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In this paper, sandwich rolling with symmetrical thickness and materials is intensively studied. The inner metal is out of touch with both upper and lower rolls in the sandwich sheets, and all the forces are delivered from upper and lower sheets. This special character makes the relative slip distance and elongation distance appear. Then, the defected length is formed during the sandwich rolling. It verifies that the point where both inner and outer metals have the same velocity is also the point where the two metals are both deformed. Slab method is first applied in predicting the defected length of the sandwich sheets. Sandwich rolling experiments with aluminum and copper are conducted. The results obtained in this paper are also compared with those measured in experiments and calculated by stream function model recorded in references. So the model can be used in the real work conditions. It is helpful to find the best shearing position in the head of the sandwich sheets. The cost of materials is reduced based on the present model. When sheets are rolled in continual rolling passes, the defected length can be more important and serious. Specifically, if the sheets are wide, expensive and multilayer, the shearing position can be more significant to the industrial application.

To establish a LC-MS/MS method which is accurate and sensitive for determination of koumine, gelsemine, and gelsenicine in biological samples and to verify the method.Strychnine was used as internal standard. Analytes in blood, urine and liver with 1% sodium hydroxide solution were extracted by ethyl acetate. Chromatographic separation was achieved on a ZORBAX SB-C₁₈ column （150 mm×2.1 mm, 5 μm）, and gradient elution was performed with the buffer solution of methanol-20 mmol/L ammonium acetate （including 0.1% formic acid and 5% acetonitrile） as mobile phase. Qualitative and quantitative analysis was performed in the multiple reaction monitoring mode coupled with an electrospray ionization source under positive ion mode（ESI⁺）.The linearity of koumine, gelsemine and gelsenicine in blood, urine and liver was good within corresponding linear limitation and the correlation coefficients （The method is selective, sensitive and suitable for simultaneous determination of koumine, gelsemine and gelsenicine in body fluids and tissues, which offering technical support for clinical diagnosis and treatment and forensic toxicological analysis of

To investigate the clinical efficacy of minimally invasive 23G vitrectomy combined with chandelier for the treatment of superior bullous rhegmatogenous retinal detachment (SBRRD).A retrospective case series study of 50 patients with SBRRD was conducted. Each of these patients received minimally invasive 23G vitrectomy in one of their eye. A trocar was indwelled with two-step 23-G incision, and the chandelier was inserted in the inferior 6 o'clock pars plana. The tear was closed with 23-G vitrectomy combined with endolaser photocoagulation and infused with perfluoropropane (C3F8) under non-contact wide-angle lens. Postoperative follow-up ranged from 5-49 months (mean 23.9±1.3 months). Intraoperative and postoperative complications, postoperative conjunctival hyperemia, eye irritation signs and inflammation reactions, retinal anatomic reduction rate, best corrected visual acuity (BCVA) and intraocular pressure (IOP) changes were analyzed.The intraoperative scleral incision leakage required 17 sutures (34%). No complications, such as iatrogenic retinal breaks and hemorrhage occurred. The postoperative conjunctival hyperemia, eye irritation signs and inflammation reactions were mild. Transient low IOP occurred in one eye (2%) on the first day postoperatively and recovered on the next day. Transient low IOP occurred in eyes of 16 subjects (32%) and recovered after lowering IOP therapy within an average of 4 days. No complications, such as hemorrhage, effusion, choroidal detachment and endophthalmitis were observed. Forty-nine subjects (98%) had retinal reattachment in their eyes after a single surgery, and 100% eyes showed final retinal reattachment. The preoperative and postoperative BCVAs were 4.61±0.19 and 4.70±0.19, respectively, in 8 patients without detached macula, and the difference was not statistically significant (t = 2.20, p0.05).Minimally invasive 23G vitrectomy combined with chandelier is a safe and effective surgical approach for the treatment of SBRRD.

The critical furnace chamber temperature (T′ign) of the thermal explosion synthesis reaction Ti+3Al→TiAl3 is studied by isothermal and non-isothermal DSC. The reaction product is characterized by using the X-ray powder diffraction. The value of T′ign is between 740 and 745°C obtained from the isothermal DSC observations, and 729°C obtained from non-isothermal DSC curves. It shows that these two values have a good consistency. With the help of the apparent activation energy of the reaction obtained by Friedman method and the value of T′ign0 by the multiple linear regression of the T′igns at different heating rates (β), the critical temperature (Tb) of thermal explosion for Ti–75at%Al mixture is estimated to be 785°C.

To determine the curative effect and complications of 23G vitrectomy via corneal approach for the treatment of pediatric cataract.We performed anterior circular capsulotomy, lentectomy and aspiration, posterior circular capsulotomy, and anterior vitrectomy via corneal approach in 40 eyes from 25 children with congenital cataract. In patients aged2 years, foldable intraocular lens (IOL) was implanted and frame glasses were prescribed at younger age. The intraoperative/postoperative complications, comfort level, and inflammatory reaction after surgery were observed.No intraoperative complications occurred and 9 eyes were simultaneously implanted IOL. All patients could blink normally except one child who suffered from corneal epithelial abrasion for one day. All corneas were clear and only mild postoperative inflammation was observed. There was no hyphema, effusion, hypotony, and hypertension. A week later, the mild congestion also disappeared. All parents reported good vision of their babies allowing them free play during 3-50 months follow-up. This surgical technique provided a clear 4-6 mm diameter visual axis and circular pupil in all cases. The IOL positions were centered at the pupil area. No secondary cataract developed.The 23-gauge vitrectomy via corneal approach for the treatment of pediatric cataract involves only mild discomfort and fewer complications.

Fe–B ultrafine amorphous alloy particles (UFAAP) were prepared by chemical reduction of Fe3+ with NaBHO4 and confirmed to be ultrafine amorphous particles by transmission electron microscopy and X-ray diffraction. The specific heat of the sample was measured by a high precision adiabatic calorimeter, and a differential scanning calorimeter was used for thermal stability analysis. A topological structure of Fe-B atoms is proposed to explain two crystallization peaks and a melting peak observed at T=600, 868 and 1645 K, respectively.

The aim of the present study was to elucidate the fundamental mechanism of bovine oviduct epithelial cell (BOEC) co-culture on developmental capacity of bovine in vitro oocyte maturation/in vitro fertilization (IVM/IVF) embryos. We examined the effects of astaxanthin against nitric oxide-induced oxidative stress on cell viability by MTT assay, lipid peroxidation (LPO) by using thiobarbituric acid (TBA) reaction for malondialdehyde (MDA) and the expression of antioxidant genes (CuZnSOD, MnSOD and Catalase) or apoptosis genes (Bcl-2, Caspase-3 and Bax) by RT-PCR in BOEC. We also evaluated the developmental rates of bovine IVM/IVF embryos co-cultured with BOEC pre-treated with astaxanthin (500 μM) in the presence or absence of sodium nitroprusside (SNP, 1000 μM) for 24 h. Cell viability in BOEC treated with SNP (50-2000 μM) lowered, while astaxanthin addition (50-500 μM) increased it in a dose-dependent manner. Cell viability in astaxanthin plus SNP (1000 μM) gradually recovered according to the increase in astaxanthin additions (100-500 mM). The LPO in astaxanthin group (50-500 μM) gradually decreased in a dose dependent manner and among SNP or astaxanthin plus SNP group, SNP alone and astaxanthin (50 μM) plus SNP shown a significant increase than other groups (p 0.05). Expression of apoptosis or antioxidant genes was detected by RT-PCR. Bcl-2 and antioxidant genes were detected in astaxanthin or astaxanthin plus SNP group, and Caspase-3 and Bax genes were only found in SNP group. When bovine IVM/IVF embryos were cultured for 6-7 days under co-culture system such as BOEC treated with astaxanthin in the presence or absence of SNP, the developmental ability to blastocysts in 500 μM astaxanthin group was the highest of all groups. These results suggest that astaxanthin has a antioxidative effect on cell viability and LPO of BOEC, and development of bovine IVM/IVF embryos due to the induction of antioxidant genes and suppression of apoptosis genes.

"The objectives of this paper are to determine the relationship between racial residential segregation and (1) the spatial concentration of low- and high-income households, and (2) the socioeconomic characteristics of racial minority households. The three largest racial minority groups are compared (blacks, Hispanics, and Asians) in the largest 45 metropolitan areas in the United States. Data were obtained from the U.S. bureau of the Census' Population and Housing Summary Tape files. The results revealed that residential segregation of blacks was distinctly different from Asians and Hispanics. Moreover, for Asians and Hispanics, their socioeconomic characteristics matter in their level of residential segregation. For black households, however, their socioeconomic characteristics matter little."

A total of 54 cases (73 hips) with ischemic necrosis of the femoral head after treatment of CDH have been followed up with an average of 7 years. We found that 89% cases of type I and 70% of type II recovered to normal and 83% cases of type III and IV developed the coxa breva deformity due to injury of longitudinal growth plate of the proximal end of the femur. According to the value of ATD, the coxa breva was divided into three types. The L shape growth disturbance line revealed by X-ray is considered as a marker for determination of early epiphyseal plate injury by the authors.

Thirty-four hips were observed radiographically to see the development of the femoral head. The intramedullary pressure was measured in the proximal femur before and after treatment of congenital dislocation of the hips. The intramedullary pressure in the avascular femoral head decreased more obviously than that in the normal head after treatment. A term of "IMP subtraction value" was put forward as an objective index for evaluating the development of the femoral head after treatment of congenital dislocation of the hip.

Intramedullary pressure in the proximal femur was measured before and after treatment of congenital dislocation of the hip. The intramedullary pressure before treatment was higher than that of the control group, and after treatment it was lower as a whole; in the close reduction group the pressure decreased as compared with the operation group. In 8 hips, stress test yielded negative results. These findings suggested the characteristics of arterial blockage may be that the potential cause of avascular necrosis of the femoral head after treatment of congenital dislocation of the hip.