油气管道风险评估质量评价技术

油气管道完整性管理的本质特征是基于风险程度的事故预先管控模式。因此,风险评估结果的准确性将直接影响到油气管道完整性管理决策的科学性。为此,在分析风险评估对管道完整性管理的决策影响和事故热点辨识工程意义的基础上,提出了评价油气管道风险评估质量的技术思路。首先从人因因素、物因因素、工程因素和管理因素4个方面探讨了影响油气管道风险评估质量的客观外因,然后重点研究了油气管道风险评估质量的评价原理及其可以采用的相关评价方法,选取了评价方法简单、易于操作的指标体系法来进行质量评价,结合工程实际设计出了油气管道风险评估质量评价的基本流程(质量评价实施前准备阶段、实施工作阶段、实施完成阶段)以及相应的评价指标体系;最后通过案例分析验证了油气管道风险评估质量评价技术的操作实用性。该研究从一个全新的角度揭示了提高油气管道风险评估结果准确性的技术途径,对推进我国油气管道完整性管理的技术进步具有一定的参考意义。

Autophagy and ethanol-induced liver injury

The majority of ethanol metabolism occurs in the liver. Consequently, this organ sustains the greatest damage from ethanol abuse. Ethanol consumption disturbs the delicate balance of protein homeostasis in the liver, causing intracellular protein accumulation due to a disruption of hepatic protein catabolism. Evidence indicates that ethanol or its metabolism impairs trafficking events in the liver, including the process of macroautophagy, which is the engulfment and degradation of cytoplasmic constituents by the lysosomal system. Autophagy is an essential, ongoing cellular process that is highly regulated by nutrients, endocrine factors and signaling pathways. A great number of the genes and gene products that govern the autophagic response have been characterized and the major metabolic and signaling pathways that activate or suppress autophagy have been identified. This review describes the process of autophagy, its regulation and the possible mechanisms by which ethanol disrupts the process of autophagic degradation. The implications of autophagic suppression are discussed in relation to the pathogenesis of alcohol-induced liver injury.

Leafy head formation of the progenies of transgenic plants of Chinese cabbage with exogenous auxin genes

The experiment was performed to evaluate the progenies of plant lines transgenic for auxin synthesis genes derived from Ri T-DNA. Four lines of the transgenic plants were selfcrossed and the foreign auxin genes in plants of T5 generation were confirmed by Southern hybridization. Two lines, D1232 and D1653, showed earlier folding of expanding leaves than untransformed line and therefore had early initiation of leaf y head. Leaf cuttings derived from plant of transgenic line D1653 produced more adventitious roots than the control whereas the cuttings from folding leaves had much more roots than rosette leaves at folding stage, and the cuttings from head leaves had more roots than rosette leaves at heading stage. It is demonstrated that early folding of transgenic leaf may be caused by the relatively higher concentration of auxin. These plant lines with auxin transgenes can be used for the study of hormonal regulation in differentiation and development of plant organs nd for the breeding of new varietywith rapid growth trait.

Water Quality, Climatic and Plant Traits as Predictors on Abundance of Insects in Paddy Field, Tanjung Karang, Selangor, Malaysia

The abundance of beneficial insects in the paddy field can be influenced by the abundance of insect pests, water parameters, climatic factors and plant traits. This study was conducted to determine effects of water parameters, climatic factors and plant traits on abundant insects. Findings of the studies showed that there were significant correlations between all beneficial insects in paddy field and water parameters tested, namely, water temperature, salinity, turbidity, pH, dissolved oxygen, biological oxygen demand, chemical oxygen demand, ammonia and total suspended solids. Moreover, the selected water parameters of water temperature, dissolved oxygen, biological oxygen demand and chemical oxygen demand were good predictors for abundant beneficial insects in paddy field at Sungai Burong, specifically for insects of sub-orders Anisoptera and Zygoptera, and insects from families Gerridae and Coccinellidae. The plant height, insect pest, temperature, rainfall and humidity were found to be good predictors on the abundance of beneficial insects; nevertheless, the R2 value of multiple regression models was relatively low due to significant relationship between water parameters and insects. Consideration factors of water parameters, climatic factors and plant traits were strongly correlated with those parameters and abundance of insects in the paddy field at Sungai Burong, Tanjung Karang, Selangor.

A GATA-type transcription factor AcAREB for nitrogen metabolism is involved in regulation of cephalosporin biosynthesis in Acremonium chrysogenum

In filamentous fungi,nitrogen metabolism is repressed by GATA-type zinc finger transcription factors.Nitrogen metabolite repression has been found to affect antibiotic production,but the mechanism is still poorly understood.AcareB,encoding a homologue of fungal GATA-type regulatory protein,was cloned from Acremonium chrysogenum.Gene disruption and genetic complementation demonstrated that AcareB plays a key role in utilization of ammonium,glutamine and urea.In addition,significant reduction of cephalosporin production in the AcareB disruption mutant indicated that AcareB is important for cephalosporin production.In consistence with it,the transcriptional level of cephalosporin biosynthetic genes was significantly decreased in the AcareB disruption mutant.Electrophoretic mobility shift assay showed that AcAREB directly bound to the intergenic regions of pcbAB-pcbC,cefD1-cefD2 and cefEF-cefG.Sequence analysis showed that all the AcAREB binding sites contained the consensus GATA elements.AcareB is negatively autoregulated during cephalosporin production.Moreover,another GATA zinc-finger protein encoded by AcareA positively regulates the transcription of AcareB.However,AcareB does not regulate the transcription of AcareA.These results indicated that AcAREB plays an important role in both regulation of nitrogen metabolism and cephalosporin production in A.chrysogenum.

Environmental factors determining growth of salamander larvae： A field study

Larval growth and survival of organisms are strongly influenced by abiotic and biotic factors, as demonstrated by ex- perimental studies performed under controlled laboratory or semi-natural conditions. Even if they have many advantages, ex- periments cannot cover the full complexity of natural conditions and field studies are needed for a better understanding of how environmental variation determines growth and development rate. Fire salamander Salamandra salamandra females give birth to larvae in a variety of habitats, both epigean and subterranean. In caves, salamander larvae successfully grow and metamorphose, but their growth is more than three times longer than in epigean streams and factors determining these differences require inves- tigation. We performed a field study to understand the factors related to the growth of fire salamander larvae in different envi- ronmental conditions, evaluating the relationship between environmental features and larval growth and differences between caves and epigean spring habitats. Both caves and epigean larvae successfully grew. Capture-mark-recapture allowed to individu- ally track individuals along their whole development, and measure their performance. Growth rate was significantly affected by environmental variables： larvae grew faster in environments with abundant invertebrates and few conspeciflcs. Taking into ac- count the effect of environmental variables, larval growth was significantly lower in caves. Food availability plays a different ef- fect in the two environments. Larval growth was positively related to the availability of invertebrates in epigean sites only. The development rate of hypogeous populations of salamanders is slower because of multiple parameters, but biotic factors play a much stronger role than the abiotic ones

Dropout reasons and associated factors with active dropout in Chinese healthy participants of bioequivalence studies

Maintaining participants in a trial ultimately without dropout helps keep a study on track,saving time,money,and resources.Since 2015,extensive bioequivalence(BE)studies have been carried out in China,while no research about dropout in healthy volunteers has been reported yet.In this retrospective study,1078 healthy volunteers participating in 18 BE studies from March 2016 to February 2019 in one Chinese hospital were included.Information about the healthy participants and BE studies was recorded for analysis.In terms of the dropout reason,poor compliance,adverse event(AE),and loss of follow-up were found to be the three leading causes of dropout,accounting for 78.7%of all dropouts.In terms of associated factors with active dropout,smoking habit(OR=5.790,P<0.001)was significantly associated with increased risk of active dropout,while older age(OR=0.940,P=0.042)and AE except for SAE(OR=0.321,P=0.004)were significantly associated with a decreased risk of active dropout.Strengthening the education on younger participants and participants with a smoking habit,as well as emphasizing the possible adverse reactions and potential risks,might be strategies to reduce active dropout in healthy participants.

The integration characteristics of the exogenous growth hormone gene in a transgenic common carp(Cyprinus carpio L.) with fast-growth performance

The genetic stability and expression efficiency of exogenous genes in transgenic animals are closely related to integration site and copy number. In our laboratory, by transgenic manipulation and subsequent test crosses, we established an ‘‘all-fish'' growth hormone(GH)transgenic common carp family that exhibits fast growth.In this present study, genome walking, real-time quantitative polymerase chain reaction, and fluorescence in situ hybridization techniques were applied to identify the integration characteristics of the exogenous grass carp GH gene in the transgenic common carp. The exogenous GH genes, in the form of two complete and one incomplete tandem repeats, were found to have integrated into an ATrich region near the end of a chromosome pair. We hypothesize that the high efficiency of exogenous GH gene expression might be due to the low copy number in the genome and the AT-rich integration site.