Site testing campaign for the Large Optical Telescope at the Ali site

The Large Optical/infrared Telescope(LOT)is a ground-based 12 m diameter telescope which is proposed to be built in western China.The site selection for LOT in China began in 2016,and Ali was listed as one of the three candidate sites.Remote studies and local surveys have been carried out for more than 15 years in western China,and the results show that Ali is a promising site with comprehensive quality in terms of atmospheric and supporting conditions.An overview of the site testing campaign at the Ali site from 2016 to 2019 is presented.After the two years of data collection,the overall median seeing value is found to be 1.17 arcsec,the observable nights are 81.71%and the good observable nights are 71.76%.The weather conditions as follows,the median night temperature value is-5.18℃,the median night relative humidity value is 41.25%,the median night atmospheric pressure value is 540.92 hPa,the median night wind speed value is 7.41 m s-1 and the mainly wind direction is southwestern(SW).The median night sky background value is 22.07 magV.We also discuss the wind speed at different locations on-site,the possibility of light pollution and the effect of wind speed on differential image motion monitor(DIMM)seeing measurements.

STUDY ON THE IMMOBILIZATION OF PAPAIN WITH A MACROPOROUS BEAD CARRIER OF COPOLYMER CONTAINING MONOMER UNITS OF NAMINOETHYL ACRYLAMIDE AND VINYL ALCOHOI

A kind of macroporous bead carrier of copolymer containing monomer units of N-aminoethyl acrylamide and vinylalcohol was synthesized, i.e. the MR-AA carrier. Papain was immobilized on the carrier using glutaraldehyde as the couplingagent. The enzymatic activity of the immobilized papain was compared with free papain using casein as a substrate, and theeffects of glutaraldehyde concentration, pH, temperature, time and papain amount added on the activity recovery were alsoinvestigated. The results show that the MR-AA carrier contains reactive primary amine groups, hydrophilic amido links andhydroxyl groups, as well as macroporous structures based on its matrix (MR-AV matrix), furthermore, the activity recoveryof papain in the immobilization could reach 48%/～58%. In comparison with free papain, the resulting immobilized papainexhibits a remarkable thermostability and better reusability.

Effects of Zn^(2+) and Cu^(2+) on loach ovaries and ova development

This study compared the accumulation of Zn2+and Cu2+in the ovaries and ova of loaches under different concentrations of Zn2+(1.00, 2.50 and 5.00 mg/L respectively) and Cu2+(0.10, 0.25 and 0.50 mg/L respectively). The results showed that both Zn2+and Cu2+accumulated in the ovaries, and that the relationship between accumulation and time was linear over 20 days of exposure. The accumulation of the metals in ovaries was closely related to the concentration of exposure in the solutions(P<0.05), and was obviously affected by the time and doses. However, the Cu2+concentration was significantly higher than Zn2+(P<0.05). The development level of ova in the ovaries also correlated with the concentration and exposure period in the Zn2+and Cu2+solutions.

急性重症溃疡性结肠炎的治疗

急性重症溃疡性结肠炎(acute severe ulcerative colitis,ASUC)是一种医疗紧急情况,有危及生命的风险.随着近年来溃疡性结肠炎发病率的不断上升,临床上ASUC也愈发常见.目前激素仍是主要治疗手段,激素治疗3 d后应评估疗效,疗效欠佳时及时转换为英夫利昔单抗或环孢素抢救治疗,内科治疗效果欠佳或发生严重并发症时,可选择结肠切除术.本综述阐述了目前ASUC常用治疗方案,有助于临床医疗决策的制定,改善患者预后,并提高患者生活质量.

Effects of Zn^(2+) and Cu^(2+) on loach ovaries and ova development

This study compared the accumulation of Zn^(2+)and Cu^(2+)in the ovaries and ova of loaches under different concentrations of Zn^(2+)(1.00,2.50 and 5.00 mg/L respectively)and Cu^(2+)(0.10,0.25 and 0.50 mg/L respectively).The results showed that both Zn^(2+)and Cu^(2+)accumulated in the ovaries,and that the relationship between accumulation and time was linear over 20 days of exposure.The accumulation of the metals in ovaries was closely related to the concentration of exposure in the solutions(P<0.05),and was obviously affected by the time and doses.However,the Cu^(2+)concentration was significantly higher than Zn^(2+)(P<0.05).The development level of ova in the ovaries also correlated with the concentration and exposure period in the Zn^(2+)and Cu^(2+)solutions.

The association between disruption of the circadian rhythm and aggravation of colitis in mice

Delayed recovery from ulcerative colitis is mainly due to impaired healing of the intestinal epithelium after inflammation.The circadian rhythmcontrols cell proliferation and energy metabolism.However,the role of circadian genes in inflammatory bowel disease is largely unknown.The purpose of this study was to investigate whether disrupting the circadian rhythm in mice can worsen colitis by altering mitochondrial energy metabolism.Mice in the experimental groups were under physiologic stress with an 8-h light shift jet-lag schedule every 3 days,whereas those in the control group were not.Subsequently,half of the mice in the control and jet-lagged groups were given dextran sodium sulfate(DSS)to induce colitis.Mice in each group were euthanized at zeitgeber time(ZT)0,ZT4,ZT8,ZT12,ZT16,and ZT20.To investigate the effects of jet lag on the mice,colon specimens were subjected to hematoxylin and eosin staining to analyse mRNA and protein expression of core circadian clock genes(Bmal1,Clock,Per1,Per2,Cry1,Cry2,and Nr1d1).We analysed the mitochondrial morphology,adenosine triphosphate(ATP)levels,and the expression of dynamin-related protein 1(Drp1)and ser637-phosphorylated(p)-Drp1,which are closely related to ATP production.We further investigated the effect of PER2 knockdown in the colon epithelial cells(CCD 841 CoN)by measuring ATP and cell proliferation levels.Disrupting the circadian rhythm changed the oscillation of clock genes in the colon of mice,altered the mitochondrial morphology of the colon specimens,decreased the expression of p-Drp1,reduced ATP production,and exacerbated inflammatory responses in mice with DSS-induced colitis.Additionally,silencing of PER2 in the colon epithelial cells reduced ATP production and cell proliferation.Disrupting the circadian rhythm in mice decreases mitochondrial energy metabolism in the colon and exacerbates symptoms of colitis.

Induction of follicular luteinization by equine chorionic gonadotropin in cyclic guinea pigs

The effects of equine chorionic gonadotropin （eCG） on follicular development and ovulation in cyclic guinea pigs were investigated by histological and immunohistochemical analyses. Three groups of guinea pigs （n=12） were administrated subcutaneously with saline, 20 or 50 IU of eCG, respectively, on cyclic Day 12 （Day 1=vaginal openings）. Ovaries were collected at 4 and 8 d after administration （6 animals per group each time）. The eCG administration induced significant and distinct morphological changes in the ovaries, as it promoted the luteinization of granulosa cells, but not follicular development. In addition, proliferating cell nuclear antigen （PCNA） and steroidogenic acute regulatory protein （STAR） were immunolocalized specifically in luteinized follicles. Our experiments together indicate that eCG administration can induce follicular luteinization but not superovulation in guinea pigs. The eCG in cyclic guinea pigs functions similar to that of luteinizing hormone （LH）, but not follicle-stimulating hormone （FSH）.