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关键词： 基质金属蛋白酶-9   脂联素   老年   肺叶切除术   术后谵妄  

摘要： 目的评价老年肺叶切除术患者围术期血清基质金属蛋白酶-9(matrix metalloprote-inase-9,MMP-9)及脂联素(adiponectin,ADP)浓度与术后谵妄(postoperative delirium, POD)的相关性。方法选择择期全麻下行肺叶切除术老年患者73例,男38例,女35例,年龄65～80岁,BMI<24 kg/m^2,ASAⅠ或Ⅱ级,术后24、48和72 h采用中文版意识模糊评估量表评估认知功能,根据患者是否发生POD将患者分为两组:POD组和非POD组。于麻醉诱导前5 min(T_0)、气管拔管即刻(T_1)、术后24 h(T_2)、术后48 h(T_3)和术后72 h(T_4)采集静脉血样,测定血清MMP-9及ADP浓度。结果 13例患者发生POD,发生率为17.8%。与T_0时比较,T_1—T_4时POD组血清MMP-9浓度明显升高,血清ADP浓度明显降低(P<0.05);T_1时非POD组MMP-9浓度明显升高,血清ADP浓度明显降低(P<0.05)。T_1—T_4时POD组血清MMP-9浓度明显高于,ADP浓度明显低于非POD组(P<0.05)。结论围术期血清MMP-9浓度升高与ADP浓度下降可能参与老年肺叶切除术患者POD发生的病理生理过程。

关键词： 膜生物反应器   应用   污水处理   废水排放量   出水水质   用地面积   膜污染  

摘要： 近年来,随着废水排放量的飞速增长,膜生物反应器以其出水水质高、用地面积小、易于控制等优点得到迅速的推广。本文综述了膜生物反应器的类型、研究历程、应用以及膜生物反应器的优缺点,介绍了膜生物反应器存在的最大问题——即膜污染以及膜污染的防治,希望给膜生物反应器的进一步研究应用提供参考。

关键词： 膜   生物反应器   乡镇   生活污水   工程实例  

摘要： 以双膜内循环生物反应器(DMBR)处理广西壮族自治区某镇生活污水为例,介绍了DMBR处理工艺及其在工程中的应用。应用结果表明,经DMBR处理后的出水水质符合《城镇污水处理厂污染物排放标准》(GB 18918-2002)中的一级A标准要求,DMBR处理工艺具有占地面积小、成本低、处理高效、自动化监控、运行稳定可靠、污泥产生量少的特点,是小型污水处理工程的理想工艺选择,可供乡镇生活污水处理工程参考和借鉴。

关键词： Resuscitation-promoting factor   Membrane bioreactor   Phenol degradation at high salinity   Resuscitation and stimulation   Bacterial population shifts  

摘要： Enhancement of bacterial activity in membrane bioreactor (MBR) is crucial to overcome the low efficiency of biological process for treating phenolic wastewater with high salinity. It is predicted that resuscitation promoting factor (Rpf) from Micrococcus luteus may improve the degradative performance of bacterial populations. In this study, a control MBR (c-MBR) and a treatment MBR (t-MBR) with Rpf addition were operated for assessing the influences of Rpf. The potential bacterial populations in response to Rpf addition were investigated by both culture-dependent and culture-independent techniques. Results showed that Rpf significantly enhanced phenol removal under high salinity stress. In the MBR system, a higher efficiency for phenol removal in the effluent was observed in t-MBR compared to that in c-MBR (nearly zero versus 221-272 mg/L) under phenol concentration of 1800 mg/L and 30 g/L NaCl in the influent. Batch tests further demonstrated that, at the initial phenol concentration of 1500 mg/L and 60 g/L NaCl, sludge from t-MBR could achieve almost 100% phenol removal within 100 h, while it was only 54.7% for the sludge from c-MBR. High-throughput 16S rRNA analysis indicated that the genus Rhizobium in Alphaproteobacteria was greatly enriched in the t-MBR. The genus Pseudomonas in Gammaproteobacteria was identified as the dominant resuscitated bacteria. These findings suggested that Rpf-responsive bacterial species belonging to Alphaproteobacteria and Gammaproteobacteria were key populations contributed to better phenol-degrading capabilities under high salinity condition.

关键词： 麻竹   枝条扦插   基质   激素浓度   交互作用  

摘要： 为提高麻竹Dendrocalamus latiflorus枝条扦插成活率与生根率,筛选出最佳配方及处理方法,选择1年生麻竹枝条为材料,采用从基质、激素种类及浓度三因素析因设计,研究各因素及其相互作用对麻竹扦插生长的影响,并运用隶属函数法综合评价了育苗效果。结果表明:1)3个主因素中,激素种类对扦插生根影响最大,各指标均达到显著水平;2)泥炭对扦插苗地上的生长指标影响最大,新梢率、新梢数和叶数达显著水平;3)细沙作为基质可以显著提高麻竹枝条扦插生根率,扦插成活率达62.92%;4)两因素交互作用中,激素×浓度的交互作用对扦插生根的影响最大,愈伤率、腐烂率、平均根长、总根数、根系直径等指标均达极显著水平;5)激素种类×激素浓度对扦插地上指标影响最大,叶面积达极显著水平,新梢数达显著水平;6)三因素交互作用中,仅愈伤率和腐烂率达到极显著水平。由此可见,泥炭显著提高扦插生根率,NAA扦插效果最好,激素浓度处于40～80 mg/L时扦插苗各指标最佳;泥炭+ABT+80 mg/L为最佳处理组合。

关键词： 光生物反应器   超滤膜   海水养殖废水   微藻   营养盐去除  

摘要： 以海水养殖废水为培养基质,在膜-光生物反应器(membrane photobioreactor,MPBR)中进行微藻的连续进出水培养,对微藻的生长情况和废水中氮磷营养盐的去除效果进行了研究。首先,将小球藻和衣藻接种于海水养殖废水中进行批次培养,两种微藻均表现出对海水养殖废水较好的适应性,实现了较快生长,比生长速率分别为0.29和0.26 d^(-1)。之后,将小球藻和衣藻分别接种到水力停留时间为1.0 d的MPBR中进行为期32 d的连续进出水培养。小球藻和衣藻的生物量生产速率分别为37.9和32.4 mg·L^(-1)·d^(-1),分别是批次培养中微藻指数生长阶段生物量生产速率的3.4倍和3.6倍。同时MPBR也实现了对海水养殖废水中氮磷营养盐的高效去除,小球藻MPBR和衣藻MPBR在稳定运行阶段对溶解性无机氮(DIN)的平均去除率分别达到93.9%和93.6%,其对溶解性无机磷(DIP)的平均去除率分别达到98.8%和99.0%。可见采用膜法连续培养方法既实现了光生物反应器内微藻的高效培养,同时也实现了对进水中氮磷营养盐的高效去除,另外废水在处理过程中的停留时间相比于传统批次培养得到了极大的缩短,这些都将有利于促进微藻培养方法在水产养殖业的废水处理和循环使用中发挥更大的作用。

关键词： membrane bioreactor   moving bed biofilm reactor   bacterial ecology   bacterial community structures   oligotypes distribution  

摘要： A bench-scale bioreactor was operated under two different technologies of membrane bioreactor and hybrid moving bed bioreactor-membrane bioreactor at hydraulic retention time 6-16h, sludge retention time 6-24 days, and mixed liquor suspended solids 3400-7800mgL(-1). Analyses of their bacterial community structures showed marked differences between the two technologies for global communities but not for dominant phylotypes, and the domination of different bacterial phylotypes for the different operational conditions. Tetrasphaera genus was ubiquitous (1.1%-19.2% relative abundance) in both bioprocesses. Fodinibacter (0.04%-7.75%) was found to positively correlate with other dominant phylotypes, highlighting the relevance of Intrasporangiaceae family in membrane-based technologies. Oligotypes distribution of dominant phylotypes showed that certain strains were favored at all operational conditions. Linkage with operational conditions determined that the presence/absence of carriers deeply impacted the relative abundance of dominant phylotypes. The results are relevant to discern the effect of operational conditions over bacterial communities in membrane-based technologies. (c) 2018 American Institute of Chemical Engineers AIChE J, 65: 536-548, 2019

关键词： cake deposition   reversible and irreversible fouling   MBR   physical cleaning   pore blocking   RIS model  

摘要： The cake layer deposited on the membrane modules of membrane bioreactors (MBRs), especially under a submerged configuration, represents a relevant and fundamental mechanism deeply influencing the development of membrane fouling. It negatively affects the total resistance to filtration, while exerting a positive effect as a "pre-filter" promoting the "dynamic membrane" that protects the physical membrane from internal fouling. These two opposite phenomena should be properly managed, where the submerged membranes are usually subjected to a periodical cake layer removal through ordinary (permeate backwashing and air scouring) and/or irregular cleaning actions (manual physical cleaning). In this context, the physical removal of the cake layer is needed to maintain the design filtration characteristics. Nevertheless, the proper evaluation of the effect of physical cleaning operations is still contradictory and under discussion, referring in particular to the correct evaluation of fouling mechanisms. The aim of the present work was to summarize the different aspects that influence the fouling investigations, based on simple models for the evaluation of the resistance to filtration due to the cake layer, through physical cleaning operations.

关键词： Epigenetic erasing   High plasticity   Micro-bioreactor   PTFE   SMAD2   TAZ  

摘要： Phenotype definition is driven by epigenetic mechanisms as well as directly influenced by the cell microenvironment and by biophysical signals deriving from the extracellular matrix. The possibility to interact with the epigenetic signature of an adult mature cell, reversing its differentiated state and inducing a short transient high plasticity window, was previously demonstrated. In parallel, in vitro studies have shown that 3D culture systems, mimicking cell native tissue, exert significant effects on cell behavior and functions. Here we report the production of PTFE micro-bioreactors for long-term culture of epigenetically derived high plasticity cells. The system promotes 3D cell rearrangement, global DNA demethylation and elevated transcription of pluripotency markers, that is dependent on WW domain containing transcription regulator 1 (TAZ) nuclear accumulation and SMAD family member 2 (SMAD2) co-shuttling. Our findings demonstrate that the use of 3D culture strategies greatly improves the induction and maintenance of a high plasticity state.

关键词： Scale-down   Kinetic model   Corynebacteriwn glutamicum  

摘要： In this study, the impact of dissolved oxygen concentrations oscillations on Corynebacteriwn glutamicum 2262 Delta idhA growth was studied experimentally and modeled. Aiming at this, a dedicated two-compartment scale down set-up composed of two interconnected aerobic/anaerobic stirred tank bioreactors was used. The mean residence time of bacteria in each compartment was modified by adapting circulation rates and culture volumes in each bioreactor and the resulting temporal ratio of aeration was calculated. The five growth kinetics were then modeled using an original kinetic model coupling Monod growth modeling and the Residence Time Distributions. Our study showed that the microbial growth rate and macroscopic yields were clearly linked to the temporal ratio of aeration, allowing the definition of simple but robust law for process scale-up purpose. It was also revealed that the model proposed precisely agreed with the experimental growth data, whatever the fractions of aeration time imposed experimentally.