Bond length dependence on quantum states as shown by spectroscopy

Undergraduate students often have the misconception that molecules have fixed, unchanging bond lengths. This article discusses how linear-molecule rotational band spacings in infrared spectroscopy can be used as a qualitative, visual demonstration of the elongation of average bond lengths on vibrational excitation. The method does not depend on a detailed mathematical analysis of the spectra. In UV–vis spectroscopy, the rotational band spacings give rise to distinctive linear-molecule rotational contours, which easily show whether the average bond length has increased or decreased. The method is based on a spreadsheet simulation of the vibration–rotation or rovibronic (electronic–vibration–rotation) spectrum and is applied to hydrogen chloride IR, iodine UV–vis, and nitrogen UV–vis spectra in this article.

Supplement use is associated with health status and health-related behaviors in the 1946 British birth cohort.

Use of dietary supplements may be one of a number of health-related behaviors that cluster together. The current study investigated the underlying diet, health-related characteristics, and behaviors of users and nonusers of dietary supplements in a longitudinal study of health. Participants (n = 1776) completed a 5-d food diary including information on dietary supplement use (vitamins, minerals, and nutraceuticals) at age 53 y. Sociodemographic information and data on smoking, alcohol, and physical activity were obtained along with anthropometric measurements, blood pressure, and a blood sample (nonfasting subjects). A significantly greater percentage of women reported supplement use compared with men (45.1 vs. 25.2%). Supplement use was associated with lower BMI, lower waist circumference, higher plasma folate and plasma vitamin B-12 concentrations, nonsmoking, participation in physical activity, and nonmanual social class in women and with plasma folate concentrations and participation in physical activity in men. Nonsupplement users tended to be nonconsumers of breakfast cereals, fruit, fruit juice, yogurt, oily fish, and olive oil and had lower dietary intakes of potassium, magnesium, phosphorus, iron, and vitamin C even after adjustment for sociodemographic and behavioral factors. Overall, supplement users tended to differ from nonsupplement users on a range of health-related behaviors and health status indicators, although there were fewer significant associations in men. Similarly, dietary supplements users tended to have underlying diets that, were healthier and those taking supplements may be the least likely to need them. These results support the notion of a clustering of healthy behaviors and cardiovascular risk factors, particularly for women.

Low birth weight in South Asian babies in Britain: time to reduce the inequalities

Babies born in Britain to women of South Asian ethnic origin are lighter on average than the offspring of women of European origin. The causes have been incompletely elucidated but nutritional factors, low socioeconomic status and maternal pre-pregnancy weight have been implicated. This health inequality has received little policy prioritization in Britain. As further research clarifies reasons for this differential, appropriately targeted preventive strategies need to be implemented.

Concerning the length of time slots for efficient gang scheduling

Applying gang scheduling can alleviate the blockade problem caused by exclusively used space-sharing strategies for parallel processing. However, the original form of gang scheduling is not practical as there are several fundamental problems associated with it. Recently many researchers have developed new strategies to alleviate some of these problems. Unfortunately, one important problem has not been so far seriously addressed, that is, how to set the length of time slot to obtain a good performance of gang scheduling. With gang scheduling time is divided into time slots of equal length, the number of time slots introduced in the system forms a scheduling round and each new job is first allocated to a particular time slot and then starts to run in the following scheduling round. Ideally, the length of time slot should be set long to avoid frequent context switches and so to reduce the scheduling overhead. The number of time slots in a scheduling round should also be limited to avoid a large number of jobs competing for limited resources (CPU time and memory). Long time slots and the limited number of time slots in each scheduling round may cause jobs to wait for a long time before it can be executed after arrival, which can significantly affect the performance of jobs, especially short jobs which are normally expected to finish quickly. However, the performance of a short job can also suffer if the length of time slot is not long enough to let the short job complete in a single time slot. In this paper we present a strategy to deal with this important issue for efficient gang scheduling.

Dietary composition of pregnant women is related to size of the baby at birth

The fetal origins theory of adult disease suggests that term infants who are small for their gestational age have an increased susceptibility to chronic disease in adulthood as a consequence of physiologic adaptations to undernutrition during fetal life. Consistent evidence for an influence of women's dietary composition during pregnancy on growth of their babies is lacking, despite robust effects in animal experiments. We undertook a prospective observational study of 557 women aged 18-41 y, living in Adelaide, South Australia. Diet was assessed in early and late pregnancy using an FFQ. In early pregnancy, medians for energy intake, the proportion of energy derived from protein and from carbohydrate were 9.0 MJ, 17 and 48%, respectively. In late pregnancy the corresponding medians were 9.2 MJ, 16 and 49%. In early pregnancy, the percentage of energy derived from protein was positively associated with birth weight (P = 0.02) and placental weight (P = 0.07), independently of energy intake and weight gain during pregnancy, and after adjustment for potential confounders, including maternal age, parity, and smoking. Effects were stronger among women (n = 429) who had reliable data, based on prespecified criteria including the plausibility of dietary data when referenced against estimated energy expenditure. In addition, for this subgroup, the percentage of energy from carbohydrate in early and late pregnancy was negatively associated with ponderal index of the baby, and a specific effect of protein from dairy sources was identified. These data support the proposition that maternal dietary composition has an effect on fetal growth. Maternal diet in Western societies may therefore be important for the long-term health of the child.

Choosing response scale labels and length: guidance for researchers and clients

There has been much debate over the optimal format for scales, particularly in regard to two key issues - the labelling of points and the overall length of response scales. This paper reviews the evidence regarding the advantages of different scale types and lengths, and provides guidance as to what scale types suit different research objectives. Using a direct comparison of 400 responses on 5-point and 11 -point scales to the same question, by the same people, we examine some of the important differences previously found and then illustrate the impact they have on data quality and useability. Our conclusion, based on past research and our own analysis, is that longer, balanced and unlabelled scales offer the maximum flexibility and reliability in the majority of cases.

Emotional intelligence and teacher self efficacy : the contribution of teacher status and length of experience

Practicing teachers and principals in selected Government schools in Victoria provided data on their levels of emotional intelligence and teacher efficacy beliefs. The data supported the theoretical expectation of a linkage between emotional intelligence and teacher self efficacy. Regression analyses showed that neither gender nor age moderated this relationship. However length of teaching experience and current status add significant direct effects on predicting teacher self efficacy but did not moderate the relationship between emotional intelligence and teacher self efficacy. These findings are significant as this now demonstrates a relationship between levels of emotional intelligence in teachers, their self efficacy beliefs and teacher effectiveness.

Angiotensin converting enzyme inhibition from birth reduces body weight and body fat in Sprague-Dawley rats

In vitro studies have demonstrated that angiotensin II (ANG II) induces adipocyte hyperplasia and hypertrophy. The aim of the present study was to determine the effect of angiotensin-converting enzyme inhibition on body weight, adiposity and blood pressure in Sprague–Dawley rats. From birth half of the animals (n = 15) were given water to drink, while the remainder were administered perindopril in their drinking water (2 mg/kg/day). Food intake, water intake and body weight were measured weekly. Blood pressure was measured by tail cuff plethysmography at 11-weeks. Body fat content and distribution were assessed using dual energy X-ray absorptiometry and Magnetic Resonance Imaging at 12 weeks. Animals administered with perindopril had a body fat proportion that was half that of controls. This was consistent with, but disproportionately greater than the observed differences in food intake and body weight. Perindopril treatment completely removed hypertension. We conclude that the chronic inhibition of ANG II synthesis from birth specifically reduces the development of adiposity in the rat.

Why wrongful birth actions are right

A wrongful birth action is a claim in negligence brought by parents of a child against a doctor who has "wrongfully" caused their child to be born. These claims can be divided into two categories: those where a doctor performs a failed sterilisation procedure that leads to a healthy child being born; and those where a doctor fails to provide sufficient information to allow parents to choose to abort a handicapped child. The recent decision of the High Court of Australia in Cattanach v Melchior (2003) 77 ALJR 1312 falls into the former category. The decision to allow the parents to receive damages for the costs of raising and maintaining their child has generated much public debate. Despite the endorsement of this "wrongful birth" action, there are indications that the legislature will overturn the decision. This article examines whether there is a sound doctrinal basis for recognising wrongful birth actions.