Impact of distressed and aggressive behavior.

Two studies examined the hypothesis that distressed behavior induces negative emotions in others but also prompts solicitousness and deters aggression. In Study 1, 48 marital dyads rated various behaviors in terms of their feelings and reactions toward a spouse engaging in each behavior. Distressed behavior prompted both negative and solicitous emotions, but deterred hostile reactions. Aggressive behavior prompted negative feelings and hostile and argumentative reactions. In Study 2, 41 couples rated videotaped examples of a woman engaging in distressed, aggressive, or neutral behavior, with variations in verbal content and nonverbal affect. Examples of distressed behavior prompted more negative feelings and more solicitous feelings than neutral behavior. Aggressive examples prompted more negative feelings and hostile reactions. The studies indicate the importance of distinguishing between distressed and aggressive behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Toward a definition of self-care children: A commentary on Steinberg (1986).

This comment responds to an article by Steinberg (1986) in which he stressed the desirability of investigating a wide variety of after-school experiences when examining consequences for latchkey (self-care) children. In presenting his results, he inadvertently confounded latchkey children with adolescents who spent time at a friend's house or who "hang out" with friends without adult supervision. Steinberg reported that these adolescents showed greater susceptibility to peer pressure to engage in antisocial activities. We point out that these adolescents do not fit the usual conceptualization of latchkey children and that Steinberg's study may lend support to practitioners and policy makers who assume negative latchkey consequences in the absence of research evidence. To avoid future confusion we indicate the need for a definition of latchkey children and offer a tentative definition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Glycerol,glucose and 2-acetoacetoxyethyl methacrylate: Effect on methyl linolenate oxidation and yellowing

The effect of glycerol, glucose and acetoacetoxyethyl methacrylate (AAEM) on autoxidation and yellowing of methyl linolenate has been investigated by nuclear magnetic resonance (NMR) and ultraviolet (UV)-Visible spectroscopies. The extent of autoxidation was determined by measuring the NMR integration of vinylic protons with respect to methoxy protons, an internal standard, as a function of time. The extent of yellowing was determined by measuring the difference in absorbance at 400 nm and 450 nm as a function of time. Glycerol and AAEM showed inhibition of autoxidation, but the most significant effect was observed with AAEM. Glucose enhanced the autoxidation of methyl linolenate. Inhibition of yellowing was observed with all these compounds, especially with glycerol and AAEM.     

Why does the brain prefer opium to broccoli?

Hemangiomas present at, or soon after birth, proliferate and eventually involute. In spite of this, children may suffer severe psychosocial trauma during the formative years of their lives, and, in a proportion of cases, a cosmetically unacceptable result is left at the end of involution. Since flashlamp pumped dye lasers have been shown to selectively destroy ectatic dermal vascular tissue through intact epidermis, 6 patients with very early superficial cutaneous hemangiomas were treated. All treated areas resolved completely and treatment was completed by 12 months. No complications were encountered apart from mild, temporary post-inflammatory hyperpigmentation which was seen in one patient. This, however, resolved completely within 3 months of treatment. Flashlamp pumped dye lasers are thus able to effect complete resolution of very superficial proliferating cutaneous hemangiomas in neonates and infants without the risk of scarring.     

Getting the focus right: production constraints for six major food crops in Asian and African farming systems

To determine the most important production constraints and associated yield losses for six major food crops in 13 farming systems with high poverty in Sub-Saharan Africa, South Asia and East Asia, surveys were conducted with 672 experts representing a diversity of backgrounds and experience. Respondents reported large gaps between highest achieved crop yield on smallholder farms and average yield on farm. Yield gaps were smallest for rice (about 60% of current average smallholder farm grain yields), mid size for wheat and cassava, and larger (sometimes double current farm yields) for sorghum, cowpea and chickpea. Gaps were also smaller in the high input and yield farming systems of East Asia and largest in the marginal, drier systems, particularly in Sub-Saharan Africa. Four categories of production constraint (abiotic, biotic, management and socio-economic) were considered important contributors to yield gaps. A diversity of specific constraints was reported for the crops in the different systems. The most severe and widespread specific constraints for wheat involved the deficiency, high cost and poor management of N fertilizer, and problems associated with drought stress at grain filling, mid season drought and irrigation management. Those for rice included N fertilizer problems, soil fertility depletion, various leaf, stem and head pests and diseases, weed competition and inadequate water management. Striga and weed competition, soil resource degradation, poor soil fertility management, and drought were the most severe specific constraints for sorghum. Insect pests of pod, leaf, stem and flower and the high cost of their control dominated the constraint set for cowpea. Helicoverpa pod borer, Botrytis grey mould and control costs were the most severe for chickpea. Unsuitable varieties/poor seed, soil infertility and fertilizer constraints were also widespread with the legumes. Marketing problems and lack of finance were concerns for cassava along with weed competition, African cassava mosaic virus and poor varieties/planting materials. The findings can help to inform priority setting for international agricultural research and development activities on important food crops in major farming systems occupying areas of high poverty.     

Adolescent smoking trajectories and nicotine dependence.

The present study correlates empirically constructed prospective adolescent smoking trajectories with indicators of nicotine dependence assessed in adolescence and in adulthood. Excluding individuals who reported no smoking during repeat assessment (nonadopters), we identified five smoking trajectory groups: experimenters (n=116, 48.5%), late increasers (n=39, 16.3%), early increasers (n=37, 15.5%), quitters (n=22, 9.2%), and persistent smokers (n=25, 10.5%). Higher frequency of nicotine dependence symptoms in adolescence occurred in the quitters and persistent smokers groups, who smoked at higher levels relative to the experimenters, late increasers, and early increasers groups, who reported a similar frequency of nicotine dependence symptoms and smoked at low levels. Lifetime nicotine dependence was assessed in adulthood in lifetime daily smokers using the Fagerstr?m Test for Nicotine Dependence (FTND) and the Nicotine Dependence Scale (NDS). Lifetime FTND levels were similar across trajectory groups. Relative to experimenters, all remaining smoking trajectory groups had higher NDS levels that were similar to one another. These results suggest that higher levels of adolescent nicotine dependence were associated with heavier smoking trajectory groups, and that regardless of trajectory group membership, smoking more than a few cigarettes per week throughout adolescence resulted in similar levels of lifetime nicotine dependence as measured by the FTND and NDS.     

Investigating the effects of excipients on the powder flow characteristics of theophylline anhydrous powder formulations

Pharmaceutical excipients may have a great effect on properties affecting tablet production. To determine if formulations containing theophylline anhydrous would have properties allowing them to be easily tableted, functional parameters affecting powder flow were evaluated. The Carr Flowability Indices were used for this evaluation. Formulations to be studied include theophylline anhydrous as the active ingredient, hydrous lactose and dicalcium phosphate dihydrate as diluents, polyvinylpyrrolidone as a binder, and fumed silica as a flow promoter. The effect of each component on powder flow is discussed.     

The development of a truck scale management system for the sugar industry in Trinidad and Tobago

Summary

The paper reviews a project on the development of a Truck Scale Management System (TSMS) for Caroni (1975) Limited, a State Enterprise which is seeking to improve efficiency and consequently reduce costs in its operation.

The paper also provides a background on factors which significantly affect process automation. The most important of these relate to the lack of awareness by top management of the varied use and benefits of microelectronics and information technology, shortage of relevant human resources and insufficient investment incentives.

Automation of the weighbridge was given high priority by Caroni's decision makers because of allegations of falsification of weights, the inability to get timely and adequate information for decision making and the labour intensiveness of the manual system. A project was undertaken to design, procure, install, commission and operate an unmanned TSMS at both factories using local personnel to execute the project. Caroni formed a multi‐disciplinary team from in‐house, a publicly funded research institution and a local supplier. The team designed the system (providing a number of options), assessed the technology, acquired a number of microprocessor‐based modules including load cell technology, bar code technology, magnetic card readers and modems, and implemented the system as two separate pilots. Software was developed by Caroni to integrate all these systems. The team was successful in demonstrating the fully automated system under crop conditions but it has not been implemented in completeness as the decision makers required additional trials.

Cane operators were trained in keyboard data entry and the users, including contractors, were taken through the procedures before the system was put on stream. Caroni has organized training programmes involving this new technology for its engineers and technicians, aimed mainly at integrating new technologies with existing skills. The system could be commercialized. One cane producing country has shown interest in acquiring the technology. It is possible to package the system and target it for applications in activities such as grain and cement weight controls.

Some of the spin‐offs from the experience gained from the project include the automation of Caroni's juice scales at both factories, proposed automation of the juice clarification, evaporation and sugar boiling, and automation of the laboratories.

The system has gained acceptance by all those who interfaced with it. Caroni has had no adverse reaction to the TSMS from the workers but for future automation projects would have to develop strategies of redeployment and retraining to avoid the backlash of resentment and opposition which could hinder progress.     

The effect of inner products for discrete vector fields on the accuracy of mimetic finite difference methods

The support operators method of discretizing partial differential equations produces discrete analogs of continuum initial boundary value problems that exactly satisfy discrete conservation laws analogous to those satisfied by the continuum system. Thus, the stability of the method is assured, but currently there is no theory that predicts the accuracy of the method on nonuniform grids. In this paper, we numerically investigate how the accuracy, particularly the accuracy of the fluxes, depends on the definition of the inner product for discrete vector fields. We introduce two different discrete inner products, the standard inner product that we have used previously and a new more accurate inner product. The definitions of these inner products are based on interpolation of the fluxes of vector fields. The derivation of the new inner product is closely related to the use of the Piola transform in mixed finite elements. Computing the formulas for the new accurate inner product requires a nontrivial use of computer algebra. From the results of our numerical experiments, we can conclude that using more accurate inner product produces a method with the same order of convergence as the standard inner product, but the constant in error estimate is about three times less. However, the method based on the standard inner product is easier to compute with and less sensitive to grid irregularities, so we recommend its use for rough grids.     

Computer arithmetic for probability distribution variables

The uncertainty in the variables and functions in computer simulations can be quantified by probability distributions and the correlations between the variables. We augment the standard computer arithmetic operations and the interval arithmetic approach to include probability distribution variable (PDV) as a basic data type. Probability distribution variable is a random variable that is usually characterized by generalized probabilistic discretization. The correlations or dependencies between PDVs that arise in a computation are automatically calculated and tracked. These correlations are used by the computer arithmetic rules to achieve the convergent approximation of the probability distribution function of a PDV and to guarantee that the derived bounds include the true solution. In many calculations, the calculated uncertainty bounds for PDVs are much tighter than they would have been had the dependencies been ignored. We describe the new PDV Arithmetic and verify the effectiveness of the approach to account for the creation and propagation of uncertainties in a computer program due to uncertainties in the initial data.