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Product-line strategy should be developed in relation to markets. This article focuses on designing product-line strategy in relation to four purchaser types: (1) traditional purchasers, (2) motivated purchasers, (3) HMO-type purchasers, and (4) PPO-type purchasers. In many cases, product-line strategy may have to adopt various combinations of the above.
AIMS: To characterize the reinforcing, subjective and psychomotor effects of sevoflurane, a volatile anesthetic, across a range of subanesthetic concentrations in non-drug-abusing humans. In addition, a concentration of nitrous oxide was included in the design in order to compare and contrast behavioral effects of a gaseous to a volatile anesthesic. DESIGN: Repeated measures, double-blind, placebo control experiment. SETTING: Human psychopharmacology laboratory. PARTICIPANTS: Fourteen moderate-drinking healthy volunteers. INTERVENTION: In each of four sessions, subjects first sampled placebo-oxygen and an active drug (end-tidal concentrations of 0.2, 0.4, 0.6% sevoflurane and 30% nitrous oxide in oxygen) and then chose between the two MEASUREMENTS: Mood and psychomotor performance during the sampling trials, and choice of drug or placebo-oxygen during choice trial. FINDINGS: Nitrous oxide was chosen by 71% of the subjects, and 0.2, 0.4 and 0.6% sevoflurane were chosen by 50%, 57% and 50% of the subjects, respectively. Neither drug was chosen at levels that exceeded that of chance. Sevoflurane and nitrous oxide both impaired psychomotor performance and produced changes in mood. There were several differences in subjective effects between sevoflurane and nitrous oxide at concentrations which were considered to be equivalent in anesthetic effect. Finally, although sevoflurane did not function as a reinforcer in the majority of individuals tested, there was evidence that sevoflurane functioned as a reinforcer in some volunteers: subjects who chose to inhale sevoflurane over placebo-oxygen tended to report a positive spectrum of subjective effects during the sevoflurane sampling trial, relative to those subjects who chose placebo-oxygen over sevoflurane. CONCLUSIONS: Although sevoflurane did not function as a reinforcer in the majority of subjects tested, the correspondence between positive subjective effects of sevoflurane and subsequent sevoflurane choice suggests that the volatile anesthetic drug can function as a reinforcer in some moderate drinkers.
To develop a screening method for psychic dependence liability of the drugs, morphine- and cocaine-directed drinking behavior was studied in mice. Using automatic drinkometer the intake of drug solution from the paired sucking tube connected to tap water and/or drug solution was estimated. The drinking pattern showed a diurnal rhythm and large portion of the total intake was done during dark period. When the animals were forcedly given drugs as drinking solution total intake and the gain of body weight was suppressed in proportion to the concentration of the drugs. In the choice test between tap water and drug solution, mice can distinguish the concentration of drug solution and avoid it in high concentrations. Animals experienced drug solution before the choice test showed a tendency to intake more drug solution than the untreated control animals depending on the length of pretreatment. Pretreatment of the animals with twice daily injections of the drugs failed to develop high grade of preference to drug solution in the succeeding choice test. Thus, the positive reinforcing properties of morphine and cocaine was demonstrated in mice and the validity of this animal species for the screening of the drugs of psychic dependence was suggested.
Data are reported on the sexual behavior of a random sample of 2171 youth, 16-20 years old, in two locations in the U.K. Lower bound prevalence estimates for a range of specific sex acts are presented with discussion of the likely biases in the data. Given concerns about the spread of HIV through the heterosexual population, emphasis is given to the nontrivial estimates of a number of potential transmission risk behaviors, in particular, heterosexual anal penetration. Data are also presented suggesting that experience with particular sexual acts is associated with maintenance of a desire to do these acts in the future. The implications of these findings for health education policy are discussed.
The cerebellum is critically involved in temporal processes in the millisecond range and may be involved in longer time estimations (i.e. in the seconds range). Estimates in the millisecond range are impaired after developmentally induced cerebellar alterations, however, little is known about the effects of similar alterations on longer timing performance. Appropriately timed DFMO treatment reliably causes cerebellar stunting in rats, however, its effects on temporal estimation performance are unknown. Here, male and female Sprague-Dawley rats were treated with subcutaneous injections of 500 mg/kg DFMO on postnatal days 5-12, causing a 10% cerebellar weight reduction at adulthood. As adults, subjects were tested under one of two paradigms - a differential reinforcement of low response rate (DRL) task requiring that subjects withhold a lever press response for 10-14 s or a temporal response differentiation (TRD) task requiring that subjects maintain a lever press response for 10-14 s. Training and steady-state performance of the DRL and TRD tasks were not significantly altered by DFMO treatment. Performance after acute challenges with two dopaminergic agonists (2.00-7.50 mg/kg methylphenidate and 0.10-1.00 mg/kg d-amphetamine) was measured after which all subjects underwent behavioral extinction. Generally, performance after methylphenidate and d-amphetamine was similar in control and DFMO-treated rats and DFMO treatment had no differential effects on performance during extinction. These results support findings from an earlier study [Ferguson SA, Paule MG, Holson RR. Neonatal dexamethasoneon day 7 in rats causes behavioral alterations reflective of hippocampal, but not cerebellar, deficits. Neurotoxicol Teratol, 2001; 23:57-69] indicating that developmental cerebellar stunting has few effects on time estimation within the range of seconds.
Effective procedures are needed to prevent the substantial increases in adiposity that have been occurring among children and adults. Behavioral change may occur as a result of changes in variables that mediate interventions. These mediating variables have typically come from the theories or models used to understand behavior. Seven categories of theories and models are reviewed to define the concepts and to identify the motivational mechanism(s), the resources that a person needs for change, the processes by which behavioral change is likely to occur, and the procedures necessary to promote change. Although each model has something to offer obesity prevention, the early promise can be achieved only with substantial additional research in which these models are applied to diet and physical activity in regard to obesity. The most promising avenues for such research seem to be using the latest variants of the Theory of Planned Behavior and Social Ecology. Synergy may be achieved by taking the most promising concepts from each model and integrating them for use with specific populations. Biology-based steps in an eating or physical activity event are identified, and research issues are suggested to integrate behavioral and biological approaches to understanding eating and physical activity behaviors. Social marketing procedures have much to offer in terms of organizing and strategizing behavioral change programs to incorporate these theoretical ideas. More research is needed to assess the true potential for these models to contribute to our understanding of obesity-related diet and physical activity practices, and in turn, to obesity prevention.
We examine the impact of orphanhood on children's school enrollment in 10 sub-Saharan African countries. Although poorer children in Africa are less likely to attend school, the lower enrollment of orphans is not accounted for solely by their poverty. We find that orphans are less likely to be enrolled than are nonorphans with whom they live. Consistent with Hamilton's rule, the theory that the closeness of biological ties governs altruistic behavior, outcomes for orphans depend on the relatedness of orphans to their household heads. The lower enrollment of orphans is largely explained by the greater tendency of orphans to live with distant relatives or unrelated caregivers.
Reinforcing effects of intraperitoneally (IP) administered substance P (SP1-11), its amino-terminal fragment SP1-7 (SPN) and an analog of the carboxy terminus (pGlu6-SP6-11: SPC) were studied in rats. Two conditioned place preference paradigms were used. After three pairings of the drug with a certain environment the effect of the treatment was evaluated in the drug-free state during a test trial. The reinforcing effects of SP (37 nmol) and the equimolar dose of SPC were expressed by a significant increase in the amount of time the animals spent in the treatment environment. Other doses of SP (3.7 and 185 nmol) and SPC (7.4 and 185 nmol) and none of the doses of SPN (37, 185, 370 nmol) influenced the place preference behavior of the rats. The reinforcing effects of SP parallel the known facilitating effects of peripherally administered SP on memory. The amino acids that encode the reinforcing effects of SP may lie within the C-terminal sequence of the SP molecule.
BACKGROUND: Our previous work has shown genetic variation in the human choline transporter gene (CHT1) to be associated with depressive symptoms and autonomic cardiac (cholinergic) dysregulation. Here, functional magnetic resonance imaging (fMRI) was used to examine the relation between a single nucleotide polymorphism (SNP) in CHT1 on regional brain reactivity relevant to autonomic (cholinergic) function. METHODS: Thirty-two participants of European ancestry (18 men, 14 women; age: 33-54 years) completed an fMRI protocol using corticolimbic reactivity and prefrontal inhibitory control paradigms. Resting cholinergic function, as measured by heart rate variability (HRV), was quantified from electrocardiogram. Subjects were genotyped for a CHT1 G/T SNP. RESULTS: GG homozygotes had greater right (R) dorsal amygdala (p < .008), bilateral anterior cingulate (p < .009), and R caudate reactivity (p < .015) than T-allele carriers. Heart rate variability was related to R frontal cortex (Brodmann Areas 6, 9, and 46), R hippocampal formation, bilateral caudate, and bilateral anterior cingulate reactivity (p's < .007). CONCLUSIONS: CHT1 variation is related to differences in a distributed corticolimbic circuitry mediating behavioral and physiologic arousal. These relations may contribute to a biological mechanism by which genetic variation in cholinergic neurotransmission affects cognition, mood, and autonomic cardiac function.
Methylphenidate is commonly prescribed for children in order to improve attentional aspects of their behavior. However, resultant long-term academic improvement in these children is negligible. To investigate this discrepancy, a reaction time paradigm was utilized with 10 males and 2 females (mean age was 9.8 years; SD, 1.6 years) diagnosed as having an attentional deficit disorder. Using a double-blind procedure with methylphenidate and a placebo, a decrease in simple reaction time was found in the medication condition. However, no drug effect was found on decision times using a choice reaction time task. It was concluded that methylphenidate and perhaps other stimulant medications affect attentional processes in hyperactive youth but may not affect those higher cortical processes required to make long-term academic gains.
Bangladesh has experienced a substantial decline in fertility that has been achieved by means of a large increase in the use of modern methods of contraception. As contraceptive prevalence increases, aspects of contraceptive-use dynamics, including reasons for discontinuation and behavior after discontinuation, become important influences on fertility. This report uses calendar data from the 1993-94 Bangladesh Demographic and Health Survey to examine contraceptive behavior following discontinuation of modern-method use. The individual-level characteristics found to influence switching behavior include the method used, method-related difficulties with previous contraceptive use, and education. A large amount of unexplained variation in switching rates remains, however, largely at the individual level, but also at the community level for certain types of transition.
Studies report that women have diverging preferences for physician gender. The present study explores some aspects of how women's preferences for physician gender are formed. Using data from a postal survey among Norwegian women, the association between preferences for physician gender and women's priorities regarding physician behavior is examined. Women who, in particular, value their physicians' democratic attitudes tend to prefer female physicians, in contrast to those who prefer a more dominating physician role. Surprisingly, women who especially emphasize the caring qualities of their physicians, do not have strong preferences for a female physician.
BACKGROUND: Impairments in social behaviors are highly disabling symptoms of autism, schizophrenia, and other psychiatric disorders. Mouse model systems are useful for identifying the many genes and environmental factors likely to affect complex behaviors, such as sociability (the tendency to seek social interaction). To progress toward developing such a model system, we tested the hypothesis that C57BL/6J inbred mice show higher levels of sociability than BALB/cJ inbred mice. METHODS: Mice tested for sociability were 4- and 9-week-old, male and female C57BL/6J and BALB/cJ mice. On 2 consecutive days, the sociability of each test mouse toward an unfamiliar 4-week-old DBA/2J stimulus mouse was assessed with a social choice paradigm conducted in a three-chambered apparatus. Measures of sociability included the time that the test mouse spent near versus far from the stimulus mouse, the time spent directly sniffing the stimulus mouse, and the time spent in contact between test and stimulus mice in a free interaction. RESULTS: C57BL/6J mice showed higher levels of sociability than BALB/cJ mice overall in each of these measures. CONCLUSIONS: We propose that C57BL/6J and BALB/cJ mice will be a useful mouse model system for future genetic and neurobiological studies of sociability.
Clients often engage in behavior that involves risk. Consequences of this behavior are sometimes harmful, but not always. Many times clients' views of the risks they are taking are often based on personal decisions they have made about their own health. People who take risks are frequently quite knowledgeable. The author uses case studies to examine the concept of risk. The author posits that teaching plans must account for the risks that clients take. Teaching plans should reflect that risks/benefits need to be discussed. Teaching should reflect respect for patient choices. An open discussion with the client that reflects what is really happening in the client's everyday life is of far more value than scanty, often glossed-over reports clients are accustomed to giving health professionals.
BACKGROUND: Non-random mating affects population variation for substance use and dependence. Developmentally, mate selection leading to positive spousal correlations for genetic similarity may result in increased risk for substance use and misuse in offspring. Mate selection varies by cohort and thus, assortative mating in one generation may produce marked changes in rates of substance use in the next. We aim to clarify the mechanisms contributing to spousal similarity for cigarette smoking and alcohol consumption. METHODS: Using data from female twins and their male spouses, we fit univariate and bivariate twin models to examine the contribution of primary assortative mating and reciprocal marital interaction to spousal resemblance for regular cigarette smoking and nicotine dependence, and for regular alcohol use and alcohol dependence. RESULTS: We found that assortative mating significantly influenced regular smoking, regular alcohol use, nicotine dependence and alcohol dependence. The bivariate models for cigarette smoking and alcohol consumption also highlighted the importance of primary assortative mating on all stages of cigarette smoking and alcohol consumption, with additional evidence for assortative mating across the two stages of alcohol consumption. CONCLUSIONS: Women who regularly used, and subsequently were dependent on cigarettes or alcohol were more likely to marry men with similar behaviors. After mate selection had occurred, one partner's cigarette or alcohol involvement did not significantly modify the other partner's involvement with these psychoactive substances.
This study investigated lateral biases in nipple preferences, maternal cradling, carrying, and retrieval in 41 rhesus macaque (Macaca mulatta) mother-infant dyads living in two captive social groups. Observations were made during the first 6 weeks of infant life using a combination of scan sampling and ad-libitum sampling techniques. Infants exhibited a significant left-nipple preference in the first weeks of life but the bias decreased with infant age. Mothers showed a left-arm bias in carrying their infants but no significant lateral bias in cradling or retrieval. Our results suggest that the left-side cradling bias reported in studies of humans and some other primates reflects a bias in the infant's nipple preference rather than in maternal behavior. The infants' preference for the left nipple is consistent with both Salk's (1960) heartbeat hypothesis and with more recent hypotheses linking this lateral bias with brain asymmetry and hemispheric specialization for mother-infant communication.
Conspicuous swellings of the perineal skin can be observed in females of many catharrine primate species particularly during the middle stages of the ovarian cycle. The functional significance of this trait remains poorly understood. Recently, two hypotheses, the "reliable indicator" hypothesis and the "graded signal" hypothesis that take into account not only the pattern but also the exaggerated size of sexual swellings, have gained attention. Here we test several predictions made by these hypotheses by combining (i) direct size measures (from video captures) of female sexual swellings with (ii) urinary hormone data to indicate timing of ovulation through enzyme immunoassay measurements of estrone conjugates and pregnanediol glucuronide (PdG) and (iii) behavioral observations of male mating efforts throughout 36 ovulatory cycles in 12 wild chimpanzees. We are able to show that (i) even within the traditionally defined maximum swelling period, further slight increases in swelling size indicate approaching ovulation, and (ii) that male mating interest changes according to the changes in swelling size. Furthermore, absolute swelling size during the periovulatory period increases and the alpha male associates more with females as the number of cycles to conception decreases. Finally, when having the choice between several "maximally" tumescent females, the alpha male prefers the female that is in the fertile phase of her cycle rather than that with the biggest swelling at that time. Thus, most of our findings are in line with the predictions of the graded signal hypothesis while none of them would support the reliable indicator hypothesis.
Large sex differences in children's toy preferences are attributed to gender group identification and social learning. The proposal outlined in this paper is that contemporary conceptual categories of "masculine" or "feminine" toys are also influenced by evolved perceptual categories of male-preferred and female-preferred objects. Research on children exposed prenatally to atypical levels of androgens and research on typically developing infants suggest sex-dimorphic preferences exist for object features, such as movement or color/form. The evolution and neurobiology of mammalian visual processing--and recent findings on sex-dimorphic toy preferences in nonhuman primates--suggest further that an innate bias for processing object movement or color/form may contribute to behaviors with differential adaptive significance for males and females. In this way, preferences for objects such as toys may indicate a biological preparedness for a "masculine" or "feminine" gender role-one that develops more fully as early perceptual preferences are coupled with object experiences imposed by contemporary gender socialization.