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Transformation of the microstructure of molybdenum disilicide heating unit in nitrogen atmosphere at 1700°C was investigated by XRD, SEM and EDS. The results showed that MoSi2 was transformed to polyhedral Si3N4 crystals groups distributed across in the matrix with irregular geometry Mo5Si3 and Mo3Si crystals, and the Si3N4 crystal groups were dense areas, while the Mo5Si3 and Mo3Si groups were loose areas after being heated in nitrogen atmosphere at 1700°C for 3h. The thickness of conversion zone of MoSi2 matrix was about 30μm and the loose Mo5Si3 and Mo3Si areas can damage the dense structure of MoSi2 matrix.

Single phase YIG powders were synthesized successfully using Fe2O3 and Y2O3 as starting materials by solid state reaction, and YIG ceramics were prepared by pressureless sintering. The influence of synthesizing temperature and Fe2O3 content on the final production were studied The effect of Fe2O3 content on volume density and microstructure of the sintered YIG was also investigated. The results showed that single phase YIG powders were synthesized by solid state reaction at 1400°C for 3h. When Fe2O3 content was excessive 3 wt%, YIG ceramics with a density of 5.294g·cm-3 was fabricated by sintering at 1480°C for 2.5h.

The phase transformation of Tangshan ironstone-tailings between 900°C ~1200°C in air was investigated by DTA-TG. XRD and SEM analyses indicated that the ironstone-tailings, sintered at 900° and 1000°C respectively, mainly were composed of α-quartz, anorthite [(Na0.45Ca0.55)(Al1.55Si2.45O8)], tremolite and a little of hematite. For the sample sintered at 1100°C, augite appeared and tremolite disappeared. Fayalite formed in the sample sintered at 1200°C. The two samples both exhibited contraction character in the range of experimental temperature.

N-doped TiO2 nanostructured composite (TiO2-N) films with excellent photocatalytic performance under visible light were successfully formed on glass and stainless steel substrates by spin-coating process. The photoreduction performance of as-prepared coatings was characterization by reduction of Ag+ and measurement of photovoltaic response. It was found that Ag+ can be easily reduced to metallic Ag and obvious photocurrent and photovoltage were observed by V-I recording under visible light irradiation. Crystalline structure, nitrogen states in the lattice, composition and surface morphology of the nanostructured films were analyzed by XRD, XPS and SEM.

Fe-SiAlON-MoSi2 composites were prepared using FeSi75, α-Al2O3, and MoSi2 powders as starting materials at 1400 oC, 1500 oC, 1600 oC and 1700 oC, respectively, for 3h in a flowing nitrogen under the pressure of 0.9MPa. The results showed that the main phases of Fe-SiAlON-MoSi2 composite were β-SiAlON with deferent Z-values, MoSi2, and Fe3Si. Z-value of the obtained β-SiAlON depanded on α-Al2O3 content and the sintering temperature. The morphology of SiAlON phase changed from fibre-like of low Z-value to hexagonal prism-like of high Z-value.

High pressure die casting is the most common method in making magnesium alloys for both auto parts and 3C products. Pressure variations in the mold during mold filling and solidification process have direct influences on the quality and properties of die castings. In this paper, a cylinder head cover was produced to experimentally study pressure variations in the mold during magnesium alloy die-casting process in real time for the first time. Pressure varies at different positions in the mold during die casting process. This study indicates that mold filling and solidification process of magnesium alloy die castings can be described by pressure curves obtained by pressure measurement at different test positions in the cavity in real time.

A variety of benzothiazepinone derivatives (V) (25 examples) are synthesized as novel non-ATP competitive inhibitors of GSK-3β based on the cyclization of 2-aminobenzenethiol with acrylic acids.

To observe the effects of different ways in repairing scrotum of pigs with full-thickness burn on spermatogenesis of testis.Twenty male Guizhou miniature pigs were divided into normal control (NC), natural-healing (NH), flap-repairing (FR), and skin-grafting (SG) groups according to the random number table, with 5 pigs in each group. Pigs in NC group were not subjected to any injury. Scrotum of pigs in the latter three groups were inflicted with full-thickness burn. Wounds in NH group healed naturally. Wounds in FR group were repaired with inguinal region flap, and those in SG group with full-thickness skin from lower abdomen. Appearance of scrotum in the latter three groups was observed right after injury, and three months post injury or surgery (PIM or PSM). Specimens of testes of pigs in the latter three groups were obtained in PIM or PSM 3 to detect apoptosis of spermatogenic cells with TUNEL, and bcl-2 protein expression with immunohistochemistry. The same indexes were observed and determined in pigs of NC group. Data were processed with one-way analysis of variance and LSD test.(1) Scrotum of pigs in NC group had skin folds with contraction function. Scrotum of pigs became hard with a leathery appearance right after burn in the other three groups. In PIM or PSM 3, wounds of pigs in NH group healed with scar, and the testes were squeezed into inguinal region. Scrotal skin of pigs in FR group was thick with testes in the scrotum, and that of pigs in SG group was thin with testes in the scrotum. (2) Spermatogenic cells in each level in NC group were arranged regularly, with few apoptotic spermatocytes and spermatoblasts. In NH, FR, and SG groups, seminiferous epithelium was thinner with most of the spermatogenic cells showing apoptosis, and they were mainly spermatogonia and spermatocytes. Apoptotic index of spermatogenic cells in NH, FR, SG, and NC groups was respectively (46.3 ± 3.3)%, (40.9 ± 3.5)%, (20.6 ± 2.3)%, (7.5 ± 1.9)%, and the difference among them was statistically significant (F = 405.65, P0.01). There were significant statistical differences among the former three groups (with P values below 0.01). (3) bcl-2 protein expression in NH, FR, SG, and NC groups was respectively (52 ± 5)%, (53 ± 4)%, (64 ± 5)%, (75 ± 5)%, and the difference among them was statistically significant (F = 56.63, P0.01). There was no significant statistical difference in bcl-2 expression between NH group and FR group (P = 0.66), and it was lower in both groups as compared with SG group (with P values below 0.01).Either scar healing, flap transplantation, or SG in repairing scrotum with full-thickness burn in pigs inhibits spermatogenesis, but repair with SG produces less deleterious effect on the testis.

Glycogen synthase kinase-3β (GSK-3β) is an important serine/threonine kinase that has been proved as a key target for neurodegenerative diseases and diabetes. Up to date, most of known inhibitors are bound to the ATP-binding pocket of GSK-3β, which might lead widespread effects due to the high homology between kinases. Recently, some of its non-ATP competitive inhibitors had been confirmed having therapeutical effects owing to their high selectivity. This finding opens a new pathway to study hopeful drugs for treatment of these diseases. However, it is still a challenge nowadays on how to efficiently find non-ATP competitors. Here, we successfully discovered a novel scaffold of benzothiazepinones ( BTZs ) as selective non-ATP competitive GSK-3β inhibitors through virtual screening approach. A 3D receptor model of substrate binding site of GSK-3β was constructed and applied to screen against drug-like Maybridge database through Autodock program. BTZ compounds were top ranked as efficient hits and were then synthesized for further screening. Among them, the representative compound 4j showed activity to GSK-3β (IC 50 : 25 μM) in non-ATP competitive mechanism, and nearly no inhibitory effect on other 10 related protein kinases. Overall, the results point out that BTZ compounds might be useful in treatment of Alzheimer’s disease and diabetes mellitus as novel GSK-3β inhibitors. It also suggests, on the other hand, that virtual screening would provide a valuable tool in combination with in vitro assays for the identification of novel selective and potent inhibitors.

High-toughness Sialon ceramic matrix composites containing alloy second-phase particles were fabricated by hot pressing at a relatively low temperature of 1600°C. Substantially improved fracture toughness of 8.0 MPa·m1/2 was achieved through the addition of varying amounts of ferro-molybdenum alloy particles. The microstructure of the composites was characterized and crack propagation behavior was observed to understand the toughening mechanisms. The results showed that crack deflection and crack bridging are the principal mechanisms in the toughening of these types of ceramic composites.

Well-aligned TiO2nanotube arrays were fabricated by anodizing Ti foil in viscous F−containing organic electrolytes, and the crystal structure and morphology of the TiO2nanotube array were characterized and analyzed by XRD, SEM, and TEM, respectively. The photocatalytic activity of the TiO2nanotube arrays was evaluated in the photocatalytic (PC) and photoelectrocatalytic (PEC) degradation of methylene blue (MB) dye in different supporting solutions. The excellent performance of ca. 97% for color removal was reached after 90 min in the PEC process compared to that of PC process which indicates that a certain external potential bias favors the promotion of the electrode reaction rate on TiO2nanotube array when it is under illumination. In addition, it is found that PEC process conducted in supporting solutions with low pH and containing Cl−is also beneficial to accelerate the degradation rate of MB.

To investigate the prevalence of love affairs and intimate partner violence, and to explore the relationship between intimate partner violence and other mental health and risk behavior in college students.Three universities were selected using cluster sampling method in Hefei and Wuhu. Totally, 2575 college students completed an anonymous questionnaire. Intimate partner violence, depression, satisfaction of school life, self-esteem, suicidal psychology and behavior were evaluated to estimate the relationship between intimate partner violence and mental health/risk behavior.There were 46.9% students reported that they had intimate partner currently or in the past. The rate of having intimate partner in male students was higher than that in female students (χ(2) = 44.13, P0.001). And the rates were higher in sophomores and juniors than in freshmen (χ(2) = 161.84, P0.05). There were 21.1% students had sexual behavior with their intimate partners. But only 21.8% (34/156) intimate partners reported that they used condom every time. There were 11.5% (18/156) intimate partners reported that they never took any contraception. There were 18.6% (29/156) students reported that they were pregnant or led to their girlfriend becoming pregnant, but only less than 50.0% adolescents induced abortion in a legal hospitals. The rates of being the victim of physical assault, emotional abuse, sexual coercion, the total intimate partner violence were 18.0%, 33.6%, 5.1%, 37.1%. The rates of being the victim of physical assault, emotional abuse, total intimate partner violence in male adolescents were higher than those in female adolescents, but the rate of sexual coercion was on the contrary (χ(2) = 70.21, 13.25, 14.04, 5.77, P0.05). Among the intimate partners who had suffered from intimate partner, 74.2% (345/446) students had underwent more than 3 times, and 47.1% had underwent more than 2 types of intimate partner violence. The score of depression was highest in the victims of intimate partner violence, but the scores of self-esteem and school life satisfaction were on the contrary (F = 4.00, 16.39, 8.76, P0.05). The rates of suicidal ideation, suicidal plan, suicidal preparative and attempted suicide were highest in the victims of intimate partner violence (χ(2) = 13.80, 9.72, 8.52, 11.96, P0.05).The rate of having sexual behavior with their intimate partners was high in college students, but their self-protection awareness was insufficient. In the present study, a high prevalence of intimate partner violence among university students was observed, and highlighted a need for attention to the other mental health and risk behavior in adolescents with intimate partner violence.

To investigate the episodes and influencing factors on self-harm and to explore the relationship between self-harm episodes and suicidal psychology and behaviors in college students.Four universities were selected using cluster sampling method in Anqing city and Chaohu city. Totally, 2713 college students completed this survey. Data were analyzed by Pearson Chi-square and logistic regression.In the last six months, rates of highly lethal self-harm, less lethal self-harm with visible tissue damage, self-injury without visible tissue damage, self-harmful behaviors with latency damage, other self-harmful behaviors with menticide were 1.9%, 5.5%, 15.3%, 21.2% and 17.0% respectively. The total rate of self-harm was 31.3%. 73.1% of the students with self harmful experiences had the above mentioned behaviors more than 3 times in the last six months. The top 3 reasons for taking self-harm actions were: having learning problems (43.1%), failed love affairs (25.0%) and having conflicts with others (23.9%). There were different influencing factors among different kinds of self-harm episodes. Depression was the risk factor of self-harm. The higher score of having high self-esteem was the protective factor of all kinds of self-harm actions except highly lethal ones. Higher score of difficulties in identifying feelings was one of the risk factors. The rates of suicidal psychology and behaviors in students with self-harm were significantly higher than those in students without those behaviors. Result from linear χ(2) test indicated that the graveness of tissue damage of self-harm was higher along with the rates of suicidal psychology and behaviors (P0.01).Among 2713 college students, about 1/3 adolescents having experienced self-harm in the last 6 months, many with repeated ones. Depression and difficulties in identifying feelings were the two risk factors while self-esteem was the protective factor related to most of the self-harm cases.

To examine the epidemiological features and relative risk factors of repeated injuries among middle, high and college students in Ma'anshan city of Anhui province.A prospective study on repeated injuries for 1-year follow-up period was carried out among 1494 students from 3 middle schools or colleges. Risk factors for repeated injuries were analyzed with multivariate logistic regression model.799 students suffered 1639 episodes of injuries, with an incidence rate of 53.48%. The repeated group consisted of 200 students who suffered 854 injuries, accounted for 52.10% among the total injuries.from Multi-normal logistic regression analysis showed that male, number of family members of 4 or over, extraversion of character trait, and upper quartile of self-rating anxiety symptoms were the risk factors for the occurrence of repeated injuries. Moderate or well-of family income, mothers with senior high school education, and upper quartile of self-rating depression symptoms were protective factors for repeated injuries.Socio-demographic factors and emotional status may predict the occurrence of repeated injuries that called for further study.

To construct chimerical DNA vaccine plasmid of human papillomavirus type 11 (HPV11) L1-E7, and to evaluate its immunogenicity.Molecular cloning techniques were used to construct recombinant plasmid pcDNA3 L1-E7 as a DNA vaccine. BALB/c mice were vaccinated with DNA recombinants through muscle injection.IL-2 and gamma-INF secreted by immunized spleens lymphocyte and HPV 11 L1 or E7 specific antibodies were assayed by ELISA method. Spleens lymphocyte proliferation was measured by MTT assay.The chimerical DNA plasmid of pcDNA3 L1-E7 was constructed correctly. Specific anti-HPV11 E7 and L1 antibodies, specific lymphocyte proliferation and secretions of IL-2 and gamma-INF were detected in vaccinated mice.Specific immune response, including cellular immunity and humoral immunity, could been detected in mice vaccinated with chimerical DNA vaccine of pcDNA3 L1-E7.

To examine life satisfaction as a moderator or mediator of accommodation category and loneliness for elementary and middle school students in rural areas so as to provide evidence for psychological health intervention among said students.All participants were asked to complete an anonymous questionnaire battery which including an 18-item General Health Questionnaire, Children's Loneliness Scale and Multidimensional Students' Life Satisfaction.The average score of loneliness scale (35.0 +/- 9.5) among boarding-school students was significantly higher than those students living at home (33.1 +/- 10.1) (P0.01). The average scores on school-satisfaction (33.5 +/- 6.3), friend-satisfaction (42.1 +/- 6.2) and self-satisfaction (32.4 +/- 5.0) of boarding-school students were significantly higher than those students living at home (35.9 +/- 6.6, 42.9 +/- 6.6, 32.9 +/- 5.3) (P0.05). The association between accommodation category and loneliness was fully mediated by school-satisfaction (the standardized coefficients of loneliness was reduced from 0.043 (P0.05) to 0.021 (P0.05) and partly mediated by self-satisfaction and friend-satisfaction. Data through Moderation analyses indicated that self-satisfaction, school-satisfaction and friend-satisfaction did not serve as moderators.Accommodation category, life satisfaction seemed to be good predictors on loneliness among elementary and middle school students and the fully mediated effect of school-satisfaction between accommodation category and loneliness was significant, suggesting that intervention of loneliness should focus on these variables.

This paper briefly reports on research and applications of medical piezoelectrical ceramic ultrasonic transducer materials, high-performance medical ultrasonic imaging transducers in present work, then, some problems of the piezoelectric materials and devices used for the ultrasonic medicine which need further researches are pointed.

To investigate the expression of the T cell-specific transcription factors T-bet/GATA-3 in recurrent aphthous ulcerations (RAU).Peripheral blood mononuclear cells (PBMC) were isolated by density gradient centrifugation from RAU patients and healthy controls. Expressions of T-bet and GATA-3 mRNA and protein in the PBMCs were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot respectively. The concentrations of gamma-interferon (gamma-IFN) and interleukin-4 (IL-4) in the serum were determined by enzyme-linked immunosorbent assay (ELISA).The expressions of T-bet mRNA were 0.73 +/- 0.14 in the control group and 0.12 +/- 0.04 in the recurrent aphthous ulcerations group, the levels of T-bet protein expressions were 0.73 +/- 0.18 in the control group and 0.24 +/- 0.09 in the recurrent aphthous ulcerations group, there was a significant difference between the two groups (P0.01). The levels of GATA-3 mRNA expressions were 0.89 +/- 0.11 in the control group and 1.30 +/- 0.13 in the recurrent aphthous ulcerations group; GATA-3 protein expressions were 1.09 +/- 0.16 in the control group and 1.80 +/- 0.16 in the recurrent aphthous ulcerations group, there was a significant difference between the two groups (P0.01). In the control group, the concentration of gamma-interferon in the serum was (22.15 +/- 1.52) ng/L, which was significantly elevated compared with that in the recurrent aphthous ulcerations group (16.32 +/- 0.22) ng/L (P0.01), in the control group, the concentration of IL-4 in the serum was (25.58 +/- 2.59) ng/L, which was significantly lower than that of the recurrent aphthous ulcerations group (43.60 +/- 3.15) ng/L (P0.01). The ratio of gamma-IFN and IL-4 was positively correlated with the ratio of T-bet and GATA-3 mRNA and protein expression (r = 0.96, 0.94, P0.01).Imbalance of transcription factors T-bet and GATA-3 may be one of the key factors in immune dysregulation of recurrent aphthous ulcerations.

To study the antihyperlipidemia effective constituent of Polygala fallax Hemsl.Column chromatographic techniques were employed for isolation and purification of chemical constituents of the plant and the structures were elucidated by IR, NMR and MS spectroscopy.Four triterpenoid saponins were isolated and determined as 3-O-beta-D-glucopyranosyl-( 1--2) -beta-D-glucopyranosyl presenegenin 28-O-beta-D-xylopyranosyl-(1--4 ) -alpha-L-rhamnopyranosyl-(1--2 ) -beta-D-fucopyranosyl ester (I), 3-O-beta-D-glucopyranosyl-(1--2) -beta-D-glucopyranosyl presenegenin 28-O-beta-D-xylopyranosyl-(1--4) -alpha-L-rhamnopyranosyl-(1--2) -(3-O-acetyl)-beta-D-fucopyranosyl ester (II), 3-O-beta-D-glucopyranosyl-(1--2) -beta-D-glucopyranosyl presenegenin 28-O-beta-D-xylopyranosyl-(1--4) -alpha-L-rhamnopyranosyl-(1--2) -(4-O-acetyl) -beta-D-fucopyranosyl ester (II) and 3-O-beta-D-glucopyranosyl-(1--2) -beta-D-glucopyranosyl presenegenin 28-O-beta-D-xylopyranosyl-(1--4 ) -alpha-L-rhamnopyranosyl-(1--2 ) - (3,4-diacetyl) -beta-D-fucopyranosyl ester (IV).The effective constituents of Polygala fallax Hemsl. reduced blood lipid especially plasma TG markedly. The authors have studied the chemical constituents of effective constituent systematically for the first time.

To study the chemical constituents of Polygala aureocauda Dunn..Chemical compounds were isolated by column chromatography and their structures were determined mainly by spectroscopic means (UV, IR, MS, 1HNMR, 13CNMR, HMQC, HMBC).Three compounds were isolated and identified as 3-hydroxy-1,4-dimethoxyxanthone (I), 1, 7-dihydroxy-2, 3-methylendioxyxanthone (II), 7-hydroxy-1-methoxy-2, 3-methylendioxyxanthone (III).Compounds I-III were isolated from Polygala aureocauda Dunn. for the first time, whereas compound I is a new xanthone.

Acute hepatic failure was induced experimentally in rats by intraperitoneal injection of 2.5 mL kg−1 carbon tetrachloride (CCl4), and the effects on the expression and function of P-glycoprotein in the liver, kidney and brain were evaluated. The CCl4 injection significantly increased the indicators of hepatic function (glutamate oxaloacetate transaminase, glutamate pyruvate transaminase), but not of renal function (blood urea nitrogen, glomerular filtration rate). In rats with acute hepatic failure, the hepatic P-glycoprotein concentration increased 1.5-fold and the ATP concentration decreased to approximately 40% that in control rats. In contrast, P-glycoprotein concentrations in the kidney and brain and ATP concentrations in the kidney remained unchanged. The in-vivo P-glycoprotein function in these tissues was suppressed as evaluated by biliary and renal secretory clearances and brain distribution of rhodamine 123, a P-glycoprotein substrate. These findings suggest that factors other than P-glycoprotein concentration are involved in the systemic suppression of P-glycoprotein function in diseased rats. In Caco-2 cells, plasma collected from CCl4-treated rats exhibited a greater inhibitory effect on P-glycoprotein-mediated transport of rhodamine 123 than that from control rats, suggesting the accumulation of an endogenous P-glycoprotein substrate/inhibitor in the plasma of diseased rats. In fact, the plasma concentration of corticosterone, an endogenous P-glycoprotein substrate, increased 2-fold in CCl4-treated rats compared with control rats. It was demonstrated that P-glycoprotein function is systemically suppressed in rats with CCl4-induced acute hepatic failure, not only in the target organ (liver), but also in other organs (kidney and brain), although the P-glycoprotein concentration remained unchanged in the kidney and brain, and increased in the liver. In the systemic suppression of the P-glycoprotein function in the diseased state, the alteration of plasma concentrations or components of endogenous P-glycoprotein-related compounds, such as corticosterone, would likely be involved.

TiO2 nanotube array was fabricated via anodization, and the resulting film was investigated by XRD and SEM. The degradation of Methylene Blue (MB) dye demonstrated its superior photoelectrochemical...

Ni/Al-Al2O3 gradient ceramic coating was prepared on Q235 steel by plasma spraying. Microstructure and corrosion behavior in boiling 5%HCl solution of the samples sprayed with this coating were investigated. The results showed that thickness of Al2O3 ceramic coating was increased greatly and almost no connected pores formed in the gradient coating due to the existent of Ni/Al-Al2O3 transition interlayer coatings. The corrosion resistance of Q235 steel with Ni/Al-Al2O3 gradient composite ceramic coating in boiling 5%HCl solution was greatly improved.

The corrosion behavior of BF slag to sialon bonded corundum refractories using reaction nitriding technology at 1500°C was investigated by crucible test method. The results show that the reaction products of slag corrosion are anorthite, magnalium-spinel and glass phases. The corundum grains can react with MgO in the slag to produce magnalium-spinel, accompanying by expansion and liquating stepwise by slag. Erosion mechanism is oxidation-erosion-dissolving. This study is very necessary and useful to improve the property of BF slag resistance and to yield better overall properties of sialon bonded corundum refractories.