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Two studies were conducted to explore the relationships between perceived job performance, causal attributions, employee affect, and expectations for a day's work. In both studies, causal categories derived from previous attribution research were found to correspond with employee job explanations. However, results somewhat inconsistent with previous laboratory studies were obtained.
Conceptual dichotomies between mind and brain, psychology and neuroscience, meaning and causation, and fact and value confound thinking in philosophy of mind, clinical psychiatry, and psychiatric ethics. Paul Churchland's theory of eliminative materialism highlights these dichotomies, stating that advances in neuroscience have restricted, and eventually will eliminate, any need for psychology. The core principles of this theory are questionable, because psychiatrists still need psychology and perhaps always will. The main argument in this essay is that even in cases of well-defined brain pathology (where eliminative materialism seems most plausible), psychological concepts remain critical. Thus, philosophers and psychiatrists should generate conceptual models that lead not to eliminativism but to explanatory pluralism, which is the pragmatic integration of diverse concepts toward the end of better handling clinical challenges. The contributions of Karl Jaspers in opposition to eliminative materialism and in support of pluralism are discussed. Jaspers delineated the role of meaningful psychological explanation in a psychiatry rooted in neuroscientific explanation. However, his notion that meaningful states do not have causal power is disputable and has come under fire in recent philosophy of mind and cognitive neuroscience, which highlight the possibility that meaningful psychological states can be causally significant. This idea has implications for psychiatric ethics and the fact/value debate.
Previous studies have shown that a negative relationship exists between transpiration efficiency (TE) and carbon isotope discrimination (Delta) and between TE and specific leaf area (SLA) in Stylosanthes scabra. A glasshouse experiment was conducted to confirm these relationships in an F(2) population and to study the causal nature of these relationships through quantitative trait loci (QTL) analysis. One hundred and twenty F(2) genotypes from a cross between two genotypes within S. scabra were used. Three replications for each genotype were maintained through vegetative propagation. Water stress was imposed by maintaining plants at 40% of field capacity for about 45 d. To facilitate QTL analysis, a genetic linkage map consisting of 151 RAPD markers was developed. Results from this study show that Delta was significantly and negatively correlated with TE and biomass production. Similarly, SLA showed significant negative correlation with TE and biomass production. Most of the QTL for TE and Delta were present on linkage groups 5 and 11. Similarly, QTL for SLA, transpiration and biomass productivity traits were clustered on linkage groups 13 and 24. One unlinked marker was also associated with these traits. There were several markers coincident between different traits. At all the coincident QTL, the direction of QTL effects was consistent with phenotypic data. At the coincident markers between TE and Delta, high alleles of TE were associated with low alleles of Delta. Similarly, low alleles of SLA were associated with high alleles of biomass productivity traits and transpiration. At the coincident markers between trans-4-hydroxy-N:-methyl proline (MHP) and relative water content (RWC), low alleles of MHP were associated with high alleles of RWC. This study suggests the causal nature of the relationship between TE and Delta. Phenotypic data and QTL data show that SLA was more closely associated with biomass production than with TE. This study also shows that a cause-effect relationship may exist between SLA and biomass production.
We often have cases of insecticide poisoning where the patient is unconscious and the causal substances are unknown. We report an 83-year-old unconscious man who had apparently ingested several agricultural chemicals, possibly organophosphate or carbamate. According to his family, there were three kinds of containers of agricultural chemicals with their caps opened around him. When he was transferred to our hospital, he presented hypertension, hypersalivation, and muscle fasciculation. His pupils were markedly miotic. In order to identify the substances ingested we used a gas chromatographymass spectrometer (GCMS) using his gastric content. Within 30 minutes we were able to identify the causal substance as methomyl, one of the popular carbamates, thereby eliminating the need to use pralidoxime (PAM). GCMS makes it possible to identify unknown substances quickly and accurately and is therefore extremely useful in deciding the appropriate treatment.
Although it is well-established that vulnerability to negative emotion is associated with attentional bias toward aversive information, the causal basis of this association remains undetermined. Two studies addressed this issue by experimentally inducing differential attentional responses to emotional stimuli using a modified dot probe task, and then examining the impact of such attentional manipulation on subsequent emotional vulnerability. The results supported the hypothesis that the induction of attentional bias should serve to modify emotional vulnerability, as revealed by participants' emotional reactions to a final standardized stress task. These findings provide a sound empirical basis for the previously speculative proposal that attentional bias can causally mediate emotional vulnerability, and they suggest the possibility that cognitive-experimental procedures designed to modify selective information processing may have potential therapeutic value.
Two experiments, incorporating both real-life (Experiment 1) and artificial (Experiment 2) stimuli, demonstrated that lay concepts of mental disorders can be reliably predicted from subjects' naive causal theories about those disorders. Symptoms that are deeper causes (X, where X causes Y, which causes Z) are more important in lay concepts than intermediate causes (Y), which in turn are more important than terminal effects (Z). In addition, symptoms that cause or are caused by other symptoms are more important in lay concepts than symptoms not participating in any causal relationships. Implications of these results for current models of categorization and for research on lay theories of mental disorders are discussed, and future directions for research are suggested.
Associative and statistical theories of causal and predictive learning make opposite predictions for situations in which the most recent information contradicts the information provided by older trials (e.g., acquisition followed by extinction). Associative theories predict that people will rely on the most recent information to best adapt their behavior to the changing environment. Statistical theories predict that people will integrate what they have learned in the two phases. The results of this study showed one or the other effect as a function of response mode (trial by trial vs. global), type of question (contiguity, causality, or predictiveness), and postacquisition instructions. That is, participants are able to give either an integrative judgment, or a judgment that relies on recent information as a function of test demands. The authors concluded that any model must allow for flexible use of information once it has been acquired.
A shift from a traditional biogeographical paradigm in cladistic biogeography to a chronobiogeographical paradigm is proposed. The chronobiogeographical paradigm aims to utilize temporal data in conjunction with spatial data in the detection of discrete historical events, such as vicariance and vicariant speciation, in cladograms. The concepts of primary and secondary congruency are introduced in relation to the distinction between repeated area relationships (primary congruency) and common extrinsic causality (secondary congruency). Simple hypothetical examples demonstrate that area cladograms cannot be safely interpreted purely as representing the sequence of area fragmentation; rather, they reflect recency of biotic interaction. Temporal data are shown to have a direct and potentially profound influence on the results of traditional cladistic biogeographical analyses, indicating the necessity of developing a chronobiogeographical approach. The implementation of the paradigm is considered first from a theoretical viewpoint and then in the context of the type of empirical data usually available. An as yet undevised "time/space algorithm" is deemed necessary for the latter, and guidelines are presented for the development of such an algorithm. Finally, we argue that the most rigorous and philosophically justified approach to the detection of phylogenetic causal events can be found only when temporal and spatial data are considered simultaneously. Consequently, the chronobiogeographical paradigm is seen as a logical elaboration of, not a replacement for, the biogeographical paradigm.
We describe our work on HEPAR II, a probabilistic causal model for diagnosis of liver disorders. The model, a Bayesian network capturing the causal interactions among various risk factors, diseases, symptoms, and test results, is based on expert knowledge combined with clinical data captured in medical records. The main applications of HEPAR II are assistance is diagnosis and training of beginning diagnosticians. We outline the principles of the applied approach, present a brief description of the model, and report its diagnostic performance.
Biological data can be scarce and costly to obtain. The small number of samples available typically limits statistical power and makes reliable inference of causal relations extremely difficult. However, we argue that statistical power can be increased substantially by incorporating prior knowledge and data from diverse sources. We present a Bayesian framework that combines information from different sources and we show empirically that this lets one make correct causal inferences with small sample sizes that otherwise would be impossible.
Early odor preference learning in rats is associated with increases of phosphorylated CREB (pCREB) in mitral cells of the olfactory bulb. In the present study, herpes simplex virus expressing CREB (HSV-CREB) and dominant-negative mutant CREB (HSV-mCREB) have been injected into the bulb to assess a causal role for CREB and pCREB in this model. Odor paired with stroking or with the beta-adrenoceptor agonist isoproterenol produces odor approach 24 hr later. Isoproterenol-induced learning exhibits an inverted U curve dose-dependent learning relationship with both low and high doses failing to produce learning. pCREB increases have only been seen at the learning effective dose. In the present study, injection of an HSV vector expressing mutant CREB into the olfactory bulb prevented learning induced by stroking. Control HSV expressing LacZ was without effect. Expression of mutant CREB shifted the dose-learning curve for isoproterenol to the right such that a higher dose was required to induce learning. Expression of CREB shifted the dose-learning curve for isoproterenol to the left, with a lower dose now producing learning. As expected from this shift, CREB overexpression interfered with learning induced by stroking. When learning occurred, with either CREB or mutant CREB, pCREB was observed to be elevated relative to the nonlearning LacZ control groups. Unexpectedly, with odor plus stroking in the nonlearning CREB group, the level of pCREB was also higher than with odor plus stroking in LacZ controls that did learn. The data demonstrate a causal role for CREB and pCREB in early mammalian odor preference learning, reinforcing CREB as a "universal" memory molecule. They support evidence that CREB overexpression can be deleterious and suggest the hypothesis of an optimal pCREB window for learning.
Reported are the results of a case study from Kirotshe rural health district, Northern Kivu, Zaire, where a workshop on the causal model approach to nutrition was organized in 1987. The model has since been used in the field for research design, training of health professionals, nutrition intervention, and community development. The rationale behind this approach is reviewed, the experience accumulated from Kirotshe district is described, and the ways in which the causal model contributes to comprehensive health and nutrition care are discussed. The broad range of possible policy implications of this approach underlines its usefulness for future action.
IARC evaluations of the carcinogenic risk to humans, although based on epidemiological and experimental studies, derive their value from the consensus among committee members on a decision based on the current status of knowledge, not from the studies themselves, nor from their summary evaluation. A judiciary setting, based on the opinion of an individual expert, or on the evaluation of the most updated state of the knowledge by a group of experts selected in non scientific settings, or even worse on the evaluation of a specific case with ad hoc epidemiological studies, cannot confute such decisions. Therefore, causal links already defined within the scientific community, such as between exposures in the IARC category 1 and specific cancer sites, should be accepted also in legal trials to establish individual responsibility in case of excess exposures for the general and/or the working population resulting from violation or omission of preventive duties, when those diseases follow such excess exposures. If no violation or omission occurred, a civil responsibility has to be defined when either a disease with established link with the given exposure occurs, or a disease for which no such a level of consensus exists in the scientific community, but for which the legal trial has reached a positive decision. In such instances, if omissions or law violations occurred, the legal trial carries the burden of establishing a causal link between such omissions and violations and the damage for the individual worker or citizen.
Databases have collected masses of information concerning cell signaling pathways that includes information on pathways, molecular interactions as well as molecular complexes. However we have no general data model to represent comprehensive properties of cell signaling pathways, so that this type of information has been represented by two different data models that we call 'binary relation' and 'state transition'. The disagreement between the existing models derives from lack of consensus about a factor of causality in reactions in cell signaling pathways, which is often called 'signal'. We developed an ontology named CSNO (Cell Signaling Networks Ontology) based on device ontology. As device ontology is a research product of knowledge engineering, CSNO is the first application of it to biological knowledge. CSNO defines the factor of causality called 'signal', offers an integrative viewpoint for the two different data models, explicates intrinsic distinctions between signaling and metabolic pathways, and eliminates ambiguity from representation of complex molecules.
Type 1 diabetes mellitus (T1DM) results from environmental factors acting on genetically susceptible individuals. Microbial infections and their immunological consequences are suspected to take part in the pathogenesis of T1DM. Congenital rubella infection has been strongly associated with increased disease susceptibility. In addition, infections with different strains of enteroviruses, human cytomegalovirus, and rotavirus have been suggested to be diabetogenic in susceptible individuals. A newly emerged hypothesis states that a bacterial toxin, bafilomycin A1 produced by Streptomyces spp, could be the cause of pancreatic beta-cell damage. In some instances, microbial infections may even protect the individual from T1DM. There are several proposed mechanisms of beta-cell damage caused by microbes. T1DM can result from direct cytolysis of beta-cells. Other suggested mechanisms are cross-reactivity between microbial proteins and self antigens (molecular mimicry), bystander activation of lymphocytes, and alterations in cytokine concentrations affecting T-helper cell balance in the vicinity of pancreatic beta-cells. Proving a causal role between microbial infections and T1DM appears difficult. Despite intensive research, a final conclusion concerning the causal role of microbes in the pathogenesis of T1DM has not been made.
The purposes of this research were 1) to study the effectiveness of Internal Quality Assurance (IQA) of the Health science area, and 2) to study the factors affecting the effectiveness of the IQA of the Health science area. A causal model has been developed by the researcher comprised of the 6 exogenous latent variables: Attitude towards quality assurance, Teamwork, Staff training, Resource sufficiency, Organizational culture, and Leadership, and the 4 endogenous latent variables, which are the effectiveness of the IQA, Student-centered approach, Decentralized administration, PDCA cycle of work (Plan-Do-Check-Act), and Staff job satisfaction. The research sample consisted of 108 health science faculties derived by stratified random sampling technique. Data were collected by 10 questionnaires having reliability ranging from 0.79 to 0.96. Data analyses were descriptive statistics, and Linear Structure Relationship (LISREL) analysis. The major findings were as follows: 1. The 4 dimensions of effectiveness for the IQA of the Health science areas were significantly higher at the .05 level, after the Health science faculty applied the IQA programme according to the National Education Act of 1999. 2. The causal model of the effectiveness of the IQA was valid and fitted the empirical data. The 6 predictors accounted for 83% of the variance in the effectiveness of IQA. Culture and Leadership were the predictors that significantly accounted for the effectiveness of the IQA.
Iran is considered a major genetic for medicinal plant in the world. Because of this significant diversity and historical background in identification and utilization to remedy human and animal diseases, export of medicinal plant can help to strengthen local as well as natural economy. Buglosse (Fig. 1) is one of the most important and common medicinal plants in Iran and exist as Echium amoneum and Borago officinalis. This work was conducted in order to identify the causal agent(s) of damping off disease in buglosse. Plant disease samples were taken from Esfahan and Tehran provinces. Symptoms on original plant including root, crown rot, dark tissue, pith and hallow root were collected in order to isolate disease agent(s). Symptomatic root and crown tissues after surface sterilization with 96% ethanol were transferred on to PDA and WA media and also on moist filter paper in petri dishes. Two fungal colonies grew from tissue segments and spore culture was subsequently purified. The fungal isolate identified as Rhizoctonia solani based on the following test. Hyphal tip was removed from colony margin placed on PDA and PSA media and incubated in dark. Colony diameter of one hundred hyphae measured and nucleus was stained according to Bandoni (1979), Kronland and Stanghellini (1988). It was observed that in each cell of hyphae there are more than two nuclei. Single spore culture were obtained from macroconidia of Fusarium isolate. After 24 hr of incubation, growing single spore were transferred to KCL medium to detect spore chains. Fungal isolates transferred to PSA and PDA media for sporulation. After 7 days colonies appeared as white cream to pinkish on top and cream to dark pink at the bottom of petri dish with abundant micro and macro conidia. Colonies were snow white, felting shape, with ample causal hyphae on PSA medium. On KCL medium, fungal growth was superficial and colonies were colorless with long macroconidia and individual sausage-shape macroconidia being thinner one side and having maximum four septa. Microconidia were long double compartment round on both side, straight to slightly curved. Base on morphology and dimension of conidia and production of chlamidospore the funguses identify as Fusarium solani.
Full rehabilitation of a patient following myocardial infarction (MI) involves resumption of work and the restoration of quality of life. Two groups of patients (87 Israeli and 98 Swedish) were admitted to the CCU and followed up after their first MI. To evaluate the patients' own perception of events ('causal attribution theory'), sequential interviews were scheduled. Physical risk factors correlated poorly with rehabilitation outcome at 6 months. However, two patient clusters were pinpointed according to the patients' subjective explanation of the factors contributing to their MI. These 'causal attribution scores' had a predictive value, independent of culture, age, education, disease severity and depression. It is therefore concluded that evaluation of patient perception may assist in planning intervention for high risk psychologically debilitated patients, and thus favourably enhance their rehabilitation outcome.