animal and microbial cells immobilized close to the tip of a membrane electrode have been developed for chemical and drug testing. Our experimental results show that biosensors can be used for drug screening and to provide useful information about various cell-chemical interactions. A computer aided analysis (CAA) software package is being developed here using the biosensor for various screening purposes. This software package enables us to use a computer to analyze the biosensor dynamic responses. Computer simulation and parameter estimation techniques are used to select the best model and to describe the biochemical and pharmacologic effects of various chemicals and drugs on different cell lines.

Transient mode dissolved oxygen measurement has been studied using a specially constructed galvanic membrane electrode controlled by a microcomputer. A four-layer difj%sion model was developed to describe the dynamic behavior of the electrode. The data interpretation method is based on on-line computer simulation and parameter estimation techniques. A user-friendly computer software package is aLro developed for calibration and measurement control. Both experimental and theoretical studies indicate that such measurement is less sensitive to fouling and changes in flow conditions than steady state operation of the electrode.

Biosensors based on immobilized microbial cells were developed for drug screening in our laboratory. Compared with the conventional methods such as diffusion and dilution tests, biosensors have been demonstrated to be superior in sensitivity and require much shorter screening time. An integrated microcomputer system has been developed for data acquisition, database management, and mode of action estimation, which automates the screening processes and reduces the labor requirements significantly.