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The role of causal sequence in the meaning of actions.

Single actions, taken out of context, typically have numerous meanings. Yet, when we observe such actions as part of a sequence of behaviour, we are often unaware of this multiplicity of possible meanings. In this article, we argue that the specific meaning of an action is the result of a process in which people, by making appropriate inferences, relate the actions in a sequence to each other and construct a coherent scenario from them. One implication of this position is that the meaning of actions should be extremely sensitive to the order in which they occur, since order affects which knowledge structures are currently active and is an important clue to the causal and means-end relations among actions. In fact, meaning should be so sensitive to order that it should be possible to construct sets of actions, such that merely by changing the order, the same set of actions could have two radically different meanings. Five sets of such actions were designed. Subjects read one of the two orders for each set of actions and then answered a number of open-ended questions about them. Subjects receiving different orders identified different causes and reasons for the actions, made different predictions about what would happen next, and came to different conclusions about the identities of actors and and objects in the sequences, thus indicating that they had constructed very different meanings for the same actions.

Concept Formation↗

The mood-peak flow relationship in adult asthmatics: a pilot study of individual differences and direction of causality.

The relationship between mood and peak flow (PEF) was examined in 10 adult asthmatics by taking twice daily readings over 15 days. Three subjects showed a clear overall mood-PEF relationship but this effect was attributable to recordings taken in the evening and not those taken in the morning. The size of the mood-PEF relationship correlated significantly with the percentage difference between morning and evening PEF. The results are discussed in terms of the direction of causality between mood and PEF and the need to examine individual differences in the mood-PEF relationship.

Adult↗

Causal beliefs about depression in depressed patients, clinical psychologists and lay persons.

Non-depressed lay persons have been shown to have extensive and accurate knowledge about depression (Rippere, 1977, 1980 a, b, 1981 a) that is underpinned by a structure that resembles current academic theories of the disorder (Furnham & Kuyken, 1991). In this study a semi-structured interview schedule and a number of rating scales were used to determine and compare the nature and extent of depressed patients', clinical psychologists', and lay persons' beliefs about the causes of depression. We confirmed that depressed patients and non-depressed lay persons alike have relatively extensive beliefs about the causes of depression which are comparable to those held by clinical psychologists. However, depressed patients tend to endorse biological explanations of the causes of depression to a greater extent than clinical psychologists. In contrast, clinical psychologists assign a more important causal role to unconscious processes and childhood vulnerability factors than do either depressed patients or non-depressed lay controls.

Adjustment Disorders↗

[Study on septicaemia in infants and children in the past 20 years. Part 1. An analysis of causal organisms].

Causal organisms and their changes were evaluated in 158 cases of septicaemia admitted to Jikei University Hospital from 1975 to 1994. Eighty patients (50.6%) were aged less than 1 year, and 37 patients (23.4%) were newborns. The average mortality rate was 18.4%. The mortality rate between 1975 and 1984 was 26.8%, and that of the past 10 years (from 1985 to 1994) decreased to 13.7%. Staphylococcus aureus (29 cases, 19.4%) was the most common pathogens isolated, followed by Pseudomonas sp. (24 cases, 15.2%), Escherichia coli (19 cases, 12.0%), and Haemophilus influenzae (18 cases, 11.4%). H. influenzae, Acinetobacter sp., Streptococcus pneumoniae and Group B streptococcus (GBS) increased in the past 10 years (from 1985 to 1994), compared with the preceding 10 years (from 1975 to 1984). The mortality rate of Klebsiella sp. septicaemia (28.6%) was highest, followed by Pseudomonas sp. (25.0%), S. aureus (24.1%), S. pneumoniae (22.2%). H. influenzae and Acinetobacter sp. septicaemia were not fatal. E. coli and GBS were common among neonates and patients aged less than 1 year. H. influenzae septicaemia occurred mainly in patients with meningitis, in those younger than school age. Acinetobacter sp. was common among neonates and children with leukaemia Pseudomonas sp., Klebsiella sp., and Acinetobacter sp. were mainly detected in patients with underlying diseases. E. coli, H. influenzae, S. pneumoniae and GBS were mainly detected in patients without underlying diseases.

Adolescent↗

Finite-bandwidth effects on the causal prediction of ultrasonic attenuation of the power-law form.

Kramers-Kronig (K-K) relations exist as a consequence of causality, placing nonlocal constraints on the relationship between dispersion and absorption. The finite-bandwidth method of applying these relations is examined where the K-K integrals are restricted to the spectrum of the experimental data. These finite-bandwidth K-K relations are known to work with resonant-type data and here are applied to dispersion data consistent with a power-law attenuation coefficient (exponent from 1 to 2). Bandwidth-restricted forms of the zero and once-subtracted K-K relations are used to determine the attenuation coefficient from phase velocity. Analytically, it is shown that these transforms produce the proper power-law form of the attenuation coefficient as a stand-alone term summed with artifacts that are dependent on the integration limits. Calculations are performed to demonstrate how these finite-bandwidth artifacts affect the K-K predictions under a variety of conditions. The predictions are studied in a local context as a function of subtraction frequency, bandwidth, and power-law exponent. The K-K predictions of the power-law exponent within various decades of the spectrum are also examined. In general, the agreement between finite-bandwidth K-K predictions and exact values grows as the power-law exponent approaches 1 and with increasing bandwidth.

Models, Theoretical↗

Implications of causality, time-translation invariance, linearity, and minimum-phase behavior for basilar membrane response functions.

Several implications of the assumptions of causality (C), time-translation invariance (TTI), linearity (L), and minimum phase behavior (MPB) for basilar membrane (BM) frequency-response functions are derived. They are then used to: (1) test the consistency of calculated results for a two-dimensional cochlear model [S. T. Neely, J. Acoust. Soc. Am 69, 1386-1393 (1981)] and (2) check experimental data on the BM displacement/malleus displacement [W, S. Rhode, J. Acoust. Soc. Am. 67, 1969-1703 (1980)] for approximate consistency with these assumptions. Both the theoretical model results and experimental cochlear-partition response data are in fairly good accord with these assumptions.

Acoustics↗

Causality, consciousness, and cerebral organization.

This article is based upon data which are suitable for the correlation of behavioral research and experimental neurophysiology. Causal thinking manifests a sort of integrative activity which brings simultaneous and successive patterns of nervous excitation into a subjectively meaningful frame of reference. While neuronal patterns determine the content of consciousness, they fail to provide clues concerning the transformation of such patterns into subjective experience.

Animals↗

Efficacy of azithromycin as a causal prophylactic agent against murine malaria.

The efficacy of the newly marketed azalide azithromycin was compared with that of the clinical agent doxycycline in a murine model of sporozoite-induced malaria. Drug was administered once; Plasmodium yoelii sporozoites were administered 2 h later; survival at day 60 was determined. For parenterally administered drug, 160 mg of azithromycin or doxycycline per kg of body weight was 100% effective; 40 mg of azithromycin per kg was 80% effective, but 40 mg of doxycycline per kg was 40% effective. Orally administered azithromycin was somewhat less effective than parenterally administered drug, consistent with the 37% clinical oral bioavailability of this agent. For orally administered azithromycin, 160 mg/kg was 100% effective and 40 mg/kg was 40% effective. The efficacy of azithromycin in comparison with that of doxycycline and the known prolonged levels of azithromycin in the livers of humans suggest that azithromycin has potential as a clinical causal prophylactic agent for malaria.

Animals↗

Genetically determined susceptibility to tuberculosis in mice causally involves accelerated and enhanced recruitment of granulocytes.

Classical twin studies and recent linkage analyses of African populations have revealed a potential involvement of host genetic factors in susceptibility or resistance to Mycobacterium tuberculosis infection. In order to identify the candidate genes involved and test their causal implication, we capitalized on the mouse model of tuberculosis, since inbred mouse strains also differ substantially in their susceptibility to infection. Two susceptible and two resistant mouse strains were aerogenically infected with 1,000 CFU of M. tuberculosis, and the regulation of gene expression was examined by Affymetrix GeneChip U74A array with total lung RNA 2 and 4 weeks postinfection. Four weeks after infection, 96 genes, many of which are involved in inflammatory cell recruitment and activation, were regulated in common. One hundred seven genes were differentially regulated in susceptible mouse strains, whereas 43 genes were differentially expressed only in resistant mice. Data mining revealed a bias towards the expression of genes involved in granulocyte pathophysiology in susceptible mice, such as an upregulation of those for the neutrophil chemoattractant LIX (CXCL5), interleukin 17 receptor, phosphoinositide kinase 3 delta, or gamma interferon-inducible protein 10. Following M. tuberculosis challenge in both airways or peritoneum, granulocytes were recruited significantly faster and at higher numbers in susceptible than in resistant mice. When granulocytes were efficiently depleted by either of two regimens at the onset of infection, only susceptible mice survived aerosol challenge with M. tuberculosis significantly longer than control mice. We conclude that initially enhanced recruitment of granulocytes contributes to susceptibility to tuberculosis.

Animals↗

Verification of causal relationships between Listeria monocytogenes isolates implicated in food-borne outbreaks of listeriosis by randomly amplified polymorphic DNA patterns.

Food and clinical isolates of Listeria monocytogenes recovered from four different outbreaks of listeriosis were analyzed by their PCR-based randomly amplified polymorphic DNA (RAPD) patterns to verify their causal relationships. The generation of DNA fingerprints by PCR-based RAPD analysis is a fast and sensitive method for the epidemiological tracking and identification of bacteria implicated in food poisoning outbreaks. The L. monocytogenes strains used in the study were obtained from the following four outbreaks: California, 1985, Mexican-style cheese; Canadian Maritime Provinces, 1981, coleslaw; Canada, 1989, brie cheese; and Canada, 1989, alfalfa tablets. RAPD profiles were generated by using random 10-mer primers for at least one food and one clinical isolate recovered from each outbreak. Identical profiles for 20 different primers were observed for each pair of food and clinical isolates from two of the four outbreaks. Isolates from the outbreak involving alfalfa tablets exhibited identical patterns for 19 primers; however, primer OPA-1 produced one additional 1.8-kb fragment, designated OPA-1-1.8, that was found in the food isolate but not in the corresponding clinical isolate. Hybridization analysis revealed that the absence of the OPA-1-1.8 polymorphic fragment in the clinical isolate was due to a deletion of at least 1.8 kb. Loss of the OPA-1-1.8 polymorphic fragment could not be induced by infective passage of the L. monocytogenes isolate from the alfalfa tablet through a mouse or by growth of this isolate under selective conditions. This suggests that the isolate recovered from the food was not identical to the isolate recovered from the patient. The ability to produce unique RAPD patterns allows for the discrimination between isolates even if they are of the same serotype and multilocus enzyme electrophoretic type.

Animals↗

Chlamydia pneumoniae in atheroma: consideration of criteria for causality.

AIMS: (1) To seek evidence of the existence of Chlamydia pneumoniae in a spectrum of atheromatous lesions in different types of arteries from individuals of different ages, using a polymerase chain reaction (PCR) assay supported by electron microscopy and immunocytochemistry; (2) to use electron microscopy to examine interactions between C pneumoniae and the cells present in the arterial tissue; (3) to assess the extent to which the data fulfil the criteria for causality. METHODS: At necropsy examination, 35 arterial specimens were taken from 25 subjects. The grade of atheroma was determined macroscopically and microscopically and the tissues coded and examined by the three techniques. RESULTS: Of the 35 specimens, 24 had macroscopic or microscopic atheromatous lesions of varying degree. Twenty two of the 35 specimens were examined by electron microscopy, C pneumoniae-like bodies being found in 11 (50%); seven specimens were examined by the immunocytochemical method, positive staining being detected in three; and all specimens were examined by the PCR technique, 15 (43%) being PCR positive. Overall, of the 24 specimens with lesions, 17 (71%) were positive by at least one of the three tests, whereas of the 11 specimens without lesions, only one was positive. The positive specimens comprised 10 of 19 aortas, three of six iliac arteries, and one coronary and one pulmonary artery. C pneumoniae was detected in four of six specimens in which there were early changes and in a 20 year old subject. Concerning the 25 subjects, of 17 who had atheromatous arteries, 14 (82%) were C pneumoniae positive and of the eight who had normal arteries, none was positive. CONCLUSIONS: There is a strong correlation between C pneumoniae and arterial atheromatous lesions. The organism may contribute to the disease process by damaging smooth muscle cells.

Adult↗

Income inequality and physical and mental health: testing associations consistent with proposed causal pathways.

OBJECTIVES: To test associations between individual health outcomes and ecological variables proposed in causal models of relations between income inequality and health. DESIGN: Regression analysis of a large, nationally representative dataset, linked to US census and other county and state level sources of data on ecological covariates. The regressions control for individual economic and demographic covariates as well as relevant potential ecological confounders. SETTING: The US population in the year 2000. PARTICIPANTS: 4817 US adults about age 40, representative of the US population. MAIN OUTCOME MEASURES: Two outcomes were studied: self reported general health status, dichotomised as "fair" or "poor" compared with "excellent", "very good", or "good", and depression as measured by a score on the Center for Epidemiologic Studies depression instrument >16. RESULTS: State generosity was significantly associated with a reduced odds of reporting poor general health (OR 0.84, 95%CI: 0.71 to 0.99), and the county unemployment rate with reduced odds of reporting depression (OR 0.91, 95%CI: 0.84 to 0.97). The measure of income inequality is a significant risk factor for reporting poor general health (OR 1.98, CI: 1.08 to 3.62), controlling for all ecological and individual covariates. In stratified models, the index of social capital is associated with reduced odds of reporting poor general health among black people and Hispanics (OR 0.40, CI: 0.18 to 0.90), but not significant among white people. The inequality measure is significantly associated with reporting poor general health among white people (OR 2.60, CI: 1.22 to 5.56) but not black people and Hispanics. CONCLUSIONS: The effect of income inequality on health may work through the influence of invidious social comparisons (particularly among white subjects) and (among black subjects and Latinos) through a reduction in social capital. Researchers may find it fruitful to recognise the cultural specificity of any such effects.

Adult↗

Shift work and subfecundity: a causal link or an artefact?

AIMS: The Danish National Birth Cohort (DNBC) was used to examine whether shift work is associated with reduced fecundity as estimated by time to pregnancy (TTP). METHODS: From 1 March 1998 to 1 May 2000, 39 913 pregnant women were enrolled in the DNBC. Data on job characteristics and TTP (0-2, 3-5, 6-12, and >12 months) were used for 17 531 daytime workers and 3907 shift workers who had planned the pregnancy. Fecundity odds ratios (ORs) were calculated with 95% confidence intervals using the discrete time survival analysis techniques performed by logistic regression. An OR above 1 expresses a shorter TTP and then a higher fecundity. Potential confounders, such as age at conception, gravidity, prepregnant body mass index, smoking, and alcohol consumption, as well as occupational characteristics, were also included in the model. RESULTS: Fixed evening workers and fixed night workers had a longer TTP. Compared with daytime workers, the adjusted ORs were 0.80 (95% CI 0.70 to 0.92) for fixed evening workers, 0.80 (95% CI 0.63 to 1.00) for fixed night workers, 0.99 (95% CI 0.91 to 1.07) for rotating shift (without night) workers, and 1.05 (95% CI 0.97 to 1.14) for rotating shift (with night) workers. When analysis was restricted to nulliparous women, the estimates remained unchanged. The proportions of unplanned pregnancies and contraceptive failures were higher among fixed evening and fixed night workers. CONCLUSIONS: There was no unequivocal evidence of a causal association between shift work and subfecundity. The slightly reduced fecundity among fixed evening workers and fixed night workers may be mediated by pregnancy planning bias or differential options for sexual contacts.

Circadian Rhythm↗

Vulvodynia and HIV: causal or casual association?

BACKGROUND: No study exists on HIV and vulvodynia. OBJECTIVE: To evaluate vulvodynia in HIV infected women and its possible association with HIV. DESIGN: Cross sectional study. SETTING: Department of Medical and Surgical Sciences, Section of Infectious Diseases, University of Turin. METHODS: 235 HIV positive and 272 HIV negative women were studied for vulvar pain between June 1995 and January 1997. Diagnosis of vulvodynia was based on clinical history, dermatological and vulvovaginal examination, and bacteriology. Colposcopy and vulvar biopsy were performed and psychometric examination was done. RESULTS: Vulvodynia was diagnosed in five women with HIV and in one uninfected woman (odds ratio = 2.5; 95% confidence interval: 0.1-62.6). High neuroticism scores were observed in women with history of vulvar pain, the highest in HIV infected vulvodynia patients (p = 0.000). CONCLUSIONS: Confirming the association of gynaecological pain with neurotic personality, our study suggests causal link between HIV and vulvodynia.

Adult↗

Papillomas of the teats and udder of cattle and their causal viruses.

An abattoir survey was carried out on 1657 cattle to determine the incidence and parameters of teat and udder papillomas and their causal viruses. Recent research has characterised six different bovine papillomaviruses of which three have been found to be particularly associated with teat tumours. Of the population studied 37.3 per cent had teat warts and 86.2 per cent of these had multiple infections; 28.4 per cent had papillomas attributed to bovine papillomavirus 1, 88.5 per cent to bovine papillomavirus 5 and 92.3 per cent to bovine papillomavirus 6. There was no predilection site between teats. Herefords and their crosses dominated the breed incidence and showed the highest numbers of warts but it was not possible to make a realistic comparison with other breeds. Dairy cattle were poorly represented. Bovine papillomavirus 4 was never found and from this it was concluded that there is no association between alimentary and teat papillomas. The implications of these findings in terms of prophylaxis and control are discussed.

Animals↗

Inhibition of Fusarium moniliforme var. subglutinans, the causal agent of pine pitch canker, by the soil bacterium Arthrobacter sp.

A species of Arthrobacter was recovered during culture of the causal organism of pitch canker of southern pines. Fusarium moniliforme var. subglutinans (FMS). Arthrobacter is a relatively common soil bacterium and is lytic to several fungal pathogens in the soil. Soil samples from two seed orchards with pitch canker and one from a healthy pine plantation all yielded Arthrobacter. These isolates were evaluated for their ability to inhibit the growth of FMS isolates from pitch canker tissue and from soil in areas with high pitch canker disease incidence, and to several other species of Fusarium isolated from the same soil samples where Arthrobacter was recovered. Generally the pitch canker isolates were more sensitive to Arthrobacter than the soil fusaria. There was variation in the ability of the Arthrobacter isolates to inhibit the growth of the fusaria recovered from the soil at the three different test sites. Light and scanning electron microscope observations revealed that hyphae of FMS growing near an isolate of Arthrobacter were enlarged, producing many vesicularlike structures. The surface of these hyphae was warped and wrinkled in comparison with normal hyphae.

Antibiosis↗

Comparing personal trajectories and drawing causal inferences from longitudinal data.

This review considers statistical analysis of data from studies that obtain repeated measures on each of many participants. Such studies aim to describe the average change in populations and to illuminate individual differences in trajectories of change. A person-specific model for the trajectory of each participant is viewed as the foundation of any analysis having these aims. A second, between-person model describes how persons very in their trajectories. This two-stage modeling framework is common to a variety of popular analytic approaches variously labeled hierarchical models, multilevel models, latent growth models, and random coefficient models. Selected published examples reveal how the approach can be flexibly adapted to represent development in domains as diverse as vocabulary growth in early childhood, academic learning, and antisocial propensity during adolescence. The review then considers the problem of drawing causal inferences from repeated measures data.

Adolescent↗

Is microvascular protection by cariporide and ischemic preconditioning causally linked to myocardial salvage?

Two independent cardioprotective interventions, Na(+)/H(+) exchange inhibition and ischemic preconditioning (PC), were investigated with respect to differential effects on microvascular and myocardial salvage in anesthetized rabbits (30 min of ischemia, 180 min of reperfusion). Cariporide (Car, 300 microg/kg) administered before occlusion and PC reduced infarct size (IS) as measured by triphenyltetrazolium staining [control, 46.0 +/- 4.2% of risk area (RA); Car, 17.6 +/- 3.7% (P < 0.01); PC, 27.5 +/- 4.1% (P < 0.01)] and concomitantly decreased the area of anatomic no reflow (ANR) as measured by thioflavin S staining [control, 40.4 +/- 3.7%; Car, 19.0 +/- 2.9% (P < 0.01); PC, 26.9 +/- 3.4% (P < 0.05)]. Regional myocardial blood flow (RMBF, measured by radioactive microspheres) in the RA, which deteriorated between 30 and 180 min of reperfusion (control, from 79 +/- 6 to 26 +/- 2% of nonischemic flow), was shifted to higher values with both treatments [Car, from 110 +/- 12 to 49 +/- 7% (P < 0.05); PC, from 109 +/- 8 to 38 +/- 6% (P < 0.05)]. However, neither intervention uncoupled the close relationship between IS and ANR (r = 0.92-0.95) or RMBF. Car given at reperfusion did not alter IS, ANR, RMBF, or the close interrelationships. Because size and spatial distribution of no reflow and myocardial necrosis remained closely coupled with independent cardioprotective interventions, a potential causal connection between microvascular and myocardial salvage is discussed.

Animals↗