COVID TCL:A Joint Metric Loss Function for Diagnosing COVID-19 Patient in the Early and Incubation Period

Convolution Neural Networks(CNN)can quickly diagnose COVID-19 patients by analyzing computed tomography(CT)images of the lung,thereby effectively preventing the spread of COVID-19.However,the existing CNN-based COVID-19 diagnosis models do consider the problem that the lung images of COVID-19 patients in the early stage and incubation period are extremely similar to those of the non-COVID-19 population.Which reduces the model’s classification sensitivity,resulting in a higher probability of the model misdiagnosing COVID-19 patients as non-COVID-19 people.To solve the problem,this paper first attempts to apply triplet loss and center loss to the field of COVID-19 image classification,combining softmax loss to design a jointly supervised metric loss function COVID Triplet-Center Loss(COVID-TCL).Triplet loss can increase inter-class discreteness,and center loss can improve intra-class compactness.Therefore,COVID-TCL can help the CNN-based model to extract more discriminative features and strengthen the diagnostic capacity of COVID-19 patients in the early stage and incubation period.Meanwhile,we use the extreme gradient boosting(XGBoost)as a classifier to design a COVID-19 images classification model of CNN-XGBoost architecture,to further improve the CNN-based model’s classification effect and operation efficiency.The experiment shows that the classification accuracy of the model proposed in this paper is 97.41%,and the sensitivity is 97.61%,which is higher than the other 7 reference models.The COVID-TCL can effectively improve the classification sensitivity of the CNN-based model,the CNN-XGBoost architecture can further improve the CNN-based model’s classification effect.

Non-coding RNA as future target for diagnose and treatment of perineural invasion in cancers

Perineural invasion(PNI),a particularly insidious form of tumor metastasis distinct from hematogenous or lymphatic spread,has the capacity to extend well beyond the primary tumor site,infiltrating distant regions devoid of lymphatic or vascular structures.PNI often heralds a decrease in patient survival rates and is recognized as an indicator of an unfavorable prognosis across a variety of cancers.Despite its clinical significance,the underlying molecular mechanisms of PNI remain elusive,complicating the development of specific and efficacious diagnostic and therapeutic strategies.In the realm of cancer research,non-coding RNAs(ncRNAs)have attracted considerable attention due to their multifaceted roles and cancer-specific expression profiles,positioning them as promising candidates for applications in cancer diagnostics,prognostics,and treatment.Among the various types of ncRNAs,microRNAs(miRNAs),long non-coding RNAs(lncRNAs),and circular RNAs(circRNAs)have emerged as influential players in PNI.Their involvement is increasingly recognized as a contributing factor to tumor progression and therapeutic resistance.Our study synthesizes and explores the diverse functions and mechanisms of ncRNAs in relation to PNI in cancer.This comprehensive review aims to shed light on cutting-edge perspectives that could pave the way for innovative diagnostic and therapeutic approaches to address the challenges posed by PNI in oncology.

Construction of the underlying circRNA-miRNA-mRNA regulatory network and a new diagnostic model in ulcerative colitis by bioinformatics analysis

BACKGROUND Circular RNAs(circRNAs)are involved in the pathogenesis of many diseases through competing endogenous RNA(ceRNA)regulatory mechanisms.AIM To investigate a circRNA-related ceRNA regulatory network and a new predictive model by circRNA to understand the diagnostic mechanism of circRNAs in ulcerative colitis(UC).METHODS We obtained gene expression profiles of circRNAs,miRNAs,and mRNAs in UC from the Gene Expression Omnibus dataset.The circRNA-miRNA-mRNA network was constructed based on circRNA-miRNA and miRNA-mRNA interactions.Functional enrichment analysis was performed to identify the biological mechanisms involved in circRNAs.We identified the most relevant differential circRNAs for diagnosing UC and constructed a new predictive nomogram,whose efficacy was tested with the C-index,receiver operating characteristic curve(ROC),and decision curve analysis(DCA).RESULTS A circRNA-miRNA-mRNA regulatory network was obtained,containing 12 circRNAs,three miRNAs,and 38 mRNAs.Two optimal prognostic-related differentially expressed circRNAs,hsa_circ_0085323 and hsa_circ_0036906,were included to construct a predictive nomogram.The model showed good discrimination,with a C-index of 1(>0.9,high accuracy).ROC and DCA suggested that the nomogram had a beneficial diagnostic ability.CONCLUSION This novel predictive nomogram incorporating hsa_circ_0085323 and hsa_circ_0036906 can be conveniently used to predict the risk of UC.The circRNa-miRNA-mRNA network in UC could be more clinically significant.

Detecting Lumbar Implant and Diagnosing Scoliosis from Vietnamese X-Ray Imaging Using the Pre-Trained API Models and Transfer Learning

With the rapid growth of the autonomous system,deep learning has become integral parts to enumerate applications especially in the case of healthcare systems.Human body vertebrae are the longest and complex parts of the human body.There are numerous kinds of conditions such as scoliosis,vertebra degeneration,and vertebrate disc spacing that are related to the human body vertebrae or spine or backbone.Early detection of these problems is very important otherwise patients will suffer from a disease for a lifetime.In this proposed system,we developed an autonomous system that detects lumbar implants and diagnoses scoliosis from the modified Vietnamese x-ray imaging.We applied two different approaches including pre-trained APIs and transfer learning with their pre-trained models due to the unavailability of sufficient x-ray medical imaging.The results show that transfer learning is suitable for the modified Vietnamese x-ray imaging data as compared to the pre-trained API models.Moreover,we also explored and analyzed four transfer learning models and two pre-trained API models with our datasets in terms of accuracy,sensitivity,and specificity.

Fault Diagnosing System of Steam Generator for Nuclear Power Plant Based on Fuzzy Neural Networks

All kinds of reasons are analysed in theory and a fault repository combined with local expert experiences is establishedaccording to the structure and the operation characteristic of steam generator in this paper. At the same time, Kohonen algo-rithm is used for fault diagnoses system based on fuzzy neural networks. Fuzzy arithmetic is inducted into neural networks tosolve uncertain diagnosis induced by uncertain knowledge. According to its self-association in the course of default diagnosis. thesystem is provided with non-supervise, self-organizing, self-learning, and has strong cluster ability and fast cluster velocity.

Perivascular epithelioid cell tumors of the liver misdiagnosed as hepatocellular carcinoma:Three case reports

BACKGROUND Hepatic perivascular epithelioid cell neoplasms(PEComas)are rare.Diagnostic and treatment experience with hepatic PEComa remains insufficient.CASE SUMMARY Three hepatic PEComa cases are reported in this paper:One case of primary malignant hepatic PEComa,one case of benign hepatic PEComa,and one case of hepatic PEComa with an ovarian mature cystic teratoma.During preoperative imaging and pathological assessment of intraoperative frozen samples,patients were diagnosed with hepatocellular carcinoma(HCC),while postoperative pathology and immunohistochemistry subsequently revealed hepatic PEComa.Patients with hepatic PEComa which is misdiagnosed as HCC often require a wider surgical resection.It is easy to mistake them for distant metastases of hepatic PEComa and misdiagnosed as HCC,especially when it’s combined with tumors in other organs.Three patients eventually underwent partial hepatectomy.After 1-4 years of follow-up,none of the patients experienced recurrence or metastases.CONCLUSION A clear preoperative diagnosis of hepatic PEComa can reduce the scope of resection and prevent unnecessary injuries during surgery.

Diagnosing Dysfunctional Coping in HIV-Infected Persons

Introduction: Dysfunctional coping may negatively affect the effectiveness of highly active anti-retro-viral therapy (HAART) to achieve viral suppression. Despite its negative effects on health outcomes, dysfunctional coping remains undiagnosed and untreated in HIV patients. Therefore, it would seem important to diagnose dysfunctional coping in HIV-patients in order to enable health care providers’ plan and execute intervention and treatment strategies in a population of HIV-patients/HIV-infected persons, to reduce health problems that may be associated with it. Aims/Objectives: 1) To identify elements of dysfunctional coping in HIV-patients. 2) To screen HIV-infective persons for dysfunctional coping. 3) To assess prevalence of dysfunctional coping among HIV-patients. 4) To assess association of duration of HIV-infection (survivability) with dysfunctional coping in HIV-infected persons. Methods: A cross-sectional descriptive study was carried out, to diagnose dysfunctional coping in HIV-infected patients. Subjects were HIV patients receiving HAART at Ahmadu Bello University Teaching Hospital (ABUTH), Zaria, Nigeria. Over 110 HIV-infected persons were screened for dysfunctional coping, using 28-item Brief Cope Questionnaire. Results: After various forms of statistical analyses were performed on the data, results indicate differing prevalent rates for the four key dimensions of dysfunctional coping derived from the Brief-cope questionnaire, used to measure dysfunctional coping in this study;Denial Coping, 68 (61.8 percent), Behavioral Disengagement Coping, 46 (41.8 percent), Substance Use Coping, 24 (21.8 percent), Self-Blame Coping, 61 (55.5 percent);and composite (Integrated/Combined) dysfunctional coping, 49 (44.5 percent). A total prevalence rate of 44.5 percent was reported. Altogether more than 60 percent of the HIV patients screened positive for one dimension of dysfunctional coping or the other. The qui-square analyses revealed an association of denial coping with duration of HIV-infection/survivability. Conclusion/Recommendation: Overall, the study was able to demonstrate that dysfunctional coping was quite common among HIV patients. Dysfunctional coping may be a determinant of health in HIV patients and significantly affect health outcome. It was therefore recommended that interventions focused on coping strategies be integrated into management of HIV patients in order to improve their psychological and physical wellbeing.

Application of ^(18) F-FDG PET/CT Imaging in Diagnosing Bladder Tumor Metastasis Lesions

Bladder tumor is the most common malignant tumor in urinary system and always com- panied with lymph node metastasis. The accurate staging plays a significant role in treatment for bladder tumor and prognostic evaluation, and the distant metastasis predicts worse prognosis. The objective of this study was to assess the clinical significance of 18F-FDG PET/CT imaging in diagnosing bladder tumor metastasis lesions. A retrospective analysis of 60 patients with bladder tumor from October 2008 to May 2010 was done. The patients were stratified based on the imaging technique. Among all 60 cases, besides the primary lesion, 81 suspected lesions were spotted and 73 confirmed as metastasis, including 50 lymph node metastases, 22 distant metastases, and 1 bone metastasis. For PET/CT imaging, its sensitivity was 94.5%, specificity 87.5%, positive predictive value 98.6%, negative predictive value 63.6% and accuracy 93.8% respectively. For CT, its sensitivity was 82.2%, specificity 50%, positive predictive value 93.8%, negative predictive value 23.5% and accuracy 79% respectively. PET/CT im- aging was superior to CT in sensitivity, specificity and accuracy. In conclusion, 18F-FDG PET/CT imaging is more significant in diagnosing bladder tumor metastasis lesions.

Carotid Doppler and transcranial Doppler in diagnosing transient ischemic attack: A healthy control

BACKGROUND： If changes of hemodynamics in internal or external cranial artery and stenosis of atherosclerosis are found eady, patients with transient ischemic attack （TIA） may be treated at an eady phase so as to prevent and decrease the onset of cerebral infarction. Carotid Doppler can analyze carotid canal wall, hemodynamic properties and stenosis, and changes of plaque morphology; however, transcranial Doppler （TCD） can evaluate vascular stenosis and occlusion and judge collateral circulation in cranium through detecting velocity and direction of blood flow. Can the association of them increase the diagnostic rate of TIA？ OB3ECTIVE： To evaluate the effect of the association of carotid Doppler and TCD on TIA in internal carotid artery. DESIGN： Contrast observational study SETTING： Department of Neuroelectrophysiology, Central People＇s Hospital of Huizhou PARTICIPANTS： A total of 54 patients with TIA in internal carotid artery were selected from the Department of Neurology of Huizhou Central People＇s Hospital from May 2004 to June 2005. There were 35 males and 24 females aged 46-81 years. The clinical situation was asthenia of single limb, hemiplegia, anaesthesia of single upper or lower limb, hemianesthesia, sensory disorder and aphasia. The symptoms lasted for less than 2 hours. All cases were diagnosed with CT, and those who had pathological changes of acute cerebral infarction and history of cardiac disease were excluded. Additionally, 50 healthy subjects who were regarded as control group were selected from the Department of Neurology of Huizhou Central People＇s Hospital. There were 30 males and 20 females aged 45-80 years. All subjects were consent. METHODS： HD15000 color Doppler ultrasound （Philips Company, USA） and Muliti-DopX2 TCD （DWL Company, Germany） were used to detect hemodynamics, stenosis and distribution of atherosclerosis in carotid artery and internal carotid artery. Evaluation of marker： Stenosis was calculated by the ratio between the minimal cavity and vascular sectional area at the maximal site of plaque （mild： stenosis 〈 50%; moderate and severe： stenosis t〉 50%）. With TCD, the following results were regarded as stenosis： blood velocity of average envelope 〉 120 cm/s （diagnostic criteria of vascular stenosis of basilar artery： blood velocity of average envelope 〉 80 cm/s）, increase and segmental property of blood flow, and murmu of turbulent flow and vessel. MAIN OUTCOME MEASURES： Positive rate of atherosclerosis and incidence of stenosis with carotid Doppler and TCD. RESULTS： All 54 TIA patients and 50 healthy subjects were involved in the final analysis. ① Results of carotid Doppler： Atherosclerosis and stenosis were obvious in experimental group. Positive rate of atherosclerosis was 85% （46/54） and incidence of stenosis of carotid artery was 41% （22/54）, which were higher than those in control group [52% （26/54）, 41% （22/54）, x^2 = 13.42, 10.90, P 〈 0.01]. ② Results of TCD： In experimental group, positive rate of atherosclerosis at base of skull was 89% （48/54） and incidence of stenosis of internal cranial artery was 48% （26/54）, which were higher than those in control group [62% （31/50）, 0, x^2 = 10.28, 32.00, P 〈 0.01]. Stenosis of artery was mainly involved in middle cerebral artery, initial segment and crotch of carotid artery. CONCLUSION： The association of carotid Doppler and TCD can increase clinically diagnostic rate of TIA and provide bases for apposition and intensity of TIA lesion.

Auditory steady-state evoked response in diagnosing and evaluating hearing in infants

BACKGROUND: Auditory steady-state evoked response (ASSR) is one of the new objective electrophysiological methods to test hearing in infants. It can provide a reliable and complete audiogram with specific frequency to help the hearing diagnosis and rehabilitation of hearing and languaging following auditory screening. OBJECTIVE: To compare the response threshold of ASSR with auditory threshold of visual reinforcement audiometry (VRA) in infants failed in the hearing screening for investigating their hearing loss. DESIGN: A comparative observation. SETTINGS: Maternal and child health care hospitals of Guangdong province, Shunde city, Nanhai city and Huadu district. PARTICIPANTS: Totally 321 infants of 0-3 years undergoing ASSR test were selected from the Hearing Center of Guangdong Maternal and Child Health Care Hospital from January 2002 to December 2004. Informed consents were obtained from their guardians. There were 193 cases (60.2%) of 0-6 months, 31 cases (9.7%) of 7-12 months, 17 cases (5.3%) of 13-18 months, 14 cases (4.4%) of 19-24 months, 33 cases of 25-30 months, and 33 cases (10.2%) of 31-36 months. METHODS: ① The 321 infants failed in the hearing screening were tested under sleeping status, the ranges of response threshold distribution in ASSR of different frequencies were analyzed in each age group. ② The infants above 2 years old were also tested with VRA, and their response thresholds were compared between VRA and ASSR. ③ Evaluative standards: The response threshold was < 30 dB for normal hearing, 31-50 dB for mild hearing loss, 51-70 dB for moderate hearing loss, 71-90 dB for severe hearing loss, and > 91 dB for extremely severe hearing loss. MAIN OUTCOME MEASURES: ① ASSR results of the infants failed in the screening; ② Proportion of cases of each response threshold in each age group; ③ Comparison of ASSR response thresholds and VRA auditory thresholds in the infants of 2-3 years old. RESULTS: ①The response threshold was < 30 dB in 47.4% of the 321 infants failed in the initial hearing screening and secondary screening after 42 days. ② Severe to extremely severe hearing loss was detected in only 16 cases (8.3%) of the 193 infants of 0-6 months, in 9 cases (27.3%) of the 33 infants of 25-30 months, and 13 cases (39.4%) of the 33 infants of 31-36 months. Of the 193 infants of 0-6 months old who failed in the initial screening and the second screening after 42 days, the ASSR auditory threshold was < 30 dB in 97 cases (50.26%), 31-50 dB in 63 cases (32.6%), 51-70 dB in 17 cases (8.8%), 71-90 dB in 7 cases (3.6%), and > 91 dB in 9 cases (4.7%). ③ Among the 321 infants failed in the screening, the auditory threshold in the 6 age groups was < 30 dB in 47.4%, 31-50 dB in 27.1%, 51-70 dB in 8.4%, 71-90 dB in 6.2%, and > 91 dB in 10.9%. ④ The difference between ASSR response threshold and VRA auditory thresholds was 6-18 dB in the normal hearing group, mild and moderate hearing loss groups, and there was high correlation between them. The difference of ASSR and VRA thresholds was less than 5 dB between extremely severe and severe hearing loss groups, 5-13 dB between extremely severe and moderate-to-severe hearing loss groups (P < 0.05), and there was no significant differences between severe and moderate-to-severe hearing loss groups (P > 0.05). CONCLUSION: ① The hearing was normal in about half of the infants, although they failed in the primary screening and secondary screening. ② The proportion of the severity of hearing loss was increased along with aging. ③ Mild and moderate hearing losses are dominant in infants. ④ ASSR is reliable to evaluate the hearing of infants.

Teaching Strategy on Diagnosing and Removing Automobile’s Failure

:This article first analyzes the problems existing in the teaching about diagnosing and removing automobile’s failure,and then discusses some specific teaching strategies on diagnosing and removing automobile’s failure to provide some effective reference for the related staff.

ZIZ-2 Vibration monitoring and diagnosing system for turbine generator units

ZJZ-2 system has the following functions: (1) Real-time on-line sampling and FFT analysis (32 channel); (2) Data aquisition, analysis and storage during start-up and shut-down; (3) Alarming, emergency recognition and fault retrieval; (4) Data aquisition, analysis and storage during daily operation; (5) Recall of historic data; (6) Output of routine reports and tables; (7) Analysis of vibration behaviour: Bode plot, polar plot, spectrum, cascade, waveform, shaft orbit, trend, etc;

Prediction System for Diagnosis and Detection of Coronavirus Disease-2019(COVID-19):A Fuzzy-Soft Expert System

In early December 2019,a new virus named“2019 novel coronavirus(2019-nCoV)”appeared in Wuhan,China.The disease quickly spread worldwide,resulting in the COVID-19 pandemic.In the currentwork,we will propose a novel fuzzy softmodal(i.e.,fuzzy-soft expert system)for early detection of COVID-19.Themain construction of the fuzzy-soft expert systemconsists of five portions.The exploratory study includes sixty patients(i.e.,fortymales and twenty females)with symptoms similar to COVID-19 in(Nanjing Chest Hospital,Department of Respiratory,China).The proposed fuzzy-soft expert systemdepended on five symptoms of COVID-19(i.e.,shortness of breath,sore throat,cough,fever,and age).We will use the algorithm proposed by Kong et al.to detect these patients who may suffer from COVID-19.In this way,the present system is beneficial to help the physician decide if there is any patient who has COVID-19 or not.Finally,we present the comparison between the present system and the fuzzy expert system.

A Validated Model for the Imaging Diagnosis of Cystic Lung Disease

Rationale and Objectives: Cystic lung disease may be accurately diagnosed by imaging interpretation of specialist radiologists, without other information. We hypothesized that with minimal training non-specialists could perform similarly to specialist physicians in the diagnosis of cystic lung disease. Methods: 72 cystic lung disease cases and 25 cystic lung disease mimics were obtained from three sources: 1) a prospective acquired diffuse lung disease registry, 2) a retrospective search of medical records and 3) teaching files. Cases were anonymized, randomized and interpreted by 7 diffuse lung disease specialists and 15 non-specialist radiologists and pulmonologists. Clinical information other than age and sex was not provided. Prior to interpretation, non-specialists viewed a short PDF training document explaining cystic lung disease interpretation. Results: Correct first choice diagnosis of 85%-88% may be achieved by high-performing specialist readers and 71%-80% by non-specialists and lower-performing specialists, with mean accuracies in the diagnosis of LAM (91%, p Conclusion: With specific but limited training, non-specialist physicians can diagnose cystic lung diseases from CT appearance alone with similar accuracy to specialists, correctly identifying approximately 75% of cases.

Infrastructure of Synchrotronic Biosensor Based on Semiconductor Device Fabrication for Tracking, Monitoring, Imaging, Measuring, Diagnosing and Detecting Cancer Cells

Copper Zinc Antimony Sulfide(CZAS)is derived from Copper Antimony Sulfide(CAS),a famatinite class of compound.In the current paper,the first step for using Copper,Zinc,Antimony and Sulfide as materials in manufacturing synchrotronic biosensor-namely increasing the sensitivity of biosensor through creating Copper Zinc Antimony Sulfide,CZAS(Cu1.18Zn0.40Sb1.90S7.2)semiconductor and using it instead of Copper Tin Sulfide,CTS(Cu2SnS3)for tracking,monitoring,imaging,measuring,diagnosing and detecting cancer cells,is evaluated.Further,optimization of tris(2,2'-bipyridyl)ruthenium(II)(Ru(bpy)32+)concentrations and Copper Zinc Antimony Sulfide,CZAS(Cu1.18Zn0.40Sb1.90S7.2)semiconductor as two main and effective materials in the intensity of synchrotron for tracking,monitoring,imaging,measuring,diagnosing and detecting cancer cells are considered so that the highest sensitivity obtains.In this regard,various concentrations of two materials were prepared and photon emission was investigated in the absence of cancer cells.On the other hand,ccancer diagnosis requires the analysis of images and attributes as well as collecting many clinical and mammography variables.In diagnosis of cancer,it is important to determine whether a tumor is benign or malignant.The information about cancer risk prediction along with the type of tumor are crucial for patients and effective medical decision making.An ideal diagnostic system could effectively distinguish between benign and malignant cells;however,such a system has not been created yet.In this study,a model is developed to improve the prediction probability of cancer.It is necessary to have such a prediction model as the survival probability of cancer is high when patients are diagnosed at early stages.

随机离散事件系统基于动态观测的安全诊断研究

现有随机离散事件系统研究大都是假设事件的可观测性是固定不变的,而许多实际应用系统中事件的可观测性往往与系统所处的状态有关。为此,本文提出一种动态观测下随机离散事件系统安全可诊断方法。引入一种动态观测,使每一个状态都有各自独立的可观事件;对动态观测下随机离散事件系统安全可诊断性进行形式化;推导出一个基于安全诊断器的动态观测下随机离散事件系统安全可诊断性的充分必要条件,实现动态观测下随机离散事件系统的故障安全诊断。

动词实现类型的甄别与鉴定

Talmy在实现事件研究中,提出了固有、完全、隐含、未然实现的实现动词分类,但其本质还未被充分认识,而且缺乏实证数据支持。鉴于此,本文(a)针对固有实现动词不编码目标的问题,参照实现事件结构重新假设动词的实现类型及其区分;(b)实证固有与完全实现动词具有同等蕴涵目标实现的能力和独立激活框架事件的能力,前者可容纳颗粒度丰富的卫星语素,而后者只能容纳单一语义的格式塔卫星语素;(c)发现动词激活框架事件的能力与其编码目标实现的能力正相关;(d)基于被验证的假设和发现设计了甄别方法和步骤;(e)设计的两步诊断法能准确、有效区分动词实现类型。

国家高性能计算环境运行状态诊断系统

【目的】本文介绍了一种在大规模分布式运行环境中建立运行状态诊断系统的方法。【应用背景】为保障高性能计算环境的稳定运行,分析日志等环境数据是一种获取环境状态侧写和发现异常的重要途经。然而分析结果通常是文本和数字,对运维人员来讲缺乏直观印象,不利于快速理解。【方法】我们建设了国家高性能计算环境运行状态诊断系统,它是一种对于目标计算环境的运行状态进行量化和可视化评判的系统,通过对于目标环境的信息收集、整理,进行不同角度的分项分析。【结果】各分析结果被集成为统一的环境运行状态分值,并采用可视化方法将其立体地表现出来,以便相关运维人员能够直观地获取环境信息和快速定位问题。【结论】整个环节绝大部分处理分析工作是由程序自动完成,环境运行状态诊断系统极大减少了人工操作量,为运维工作起到有效的支撑作用。

钍基熔盐反应堆内化学研究进展和展望

熔盐反应堆是第四代核能系统中唯一使用液态燃料的反应堆,在钍基熔盐反应堆研制和运行中有许多直接与化学相关的关键问题,堪比“化学堆”。于是,因熔盐反应堆研发和运行的需要诞生了放射化学在裂变能利用中的一门新分支学科——熔盐反应堆化学。本实验室利用加速器驱动的中子源和γ能谱分析技术开展了钍基熔盐反应堆化学研究。本文介绍了钍铀转换中间核素~(233)Pa和裂变产物~(131)I及~(95)Nb在熔盐反应堆模拟燃料盐中分布和行为的研究进展。基于对美国橡树岭国家实验室(ORNL)的熔盐反应堆实验装置运行中的燃料盐、锕系元素和裂变产物等相关若干问题分析,提出了在钍基熔盐反应堆框架内熔盐反应堆内化学方面应该进一步开展的研究内容,包括钍基熔盐反应堆运行的化学检测和诊断、影响熔盐氧化还原电势的因素、熔盐氧化还原电势检测的新技术等。熔盐反应堆化学研究的进一步深入将拓展熔盐反应堆化学实践和理论,使钍基熔盐反应堆化学水平提升到新高度,为未来钍基熔盐反应堆高效安全运行提供科学技术方面的支撑和保障。

初诊肺结核患者肠道菌群改变及其与耐多药的临床关系分析

目的:观察初诊肺结核患者肠道菌群改变,并分析其与耐多药的临床关系。方法:选取2021年6月至2023年5月本院收治的初诊肺结核患者347例,纳入肺结核组。另选取同期于本院体检的健康受试者347例,纳入健康组。比较两组肠道菌群属水平的相对丰度及肠道菌群Observed species指数、Shannon指数;肺结核组患者治疗2个月后,根据结核分枝杆菌(MTB)是否耐多药将肺结核组分为耐多药组、非耐多药组;比较耐多药组、非耐多药组一般资料及肠道菌群属水平的相对丰度;采用Logistic回归模型分析初诊肺结核患者耐多药的影响因素。结果:与健康组比较,肺结核组丁酸单胞菌属、类杆菌属、乳杆菌属、双歧杆菌属、布劳特菌属、梭状芽孢杆菌属的相对丰度及Observed species指数、Shannon指数降低(P<0.05),肠球菌属、粪球菌属、多尔菌属、志贺菌属、小杆菌属、韦荣球菌属、瘤胃球菌属的相对丰度升高(P<0.05);初诊肺结核患者耐多药率23.08%;与非耐多药组比较,耐多药组双歧杆菌属的相对丰度及Observed species指数、Shannon指数降低(P<0.05);Logistic回归模型分析显示,初中及以下文化程度(OR=2.678,95%CI:1.309~5.476)、慢性阻塞性肺疾病(COPD)(OR=3.931,95%CI:1.514~10.212)、结核病接触史(OR=2.494,95%CI:1.364~4.562)、肺结核空洞病灶数量(OR=2.776,95%CI:1.872~4.116)、治疗过程中断(OR=2.450,95%CI:1.306~4.596)、双歧杆菌属相对丰度(OR=0.393,95%CI:0.268~0.576)和Shannon指数(OR=0.463,95%CI:0.302~0.712)是初诊肺结核患者耐多药的影响因素(P<0.05)。结论:初诊肺结核患者肠道菌群平衡失调,初中及以下文化程度、COPD、结核病接触史、肺结核空洞病灶数量、治疗过程中断是其耐多药的危险因素,双歧杆菌属相对丰度、Shannon指数是其保护因素。