Optimal H∞ insulin injection control for blood glucose regulation in diabetic patients

The theory of H/sup /spl infin// optimal control has the feature of minimizing the worst-case gain of an unknown disturbance input. When appropriately modified, the theory can be used to design a "switching" controller that can be applied to insulin injection for blood glucose (BG) regulation. The "switching" controller is defined by a collection of basic insulin rates and a rule that switches the insulin rates from one value to another. The rule employed an estimation of BG from noisy measurements, and the subsequent optimization of a performance index that involves the solution of a "jump" Riccati differential equation and a discrete-time dynamic programming equation. With an appropriate patient model, simulation studies have shown that the controller could correct BG deviation using clinically acceptable insulin delivery rates.

Dynamic output feedback control of single-link flexible manipulators

This paper presents an efficient technique to design dynamic feedback control scheme for single-link flexible manipulators.  A linear model can be derived for the robotic system using the assumed-mode method.  Conventional techniques such as pole-placement or LQR require physical measurements of all systme states,  posing a stringent requirement for its implementation.  To overcome this problem, a low-order state functional observer is proposed here for reconstruction of the state feedback control action.  The observer design involves solving an optimisation problem with the objective to generate a feedback gain that is as close as possible to that of the required feedback controller.  A condition for robust stability of the closed-loop system under the observer-based control scheme is given.  The attractive features of the propsed technique are the resulted functional state observer is of a very low order and it requires only sensor measurements of only the output- the tip position of the arm.

Economic Evaluation of a Primary Care Trial to Reduce Weight Gain in Overweight/Obese Children: The LEAP Trial

Background:- A common policy response to the childhood obesity epidemic is to recommend that primary care physicians screen for and offer counseling to the overweight/obese. As the literature suggests, this approach may be ineffective; it is important to document the opportunity costs incurred by brief primary care obesity interventions that ultimately may not alter body mass index (BMI) trajectory.

Methods:- Live, Eat and Play (LEAP) was a randomized controlled trial of a brief secondary prevention intervention delivered by family physicians in 2002-2003 that targeted overweight/ mildly obese children aged 5 to 9 years. Primary care utilization was prospectively audited via medical records, and parents reported family resource use by written questionnaire. Outcome measures were BMI (primary) and parent-reported physical activity and dietary habits (secondary) in intervention compared with control children.

Results:- The cost of LEAP per intervention family was AU $4094 greater than for control families, mainly due to increased family resources devoted to child physical activity. Total health sector costs were AU $873 per intervention family and AU $64 per control, a difference of AU $809 {P < .001). At 15 months, intervention children did not differ significantly in adjusted BMI or daily physical activity scores compared with the control group, but dietary habits had improved.

Conclusions:- This brief intervention resulted in higher costs to families and the health care sector, which could have been devoted to other uses that do create benefits to health and/or family well-being. This has implications for countries such as the United States, the United Kingdom, and Australia, whose current guidelines recommend routine surveillance and counseling for high child BMI in the primary care sector.

Outcomes of a group-randomized trial to prevent excess weight gain, reduce screen behaviours and promote physical activity in 10-year-old children : switch-play

Objectives : To evaluate the effectiveness of an intervention to prevent excess weight gain, reduce time spent in screen behaviours, promote participation in and enjoyment of physical activity (PA), and improve fundamental movement skills among children.

Participants : In 2002, 311 children (78% response; 49% boys), average age 10 years 8 months, were recruited from three government schools in low socioeconomic areas of Melbourne, Australia.

Design : Group-randomized controlled trial. Children were randomized by class to one of the four conditions: a behavioural modification group (BM; n=66); a fundamental movement skills group (FMS; n=74); a combined BM/FMS group (BM/FMS; n=93); and a control (usual curriculum) group (n=62). Data were collected at baseline, post intervention, 6- and 12-month follow-up periods.

Results : BMI data were available for 295 children at baseline and 268 at 12-month follow-up. After adjusting for food intake and PA, there was a significant intervention effect from baseline to post intervention on age- and sex-adjusted BMI in the BM/FMS group compared with controls (-1.88 kg m-2, P<0.01), which was maintained at 6- and 12-month follow-up periods (-1.53 kg m-2, P<0.05). Children in the BM/FMS group were less likely than controls to be overweight/obese between baseline and post intervention (adjusted odds ratio (AOR)=0.36, P<0.05); also maintained at 12-month follow-up (AOR=0.38, P<0.05). Compared with controls, FMS group children recorded higher levels and greater enjoyment of PA; and BM children recorded higher levels of PA and TV viewing across all four time points. Gender moderated the intervention effects for participation in and enjoyment of PA, and fundamental movement skills.

Conclusion : This programme represents a promising approach to preventing excess weight gain and promoting participation in and enjoyment of PA. Examination of the mediators of this intervention and further tailoring of the programme to suit both genders is required.

Metabolic adaptations to short-term high-intensity interval training : a little pain for a lot of gain?

High-intensity interval training (HIT) is a potent time-efficient strategy to induce numerous metabolic adaptations usually associated with traditional endurance training. As little as six sessions of HIT over 2 wk or a total of only approximately 15 min of very intense exercise (~600 kJ), can increase skeletal muscle oxidative capacity and endurance performance and alter metabolic control during aerobic-based exercise.

Management control systems and effectiveness of knowledge sharing

Numerous empirical studies on knowledge management have examined the relative effectiveness of various enablers, such as organizational structure (Bennett and Gabriel, 1999; Gold et aI., 2001), technology (Gold et aI., 2001; O'Dell and Grayson, 1998), culture (DeLong and Fahey, 2000; Gupta and Govindarajan, 2000), managerial system (Nonaka, 1994; Sveiby, 1997) and strategy (Bierly and Chakrabarti, 1996; Holsapple and Joshi, 2001) on knowledge creation and sharing in organizations. Little research has focused on the role of management control systems (MCS) in facilitating knowledge sharing in knowledge-intensive firms (Ditillo, 2004). This study examines how the interactive use of management control systems (MCS) could facilitate the different modes of knowledge sharing among accounting professionals in Malaysia. Based on Nonaka's (1994) knowledge sharing mode, this study found a highly significant relationship between an interactive use of MCS and knowledge sharing to suggest that a more open, less fmancial-oriented and more interactive type of MCS tends to interlink and underpin organizational social process which is the central part of the knowledge sharing process. While professional accountants are generally keen to gain access to knowledge databases to source for possible task solutions, they are generally hesitant to share their tacit knowledge by transforming that knowledge into explicit form. The fmding suggests that there may be cultural-related factors that inhibit sharing of one's tacit knowledge totally and completely.

A low intensity, community based lifestyle programme to prevent weight gain in women with young children : cluster randomised controlled trial

Objective To develop and evaluate the effectiveness of a community behavioural intervention to prevent weight gain and improve health related behaviours in women with young children.
Design Cluster randomised controlled trial.
Setting A community setting in urban Australia. 
Participants 250 adult women with a mean age of 40. 39 years (SD 4.77, range 25-51) and a mean body mass index of 27.82 kg/m2 (SD 5.42, range 18-47) were recruited as clusters through 12 primary (elementary) schools. Intervention Schools were randomly assigned to the intervention or the control. Mothers whose schools fell in the intervention group (n=127) attended four interactive group sessions that involved simple health messages, behaviour change strategies, and group discussion, and received monthly support using mobile telephone text messages for 12 months. The control group (n=123)
attended one non-interactive information session based on population dietary and physical activity guidelines. 
Main outcome measures The main outcome measures were weight change and difference in weight change between the intervention group and the control group at 12 months. Secondary outcomes were changes in serum concentrations of fasting lipids and glucose, and changes in dietary behaviours, physical activity, and self management behaviours.
Results All analyses were adjusted for baseline values and the possible clustering effect. Women in the control group gained weight over the 12 month study period (0.83 kg, 95% confidence interval (CI) 0.12 to 1.54), whereas those in the intervention group lost weight (−0.20 kg, −0.90 to 0.49). The difference in weight change between the intervention group and the control group at 12 months was −1.13 kg (−2.03 to −0.24 kg; P<0.05) on the basis of observed values and −1.11 kg (−2.17 to −0.04) after multiple imputation to account for possible bias created by missing values. Secondary analyses after multiple imputation showed a difference in the intervention group compared with the control group for total cholesterol concentration (−0.35 mmol/l, −0.70 to −0.001), self management behaviours (diet score 0.18, 0.13 to 0.33; physical activity score 0.24, 0.05 to 0.43), and confidence to control weight (0.40, 0.11 to 0.69). Regular self weighing was associated with weight loss in the intervention group only (−1.98 kg, −3.75 to −0.23).
Conclusions Weight gain in women with young children could be prevented using a low intensity self management intervention delivered in a community setting. Self management of health behaviours improved with the intervention. The response rate of 12%, although comparable with that in other community studies, might limit the ability to generalise to other populations.    
Trial registration Australian New Zealand Clinical Trials Registry number ACTRN12608000110381.

Continuity of midwifery care and gestational weight gain in obese women : a randomised controlled trial

Background: The increased prevalence of obesity in pregnant women in Australia and other developed countries is a significant public health concern. Obese women are at increased risk of serious perinatal complications and guidelines recommend weight gain restriction and additional care. There is limited evidence to support the effectiveness of dietary and physical activity lifestyle interventions in preventing adverse perinatal outcomes and new strategies need to be evaluated. The primary aim of this project is to evaluate the effect of continuity of midwifery care on restricting gestational weight gain in obese women to the recommended range. The secondary aims of the study are to assess the impact of continuity of midwifery care on: women’s experience of pregnancy care; women’s satisfaction with care and a range of psychological factors.
Methods/Design: A two arm randomised controlled trial (RCT) will be conducted with primigravid women recruited from maternity services in Victoria, Australia. Participants will be primigravid women, with a BMI≥30 who are less than 17 weeks gestation. Women allocated to the intervention arm will be cared for in a midwifery continuity of care model and receive an informational leaflet on managing weight gain in pregnancy. Women allocated to the control group will receive routine care in addition to the same informational leaflet. Weight gain during pregnancy, standards of care, medical and obstetric information will be extracted from medical records. Data collected at recruitment (self administered survey) and at 36 weeks by postal survey will include sociodemographic information and the use of validated scales to measure secondary outcomes.
Discussion: Continuity of midwifery care models are well aligned with current Victorian, Australian and many international government policies on maternity care. Increasingly, midwifery continuity models of care are being introduced in low risk maternity care, and information on their application in high risk populations is required. There is an identified need to trial alternative antenatal interventions to reduce perinatal risk factors for women who are obese and the findings from this project may have application in other maternity services. In addition this study will inform a larger trial that will focus on birth and postnatal outcomes.

Behavior and weight correlates of weight-control efforts in Australian women living in disadvantage : the READI study

Background
With increasing obesity rates worldwide, more and more people are actively attempting to lose weight or avoid weight gain, but relatively little is known about what specific behaviors comprise these efforts and which, if any, are associated with better weight control over time.

Methods
This paper reports relationships between body weight, weight-control efforts and related behaviors over a three-year period in 1,634 Australian women. The women were purposefully recruited from 80 disadvantaged neighborhoods in Victoria, Australia. Weight loss efforts were categorized as trying to lose weight, trying to prevent weight gain and no weight-control efforts. Behavioral correlates examined included different kinds of physical activity and consumption of a number of specific foods types.

Results and discussion
Self-reported body weight at baseline was higher in women trying to lose weight. Frequency of consumption of low energy density foods was positively associated with reported weight-control efforts, as was frequency of reported total and leisure-time physical activity. Longitudinal associations between changes in weight-control efforts and changes in behaviors were consistent with the cross-sectional findings. At three-year follow up, however, weight-control efforts were not associated with change in body weight. More detailed analyses of specific food choices suggested that part of the explanation of no effect of reported weight-control efforts and weight over time might be that people are not as well-informed as they should be about the energy density of some common foods. In particular, those reporting engagement in weight-control efforts reported reducing consumption of carbohydrate-containing foods such as bread and potatoes more than is justified by their energy content, while they reported increasing consumption of some high energy density foods (e.g., cheese and nuts).

Conclusion
It is tentatively concluded that women living in disadvantaged neighborhoods understand messages about weight-control (more activity and foods with lower fat and lower energy density) but that some foods eaten more by women engaged in weight control may reduce the effectiveness of these efforts.

Observer-based control for time-varying delay neural networks with nonlinear observation

This paper studies the problem of designing observer-based controllers for a class of delayed neural networks with nonlinear observation. The system under consideration is subject to nonlinear observation and an interval time-varying delay. The nonlinear observation output is any nonlinear Lipschitzian function and the time-varying delay is not required to be differentiable nor its lower bound be zero. By constructing a set of appropriate Lyapunov-Krasovskii functionals and utilizing the Newton-Leibniz formula, some delay-dependent stabilizability conditions which are expressed in terms of Linear Matrix Inequalities (LMIs) are derived. The derived conditions allow simultaneous computation of two bounds that characterize the exponential stability rate of the closed-loop system. The unknown observer gain and the state feedback observer-based controller are directly obtained upon the feasibility of the derived LMIs stabilizability conditions. A simulation example is presented to verify the effectiveness of the proposed result.

Responsive façades : parametric control of moveable tilings

The challenge of developing adaptive, responsive low-energy architecture requires new knowledge about the complex and dynamic interaction between envelope architecture, optimization between competing environmental performance metrics (light, heat and wind indices) and local climate variables. Advances in modeling the geometry of building envelopes and control technologies for adaptive buildings now permit the sophisticated evaluation of alternative envelope configurations for a set of performance criteria. 

Testing the feasibility of a mobile technology intervention promoting healthy gestational weight gain in pregnant women (txt4two) - study protocol for a randomised controlled trial.

BACKGROUND: Overweight, obesity and excess gestational weight gain (GWG) are associated with negative health outcomes for mother and child in pregnancy and across the life course. Interventions promoting GWG within guidelines report mixed results. Most are time and cost intensive, which limits scalability. Mobile technologies (mHealth) offer low cost, ready access and individually-tailored support. We aim to test the feasibility of an mHealth intervention promoting healthy nutrition, physical activity and GWG in women who begin pregnancy overweight or obese. METHODS/DESIGN: txt4two is a parallel randomised control trial pilot recruiting women with a singleton, live gestation between 10(+0) and 17(+6) weeks at the first hospital antenatal clinic visit. Inclusion criteria are pre-pregnancy BMI > 25 kg/m(2) and mobile phone ownership. One hundred consenting women will be randomised to intervention or control groups at a 1:1 ratio. All participants will receive standard antenatal care. In addition, the txt4two intervention will be delivered from baseline to 36 weeks gestation and consists of a tailored suite of theoretically-grounded, evidence-based intervention strategies focusing on healthy nutrition, physical activity and GWG. This includes: mobile phone interactive text messages promoting positive health behaviours, goal setting and self-monitoring; video messages; an information website; and a private moderated Facebook® chat forum. The primary outcome is the feasibility of the intervention. Secondary outcomes include GWG and participants' knowledge and behaviour regarding diet and physical activity during pregnancy. DISCUSSION: Findings will inform the development of larger-scale mHealth programmes to improve the delivery of healthy pregnancy nutrition, physical activity and GWG, that could be widely translated and disseminated. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRNU111111544397 . Date of registration: 19 March 2014.

Nutritional intervention to prevent weight gain in patients commenced on olanzapine: a randomized controlled trial

Objective: Olanzapine is the most commonly prescribed atypical antipsychotic medication in Australia. Research reports an average weight gain of between 4.5 and 7 kg in the 3 months following its commencement. Trying to minimize this weight gain in a population with an already high prevalence of obesity, mortality and morbidity is of clinical and social importance. This randomized controlled trial investigated the impact of individual nutrition education provided by a dietitian on weight gain in the 3 and 6 months following the commencement of olanzapine.


Method: Fifty-one individuals (29 females, 22 males) who had started on olanzapine in the previous 3 months (mean length of 27 days ± 20) were recruited through Peninsula Health Psychiatric Services and were randomly assigned to either the intervention (n = 29) or the control group (n = 22). Individuals in the intervention group received six 1 hour nutrition education sessions over a 3-month period. Weight, waist circumference, body mass index (BMI) and qualitative measures of exercise levels, quality of life, health and body image were collected at baseline at 3 and 6 months.


Results: After 3 months, the control group had gained significantly more weight than the treatment group (6.0 kg vs 2.0 kg, p ≤ 0.002). Weight gain of more than 7% of initial weight occurred in 64% of the control group compared to 13% of the treatment group. The control group's BMI increased significantly more than the treatment group's (2 kg/m2vs 0.7 kg/m2, p ≤ 0.03). The treatment group reported significantly greater improvements in moderate exercise levels, quality of life, health and body image compared to the controls. At 6 months, the control group continued to show significantly more weight gain since baseline than the treatment group (9.9 kg vs 2.0 kg, p ≤ 0.013) and consequently had significantly greater increases in BMI (3.2 kg/m2vs 0.8 kg/m2, p ≤ 0.017).

Can a health coaching intervention delivered during pregnancy help prevent excessive gestational weight gain?

This study evaluated: (1) the efficacy of a health coaching (HC) intervention designed to prevent excessive gestational weight gain (GWG); and (2) whether there were improved psychological, motivational, and behavioural outcomes for women in the HC intervention compared to a "usual care" control group. In this quasi-experimental study, 267 pregnant women ≤18 weeks gestation were recruited between August 2011 and June 2013 from two hospital antenatal clinics in Melbourne, Australia. Intervention women received four individual HC and two group HC/educational sessions informed by theories of behaviour change. Women completed questionnaires assessing psychological, motivational and behavioural outcomes at 16-18 (baseline) and 33 (post-intervention) weeks gestation. Weight measures were collected. Compared to usual care, the intervention did not limit GWG or prevent excessive GWG. However, HC women reported greater use of active coping skills post-intervention. Despite lack of success of the HC intervention, given the risks associated with excessive weight gain in pregnancy, health professionals should continue to recommend appropriate GWG.

Colon cancer surveillance in inflammatory bowel disease: unclear gain but no psychological pain?

BACKGROUND: Surveillance for colorectal neoplasia in inflammatory bowel disease (IBD) is widely practised despite a lack of convincing mortality reduction. The psychological impact of this approach is largely unexplored. AIM: To examine psychological well-being among IBD subjects undergoing colonoscopic surveillance for colorectal cancer (CRC). METHODS: A cross-sectional study was performed by interrogating an IBD database for subjects currently enrolled in colonoscopic surveillance programmes. Identified surveillance subjects were age- and gender-matched with IBD control subjects not meeting surveillance criteria. Subjects were mailed a questionnaire including demographic details, the Short Form 36 (SF-36) survey to assess quality of life, the Spielberger State-Trait Personality Inventory, the Multidimensional Health Locus of Control, and a Risk Perception Questionnaire. RESULTS: One hundred and thirty-nine of 286 (49%) subjects responded, 53% male, 46% Crohn disease. Fifty-six per cent respondents were in the surveillance group. Surveillance subjects were older (55.4 vs 51.1 years; P = .048) with longer disease duration, but otherwise had comparable demographics with controls. Overall, quality of life was not significantly different between cohorts (mean SF-36 63.82 vs 65.48; P = 0.70). Groups did not differ on any locus of control classification (P = 0.52), nor was there any difference between mean scores on 'state' subscales of the Spielberger State-Trait Personality Inventory: anxiety (P = 0.91), curiosity (P = 0.12), anger (P = 0.81) or depression (P = 0.70). Both groups grossly overestimated their perceived lifetime risk of CRC at 50%, with no difference between surveillance and control subjects (P = 1.0). CONCLUSIONS: Enrolment in colonoscopic colon cancer surveillance does not appear to impair psychological well-being in individuals with IBD despite longer disease duration. IBD patients overestimate their risk of CRC.