Improved elastase production by Bacillus sp. EL31410—further optimization and kinetics studies of culture medium for batch fermentation

An efficient culture medium producing a bacterial elastase with high yields was developed further following preliminary studies by means of response surface method. Central composite design (CCD) and response surface method-ology were applied to optimize the medium constituents. A central composite design was used to explain the combined effect of three medium constituents, viz, glucose, K2HPO4, MgSO47H2O. The strain produced more elastase in the completely optimized medium, as compared with the partially optimized medium. The fitted model of the second model, as per RSM, showed that glucose was 7.4 g/100 ml, casein 1.13 g/100 ml, corn steep flour 0.616 g/100 ml, K2HPO4 0.206 g/100 ml and MgSO47H2O 0.034 g/100 ml. The fermentation kinetics of these two culture media in the flask experiments were analyzed. It was found that the highest elastase productivity occurred at 54 hours. Higher glucose concentration had inhibitory effect on elastase production. At the same time, we observed that the glucose consumption rate was slow in the completely optimized medium, which can explain the lag period of the highest elastase production. Some metal ions and surfactant additives also affected elastase production and cell growth.

A comprehensive study of long-term skeletal changes after spinal cord injury in adult rats

Spinal cord injury（SCI）-induced bone loss represents the most severe osteoporosis with no effective treatment.Past animal studies have focused primarily on long bones at the acute stage using adolescent rodents. To mimic chronic SCI in human patients, we performed a comprehensive analysis of long-term structural and mechanical changes in axial and appendicular bones in adult rats after SCI. In this experiment, 4-month-old Fischer 344 male rats received a clinically relevant T13 contusion injury. Sixteen weeks later, sublesional femurs, tibiae,and L4 vertebrae, supralesional humeri, and blood were collected from these rats and additional non-surgery rats for micro-computed tomography（m CT）, micro-finite element, histology, and serum biochemical analyses.At trabecular sites, extreme losses of bone structure and mechanical competence were detected in the metaphysis of sublesional long bones after SCI, while the subchondral part of the same bones showed much milder damage. Marked reductions in bone mass and strength were also observed in sublesional L4 vertebrae but not in supralesional humeri. At cortical sites, SCI induced structural and strength damage in both sub- and supralesional long bones. These changes were accompanied by diminished osteoblast number and activity and increased osteoclast number and activity. Taken together, our study revealed site-specific effects of SCI on bone and demonstrated sustained inhibition of bone formation and elevation of bone resorption at the chronic stage of SCI.

Long-Term Study of Lake Evaporation and Evaluation of Seven Estimation Methods: Results from Dickie Lake, South-Central Ontario, Canada

Establishing satisfactory calculation methods of lake evaporation has been crucial for research and manage-ment of water resources and ecosystems. A 30 year dataset from Dickie Lake, south-central Ontario, Canada added to the limited long-term studies on lake evaporation. Evaporation during ice-free season was calcu-lated separately using seven evaporation methods, based on field meteorology, hydrology and lake water temperature data. Actual evaporation determined during a portion of a year was estimated using a lake en-ergy budget model, and the estimation was used as reference evaporation for evaluation of the seven methods. The deviation of method-induced evaporation from the reference evaporation was compared among the seven methods, and a performance rank was proposed based on the root mean squared deviation and coeffi-cient of efficiency. As for the whole ice-free season (roughly May to November), the water balance was the best method, followed by Makkink, DeBruin-Kejiman, Penman, Priestley-Taylor, Hamon, and Jensen-Haise methods. As for shorter duration (a week to a month), the DeBruin-Kejiman was the best method, followed by Penman, Priestley-Taylor, Makkink, Hamon, Jensen-Haise, and water balance method. Annual and sea-sonal changes of energy budget terms and the compensation function of lake heat storage in evaporation flux were also analyzed.

A comparative study of pancreatic endocrine function and related metabolism after long-term survival between the patients with combined kidneypancreas transplantation vs those with combined en bloc ' liver-pancreas transplantation

Objective To compare the effects of combined en bloc liver - pancreas transplantation ( LPT) with portal vein drainage and simultaneous combined kidney - pancreas transplantation ( KPT) with systemic venous drainage on the pancreatic endocrine function and related me-

Numerical study of forward smoldering combustionof polyurethane foam

A two-dimensional and two-phase numerical model is presented for the smolder propagation in a horizontal polyurethane foam. The chemical processes considered include endothermic pyrolysis and exotherrnic oxidation degradation of polyurethane foam and exothermic oxidation of char. The governing equations are discretized in space using the finite element method and solved by the software package FEMLAB. Predicted profiles of solid temperature as well as evolutions of solid compositions （including foam, char and ash） are presented at an airflow velocity of 0. 28 cm/s. The computed average smoldering velocity is 0. 021 4 cm/s, and the average maximum temperature is 644. 67 K. Based on the evolutions of solid compositions, the packed bed can be obviously divided into four zones： unreacted zone, fuel pyrolysis and oxidation zone, char oxidation zone and fuel burned-out zone. Simultaneously, the effects of inlet air velocity and fuel properties （including thermal conductivity, specific heat, density and pore diameter） are studied on the smoldering propagation. The results show that the smoldering velocity and temperature have a roughly linear increase with increasing inlet air velocity; the fuel density is the most important factor in determining smoldering propagation; radiation has a non-negligible role on the smoldering velocity for larger pore diameters of porous material. The computational results are compared with the experimental data and a general agreement is reached.

基于价值共创视角的大中型抽水蓄能电站建设管理模式创新研究

“十四五”期间,我国抽水蓄能产业步入高质量发展阶段,大中型抽水蓄能电站建设亟需进行建设管理模式创新。本研究基于价值共创理论,将大中型抽水蓄能电站建设管理创新路径解构为价值主张、价值创造、价值传递、价值获取四大模块,选取梅州抽水蓄能电站为研究案例,通过实证资料编码分析其创新举措。研究揭示大中型抽水蓄能电站建设管理模式创新要素关系网络和革新方向,为其管理模式创新提供参考建议。

变几何涡轮燃气轮机总体性能研究

为深入了解变几何涡轮对燃气轮机的总体性能影响机理,通过部件法对燃气轮机进行建模,然后分别改变高压涡轮、中压涡轮和动力涡轮的第一级导向器喉道面积,在不考虑导叶两端调节机构和导叶间隙等对涡轮效率影响情况下,对燃气轮机总体性能的变化情况进行了系统地分析,并得出各截面的总温与总压变化情况。结果表明:在采用保持高压涡轮入口总温恒定的控制规律时,增大燃气轮机的高压涡轮流通能力,燃气轮机输出轴功率与耗油率均不断增加,高压涡轮流通能力增加10%,输出轴功率与耗油率分别上升2.83%与1.13%;增大燃气轮机的中压涡轮流通能力,导致燃气轮机输出轴功率降低,耗油率上升,中压涡轮流通能力增加10%,输出轴功率降低9.96%,耗油率上升3.63%;动力涡轮流通能力增加,燃气轮机输出轴功率先上升,后有小幅下降,耗油率增大,动力涡轮流通能力变化量从0增加到10%,输出轴功率降低0.05%,耗油率增加2.01%。

长沙某地区同轴套管式中深层地热试验井换热及恢复性能研究

在能源结构亟待转型背景下,中深层地热资源展现出了极大优势和开发潜力,但地热资源受地域差异性影响较大,实测研究相对匮乏,给产业规模化应用带来了阻力。本文针对中南地区中深层地热实测研究空缺现实情况,首次基于长沙地区中深层地热试验井,通过分布式光纤实时监测和换热试验测试,探索该区中深层地热资源情况、换热性能和地温恢复能力。试验结果表明:该区中深层地热资源具有良好开发潜力,井底2611m温度达82.8℃,全井平均地温梯度为2.47℃/100m,试验期稳定换热功率达到534.7kW;循环流量与地埋管换热功率呈正相关,与工质温升呈负相关;井温恢复呈现初期快后期慢特点,前24h完成50%的温度恢复量,纵向深度呈现深处快浅处慢的情形,井底温度完全恢复时,300m深处温度仅恢复至初始工况74.6%;与北方高异常区资源禀赋对比,长沙地区中深层地热条件仍处于劣势。

选煤厂重介旋流器参数优化与工艺研究

重介旋流器是选煤工业中的关键设备,用于分离煤与岩石。研究选煤厂重介旋流器的参数优化与工艺流程,通过实验设计和数值模拟相结合的方法,系统分析不同参数对分离效率的影响,同时探讨操作条件如温度和压强变化对重介旋流器性能的影响,从而为实际生产中的参数调整和过程控制提供科学依据。通过工艺优化,降低了能源消耗,提高了煤炭质量和选煤厂的经济效益。

Long-term results of laparoscopic fenestration for patients with congenital liver cysts

BACKGROUND: The feasibility and immediate outcome of laparoscopic fenestration for patients with congenital liver cysts have been generally recognized. The aim of the present study was to assess the long-term results after laparoscopic fenestration. METHODS: A retrospective study was performed on 44 patients with congenital liver cysts who had undergone laparoscopic fenestration between June 1998 and December 2004. Among them, 30 were women and 14 men, aged 57 years on average (range 18-76 years). While 14 patients had solitary cysts, 20 had multiple cysts, and 10 had polycystic liver disease. The results of laparoscopic fenestration, including mortality, morbidity, mean postoperative hospital stay, and recurrences of cysts were evaluated. RESULTS: There was no perioperative death and the morbidity rate was 11% (5/44). All complications were treated conservatively. The mean postoperative hospital stay was 4 days. A mean follow-up of 57 months showed that the rates of cyst recurrence and symptom recurrence were 9% and 4.5%, respectively. CONCLUSION: Laparoscopic fenestration as a feasible and safe treatment procedure for patients with congenital liver cysts can yield very good long-term results.

Studies on Barriers for Promotion of Clean Technology in SMEs of China

After more than 10 years efforts on awareness raising and promotion, the concept of cleaner production (CP) has been adopting as a strategic approach to balance economic benefits and environmental protection for China’s industries. However, it is also found that clean technology is difficult to be adopted and implemented in Chinese Small and Medium-sized Enterprises (SMEs) because of certain barriers. This paper investigates these barriers among three stakeholders--governments, enterprises and experts. The Analytic Hierarchy Process (AHP) was employed to prioritize the relative importance of the twenty fine-selected barriers, which were classified into four barrier categories. The findings reveal that the exterior barriers of policy and financial barriers should be stressed rather than the inner barriers of technical and managerial barriers, although they are also very important. Absence of incentives on economic policies, lax enforcement of environmental regulations and high initial capital cost were the most important barriers to adoption of Clean Technologies (CT) in China.

Long-term results of an anatomically implanted hip arthroplasty with a short stem prosthesis (MiniHip^(TM))

AIM To evaluate the clinical and radiological outcome nineand ten years after short-stemmed, bone preserving and anatomical hip arthroplasty with the MiniHip^(TM) system. METHODS In a prospective study, 186 patients underwent hip arthroplasty with a partial neck preserving short stem(MiniHip^(TM), Corin). Elderly patients were not excluded from this study, thus the mean age at the time of surgery was 59.3 years(range 32 to 82 years). Surgery and the follow-up assessments were performed at two Centers. Up until now, the mean follow-up was 112.5 ± 8.2 mo. The Oxford Hip Score(OHS) and the Hip Dysfunction Osteoarthritis and Outcome Score(HOOS) was assessed pre-and each year after surgery. The clinical follow-up was accompanied by standardized a.p. and axial radiological examinations. Periprosthetic lucencies, hypertrophies within the Gruen zones one to fourteen were assessed. A subsidence of the stem was investigated according to Morray and heterotopic ossifications were assessed according to Brooker.RESULTS The OHS and HOOS improved from 18 ± 3.3 to 46 ± 2.0 and from 30 ± 8.3 to 95 ± 4.6 points, P < 0.001 respectively. There were no differences regarding age, etiology, friction pairings, etc.,(P > 0.05). Two stems were revised due to a symptomatic subsidence four and twelve months postoperatively. Thus, the survivorship for aseptic loosening at nine to ten years was 98.66%. Including one stem revision due to a symptomatic exostosis, bursitis and thigh pain as well as one revision because of a septic stem loosening, the overall survival for the stem with revision for any reason was 97.32%. Besides one asymptomatic patient, radiological signs of a proximal stress-shielding, such as bone resorptions within the proximal Gruen zones, were not noticed. Findings suggesting a distal loading, e.g., bony hypertrophies or bone appositions of more than 2 mm, were also not detected. CONCLUSION Regarding these first long-term results on the MiniHip^(TM), the implant performed exceedingly well with a high rate of survivorship for aseptic loosening. Our radiological results within the Gruen zones support the design rationale of the Minihip to provide a reliable metaphyseal anchoring with the expected proximal, more physiological load transfer. This might minimize or exclude a stress shielding which might be associated with thigh pain, proximal bone loss and an increased risk of aseptic loosening. The MiniHip^(TM) is a reliable partial-neck retaining prosthesis with good a clinical long-term outcome in younger as well as elderly patients.

Survivors of COVID-19 exhibit altered amplitudes of low frequency fluctuation in the brain: a resting-state functional magnetic resonance imaging study at 1-year follow-up

Although some short-term follow-up studies have found that individuals recovering from coronavirus disease 2019(COVID-19)exhibit anxiety,depression,and altered brain microstructure,their long-term physical problems,neuropsychiatric sequelae,and changes in brain function remain unknown.This observational cohort study collected 1-year follow-up data from 22 patients who had been hospitalized with COVID-19(8 males and 11 females,aged 54.2±8.7 years).Fatigue and myalgia were persistent symptoms at the 1-year follow-up.The resting state functional magnetic resonance imaging revealed that compared with 29 healthy controls(7 males and 18 females,aged 50.5±11.6 years),COVID-19 survivors had greatly increased amplitude of low-frequency fluctuation(ALFF)values in the left precentral gyrus,middle frontal gyrus,inferior frontal gyrus of operculum,inferior frontal gyrus of triangle,insula,hippocampus,parahippocampal gyrus,fusiform gyrus,postcentral gyrus,inferior parietal angular gyrus,supramarginal gyrus,angular gyrus,thalamus,middle temporal gyrus,inferior temporal gyrus,caudate,and putamen.ALFF values in the left caudate of the COVID-19 survivors were positively correlated with their Athens Insomnia Scale scores,and those in the left precentral gyrus were positively correlated with neutrophil count during hospitalization.The long-term follow-up results suggest that the ALFF in brain regions related to mood and sleep regulation were altered in COVID-19 survivors.This can help us understand the neurobiological mechanisms of COVID-19-related neuropsychiatric sequelae.This study was approved by the Ethics Committee of the Second Xiangya Hospital of Central South University(approval No.2020 S004)on March 19,2020.

Predictors of Discontinuation of Antipsychotic Therapy in Patients with Acute Schizophrenia: A 1-Year Observational Study with More Than 1000 Patients

Discontinuation of antipsychotic therapy has been a significant clinical issue among patients with schizophrenia, since the patients who discontinued antipsychotic treatment showed worse clinical and functional outcomes, and higher risks of relapse of schizophrenia symptoms and hospitalization. We conducted a post-hoc analysis of a post-marketing research with a 12-month follow-up period to identify the predictors for discontinuation of antipsychotic monotherapy in Japan. This is a prospective, naturalistic multicenter observational study, designed to evaluate the discontinuation rates of olanzapine monotherapy and non-olanzapine antipsychotic monotherapy in Japanese adult patients with acute schizophrenia. Patients were treatment-naive, or had switched from other antipsychotics or from poly-pharmacotherapy to oral antipsychotic monotherapy. We analyzed the correlation of discontinuation of antipsychotic monotherapy with baseline characteristics of patients. A total of 1089 patients (578 patients treated with olanzapine and 511 with non-olanzapine antipsychotics) were eligible for analysis. By the end of the 12-month study period, 614 patients (56.4%) discontinued antipsychotic therapy. Multivariate logistic regression analyses indicated significantly lower discontinuation rates in all patients treated with antipsychotics: older age (Odds ratio [OR], 0.871;95% confidence interval [CI], 0.797 to 0.953;p = 0.003), outpatient status (OR, 0.508;95% CI, 0.383 to 0.675;p < 0.001), prior use of antipsychotics (OR, 0.693;95% CI, 0.516 to 0.930;p = 0.015), and olanzapine group showed lower discontinuation rate than that of non-olanzapine group (OR, 1.416;95% CI, 1.086 to 1.846;p = 0.010). The present study indicated that the outpatient status, older age, and prior use of antipsychotics have better adherence to antipsychotic treatment. In addition to these factors, use of anti-parkinson agents showed lower discontinuation rates in the olanzapine monotherapy group.

Direct carboxylation of thiophene with CO_(2) in the solvent-free carboxylate-carbonate molten medium:Experimental and mechanistic insights

A feasible synthesis route is devised for realizing direct carboxylation of thiophene and CO_(2) in a relatively mild solvent-free carboxylate-assisted carbonate(semi)molten medium.The effects of reaction factors on product yield are investigated,and the phase behavior analysis of the reaction medium is detected through the thermal characterization techniques.Product yield varies with the alternative carboxylate co-salts,which is attributed to the difference in deprotonation capacity caused by the base effect within the system.Besides,the detailed mechanism of this carbonate-promoted carboxylation reaction is studied,including two consecutive steps of the formation of carbanion through breaking the C-H bond(s)via the carbonate and the nucleophile attacking the weak electrophile CO_(2) to form C-C bond(s).The activation energy barrier in C-H activation step is higher than the following CO_(2) insertion step whether for the formation of the mono-and/or di-carboxylate,which is in good agreement with that of kinetic isotope effect(KIE)experiments,indicating that the C-H deprotonation is slow and the forming presumed carbanion reacts rapidly with CO_(2).Both the activation energy barriers in deprotonation steps are the minimal for the cesium cluster system since there have the weak the cesium Cs-heteroatom S(thiophene)and Cs-the broken proton interactions compared to the K2CO3 system,which is likely to enhance the acidity of C-H bond,lowering the C-H activation barrier.Besides,these mechanistic insights are further assessed by investigating base and C-H substrate effects via replacing Cs2CO3 with K2CO3 and furoate(la)with thiophene monocarboxylate(1b)or benzoate(1c).

微调平衡法治疗Ⅲ、Ⅳ期非小细胞肺癌队列研究

目的:观察微调平衡治癌法对于Ⅲ、Ⅳ期非小细胞肺癌患者生活质量、客观疗效、肿瘤指标、疾病无进展生存期等方面的影响。方法:采用前瞻性队列研究方法,选取符合纳入标准的Ⅲ、Ⅳ期非小细胞肺癌50例患者为研究对象,根据是否同时使用中医药治疗(微调三号方、微调四方号口服)分为治疗组、对照组各25例,观察两组的卡氏功能状态(KPS)评分、临床常见症状改善情况、近期客观疗效、疾病无进展生存期等。结果:治疗后,治疗组临床症状积分及KPS评分较对照组明显下降(P﹤0.01);治疗组疾病控制率(CR+PR+SD)为86.36%,高于对照组的57.14%(P﹤0.05);治疗组中位无进展生存期为9.2个月,长于对照组6.3个月(P﹤0.05)。结论:微调平衡治癌法治疗Ⅲ、Ⅳ期非小细胞肺癌,可以改善患者体力状况,减轻临床症状,延长无进展生存期。

国家审计推动中小银行防范化解风险的路径

党的二十大报告指出防范化解金融风险须解决许多重大问题,要守住不发生系统性风险的底线。中小银行是我国金融体系的重要组成部分,由于股权结构、内控能力、区域金融生态环境等多种因素影响,在内外部环境深刻变化的背景下,各类风险加速暴露。推动防范和化解中小银行风险,对守住不发生系统性金融风险的底线具有重要意义。本文系统梳理了国家审计开展中小银行审计的历史沿革,对国家审计在推动防范化解中小银行风险过程中的主要优势进行深入剖析。在此基础上,从宏观、中观和微观三个层面,研究探索新时代国家审计推动中小银行防范化解风险的实施路径。

三曲分酵操作法在浓香型白酒生产中的工艺研究

阐述了以冀酿2号高粱为原料,以三曲分酵的方式酿造浓香型白酒的生产工艺:冬季采用低温大曲为糖化发酵剂,春秋季节采用中温大曲,夏季采用高温大曲入窖发酵,收到预期效果。不仅解决了浓香型白酒在冬季升温缓慢的弊端,也打破了夏季压排停产的惯例。

河南省科技型中小企业融资影响因素研究

近年来,河南省科技型中小企业发展迅速,但由于其自身的特点,在成长的同时也面临诸多风险,而对于中小企业而言,融资是企业发展过程中不可避免的行为。选取2018-2021年在全国股份转让系统挂牌上市的55家河南省科技型中小型企业为样本,构建模型进行回归分析,对企业融资影响因素进行实证分析与探讨,结果表明,企业规模、总资产收益率、主营业务增长率等与企业融资能力正相关,企业未分配利润比例、速动比率与企业融资能力负相关。

“双减”背景下学科类中小培训机构转型路径探究——以河南省中部XX县XX书房为例

“双减”政策出台后,学科类培训面临政府政策的从严监管和治理,学科类培训行业巨头率先调整业务,开始转向教育培训的其他赛道。学科类中小培训机构面临资金匮乏、人才流失,综合竞争力不足等转型困境。为应对转型中的困境,学科类中小培训机构要通过厘清政策导向、找准目标市场、细化主营业务、重组师资团队以及优化招生策略等方式,实现成功转型。培训机构成功转型为书房,能产生一定的实际价值,如为学生终身学习奠定基础、补充学校教育的不足、解决部分就业问题。