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1.
Sci Rep ; 14(1): 8032, 2024 04 05.
Article in English | MEDLINE | ID: mdl-38580681

ABSTRACT

This systematic review and meta-analysis aimed to determine the impact of presurgical waiting times on pre-/post-operative joint specific pain and function, health-related quality of life (HRQOL) and perspectives of patients awaiting primary elective total hip (THR) and knee (TKR) replacements. MEDLINE, EMBASE, PUBMED, and CENTRAL databases were searched from inception until 30th January 2023 (CRD42022288128). Secondary literature and unpublished datasets containing paediatric, non-elective, partial, or revision replacement populations were excluded. PRISMA 2020 reporting and GRADE certainty of evidence guidelines were followed. Residual maximum likelihood meta-analysis and linear meta-regression was performed to elucidate the influence of presurgical waiting time. Twenty-six studies were eligible for systematic review and sixteen for meta-analysis, capturing 89,996 patients (60.6% female, mean age 67.4 years) between 2001 and 2022. A significant deterioration in joint function (mean difference (MD):0.0575%; 95% CI 0.0064, 0.1086; p = 0.028(4d.p.); I2 = 73.1%) and HRQOL (MD: 0.05%; 95% CI - 0.0001.0009; p = 0.011(4 d.p.); I2 = 80.6%) was identified per additional day of waiting. Despite qualitative evidence, meta-analysis could not observe a relationship with postoperative outcome data. Patient responses to delayed THR and TKR surgery were unanimously negative. Immediate action should seek to reduce the increased patient anxiety and significant reductions in pre-operative joint functionality and HRQOL associated with prolonged pre-surgical waiting time, whilst mitigating any potential deleterious post-operative effects.


Subject(s)
Arthroplasty, Replacement, Hip , Arthroplasty, Replacement, Knee , Humans , Female , Child , Aged , Male , Quality of Life , Arthroplasty, Replacement, Hip/adverse effects , Knee Joint , Pain, Postoperative
2.
Sci Data ; 10(1): 822, 2023 11 24.
Article in English | MEDLINE | ID: mdl-38001085

ABSTRACT

Transferable and mechanistic understanding of cross-scale interactions is necessary to predict how coastal systems respond to global change. Cohesive datasets across geographically distributed sites can be used to examine how transferable a mechanistic understanding of coastal ecosystem control points is. To address the above research objectives, data were collected by the EXploration of Coastal Hydrobiogeochemistry Across a Network of Gradients and Experiments (EXCHANGE) Consortium - a regionally distributed network of researchers that collaborated on experimental design, methodology, collection, analysis, and publication. The EXCHANGE Consortium collected samples from 52 coastal terrestrial-aquatic interfaces (TAIs) during Fall of 2021. At each TAI, samples collected include soils from across a transverse elevation gradient (i.e., coastal upland forest, transitional forest, and wetland soils), surface waters, and nearshore sediments across research sites in the Great Lakes and Mid-Atlantic regions (Chesapeake and Delaware Bays) of the continental USA. The first campaign measures surface water quality parameters, bulk geochemical parameters on water, soil, and sediment samples, and physicochemical parameters of sediment and soil.

3.
Rev Sci Instrum ; 93(11): 113531, 2022 Nov 01.
Article in English | MEDLINE | ID: mdl-36461459

ABSTRACT

Neutron time-of-flight (nTOF) detectors have been used on Sandia National Laboratories' Z-Machine for inertial confinement fusion and magnetized liner fusion experiments to infer physics parameters including the apparent fuel-ion temperature, neutron yield, the magnetic-radius product (BR), and the liner rho-r. Single-paddle, dual-paddle, and co-axial scintillation nTOF detectors are used in axial lines-of-sight (LOS) and LOS that are 12° from the midplane. Detector fabrication, characterization, and calibration are discussed.

4.
Rev Sci Instrum ; 93(10): 103514, 2022 Oct 01.
Article in English | MEDLINE | ID: mdl-36319333

ABSTRACT

In inertial confinement fusion experiments, the neutron yield is an important metric for thermonuclear fusion performance. Neutron activation diagnostics can be used to infer neutron yields. The material used for neutron activation diagnostic undergoes a threshold reaction so that only neutrons having energies above the threshold energy are observed. For thermonuclear experiments using deuterium (D) and tritium (T) fuel constituents, neutrons arising from D + D reactions (DD-neutrons) and neutrons resulting from D + T reactions (DT-neutrons) are of primary interest. Indium has two neutron activation reactions that can be used to infer yields of DD-neutrons and DT-neutrons. One threshold is high enough that only DT-neutrons can induce activation, the second reaction can be activated by both DD-neutrons and DT-neutrons. Thus, to obtain the DD-neutron yield, the contribution made by DT-neutrons to the total induced activity must be extracted. In DD-fuel experiments, DT-neutrons arise from secondary reactions, which are significantly lower in number than primary DD-neutrons, and their contribution to the inferred DD-neutron yield can be ignored. When the DD- and DT-neutron yields become comparable, such as when low tritium fractions are added to DD-fuel, the contribution of DT-neutrons must be extracted to obtain accurate yields. A general method is described for this correction to DD-neutron yields.

5.
World Dev ; 148: 105678, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34866757

ABSTRACT

The need for food systems to generate sustainable and equitable benefits for all is a global imperative. However, whilst ample evidence exists linking smallholder farmer coordination and aggregation (i.e. the collective transport and marketing of produce on behalf of multiple farmers) to improved market participation and farmer incomes, the extent to which interventions that aim to improve farmer market engagement may co-develop equitable consumer benefits remains uncertain. This challenge is pertinent to the horticultural systems of South Asia, where the increasing purchasing power of urban consumers, lengthening urban catchments, underdeveloped rural infrastructures and inadequate local demands combine to undermine the delivery of fresh fruits and vegetables to smaller, often rural or semi-rural markets serving nutritionally insecure populations. To this end, we investigate the potential for aggregation to be developed to increase fruit and vegetable delivery to these neglected smaller markets, whilst simultaneously improving farmer returns. Using an innovative system dynamics modelling approach based on an aggregation scheme in Bihar, India, we identify potential trade-offs between outcomes relating to farmers and consumers in smaller local markets. We find that changes to aggregation alone (i.e. scaling-up participation; subsidising small market transportation; mandating quotas for smaller markets) are unable to achieve significant improvements in smaller market delivery without risking reduced farmer participation in aggregation. Contrastingly, combining aggregation with the introduction of market-based cold storage and measures that boost demand improves fruit and vegetable availability significantly in smaller markets, whilst avoiding farmer-facing trade-offs. Critically, our study emphasises the benefits that may be attained from combining multiple nutrition-sensitive market interventions, and stresses the need for policies that narrow the fruit and vegetable cold storage deficits that exist away from more lucrative markets in developing countries. The future pathways and policy options discovered work towards making win-win futures for farmers and disadvantaged consumers a reality.

6.
Article in English | MEDLINE | ID: mdl-34703966

ABSTRACT

COVID-19 led to the reconfiguration of U.K. orthopaedic trauma services because surgical capacity was threatened in acute centers. We report the 30-day mortality of proximal femoral fractures in older adults treated at an elective orthopaedic center. METHODS: Patients >60 years old who presented with a proximal femoral fracture to any of 4 sites in the regional trauma network were transferred to our elective center for emergency surgery. Care was modeled according to the National Institute for Health and Care Excellence guidelines, and efforts were made to treat all patients within 36 hours. Data were collected prospectively, and mortality outcomes were recorded. RESULTS: Of the 192 patients who presented to the elective orthopaedic center, 167 were treated there. The median age of the latter patients was 88 years (interquartile range, 83 to 79 years). The median Charlson Comorbidity Index was 4 (interquartile range, 4 to 6). The median time from emergency department admission to surgical treatment was 24.5 hours (interquartile range, 18.8 to 34.7 hours). The 30-day rate of mortality was 10.2%. A total of 29 (17.4%) tested positive for COVID-19 during their admission, of whom 10 died, for a case-fatality rate of 34.5%. There were no significant differences in age (p = 0.33) or Charlson Comorbidity Index (p = 0.13) between patients who tested positive and those who did not. There was no significant difference in age between those who tested positive and died and those who tested positive and did not die (p = 0.13), but there was a significant difference in Charlson Comorbidity Index between those subgroups (p = 0.03). CONCLUSIONS: During a pandemic, an elective orthopaedic center can be reconfigured to a surgical center for older patients with proximal femoral fractures with acceptable health-care quality outcomes. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

7.
Int J Obes (Lond) ; 45(7): 1588-1598, 2021 07.
Article in English | MEDLINE | ID: mdl-33947968

ABSTRACT

BACKGROUND: Obesity is a global burden, which significantly increases the risk of non-communicable diseases (NCDs). More than a quarter of adults in the United Kingdom are obese, but prevalence varies by ethnicity, and South Asians have the largest burden of NCDs. This paper assesses how sex, generation, and region interplay to vary the predisposition to obesity-related (OR) NCDs among UK Bangladeshis. METHODS: We used National Institute for Health and Care Excellence suggested grading for combining body mass index and waist circumference to define populations at risk of OR-NCDs. Data from 517 adults of Bangladeshi origin from a cross-sectional study (March 2013 to April 2015) were analysed. Male and female participants from London and north-east England were equally sampled including: (1) adult migrants, who came to the UK aged >16 years; (2) child migrants, who came to the UK aged ≤16 years; and (3) second-generation Bangladeshis (who were born and brought up in the UK). A generalised estimating equation using a binomial distribution and a logit link was used to explore the relationship between the binary outcome of being 'at risk of OR-NCDs' and associated factors. RESULTS: Females, married individuals, those living in London, the second-generation, and those of lower self-assessed financial status, with low acculturation status, or who did not walk daily for at least 20 min were more likely to develop OR-NCDs. A striking sex difference was found with more females prone to OR-NCD risk in the north-east than in London. CONCLUSIONS: Our study observed important inter- and intra-regional inequality in OR-NCD risk which worsens the health of ethnic minorities and widens inequality.


Subject(s)
Emigrants and Immigrants/statistics & numerical data , Noncommunicable Diseases/epidemiology , Obesity , Adult , Bangladesh/ethnology , Cross-Sectional Studies , England/epidemiology , Female , Humans , Male , Obesity/complications , Obesity/epidemiology , Risk Factors
8.
Nat Commun ; 12(1): 334, 2021 Jan 12.
Article in English | MEDLINE | ID: mdl-33436570

ABSTRACT

Magnetized plasma interactions are ubiquitous in astrophysical and laboratory plasmas. Various physical effects have been shown to be important within colliding plasma flows influenced by opposing magnetic fields, however, experimental verification of the mechanisms within the interaction region has remained elusive. Here we discuss a laser-plasma experiment whereby experimental results verify that Biermann battery generated magnetic fields are advected by Nernst flows and anisotropic pressure effects dominate these flows in a reconnection region. These fields are mapped using time-resolved proton probing in multiple directions. Various experimental, modelling and analytical techniques demonstrate the importance of anisotropic pressure in semi-collisional, high-ß plasmas, causing a reduction in the magnitude of the reconnecting fields when compared to resistive processes. Anisotropic pressure dynamics are crucial in collisionless plasmas, but are often neglected in collisional plasmas. We show pressure anisotropy to be essential in maintaining the interaction layer, redistributing magnetic fields even for semi-collisional, high energy density physics (HEDP) regimes.

9.
Phys Rev Lett ; 125(15): 155002, 2020 Oct 09.
Article in English | MEDLINE | ID: mdl-33095639

ABSTRACT

We present experimental results from the first systematic study of performance scaling with drive parameters for a magnetoinertial fusion concept. In magnetized liner inertial fusion experiments, the burn-averaged ion temperature doubles to 3.1 keV and the primary deuterium-deuterium neutron yield increases by more than an order of magnitude to 1.1×10^{13} (2 kJ deuterium-tritium equivalent) through a simultaneous increase in the applied magnetic field (from 10.4 to 15.9 T), laser preheat energy (from 0.46 to 1.2 kJ), and current coupling (from 16 to 20 MA). Individual parametric scans of the initial magnetic field and laser preheat energy show the expected trends, demonstrating the importance of magnetic insulation and the impact of the Nernst effect for this concept. A drive-current scan shows that present experiments operate close to the point where implosion stability is a limiting factor in performance, demonstrating the need to raise fuel pressure as drive current is increased. Simulations that capture these experimental trends indicate that another order of magnitude increase in yield on the Z facility is possible with additional increases of input parameters.

10.
Trials ; 21(1): 656, 2020 Jul 16.
Article in English | MEDLINE | ID: mdl-32678053

ABSTRACT

OBJECTIVES: To inform the design of a clinical trial of a targeted screening programme for relatives of individuals affected by thoracic aortic disease, we performed a consensus exercise as to the acceptability of screening, the optimal sequence and choice of tests, long-term patient management, and choice of trial design. METHODS: Working with the Aortic Dissection Awareness UK & Ireland patient association, we performed a Delphi exercise with clinical experts, patients, and carers, consisting of three rounds of consultation followed by a final multi-stakeholder face-to-face workshop. RESULTS: Thirty-five experts and 84 members of the public took part in the surveys, with 164 patients and clinicians attending the final workshop. There was substantial agreement on the need for a targeted screening pathway that would employ a combined approach (imaging + genetic testing). The target population would include the first- and second-degree adult (> 15 years) relatives, with no upper age limit of affected patients. Disagreement persisted about the screening process, sequence, personnel, the imaging method to adopt, computed tomography (CT) scan vs magnetic resonance imaging (MRI), and the specifics of a potential trial, including willingness to undergo randomisation, and measures of effectiveness and acceptability. CONCLUSION: A Delphi process, initiated by patients, identified areas of uncertainty with respect to behaviour, process, and the design of a targeted screening programme for thoracic aortic disease that requires further research prior to any future trial.


Subject(s)
Aortic Diseases/diagnosis , Delphi Technique , Mass Screening , Research Design , Adult , Clinical Trials as Topic , Cost-Benefit Analysis , Humans , Ireland , United Kingdom
11.
Gait Posture ; 79: 229-233, 2020 06.
Article in English | MEDLINE | ID: mdl-32446178

ABSTRACT

BACKGROUND: Increased postural balance challenge is associated with more fluctuations in centre of pressure movement, indicating increased interference from the postural control system. The role of intrinsic foot muscles in balance control is relatively understudied and whether such control system interference occurs at the level of these muscles is unknown. RESEARCH QUESTION: Do fewer fluctuations in intrinsic foot muscle excitation occur in response to increased postural balance challenge? METHODS: Surface EMGs were recorded using a grid of 13 × 5 channels from the plantar surface of the foot of 17 participants, who completed three balance tasks: bipedal stance; single leg stance and bipedal tip-toe. Centre of pressure (CoP) movement was calculated from simultaneously recorded force plate signals. Fluctuations in CoP and EMGs for each task were quantified using a sample entropy based metric, Entropy Halflife (EnHL). Longer EnHL indicates fewer signal fluctuations. RESULTS: The shortest EMG EnHL, 9.27 ± 3.34 ms (median ± interquartile range), occurred during bipedal stance and the longest during bipedal tip-toe 15.46 ± 11.16 ms, with 18.80 ± 8.00 ms recorded for single leg stance. Differences were statistically significant between bipedal stance and both bipedal tip-toe (p < 0.001) and single leg stance (p < 0.001). CoP EnHL for both anterior-posterior and medial-lateral movements also differed significantly between tasks (p < 0.001, both cases). However, anterior-posterior CoP EnHL was longest for bipedal stance 259.84±230.22 ms and shortest for bipedal tip-toe 146.25±73.35 ms. Medial-lateral CoP EnHL was also longest during bipedal stance 215.73±187.58 ms, but shortest for single leg stance 113.48±83.01 ms. SIGNIFICANCE: Fewer fluctuations in intrinsic foot muscle excitation occur in response to increased postural balance challenge. Fluctuations in CoP movement during balance must be predominantly driven by excitation of muscles extrinsic to the foot. Intrinsic foot muscles therefore likely play a greater role in stabilisation of the foot than balance control during the postural tasks studied.


Subject(s)
Foot/physiology , Muscle, Skeletal/physiology , Postural Balance/physiology , Adult , Electromyography , Entropy , Female , Humans , Male , Middle Aged , Movement/physiology , Pressure
12.
J Athl Train ; 54(11): 1129-1139, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31549849

ABSTRACT

CONTEXT: Previous research from a sample of US secondary schools (n = 10 553) indicated that 67% of schools had access to an athletic trainer (AT; 35% full time [FT], 30% part time [PT], and 2% per diem). However, the population-based statistic in all secondary schools with athletic programs (n = approximately 20 000) is yet to be determined. OBJECTIVE: To determine the level of AT services and employment status in US secondary schools with athletics by National Athletic Trainers' Association district. DESIGN: Cross-sectional study. SETTING: Public and private secondary schools with athletics. PATIENTS OR OTHER PARTICIPANTS: Data from all 20 272 US public and private secondary schools were obtained. MAIN OUTCOME MEASURE(S): Data were collected from September 2015 to April 2018 by phone or e-mail communication with school administrators or ATs and by online surveys of secondary school ATs. Employment categories were school district, school district with teaching, medical or university facility, and independent contractor. Data are presented as total number and percentage of ATs. Descriptive statistics were calculated for FT, PT, and no AT services data for public, private, public + private, and employment type by state and by National Athletic Trainers' Association district. RESULTS: Of the 20 272 secondary schools, 66% (n = 13 473) had access to AT services, while 34% (n = 6799) had no access. Of those schools with AT services, 53% (n = 7119) received FT services, while 47% (n = 6354) received PT services. Public schools (n = 16 076) received 37%, 32%, and 31%, whereas private schools (n = 4196) received 27%, 28%, and 45%, for FT, PT, and no AT services, respectively. Most of the Athletic Training Locations and Services Survey participants (n = 6754, 57%) were employed by a medical or university facility, followed by a school district, school district with teaching, and independent contractor. Combined, 38% of AT employment was via the school district. CONCLUSIONS: The percentages of US schools with AT access and FT and PT services were similar to those noted in previous research. One-third of secondary schools had no access to AT services. The majority of AT employment was via medical or university facilities. These data depict the largest and most updated representation of AT services in secondary schools.


Subject(s)
Schools/statistics & numerical data , Sports Medicine/education , Sports/education , Cross-Sectional Studies , Female , Humans , Male , United States
13.
BMC Psychol ; 7(1): 48, 2019 Jul 23.
Article in English | MEDLINE | ID: mdl-31337438

ABSTRACT

BACKGROUND: Alopecia Areata (AA) is an autoimmune condition that is characterised by non-scarring hair loss. Its aesthetic repercussions can lead to profound changes in psychological well-being. Although physical activity (PA) has been associated with better mental health outcomes in diverse populations, the association in individuals with AA has not been established. The aim of this study was to examine the associations between PA and mental health outcomes in individuals with AA to inform intervention strategies for this specific population. METHODS: A cross-sectional study was conducted among individuals who were diagnosed with AA. A total of 83 respondents aged (40.95 ± 13.24 years) completed a self-report questionnaire consisting of International Physical Activity Questionnaire-Short Form (IPAQ-SF) and the Depression and Anxiety Stress Scale (DASS-21). Three-way contingency Chi-square analyses were used to determine the associations between PA, mental health outcomes and participants with hair loss of more than 50% on the scalp. RESULTS: 81.9% of the participants did not meet PA guidelines. Participants with hair loss of more than 50% on the scalp, and who did not meet PA guidelines, were significantly more likely to experience symptoms of severe depression (p = .003), moderate anxiety (p = .04) and mild stress (p = .003) than those who met guidelines CONCLUSION: Findings suggest that increased PA participation in AA individuals with severe hair loss is associated with improved mental health status. Intervention efforts for this specific population should consider barriers and enablers to PA participation as they face challenges that differ from the general population.


Subject(s)
Alopecia Areata/psychology , Anxiety/psychology , Body Image/psychology , Depression/psychology , Self Concept , Adaptation, Psychological , Adult , Cross-Sectional Studies , Exercise , Female , Humans , Male , Middle Aged , Surveys and Questionnaires
14.
Anaesthesia ; 74(12): 1551-1557, 2019 12.
Article in English | MEDLINE | ID: mdl-31228255

ABSTRACT

Particulate corticosteroids have been described to lead to greater pain improvement compared with their non-particulate counterparts when used in epidural injections. It is hypothesised that filtering may significantly impact their concentration and long-term efficacy. We investigated if passing particulate suspensions through different commonly-used filters affects drug dosage. Two particulate corticosteroid formulations, triamcinolone acetonide and methylprednisolone acetate, were mixed at different concentrations with either bupivacaine hydrochloride or 0.9% sodium chloride. Solutions were passed through a 5-µm and a 0.2-µm filter. Mass spectroscopy results indicated a complete loss of corticosteroid from the solutions using both filters, and light microscopy imaging demonstrated agglomerate formation, suggesting that filtering interferes with drug dosage. The choice of diluents must also be considered to reduce large agglomerate formation. Clinicians should be aware of the consequences of filtering particulate suspensions and carefully consider the selection of diluent when considering treatment plans.


Subject(s)
Adrenal Cortex Hormones/administration & dosage , Adrenal Cortex Hormones/chemistry , Chemistry, Pharmaceutical , Drug Compounding , Filtration , Indicator Dilution Techniques , Injections, Epidural , Methylprednisolone/administration & dosage , Methylprednisolone/chemistry , Particle Size , Particulate Matter , Suspensions , Triamcinolone Acetonide/administration & dosage , Triamcinolone Acetonide/chemistry
15.
Bone Joint J ; 101-B(5): 582-588, 2019 05.
Article in English | MEDLINE | ID: mdl-31039037

ABSTRACT

AIMS: The aims of this study were to report the efficacy of revision surgery for patients with co-infective bacterial and fungal prosthetic joint infections (PJIs) presenting to a single institution, and to identify prognostic factors that would guide management. PATIENTS AND METHODS: A total of 1189 patients with a PJI were managed in our bone infection service between 2006 and 2015; 22 (1.85%) with co-infective bacterial and fungal PJI were included in the study. There were nine women and 13 men, with a mean age at the time of diagnosis of 64.5 years (47 to 83). Their mean BMI was 30.9 kg/m2 (24 to 42). We retrospectively reviewed the outcomes of these PJIs, after eight total hip arthroplasties and 14 total knee arthroplasties. The mean clinical follow-up was 4.1 years (1.4 to 8.8). RESULTS: The median number of risk factors for PJI was 5.5 (interquartile range (IQR) 3.25 to 7.25). All seven patients who initially underwent debridement and implant retention (DAIR) had a recurrent infection that led to a staged revision. All 22 patients underwent the first of a two-stage revision. None of the nine patients with negative tissue cultures at the second stage had a recurrent infection. The rate of recurrent infection was significantly higher in the presence of multidrug-resistant bacteria (p = 0.007), a higher C-reactive protein (CRP) at the time of presentation (p = 0.032), and a higher number of co-infective bacterial organisms (p = 0.041). The overall rate of eradication of infection after two and five years was 50% (95% confidence interval (CI) 32.9 to 75.9) and 38.9% (95% CI 22.6 to 67), respectively. CONCLUSION: The risk of failure to eradicate infection with the requirement of amputation associated with this diagnosis is much higher than in patients with PJI without bacterial and fungal co-infection, and this risk is heightened when the fungal organism is joined by polymicrobial and multidrug-resistant bacterial organisms. Cite this article: Bone Joint J 2019;101-B:582-588.


Subject(s)
Bacterial Infections/complications , Mycoses/complications , Prosthesis-Related Infections/surgery , Reoperation/methods , Aged , Aged, 80 and over , Anti-Bacterial Agents/therapeutic use , Arthroplasty, Replacement, Hip/adverse effects , Arthroplasty, Replacement, Knee/adverse effects , Bacterial Infections/surgery , Coinfection , Female , Humans , Male , Middle Aged , Mycoses/surgery , Prognosis , Prosthesis-Related Infections/drug therapy , Prosthesis-Related Infections/microbiology , Retrospective Studies , Risk Factors , Survival Analysis
16.
Philos Trans A Math Phys Eng Sci ; 377(2139): 20180018, 2019 Feb 25.
Article in English | MEDLINE | ID: mdl-30966932

ABSTRACT

Volcanism is the surface expression of magma intrusion, crystallization, assimilation and hybridization processes operating throughout the crust over a range of time periods. Many magmas, including those erupted at subduction zones, have complex textures that reflect these processes. Here, we use textural and geochemical characteristics of calcic amphiboles to help identify multiple ingredients of subduction zone magmatism at Mt Lamington volcano, Papua New Guinea. Our approach uses existing trace element partitioning schemes to calculate the compositions of amphibole equilibrium melts (AEMs). The AEM compositions show that Mt Lamington andesites and plutonic enclaves are dominated by fractionation of amphibole + plagioclase + biotite, with assimilation of plagioclase and zircon. Magnesiohastingsite crystals in the andesite and diktytaxitic mafic enclaves reflect multiple episodes of recharge by more primitive, geochemically variable melts. The andesite also contains clots with rounded grains and melt on grain boundaries. These features indicate slow crystallization, and the retention of melt films could significantly enhance the potential for remobilization of crystals by infiltrating melts or during magma mixing. Variations in crystallization conditions could thus significantly affect the mush microstructure. We suggest that this could result in a significant bias of the volcanic record towards the preferential incorporation of more slowly cooled plutonic material from the lower crust or from more thermally mature plumbing systems. This article is part of the Theo Murphy meeting issue 'Magma reservoir architecture and dynamics'.

17.
Rev Sci Instrum ; 89(10): 10I119, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30399763

ABSTRACT

The apparent ion temperature and neutron-reaction history are important characteristics of a fusion plasma. Extracting these quantities from a measured neutron-time-of-flight signal requires accurate knowledge of the instrument response function (IRF). This work describes a novel method for obtaining the IRF directly for single DT neutron interactions by utilizing n-alpha coincidence. The t(d,α)n nuclear reaction was produced at Sandia National Laboratories' Ion Beam Laboratory using a 300 keV Cockcroft-Walton generator to accelerate a 2.5 µA beam of 175 keV D+ ions into a stationary ErT2 target. The average neutron IRF was calculated by taking a time-corrected average of individual neutron events within an EJ-228 plastic scintillator. The scintillator was coupled to two independent photo-multiplier tubes operated in the current mode: a Hamamatsu 5946 mod-5 and a Photek PMT240. The experimental setup and results will be discussed.

18.
Rev Sci Instrum ; 89(10): 10I121, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30399775

ABSTRACT

The one-dimensional imager of neutrons (ODIN) at the Sandia Z facility consists of a 10-cm block of tungsten with rolled edges, creating a slit imager with slit widths of either 250, 500, or 750 µm. Designed with a 1-m neutron imaging line of sight, we achieve about 4:1 magnification and 500-µm axial spatial resolution. The baseline inertial confinement fusion concept at Sandia is magnetized liner inertial fusion, which nominally creates a 1-cm line source of neutrons. ODIN was designed to determine the size, shape, and location of the neutron producing region, furthering the understanding of compression quality along the cylindrical axis of magnetized liner implosions. Challenges include discriminating neutrons from hard x-rays and gammas with adequate signal-to-noise in the 2 × 1012 deuterium-deuterium (DD) neutron yield range, as well as understanding the point spread function of the imager to various imaging detectors (namely, CR-39). Modeling efforts were conducted with MCNP6.1 to determine neutron response functions for varying configurations in a clean DD neutron environment (without x-rays or gammas). Configuration alterations that will be shown include rolled-edge slit orientation and slit width, affecting the resolution and response function. Finally, the experiment to determine CR-39 neutron sensitivity, with and without a high density polyethylene (n, p) converter, an edge spread function, and resolution will be discussed.

19.
Clin Genet ; 94(1): 174-178, 2018 07.
Article in English | MEDLINE | ID: mdl-29652076

ABSTRACT

As genomic sequencing expands, so does our knowledge of the link between genetic variation and disease. Deeper catalogs of variant frequencies improve identification of benign variants, while sequencing affected individuals reveals disease-associated variation. Accumulation of human genetic data thus makes reanalysis a means to maximize the benefits of clinical sequencing. We implemented pipelines to systematically reassess sequencing data from 494 individuals with developmental disability. Reanalysis yielded pathogenic or likely pathogenic (P/LP) variants that were not initially reported in 23 individuals, 6 described here, comprising a 16% increase in P/LP yield. We also downgraded 3 LP and 6 variants of uncertain significance (VUS) due to updated population frequency data. The likelihood of identifying a new P/LP variant increased over time, as ~22% of individuals who did not receive a P/LP variant at their original analysis subsequently did after 3 years. We show here that reanalysis and data sharing increase the diagnostic yield and accuracy of clinical sequencing.


Subject(s)
Developmental Disabilities/diagnosis , Developmental Disabilities/genetics , Genetic Variation , Genomics , Intellectual Disability/diagnosis , Intellectual Disability/genetics , Alleles , DNA Copy Number Variations , Gene Frequency , Genetic Testing , Genomics/methods , Genotype , Humans , Polymorphism, Single Nucleotide , Exome Sequencing , Whole Genome Sequencing
20.
J Electromyogr Kinesiol ; 39: 149-155, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29506007

ABSTRACT

Intrinsic foot muscles (IFM) are a crucial component within the human foot. Investigating their functioning can help understand healthy and pathological behaviour of foot and ankle, fundamental for everyday activities. Recording muscle activation from IFM has been attempted with invasive techniques, mainly investigating single muscles. Here we present a novel methodology, to investigate the feasibility of recording physiological surface EMG (sEMG) non-invasively and quantify patterns of activation across the whole plantar region of the foot. sEMG were recorded with a 13 × 5 array from the sole of the foot (n = 25) during two-foot stance, two-foot tiptoe and anterior/posterior sways. Physiological features of sEMG were analysed. During anterior/posterior epochs within the sway task, sEMG patterns were analysed in terms of signal amplitude (intensity) and structure (Sample Entropy) distribution, by evaluating the centre of gravity (CoG) of each topographical map. Results suggest signals are physiological and not affected by loading. Both amplitude and sample entropy CoG coordinates were grouped in one region and overlapped, suggesting that the region with highest amplitude corresponds with the most predictable signal. Therefore, both spatial and temporal features of IFM activation may be recorded non-invasively, providing opportunity for more detailed investigation of IFM function in healthy and patient populations.


Subject(s)
Electromyography/methods , Foot/physiology , Muscle, Skeletal/physiology , Adult , Ankle/physiology , Ankle Joint/physiology , Female , Humans , Male , Middle Aged , Time Factors
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