轮胎压出卷取装置的控制系统改进

传统上,轮胎成型机成型时仅胎侧采用卷取方式,胎面采用在压出冷却线上预裁断的方式.近几年,为了提高轮胎的动平衡,轮胎成型用的半成品部件越来越多地采用卷取的方式,现胎面也开始大量采用卷取方式.但使用原有的设备存在卷取的部件厚度变化较大时,卷取速度与生产线速度不匹配的问题,为此,提出了实现方式简单和改动很小的改进的措施.     

玉米秸秆反季栽培双孢蘑菇技术

以玉米秸秆为原料,利用北方日光温室进行反季栽培双孢蘑菇技术试验。试验结果表明,采用夏季发酵培养料、秋季播种、秋冬季节出菇的反季栽培双孢蘑菇技术模式,与北方气候条件基本吻合,再利用日光温室进行出菇,可减少能源消耗。在日光温室条件下用玉米秸秆作主料栽培双孢蘑菇,每平方米产双孢蘑菇10～15kg,可提高菇农的种植效益。栽培后产生的废料还可肥田和改良土壤理化性状,使生物转化率达40%以上。     

Protective mechanism of metallothionein on cultivated rat cardiomyocytes in hypoxic preconditioning

AIM: Studying the mechanism of protective role of metallothionein(MT) in hypoxic preconditioning(HPC) of cultivated rat cardiomyocytes. METHODS:Using the model of hypoxia/reoxygenation of cultivated rat cardiomyocytes. Determining the contents of MT, malonyldialdehyde (MDA)-metabolism product of lipid peroxidation and the activities of Na⁺-K⁺ATPase, Ca²⁺-Mg²⁺ATPase of cardiomyocytes 24h after HPC, also determining the relevant changes after using MT antibody. RESULTS: After 24 h in HPC, the contents of MT and activities of Na⁺-K⁺ATPase, Ca²⁺-Mg²⁺ATPase were obviously higher than those in the control and hypoxia/reoxygenation(P＜0.05), and the contents of MDA were decreased remarkedly (P＜0.01). Then after using MT antibody, the activities of two enzyme were progressively decreased and the contents of MDA were significantly higher than those in the control and MT antibody-free groups(P＜0.01). CONCLUSION: HPC may induce excessive synthesis of MT, and MT can protect myocardial reoxygenation injury by eliminating lipid peroxidation and rising the activities of Na⁺-K⁺ATPase and Ca²⁺-Mg²⁺ATPase.     

Inducible nitric oxide synthase and arterial pressure regulation

AIM and METHODS:To clarify the role of inducible nitric oxide synthase (iNOS) in the regulation of blood pressure,in the present study, we examined the effect of aminoguanidine (AG), a selective inhibitor of iNOS on the hemodinamical response of Dahl salt-sensitive (DS) and Dahl salt-resistant (DR) rats to low (0.3%) or high (8%) sodium chloride (NaCl) infusion by chronical in vivo hemodynamic experiment, and the effect of NaCl or NaCl plus AG infusion on urinary nitrate (NO₃)/nitrite (NO₂), the end product of nitric oxide (NO), excretion by Greiss Reaction. Furthermore, NOS activity assay was also carried out to probe the effect of NaCl and AG on calcium-dependent or independent NOS activity in renal tissue. RESULTS:1. High or low NaCl-infused DR rats and low NaCl-infused DS rats have no hemodinamical response to AG, however, the hypertensive effect of high NaCl (8%) infusion on DS rats were greatly amplified by co-infusion of AG. 2. Administration of high NaCl significantly elevated the iNOS activity of renal tissue, and greatly increased urinary NO₃/NO₂ excretion. CONCLUSION:Inducible NOS is an important modulator of arterial pressure, especially in case of higher blood pressure.     

Some recent advances in the molecular mechanisms underlying senescence

Aging or senescence is a process in which individuals undergo an exponential decline in vitality, leading to death. Recent years, much progress on the molecular mechanisms underlying senes-cence have been made. (1) Some senescence-related gene such as SEN6A, hic-5, dinl and MORF 4 have been clarified; (2) In 1997, through a set of experiments sponsered scientists of Department of Bi-ology Massachusetts Institute of Technology, it was found that the accommulation of extrachromosomal r DNA circles (ERC) in budding yeast s nucleolus is responsible for cell- senescence and the researchers propose that when enough of these circles accumulate, they clog the nucleus and prevent the cell from reading or eplicating its genome, causing it to stop dividing and ultimately to die; (3) In another work finished National Institute on Aging and the Geron biotech company of Melo, it was proved that a cell s biological clock, which tells the cell how and how many times to divide, lies in its telon eres, little bits of DNA that coat the tips of the chromosome and it was clarified that a powerful enzyme, telomerase, with the potential to rejuvenate the human boss aging tissues could effectively extend the shortened telomere.Although there is a long way to go, scientists still believe that it will be made reality in the future to greatly extend the life-span of human.     

Protective effect of C1q/tumor necrosis factor-related protein 3 on vascular endothelium in rats with hyperuricemia

AIM To study whether C1q/tumor necrosis factor （TNF）-related protein 3 （CTRP3）protect vascular endothelium in rats with hyperuricemia and its potential mechanisms. METHODS An animal model of hyperuricemia was established by using male SD rats drinking 10% fructose water （n=10）. The rats drinking normal water served as normal controls （n=10）. After 12 weeks, the rats were given a single injection with Ad-CTRP3 or Ad-GFP. The experiment was ended at 14th day after transfection.The serum levels of uric acid and nitric oxide （NO） were evaluated. The serum contents of TNF-α and interleukin-6 （IL-6） were measured by ELISA. HE staining and TUNEL assay were used to assess the morphological changes of intima and apoptosis of endothelial cells in thoracic aorta, respectively. The mRNA levels of endothelial nitric oxide synthase （eNOS）, TNF-α and IL-6 were detected by RT-qPCR. The protein levels of CTRP3 and Toll-like receptor 4 （TLR4） were determined by Western blot. RESULTS Compared with normal control group, the rats with hyperuricemia showed lower CTRP3 and higher TLR4 protein levels in the thoracic aorta （P<0.05）. Hyperuricemic rats had higher serum contents of uric acid, TNF-α and IL-6 （P<0.05）. Also, the intima structure disturbance of thoracic aorta, increased apoptotic rate, higher mRNA levels of TNF-α and IL-6 as well as lower mRNA levels of eNOS were observed （P<0.05）. By contrast, CTRP3 over-expression decreased TLR4 protein levels, reduced inflammatory cytokines, and obviously improved the morphology and function of thoracic aorta in the rats with hyperuricemia. CONCLUSION CTRP3 protect vascular endothelium in rats with hyperuricemia maybe via down-regulation of TLR4- mediated inflammatory signaling pathway.     

Effects of oxidative stress and inflammatory response on kidney injury in mice with hyperthyroidism

AIM To explore the effects of oxidative stress and inflammatory response on kidney injury induced by hyperthyroidism in mice. METHODS Forty male Kunming mice were randomly divided into control group （n=20） and L-thyroxine （T4） group （n=20）. The mice in T4 group were intraperitoneally injected with T4 diluent at a dose of 1 mg/kg to induce hyperthyroidism, and those in control group were injected with normal saline of the same volume. After 7 weeks, the mice were weighed and dissected, the kidneys were removed and weighed, and the length of tibia was also measured. The activity of superoxide dismutase （SOD） and the content of malondialdehyde （MDA） in the kidney tissues were detected. The pathological changes of the kidney tissues were observed by HE staining. The levels of 4-hydroxynonenal （4-HNE）-modified proteins, interleukin-1 receptor-associated kinase 1 （IRAK1） and tumor necrosis factor receptor-related factor 6 （TRAF6） were determined by Western blot and immunohistochemistry. RESULTS Compared with control group, the body weight of the mice was decreased, while the kidney size and weight were increased significantly in T4 group. In addition, the ratios of kidney weight/body weight and kidney weight/tibia length were also increased （P<0.05）. In T4 group, the renal tubules were enlarged, and the epithelial cells of renal tubules were swollen and exfoliated, with vacuolar degeneration. Furthermore, reduced SOD activity, and increased MDA content and 4-HNE-modified proteins were found in T4 group, all of which were related to oxidative stress （P<0.05）. The levels of inflammation-related proteins IRAK1 and TRAF6 were significantly increased in T4 group （P<0.05）. CONCLUSION Excessive T4 may lead to kidney hypertrophy and injury in mice, and the mechanism may be related to oxidative stress and inflammatory response.     

菠萝蜜类胡萝卜素检测方法研究及呈色物质分析

为研究菠萝蜜果肉类胡萝卜素分析方法、分析呈色组分,本研究基于高效液相色谱法检测果肉中类胡萝卜素组分,通过比较不同色泽果肉中类胡萝卜素物质差异,鉴定呈色组分。结果表明,用含0.01%BHT的正己烷∶丙酮∶无水乙醇(2∶1∶1,V/V/V)作为提取液,结合超声震荡、皂化脱脂等步骤,能有效提取菠萝蜜果肉中总类胡萝卜素。组分分析采用YMC carotenoid column C30(4.6×250 mm)色谱柱,二极管阵列检测器(photodiode array,PDA)在450 nm波长下,检测出16种不同的类胡萝卜素组分。定量结果表明,β-柠乌素是红色果肉的呈色组分,紫黄质是黄肉果肉主要的呈色组分。差异组分之间存在一定的代谢关联,即紫黄质合成前体的裂解反应及下游异构化反应是造成果肉色泽差异的潜在原因。     

2016年吉林省主栽耐密玉米杂交种综合评价

对吉林省12个中晚熟主栽耐密玉米杂交种进行综合分析与评价。结果表明,参试品种均达到国家一级玉米容重标准,商品品质优良。淀粉含量农华101最低,为淀粉普通型玉米;京科968最高,为75.41%,达到国家高淀粉玉米一级标准;大民899、迪卡519、禾育203、良玉208和禾育35为二级标准;吉农玉833、吉单50、金园15、禾育47和郑单958为三级标准。除了农华101,其他品种子粒是玉米淀粉加工的优质原料,均可以作为高淀粉玉米品种进行种植推广。产量表现为农华101 >吉单50 >京科968 >良玉208 >迪卡519 >大民899 >吉农玉833 >禾育35 >禾育203 >金园15 >郑单958（CK） >禾育47。对品种产量进行方差分析,结果表明,区组间差异不显著,品种间差异显著。     

宽行窄幅错位密播种植方式对夏玉米光合特性及产量的影响

以登海618为试材,常规等行距种植方式为对照,设置不同种植密度、宽窄行种植、行间错位,比较研究宽行窄幅错位密播种植方式对夏玉米光合特性及产量的影响。结果表明,宽行窄幅错位密播种植方式下夏玉米叶面积指数和群体干物质积累量随着种植密度的增加而增加,叶片净光合速率逐渐降低;与对照相比,密度为86 625、101 055株/hm~2时叶片后期衰老缓慢,维持较高净光合速率的时间较长,花后群体干物质积累较多,各器官干物质运转率和对子粒贡献率较高。Richards模型解析表明,宽行窄幅错位密播种植方式下密度为86 625、101 055株/hm~2时达最大灌浆速率的时间较早,起始势和最大灌浆速率较高,子粒灌浆活跃期和灌浆速率最大时的生长量均偏低,植株空秆率较低,分别比对照显著增产5.61%、12.29%。密度为101 055株/hm~2时穗长、穗粗、行粒数、百粒重、穗粒重均比对照偏低,较高的有效收获穗数足以弥补劣势,使子粒获得高产。