Why some people smoke and others do not: New perspectives.

Because initial reinforcement consequences set the stage for subsequent nicotine use, elucidation of the contribution of environmental and inherited factors is crucial to an understanding of nicotine dependence as well as of individual differences in susceptibility to cigarette smoking. A review of some recent animal research and laboratory studies of smokers and never-smokers suggests that vulnerability to nicotine dependence is related to high initial sensitivity to nicotine and that the development of acute pharmacodynamic tolerance in these individuals, particularly to effects of nicotine that are toxic or aversive, may be an adaptation for protecting homeostasis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effet des stimuli écologiques et des programmes de renforcement sur les comportements exploratoires et ludiques de l'enfant.

Analyzed functional relationships between children's exploratory and play behaviors, and stimuli elicited by a novel object in a familiar setting. In Exp I, a wooden duck was presented to 4 groups of 3–5 yr olds. Manipulation of the duck's tail elicited, according to groups, tactile–visual, tactile–auditory, or tactile–visual–auditory stimulations. In Exp II, an intermittent schedule of reinforcement was implemented to examine variations of responses in the tactile–auditory condition. Results indicate variations in the manipulatory response and in the 3 classes of observed behaviors. Tactile–visual–auditory stimulations elicited a maximum of behaviors associated with the novel object and an exponential decrease of manipulatory responses after 2 sessions. The intermittent schedule, in the tactile–auditory condition, elicited behaviors relatively similar to those observed in the tactile–visual–auditory condition. Ecological stimuli affected differently the operant response, as well as other classes of behaviors. The difficulty, and probably the uselessness, of a differentiation between exploration and play is underlined in the discussion. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Genome-wide linkage analysis for smoking-related regions, with replication in two ethnically diverse populations.

As part of the Genetic Epidemiology Network of Arteriopathy, hypertensive sibships were collected and smoking behavior recorded. Using an affected sibpair design and genome-wide microsatellite data markers ( approximately 10 cM coverage), we identified 214 non-Hispanic White sibships (502 sibpairs) from Rochester, Minnesota (M (age) [SD] = 55.68 years [10.56]) and 206 Black sibships (376 sibpairs) from Jackson, Mississippi (M (age) = 57.97 [8.94]), who had smoked for at least 3 years, and performed nonparametric linkage analysis using GENEHUNTER. We found evidence of linkage on chromosome 3 in both Whites (LOD = 1.76@109 cM) and Blacks (LOD = 2.03@122 cM). Each of these peaks had a secondary smaller peak at 140-147 cM that was statistically suggestive only in the Black sample (LOD = 1.4). The peak for the combined samples was suggestive of strong linkage (LOD = 3.24@124 cM). Additional suggestive peaks (LOD>1.3) were found in the White (chromosomes 8 [26 cM] and 19 [36 cM]) and Black sibships (chromosome 10 [153 cM]) but did not overlap with corresponding regions in the other ethnic group. This is the first study to identify a chromosomal region that has replicate evidence of linkage to smoking in two independent samples of similar size differing both geographically and ethnically. The gene for serotonin receptor 1F (HTR1F) is located in the region of the chromosome 3 linkage signal, representing at least one potential candidate gene. Fine mapping may well provide useful new information about genetic factors underlying nicotine dependence.     

Performance analysis of a dynamic phenomenological controller for a pellet cooling process

The cooling zone of an induration furnace exhibits a nonlinear dynamic behavior in addition to a strong coupling between output pressure and temperature. Simulation studies show that linear controller performance is unacceptable from an industrial point of view. In order to obtain adequate performance on a wide operating range, a nonlinear predictive controller (NLMPC) based on a phenomenological process model is proposed. Since the furnace simulation model shows that the equipment behaves as a Hammerstein model, a variable change is performed and a linear model predictive controller (MPC) is developed for the cooling zone. Both controllers are tested for set-point changes and disturbance rejection and give relatively similar performances. It is concluded that for processes having structured nonlinearities, as the cooling zone considered here, linear MPC should be preferred to NLMPC since the computation time is far less demanding and the industrial implementation easier.     

Differential prevalence of cigarette smoking in patients with schizophrenic vs mood disorders

Reactive oxygen species (ROS) and reactive metabolic intermediates generated from various chemical carcinogens are known to play an important role in cell damage and in the initiation and progression of carcinogenesis. Many radical scavengers, interestingly naturally occuring antioxidants have been found to be effective in inhibiting the induction of carcinogenesis by a wide variety of chemical carcinogens. Studies have also indicated that various spice principles form an important group as antioxidants. In the present study our goal was to investigate whether piperine an pungent principle of black and long peppers was able to inhibit or reduce the oxidative changes induced by chemical carcinogens in rat intestinal model. Carcinogenesis was initiated in intestinal lumen of male rats with 7,12,dimethyl benzanthracene, dimethyl amino-methyl azobenzene and 3-methyl cholenthrene. Oxidative alterations were assessed by determining thiobarbituric reactive substances, mainly malonaldehyde (as a measure of lipid peroxidation), thiol status and expression of gamma-GT and Na+-K+-ATPase activity in intestinal mucosa. Data indicated that carcinogens treatment induced GSH depletion with substantial increase in thiobarbituric reactive substances and enzyme activities. Piperine treatment with carcinogens resulted in inhibition of thiobarbituric reactive substances. It mediated a significant increase in the GSH levels and restoration in gamma-GT and Na+-K+-ATPase activity. The studies thus indicate a protective role of piperine against the oxidative alterations by carcinogens. It may be suggested that piperine modulates the oxidative changes by inhibiting lipid peroxidation and mediating enhanced synthesis or transport of GSH thereby replenishing thiol redox.     

Comparing ICP variants on real-world data sets

Many modern sensors used for mapping produce 3D point clouds, which are typically registered together using the iterative closest point (ICP) algorithm. Because ICP has many variants whose performances depend on the environment and the sensor, hundreds of variations have been published. However, no comparison frameworks are available, leading to an arduous selection of an appropriate variant for particular experimental conditions. The first contribution of this paper consists of a protocol that allows for a comparison between ICP variants, taking into account a broad range of inputs. The second contribution is an open-source ICP library, which is fast enough to be usable in multiple real-world applications, while being modular enough to ease comparison of multiple solutions. This paper presents two examples of these field applications. The last contribution is the comparison of two baseline ICP variants using data sets that cover a rich variety of environments. Besides demonstrating the need for improved ICP methods for natural, unstructured and information-deprived environments, these baseline variants also provide a solid basis to which novel solutions could be compared. The combination of our protocol, software, and baseline results demonstrate convincingly how open-source software can push forward the research in mapping and navigation.     

Introduction to the featured section: Genetic research on smoking.

Presents an overview of the featured section concerning genetic research and smoking. A better understanding of the genetics of smoking should lead to more precise identification of individuals at risk and also greatly facilitate drug discovery programs, to identify novel agents that can mimic or antagonize nicotine effects. Developments in genetic research have considerable potential for enhancing smoking prevention and treatment in the future. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Place of birth and dietary intake in Ontario. I. Energy, fat, cholesterol, carbohydrate, fiber, and alcohol

The best predictor of poor or suboptimum outcome from pulmonary thromboendarterectomy (PTE) is insufficient relief of obstruction, especially in the lower lobes. The aim of this study is to emphasize that the use of video-assisted angioscopy may increase the quality of PTE and thus improve outcome. PTE included a median sternotomy, intrapericardial dissection limited to the superior vena cava, institution of cardiopulmonary bypass, deep hypothermia and sequential circulatory arrest periods. PTE was always bilateral and performed through two separate arteriotomies of both main intrapericardial pulmonary arteries. A rigid 5 mm angioscope connected to a video camera was introduced through the arteriotomy into the lumen to increase the visibility and perform the video-assisted endarterectomies of all obstructed segmental branches, including normally inaccessible anterior segmental branches. Between January 1996 and December 1997, 48 patients with severe postembolic pulmonary hypertension had PTE. Patients were in New York Heart Association (NYHA) class II (n = 2), III (n = 28) or IV (n = 18) with the following hemodynamics: mean pulmonary arterial pressure (PAP) 53 +/- 13 mmHg, cardiac index 2.16 +/- 0.5 L/min/m2, pulmonary vascular resistances (PVR): 1,152 +/- 414 dyne.s-1.cm-5. Six patients died from alveolar hemorrhage (n = 1), high residual pulmonary pressure and rethrombosis (n = 4) and hypoxic cardiac arrest (n = 1). The functional outcome in surviving patients was as follows: (NYHA) class I (n = 24), II (n = 16) or III (n = 2) with improved hemodynamics: mean pulmonary arterial pressure: 30 +/- 9 mmHg, cardiac index: 2.78 +/- 0.5 L/min/m2, pulmonary vascular resistances (PVR): 484 +/- 159 dynes.s-1.cm-5. Video-assisted angioscopy allows much improved quality and degree of pulmonary endarterectomy. This expands the indications to include patients with previously inaccessible distal disease and candidates for heart-lung transplantation.     

Temporal and content variations as determinants of infants' visual control of verbal stimulations.

20 93–119 day old infants were presented with utterances varying in content or temporal structure that were contingent on fixation on a visual target. Treatment A consisted of utterances of equal duration and continually varying content. Treatment B consisted of utterances of slightly variable duration (temporal runs) and continually varying content. Treatment C included utterances organized in temporal runs and was composed of partial content variations (content runs). For Group AB, each A trial alternated with a B trial 4 times. For Group AC, each A trial alternated with a C trial 4 times. Half of the Ss in each group received Treatment A as their 1st trial; half of the Ss in Group AB received Treatment B; and half of the Ss in Group AC received Treatment C as their 1st trial. Group AB Ss showed a longer total fixation time than those of Group AC, with a more homogeneous distribution of number of fixations across treatments. Mean length of fixations was longer for Treatment A than B in Group AB, whereas Group AC showed a longer mean length of fixation for Treatment C relative to Treatment A. Those with Treatment B or C as their 1st trial looked more frequently at the target, and their decrease in looking time over trials showed a linear trend, whereas Ss with Treatment A at first displayed irregular decreases. These differences between groups and presentation orders suggest that 3-mo-old infants are sensitive to differences in linguistic material. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral medicine: The contribution of the experimental analysis of behavior to medical care.

There has been a great increase in research and clinical activity using psychological methods and procedures for understanding and modifying patterns of behavior that affect physical health. The term "behavioral medicine" has come into use to describe some of these activities. The present article reviews the contribution of the experimental behavioral sciences in the understanding and treatment of medical disorders and disease and examines some of the implications of the new field for psychology. Current definitions, which emphasize either a biopsychosocial or a behavioral framework, are discussed. Major themes in clinical behavioral medicine are identified, including the modification of overt behavior or physiological responses that constitute problems in their own right, the modification of behavior of health care providers, the improvement of adherence to prescribed treatment, and the modification of behavior or responses that constitute risk factors for disease. (95 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)