Exogenous carbon monoxide attenuates inflammatory responses in the small intestine of septic mice

AIM:To determine whether the carbon monoxide(CO)-releasing molecules(CORM)-liberated CO suppress inflammatory responses in the small intestine of septic mice.METHODS:The C57BL/6 mice(male,n = 36;weight 20 ± 2 g) were assigned to four groups in three respective experiments.Sepsis in mice was induced by cecal ligation and puncture(CLP)(24 h).Tricarbonyldichlororuthenium(Ⅱ) dimer(CORM-2)(8 mg/kg,i.v.) was administrated immediately after induction of CLP.The levels of inflammatory cytokines [interleukin-1(IL-1) and tumor necrosis factor-(TNF-)] in tissue homogenates were measured with enzyme-linked immunosorbent assay.The levels of malondialdehyde(MDA) in the tissues were determined.The levels of nitric oxide(NO) in tissue homogenate were measured and the expression levels of intercellular adhesion molecule 1(ICAM-1) and inducible nitric oxide synthase(iNOS) in the small intestine were also assessed.NO and IL-8 levels in the supernatants were determined after the human adenocarcinoma cell line Caco-2 was stimulated by lipopolysaccharide(LPS)(10 g/mL) for 4 h in vitro.RESULTS:At 24 h after CLP,histological analysis showed that the ileum and jejunum from CLP mice induced severe edema and sloughing of the villous tips,as well as infiltration of inflammatory cells into the mucosa.Semi-quantitative analysis of histological samples of ileum and jejunum showed that granulocyte infiltration in the septic mice was significantly increased compared to that in the sham group.Administration of CORM-2 significantly decreased granulocyte infiltration.At 24 h after CLP,the tissue MDA levels in the midileum and mid-jejunum significantly increased compared to the sham animals(103.68 ± 23.88 nmol/mL vs 39.66 ± 8.23 nmol/mL,89.66 ± 9.98 nmol/mL vs 32.32 ± 7.43 nmol/mL,P < 0.01).In vitro administration of CORM-2,tissue MDA levels were significantly decreased(50.65 ± 11.46 nmol/mL,59.32 ± 6.62 nmol/mL,P < 0.05).Meanwhile,the tissue IL-1 and TNF-levels in the mid-ileum significantly increased compared to the sham animals(6.66 ± 1.09 pg/mL vs 1.67 ± 0.45 pg/mL,19.34 ± 3.99 pg/mL vs 3.98 ± 0.87 pg/mL,P < 0.01).In vitro administration of CORM-2,tissue IL-1 and TNF-levels were significantly decreased(3.87 ± 1.08 pg/mL,10.45 ± 2.48 pg/mL,P < 0.05).The levels of NO in mid-ileum and mid-jejunum tissue homogenate were also decreased(14.69 ± 2.45 nmol/mL vs 24.36 ± 2.97 nmol/mL,18.47 ± 2.47 nmol/mL vs 27.33 ± 3.87 nmol/mL,P < 0.05).The expression of iNOS and ICAM-1 in the mid-ileum of septic mice at 24 h after CLP induction significantly increased compared to the sham animals.In vitro administration of CORM-2,expression of iNOS and ICAM-1 were significantly decreased.In parallel,the levels of NO and IL-8 in the supernatants of Caco-2 stimulated by LPS was markedly decreased in CORM-2-treated Caco-2 cells(2.22 ± 0.12 nmol/mL vs 6.25 ± 1.69 nmol/mL,24.97 ± 3.01 pg/mL vs 49.45 ± 5.11 pg/mL,P < 0.05).CONCLUSION:CORM-released CO attenuates the inflammatory cytokine production(IL-1 and TNF-),and suppress the oxidative stress in the small intestine during sepsis by interfering with protein expression of ICAM-1 and iNOS.

Inhibitory effects of carbon dioxide insufflation on pneumoperitoneum and bowel distension after percutaneous endoscopic gastrostomy

AIM:To evaluate the inhibitory effects of carbon dioxide (CO2) insufflation on pneumoperitoneum and bowel distension after percutaneous endoscopic gastrostomy (PEG).METHODS:A total of 73 consecutive patients who were undergoing PEG were enrolled in our study.After eliminating 13 patients who fitted our exclusion criteria,60 patients were randomly assigned to either CO2 (30 patients) or air insufflation (30 patients) groups.PEG was performed by pull-through technique after threepoint fixation of the gastric wall to the abdominal wall using a gastropexy device.Arterial blood gas analysis was performed immediately before and after the procedure.Abdominal X-ray was performed at 10 min and at 24 h after PEG to assess the extent of bowel distension.Abdominal computed tomography was performed at 24 h after the procedure to detect the presence of pneumoperitoneum.The outcomes of PEG for 7 d postprocedure were also investigated.RESULTS:Among 30 patients each for the air and the CO2 groups,PEG could not be conducted in 2 patients of the CO2 group,thus they were excluded.Analyses of the remaining 58 patients showed that the patients' backgrounds were not significantly different between the two groups.The elevation values of arterial partial pressure of CO2 in the air group and the CO2 group were 2.67 mmHg and 3.32 mmHg,respectively (P = 0.408).The evaluation of bowel distension on abdominal X ray revealed a significant decrease of small bowel distension in the CO2 group compared to the air group (P < 0.001) at 10 min and 24 h after PEG,whereas there was no significant difference in large bowel distension between the two groups.Pneumoperitoneum was observed only in the air group but not in the CO2 group (P = 0.003).There were no obvious differences in the laboratory data and clinical outcomes after PEG between the two groups.CONCLUSION:There was no adverse event associated with CO2 insufflation.CO2 insufflation is considered to be safer and more comfortable for PEG patients because of the lower incidence of pneumoperitoneum and less distension of the small bowel.

Effect of KCI on Growth of Carbon Fibers During Carbonization of Phenolic Resin

Effects of the KCl additions( 1%,3%,5% and7% of the phenolic resin mass) on phase composition and microstructure of the resin carbon and the growth mechanism of carbon fibers were investigated by using commercial liquid phenolic resin as carbon source and micron-scaled KCl as catalyzer,mixing,hexamethylenetetramine solidification treating,carbon-embedded firing at 1 000 ℃ for 3h in order to accelerate the graphitization of phenolic resin during carbonization. The results show that the graphitization degree of resin carbon is improved by catalysis of KCl,numerous carbon fibers with30-200 nm in diameter and 10-20 μm in length and sheet-like carbon in situ grow in resin carbon. The optimal addition of KCl is 5% when lots of carbon fibers can be found in resin carbon,and d002 diffraction peak of graphite appears obviously in the XRD pattern. The growth mechanism of carbon fiber is that the molten KCl at high temperatures absorbs carbonaceous gas from the decomposition of phenolic resin,accelerating the diffusion of solid C atoms in liquid KCl; after the dissolution of C saturates,carbon atoms separate continuously in local parts to form carbon fibers or flakes; meanwhile,the concentration gradient formed by local carbon atoms in the melt offers growth drive for the separation of carbon fibers or flakes on KCl surface.

STUDY ON THE SEQUENCE STRUCTURE OF SBR BY ^(13)C—NMR METHOD Ⅰ. ASSIGNMENT FOR UNSATURAT CARBONS SPECTRA

The sequence structures of emulsion-processed SBR and solution-processed （by lithium catalyst） SBR were investigated by 13C-NMR spectroscopy. Seventeen peaks within unsaturated carbon region were recorded under the adopted experimental conditions. Assignments for these peaks were made by empirical-parameter-evaluation method.

Linear Global Temperature Correlation to Carbon Dioxide Level, Sea Level, and Innovative Solutions to a Projected 6°C Warming by 2100

Too many climate committees, conferences, articles and publications continue to suggest a one and a half (1.5°C) to two degrees (2°C) Celsius as an achievable global limit to climate changes without establishment of any causal link to the proposed anti-warming mechanism. A comprehensive review has found instead that observationally informed projections of climate science underlying climate change offer a different outlook of five to six-degree (5°C - 6°C) increase as “most accurate” with regard to present trends, climate history and models, yielding the most likely outcome for 2100. The most causative triad for the present warming trend from 1950 to the present is identified in this paper: 1) the tripling (3×) of world population;2) the quadrupling (4×) of carbon emissions;and 3) the quintupling (5×) of the world energy consumption. This paper presents a quantitative, linear global temperature correlation to carbon dioxide levels that has great predictive value, a short temporal feedback loop, and the finding that it is also reversible. The Vostok ice core temperature and CO2 values for the past 400,000 years, with past sea level estimates have produced the sufficiently evidential “Hansen’s Graph”. Detailed analysis results in an equation for global average temperature change and an indebted, long-term sea level rise, from even a 20 ppm of CO2 change above 290 ppm, commonly taken as a baseline for levels before 1950. Comparison to the well-known 800,000 year old Dome C ice core is also performed. The best-performing climate change models and observational analysis are seen to project more warming than the average model often relied upon. World atmosphere, temperature, and sea level trends for 2100 and beyond are analyzed. A laboratory experiment proves the dramatic heat-entrapment capability of CO2 compared to pure air, which yields insights into the future global atmospheric system. Policy-relevant climate remediation, including gigaton carbon capture, zero and negative emissions and positive individual action, are reviewed and updated, with recommendations.

中国科技金融与制造业高质量发展的关系研究

科技金融为企业进行技术研发与创新提供资金支持,因而对于制造业高质量发展具有重要影响。同时,它的出现也是制造业发展到一定阶段的结果。因此,制造业的发展质量也会影响科技金融的发展水平。本文在阐述科技金融与制造业高质量发展相互关系的基础上,首先运用熵值法对中国科技金融与制造业高质量发展水平进行评价,然后运用VAR模型对两者之间的相互关系进行研究。结果表明,中国科技金融发展水平与制造业高质量发展水平都在不断提高;科技金融对制造业高质量发展具有一定的显著影响,但是影响程度还需要再提高;而制造业高质量发展对于科技金融没有显著影响。本文提出提高科技金融产品服务能力、扩大其覆盖范围、转变制造业发展模式、拓宽制造业企业融资渠道等对策建议。

全国市场VS区域市场:碳市场有效性的差异、成因及其对策

对碳市场有效性进行测度、把握碳市场运行效率,有利于进一步推动碳交易机制优化和效率提升。本文以全国碳排放权交易市场及8个区域试点碳市场为研究对象,以2021年7月16日至2023年6月16日碳配额成交均价为样本,运用结构突变检验法与重标极差分析法对各个碳市场整体与阶段运行效率进行测度。研究结果表明:全国碳市场整体运行效率偏低,仅第一阶段达到了弱式有效水平;在区域试点碳市场中北京碳市场达到弱式有效,若考虑结构突变点时,则上海、广东、湖北、深圳和重庆碳市场达到阶段性弱式有效。在此基础上,进一步剖析了全国碳市场有效性较低的影响因素,并有针对性地提出对策建议。

基于集对云物元模型的云南省农田碳减排能力综合评估

为探究云南省各市(州)农田生态系统碳减排潜力,基于2011-2020年云南省各市(州)农田碳排放相关面板数据,从能源因素、技术因素与经济因素3个方面建立农田碳减排能力指标体系,使用博弈论组合赋权法确定指标综合权重,引入集对分析,云物元耦合模型与集对分析偏联系数算法,对云南省农田碳减排能力和发展态势进行综合评估分析。评估结果表明:(1)云南省农田碳减排能力空间布局呈现东南强、西南弱,东西中等的格局,其中产业发展格局与区域经济产值是影响农田碳减排能力的主要影响因素;(2)在农田碳减排能力发展态势分析中发现,云南省整体呈现负向发展态势。通过明确云南省农田生态系统碳排放发展现状与识别重点调控地区,因地制宜规划并制定降低农田碳排放的产业布局与耕种管理措施,为云南发展低碳农业提供参考与决策依据。

计及改进生物质燃气和阶梯碳交易的综合能源系统低碳经济调度

为了推动生物质能开发利用并提高综合能源系统运行能效,提出一种含改进生物质燃气BNG(biomass natural gas)和阶梯碳交易的综合能源低碳经济调度模型。首先,构建考虑二阶变压吸附的生物质燃气模型;其次,将生物质燃气耦合电转气和碳捕集系统,从而实现二氧化碳的利用与封存。然后,完善生物质燃气参与后的阶梯碳交易模型,以综合能源系统经济运行成本最小构建目标函数进行优化求解。最后,通过设置不同场景进行分析,验证所提模型能够有效提高系统的经济性以及低碳性。

经济统计与碳中和目标的协同推进策略

文章旨在探讨经济统计在碳中和目标实现过程中的作用,并提出协同推进策略,以实现经济发展与达成碳减排目标的双赢局面。首先,从经济统计与碳中和目标的关系入手,分析二者的定义、作用和关联性。其次,阐述经济统计在实现碳中和目标过程中的具体作用,包括数据收集与分析、监测与评估以及政策制定与决策支持等方面。随后,提出经济统计与碳中和目标的协同推进策略,包括数据整合与标准化、制定有效的政策措施以及提供准确的信息与指导。最后,以国际经验与启示为结语,探讨发达国家和新兴经济体在碳中和目标实现过程中的经验教训,以期为中国经济与碳减排协同推进提供一定的启示与借鉴。

个人碳账户的国内外探索实践

伴随“双碳”目标的稳步实施,消费端的节能降碳更是不容忽视,推出个人碳账户恰逢其时,有利于形成供给侧与需求端双向拉动。近年来,各地政府、银行、企业等主办机构争相涉足消费端碳布局,依托各自资源禀赋,积极就各类场景试水个人碳账户这片“蓝海”,并不断推进个人碳账户迈向全民时代。个人碳账户作为承载个人碳减排记录、核算及价值发现的重要载体,已然成为当下热点。然而,作为新生事物,我国个人碳账户尚处于起步探索阶段,运作实践中仍存在缺乏碳减排量测算标准、平台间互不兼容、信息隐私泄露、权益配套有限,以及商业模式待建立等挑战,面临着“叫好不叫座”的尴尬局面。因此,亟待多维统筹,通过架构严密、设计科学的个人碳账户制度化体系建设,准确计量个人碳减排核算,加快制定“碳资产”变现、交易的市场机制及完善激励政策,推动个人碳账户行稳致远。

个人碳普惠:实践模式、理论溯源及政策思考

随着居民碳排放量的增加,推动公众参与碳减排、形成全社会绿色生活方式,对实现“3060”目标有十分重要的意义。目前,全国多地政府、企业和银行纷纷“试水”个人碳账户,对个人碳普惠的探索持续深入。从主导力量看,个人碳普惠可分为政府主导型、企业主导型和银行主导型;从激励方式看,低碳行为主要有商业激励、政策激励和交易激励三种模式;从实践领域看,碳普惠主要集中在出行、生活、消费、公益等领域。个人碳普惠的理论根源是20世纪末英国提出的个人碳交易设想,其核心在于通过个人碳配额实现全社会整体碳排放量下降,但强制性的个人碳约束实践在欧洲并未收到预期效果,越来越多的个人碳政策开始由碳排放约束转向碳减排激励。目前,我国个人碳普惠发展面临顶层设计缺失、碳普惠市场机制不畅、理论研究不足等问题,严重制约了个人碳减排的价值实现。下一步需要在完善碳普惠制度建设、统一碳普惠平台、优化碳普惠激励及核算等方面加大工作力度。

基于可调热电比和两阶段阶梯式碳交易的多主体综合能源系统低碳经济调度策略

国家“双碳目标”对综合能源系统群的经济性和低碳性提出了更高要求,如何从多层面统筹均衡多主体综合能源系统的经济性和低碳性已成为重要的研究内容。为此,基于运行层面和市场层面提出一种多主体综合能源系统低碳经济运行策略。首先,提出热电比可调的热电联产机组运行方式与控制模型;然后提出基于配额共享机制的内外两阶段阶梯式碳交易模式,引导多主体综合能源系统控制碳排放;最后,以购能成本、碳交易成本、新能源弃用成本和储能电站投资运行成本之和最小为目标函数,通过分段线性化,转化为混合整数线性规划问题进行求解。通过设置对比运行情景,验证所提策略的低碳性、经济性和有效性,并进行灵敏度分析,深度挖掘系统低碳化的内部动力,以期为监管部门决策提供理论参考。

长江口−东海内陆架早期成岩过程及影响因素

边缘海沉积物中的早期成岩作用是影响碳循环和埋藏的重要过程,目前对早期成岩过程及其影响因素的了解还不够深入。于2018年8月在长江口-东海内陆架采集了短柱状沉积物,对间隙水中溶解无机碳(DIC)、溶解无机氮(DIN)、二价铁(Fe ^(2+))、二价锰(Mn^(2+))和硫酸根(SO_(4)^(2-))离子等参数进行了分析,并结合表层沉积物中粒度、比表面积、有机碳及稳定碳同位素组成和底层水环境参数,研究了不同沉积环境下沉积物中的早期成岩过程及其影响因素。结果表明,长江口-东海内陆架泥质区沉积物间隙水中DIC和NH_(4)^(+)的浓度随着深度的增加逐渐增大,且在其中心站位有较高的DIC、NH_(4)^(+)产生通量(分别为4.03 mmol/(m^(2)·d)和0.57 mmol/(m^(2)·d))和SO_(4)^(2-)消耗通量(-4.56 mmol/(m^(2)·d)),沉积物扰动深度为20~40 cm,自长江口向浙闽沿岸逐渐降低;而在砂质区,各溶质在剖面上均无明显变化,且通量较小(DIC:0.60 mmol/(m^(2)·d);NH_(4)^(+):-0.03 mmol/(m^(2)·d);SO_(4)^(2-):-1.05 mmol/(m^(2)·d)),沉积物不存在扰动。扰动层厚度与沉积物间隙水中DIC和NH_(4)^(+)等溶质通量呈正相关,表明沉积物的物理扰动是影响泥质区沉积有机碳再矿化的重要因素。综合上述结果,发现沉积有机碳在泥质区扰动层的降解方式以铁锰还原作用为主,扰动层以下以硫酸盐还原作用为主,而在砂质区的降解主要靠耗氧呼吸作用。本研究丰富了长江口及邻近海域沉积动力过程对早期成岩作用影响的认识,有助于深入理解大河河口及邻近海域有机碳的循环和埋藏。

绿色信贷融资担保:理论逻辑、实践及挑战

融资担保作为重要的增信分险手段,“双碳”目标下在降低银行绿色信贷风险、缓解长尾客群融资困境等方面潜力巨大。近年来,我国各地围绕绿色信贷融资担保机制进行了积极探索,有意识地发挥融资担保在绿色金融市场中的增信分险作用。然而,我国绿色信贷融资担保发展尚处于起步阶段,绿色信贷融资担保整体占比低,在分险模式、融资主体、资金主体等方面具有明显的结构性特征。绿色信贷融资担保面临认定标准不清晰、担保机构能力弱、银行内生动力不强、产品适配性差、市场配套建设不足等问题,在破解“三农”、小微等群体绿色融资难困境,缓释银行绿色金融风险中的作用还较为有限。参考国外部分经济体绿色融资担保经验,建议从标准制定、风险分担激励、规范担保机构发展、完善配套体系建设等层面发力,有效发挥担保机构作为绿色金融的放大器、减压器和助推器作用。

面向双碳目标的典型园区碳排放计算分析

园区是我国城市碳排放的主要场所,厘清园区级碳排放源/碳汇构成是开展园区低碳路径研究的关键。目前,国内外还未发布园区级碳排放计算相关规范或指南,已开展的研究大多针对存量的某一特定类型园区碳排放进行计算分析,未充分考虑新建园区的数据可得性以及计算体系对不同类型园区的适应性问题。因此,开展了计及多类型园区特征的碳排放计算方法研究,从能源活动(覆盖农业、工业、建筑、交通、旅游设施、其他公共基础设施等)、农业生产、工业生产、废弃物处理、绿植碳汇5个维度构建园区级碳排放计算体系,并分别给出数据完备和数据缺失情况下的计算公式。算例表明,所提方法对特色农业型园区、工业制造型园区、商务办公型园区、旅游休闲型园区等多类型园区的碳排放总量计算以及结构分析均适用。

模糊需求下的多中心冷链配送车辆路径问题

针对多配送中心下冷链配送的车辆路径问题,考虑到低碳冷链运输的时效性以及需求不确定性,以碳排放成本、制冷成本、时间惩罚成本等在内的总配送成本最小和客户满意度最大为总目标,建立基于可信性测度理论的模糊机会约束模型。在需求模糊的情况下,利用改进的遗传-大规模邻域搜索算法得到初始计划路线,再通过随机模拟算法得到实际需求,进行路线调整。通过与其他文献求解结果对比,以及分析算例来验证所建算法的有效性和模型的合理性,同时分析模型相关参数对目标值的影响。实验结果表明,嵌入局部搜索的改进遗传算法避免了局部最优,加快了收敛性。而且在需求不明时,多配送中心的冷链配送模式要优于单配送中心。

“双碳”背景下绿色技术创新对制造业企业高质量发展的影响:一个有调节的中介模型

实现“双碳”目标离不开企业绿色技术创新。与传统意义的技术创新相比,绿色技术创新更加注重以低成本的经济活动提升环境质量。基于2010—2021年制造业A股上市公司的面板数据,考察“双碳”背景下绿色技术创新对制造业企业高质量发展的影响。实证分析结果表明:第一,绿色技术创新与制造业企业高质量发展之间存在显著的正相关关系。第二,市场化水平在绿色技术创新赋能制造业企业高质量发展中发挥了中介效应,且绿色技术创新对高市场化水平地区制造业企业高质量发展的促进作用更显著。第三,行业竞争度能够调节绿色技术创新、市场化水平与制造业企业高质量发展之间的关系,且行业竞争度对后半段路径(市场化水平→制造业企业高质量发展)的促进作用更强。

青藏高原冻土土壤呼吸温度敏感性和不同活性有机碳组分研究

对采自青藏高原的4个高海拔冻土样品在5、15、25和35℃4个温度下进行了为期90d的实验室培养。结果发现,随着温度升高,土壤呼吸强度和有机碳累积分解量呈现出不断增大的趋势;在时间变化上,培养初期土壤呼吸强度达到最高值随后不断下降,15d左右以后达到稳定。同样的温度下,土壤呼吸强度呈现如下顺序:沱沱河(草甸沼泽土)>乌丽(高山草甸土)>五道梁(高山草原土)>格尔木(灰棕漠土),但后3个土样之间差别并不显著。通过密度分选、酸水解和氯仿熏蒸方法,分别从物理、化学和生物学的角度对土壤有机碳组分进行划分,同时运用动力学方程分两库和三库对有机碳分解动态进行模拟。结果表明,应用不同实验方法划分的土壤碳组分差异明显,活性有机碳占总有机碳的比例从低到高依次是:微生物量碳占1.26%～10.31%,轻组有机碳占9.13%～20.22%,易氧化有机碳占28.35%～49.35%;分两库和三库拟合土壤不同碳库,二者的活性有机碳占总有机碳比例分别为0.50%～3.65%和0.51%～3.26%,MRT分别为8～56d和8～50d,结果比较接近;此外,应用模型方法所测活性碳比例显著低于实验方法的结果。采用线性、指数和高斯3种模型分析土壤呼吸速率随温度的变化规律,发现均能较好地描述二者关系且以高斯模型为最优,所计算出的Q10值也以高斯模型和培养实验较为契合;Q10值随温度的升高而减小,说明高寒气候条件下的青藏高原冻土对气候变暖的响应将比较敏感。

低碳源城市污水厂碳源优化利用运行模式研究

采用中试规模试验,利用物质平衡分析方法,追踪碳源在各个季节不同工艺条件下的分配和利用情况,以求掌握控制碳源分配的关键性参数,从而建立基于碳源利用的污水厂优化运行模式.在原水年均COD,NH4+-N,TN和TP浓度分别为129,25.6,31.5和3.38mg/L,C/N值和C/P值分别为4.3和39.5的条件下,冬季宜采用倒置A2/O工艺,春季宜选用改良型A2/O工艺,夏季宜选用预缺氧+倒置A2/O工艺,秋季宜选用低氧/常氧交替的预缺氧+倒置A2/O工艺,此时出水带走的COD占系统输入总量的26.1%～29.4%,同化COD比例为27.5%～36.2%,直接好氧氧化的COD比例为4%～22.2%,用于反硝化脱氮的COD比例为14.8%～33.6%,用于聚磷菌超量储磷的COD比例为3.05%～6.9%,出水除总磷指标外,可以达到GB 18918-2002一级B标准.碳源分配的优劣可以作为污水厂工艺筛选和参数调整的重要依据.