Sex- and season-dependent behaviour in a flightless insect, the Auckland tree weta (Hemideina thoracica)

In a polygynous mating system, males frequently compete by locating and defending sites with resources essential to female survival and reproduction. We investigated seasonal changes in site occupancy in a sexually dimorphic, harem-forming insect, the Auckland tree weta (Hemideina thoracica). First we established artificial cavities as diurnal refuge cavities and potential harem guarding sites. We then examined cavity occupancy changes, and, based on our knowledge of prior occupants, determined sex-specific patterns of arrival, departure, and aggregation at a population level throughout the year. Both season and the sex of prior occupants influenced weta occupancy patterns. Most observations were of single females. However, both males and females moved into cavities previously occupied by a weta of the opposite sex more often than expected by chance alone. Females avoided cavities where other females were present, except during summer when most harems formed. In early summer, male and female tree weta previously living apart began co-habiting. Generally there was little relationship between the number and sex of the weta inside cavities and female departure rates from cavities. Males who were sharing with other males departed cavities more frequently than single males, as might be expected in a polygynous species with male-male combat. Males were less likely to depart if they were sharing a cavity with a harem of more than two females during the summer-autumn period. Analysis of departure rates from artificial cavities indicates males are more mobile than females only in winter and spring. Based on our arrival and departure data, and high occupancy of artificial cavities, we suggest that female weta at this site are mobile and may search for mates during the summer. The data are consistent with a polygynandrous mating system as inferred for other tree weta species (Hemideina spp.)

Policing the Global Economy: The Threat to Private Enterprise

International organizations are becoming increasingly involved in the regulation of private enterprise. Advocates of this type of regulation seem to have overlooked the shortcomings of existing regulation of business. Ultimately, it is the consumer who bears the burden that government imposes on business.https://openscholarship.wustl.edu/mlw_papers/1060/thumbnail.jp

Oxygen Consumption of Adrenalectomized and Renal Damaged Frogs

Author Institution: Department of Physiology, College of Medicine, The Ohio State University, Columbus 1

Hinge Moments of Sealed-Internal-Balance Arrangements for Control Surfaces I : Theoretical Investigation

The results of a theoretical analysis of the hinge-moment characteristics of various sealed-internal-balance arrangements for control surfaces are presented. The analysis considered overhands sealed to various types of wing structure by flexible seals spanning gaps of various widths or sealed to the wing structure by a flexible system of linked plates. Leakage was not considered; the seal was assumed to extend the full spanwise length of the control surface. The effect of the developed width of the flexible seal and of the geometry of the structure to which the seal was anchored was investigated, as well as the effect of the gap width that is sealed. The results of the investigation indicated that the most nearly linear control-surface hinge-moment characteristics can probably be obtained from a flexible seal over a narrow gap (about 0.1 of the overhang chord), which is so installed that the motion of the seal is restricted to a region behind the point of attachment of the seal to the wing structure. Control-surface hinge moments that tend to be high at large deflections and low or overbalanced at small deflections will result if a very narrow seal is used

Photocontrol of Upper and Lower Rim Complexation of Neutral and Cationic Species by p-tert-butylcalix[4]arene Tetraethyl Ester

A number of sodium salt complexes of p-tert-butylcalix[4]arene tetraethyl ester, 1, were isolated both with and without upper-rim encapsulated solvent. Selective decomplexation of lower rim bound sodium cations and upper rim encapsulated solvent molecules could be successfully achieved using low pressure light sources. Oxidation of the counter anion at the lower rim of p-tert-butylcalix[4]arene tetraethyl ester triggered both the upper and lower rim decomplexation process. The extent of decomplexation at both rims is controlled both by the nature of the counter-anionic species at the lower rim and by the fate of the photoproducts generated. The calixarene host molecule, 1, remains intact during the decomplexation process

Novel Calixarene-Schiff Bases that Bind Silver(I) Ion

Two novel calix[4]arene-Schiff base receptors have been synthesized. One of the new compounds has two pendant aldimines, while the second has been prepared by two-point attachment of a calixarene-dialdehyde onto a calixarene-diamine to form a “calix-tube”. Preliminary binding studies with AgClO4 show large complexation-induced shifts in 1H NMR positions

Developing a School Functioning Index for Middle Schools

Despite widespread recognition of schools\u27 role in the healthy development of youth, surprisingly little research has examined the relationships between schools\u27 overall functioning and the health‐related behavior of students. School functioning could become an important predictor of students\u27 health‐related behavior and may be amenable to intervention. This paper describes the development and testing of the School Functioning Index (SFI) as a first step in investigating this question. The index was developed for use with middle schools and conceived as a predictor of students\u27 violent behavior, with the potential for extending research applications to additional health and social behaviors. Using social cognitive theory, social ecological theory, and social disorganization theory as guides, three domains were identified to operationalize school functioning and identify candidate SFI items: 1) resources available to the school and students; 2) stability of the school population; and 3) the schools\u27 performance as a socializing agent for students. Data for candidate SFI items were collected from public archives and directly from 16 middle schools participating in a school‐based dietary intervention study. Data collection from schools, particularly concerning student aggressive behavior and disciplinary actions, presented challenges. The final SFI comprised nine items and demonstrated good internal consistency and variability. The SFI was modestly correlated in expected directions with violence and other health behaviors. This work supports the feasibility of combining multiple school‐level indicators to create a measure of overall school functioning. Further investigation of validity and more acceptable data collection methods are warranted

Perceptions of the Family Mealtime Environment and Adolescent Mealtime Behavior: Do Adults and Adolescents Agree?

The family mealtime environment has great potential to affect the eating behaviors of youth in the family. It is difficult to determine the important elements of a healthy mealtime environment because a valid assessment of the family environment is so difficult to obtain. The objective of this study is to examine the level of agreement between adult and adolescent perceptions of the family mealtime environment and adolescent mealtime behavior. A telephone survey was used to query adult and adolescent family members about how they perceive the family mealtime environment and the adolescent\u27s mealtime behavior. A convenience sample of 282 adult/adolescent pairs from four schools in the Minneapolis/St. Paul area completed the telephone surveys. Frequencies of responses and the associations between the adult and adolescent responses are presented. Pearson correlations and regression were used to examine the level of association between adult and adolescent responses. Mixed-model regression was used for the continuous variables, and mixed-model logistic regression was used for the dichotomous variables. This study showed very little concordance between adolescent and adult responses. Only one question regarding arguments about eating during mealtime showed concordance. Adults and adolescents living in the same household seem to have different perceptions of the family mealtime environment and adolescent eating patterns. Researchers need to be aware of and concerned with the validity of the use of self-report for descriptions of family mealtime. They also need to be aware of the difference in adult and adolescent perceptions and consider these differences when designing messages for the family

Are Differences in Exposure to a Multicomponent School-Based Intervention Associated With Varying Dietary Outcomes in Adolescents?

Multicomponent interventions are recommended for health behavior change among adolescents. However, it is difficult to disentangle the effects of multiple intervention components. This article reports outcomes associated with varying levels of exposure to a school-based nutrition intervention, Teens Eating for Energy and Nutrition at School (TEENS). Four incremental exposureswere possible: (1) control group, (2) school environment interventions only, (3) classroom plus environment interventions, and (4) peer leaders plus classroom plus environment interventions. Patterns suggesting dose response were observed, with peer leaders reporting the largest increases in fruit, vegetable, and lower fat food consumption. Students exposed to classroom plus environment interventions also improved, whereas students exposed only to school environment interventions showed trends toward choosing lower fat foods and declining fruit intake and no change in vegetable intake. Control students’ choices remained stable. Future studies may investigate mechanisms for peer leaders’ changes, maximizing curriculum effectiveness, and improving environmental interventions

Predicting Adolescents’ Intake of Fruits and Vegetables

Objective To explore potential predictors of adolescent fruit and vegetable intake by expanding on current theory and drawing from other adolescent research. Design This research reports on the baseline and interim data from a school-based intervention study. Data were collected through surveys administered to students at the beginning and end of their 7th-grade year. Setting The students attended 16 public schools in Minnesota. Participants Data were collected on 3878 students; approximately half were female and 67% were white. All students in the 7th-grade cohort were invited to participate in the surveys and over 94% completed both surveys. Variables Measured Our dependent variable, fruit and vegetable intake, was assessed by a validated fruit and vegetable food frequency scale. Predictive factors assessed included parenting style, spirituality/religiosity, depressive symptoms, and other commonly assessed predictors. Analysis Generalized linear mixed model regression. Omnibus test of association using P \u3c .05 is reported. Results Subjective norms, barriers, knowledge, usual food choice, parenting style, spirituality /religiosity, and depressive symptoms were statistically significant predictors of intake. The model explained about 31% of the variance in fruit and vegetable consumption. Conclusions and Implications To better understand adolescents\u27 fruit and vegetable intake, we must explore novel predictors. Our results need to be replicated, and more exploratory research in this field is needed