Colonic lesion expert system. Performance evaluation

A computer-based expert system for diagnosing colonic sections as normal, adenoma or adenocarcinoma is described, along with an evaluation of its performance. On the basis of its knowledge base, consisting of the values of diagnostic clues and their associated certainty factors for the possible diagnoses, the system will suggest the diagnosis for new cases presented to it. Using the data provided for 16 diagnostic clues, the system arrived at correct diagnoses for all cases of normal colon, for 49 of 50 cases of adenoma and for 48 of 49 cases of adenocarcinoma. Sample outputs from the expert system are presented and discussed, and the effects of possible alterations in the data base are considered.     

Evaluation of models capacity to predict size spectra parameters in ecosystems under stress

Size spectra are important indicators of biomass distribution, for fundamental understanding as well as for application in management. While many size spectra models have been developed, it is unclear how response to stress varies across models and in comparison to data. In the present study, we therefor collected papers on empirical size spectra in stressed aquatic ecosystems and compared the results to theoretical models’ predictions from literature. A general decrease of the slope, as suggested by most of the studied models, is supported by the data found. The investigated empirical studies revealed a strong trend for the slope: 40 out of 57 studies reported a decrease with stress. Deviations from the linear model increased in 10 out of 20 cases and the intercept became larger in 25 out of 43 cases. The data concerning specific impact drivers is generally consistent and supportive of current expert opinions. Our results support that an integration of deviation from the linear model and intercept in the size spectra models could provide better coupling between modeling and field surveys for some stressors.     

城市生态系统研究中遥感技术的应用

本文提出并论证了城市生态系统研究与遥感的总体方案及主要研究方向和研究方法。可以认为,用遥感技术作为获取数据的手段,用动态大系统理论分析数据,并借助于专家系统和地理信息系统处理和管理数据,可以解决城市生态系统研究中全方位信息的收集和巨大信息量的处理两大难题;通过引入中间变量把非空间直接可测变量表述为空间直接可测量的函数,从而在专家系统和地理信息系统的支持下扩大遥感技术的应用领域。     

Frequency of congenital malformations and chromosomal disorders in Bacau and Vaslui counties (Romania)

This paper presents the state of genetic health of the human populations in two Romanian counties, Bacau and Vaslui, as they are different in area, number of inhabitants, level of economic and social development, etc. The data presented in this paper is from the Public Health Directions of the two counties, reflecting the situation recorded during 2006–2013. In the 8 years study, 1894 cases of congenital and chromosomal disorders were recorded in the newborns from the populations in the two counties. The identified cases were distributed based on years, categories of disorders and sexes. The average frequency of congenital disorders in the two populations over the investigated period was about 1.65 in Bacau county and 1.83% in Vaslui counties. In the population of Bacau county, these disorders affect in the same number in both the sexes (49.62% female cases and 50.38% male cases), while in Vaslui, the male cases are more than the females (53.92 and 46.08%, respectively). The main congenital disorders observed were: cardiovascular system anomalies, musculoskeletal system, urogenital system, etc. During the investigation period, in the human population of Bacau county, 97 cases of newborns with chromosomal disorders were diagnosed (0.16% of the living newborns), while in Vaslui county there were 106 cases (0.26% of the living newborns). Among these disorders, the Down’s syndrome was the most frequent one, representing 83.5 and 85.8% of cases in the population of Bacau county, and Vaslui counties.     

Interpretations of and management actions following electrocardiograms in symptomatic patients in primary care: a retrospective dossier study

Background

The electrocardiogram (ECG) has become a popular tool in primary care. The clinical value of the ECG depends on the appropriateness of the indication and the interpretation skills of the general practitioner (GP).

Objectives

To describe the use of electrocardiography in primary care and to assess the performance of GPs in interpreting ECGs and making subsequent management decisions.

Methods

Three hundred ECGs, recorded during daily practice in symptomatic patients by 14 GPs who regularly perform electrocardiography, were selected. Corresponding data of the indications, interpretations and subsequent management actions were extracted from the associated medical records. A panel consisting of an expert GP and a cardiologist reviewed the ECGs and specified their agreement with the findings and actions of the study GPs.

Results

The most common indications were suspicion of a rhythm abnormality (43.7%), ischaemic heart disease (42.7%) and patient reassurance (14.3%). The study GPs interpreted 53.3% of the ECGs as showing no (new or acute) abnormality, whereas supraventricular rhythm disorders (12.3%), conduction disorders (7.7%) and repolarisation disorders (7.0%) were the most frequently reported pathological findings. Overall, the expert panel disagreed with the interpretations of the study GPs in 16.2% of cases, and with the GPs’ management actions in 11.7%. Learning goals for GPs performing electrocardiography could be formulated for acute coronary syndrome, rhythm disorders, pulmonary embolism, reassurance, left ventricular hypertrophy and premature ventricular complexes.

Conclusion

GPs who feel competent in electrocardiography performed well in the opinion of the expert panel. We formulated various learning objectives for GPs performing electrocardiography.

     

The PARTICLE expert system for tumor grading by automated image analysis

While automated microscopic image analysis of histologic sections has been helpful in objectivizing histologic tumor grading and investigating the relationships between grading and prognosis, expert systems have the potential of linking image analysis and other data for statistical analysis and application to a wider range of tumors. One such expert system is PARTICLE, whose development was based on many years of experience in resolving histologic problems by image analysis. This paper discusses the philosophy of expert system for tumor grading and describes its implementation in the PARTICLE system. The system's structure, operations and applications are briefly presented. PARTICLE is essentially based on the evaluation of karyometric data.     

A knowledge base for predicting protein localization sites in eukaryotic cells

To automate examination of massive amounts of sequence data for biological function, it is important to computerize interpretation based on empirical knowledge of sequence-function relationships. For this purpose, we have been constructing a knowledge base by organizing various experimental and computational observations as a collection of if-then rules. Here we report an expert system, which utilizes this knowledge base, for predicting localization sites of proteins only from the information on the amino acid sequence and the source origin. We collected data for 401 eukaryotic proteins with known localization sites (subcellular and extracellular) and divided them into training data and testing data. Fourteen localization sites were distinguished for animal cells and 17 for plant cells. When sorting signals were not well characterized experimentally, various sequence features were computationally derived from the training data. It was found that 66% of the training data and 59% of the testing data were correctly predicted by our expert system. This artificial intelligence approach is powerful and flexible enough to be used in genome analyses.     

Regulation of dopamine system responsivity and its adaptive and pathological response to stress

Although, historically, the norepinephrine system has attracted the majority of attention in the study of the stress response, the dopamine system has also been consistently implicated. It has long been established that stress plays a crucial role in the pathogenesis of psychiatric disorders. However, the neurobiological mechanisms that mediate the stress response and its effect in psychiatric diseases are not well understood. The dopamine system can play distinct roles in stress and psychiatric disorders. It is hypothesized that, even though the dopamine (DA) system forms the basis for a number of psychiatric disorders, the pathology is likely to originate in the afferent structures that are inducing dysregulation of the DA system. This review explores the current knowledge of afferent modulation of the stress/DA circuitry, and presents recent data focusing on the effect of stress on the DA system and its relevance to psychiatric disorders.     

Telepathology: a tool to aid in diagnosis and quality assurance in cervicovaginal cytology

Telepathology: a tool to aid in diagnosis and quality assurance in cenicovaginal cytology
The purpose of this study is to evaluate the use of a Teletransmission System with regard to quality of diagnosis and screening so as to establish its potential role in gynaecological cytology. Three aspects of its use in cytopathology have been considered: diagnosis, training, and quality control. The circumstances in which the system may be used for diagnosis, together with its advantages and disadvantages, are examined and discussed. In general, the costbenefit in diagnostic use related to the experience of both the expert and the peripheral pathologist. The system may also contribute to training and quality assessment, particularly if combined with other automated services, such as an image data bank.     

On-line control of feeding of medium components to attain high cell density

On line control coupled with an expert system was constructed for the control of a fed-batch culture with the aim of achieving a high cell density. During the cultivation, the expert system could monitor the extents of sufficiencies in the amounts of chemical elements in the medium every 10 min, and suggest a modification to the feeding control policy if the amount of a particular component was inadequate for cell growth. However, we often encounter such a kind of cultivations in which some particular carbon source such as glucose and ethanol should be controlled at low concentration in many culture processes, because the excess feeding might cause the growth inhibition by its own accumulation in the culture broth, or the biproduct accumulation like as lactate or acetate, unsuitable substances for smoothed growth. In this study, we developed an online control system based on production rules which managed the glucose feed rate from DO signal. The online control was carried out by the control computer connected with the other computer for expert system, because a relatively long time (several minutes) was needed for the inference of the expert system and the influence of the starvation of carbon source on the cell growth is not negligible even in several minutes. The on-line control system with expert system was applied to the production of cell mass of E. coli W3110 and the final cell concentration reached 137 g-dry cell weight/l.     

Colonic lesion expert system. Evaluation of sensitivity

In a previous study, an expert system using visually assessed diagnostic clues for diagnosing colonic tissue as normal, adenoma or adenocarcinoma arrived at diagnoses agreeing with the evaluation by pathologists ("correct diagnoses") for all 49 cases of normal colon, for 49 of 50 cases of adenoma and for 48 of 49 cases of adenocarcinoma. The present study examined the robustness and sensitivity of the expert system to changes in the knowledge base, to changes in criteria specified by the user and to missing information. Alternative rules for combining certainty factors are discussed.     

Center for the evaluation of risks to human reproduction--the first five years

The National Toxicology Program (NTP) Center for the Evaluation of Risks to Human Reproduction (NTP-CERHR) was established by the NTP and the National Institute of Environmental Health Sciences (NIEHS) in 1998 to address the impact of chemical exposures on human reproductive and developmental health and to serve as an environmental and reproductive health resource for government agencies and the general public. The purpose of this report is to provide an overview of the Center activities and a summary of NTP conclusions on chemicals evaluated during this time period. CERHR evaluations involve the critical review of reproductive, developmental, and other relevant toxicity data by independent panels of scientists. The products of these evaluations are expert panel reports. The public has opportunities to provide oral comments at the panel meeting and written comments on draft and final expert panel reports. The NTP evaluates these comments, the conclusions of the expert panel, and any new data not available at the time of the panel meeting, and prepares an NTP brief that describes in plain language the NTP's conclusions on the reproductive and developmental hazard from specified chemical exposures. The NTP brief, expert panel report, and public comments comprise the NTP monograph on the chemical. Monographs are sent to federal regulatory agencies, the NTP Executive Committee, and the NTP Board of Scientific Counselors, and are publicly available. Over the last five years, CERHR conducted expert panel evaluations on 14 chemicals. At this time, 13 panel reports have been published and 12 NTP-CERHR monographs have been issued. Additionally, CERHR conducted a 2-day workshop on the role of thyroid hormones in reproductive and developmental health.     

医学实验诊断数据的自动分析模型及应用

本文利用实验诊断原始数据获得对应的地址代码,再按此代码从查询数据库中查出报告的临床意义,建立起一种简便、快捷的处理实验诊断数据的计算机专家系统,为疾病的确诊与治疗提供参考．     

Developmental mechanisms and experimental models to understand forebrain malformative diseases

The development of the central nervous system can be divided into a number of phases, each of which can be subject of genetic or epigenetic alterations that may originate particular developmental disorders. In recent years, much progress has been made in elucidating the molecular and cellular mechanisms by which the vertebrate forebrain develops. Therefore, our understanding of major developmental brain disorders such as cortical malformations and neuronal migration disorders has significantly increased. In this review, we will describe the major stages in forebrain morphogenesis and regionalization, with special emphasis on developmental molecular mechanisms derailing telencephalic development with subsequent damage to cortical function. Because animal models, mainly mouse, have been fundamental for this progress, we will also describe some characteristic mouse models that have been capital to explore these molecular mechanisms of malformative diseases of the human brain. Although most of the genes involved in the regulation of basic developmental processes are conserved among vertebrates, the extrapolation of mouse data to corresponding gene expression and function in humans needs careful individual analysis in each functional system.     

Developmental mechanisms and experimental models to understand forebrain malformative diseases

The development of the central nervous system can be divided into a number of phases, each of which can be subject of genetic or epigenetic alterations that may originate particular developmental disorders. In recent years, much progress has been made in elucidating the molecular and cellular mechanisms by which the vertebrate forebrain develops. Therefore, our understanding of major developmental brain disorders such as cortical malformations and neuronal migration disorders has significantly increased. In this review, we will describe the major stages in forebrain morphogenesis and regionalization, with special emphasis on developmental molecular mechanisms derailing telencephalic development with subsequent damage to cortical function. Because animal models, mainly mouse, have been fundamental for this progress, we will also describe some characteristic mouse models that have been capital to explore these molecular mechanisms of malformative diseases of the human brain. Although most of the genes involved in the regulation of basic developmental processes are conserved among vertebrates, the extrapolation of mouse data to corresponding gene expression and function in humans needs careful individual analysis in each functional system.     

Braindex--an expert system for the diagnosis of brain death

An IBM PC-based system was developed as a decision-supporting system for the diagnosis of brain death. Braindex has been realized with the expert system Tool PC-Plus, and includes a knowledge base containing 300 rules organized in 8 frames. Both forward chaining and backward chaining are used in the inference engine. Braindex also includes a text archive and a lexicon. The data of 42 brain death patients are stored in the data bank (300 parameter per patient). The system is presently in the first stage of clinical application.     

Development of an expert system for the integration of biomarker responses in mussels into an animal health index

Biomarkers on sentinel organisms are utilised worldwide in biomonitoring programs. However, the lack of effective interpretational capacity has hampered their uptake for use for assessment of risk in environmental management. The aim of the present study was to develop and test an objective decision-support or expert system capable of integrating biomarker results into a five-level health-status index. The expert system is based on a set of rules derived from available data on responses to natural and contaminant-induced stress of marine mussels. Integration of parameters includes: level of biological organization; biological significance; mutual inter-relationship; and qualitative trends in a stress gradient. The system was tested on a set of biomarker data obtained from the field and subsequently validated with data from previous studies. The results demonstrate that the expert system can effectively quantify the biological effects of different levels of pollution. The system represents a simple tool for risk assessment of the harmful impact of contaminants by providing a clear indication of the degree of stress syndrome induced by pollutants in mussels.     

Application of rule nets to temporal reasoning in the monitoring of a chemical analysis process

On-line monitoring of the content of ethanol during an alcoholic fermentation process is carried out by means of an expert system based on rule nets. Time has been fully incorporated into the reasoning of the expert system through several timers, which help the rule net to emulate the human reasoning without increasing its complexity. The hierarchy of the variables used is also described in order to understand the whole system.