Temperature and strain rate effects on the mechanical properties of a polymer-bonded explosive

Abstract: The aim of the research reported here was to investigate the strain rate and temperature sensitivity of Rowanex 1100 Type 1A, a polymer-bonded explosive (PBX). The stress supported by this PBX at high rates of deformation (1750 ± 225 s−1) was found to be about an order of magnitude greater than that supported at low rates (0.015 s−1). Temperature was also found to have a large effect, with the strength of the material decreasing exponentially with temperature over the range studied (–60 to +60 °C). The exponents for the decay of the PBX’s strength with temperature at both low and high strain rates were the same within experimental error. So a temperature/strain rate shift factor could be determined and was found to be 31.2 ± 2.4 K/decade of strain rate

Robust Inference of Trees

This paper is concerned with the reliable inference of optimal tree-approximations to the dependency structure of an unknown distribution generating data. The traditional approach to the problem measures the dependency strength between random variables by the index called mutual information. In this paper reliability is achieved by Walley's imprecise Dirichlet model, which generalizes Bayesian learning with Dirichlet priors. Adopting the imprecise Dirichlet model results in posterior interval expectation for mutual information, and in a set of plausible trees consistent with the data. Reliable inference about the actual tree is achieved by focusing on the substructure common to all the plausible trees. We develop an exact algorithm that infers the substructure in time O(m^4), m being the number of random variables. The new algorithm is applied to a set of data sampled from a known distribution. The method is shown to reliably infer edges of the actual tree even when the data are very scarce, unlike the traditional approach. Finally, we provide lower and upper credibility limits for mutual information under the imprecise Dirichlet model. These enable the previous developments to be extended to a full inferential method for trees.Comment: 26 pages, 7 figure

Patterns of antihypertensive prescribing, discontinuation and switching among a Hong Kong Chinese population from over one million prescriptions

Hypertension is an alarming public health problem among Chinese. The present study evaluated the prescribing patterns, discontinuation and switching profiles of antihypertensive agents and their associated factors in one Hong Kong Chinese population. Data were retrieved from computerized records for patients prescribed anti-hypertensive agents in government primary care clinics of Hong Kong from January, 2004 to June, 2007. A total of 1,069,836 antihypertensive drug visits, representing 67,028 patients, were analyzed. The most commonly prescribed drugs were Calcium Channel Blockers (CCBs) (49%), b-Blockers (BBs) (46%) and Angiotensin-Converting Enzyme Inhibitors (ACEIs) (19%). Thiazide diuretic prescribing was low (13%) and on the decline (14% in 2004 to 12% in 2007). Prescribing of ACEIs was rising (16% in 2004 to 23% in 2007). Patients’ age, gender, and socio-economic status were independent predictors of class of anti-hypertensive prescribed but explained less than 3.5% of the variation observed. Drug discontinuation was highest for BBs (21%) and lowest for CCBs (12%). The high rates of discontinuation in BBs remained apparent after controlling for confounding variables. Switching was less common than discontinuation and was most likely with thiazide diuretics. To summarize, prescribing of CCBs and BBs were high and that of thiazide diuretics particularly low in this Chinese population when compared with international trends. CCBs may be a particularly favorable antihypertensive treatment in Chinese, given the high discontinuation rates of BBs and international guidelines advising against the use of BBs as first-line therapy. The low use of thiazide diuretics warrants further clinical and cost effectiveness studies among Chinese

Characterisation of the impact response of energetic materials: Observation of a low-level reaction in 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105)

Time resolved and integrated diagnostics including high speed photography, mass and optical spectroscopy, and optical-radiometry used to study impact response of high explosives in far more detail than possible with conventional sensitiveness tests.The authors wish to acknowledge the funding and provision of samples for this research by AWE plc.This is the author accepted manuscript. The final version is available from the Royal Society of Chemistry via http://dx.doi.org/10.1039/C6RA03096

Bean quest 2002: the final frontier

Non-Peer ReviewedThe agronomic, economic and genetic pieces of the jigsaw puzzle for developing a dryland bean industry in Saskatchewan are coming together. In 2002, dryland bean growers in Southeastern Saskatchewan made a profit using new varieties of black and pinto bean. Much of the credit for this goes to the hard work, homework, and perseverance of the crop clubs that have developed around the province in the past few years. The research and development effort of the past 10 years is finally starting to pay dividends in the dry bean sector of the pulse industry. In this paper, we would like to briefly summarize some of the key results of various dry bean research and development projects that have been underway in the past few years

Strong laws of large numbers for sub-linear expectations

We investigate three kinds of strong laws of large numbers for capacities with a new notion of independently and identically distributed (IID) random variables for sub-linear expectations initiated by Peng. It turns out that these theorems are natural and fairly neat extensions of the classical Kolmogorov's strong law of large numbers to the case where probability measures are no longer additive. An important feature of these strong laws of large numbers is to provide a frequentist perspective on capacities.Comment: 10 page

Delivering integrated child development care in Pakistan: protocol for a clustered randomised trial

Background: Early childhood developmental delay is associated with significant disadvantage in adult life. In Pakistan, high prevalence of developmental delay is associated with poverty, under-nutrition, and maternal depression. Aim: To assess the effectiveness of an early child development counselling intervention delivered at private GP clinics, in poor urban communities. Design & setting: A clustered randomised trial in Pakistan. Method: The intervention was developed following a period of formative research, and in consultation with local experts. A total of 2112 mother–child pairs will be recruited at 32 clinics, from within the locality (cluster); 16 clinics per arm. A primary care counselling intervention (promoting child development, nutrition, and maternal mental health) will be delivered at 6 weeks, 3, 6, and 9 months of the child’s age. Monitoring, assessment, and treatment will also be performed at quarterly visits in intervention clinics. Primary outcome is the developmental delay at 12 months (ASQ-3 scores). Secondary outcomes are stunting rate, and maternal depression (PHQ-9 score). In addition, a process evaluation and costing study will be conducted. Discussion: This trial will be the first to assess an early child development intervention, delivered in private GP clinics for poor urban communities in Pakistan. If found to be effective, this public–private model may offer a more sustainable, and feasible option for populations in poor urban settings, where private GP clinics are the most accessible provider of primary health care. There is scope for scale-up at provincial level, should the intervention be effective. Trial registration: The trial has been registered with the Current Controlled Trials ISRCTN48032200

Infection control in a developing world.

The global HIV and tuberculosis (TB) epidemics have placed enormous burdens upon already overstretched healthcare workers and poorly resourced healthcare facilities in sub-Saharan Africa. The rapid emergence of multi-drug resistant TB, and its association with hospital-based outbreaks, have highlighted the role that healthcare facilities inadvertently may play in maintaining TB transmission, and the vital importance of attaining good TB infection control. James Elston, a specialist physician in infectious diseases and general internal medicine, who recently returned from a second stint in Swaziland, says many of the region's healthcare facilities are outdated, poorly ventilated, and were not designed for their current purpose. Here he describes how U.K.-based architects and healthcare engineers responded to an urgent call for assistance and, via close collaboration, and using novel design software, empowered healthcare workers to dramatically and rapidly improve their TB inpatient facilities, and protect the health of patients and staff

Adapting and implementing training, guidelines and treatment cards to improve primary care-based hypertension and diabetes management in a fragile context: results of a feasibility study in Sierra Leone

Background Sierra Leone, a fragile country, is facing an increasingly significant burden of non-communicable diseases (NCDs). Facilitated by an international partnership, a project was developed to adapt and pilot desktop guidelines and other clinical support tools to strengthen primary care-based hypertension and diabetes diagnosis and management in Bombali district, Sierra Leone between 2018 and 2019. This study assesses the feasibility of the project through analysis of the processes of intervention adaptation and development, delivery of training and implementation of a care improvement package and preliminary outcomes of the intervention. Methods A mixed-method approach was used for the assessment, including 51 semi-structured interviews, review of routine treatment cards (retrieved for newly registered hypertensive and diabetic patients from June 2018 to March 2019 followed up for three months) and mentoring data, and observation of training. Thematic analysis was used for qualitative data and descriptive trend analysis and t-test was used for quantitative data, wherever appropriate. Results A Technical Working Group, established at district and national level, helped to adapt and develop the context-specific desktop guidelines for clinical management and lifestyle interventions and associated training curriculum and modules for community health officers (CHOs). Following a four-day training of CHOs, focusing on communication skills, diagnosis and management of hypertension and diabetes, and thanks to a CHO-based mentorship strategy, there was observed improvement of NCD knowledge and care processes regarding diagnosis, treatment, lifestyle education and follow up. The intervention significantly improved the average diastolic blood pressure of hypertensive patients (n = 50) three months into treatment (98 mmHg at baseline vs. 86 mmHg in Month 3, P = 0.001). However, health systems barriers typical of fragile settings, such as cost of transport and medication for patients and lack of supply of medications and treatment equipment in facilities, hindered the optimal delivery of care for hypertensive and diabetic patients. Conclusion Our study suggests the potential feasibility of this approach to strengthening primary care delivery of NCDs in fragile contexts. However, the approach needs to be built into routine supervision and pre-service training to be sustained. Key barriers in the health system and at community level also need to be addressed

Orienting Patients to Greater Opioid Safety: Models of Community Pharmacy-Based Naloxone

The leading cause of adult injury death in the USA is drug overdose, the majority of which involves prescription opioid medications. Outside of the USA, deaths by drug overdose are also on the rise, and overdose is a leading cause of death for drug users. Reducing overdose risk while maintaining access to prescription opioids when medically indicated requires careful consideration of how opioids are prescribed and dispensed, how patients use them, how they interact with other medications, and how they are safely stored. Pharmacists, highly trained professionals expert at detecting and managing medication errors and drug-drug interactions, safe dispensing, and patient counseling, are an under-utilized asset in addressing overdose in the US and globally. Pharmacies provide a high-yield setting where patient and caregiver customers can access naloxone—an opioid antagonist that reverses opioid overdose—and overdose prevention counseling. This case study briefly describes and provides two US state-specific examples of innovative policy models of pharmacy-based naloxone, implemented to reduce overdose events and improve opioid safety: Collaborative Pharmacy Practice Agreements and Pharmacy Standing Orders