127 research outputs found
Ignition of thermally sensitive explosives between a contact surface and a shock
The dynamics of ignition between a contact surface and a shock wave is investigated using a
one-step reaction model with Arrhenius kinetics. Both large activation energy asymptotics and
high-resolution finite activation energy numerical simulations are employed. Emphasis is on comparing
and contrasting the solutions with those of the ignition process between a piston and a shock,
considered previously. The large activation energy asymptotic solutions are found to be qualitatively
different from the piston driven shock case, in that thermal runaway first occurs ahead of
the contact surface, and both forward and backward moving reaction waves emerge. These waves
take the form of quasi-steady weak detonations that may later transition into strong detonation
waves. For the finite activation energies considered in the numerical simulations, the results are
qualitatively different to the asymptotic predictions in that no backward weak detonation wave
forms, and there is only a weak dependence of the evolutionary events on the acoustic impedance
of the contact surface. The above conclusions are relevant to gas phase equation of state models.
However, when a large polytropic index more representative of condensed phase explosives is used,
the large activation energy asymptotic and finite activation energy numerical results are found to
be in quantitative agreement
Towards Activity Context using Software Sensors
Service-Oriented Computing delivers the promise of configuring and
reconfiguring software systems to address user's needs in a dynamic way.
Context-aware computing promises to capture the user's needs and hence the
requirements they have on systems. The marriage of both can deliver ad-hoc
software solutions relevant to the user in the most current fashion. However,
here it is a key to gather information on the users' activity (that is what
they are doing). Traditionally any context sensing was conducted with hardware
sensors. However, software can also play the same role and in some situations
will be more useful to sense the activity of the user. Furthermore they can
make use of the fact that Service-oriented systems exchange information through
standard protocols. In this paper we discuss our proposed approach to sense the
activity of the user making use of software
Inhibition of Y1 receptor signaling improves islet transplant outcome
Failure to secrete sufficient quantities of insulin is a pathological feature of type-1 and type-2 diabetes, and also reduces the success of islet cell transplantation. Here we demonstrate that Y1 receptor signaling inhibits insulin release in β-cells, and show that this can be pharmacologically exploited to boost insulin secretion. Transplanting islets with Y1 receptor deficiency accelerates the normalization of hyperglycemia in chemically induced diabetic recipient mice, which can also be achieved by short-term pharmacological blockade of Y1 receptors in transplanted mouse and human islets. Furthermore, treatment of non-obese diabetic mice with a Y1 receptor antagonist delays the onset of diabetes. Mechanistically, Y1 receptor signaling inhibits the production of cAMP in islets, which via CREB mediated pathways results in the down-regulation of several key enzymes in glycolysis and ATP production. Thus, manipulating Y1 receptor signaling in β-cells offers a unique therapeutic opportunity for correcting insulin deficiency as it occurs in the pathological state of type-1 diabetes as well as during islet transplantation.Islet transplantation is considered one of the potential treatments for T1DM but limited islet survival and their impaired function pose limitations to this approach. Here Loh et al. show that the Y1 receptor is expressed in β- cells and inhibition of its signalling, both genetic and pharmacological, improves mouse and human islet function.info:eu-repo/semantics/publishe
Development of UHPLC-MS/MS methods to quantify 25 antihypertensive drugs in serum in a cohort of patients treated for hypertension
We developed three ultra-high pressure liquid chromatography coupled to mass spectrometry detection (UHPLC-MS/MS) methods to quantify 25 antihypertensive drugs in serum samples. Patient-reported drug lists were collected, and drug concentrations were analysed in samples from 547 patients, half with uncontrolled hypertension, and all treated with ≥ 2 antihypertensive drugs.
For sample preparation, serum was mixed with deuterated internal standards and acetonitrile and precipitated. Aliquots of the supernatant were injected on UHPLC-MSMS with a C18 reversed phase column. The mobile phase was 0.1 % HCOOH (formic acid) in water and 0.1 % HCOOH in acetonitrile (except in methanol for spironolactone/canrenone) at a flow rate of 0.4 mL/min. The calibrators and internal controls were prepared in Autonorm™. The calibration ranges were wide, and the models were linear or quadratic with squared correlation coefficients ≥ 0.97. The limits of detection and quantification, specificity, carry-over, and matrix effects were acceptable. The accuracy of the internal controls was in the range 85–121 %, and the intermediate precision for all drugs was 4–28 %.
The patient-reported antihypertensive drug use and the detected serum drug concentrations were in accordance with that most frequently prescribed nationally. The percent non-detectable level was 5–10 % for bendroflumethiazide, doxazosin, nifedipine, and ramipril. Often the drug dose chosen was lower than the recommended maximum daily dose. We report the maximum (Cmax) and minimum (Cmin) drug concentrations after drug intake. The inter-individual pharmacokinetic variability at Cmin was 18-fold for hydrochlorothiazide, 22-fold for losartan carboxyl acid, 26-fold for amlodipine, 44-fold for candesartan, and 50-fold for valsartan.
Our methods are suitable for measuring antihypertensive drugs in patient serum for therapy control.publishedVersio
Extending conceptual understanding : how interprofessional education influences affective domain development
Background:
Interprofessional learning (IPL) can influence affective domain development of students, through teaching activities that facilitate learning with, from and about other professions. Current quantitative evidence offers limited explanation of how this learning is achieved within IPL programmes. This original paper tests a conceptual framework drawn from theories on IPL and affective domain development (attitudes, values and behaviours) to explain what works for whom, when and in what circumstances.
Methods: The objectives of the study were twofold: to evaluate the impact of the IPL programme on the student’s attitudes and values, and identify behaviour changes in clinical practice towards interprofessional working. Using an action research approach, based in practice, an IPL programme was delivered over six weeks. Students from five professional disciplines: nursing, radiography, physiotherapy, social work, and podiatry (n=63) participated over the two action research cycles and in semi structured focus groups (n=37).
Results: The recorded personal experiences of the IPL activities on the students were examined in relation to the: type of activity; impact on the affective domain of learning (attitude, value, or behaviour) and self-reported outcome on application to their practice. Modification in affective domain development was measured to identification or internalisation stage for 30 of the students. Self-reported outcomes on application to practice included direct impact on patient care, personal resilience building, improved communication and ability to challenge practice.
Conclusion: This paper presents a conceptual framework not evident in current research, in regards to what IPL works for whom, in what circumstances and when. IPL Activities that address a personal reward or incentive and are delivered over 4 weeks, imitating ‘circles of care,’ that explore self-assessment, team building and reflection can lead to sustained change in values, attitudes and behaviours.
Keywords: Action Research, Interprofessional Education, Interprofessional learning, Health and Social care, Collaboration
In participatory budgeting we trust? Fairness, tactics and (in)accessibility in participatory governance
Participatory budgeting (PB) is a significant innovation in democracy and local development. PB provides the opportunity for citizens to engage in processes of deliberation and decision-making upon the allocation of public funds. As new critical discourse emerges surrounding this model of local government spending, a significant area warranting investigation concerns how trust, and indeed mistrust, factor into PB. Through an analysis of interviews with residents and Council staff engaged in PB processes in a county in the north of England, we highlight the ways in which issues of trust can impact on participation in these initiatives, and also strengthen relationships between voting delegates, project teams and local government. This paper argues that increasing the perceived accessibility, and reconsidering the inclusion of mass membership groups in PB, might help to create progressive, effective and trustful participation
Gendering the careers of young professionals: some early findings from a longitudinal study. in Organizing/theorizing: developments in organization theory and practice
Wonders whether companies actually have employees best interests at heart across physical, mental and spiritual spheres. Posits that most organizations ignore their workforce – not even, in many cases, describing workers as assets! Describes many studies to back up this claim in theis work based on the 2002 Employment Research Unit Annual Conference, in Cardiff, Wales
Nobel prize for the artemisinin and ivermectin discoveries: a great boost towards elimination of the global infectious diseases of poverty
Regional Heterogeneity and Firms’ Innovation: The Role of Regional Factors in Industrial R&D in India
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