Pharmacological activation of PDC flux reverses lipid-induced inhibition of insulin action in muscle during recovery from exercise.

Insulin resistance is a risk factor for type 2 diabetes and exercise can improve insulin sensitivity. However, following exercise high circulating fatty acid (FA) levels might counteract this. We hypothesized that such inhibition would be reduced by forcibly increasing carbohydrate oxidation through pharmacological activation of the pyruvate dehydrogenase complex (PDC). Insulin-stimulated glucose uptake was examined with a cross-over design in healthy young men (n = 8) in a previously exercised and a rested leg during a hyperinsulinemiceuglycemic clamp five hours after one-legged exercise with: 1) infusion of saline, 2) infusion of intralipid imitating circulating FA levels during recovery from whole-body exercise, and 3) infusion of intralipid + oral PDC-activator, dichloroacetate (DCA). Intralipid infusion reduced insulin-stimulated glucose uptake by 19% in the previously exercised leg, which was not observed in the contralateral rested leg. Interestingly, this effect of intralipid in the exercised leg was abolished by DCA, which increased muscle PDC activity (130%) and flux (acetylcarnitine 130%) and decreased inhibitory phosphorylation of PDC on Ser293 (∼40%) and Ser300 (∼80%). Novel insight is provided into the regulatory interaction between glucose and lipid metabolism during exercise recovery. Coupling exercise and PDC flux activation upregulated the capacity for both glucose transport (exercise) and oxidation (DCA), which seems necessary to fully stimulate insulin-stimulated glucose uptake during recovery.

Towards space-deployable laser stabilization systems based on vibration-insensitive cubic cavities with crystalline coatings.

We present the development of a transportable laser frequency stabilization system with application to both optical clocks and a next-generation gravity mission (NGGM) in space. This effort leverages a 5-cm long cubic cavity with crystalline coatings operating at room temperature and with a center wavelength of 1064 nm. The cavity is integrated in a custom vacuum chamber with dedicated low-noise locking electronics. Our vacuum-mounted cavity and control system are well suited for space applications, exhibiting state-of-the-art noise performance while being resilient to radiation exposure, vibration, shock, and temperature variations. Furthermore, we demonstrate a robust means of automatically (re)locking the laser to the cavity when resonance is lost. We show that the mounted cavity is capable of reaching technology readiness level (TRL) 6, paving the way for high-performance ultrastable laser systems and eventually optical atomic clocks amenable to future satellite platforms.

Patient and healthcare professionals' perceptions of a combined blood and faecal immunochemical test for excluding colorectal cancer diagnosis in primary care.

OBJECTIVES: To explore the perceptions of patients and healthcare professionals on Raman-faecal immunochemical test (FIT) as an alternative test for colorectal cancer exclusion in primary care. DESIGN: Semi-structured interviews within a feasibility study. SETTING: Patients presenting to primary care with colorectal symptoms and healthcare professionals working in primary and secondary care. PARTICIPANTS: A total of 23 patients and 12 healthcare professionals. METHODS: Patient participants were asked to complete a novel combined Raman-FIT test before being seen in secondary care. This study sought their opinions about the test. We also sought the views of healthcare professionals. FINDINGS: Patients and healthcare professionals agreed that Raman-FIT was a suitable test to be given in primary care. It aligned with routine practice and was a simple test for most patients to complete. CONCLUSIONS: Patients are willing and able to complete the Raman-FIT test in primary care. Raman-FIT may accelerate access to diagnosis with the potential to improve cancer outcomes. PATIENT AND PUBLIC INVOLVEMENT: Lay members (J. H. and I. H.) with experience and knowledge of colorectal cancer and screening contributed to developing, undertaking, and disseminating all aspects of the research. They were supported to collaborate as equal members of the research team. They were involved in developing the study as coapplicants, using personal experience to ensure that the research and its methods were relevant to the patient and public needs. Both prepared participant information sheets, coanalysed data, and contributed to study reporting and dissemination through papers, conference presentations and a lay summary.

A new and versatile template towards vertically oriented nanopillars and nanotubes.

Vertically oriented nanostructures bring unparalleled high surface area, light trapping capability, and high device density to electronic, optoelectronic, and energy storage devices. However, general methods to prepare such structures remain sparse and are typically based on anodized metal oxide templates. Here, we demonstrate a new approach: using vertically oriented tetraaniline nanopillar arrays as templates for creating nanopillars and nanotubes of other materials. The tetraaniline templates are scalable and easy to prepare. Vertical arrays of a variety of materials can be created by directly coating them onto the tetraaniline nanopillars via vapor, solution, or electrodeposition. Since the tetraaniline template is encased within the target material, it does not require post-deposition removal, thus enabling vertical structure formation of sensitive materials. Conversely, removal of the encased tetraaniline template provides vertically oriented nanotube arrays in a lost-wax-type operation. The resulting vertical structures exhibit a high degree of orientation and height uniformity, with tunable feature size, spacing, and array density. Furthermore, the deposition location and shape of the vertical arrays can be patterned at a resolution of 3 µm. Collectively, these attributes should broaden the material repertoire for vertically oriented structures, and lead to advancements in energy storage, electronics, and optoelectronics.

Deformation Rate-Adaptive Conducting Polymers and Composites.

Materials are more easily damaged during accidents that involve rapid deformation. Here, a design strategy is described for electronic materials comprised of conducting polymers that defies this orthodox property, making their extensibility and toughness dynamically adaptive to deformation rates. This counterintuitive property is achieved through a morphology of interconnected nanoscopic core-shell micelles, where the chemical interactions are stronger within the shells than the cores. As a result, the interlinked shells retain material integrity under strain, while the rate of dissociation of the cores controls the extent of micelle elongation, which is a process that adapts to deformation rates. A prototype based on polyaniline shows a 7.5-fold increase in ultimate elongation and a 163-fold increase in toughness when deformed at increasing rates from 2.5 to 10 000% min-1 . This concept can be generalized to other conducting polymers and highly conductive composites to create "self-protective" soft electronic materials with enhanced durability under dynamic movement or deformation.

Oligoaniline-assisted self-assembly of polyaniline crystals.

The conductivity and charge transport mobility of conjugated polymers (CPs) are largely correlated with their degree of crystallinity, rendering the crystallization of CPs an important endeavour. However, such tasks can be challenging, especially in the absence of sidechain functionalization. In this study, we demonstrate that the incorporation of a small amount of oligomers, specifically tetraaniline, can induce crystallization of the parent polymer, polyaniline, through a single-step self-assembly process. The resulting crystals are compositionally homogeneous because the oligomers and their parent polymer share the same repeating unit and are both electroactive. Mechanistic studies reveal that the tetraaniline forms a crystalline seed that subsequently guides the assembly of polyaniline due to their structural similarities. Applying this oligomer-assisted crystallization approach to polyaniline with defined molecular weights resulted in single crystalline nanowires for 5000 Da polyaniline, and nanowires with strong preferential chain orientation for those with molecular weights between 10 000 and 100 000 Da. Absorption studies reveal that the polymer chains are in an expanded conformation, which likely contributed to the high degree of packing order. Two-probe, single nanowire measurements show that the crystals have conductivity as high as 19.5 S cm-1. This method is simple, general, and can potentially be applied to other CPs.

A novel blood based triage test for colorectal cancer in primary care: a pilot study.

BACKGROUND: The majority of colorectal cancers (CRCs) are detected after symptomatic presentation to primary care. Given the shared symptoms of CRC and benign disorders, it is challenging to manage the risk of missed diagnosis. Colonoscopy resources cannot keep pace with increasing demand. There is a pressing need for access to simple triage tools in primary care to help prioritise patients for referral. AIM: To evaluate the performance of a novel spectroscopy-based CRC blood test in primary care. DESIGN & SETTING: Mixed-methods pilot study of test performance and GP focus group discussions in South Wales. METHOD: Patients on the urgent suspected cancer (USC) pathway were recruited for the Raman spectroscopy (RS) test coupled to machine learning classification ('Raman-CRC') to identify CRC within the referred population. Qualitative focus group work evaluated the acceptability of the test in primary care by thematic analysis of focus group theorising. RESULTS: A total of 532 patients aged ≥50 years referred on the USC pathway were recruited from 27 GP practices. Twenty-nine patients (5.0%) were diagnosed with CRC. Raman-CRC identified CRC with sensitivity 95.7%, specificity 69.3% with area under curve (AUC) of 0.80 compared with colonoscopy as the reference test (248 patients). Stage I and II cancers were detected with 78.6% sensitivity. Focus group themes underlined the convenience of a blood test for the patient and the test's value as a risk assessment tool in primary care. CONCLUSION: The findings support this novel, non-invasive, blood-based method to prioritise those patients most likely to have CRC. Raman-CRC may accelerate access to diagnosis with potential to improve cancer outcomes.

Limits of prenatal care coordination for improving birth outcomes among Medicaid participants.

Maternity Care Homes (MCHs) intend to address clinical and psychosocial needs for perinatal patients and are commonly implemented for Medicaid beneficiaries. Rigorous evidence supporting MCHs' effectiveness for improving birth outcomes is thin, but most studies consider only clinical and demographic factors from administrative data. To assess birth outcomes with controls for psychosocial variables known to affect them, this paper considers quantitative participant-level data from the Strong Start for Mothers and Newborns prenatal care initiative, with qualitative case study data to further contextualize results. From 2013 to 2017, Strong Start served over 45,000 Medicaid beneficiaries in 32 states, D.C., and Puerto Rico though MCHs, group prenatal care, or freestanding birth centers. Participant data included risks screens for food insecurity, depression, anxiety, pregnancy intention, and intimate partner violence, in addition to clinical and demographic information. After clinical, demographic and psychosocial risks were controlled in a regression model, Strong Start birth center participants showed significantly lower rates of preterm birth, low birthweight, and cesarean section relative to MCH participants (p < .01). In group prenatal care, White participants showed lower rates of preterm birth (p < .01) and Black participants showed lower rates of low birthweight (p < .05) relative to MCH participants. Strong Start participants reported appreciation for MCH care managers' support, but community and clinical referrals often had long waiting lists or were inaccessible. Transformative care models focusing on provider continuity, relationship building, and patient activation may offer more promise for improving birth outcomes than supplementing medical models with care management and other resources.

Novel Mobile Phase to Control Charge States and Metal Adducts in the LC/MS for mRNA Characterization Assays.

Mass spectrometry is a widely used tool in the characterization of oligonucleotides. This analysis can be challenging due to the large number of possible charge states of oligonucleotides, which can limit the sensitivity of the assay, along with the propensity of oligonucleotides to readily form adducts with free alkali metals. To reduce the adduct formation, oligonucleotides are typically purified with desalting columns prior to analysis. We have developed a mobile phase that gives superior reduction in charge states and adduct formation compared to previously reported methods and, more importantly, obviates the requirement of desalting samples prior to mass spectrometric analysis, significantly decreasing the sample preparation time and amount of RNA required for analysis. We have applied this mobile phase to develop methods to quantify the 5'-capping efficiency and to characterize the polyadenosine (poly(A)) tail of mRNA synthesized in vitro: two critical quality attributes of mRNA therapeutics. Through this, we were able to demonstrate RNA that was co-transcriptionally capped to have capping efficiency equivalent (the percent total molecules that contain a cap) to other reports in the literature using materials that were generated using the same synthesis procedure. Furthermore, by using a mobile phase mixture comprised of hexafluoroisopropanol, triethylammonium acetate, triethylamine, and ethanol, we were able to determine the size distribution of the poly(A) tail in various mRNA samples from DNA templates that ranged from 50 to 150 nt poly(A) and verify that distribution with commercially available RNA standards, successfully demonstrating that this mobile phase composition could be used for characterization assays for both mRNA caps and tails.

Measuring intraoperative surgical instrument use with radio-frequency identification.

OBJECTIVE: Surgical instrument oversupply drives cost, confusion, and workload in the operating room. With an estimated 78%-87% of instruments being unused, many health systems have recognized the need for supply refinement. By manually recording instrument use and tasking surgeons to review instrument trays, previous quality improvement initiatives have achieved an average 52% reduction in supply. While demonstrating the degree of instrument oversupply, previous methods for identifying required instruments are qualitative, expensive, lack scalability and sustainability, and are prone to human error. In this work, we aim to develop and evaluate an automated system for measuring surgical instrument use. MATERIALS AND METHODS: We present the first system to our knowledge that automates the collection of real-time instrument use data with radio-frequency identification (RFID). Over 15 breast surgeries, 10 carpometacarpal (CMC) arthroplasties, and 4 craniotomies, instrument use was tracked by both a trained observer manually recording instrument use and the RFID system. RESULTS: The average Cohen's Kappa agreement between the system and the observer was 0.81 (near perfect agreement), and the system enabled a supply reduction of 50.8% in breast and orthopedic surgery. Over 10 monitored breast surgeries and 1 CMC arthroplasty with reduced trays, no eliminated instruments were requested, and both trays continue to be used as the supplied standard. Setup time in breast surgery decreased from 23 min to 17 min with the reduced supply. CONCLUSION: The RFID system presented herein achieves a novel data stream that enables accurate instrument supply optimization.

Addressing Surgical Instrument Oversupply: A Focused Literature Review and Case-Study in Orthopedic Hand Surgery.

BACKGROUND: Instrument oversupply drives cost in the operating room (OR). We review previously reported methodologies for surgical instrument reduction and report a pilot methodology for optimizing instrument supply via ethnographic instrument tracking of thumb carpometacarpal (CMC) arthroplasties. Additionally, we report a cost analysis of instrument oversupply and potential savings of tray optimization methods. METHODS: Instrument utilization was tracked over 8 CMC arthroplasties conducted by 2 surgeons at an ambulatory surgery center of a large academic hospital. An optimized supply methodology was designed. A cost analysis was conducted using health-system-specific data and previously published research. RESULTS: After tracking instrument use in 8 CMC arthroplasties, a cumulative total of 59 out of the 120 instruments in the Hand & Foot (H&F) tray were used in at least 1 case. Two instruments were used in all cases, and another 20 instruments were used in at least 50% of the cases. Using a reduced tray with 59 instruments, potential cost savings for tray reduction in 60 cases were estimated to be $2086 without peel-packing and $2356 with peel-packing. The estimated cost savings were lower than those reported in literature due to a reduced scope and exclusion of OR time cost in the analysis. CONCLUSIONS: Instrument oversupply drives cost at our institution's ambulatory surgery center. Ethnography is a cost-effective method to track instrument utilization and determine optimal tray composition for small services but is not scalable to large health systems. The time and cost required to observe sufficient surgeries to enable supply reduction to motivate the need for more efficient methods to determine instrument utility.

Measuring small field profiles and output factors with a stemless plastic scintillator array.

PURPOSE: To fabricate a 1D stemless plastic scintillation detector (SPSD) array using organic photodiodes and to use the detector to measure small field profiles and output factors. METHODS: An organic photodiode array was fabricated by spin coating a mixture of P3HT and PCBM organic semiconductors onto an ITO-coated glass substrate and depositing aluminum top contacts. Four bulk scintillators of various dimensions were placed on top of the photodiode array. A fifth scintillator was used that had been segmented by laser etching and the septa filled with black paint. Each detector array was first calibrated using a reference field of 95 cm SSD, 5 cm depth, and 10 × 10 cm2 field size for a 6 MV photon beam. After calibration, profiles were measured for three small field sizes: 0.5 × 0.5 cm2 , 1 × 1 cm2 , and 2 × 2 cm2 . Using the central pixel of the array, output factors were measured for field sizes of 0.5 × 0.5 cm2 to 25 × 25 cm2 . Small field profiles were compared to film measurements and output factors compared to ion chamber measurements. RESULTS: The segmented scintillator measured profiles that were in good agreement with film for all three field sizes. Output factors agreed to within 1.2% of ion chamber over the field size range of 1 × 1 cm2 to 25 × 25 cm2 . At 0.5 × 0.5 cm2 the segmented scintillator underestimated the output factor compared to film and a microDiamond detector. Bulk scintillators failed to produce a good agreement with film for measured profiles and deviations from ion chamber for output factors were apparent at field sizes below 5 × 5 cm2 . In comparison to a bulk scintillator of dimensions 5 × 5 × 0.5 cm3 the etched scintillator saw a reduction of 5.1, 7.1, and 10.5 times the signal for field sizes of 0.5 × 0.5 cm2 , 1 × 1 cm2 , and 2 × 2 cm2 , respectively. The reduction of signal comes from reduced cross-talk that was present in all of the bulk scintillator geometries to various degrees. CONCLUSION: A 1D SPSD array was demonstrated with various scintillator designs. The etched scintillator array demonstrated excellent small field profile measurements when compared to film and output factors (down to 1 × 1 cm2 field size) when compared to micro ion chamber and diamond detector measurements.

Dual-axis cubic cavity for drift-compensated multi-wavelength laser stabilisation.

We describe a 'clock control unit' based on a dual-axis cubic cavity (DACC) for the frequency stabilisation of lasers involved in a strontium optical lattice clock. The DACC, which ultimately targets deployment in space applications, provides a short-term stable reference for all auxiliary lasers-i.e. cooling, clear-out, and optical lattice-in a single multi-band cavity. Long-term cavity drift is compensated by a feed-forward scheme exploiting a fixed physical relation to an orthogonal second cavity axis; either by reference to an ultrastable 698 nm clock laser, or by exploiting the differential drift between orthogonal axes extracted by a single laser in common view. Via a change of mirror set in the cavity axis accessed by the clock laser, the system could also provide stabilisation for sub-Hz linewidths at the 698 nm clock wavelength, fulfilling all stabilisation requirements of the clock.

3D printed architected conducting polymer hydrogels.

Conducting polymer hydrogels combine electrical conductivity and tunable water content, rendering them strong candidates for a range of applications including biosensors, cell culture platforms, and energy storage devices. However, these hydrogels are mechanically brittle and prone to damage, prohibiting their use in emerging applications involving dynamic movement and large mechanical deformation. Here, we demonstrate that applying the concept of architecture to conducting polymer hydrogels can circumvent these impediments. A stereolithography 3D printing method is developed to successfully fabricate such hydrogels in complex lattice structures. The resulting hydrogels exhibit elastic compressibility, high fracture strain, enhanced cycling stability, and damage-tolerant properties despite their chemical composition being identical to their brittle, solid counterparts. Furthermore, concentrating the deformation to the 3D geometry, rather than polymer microstructure, effectively decouples the mechanical and electrical properties of the hydrogel lattices from their intrinsic properties associated with their chemical composition. The confluence of these new physical properties for conducting polymer hydrogels opens broad opportunities for a myriad of dynamic applications.

Radiofrequency Identification Track for Tray Optimization: An Instrument Utilization Pilot Study in Surgical Oncology.

BACKGROUND: Surgical instrument tray reduction attempts to minimize intraoperative inefficiency and processing costs. Previous reduction methods relied on trained observers manually recording instrument use (i.e. human ethnography), and surgeon and/or staff recall, which are imprecise and inherently limited. We aimed to determine the feasibility of radiofrequency identification (RFID)-based intraoperative instrument tracking as an effective means of instrument reduction. METHODS: Instrument trays were tagged with unique RFID tags. A RFID reader tracked instruments passing near RFID antennas during 15 breast operations performed by a single surgeon; ethnography was performed concurrently. Instruments without recorded use were eliminated, and 10 additional cases were performed utilizing the reduced tray. Logistic regression was used to estimate odds of instrument use across cases. Cohen's Kappa estimated agreement between RFID and ethnography. RESULTS: Over 15 cases, 37 unique instruments were used (median 23 instruments/case). A mean 0.64 (median = 0, range = 0-3) new instruments were added per case; odds of instrument use did not change between cases (OR = 1.02, 95%CI 1.00-1.05). Over 15 cases, all instruments marked as used by ethnography were recorded by RFID tracking; 7 RFID-tracked instruments were never recorded by ethnography. Tray size was reduced 40%. None of the 25 eliminated instruments were required in 10 subsequent cases. Cohen's Kappa comparing RFID data and ethnography over all cases was 0.82 (95%CI 0.79-0.86), indicating near perfect agreement between methodologies. CONCLUSIONS: Intraoperative RFID instrument tracking is a feasible, data-driven method for surgical tray reduction. Overall, RFID tracking represents a scalable, systematic, and efficient method of optimizing instrument supply across procedures.

Diagnosis and treatment of substance use disorder among pregnant women in three state Medicaid programs from 2013 to 2016.

Substance use disorder (SUD) during pregnancy increases risks of adverse outcomes for mothers and children. Because Medicaid covers about half of all births and maternal SUD is a costly problem, describing the timing of enrollment and health care that Medicaid-enrolled pregnant women with SUDs receive is critical to understanding gaps in the timeliness and specificity of SUD diagnosis and treatment for pregnant women with SUDs. We used linked maternal and infant Medicaid claims and enrollment data and infant birth records from three states (n=72,086 mother-infant dyads) to estimate the share of sample women diagnosed with a specified SUD (e.g., opioid use disorder) before or during the birth month, with a specified SUD after the birth month, and with only an unspecified SUD diagnosed (e.g., drug use disorder complicating pregnancy). We also examined the timing of first observed Medicaid enrollment, SUD diagnosis and treatment, and maternal and infant costs. In the 24 months surrounding birth, 3.6% of women had a specified SUD diagnosis first observed before or during the birth month, 1.7% had a specified SUD diagnosis first observed after the birth month, and 6.0% had an SUD diagnosis that was not specified. Most women with a specified SUD diagnosis were enrolled in Medicaid before or early in pregnancy and initiated prenatal care in the first or second trimester, yet nearly one-third of these women received their specified SUD diagnosis after the birth month. Less than two-thirds of women with a specified SUD diagnosis received any SUD treatment during the study period (59.9% among those identified before or during the birth month and 63.1% among those observed after the birth month), and women with an unspecified SUD were about half as likely to get treatment (28.6%). Among treated women, more than two-thirds had the first observed treatment in the same month as their first observed SUD diagnosis. Findings point to a critical need for interventions as well as substantial opportunities to improve the identification of substance use-related needs and provision of treatment among women who birth in Medicaid. Changes in Medicaid and other public policy to reduce disincentives for pregnant and parenting women to report substance use during medical visits and to increase providers' abilities and motivation to equitably screen for as well as treat women with SUDs before, during, and after pregnancy could improve outcomes for mothers and their children. Improvements in SUD diagnosis would also improve prevalence estimates of specific types of SUD, which could contribute to better Medicaid policies aimed at prevention and treatment.

Intensive Approaches to Prenatal Care May Reduce Risk of Gestational Diabetes.

Objectives: To observe gestational diabetes mellitus (GDM) prevalence among participants receiving enhanced prenatal care through one of three care models: Birth Centers, Group Prenatal Care, and Maternity Care Homes. Materials and Methods: This study draws upon data collected from 2014 to 2017 as part of the Strong Start II evaluation and includes data from nearly 46,000 women enrolled across 27 awardees with more than 200 sites throughout the United States. Descriptive and statistical analyses utilized data from participant surveys completed upon entry to the program and a limited chart review. Results: A total of 6.3% of Strong Start participants developed GDM during their pregnancy. Rates varied significantly and substantially by model. After adjusting for participant risk factors, we find that Birth Center participants of all races and ethnicities experienced significantly lower rates of GDM than women of the same race/ethnicity in Maternity Care Homes. Conclusions: The lower rates of gestational diabetes among women receiving Birth Center prenatal care suggest the need for further investigation of how prenatal care approaches can reduce GDM and address health disparities.

Understanding the impact of a new pharmacy sore throat test and treat service on patient experience: A survey study.

BACKGROUND: A pilot of the first NHS funded Sore Throat Test and Treat (STTT) service in the United Kingdom began in selected community pharmacies in Wales in November 2018. The aim of this research was to explore whether a pharmacist delivering consultation for sore throat that included clinical scoring and point-of-care testing was acceptable to patients and how this might influence future health-seeking behaviour. METHODS: A non-experimental design was employed using a survey research tool including a mix of closed and open questions. The patient experience survey was distributed to all patients who had completed a consultation between November 2018 and May 2019. Data from completed surveys were entered in Jisc Online Surveys® and exported to Excel® for descriptive statistics. Free-text comments were analysed using content and inductive thematic analysis. RESULTS: A total of 510 surveys were received (n = 2,839 total consultations, response rate 18%). Overall, 501 patients (98%) were satisfied with the service. Patients' confidence in managing their condition and service satisfaction was not dependent on having been supplied antibiotics. After the service, 504 patients (99%) stated that they would return to the pharmacy for subsequent sore throat symptoms. Three themes were constructed after inductive analysis of free-text comments (n = 242): convenience and accessibility; professionalism of pharmacy team; and perceived value of the service. CONCLUSIONS: Results confirmed high levels of patient satisfaction with the new service, its delivery and the choice of options offered for sore throat symptom management. Whilst this research can only discuss patients' reported future behaviour, the patient-reported stated intentions signify a potential shift in health-seeking behaviour towards a pharmacist-led service. This has important implications in supporting the long-term plan of the governments in Wales and England to redirect management of uncomplicated conditions from GPs to pharmacies.

Determinants of diarrhoeal diseases and height-for-age z-scores in children under five years of age in rural central Tanzania.

INTRODUCTION: Childhood diarrhoeal diseases and stunting are major health problems in low- and middle-income countries (LMICs). Poor water supply, sanitation services and hygiene, frequently encountered in resource-poor settings, contribute to childhood diarrhoea and stunting. METHODS: Data on demographic characteristics, hygiene practices, sanitation and human-animal interactions (predictors) and child height-for-age z-scores (HAZ) (outcome) were collected once, while diarrhoea incidences were collected fortnightly for 24 months (outcome). RESULTS: Drinking water from public taps (OR = 0.51, 95% CI. 0.44-0.61; p < 0.001) and open wells (OR = 0.46, 95% CI. 0.39-0.54; p < 0.001) and older age of children (OR = 0.43, 95% CI. 0.27-0.67; p < 0.001) were protective against diarrhoea. Inappropriate disposal of children's faeces (OR = 1.15, 95% CI. 1.02-1.31; p = 0.025), sharing water sources with animals in the dry season (OR = 1.48, 95% CI. 1.29-1.70; p < 0.001), overnight sharing of houses with cats (OR = 1.35, 95% CI. 1.16-1.57; p < 0.001) and keeping chickens inside the house overnight regardless of room (OR = 1.39, 95% CI. 1.20-1.60; p < 0.001) increased the risk of diarrhoea. The Sukuma language group (p = 0.005), washing hands in running water (p = 0.007), access of chickens to unwashed kitchen utensils (p = 0.030) and overnight sharing of the house with sheep (p = 0.020) were associated with higher HAZ in children. CONCLUSIONS: Until a more precise understanding of the key risk factors is available, these findings suggest efforts towards control of diarrhoea and improved linear growth in these areas should be directed to increased access to clean and safe water, hand-washing, sanitation, and improved animal husbandry practices.

Fabrication and characterization of a stemless plastic scintillation detector.

PURPOSE: To fabricate a stemless plastic scintillation detector (SPSD) and characterize its linearity and reproducibility, and its dependence on energy and dose per pulse; and to apply it to clinical PDD and output factor measurements. METHODS: An organic bulk heterojunction photodiode was fabricated by spin coating a blend of P3HT and PCBM onto an ITO-coated glass substrate and depositing aluminum top contacts. Eljen scintillators (~5 × 5 × 5 mm3 ; EJ-204, EJ-208, and EJ-260) or Saint-Gobain scintillators (~3 × 3 × 2 mm3 ; BC-400 and BC-412) were placed on the opposite side of the glass using a silicone grease (optical coupling agent) creating the SPSD. Energy dependence was measured by using 100, 180, and 300 kVp photon beams from an orthovoltage treatment unit (Xstrahl 300) and 6 and 10 MV photons from a Varian TrueBeam linear accelerator. Linearity, dose per pulse dependence, output factors, and PDDs were measured using a 6 MV photon beam. PDDs and output factors were compared to ion chamber measurements. A control device was fabricated by substituting polystyrene (PS) for the P3HT/PCBM layer. No photocurrent should be generated in the control device and so any current measured is due to Compton current in the electrodes, wires, and surroundings from the irradiation. Output factors were corrected by subtracting the signal measured using the control device from the photodiode measured signal to yield the photocurrent. RESULTS: Each SPSD had excellent linearity with dose having an r2 of 1 and sensitivities of 1.07 nC/cGy, 1.04 nC/cGy, 1.00 nC/cGy and 0.10 nC/cGy, and 0.10 nC/cGy for EJ-204, EJ-208, EJ-260 (5 × 5 × 5 mm3 volumes), BC-400, and BC-412 (3 × 3 × 2 mm3 volumes), respectively. No significant dose per pulse dependence was measured. Output factors matched within 1% for the large scintillators for field sizes of 5 × 5 cm2 to 25 × 25 cm2 , but there was a large under-response at field sizes below 3 × 3 cm2 . After correcting the signal of the small scintillators by subtracting the current measured using the PS control, the output factors agreed with the ion chamber measurements within 1% from field sizes 1 × 1 cm2 to 20 × 20 cm2 . The impact of Cerenkov emissions in the scintillator was effectively corrected with a simple reflective coating on the scintillator. In comparison to a 6 MV photon beam, the large scintillator SPSDs exhibited 37%, 52%, and 73% of the response at energies 100 kVp, 180 kVp and 300 kVp, respectively. CONCLUSION: The principle of the SPSD was demonstrated. Devices had excellent linearity, reproducibility, and no significant dose per pulse dependence, and a simple reflective coating was sufficient to correct for Cerenkov emissions from within the scintillator. The devices demonstrated similar energy dependence to other scintillator detectors used in a radiotherapy setting.