Optimization algorithms and ODE's in MDO

There is a need for a stronger theoretical understanding of Multidisciplinary Design Optimization (MDO) within the field. Having developed a differential geometry framework in response to this need, we consider how standard optimization algorithms can be modeled using systems of ordinary differential equations (ODEs) while also reviewing optimization algorithms which have been derived from ODE solution methods. We then use some of the framework's tools to show how our resultant systems of ODEs can be analyzed and their behaviour quantitatively evaluated. In doing so, we demonstrate the power and scope of our differential geometry framework, we provide new tools for analyzing MDO systems and their behaviour, and we suggest hitherto neglected optimization methods which may prove particularly useful within the MDO context. Copyright © 2013 by ASME.

Reproductive seasonality and maturity of male Neophocaena phocaenoides asiaeorientalis in captivity: A case study based on the hormone evidence

To provide hormone evidence on reproductive seasonality and maturity of the Yangtze finless porpoise, the authors monitored the monthly variations of serum reproductive hormones of a male Yangtze finless porpoise in captivity via radioimmunoassay from 1997 to 2003. It was demonstrated that the immature animal had a serum T level of 28-101ngdL -1 (6552ngdL -1 ), reached puberty with the serum T concentration ranging between 250 and 590ngdL -1 (390130ngdL -1 ), and attained reproductive maturity when the serum T level went beyond 1120180ngdL -1 in the breeding season. The body length growth of the animal showed a pattern similar to the serum T variations during its adolescent period from the age of 4 to 6 years. Moreover, the serum T concentration of the male porpoise exhibited significant seasonal variations, indicating that its breeding season may start as early as March and end as late as September.

Morphologies and physical properties of PA1010/HIPS/HIPS-g-MA ternary blends

The effect of the content of a copolymer consisting of high impact polystyrene grafted with maleic anhydride (HIPS-g-MA) on morphological and mechanical properties of PA1010/HIPS blends has been studied. Blend morphologies were controlled by adding HIPS-g-MA during melt processing, thus the dispersion of the HIPS phase and interfacial adhesion between the domains and matrices in these blends were changed obviously. The weight fractions of HIPS-g-MA in the blends increased from 2.5 to 20, then much finer dispersions of discrete HIPS phase with average domain sizes decreased from 6.1 to 0.1 mu m were obtained. It was found that a compatibilizer, a graft copolymer of HIPS-g-MA and PA1010 was synthesized in situ during the melt mixing of the blends. The mechanical properties of compatibilized blends were obviously better than those of uncompatibilized PA1010/HIPS blends. These behaviors could be attributed to the chemical interactions between the two components of PA1010 and HIPS-g-MA and good dispersion in PA1010/HIPS/HIPS-g-MA blends. Evidence of reactions in the blends was seen in the morphology and mechanical behaviour of the solid. The blend containing 5 wt % HIPS-g-MA component exhibited outstanding toughness. (C) 1999 Kluwer Academic Publishers.

On morphology and the competition between crystallization and phase separation in polypropylene-polyethylene blends

Blends of polypropylene (PP) and low density polyethylene (LDPE) have been examined for a series of compositions using differential scanning calorimetry and permanganic etching followed by transmission electron microscopy. Thermal analysis of their melting and recrystallization behaviour suggests two possibilities, either that below 15 wt % PP the blends are fully miscible and that PP only crystallizes after LDPE because of compositional changes in the remaining melt, or else that the PP is separated, but in the form of droplets too small to crystallize at normal temperatures. Microscopic examination of the morphology shows that the latter is the case, but that a fraction of the PP is nevertheless dissolved in the LDPE. (C) 1998 Kluwer Academic Publishers.

VISCOSITY AND FLOW PROPERTIES OF CONCENTRATED-SOLUTIONS OF CHITOSAN WITH DIFFERENT DEGREES OF DEACETYLATION

The effects of the degree of deacetylation (DD) on the viscosity and flow behaviour of concentrated solutions of chitosan were investigated using 0.2 M CH3COOH and 0.2 M CH3COOH/0.1 M CH3COONa aqueous solutions as solvents. The results indicated that the

THE COMPATIBILITY AND CRYSTALLIZATION OF THE MIXTURES OF POLY (TETRAHYDROFURAN-b-METHYL METHACRYLATE) DIBLOCK COPOLYMER WITH POLYVINYL CHLORIDE HOMOPOLYMER

The compatibility and crystallization behaviour of the mixtures of poly (tetrahydrofuran-methyl methacrylate) diblock copolymer (PTHF-b-PMMA) with polyvinyl chloride has been studied. We found that the compatibility of these blends, in which there is special interaction between the homopolymer and the PMMA block of the copolymer, is much better than that of the AB/A type blends; and that the crystallization rate and crystallinity of PTHF microdomain changed greatly due to the swollen by PVC homopolymer. In this paper, these changes in cryatallization are well explained according to the theories of block copolymer blends and the density gradient model presented by JIANG Ming.

ELECTROCHEMICAL STUDY OF ISOPOLY AND HETEROPOLY OXOMETALLATE FILM MODIFIED MICROELECTRODES .5. PREPARATION AND ELECTROCHEMICAL-BEHAVIOR OF A 2/18-MOLYBDODIPHOSPHATE ANION MONOLAYER MODIFIED ELECTRODE

In this paper a carbon fibre (CF) microelectrode modified with the 2:18-molybdodiphosphate anion by simple adsorption is described and its electrochemical behaviour is reported. The 2:18-molybdodiphosphate anion (alpha-P2Mo18O626-), which is a Dawson structure, undergoes five successive multielectron reductions in acidic solution. The first three redox waves correspond to the two-electron process, and the last two waves are four-electron and six-electron processes respectively. On the basis of the experimental results it is shown that the electrode process of alpha-P2Mo18O626- on the CF electrode in acidic solution is simultaneously controlled by the diffusion and adsorption of alpha-P2Mo18O626- anions. When the concentration of the alpha-P2Mo18O626- in the solution is reduced, the electrode process mainly exhibits non-diffusion-controlled behaviour, and the diffusion-limited process takes over as the concentration of alpha-P2Mo18O626- becomes higher. The CF electrode modified with a thin film of alpha-P2Mo18O626- exhibits very good stability and redox behaviour in aqueous acidic solution. The alpha-P2Mo18O626- is reduced to heteropoly blue, with an accompanying protonation process. The addition of more than six electrons to the alpha-P2Mo18O626- anion in an aqueous solution does not result in its decomposition. The result obtained is not the same as that reported previously.

THE CHARACTERIZATION OF 2 COPPER PHTHALOCYANINE LANGMUIR-BLODGETT-FILMS AND THEIR GAS-SENSITIVE PROPERTIES

The monolayer and deposition behaviour of a symmetrically substituted copper tetra-4-(2, 4-di-t-amylphenoxy) phthalocyanine (tapCuPc) and an asymmetrically substituted copper [tri-4-(2, 4-di-t-amylphenoxy)-mono-4-(-2-methoxyethoxy)]phthalocyanine (AsyCuPc) were investigated. The results on monolayer behaviour and spectroscopic characterization of the LB films show that both CuPc molecules in a monolayer at the air-water interface and the LB films are stacked and inclined. The gas-sensitive properties show that the responding speed of AsyCuPc LB film is faster than that of tapCuPc LB film.

DYNAMIC SCALING AND FRACTAL BEHAVIOR OF SPINODAL PHASE-SEPARATION IN POLYMER MIXTURES OF POLY(METHYL METHACRYLATE) WITH POLY(STYRENE-CO-ACRYLONITRILE)

Dynamic scaling and fractal behaviour of spinodal phase separation is studied in a binary polymer mixture of poly(methyl methacrylate) (PMMA) and poly(styrene-co-acrylonitrile) (SAN). In the later stages of spinodal phase separation, a simple dynamic scaling law was found for the scattering function S(q,t):S(q,t) approximately q(m)-3S approximately (q/q(m)). The possibility of using fractal theory to describe the complex morphology of spinodal phase separation is discussed. In phase separation, morphology exhibits strong self-similarity. The two-dimensional image obtained by optical microscopy can be analysed within the framework of fractal concepts. The results give a fractal dimension of 1.64. This implies that the fractal structure may be the reason for the dynamic scaling behaviour of the structure function.

Behavioural responses by yaks in different physiological states (lactating, dry or replacement heifers), when grazing natural pasture in the spring (dry and germinating) season on the Qinghai-Tibetan plateau

Using heterogeneous vegetation in alpine grassland through grazing is a necessary component of deintensification of livestock systems and conservation of natural environments. However, better understanding of the dynamics of animal feeding behaviour would improve pasture and livestock grazing managements, particularly in the early part of the spring season when forage is scarce. The changes in behaviour may improve the use of poor pastures. Then, enhancing management practices may conserve pasture and improve animal productivity. Grazing behaviour over 24 In periods by yaks in different physiological states (lactating, dry and replacement heifers) was recorded in the early, dry and later, germinating period of the spring season. Under conditions of inadequate forage, the physiological state of yaks was not the primary factor affecting their grazing and ruminating behaviour. Forage and sward state affected yaks' grazing and ruminating behaviour to a greater extent. Generally, yaks had higher intake and spent more time grazing and ruminating during the later part of the spring season, following germination of forage, than during the earlier dry part of the season. However, the live weight of yaks was less during pasture germination than during the early dry part of the season because the herbage mass is low, and the yaks have to expend much energy to seek feed at this particular time. (c) 2007 Elsevier B.V. All rights reserved.

Group size effects on foraging and vigilance in migratory Tibetan antelope

Large group sizes have been hypothesized to decrease predation risk and increase food competition. We investigated group size effects on vigilance and foraging behaviour during the migratory period in female Tibetan antelope Pantholops hodgsoni, in the Kekexili Nature Reserve of Qinghai Province, China. During June to August, adult female antelope and yearling females gather in large migratory groups and cross the Qinghai-Tibet highway to calving grounds within the Nature Reserve and return to Qumalai county after calving. Large groups of antelope aggregate in the migratory corridor where they compete for limited food resources and attract the attention of mammalian and avian predators and scavengers. We restricted our sampling to groups of less than 30 antelopes and thus limit our inference accordingly. Focal-animal sampling was used to record the behaviour of the free-ranging antelope except for those with lambs. Tibetan antelope spent more time foraging in larger groups but frequency of foraging bouts was not affected by group size. Conversely, the time spent vigilant and frequency of vigilance bouts decreased with increased group size. We suggest that these results are best explained by competition for food and risk of predation. (C) 2007 Elsevier B.V. All rights reserved.

Examining the post-adoptive infusion of mobile technology in a healthcare domain: determinants and outcomes

The healthcare industry is beginning to appreciate the benefits which can be obtained from using Mobile Health Systems (MHS) at the point-of-care. As a result, healthcare organisations are investing heavily in mobile health initiatives with the expectation that users will employ the system to enhance performance. Despite widespread endorsement and support for the implementation of MHS, empirical evidence surrounding the benefits of MHS remains to be fully established. For MHS to be truly valuable, it is argued that the technological tool be infused within healthcare practitioners work practices and used to its full potential in post-adoptive scenarios. Yet, there is a paucity of research focusing on the infusion of MHS by healthcare practitioners. In order to address this gap in the literature, the objective of this study is to explore the determinants and outcomes of MHS infusion by healthcare practitioners. This research study adopts a post-positivist theory building approach to MHS infusion. Existing literature is utilised to develop a conceptual model by which the research objective is explored. Employing a mixed-method approach, this conceptual model is first advanced through a case study in the UK whereby propositions established from the literature are refined into testable hypotheses. The final phase of this research study involves the collection of empirical data from a Canadian hospital which supports the refined model and its associated hypotheses. The results from both phases of data collection are employed to develop a model of MHS infusion. The study contributes to IS theory and practice by: (1) developing a model with six determinants (Availability, MHS Self-Efficacy, Time-Criticality, Habit, Technology Trust, and Task Behaviour) and individual performance-related outcomes of MHS infusion (Effectiveness, Efficiency, and Learning), (2) examining undocumented determinants and relationships, (3) identifying prerequisite conditions that both healthcare practitioners and organisations can employ to assist with MHS infusion, (4) developing a taxonomy that provides conceptual refinement of IT infusion, and (5) informing healthcare organisations and vendors as to the performance of MHS in post-adoptive scenarios.

Childhood obesity in Ireland: recent trends and modifiable determinants

Background: Childhood obesity is a global epidemic posing a significant threat to the health and wellbeing of children. To reverse this epidemic, it is essential that we gain a deeper understanding of the complex array of driving factors at an individual, family and wider ecological level. Using a social-ecological framework, this thesis investigates the direction, magnitude and contribution of risk factors for childhood overweight and obesity at multiple levels of influence, with a particular focus on diet and physical activity. Methods: A systematic review was conducted to describe recent trends (from 2002-2012) in childhood overweight and obesity prevalence in Irish school children from the Republic of Ireland. Two datasets (Cork Children’s Lifestyle [CCLaS] Study and the Growing Up in Ireland [GUI] Study) were used to explore determinants of childhood overweight and obesity. Individual lifestyle factors examined were diet, physical activity and sedentary behaviour. The determinants of physical activity were also explored. Family factors examined were parental weight status and household socio-economic status. The impact of food access in the local area on diet quality and body mass index (BMI) was investigated as an environmental level risk factor. Results: Between 2002 and 2012, the prevalence of childhood overweight and obesity in Ireland remained stable. There was some evidence to suggest that childhood obesity rates may have decreased slightly though one in four Irish children remained either overweight or obese. In the CCLaS study, overweight and obese children consumed more unhealthy foods than normal weight children. A diet quality score was constructed based on a previously validated adult diet score. Each one unit increase in diet quality was significantly associated with a decreased risk of childhood overweight and obesity. Individual level factors (including gender, being a member of a sports team, weight status) were more strongly associated with physical activity levels than family or environmental factors. Overweight and obese children were more sedentary and less active than normal weight children. There was a dose response relationship between time spent at moderate to vigorous physical activity (MVPA) and the risk of childhood obesity independent of sedentary time. In contrast, total sedentary time was not associated with the risk of childhood obesity independent of MVPA though screen time was associated with childhood overweight and obesity. In the GUI Study, only one in five children had 2 normal weight parents (or one normal weight parent in the case of single parent families). Having overweight and obese parents was a significant risk factor for overweight and obesity regardless of socio-economic characteristics of the household. Family income was not associated with the odds of childhood obesity but social class and parental education were important risk factors for childhood obesity. Access to food stores in the local environment did not impact dietary quality or the BMI of Irish children. However, there was some evidence to suggest that the economic resources of the family influenced diet and BMI. Discussion: Though childhood overweight and obesity rates appear to have stabilised over the previous decade, prevalence rates are unacceptably high. As expected, overweight and obesity were associated with a high energy intake and poor dietary quality. The findings also highlight strong associations between physical inactivity and the risk of overweight and obesity, with effect sizes greater than what have been typically found in adults. Important family level determinants of childhood overweight and obesity were also identified. The findings highlight the need for a multifaceted approach, targeting a range of modifiable determinants to tackle the problem. In particular, policies and interventions at the shared family environment or community level may be an effective mean of tackling this current epidemic.

Baby on board: olfactory cues indicate pregnancy and fetal sex in a non-human primate.

Olfactory cues play an integral, albeit underappreciated, role in mediating vertebrate social and reproductive behaviour. These cues fluctuate with the signaller's hormonal condition, coincident with and informative about relevant aspects of its reproductive state, such as pubertal onset, change in season and, in females, timing of ovulation. Although pregnancy dramatically alters a female's endocrine profiles, which can be further influenced by fetal sex, the relationship between gestation and olfactory cues is poorly understood. We therefore examined the effects of pregnancy and fetal sex on volatile genital secretions in the ring-tailed lemur (Lemur catta), a strepsirrhine primate possessing complex olfactory mechanisms of reproductive signalling. While pregnant, dams altered and dampened their expression of volatile chemicals, with compound richness being particularly reduced in dams bearing sons. These changes were comparable in magnitude with other, published chemical differences among lemurs that are salient to conspecifics. Such olfactory 'signatures' of pregnancy may help guide social interactions, potentially promoting mother-infant recognition, reducing intragroup conflict or counteracting behavioural mechanisms of paternity confusion; cues that also advertise fetal sex may additionally facilitate differential sex allocation.

The relationship between disgust sensitivity, anxiety and obsessions

Three hundred participants, including volunteers from an obsessional support group, filled in questionnaires relating to disgust sensitivity, health anxiety, anxiety, fear of death, fear of contamination and obsessionality as part of an investigation into the involvement of disgust sensitivity in types of obsessions. Overall, the data supported the hypothesis that a relationship does exist between disgust sensitivity and the targeted variables. A significant predictive relationship was found between disgust sensitivity and total scores on the obsessive compulsive inventory (OCI; Psychological Assessment 10 (1998) 206) for both frequency and distress of symptomatology. Disgust sensitivity scores were significantly related to health anxiety scores and general anxiety scores and to all the obsessional subscales, with the exception of hoarding. Additionally, multiple regression analyses revealed that disgust sensitivity may be more specifically related to washing compulsions: frequency of washing behaviour was best predicted by disgust sensitivity scores. Washing distress scores were best predicted by health anxiety scores, though disgust sensitivity entered in the second model. It is suggested that further research on the relationship between disgust sensitivity and obsessionality could be helpful in refining the theoretical understanding of obsessions.