Different Pattern Of Effects Research Articles

The association of community violence exposure with middle-school achievement: A prospective study

This study investigated the long-term effects of exposure to community violence on academic achievement and feelings of safety in school among a large sample of urban middle-school students ( N = 759). It also considered the role of depressive symptoms and aggression as mediators of the effects, and the role of parent support in buffering adolescents from these effects of violence exposure. Different patterns of effects were found for exposure to violence as witnesses or as victims. Witnessing was associated with lower levels of academic achievement over time, and these longitudinal effects were not mediated by depressive symptoms or aggression, nor were they buffered by parent support. Victimization was not related to lower levels of academic achievement and was associated with feeling less safe in school over time only for boys who reported low levels of parent support. Intervention and policy implications highlight the importance of an ecological approach in intervening to boost the academic performance of urban children placed at risk.

MOST SMOKELESS TOBACCO USE IS NOT A CAUSAL GATEWAY TO CIGARETTES: RESPONSE TO TOMAR & LOREE 2004

MOST SMOKELESS TOBACCO USE IS NOT A CAUSAL GATEWAY TO CIGARETTES: RESPONSE TO TOMAR & LOREE 2004

日本版ＭＢＩ‐ＧＳ（Ｍａｓｌａｃｈ Ｂｕｒｎｏｕｔ Ｉｎｖｅｎｔｏｒｙ‐Ｇｅｎｅｒａｌ Ｓｕｒｖｅｙ）の妥当性の検討

The purpose of this study was to validate Japanese research version of Maslach Burnout Inventory-General Survey (MBI-GS), a newly developed measure intended for persons of every occupation. The Japanese MBI-GS was administered to a sample of hospital workers. Exploratory factor analysis found three factors, as in original MBI-GS. Confirmatory factor analysis largely supported MBI-GS structure of three subscales, but the correlation between two subscales was unexpectedly high. To examine its construct validity, the subscale scores were then examined in relation to selected work characteristics. Conservation of resources theory was successful in its predictions of different patterns of effects among the correlates and three burnout subscales. The successful predictions suggested that meaning of each subscale was quite distinct. In all, our examination showed that Japanese MBI-GS assessed the same three dimensions as the original measure for human service workers.

Early processing of the six basic facial emotional expressions

Facial emotions represent an important part of non-verbal communication used in everyday life. Recent studies on emotional processing have implicated differing brain regions for different emotions, but little has been determined on the timing of this processing. Here we presented a large number of unfamiliar faces expressing the six basic emotions, plus neutral faces, to 26 young adults while recording event-related potentials (ERPs). Subjects were naive with respect to the specific questions investigated; it was an implicit emotional task. ERPs showed global effects of emotion from 90 ms (P1), while latency and amplitude differences among emotional expressions were seen from 140 ms (N170 component). Positive emotions evoked N170 significantly earlier than negative emotions and the amplitude of N170 evoked by fearful faces was larger than neutral or surprised faces. At longer latencies (330–420 ms) at fronto-central sites, we also found a different pattern of effects among emotions. Localization analyses confirmed the superior and middle-temporal regions for early processing of facial expressions; the negative emotions elicited later, distinctive activations. The data support a model of automatic, rapid processing of emotional expressions.

Anticoverage Models for Obnoxious Material Transportation

We present models for the design of routes for transportation of loads that might become hazardous or obnoxious to the population living along these routes. We take into consideration the fact that the values of the properties that are close to the roads used for the transportation may decrease as a consequence of this activity. As opposed to the traditional approach, of minimizing the population along the routes, we propose to include a compensation cost as a direct cost of choosing the routes. This compensation could include, for instance, a reduction in property tax rates. Two formulations are presented, covering different patterns of effects on property values. As an example of application of the models, we provide some computational experience.

Examining the Effects of Parental Absence on the Academic Achievement of Adolescents: The Challenge of Controlling for Family Income

Increasingly, researchers are concerned about how to best control for family income when examining the effects of parental divorce and the death of a parent on the children's academic achievement. Some researchers have argued that a predissolution control is preferable over a postdissolution control for family income, because parental divorce or the death of a parent nearly always causes family income reduction. Using the National Educational Longitudinal Study 1988–92 data set, this study has examined whether using a predissolution control for family income yields a different pattern of effects from when a postdissolution control is used. The results indicate that using a predissolution control rather than a postdissolution control for family income does yield a different pattern of effects.

Environmental temperature during pregnancy and eating attitudes during teenage years: a replication and extension study.

Among nonclinical adolescents, restrictive eating attitudes are more likely to occur among females born during warmer months. The present study aimed to replicate this finding and to extend it, considering whether such an effect is found in males and across the teenage years. In addition, the influence of temperature across the intrauterine period was considered. The participants consisted of younger and older teenagers, all born in England. Each completed the relevant scales of the Eating Disorders Inventory and provided demographic information. Temperature across fetal development was determined using national meteorological records. There was a positive link between restrictive attitudes and temperature at birth among the older female group, although this replication effect did not reach significance. The same association among the older males was highly significant. The range of temperatures during fetal development also predicted later restrictive attitudes. In contrast, these effects were not replicated among the younger group, where a different pattern of effect was found (among the females only). Environmental temperature seems to have an important influence on later eating attitudes, but the pattern of influence appears to vary across development. Therefore, studies of the mechanisms behind this effect need to consider the role of gender and development, as well as the role of temperature across the period of intrauterine development.

Heterogeneity of the Population of Command Neurons in the Lamprey

The effects of signals transmitted from the brain to the spinal locomotor networks by a population of command neurons are determined by specific functional projections of each individual neuron. To reveal these projections, we used a simple vertebrate model, the lamprey, in which responses of the spinal networks to spikes in single reticulospinal axons were detected by using the spike-triggered averaging of the motoneuronal activity. We found that individual neurons exert a uniform effect on the segmental motor output along the whole extent of their axons. Twenty different patterns of effect, that is, combinations of influences on the segmental motoneuron pools, were found. The widespread projections and heterogeneity of the population of command neurons present a basis for formation of different gross motor synergies.

Surround suppression in primate V1.

We investigated the spatial organization of surround suppression in primate primary visual cortex (V1). We utilized drifting stimuli, configured to extend either from within the classical receptive field (CRF) to surrounding visual space, or from surrounding visual space into the CRF or subdivided to generate direction contrast, to make a detailed examination of the strength, spatial organization, direction dependence, mechanisms, and laminar distribution of surround suppression. Most cells (99/105, 94%) through all cortical layers, exhibited suppression (mean reduction 67%) to uniform stimuli exceeding the CRF, and 43% exhibited a more than 70% reduction. Testing with an annulus revealed two different patterns of surround influence. Some cells (37% of cells), classical surround suppression (CSS) cells exhibited responses to an annulus encroaching on the CRF that were less than the plateau in the spatial summation curve. The majority (63%), center-gated surround suppression (CGSS) cells, showed responses to annuli that equaled or exceeded the plateau in the spatial summation curve. Analysis suggested the CSS mechanism was implemented in all cells while the CGSS mechanism was implemented in varying strength across the sample with the extreme reflected in cells that gave larger responses to annuli than to a center stimulus. Reversing the direction of motion of the portion of the stimulus surrounding the CRF revealed four different patterns of effect: no reduction in the degree of suppression (22% of cells), a reduction in surround suppression (41%), a facilitation of the response above the level to the inner stimulus alone (37%), and a facilitation of the response above that to the inner stimulus alone that also exceeded the values associated with an optimal inner stimulus. The facilitatory effects were only seen for reverse direction interfaces between the central and surrounding stimulus at diameters equal to or more than the CRF size. The zones driving the suppressive influences and the direction contrast facilitation were often spatially heterogeneous and for a number of cells bore strong comparison with the class of behavior reported for surround mechanisms in MT. This suggests a potential role, for example, in extracting information about motion contrast in the representation of the three dimensional structure of moving objects.

Hormone replacement therapy and fractures in older adults.

Estrogen deficiency in women is associated with accelerated bone loss, and estrogen replacement therapy has been proven to be effective in preventing osteoporosis and fractures in postmenopausal women. The introduction of selective estrogen receptor modulators that have an estrogen-like effect on the skeleton but have a different pattern of effects on other tissues may have an important role in the management of osteoporosis in women in the near future. In men, androgen deficiency has been shown to be associated with osteoporosis. Although androgen replacement in hypogonadal men may decrease bone resorption and increase bone mass, long-term placebo-controlled trials are needed to better define the benefits and risks of such therapy before it can be recommended. Sex hormone deficiency is linked to the development of osteoporosis in both women and men. In women, hormonal replacement by estrogen or the newly developed selective estrogen receptor modulators may prevent the development of osteoporosis and its related fractures. In men, there is early evidence that testosterone replacement therapy may enhance bone mass in hypogonadal men.

Nucleus accumbens dopamine and rate of responding: Neurochemical and behavioral studies

It has been suggested that accumbens dopamine (DA) is involved in the process of enabling organisms to expend energy in various situations, including foraging, maze running, and leverpressing. Although accumbens DA depletions impair stimulant self-administration, the effects of these depletions on various food-reinforced operant schedules are highly variable. Accumbens DA depletions have little or no effect on total response output in rats responding on the simplest schedule of food reinforcement (i.e., the fixed ratio 1). In addition, it has been shown clearly that the effects of accumbens DA depletions do not resemble the effects of extinction or prefeeding to reduce food motivation. Over the last several years, our laboratory has investigated the effects of accumbens DA depletions on several schedules, including fixed ratio 1, variable interval 30 sec, fixed interval 30 sec, progressive ratio, and fixed ratio 4, 5, 16, and 64. These schedules generate very different rates of responding, ranging from 300 to 3,000 responses per 30 min. Regression analyses of all these studies indicates a significant linear relation between control rates of responding and the degree of suppression of responding produced by accumbens DA depletions. Schedules that generate relatively low response rates, such as fixed ratio 1 or variable interval 30 sec, are little affected by accumbens DA depletions, yet schedules that generate high response rates (e.g., fixed ratio 64) are severely disrupted. Prefeeding shows different patterns of suppression as a function of response rate. Microanalysis of the temporal characteristics of lever-pressing has shown that accumbens DA depletions produce a response slowing, as measured by the interresponse time; extinction and prefeeding produce a different pattern of effects. These results indicate that accumbens DA depletions do not blunt the reinforcing effects of food, but do suppress responding in a rate-dependent manner. In addition, microdialysis studies have shown that accumbens DA release is positively correlated with leverpressing response rate. Accumbens DA appears to be involved in energy expenditure, behavioral activation, or maintenance of high local rates of responding, which are functions that represent an area of overlap between motor and motivational processes.

Examining the Effects of Divorce on the Academic Achievement of Children

Over the past thirty years, one of the primary concerns facing researchers examining the effects of divorce on the academic achievement of children has been how to best control for socioeconomic status (SES). Prior to 1971, many researchers did not control for SES at all. Herzog and Sudia (1971) argued that adequately controlling for SES was essential for obtaining accurate effects for divorce. In recent years, several social scientists (Cherlin, Kiernan, and Chase-Lansdale, 1995; Allison and Furstenberg, 1989; Milne, 1989) have gone a step further and argued that a predissolution control for SES, when available, is preferable to a postdissolution control for SES. For divorce nearly always causes a drop in the income element of SES. Yet it is not clear whether using a predissolution control for SES really yields effects for divorce that are different than one would obtain if a postdissolution control for SES is used. Using the NELS 1988-92 data set, this study examines whether using a predissolution control for SES yields a different pattern of effects than when a postdissolution control is used (versus when no control for SES is used). The results indicate that using a predissolution control for SES does yield a different pattern of effects than when a postdissolution control is used. The advantages and disadvantages of each means of controlling for SES are discussed.

The Effects of Inhaled Isoparaffins on Locomotor Activity and Operant Performance in Mice

Very little is known qualitatively or quantitatively about the acute central nervous system effects of isoparaffin solvents that are widely used in household and commercial applications. Four isoparaffinic hydrocarbon solvent products differing in predominant carbon number and volatility (ISOPAR-C™, -E™ -G™, -H™) were tested for their acute effects on locomotor activity and operant performance after inhalation exposure in mice. For both measures, concentration–effect curves were obtained for 30-min exposures using a within-subject design. The more volatile products, ISOPAR-C™ and -E™, were as easily vaporized under our conditions as vapors such as toluene and TCE, which have acute effects on human behavior and are abused. ISOPAR-G™ was slowly volatilized and ISOPAR-H™ could not be completely volatilized within our 30-min exposures, suggesting that acute human exposures may be less likely and that it may be more difficult to abuse them. ISOPAR-C™, -E™, and -G™ produced reversible increases in locomotor activity of mice at 4000 and 6000 ppm while ISOPAR-C™ and -E™ produced reversible concentration-dependent decreases in rates of schedule-controlled operant behavior in approximately the same concentration range as they affected locomotor activity. The fact that only locomotor activity increases were observed with these isoparaffins provides evidence that they produce a different pattern of effects than those reported for abused solvents such as toluene and TCE. Further research will be needed to determine if this different pattern of effects on animal behavior between isoparaffins and abused solvents is correlated with a different pattern of acute intoxication and abuse potential in humans.

Modification of cell cycle and viability of TLX5 lymphoma in vitro by sulfoxide-ruthenium compounds and cisplatin detected by flow cytometry

The effects of Na[ trans-RuCl 4(DMSO)Im] (NAMI), Na[ trans-RuCl 4(TMSO)Ind] (TIND) and Na[ trans-RuCl 4(TMSO)Iq] TEQU) were tested in vitro on TLX5 lymphoma cells in comparison to cisplatin by means of the sulforhodamine-B test SRB) for protein content determination, by acridine orange and propidium iodide staining and by means of the bromodeoxyuridine test, for cell cycle modifications. After l h drug exposure with metal-based drugs, TLX5 lymphoma cells require a further 72 h in vitro cultivation to show alteration of cell cycle. Ruthenium compounds show a different pattern of effects: TEQU causes the same dose-dependent cytotoxicity and DNA fragmentation shown by cisplatin, TIND reduces absorbance with the SRB test and slightly increases S and G 2M populations with a time-dependent drug exposure of tumour cells, and NAMI is virtually devoid of any detectable effect. By in vivo bioassay of in vitro treated tumour cells, TIND and TEQU are effective independently of the time of drug exposure of tumour cells, this effect being confirmed by the same cell uptake of ruthenium after l or 4 h treatment, determined by atomic absorption spectroscopy. These data stress the lack of the involvement of direct cytotoxic effects in the potent anti-metastatic action of NAMI.

Skeletal effects of estrogen analogs.

Estrogens clearly have beneficial effects on the skeleton of postmenopausal women. The development of the agents that act like estrogens in the skeleton but may have a different pattern of effect in other tissues, suggests the possibility that tissue-selective estrogens may become important in the management of post-menopausal women in the future, especially those who may be at risk of osteoporosis. Greater understanding of the action of these tissue-selective estrogens will allow the development of a novel compound with profiles that may target more definitively the needs of the postmenopausal population.

Study of the effects of cardiovascular drugs in heart cell cultures

Compounds that produce myocardial pathology in vivo can be separated into two main classes—those that are directly toxic to the myocardium and those that are considered to act by way of an indirect vascular or neurologically based mechanism. An in vitro model of myocardium without nervous or systemic influences can be used to differentiate between direct myocardial cytotoxic effects and indirect cardiac pathology arising in vivo from exaggerated vascular or neural pharmacological effects of a number of drugs. In this study direct-acting cardiotoxic compounds are distinguished from those causing cardiac pathology by indirect mechanisms by their different pattern of effects in chick embryonic myocardial myocyte reaggregates (MMRs) cultures. The toxicity of the direct-acting cardiotoxic drugs allylamine (positive control, 50 μm) and doxorubicin were compared with digoxin and isoprenaline, which show both direct and indirect mechanisms in vivo, and the indirectly acting hydralazine and pinacidil. Changes in spontaneous beating activity (SBA), leakage of lactate dehydrogenase (LDH) and cell morphology by light and transmission electron microscopy were used to assess toxicity. The MMRs were cultured for up to 24 hr in a series of concentrations of the five compounds in the range 0.1 to 10,000 μm. Allylamine, doxorubicin, digoxin and, to a lesser extent, isoprenaline were highly toxic to the MMRs, as shown by alterations in SBA, LDH leakage and cellular morphology. In contrast, hydralazine showed a very mild degree of toxicity at the highest concentrations in the absence of LDH leakage; treatment with pinacidil did not show any evidence of morphological degeneration but did cause a dose-related inhibition of SBA. These results are consistent with the view that doxorubicin and digoxin are directly toxic to myocardial cells and also suggests that this is an important mechanism in vivo for isoprenaline. The absence of a significant degree of toxicity with hydralazine and pinacidil is consistent with an indirect toxic mechanism.

The influence of experimental design: The example of the Brown-Peterson paradigm.

Abstract The results that are found in an experiment may depend upon whether the independent variable is manipulated in a between - subjects or a within - subjects fashion. This is illustrated here using the Brown - Peterson short - term temporory distractor paradigm. The traditional finding of rapid memory loss as a function of retention interval was found only when retention interval was manipulated within subjects. No effects of retention interval was found when retention interval was manipulated between subjects. Perhaps the most basic distinction among kinds of experimental design is that between within - subject (repeated - measures) and between - subject (separate - group) designs. Within - subjects designs have long been popular in experimental psychology, and they have become even more widely used in recent decades (Poulton, 1982). In some domains, this may reflect greater ecological validity for within - subjects designs insofar as people may experience a number of levels of a particular variable in everyday life (Greenwald, 1976). However, a major reason for the popularity of within - subjects designs is that they are more statistically powerful than between - subjects designs. In memory research, several variables of current interest have been shown to yield different patterns of effects in within - subjects and between - subjects experiments. The effects of stimulus generation (Begg & Snider, 1987; Slamecka & Katsaiti, 1987), imagery bizarreness (McDaniel & Einstein, 1986), levels of processing (Challis & Brodbeck, 1992; Thapar & Greene, 1994), and presentation modality (Greene, 1989) may each be modified by the nature of the experimental design. The purpose of this study is to demonstrate that even the most classic findings of memory research are not necessarily immune to the effects of design. One of the most heavily studied memory paradigms is the Brown - Peterson (or distractor) short - term memory task (for a review, see Greene, 1992). On each trial, subjects are given a short list of items and then engage in a rehearsal - preventing activity during the retention interval. At the conclusion of the retention interval, subjects are asked for recall of the items (usually in order). The classic finding (first discovered by Daniels, 1895, and later reported by Peterson & Peterson, 1959) is that recall is quite accurate at short retention intervals but drops rapidly, reaching asymptote when the retention interval is approximately 15 - 25 s. Two aspects of the procedure of Daniels (1895) and Peterson and Peterson (1959) that have been followed by most later researchers are that each subject goes through multiple trials and that the duration of the retention interval is varied randomly within subjects. A rare exception to this pattern is an experiment by Turvey, Brick, and Osborn (1970), who performed an experiment in which, for the first four trials, each subject experienced only one duration of the retention interval. Different groups underwent 5, 10, 15, 20, or 25 s of distraction on each trial. An examination of Turvey et al.'s (1970) data reveals no tendency for longer retention intervals to lead to poorer memory; in fact, there was a slight tendency in the opposite direction. Perhaps because this experiment was not carried out to study the effects of retention interval, this aspect of the data was given little attention by Turvey et al. (1970) and has been rarely discussed in subsequent studies. Turvey et al.'s (1970) data are reminiscent of Keppel and Underwood's (1962) finding that performance on the first trial of a Brown - Peterson task was unaffected by the duration of the retention interval. Keppel and Underwood's (1962) data are often dismissed as being uninterpretable due to ceiling effects on first - trial performance (see, e.g., Baddeley, 1990, p. 48; Crowder, 1989, p. 278). Turvey et al.'s (1970) results suggest that null effects of retention interval are not necessarily always due to ceiling effects. …

The contribution of ischaemia and deformation to the conduction block generated by compression of the cat sciatic nerve

The pattern of conduction block induced in cat peripheral nerve by compression has been investigated electrophysiologically by recording unitary action potentials. A degree of compression, associated with chronic compression disorders in man, was applied to the cat sciatic nerve and resulted in a conduction block typified by early failure of the slow conducting myelinated axons. By contrast, a greater degree of compression, a degree more likely to result in acute compression lesions, produced a different pattern of effect, inducing early conduction failure in the fast conducting myelinated axons. These results are related to earlier studies which have shown that nerve deformation during compression has a differential action upon fast myelinated axons, while nerve ischaemia has a differential action upon slow myelinated axons.

A comparison of women's and men's leisure time: Subtle effects of the double day

Abstract In this article women's and men's leisure time were examined using the 1981 Study of Time Use (Juster, Hill, Stafford, & Parsons, 1983). Gender differences in total leisure time, types of leisure activities, and the effects of household labor time and paid labor time on women's and men's leisure time were assessed. Although there were few significant differences in women's and men's leisure time expenditures, some differences in the determinants of leisure were found. Although household labor time affects women's and men's leisure time in the same way, the impact of paid labor time on leisure time varies by gender and by type of leisure. Paid labor time has a stronger effect on women's nondomestic leisure time than on men's, whereas the reverse is true for domestic leisure time. The different types of leisure activities in which women and men engage, and their different time expenditures for paid work and housework, combined to produce these different patterns of effects.

Apomorphine and amphetamine produce differential effects on the speed and success of reaction time responding in the rat

Apomorphine, a nonselective, direct-acting dopamine agonist, and amphetamine, a nonselective indirect-acting dopamine agonist, were compared for their effects on the reaction time response in rats. Animals were shaped to release a lever in response to an auditory/visual stimulus to avoid mild foot shock. The characteristics of the reaction time response of primary interest were percent successful avoidance and response latency. Apomorphine (0, 1, and 5 mg/kg, IP) significantly decreased successful avoidance, but had no effect on response latencies. Thus, the decrease in successful avoidance was not a direct result of longer latencies. Amphetamine (0, 0.5, and 1 mg/kg, IP) produced a different pattern of effects on the reaction time response. Successful avoidance was not affected by amphetamine treatment. However, response latencies were dose-dependently decreased in response to amphetamine. These results demonstrate that dopamine receptor stimulation by different dopamine agonists produces a different pattern of effects on the characteristics of the reaction time response. In addition, these results demonstrate that successful avoidance can be modulated independently of response latencies.