Adrenoceptor influences on fluid and electrolyte transport in the rat intestine

An investigation of rat jejunal and distal colonic electrolyte transport in-vitro was undertaken using an Ussing chamber prepartion. Selective α2-adrenoceptor stimualtion in the jejunum was found to depress theo-phylline elevated anion secretion, as evidenced by decreases in short- circuit current (SCC). or α1 -Adrenoceptor stimulation, after α2 -adrenoceptor antagonism in the jejunum, evoked transient increases in basal anion secretion, as reflected by transient increases in basal SCC. The use of the neurotoxin tetrodotoxin indicated that this was a direct epithelial secretory effect. 5-hydroxytryptamine (5-HT) on the jejunum elicited transient increases in basal anion secretion, as demonstrated by transient increases in basal SCC. The use of tetrodotoxin, reserpine and α1 -adrenoceptor antagonists, indicated that a major component of this epithelial secretory effect by 5-HT, was associated with activation of intramural nervous pathways of the sympathetic nervous system, ultimately stimulating α1-adrenoceptors. This might represent an important secretory mechanism by 5-HT in the jejunum. β2-Adrenoceptor stimulation in the distal colon was found to decrease basal SCC, as evidenced by the metoprolol resistant effect of the selective β2- adrenoceptor agonist salbutamol, and lack of effect of the selective β1-adrenoceptor agonist prenalterol. An investigation of rat distal colonic fluid and electrolyte transport in-vivo was undertaken using an colonic loop technique. Although a basal colonic absorption of Na+ and Cl-, and a secretion of K+ were observed, these processes were not under tonic α-adrenergic regulation, as evidenced by the lack of effect of selective α-adrenoceptor antagonism. The secretory effects of prostaglandin-E2 were inhibited by α-adrenoceptor activation, whereas such stimulation did not evoke pro-absorptive responses upon basal transport, unlike noradrenaline.

Influences on general practitioner prescribing with particular reference to community pharmacy

Influences on general practitioner prescribing of drugs continue to be of interest and importance as cost containment becomes central to Government health policy. This thesis employs a plurality of research methods including quantitative and qualitative survey techniques for example, questionnaires, interviews and prescription analyses to investigate some of the factors which may influence GP prescribing such as information sources, hospital consultants and in particular the community pharmacist. When the use and influence of drug information sources by GPs was examined, the community pharmacist was given a relatively low rating as a source but a high rating, similar to that of the consultant, for helpfulness. Influences are needed to improve prescribing and reduce the incidence of iatrogenic disease for the benefit of the patient. The education and expertise of pharmacists and their familiarity with local prescribing habits places them in a unique position to meet the needs of local GPs. As 96.5% of the public always or nearly always take their prescriptions to the same pharmacy, patient medication records, now kept by 77.5% of pharmacies, provide a valuable check on the appropriateness and safety of patients' medication. The barriers to the pharmacist's greater involvement were shown to be suspicion by GPs of pharmacists' motivation, isolation of many community pharmacists, difficulties in leaving the pharmacy for domiciliary visits, residential home care and GP practice meetings. These barriers must be lowered if the pharmacist is to have a greater influence and involvement. It was concluded that changes are necessary in pharmaceutical education, staff training, organisation and remuneration. Some changes in the targeting of remuneration to the pharmaceutical care services provided and registration of patients with pharmacies would contribute greatly to these aims.

Molecular architecture influences on material properties of pharmaceutical compounds

Salt formation has extensively been studied as a strategy to improve drug solubility but it has not been explored as a strategy to improve mechanical properties. A better understanding of which factors of the solid state can have an influence in the mechanical properties of pharmaceutical powders can help to optimise and reduce cost of tablet manufacturing. The aim of this study was to form different series of amine salts of flurbiprofen, gemfibrozil and diclofenac and to establish predictive relationships between architectural characteristics and physicochemical and mechanical properties of the salts. For this purpose, three different carboxylic acid drugs were selected: flurbiprofen, gemfibrozil and diclofenac, similar in size but varying in flexibility and shape and three different series of counterions were also chosen: one with increasing bulk and no hydroxyl groups to limit the hydrogen bonding potential; a second one with increasing number of hydroxyl groups and finally a third series, related to the latter in number of hydroxyl groups but with different molecular shape and flexibility. Physico-chemical characterization was performed (DSC, TGA, solubility, intrinsic dissolution rate, particle size, true density) and mechanical properties measured using a compaction replicator. Strained molecular conformations produce weaker compacts as they have higher energy than preferred conformations that usually lie close to energy minimums and oppose plastic deformation. It was observed that slip planes, which correspond to regions of weakest interaction between the planes, were associated with improved plasticity and stronger compacts. Apart from hydrogen bonds, profuse van der Waals forces can result in ineffective slip planes. Salts displaying two-dimensional densely hydrogen bonded layers produced stronger compacts than salts showing one-dimensional networks of non-bonded columns, probably by reducing the attachment energy between layers. When hydrogen bonds are created intramolecularly, it is possible that the mechanical properties are compromised as they do not contribute so much to create twodimensional densely bonded layers and they can force molecules into strained conformations. Some types of hydrogen bonding network may be associated with improved mechanical properties, such as type II, or R (10) 3 4 using graph-set notation, versus type III, or R (12) 4 8 , columns. This work clearly demonstrates the potential of investigating crystal structure-mechanical property relationship in pharmaceutical materials.

How does bureaucracy impact individual creativity? A cross-level investigation of team contextual influences on goal orientation-creativity relationships

Offering important counterpoint to work identifying team influences stimulating creative expression of individual differences in goal orientation, we develop cross-level theory establishing that team bureaucratic practices (centralization and formalization) constrain creative expression. Speaking to the tension between bureaucracy and creativity, findings indicate that this influence is not only negative and that effects of centralization and formalization differ. Surveying 330 employees in 95 teams at the Taiwan Customs Bureau, we found that learning and "performance avoid" goal orientations had, respectively, stronger positive and weaker negative relationships with creativity under low centralization. A "performance- prove" orientation was positively related to creativity under low formalization. © Academy of Management Journal.

Pleasure, pain and procrastination:reflections on the experience of doing memory-work research

The focus of this article is the process of doing memory-work research. We tell the story of our experience of what it was like to use this approach. We were enthused to work collectively on a "discovery" project to explore a method with which we were unfamiliar. We hoped to build working relationships based on mutual respect and the desire to focus on methodology and its place in our psychological understanding. The empirical activities highlighted methodological and experiential challenges, which tested our adherence to the social constructionist premise of Haug's original description of memory work. Combined with practical difficulties of living across Europe, writing and analyzing the memories became contentious. We found ourselves having to address a number of tensions emanating from the work and our approach to it. We discuss some of these tensions alongside examples that illustrate the research process and the ways we negotiated the collective nature of the memory-work approach. © 2012 Copyright Taylor and Francis Group, LLC.

Parental influences on children's eating behaviour and characteristics of successful parent-focussed interventions

Parental reports suggest that difficulties related to child-feeding and children's eating behaviour are extremely common. While 'fussy eating' does not pose an immediate threat to health, over the long-term, consumption of a poor diet can contribute to the development of a range of otherwise preventable diseases. In addition, the stress and anxiety that can surround difficult mealtimes can have a detrimental impact upon both child and parental psychological wellbeing. Since parents have a great influence over what, when, and how much food is offered, feeding difficulties may be preventable by better parental awareness. The aim of this review is to describe how parental factors contribute to the development of common feeding problems, and to discuss the merits of existing interventions aimed at parents/primary caregivers to improve child-feeding and children's eating behaviour. The potential for different technologies to be harnessed in order to deliver interventions in new ways will also be discussed. © 2012 Elsevier Ltd.

Peer and friend influences on children's eating

Peers and friends are perceived as important role models for the formation of children's attitudes and behaviours. A wealth of research has aimed to establish the contribution of peers and friends to children's developing eating behaviours, and their attitudes towards eating. This review describes and evaluates such research. Experimental research examining peer modelling of food consumption and liking is reviewed, and several individual child factors that are suggested to make children more or less receptive to peer and friend influences are discussed. The influence of children's perceptions of their peers' and friends' eating behaviours upon their own eating practices is also explored. The benefits of future longitudinal research to improve understanding of peer and friend influences on children's eating are emphasized. © 2013 John Wiley & Sons Ltd.

Nutritional influences on cognitive function:mechanisms of susceptibility

The impact of nutritional variation, within populations not overtly malnourished, on cognitive function and arousal is considered. The emphasis is on susceptibility to acute effects of meals and glucose loads, and chronic effects of dieting, on mental performance, and effects of cholesterol and vitamin levels on cognitive impairment. New developments in understanding dietary influences on neurohormonal systems, and their implications for cognition and affect, allow reinterpretation of both earlier and recent findings. Evidence for a detrimental effect of omitting a meal on cognitive performance remains equivocal: from the outset, idiosyncrasy has prevailed. Yet, for young and nutritionally vulnerable children, breakfast is more likely to benefit than hinder performance. For nutrient composition, despite inconsistencies, some cautious predictions can be made. Acutely, carbohydrate-rich–protein-poor meals can be sedating and anxiolytic; by comparison, protein-rich meals may be arousing, improving reaction time but also increasing unfocused vigilance. Fat-rich meals can lead to a decline in alertness, especially where they differ from habitual fat intake. These acute effects may vary with time of day and nutritional status. Chronically, protein-rich diets have been associated with decreased positive and increased negative affect relative to carbohydrate-rich diets. Probable mechanisms include diet-induced changes in monoamine, especially serotoninergic neurotransmitter activity, and functioning of the hypothalamic pituitary adrenal axis. Effects are interpreted in the context of individual traits and susceptibility to challenging, even stressful, tests of performance. Preoccupation with dieting may impair cognition by interfering with working memory capacity, independently of nutritional status. The change in cognitive performance after administration of glucose, and other foods, may depend on the level of sympathetic activation, glucocorticoid secretion, and pancreatic β-cell function, rather than simple fuelling of neural activity. Thus, outcomes can be predicted by vulnerability in coping with stressful challenges, interacting with nutritional history and neuroendocrine status. Functioning of such systems may be susceptible to dietary influences on neural membrane fluidity, and vitamin-dependent cerebrovascular health, with cognitive vulnerability increasing with age.

Technology influences on small logistics providers:a case study analysis

ICT has triggered many changes in the logistics service industry. New technology is reshaping the organisation and structure of this industry as ICT impacts significantly on the operations of 3PLs. Within this process, while large 3PLs are gaining substantial benefits from technology usage, the nature of changes resulting from ICT usage in small 3PLs remains unclear. This is critical particularly for those markets populated by a high number of small 3PLs such as the Italian logistics industry. From the research point of view, there is still a gap in the literature where the role of technological capability in small 3PLs are seriously underestimated. This gives rise to the need to develop investigation in this area. This paper presents the preliminary results of a case study analysis on ICT usage in a sample of 7 small Italian 3PLs. The results highlight some of the barriers to effective ICT implementation, as well as some of the critical success factors.

Systemic circulatory influences on retinal microvascular function in middle-age individuals with low to moderate cardiovascular risk

Purpose: To investigate the relationship between retinal microvascular reactivity, circulatory markers for CVD risk and systemic antioxidative defence capacity in healthy middle-aged individuals with low to moderate risk of CVD. Methods: Retinal vascular reactivity to flickering light was assessed in 102 healthy participants (46-60 years) by means of dynamic retinal vessel analysis (DVA). Other vascular assessments included carotid intima-media thickness (C-IMT) and blood pressure (BP) measurements. Total cholesterol (CHOL), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and blood glutathione levels in its reduced (GSH) and oxidized (GSSG) forms were also determined for each participant, along with Framingham risk scores (FRS). Results: Retinal arterial baseline diameter fluctuation (BDF) was independently, significantly and negatively influenced by LDL-C levels (β = -0.53, p = 0.027). Moreover, the arterial dilation slope (SlopeAD) was independently, significantly and positively associated with redox index (GSH: GSSG ratio, β = 0.28, p = 0.016), while the arterial constriction slope (SlopeAC) was significantly and negatively influenced by blood GSH levels (β = -0.20, p = 0.042), and positively associated with FRS (β = 0.25, p = 0.009). Venous BDF and dilation amplitude (DA) were also negatively influenced by plasma LDL-C levels (β = -0.83, p = 0.013; and β = -0.22, p = 0.028, respectively). Conclusions: In otherwise healthy individuals with low to moderate cardiovascular risk, retinal microvascular dilation and constriction responses to stress levels are influenced by systemic antioxidant capacity, and circulating markers for cardiovascular risk.

Social and individual influences on eating in preadolescents:the role of friends’ eating behaviours and individual anxiety and depression

Background: Friends are important role models for the formation of social norms and behaviour comparisons, particularly in children. This study examined the similarities between pre-adolescent children’s own eating behaviours with the eating behaviours of those in their friendship group. It also evaluated whether symptoms of anxiety and depression were related to eating behaviours in this age group. Methods: Three hundred and forty three children (mean age 8.75 years) completed questionnaires designed to measure dietary restraint, emotional eating and external eating, as well as general and social anxiety, and symptoms of depression. Children also provided details about their friendship groups. Results: Pre-adolescents’ dietary restraint was positively predicted by the dietary restraint of members of their friendship groups, and their individual levels of anxiety and depression. The levels of general anxiety exhibited by pre-adolescents predicted emotional and external eating behaviours. Younger children were significantly more likely to report higher levels of emotional and external eating than older children, and boys were more likely to report more external eating behaviours than girls. Conclusions: These results suggest that greater dieting behaviours in pre-adolescents are related to their friends’ reports of greater dieting behaviours. In contrast, greater levels of eating governed by emotions, and eating in response to external hunger cues, are related to greater symptoms of anxiety in pre-adolescent children. Such findings underline the importance of friends’ social influences on dieting behaviours in this age group and highlight the value of targeting healthy eating and eating disorder prevention interventions at pre-adolescents.

Phylogenetic and ontogenetic influences on the distribution of anthocyanins and betacyanins in leaves of tropical plants

We examined the anatomy of expanding, mature, and senescing leaves of tropical plants for the presence of red pigments: anthocyanins and betacyanins. We studied 463 species in total, 370 genera, belonging to 94 families. This included 21 species from five families in the Caryophyllales, where betacyanins are the basis for red color. We also included 14 species of ferns and gymnosperms in seven families and 29 species with undersurface coloration at maturity. We analyzed 399 angiosperm species (74 families) for factors (especially developmental and evolutionary) influencing anthocyanin production during expansion and senescence. During expansion, 44.9% produced anthocyanins and only 13.5% during senescence. At both stages, relatively few patterns of tissue distributions developed, primarily in the mesophyll, and very few taxa produced anthocyanins in dermal and ground tissue simultaneously. Of the 35 species producing anthocyanins both in development and senescence, most had similar cellular distributions. Anthocyanin distributions were identical in different developing leaves of three heteroblastic taxa. Phylogeny has influenced the distribution of anthocyanins in the epidermis and mesophyll of expanding leaves and the palisade parenchyma during senescence, although these influences are not strong. Betacyanins appear to have similar distributions in leaves of taxa within the Caryophyllales and, perhaps, similar functions. The presence of anthocyanins in the mesophyll of so many species is inconsistent with the hypothesis of protection against UV damage or fungal pathogens, and the differing tissue distributions indicate that the pigments may function in different ways, as in photoprotection and freeradical scavenging.

Influences on immigrant students' perceptions of the chances of making it in the United States

This study examined immigrant minority students' perceptions of race relations and of the chances for social mobility in the United States (U.S.) using cohort samples of West Indian (N = 173) and Haitian (N = 191) students. The Students' responses collected during the 6th and 7th, 8th and 9th grades were analyzed to determine whether perceptions of racial mistrust, teacher derogation and social mobility varied depending on the student's length of stay in the U.S. or self-concept. Quantitative methodology was applied to data extrapolated from a larger epidemiological longitudinal study consisting of 7,386 middle school students in Miami (Vega and Gil, 1998). ^ Results show that West Indian and Haitian students' perceptions of racial mistrust, teacher derogation and social mobility were associated more with student's self-concept than length of stay. Students with more favorable self-concepts reported greater optimism toward social mobility than those with less favorable self-concepts. Results also indicate that in the context of parental education and SES that racial mistrust is the strongest predictor of these students' level of optimism towards social mobility. ^

The impact of information technology on organizations: A study of enterprise resource planning system influences on job design and organizational culture

The primary purpose of this research is to study the linkage between perceived job design characteristics and information system environment characteristics before and after the replacement of a legacy information system with a new type of information system (referred to as an Enterprise Resource Planning or ERP system). A public state University implementing an academic version of an ERP system was selected for the study. Three survey instruments were used to examine the perception of the information system, the job characteristics, and the organizational culture before and after the system implementation. The research participants included two large departments resulting in a sample of 130 workers. Research questions were analyzed using multivariate procedures including factor analysis, path analysis, step-wise regression, and matched pair analysis. ^ Results indicated that the ERP system has introduced new elements into the working environment that has changed the perception of how the job design characteristics and organization culture dimensions are viewed by the workers. The understanding of how the perceived system characteristics align with an individual's perceived job design characteristics is supported by each of the system characteristics significantly correlated in the proposed direction. The stronger support of this relationship becomes visible in the causal flow of the effects seen in the path diagram and in the step-wise regression. The perceived job design characteristics aligning with dimensions of organizational culture are not as strong as the literature suggests. Although there are significant correlations between the job and culture variables, only one relationship can be seen in the causal flow. ^ This research has demonstrated that system characteristics of ERP do contribute to the perception of change in an organization and do support organizational culture behaviors and job characteristics. ^