Solar Aluminum Production by Vacuum Carbothermal Reduction of Alumina—Thermodynamic and Experimental Analyses

Thermochemical equilibrium calculations indicate the possibility of significantly lowering the onset temperature of aluminum vapor formation via carbothermal reduction of Al2O3 by decreasing the total pressure, enabling its vacuum distillation while bypassing the formation of undesired by-products Al2O, Al4C3, and Al-oxycarbides. Furthermore, the use of concentrated solar energy as the source of high-temperature process heat offers considerable energy savings and reduced concomitant CO2 emissions. When the reducing agent is derived from a biomass source, the solar-driven carbothermal reduction is CO2 neutral. Exploratory experimental runs using a solar reactor were carried out at temperatures in the range 1300K to 2000K (1027°C to 1727°C) and with total pressures in the range 3.5 to 12 millibar, with reactants Al2O3 and biocharcoal directly exposed to simulated high-flux solar irradiation, yielding up to 19pct Al by the condensation of product gases, accompanied by the formation of Al4C3 and Al4O4C within the crucible. Based on the measured CO generation, integrated over the duration of the experimental run, the reaction extent reached 55pct at 2000K (1727°C

Serotonin Transporter Promoter Polymorphism Genotype Is Associated With Behavioral Disinhibition and Negative Affect in Children of Alcoholics

Serotonergic (5-HT) dysfunction has been implicated in the etiology of both behavioral disinhibition (BD) and negative affect (NA). This work extends our previous finding of relationships between whole blood 5-HT and both BD and NA in pubescent, but not prepubescent, children of alcoholics and continues examination of a hypothesized role of 5-HT dysfunction in alcoholism risk. The long and short (L and S) variants of the 5-HT transporter gene-linked polymorphic region (5-HTTLPR) are responsible for differing transcriptional efficiencies in 5-HT uptake. Although associations have been found between the SS 5-HTTLPR genotype and severe alcoholism and neuroticism, recent reports describe relationships between the LL genotype and both low level of response to alcohol and alcoholism diagnosis and a predominance of the LL genotype in early-onset alcoholics. Methods : This report is from an ongoing prospective study of the development of risk for alcoholism and other problematic outcomes in a sample of families classified by father's alcoholism subtype. This study examines relationships between 5-HTTLPR genotype and both child BD (Child Behavior Checklist Aggressive Behavior) and NA (Child Behavior Checklist Anxious/Depressed) in offspring from 47 families. Results : Results showed significantly higher levels of BD and NA in the 16 children with the LL genotype than the 46 SS or SL children. Conclusions : Behaviors of undercontrol, which occur at increased rates in children of alcoholics, may be genetically influenced through the regulation of the 5-HT transporter. Due to the small sample size and the preliminary nature of our findings, replication is necessary.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65855/1/j.1530-0277.2001.tb02302.x.pd

Serotonergic Contribution to Boys' Behavioral Regulation

Animal and human adult studies reveal a contribution of serotonin to behavior regulation. Whether these findings apply to children is unclear. The present study investigated serotonergic functioning in boys with a history of behavior regulation difficulties through a double-blind, acute tryptophan supplementation procedure.Participants were 23 boys (age 10 years) with a history of elevated physical aggression, recruited from a community sample. Eleven were given a chocolate milkshake supplemented with 500 mg tryptophan, and 12 received a chocolate milkshake without tryptophan. Boys engaged in a competitive reaction time game against a fictitious opponent, which assessed response to provocation, impulsivity, perspective taking, and sharing. Impulsivity was further assessed through a Go/No-Go paradigm. A computerized emotion recognition task and a staged instrumental help incident were also administered.Boys, regardless of group, responded similarly to high provocation by the fictitious opponent. However, boys in the tryptophan group adjusted their level of responding optimally as a function of the level of provocation, whereas boys in the control group significantly decreased their level of responding towards the end of the competition. Boys in the tryptophan group tended to show greater perspective taking, tended to better distinguish facial expressions of fear and happiness, and tended to provide greater instrumental help to the experimenter.The present study provides initial evidence for the feasibility of acute tryptophan supplementation in children and some effect of tryptophan supplementation on children's behaviors. Further studies are warranted to explore the potential impact of increased serotonergic functioning on boys' dominant and affiliative behaviors

Diseño y simulación de una rectenna para cosechar energía electromagnética a 2.4 GHz

Trabajo de InvestigaciónSe realizó el diseño y la simulación de una antena rectificadora con tecnología microcinta a 2.4 GHz junto con un filtro pasa-banda chebyshev de octavo orden y un rectificador de onda completa tipo puente de diodos con el fin de obtener la conversión de ondas electromagneticas a una señal DC.INTRODUCCIÓN 1. GENERALIDADES 2. RECTENNAS Y HERRMANIENTAS DE SIMULACIÓN 3. DISEÑO DE UNA ANTENA RECTIFICADORA A 2.4 GHz 4. DISEÑO Y SIMULACIÓN DE LA ANTENA RECTIFICADORA 5. CONCLUSIONES 6. RECOMENDACIONES Y TRABAJOS FUTUROS 7. ESTRATEGIAS DE COMUNICACIÓNPregradoIngeniero Electrónic

Epidemiologic and clinical updates on impulse control disorders: a critical review

The article reviews the current knowledge about the impulse control disorders (ICDs) with specific emphasis on epidemiological and pharmacological advances. In addition to the traditional ICDs present in the DSM-IV—pathological gambling, trichotillomania, kleptomania, pyromania and intermittent explosive disorder—a brief description of the new proposed ICDs—compulsive–impulsive (C–I) Internet usage disorder, C–I sexual behaviors, C–I skin picking and C–I shopping—is provided. Specifically, the article summarizes the phenomenology, epidemiology and comorbidity of the ICDs. Particular attention is paid to the relationship between ICDs and obsessive–compulsive disorder (OCD). Finally, current pharmacological options for treating ICDs are presented and discussed

Solar Aluminum Production by Vacuum Carbothermal Reduction of Alumina-Thermodynamic and Experimental Analyses

ISSN:1073-5615ISSN:1073-5623ISSN:1543-191