Experimental and numerical investigations on the impact behaviour of pristine and patch-repaired composite laminates.

The present paper investigates the impact behaviour of both pristine carbon-fibre-reinforced-plastic (CFRP) composite laminates and repaired CFRP laminates. For the patch-repaired CFRP specimen, the pristine CFRP panel specimen has been damaged by cutting out a central disc of the CFRP material and then repaired using an adhesively bonded patch of CFRP to cover the hole. Drop-weight, impact tests are performed on these two types of specimens and a numerical elastic-plastic, three-dimensional damage model is developed and employed to simulate the impact behaviour of both types of specimen. This numerical model is meso-scale in nature and assumes that cracks initiate in the CFRP at a nano-scale, in the matrix around fibres, and trigger sub-micrometre intralaminar matrix cracks during the impact event. These localized regions of intralaminar cracking then lead to interlaminar, i.e. delamination, cracking between the neighbouring plies which possess different fibre orientations. These meso-scale, intralaminar and interlaminar, damage processes are modelled using the numerical finite-element analysis model with each individual ply treated as a continuum. Good agreement is found between the results from the experimental studies and the predictions from the numerical simulations. This article is part of the theme issue 'Nanocracks in nature and industry'.

Recruitment and retention of participants in UK surgical trials: survey of key issues reported by trial staff.

BACKGROUND: Recruitment and retention of participants in surgical trials is challenging. Knowledge of the most common and problematic issues will aid future trial design. This study aimed to identify trial staff perspectives on the main issues affecting participant recruitment and retention in UK surgical trials. METHODS: An online survey of UK surgical trial staff was performed. Respondents were asked whether or not they had experienced a range of recruitment and retention issues, and, if yes, how relatively problematic these were (no, mild, moderate or serious problem). RESULTS: The survey was completed by 155 respondents including 60 trial managers, 53 research nurses, 20 trial methodologists and 19 chief investigators. The three most common recruitment issues were: patients preferring one treatment over another (81·5 per cent of respondents); clinicians' time constraints (78·1 per cent); and clinicians preferring one treatment over another (76·8 per cent). Seven recruitment issues were rated moderate or serious problems by a majority of respondents, the most problematic being a lack of eligible patients (60·3 per cent). The three most common retention issues were: participants forgetting to return questionnaires (81·4 per cent); participants found to be ineligible for the trial (74·3 per cent); and long follow-up period (70·7 per cent). The most problematic retention issues, rated moderate or serious by the majority of respondents, were participants forgetting to return questionnaires (56·4 per cent) and insufficient research nurse time/funding (53·6 per cent). CONCLUSION: The survey identified a variety of common recruitment and retention issues, several of which were rated moderate or serious problems by the majority of participating UK surgical trial staff. Mitigation of these problems may help boost recruitment and retention in surgical trials.

ANTECEDENTES: El reclutamiento y la retención de participantes en los ensayos quirúrgicos es un desafío. Conocer los problemas más habituales y conflictivos ayudará al diseño de futuros ensayos. Este estudio tuvo como objetivo identificar la percepción de los participantes sobre cuáles son los principales problemas que afectan el reclutamiento y la retención de participantes en los ensayos quirúrgicos del Reino Unido. MÉTODOS: Encuesta electrónica a profesionales de la salud que habían participado en ensayos quirúrgicos del Reino Unido. Se preguntó a los encuestados si habían experimentado o no algún problema en temas de reclutamiento o retención y, en caso afirmativo, qué tan conflictivos fueron (ningún problema/problema leve/moderado/grave). RESULTADOS: Completaron la encuesta 155 participantes, de los que 60 eran directores del ensayo, 53 enfermeras de investigación, 20 metodólogos de ensayos y 19 investigadores principales. Los tres problemas más comunes en el reclutamiento fueron: pacientes que prefieren un tratamiento sobre otro (81,5% de los encuestados), escaso tiempo de dedicación de los médicos (78,1%) y médicos que prefieren un tratamiento sobre otro (76,8%). La mayoría de los encuestados calificaron siete problemas de reclutamiento como "moderados" o "graves", siendo el más conflictivo la falta de pacientes elegibles (60,3%). Los tres problemas de retención más habituales fueron: participantes que olvidaron devolver los cuestionarios (81,4%), participantes que no fueron elegibles para el ensayo (74,3%) y el largo período de seguimiento (70,7%). Los problemas de retención más conflictivos, calificados como "moderados" o "graves" por la mayoría de los encuestados, fueron el olvido de los participantes para devolver los cuestionarios (56,4%) y el escaso tiempo/financiación para la enfermera investigadora (53,6%). CONCLUSIÓN: La encuesta identificó una serie de problemas habituales en el reclutamiento y la retención de los pacientes, muchos ellos calificados como "moderados" o "graves" por la mayoría del personal involucrado en los ensayos quirúrgicos del Reino Unido. Mitigar estos problemas puede ayudar a impulsar el reclutamiento y la retención en los ensayos quirúrgicos.

Primary Care-Based Health Coaching Intervention for Weight Loss in Overweight/Obese Adults: A 2-Year Experience.

Background: Obesity is a major contributor to medical comorbidity and places a large economic burden on health care. This study examined the effectiveness of primary care-integrated health coaching for weight loss in overweight/obese patients. Participants/Methods: This observational clinical study with a retrospective comparison analysis was performed at an urban academic primary care practice. A total of 271 individuals with a BMI >25 kg/m2 were recruited and followed for 2 years. A standardized health coaching intervention was used to promote weight loss. The main outcome measures were weight loss as a percentage of initial body weight and proportion of patients with weight loss ≥5% initial body weight, controlling for relevant covariates. An activity-based cost assessment of health coaching for weight loss was also performed. Results: Health coaching was associated with a mean loss of 7.24% initial weight after 12 months (95% CI = 8.68 to 5.90) and 6.77% after 24 months (95% CI = 8.78 to 4.76). Coached patients were more likely to achieve ≥5% of initial weight loss at both 12 and 24 months (P < .001). Health coaching costs were $288.54 per participant over 1 year. Conclusions: Primary care-integrated health coaching was associated with statistically significant weight loss in overweight and obese adults.

Implementation of point-of-care testing in a general internal medicine practice: A confirmation study.

BACKGROUND: In a previous study we reported on the impact of point-of-care testing (POCT) on practice efficiency in an academic primary care practice that was established to develop new models of care delivery. Here we report a follow-on confirmation study in a more typical primary care practice in the community. METHODS: In this observational study with a retrospective comparison analysis we measured metrics of practice efficiency on two patient cohorts: those that did not receive POCT and those that did. RESULTS: In the patient cohort that received POCT there was a 99% reduction in letters to patients (p<0.001), a 75% decrease in calls to patients (not significant due to small numbers), a 50% reduction in follow-up tests per visit (p=0.044) and a 38% reduction in follow-up visits due to abnormal test results (p=0.178). Financial analysis including testing costs, revenues and efficiency gains to the practice demonstrated a net financial benefit of $11.90-14.74 per patient visit. CONCLUSIONS: Our data confirm the earlier published findings that POCT can improve metrics of practice efficiency in a primary care practice.

Impact of HbA1c Testing at Point of Care on Diabetes Management.

Diabetes is a highly prevalent disease also implicated in the development of several other serious complications like cardiovascular or renal disease. HbA1c testing is a vital step for effective diabetes management, however, given the low compliance to testing frequency and, commonly, a subsequent delay in the corresponding treatment modification, HbA1c at the point of care (POC) offers an opportunity for improvement of diabetes care. In this review, based on data from 1999 to 2016, we summarize the evidence supporting a further implementation of HbA1c testing at POC, discuss its limitations and propose recommendations for further development.

National Institute of Biomedical Imaging and Bioengineering Point-of-Care Technology Research Network: Advancing Precision Medicine.

To advance the development of point-of-care technology (POCT), the National Institute of Biomedical Imaging and Bioengineering established the POCT Research Network (POCTRN), comprised of Centers that emphasize multidisciplinary partnerships and close facilitation to move technologies from an early stage of development into clinical testing and patient use. This paper describes the POCTRN and the three currently funded Centers as examples of academic-based organizations that support collaborations across disciplines, institutions, and geographic regions to successfully drive innovative solutions from concept to patient care.

Maximizing the Patient-Centered Medical Home (PCMH) by Choosing Words Wisely.

BACKGROUND: Culture is transmitted through language and reflects a group's values, yet much of the current language used to describe the new patient-centered medical home (PCMH) is a carryover from the traditional, physician-centric model of care. This language creates a subtle yet powerful force that can perpetuate the status quo, despite transformation efforts. This article describes new terminology that some innovative primary care practices are using to support the transformational culture of the PCMH. METHODS: Data come from the Agency for Healthcare Research and Quality-funded Working Conference for PCMH Innovation 2013, which convened 10 innovative practices and interdisciplinary content experts to discuss innovative practice redesign. Session and interview transcripts were analyzed using a grounded theory approach to identify patterns and explore their significance. RESULTS: Language innovations are used by 5 practices. Carefully selected terms facilitate creative reimagining of traditional roles and spaces through connotations that highlight practice goals. Participants felt that the language used was important for reinforcing substantive changes. CONCLUSIONS: Reworking well-established vernacular requires openness to change. True transformation does not, however, occur through a simple relabeling of old concepts. New terminology must represent values to which practices genuinely aspire, although caution is advised when using language to support cultural and clinical change.

Affine and nonaffine motions in sheared polydisperse emulsions.

We study dense and highly polydisperse emulsions at droplet volume fractions ϕ≥0.65. We apply oscillatory shear and observe droplet motion using confocal microscopy. The presence of droplets with sizes several times the mean size dramatically changes the motion of smaller droplets. Both affine and nonaffine droplet motions are observed, with the more nonaffine motion exhibited by the smaller droplets which are pushed around by the larger droplets. Droplet motions are correlated over length scales from one to four times the mean droplet diameter, with larger length scales corresponding to higher strain amplitudes (up to strains of about 6%).

Missed opportunities for impact in patient and carer involvement: a mixed methods case study of research priority setting.

PLAIN ENGLISH SUMMARY: Healthcare workers want to listen more to patients and their carers in all sorts of areas of healthcare. This can include choosing topics for medical research. We looked at how patients and carers have helped to choose topics for research about type I diabetes. We aimed to find out if, and why, researchers often rejected their choices. We looked at a project which brought together patients, carers and healthcare workers to choose topics for research about type 1 diabetes. The group first asked patients, carers and healthcare workers to suggest ideas for research questions. But the group had to follow rules about what counted as a good research question. Some people's ideas did not count as good research questions, and they were rejected at the start. We looked at who were most likely to have their ideas rejected at the start. We found that patients and carers were most likely to have a suggestion rejected. Then we looked at the rejected questions in detail. They were mostly about curing diabetes, preventing diabetes and understanding how diabetes works. There were also some questions about access to medicines and the quality of care. Researchers should ask patients and carers for help deciding what counts as a good research question from the start of projects like these. We should also think about what might be getting in the way of patients and carers making more of a difference in research. ABSTRACT: Background Patients and carers are increasingly involved in deciding on topics for medical research. However, so far, it has been difficult to gain an accurate picture of the impact of such involvement because of poor reporting and evaluation in published studies to date. This study aimed to explore how a partnership of patients, carers, healthcare professionals and organisations identified questions for future research and why patients and carers had a limited impact on this process. Methods In the first stage of the partnership process, relevant service users and providers (including patients, carers, healthcare professionals and voluntary organisations) were invited to submit suggested research questions about the treatment of type 1 diabetes, via a national online and paper survey. The partnership followed formal protocols that defined a researchable question. This meant that many respondents' suggested research questions were rejected at the start of the process. We analysed survey submissions to find out which groups of respondents were most likely to have their suggestions rejected and what these suggestions were about. Results Five hundred eighty-three respondents submitted 1143 suggested research questions, of which 249 (21.8 %) were rejected at the first stage. Respondents with lived experience of this long-term condition (patients and carers) were more likely than those without lived experience to submit a research question that would be rejected (35.6 vs. 16.5 %; p < 0.0005). Among the rejected questions submitted by patients and carers, there were several key themes: questions about cure, cause and prevention, understanding the disease, healthcare policy and economics. Conclusions In this case study, early decisions about what constituted a researchable question restricted patients' and carers' contributions to priority setting. When discussions about a project's remit take place before service users are involved, researchers risk distorting the potential impact of involvement. Impact assessments should consider not only the differences patients and carers make to research but also the differences they could have made in the absence of systemic barriers. We recommend that initiatives aimed at involving patients and carers in identifying research questions involve them as early as possible, including in decisions about how and why suggested research questions are selected or rejected.

Implementation of point-of-care testing in an ambulatory practice of an academic medical center.

OBJECTIVES: Point-of-care laboratory testing (POCT) offers reduced turnaround time and may promote improved operational efficiency. Few studies have been reported that document improvements from implementing POCT in primary care. METHODS: We measured metrics of practice efficiency in a primary care practice before and after implementation of POCT, including the total number of tests ordered, letters and phone calls to patients, and revisits due to abnormal test results. We performed a cost and revenue analysis. RESULTS: Following implementation of POCT, there was a 21% decrease in tests ordered per patient (P < .0001); a decrease in follow-up phone calls and letters by 89% and 85%, respectively (P < .0001 and P < .0001); and a 61% decrease in patient revisits (P = .0002). Estimated testing revenues exceeded expenses by $6.62 per patient, and potential cost savings from improved efficiency were $24.64 per patient. CONCLUSIONS: POCT can significantly improve clinical operations with cost reductions through improved practice efficiency.

Coexistence of cluster spin glass and superconductivity in Ba(Fe(1-x)Co(x))2As2 for 0.060≤x≤0.071.

We present 75As nuclear magnetic resonance data from measurements of a series of Ba(Fe(1-x)Co(x))2As2 crystals with 0.00≤x≤0.075 that reveals the coexistence of frozen antiferromagnetic domains and superconductivity for 0.060≤x≤0.071. Although bulk probes reveal no long range antiferromagnetic order beyond x=0.06, we find that the local spin dynamics reveal no qualitative change across this transition. The characteristic domain sizes vary by more than an order of magnitude, reaching a maximum variation at x=0.06. This inhomogeneous glassy dynamics may be an intrinsic response to the competition between superconductivity and antiferromagnetism in this system.

Response of the µ-opioid system to social rejection and acceptance.

The endogenous opioid system, which alleviates physical pain, is also known to regulate social distress and reward in animal models. To test this hypothesis in humans (n=18), we used an µ-opioid receptor (MOR) radiotracer to measure changes in MOR availability in vivo with positron emission tomography during social rejection (not being liked by others) and acceptance (being liked by others). Social rejection significantly activated the MOR system (i.e., reduced receptor availability relative to baseline) in the ventral striatum, amygdala, midline thalamus and periaqueductal gray (PAG). This pattern of activation is consistent with the hypothesis that the endogenous opioids have a role in reducing the experience of social pain. Greater trait resiliency was positively correlated with MOR activation during rejection in the amygdala, PAG and subgenual anterior cingulate cortex (sgACC), suggesting that MOR activation in these areas is protective or adaptive. In addition, MOR activation in the pregenual ACC was correlated with reduced negative affect during rejection. In contrast, social acceptance resulted in MOR activation in the amygdala and anterior insula, and MOR deactivation in the midline thalamus and sgACC. In the left ventral striatum, MOR activation during acceptance predicted a greater desire for social interaction, suggesting a role for the MOR system in social reward. The ventral striatum, amygdala, midline thalamus, PAG, anterior insula and ACC are rich in MORs and comprise a pathway by which social cues may influence mood and motivation. MOR regulation of this pathway may preserve and promote emotional well being in the social environment.

Telephone follow-up as a primary care intervention for postdischarge outcomes improvement: a systematic review.

OBJECTIVE: Postdischarge telephone follow-up plays an integral part in transitional care efforts in many regions. We systematically reviewed the literature to evaluate the evidence regarding the impact of primary care-based telephone follow-up on postdischarge emergency department visits and hospital readmissions. METHODS: We performed an electronic database search for relevant telephone follow-up studies originating in adult primary care settings. RESULTS: Only 3 studies (N=1765) met entry criteria for this review. None of the studies demonstrated evidence of reduced admissions or emergency department visits from primary care-based telephone follow-ups. All 3 studies reported improved primary care office contact as a result of telephone follow-up intervention. CONCLUSIONS: Despite the growing use of primary care-based telephone follow-up in the postdischarge period, there are no high-quality studies demonstrating its benefit. However, its positive impact on patient engagement holds potentially meaningful implications. In light of recent national health care legislation, the primary care field is ripe for high-quality studies to evaluate the effectiveness of telephone follow-up for patients in the postdischarge period. Particular areas of research focus are discussed.

The presence of radiological features on chest radiographs: how well do clinicians agree?

AIM: To compare levels of agreement amongst paediatric clinicians with those amongst consultant paediatric radiologists when interpreting chest radiographs (CXRs). MATERIALS AND METHODS: Four paediatric radiologists used picture archiving and communication system (PACS) workstations to evaluate the presence of five radiological features of infection, independently in each of 30 CXRs. The radiographs were obtained over 1 year (2008) from children with fever and signs of respiratory distress, aged 6 months to <16 years. The same CXRs were interpreted a second time by the paediatric radiologists and by 21 clinicians with varying experience levels, using the Web 1000 viewing system and a projector. Intra- and interobserver agreement within groups, split by grade and specialty, were analysed using free-marginal multi-rater kappa. RESULTS: Normal CXRs were identified consistently amongst all 25 participants. The four paediatric radiologists showed high levels of intraobserver agreement between methods (kappa scores between 0.53 and 1.00) and interobserver agreement for each method (kappa scores between 0.67 and 0.96 for PACS assessment). The 21 clinicians showed varying levels of agreement from 0.21 to 0.89. CONCLUSION: Paediatric radiologists showed high levels of agreement for all features. In general, the clinicians had lower levels of agreement than the radiologists. This study highlights the need for improved training in interpreting CXRs for clinicians and the timely reporting of CXRs by radiologists to allow appropriate patient management.

Mumps outbreak on the island of Anglesey, North Wales, December 2008-January 2009.

Twenty-three cases of clinical mumps in young people have been reported in North Wales over a five-week period since late December 2008. All cases have social links, and most of them have received two doses of mumps-containing vaccine.

In vitro effect of cyclosporin A on primary and chronic BK polyoma virus infection in Vero E6 cells.

Cyclosporin A (CsA) is known to possess antiviral activity against several viruses in vitro, but the effect of CsA on BK polyoma virus (BKV) replication has not been examined. We investigated the impact of CsA on primary, chronic, and high-level BKV infection using a cell system of kidney cell origin (Vero E6 cells). During the first 2 h post infection, cells treated with CsA up to 3200 microg/L showed a near-identical BK viral load to untreated cells, with only a very minor reduction in the CsA-treated cells observed at 4 h. In chronic culture, CsA completely suppressed the primary BKV infection peak in a non-dose-dependent manner within the dose range of 200-12,800 microg/L (P<0.05). BKV reactivation was also inhibited in the presence of CsA at doses of 200-3200 microg/L: the mean number of BKV DNA copies/mL remained stable or even decreased slightly compared with a 7-log increase in the non-CsA group (P<0.01). CsA did not influence BKV DNA copies/mL in Vero E6 cells with high-level infection (>10(9) copies/mL). Cellular protein measurements indicated that the antiviral effect of CsA was not a result of cytotoxicity. These findings from a relevant in vitro kidney cell system indicate that CsA suppresses the primary BKV infection peak and inhibits escape to BKV reactivation; these effects are dose independent and not related to cytotoxicity. The intracellular antiviral mode of action of CsA against BKV does not appear to be via inhibition of viral cell entry pathways.

Carnitine, acylcarnitine and amino acid profiles analyzed by tandem mass spectrometry in a surfactant/virus mouse model of acute hepatic encephalopathy.

Tandem mass spectrometry (MS/MS) was used to analyze multiple serum metabolites for the first time in a surfactant/virus mouse model of acute hepatic encephalopathy (AHE). AHE is characterized by acute liver failure that can lead to potentially lethal increases in intracranial pressure. We have reproduced AHE in young CD-1 mice exposed from postnatal day (P) 2-13 to the industrial surfactant, Toximul 3409F (Tox), and then infected intranasally on P14 with sublethal doses (LD(10-30)) of mouse-adapted human influenza B (Lee) virus (FluB). The sera analyzed by MS/MS were from mice exhibiting typical markers of Tox-mediated potentiation of viral illness, including reduced weights and blood glucose levels. Most metabolite abnormalities were not evident until five days after viral infection (P19), the time corresponding to the onset of weight loss and mortality. Values for fatty acylcarnitines and amino acids in the Tox+FluB-treated mice were either additive or supra-additive relative to the effects of either treatment alone. Amino acid profiles were consistent with those reported for human AHE. None of the treated mice exhibited signs of carnitine deficiency, and propionylcarnitine levels were normal. On P19, mice given combined Tox+FluB treatment had significant increases in levels of both medium- and long-chain acylcarnitines (C6:0-C12:0 and C14:0-C20:0, respectively), including their monounsaturated metabolites. Levels of medium-chain dicarboxylic and long-chain hydroxy-acylcarnitines were also elevated in the combined treatment group. The results of this study indicate a diffuse mitochondrial dysfunction in Tox+FluB-treated mice that results in a serum metabolite profile unique from those observed in classic inherited metabolic disorders.

Utilization of vero cells for primary and chronic BK virus infection.

BK virus (BKV) nephropathy has a poor prognosis for renal allograft survival with 30% to 60% risk of allograft loss over 1 year. In the past decade, BKV nephropathy has occurred in 1% to 10% of renal transplant patients, with higher rates observed in patients with increased immunosuppression exposure and renal allograft injury. Vero cells (Green monkey kidney cell origin) were optimized for BKV primary and chronic infection inclusive of culture requirements for 60-day growth and monolayer confluence. Quantification of BKV replication in the culture supernatant (SN) and cells was by real-time polymerase-chain reaction (PCR) using the Roche Lightcycler 2.0. Primary BKV infection of Vero cells is achieved by 2 hour incubation with 6.5 x 10(5) BKV copies with subsequent washing of cells leading to steady-state cellular infection of 10(2) to 10(3) BKV copies. Primary infection is demonstrated within 7 to 10 days by a >10-fold increase of BKV copies in SN. Thereafter, a BKV viral load reduction in SN to a chronic/latent level (<10(2) BKV copies in SN) is observed by 14 days. Vero cells with chronic low-level BKV infection (10(2)-10(3) BKV copies in cells) exhibited reactivation (>10(5) BKV copies in SN) in >72% of late culture wells after 40 days. Vero cells can accommodate primary and chronic BKV infection followed by viral reactivation in late culture. The performance characteristics of 3 different pathogenic BKV strains obtained from patients with BKV nephropathy had infectivity profiles that correlated well the relative clinical profile in this Vero cell culture system.

Evaluation of performance factors affecting two formulations of cyclosporine in pediatric renal transplant patients.

Success of renal transplantation in children is largely due to improvements in immunosuppressant therapy since the introduction of calcineurin inhibitors. The aim of this study was to identify possible factors that result in formulation differences in the exposure of pediatric patients to cyclosporine (CsA). We examined the handling of the two major formulations of CsA in a group of pediatric renal transplant recipients. The pharmacokinetic profiles of both formulations were assessed, and the data stratified to assess the effects of age, gender, time posttransplant, and other concomitant drug therapy on the two CsA formulations. The microemulsified formulation (MEC) enhanced bioavailability compared to the older oil-based formulation (CYA), especially at C2, with more predictable and consistent absorption in children. This higher bioavailability allowed a 15% reduction of dosing to achieve equal drug exposure. The concentration achieved by MEC at C2 demonstrated a much higher correlation with area under the concentration curve (AUC) than the concentration at C0. In the case of CYA a strong correlation was obtained between AUC and the concentrations obtained at both C0 and C2. Calcium channel blockers increased AUC(0-8) for both CsA formulations. Norfloxacin and pravastatin cotreatment had no effect on either of the CsA formulations. In contrast, the bioavailability of CsA was increased in boys using MEC formulation but this gender-based difference was absent during the use of CYA. This suggests that caution is required for introduction of new formulations of drugs to pediatric patients to evaluate differential effects of age, gender, and concomitant drug therapy.