Body-centric antenna positioning effects for off-body UWB communications in a contemporary learning environment

The propagation of UWB signals for body-centric communications within a modern classroom/conference room environment was investigated. Presented results demonstrate that the body-antenna mounting position has a marked impact on the received power levels and positioning the antenna on the chest as opposed to the shoulder or wrist creates more extreme values in receive power, mean excess delay and rms delay spread. Additionally, the best fit models for each scenario are presented and highlight the difference between the chest and other compared antenna locations. The work concluded that the chest is a poor choice of mounting position for the antenna due to significant body shadowing effects, with the wrist or shoulder considered better options for UWB systems.

RSSI-based environment identification for 2.45 GHz body area networks

A unique property of body area networks (BANs) is the mobility of the network as the user moves freely around. This mobility represents a significant challenge for BANs, since, in order to operate efficiently, they need to be able to adapt to the changing propagation environment. A method is presented that allows BAN nodes to classify the current operating environment in terms of multipath conditions, based on received signal strength indicator values during normal packet transmissions. A controlled set of measurements was carried out to study the effect different environments inflict on on-body link signal strength in a 2.45 GHz BAN. The analysis shows that, by using two statistical parameters, gathered over a period of one second, BAN nodes can successfully classify the operating environment for over 90% of the time.

The neighborhood social environment and body mass index among youth : a mediation analysis

Background

This study aimed to examine associations between aspects of the neighborhood social environment and body mass index (BMI) in youth both cross-sectionally and prospectively; and whether this association was mediated by physical activity, screen-time and sedentary time.
Methods

Data were collected in 2004 and 2006 in high and low socio-economic areas of Melbourne, Australia. In 2004, 185 children aged 8-9 years (47% boys) and 359 children aged 13-15 years (45% boys) participated. Parents reported their perceptions of aspects of the social environment (i.e. social networks and social trust/cohesion), and physical activity (i.e. time spent outdoors by their children; and their younger children's walking and cycling trips) and screen-time (i.e. TV viewing, computer use). The older children self-reported their walking and cycling trips and their screen-time. All children wore an accelerometer to objectively assess outside-school hours moderate- to-vigorous physical activity and sedentary time. BMI was calculated from height and weight measured in 2004 and 2006. Multilevel linear regression analyses were conducted to examine associations between the social environment and BMI. Mediation analyses using the products of coefficient method were conducted to determine whether associations between the social environment and BMI were mediated by the time spent in a range of physical activity and sedentary behaviors.
Results

Cross-sectional and prospective regression analyses showed that a more positive social network and higher social trust/cohesion was related to lower BMI among children. There was no evidence that time spent in physical activity or sedentary behaviors mediated this relation, despite significant associations between social networks and screen-time and between screen-time and BMI.
Conclusions

The findings suggest that the neighborhood social environment may be important for preventing overweight and obesity in children. Further research investigating the mechanisms through which the neighborhood social environment exerts its effect on BMI is needed.

Effect of changes to the school food environment on eating behaviours and/or body weight in children: a systematic review

Previous school obesity-prevention reviews have included multi-component interventions. Here, we aimed to review the evidence for the effect of isolated food environment interventions on both eating behaviours (including food purchasing) and/or body weight. Five electronic databases were searched (last updated 30 November 2013). Of the 1,002 unique papers identified, 55 reported on school food environment changes, based on a review of titles and abstracts. Thirty-seven further papers were excluded, for not meeting the inclusion criteria. The final selection consisted of 18 papers (14 United States, 4 United Kingdom). Two studies had a body mass index (BMI) outcome, 14 assessed purchasing or eating behaviours and two studies assessed both weight and behaviour. Seventeen of 18 papers reported a positive outcome on either BMI (or change in BMI) or the healthfulness of food sold or consumed. Two studies were rated as strong quality and 11 as weak. Only three studies included a control group. A school environment supportive of healthy eating is essential to combat heavy marketing of unhealthy food. Modification of the school food environment (including high-level policy changes at state or national level) can have a positive impact on eating behaviours. A need exists, however, for further high-quality studies.

Effects of sex and age on genotype x environment interaction for beef cattle body weight studied using reaction norm models

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Sensible and latent heat loss from the body surface of Holstein cows in a tropical environment

The general principles of the mechanisms of heat transfer are well known, but knowledge of the transition between evaporative and non-evaporative heat loss by Holstein cows in field conditions must be improved, especially for low-latitude environments. With this aim 15 Holstein cows managed in open pasture were observed in a tropical region. The latent heat loss from the body surface of the animals was measured by means of a ventilated capsule, while convective heat transfer was estimated by the theory of convection from a horizontal cylinder and by the long-wave radiation exchange based on the Stefan-Boltzmann law. When the air temperature was between 10 and 36 degrees C the sensible heat transfer varied from 160 to -30 W m(-2), while the latent heat loss by cutaneous evaporation increased from 30 to 350 W m(-2). Heat loss by cutaneous evaporation accounted for 20-30% of the total heat loss when air temperatures ranged from 10 to 20 degrees C. At air temperatures > 30 degrees C cutaneous evaporation becomes the main avenue of heat loss, accounting for approximately 85% of the total heat loss, while the rest is lost by respiratory evaporation.

Circadian and seasonal variation of the body temperature of sheep in a tropical environment.

Nychthemeral and annual rhythms of the rectal temperature were determined for Corriedale sheep in a tropical climate. The minimum rectal temperature averaged 39.55 degrees C at 0500 hours in summer, and 38.87 degrees C at 0600 hours in winter. The maximum was 40.03 degrees C in summer (1700 hours) and 39.33 degrees C in winter (1830 hours). Annual cycle of the rectal temperature showed a minimum in July and maximum in December.

Towards an Active Design. An Approach on the Body Interaction with the Built Environment.

El impacto de la tecnología en el ambiente construido y en las actividades en él desarrolladas, es una de las causas de la progresiva sedentarización de la especie humana. Desde un enfoque que analiza la interacción del cuerpo con la arquitectura, a través de distintas referencias en escalas diversas, esta investigación intenta establecer la relación entre la evolución del ambiente pasivo y la sedentarización, proponiendo frente a un espacio mecanizado y digitalizado que disminuye la actividad física humana, la búsqueda de nuevos tipos de espacios arquitectónicos que promuevan el movimiento repercutiendo en el bienestar y la salud. Esta tesis estudia por tanto el impacto de la tecnología en el espacio, intentando aproximarse a estrategias que disminuyan el efecto pasivo y estimulen la actividad motora. Estas propuestas abarcan tanto la ciudad, como la edificación y el propio espacio doméstico afectando a los sistemas de circulación, a la configuración espacial y sobre todo a la incorporación de ”espacios activos”, en donde se contempla la posibilidad de un uso alternativo de la tecnología como un elemento positivo.

Perceptions of family environment, body image and self-esteem of eating disordered and non-eating disordered women

This study explored the perceptions of family environment, body image and self esteem of women who suffer from anorexia nervosa, bulimia nervosa, and depression. Using a nonequivalent control group design, one hundred and fifty women with anorexia nervosa (n = 50), bulimia nervosa (n = 50), and depression (n = 50) were given the Family Environment Scale (FES) and the Eating Disorders Inventory-2 (EDI-2). The objectives of this study were to: (1) study how women with anorexia nervosa and bulimia nervosa perceive their family environment as measured by the FES; (2) compare and contrast perceptions of family environment of women with anorexia nervosa and bulimia nervosa with the control group; (3) compare and contrast perceived levels of self esteem and body image as measured by the EDI-2 of women with anorexia nervosa and bulimia nervosa with the control group; and (4) examine the perceived family environments of eating disordered and non-eating disordered women with regard to body image and self esteem. Results suggested, women who suffered from anorexia nervosa or bulimia nervosa scored significantly lower (p $<$.021) on the Expressiveness, Intellectual-Cultural Orientation, and Active-Recreational subscales of the FES. The results also indicated that women who suffered from bulimia nervosa scored significantly higher (p $<$.015) than women who suffered from anorexia nervosa on the Conflict and Independence subscales of the FES. The results of studying these three populations reflected that women who suffered from anorexia nervosa scored significantly different (p $<$.000) than women who suffered from bulimia nervosa on many of the subscales of the EDI-2. The findings of the study confirmed that women who suffered from anorexia nervosa or bulimia nervosa scored significantly different (p $<$.000) on the subscales of the EDI-2 compared to women who suffered from depression. It was also confirmed that a relationship does exist between perceptions of body image and self esteem and perceptions of family environment amongst women with anorexia nervosa and bulimia nervosa as compared to depressed women. The findings of the study indicated that women who suffered from anorexia nervosa tended to: be less expressive and independent; handle conflict less openly; have a greater drive for thinness; have greater body dissatisfaction; be more perfectionistic; and struggle more intensely with fears around maturity and social insecurity than did women who suffered from bulimia nervosa or depression. In addition, the findings of the study also suggested that women who suffered from bulimia nervosa tended to: be raised in homes where openly expressed anger is permitted amongst family members; have a lesser drive for thinness; have less body dissatisfaction; be less perfectionistic; and not struggle as intensely with fears around maturity and social insecurity as do women who suffered from anorexia nervosa, but more than women who suffer from depression. Treatment implications that may assist community college professors and counselors in meeting the special needs of this special group of women were also discussed. (Abstract shortened by UMI.) ^

The guide to the project management body of knowledge (PMBOK Guide) : applicability and contribution to project success in Australia

The PMBOK Guide is one of the most influential publications concerning the knowledge of the project manangement. Moreover, the pervasion of this guide seems to be set to increase as the basis of accreditation - in conjunction with the increasing global trend toward obtaining project management professional status. However, despite the influence and strengthening profile of this guide, reports continue to be published that detail numerous project failures in a wide range of different industries. The PMBOK Guide comprises mainly declarative (know-what) and procedural (know-how) information. In this sense, the guide is largely normative and provides a very good example of the limitations of this approach as highlighted by proponents of a move to the genuine application of positibe theory in project management.----- The aim of this paper is to determine the applicability of the guide in Australia and to determine the extent to which project success can be attributed to the guide. Project Managers from a variety of organisations were surveyed. This postal survey yielded 48 replies. Descriptive statistics was used to assess the incidence and effectivieness of all the processes in the guide. The results indicate that there were no processes that could be considered as peripheral or as a candidate for elimination from the guide. More specifically, all the processes were identified as either a key routine process or a key selective process and positively related to the level of project success. However, the results also indicated that other major factors pertaining to causal knowledge (know-why) are, at least, equally important determinants of project success. It is concluded that declarative, procedural and causal knowledge are all valuable, and given the preponderance of the first two types of knowledge, there seems to be an urgent need to now ensure an equal quest for causal knowledge. In terms of developing causal knowledge, a good starting point would appear to be both positive theory from production and economics.

Attention and memory bias for body image and health related information using an Emotional Stroop task in a non-clinical sample

It has been proposed that body image disturbance is a form of cognitive bias wherein schemas for self-relevant information guide the selective processing of appearancerelated information in the environment. This threatening information receives disproportionately more attention and memory, as measured by an Emotional Stroop and incidental recall task. The aim of this thesis was to expand the literature on cognitive processing biases in non-clinical males and females by incorporating a number of significant methodological refinements. To achieve this aim, three phases of research were conducted. The initial two phases of research provided preliminary data to inform the development of the main study. Phase One was a qualitative exploration of body image concerns amongst males and females recruited through the general community and from a university. Seventeen participants (eight male; nine female) provided information on their body image and what factors they saw as positively and negatively impacting on their self evaluations. The importance of self esteem, mood, health and fitness, and recognition of the social ideal were identified as key themes. These themes were incorporated as psycho-social measures and Stroop word stimuli in subsequent phases of the research. Phase Two involved the selection and testing of stimuli to be used in the Emotional Stroop task. Six experimental categories of words were developed that reflected a broad range of health and body image concerns for males and females. These categories were high and low calorie food words, positive and negative appearance words, negative emotion words, and physical activity words. Phase Three addressed the central aim of the project by examining cognitive biases for body image information in empirically defined sub-groups. A National sample of males (N = 55) and females (N = 144), recruited from the general community and universities, completed an Emotional Stroop task, incidental memory test, and a collection of psycho-social questionnaires. Sub-groups of body image disturbance were sought using a cluster analysis, which identified three sub-groups in males (Normal, Dissatisfied, and Athletic) and four sub-groups in females (Normal, Health Conscious, Dissatisfied, and Symptomatic). No differences were noted between the groups in selective attention, although time taken to colour name the words was associated with some of the psycho-social variables. Memory biases found across the whole sample for negative emotion, low calorie food, and negative appearance words were interpreted as reflecting the current focus on health and stigma against being unattractive. Collectively these results have expanded our understanding of processing biases in the general community by demonstrating that the processing biases are found within non-clinical samples and that not all processing biases are associated with negative functionality

The effect of insertion time on the axial pullout strength of anterior vertebral body screws

Top screw pullout occurs when the screw is under too much axial force to remain secure in the vertebral body. In vitro biomechanical pullout tests are commonly done to find the maximum fixation strength of anterior vertebral body screws. Typically, pullout tests are done instantaneously where the screw is inserted and then pulled out immediately after insertion. However, bone is a viscoelastic material so it shows a time dependent stress and strain response. Because of this property, it was hypothesised that creep occurs in the vertebral trabecular bone due to the stress caused by the screw. The objective of this study was therefore to determine whether the axial pullout strength of anterior vertebral body screws used for scoliosis correction surgery changes with time after insertion. This study found that there is a possible relationship between pullout strength and time; however more testing is required as the sample numbers were quite small. The design of the screw is made with the knowledge of the strength it must obtain. This is important to prevent such occurrences as top screw pullout. If the pullout strength is indeed decreased due to creep, the design of the screw may need to be changed to withstand greater forces.

Body-shadowing effects in indoor MIMO-OFDM channel capacity

We investigate Multiple-Input and Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) systems behavior in indoor populated environments that have line-of-site (LoS) between transmitter and receiver arrays. The in-house built MIMO-OFDM packet transmission demonstrator, equipped with four transmitters and four receivers, has been utilized to perform channel measurements at 5.2 GHz. Measurements have been performed using 0 to 3 pedestrians with different antenna arrays (2 £ 2, 3 £ 3 and 4 £ 4). The maximum average capacity for the 2x2 deterministic Fixed SNR scenario is 8.5 dB compared to the 4x4 deterministic scenario that has a maximum average capacity of 16.2 dB, thus an increment of 8 dB in average capacity has been measured when the array size increases from 2x2 to 4x4. In addition a regular variation has been observed for Random scenarios compared to the deterministic scenarios. An incremental trend in average channel capacity for both deterministic and random pedestrian movements has been observed with increasing number of pedestrian and antennas. In deterministic scenarios, the variations in average channel capacity are more noticeable than for the random scenarios due to a more prolonged and controlled body-shadowing effect. Moreover due to the frequent Los blocking and fixed transmission power a slight decrement have been observed in the spread between the maximum and minimum capacity with random fixed Tx power scenario.