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The only known way to study quantum field theories in nonperturbative regimes is using numerical calculations regulated on discrete space-time lattices. Such computations, however, are often faced with exponential signal-to-noise challenges that render key physics studies untenable even with next generation classical computing. Here, a method is presented by which the output of small-scale quantum computations on noisy intermediate-scale quantum era hardware can be used to accelerate larger-scale classical field theory calculations through the construction of optimized interpolating operators. The method is implemented and studied in the context of the 1+1-dimensional Schwinger model, a simple field theory which shares key features with the standard model of nuclear and particle physics.
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Aims Our aim was to assess if outcomes for cystic fibrosis (CF) patients at six & sixteen years of age have improved in the last 17 years looking at FEV1, BMI and death. Methods A retrospective observational study using a prospectively maintained database of CF patients at Cork University Hospital. Results 84 patients were included in the 16-year-old data and 89 patients were included in the six-year-old data. The mean FEV1 and BMI (16 years) for the 2002-2007 group was 72.9±21.0% and 18.9±2.53 respectively, 2008-2013 group was 75.4±27.2% and 19.8±2.7 and for the 2014-2018 group was 95.2±16.0% and 22.9±4.1. The percentage of patients (16 years) with chronic pseudomonas status was 37.9% (11/30) in the 2002-2007 group, 51.6 % (16/31) in the 2008-2013 group and 4.2% (1/24) in the 2014-2018 group. The relationship between FEV1 and FVC with BMI remained significant in multivariate analysis (P <0.001). The mean FEV1 (six years) for the 2002-2007 group was 90.7±16.1%, 2008-2013 group was 99.3±17.9% and for the 2014-2018 group was 100.9±15.8%. Conclusions Improvements in FEV1 and BMI aged six and 16 years are notable as well as a significant decline in the number of patients with chronic pseudomonas.
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The distributions of pressure and shear forces inside the proton are investigated using lattice quantum chromodynamics (LQCD) calculations of the energy momentum tensor, allowing the first model-independent determination of these fundamental aspects of proton structure. This is achieved by combining recent LQCD results for the gluon contributions to the energy momentum tensor with earlier calculations of the quark contributions. The utility of LQCD calculations in exploring, and supplementing, the assumptions in a recent extraction of the pressure distribution in the proton from deeply virtual Compton scattering is also discussed. Based on this study, the target kinematics for experiments aiming to determine the pressure and shear distributions with greater precision at Thomas Jefferson National Accelerator Facility and a future electron ion collider are investigated.
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BACKGROUND: Current literature highlights higher prevalence rates of sleep difficulties amongst adults with an intellectual disability. However, no synthesis has been conducted to assess the effectiveness of existing interventions in this population. Thus, the aim of this review was to assess the effectiveness of sleep interventions in adults with an intellectual disability (ID). METHOD: Eight databases were searched to identify interventions for sleep difficulties amongst adults with an ID. The study quality was assessed with the Risk Of Bias In Non-randomised Studies - of Interventions. Nine studies (n = 97) were eligible for inclusion in the review. RESULTS: There was a notable study on heterogeneity in terms of the population, study design, intervention studied, sleep assessment and outcome assessments used. Eight of the nine studies reported improvement in sleep following intervention. However, these findings need additional support as only 97 participants involving a variety of interventions and measurement systems were used across all studies. Furthermore, eight of the nine studies had serious to critical risk of bias. The only study identified as having low risk of bias was a placebo-controlled randomised controlled trial for the use of melatonin. CONCLUSIONS: This review highlights the need for objective measures such as actigraphy and studies with greater experimental control investigating sleep interventions in adults with ID.
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Discapacidad Intelectual , Trastornos del Sueño-Vigilia/diagnóstico , Trastornos del Sueño-Vigilia/terapia , Adulto , Comorbilidad , Humanos , Discapacidad Intelectual/epidemiología , Trastornos del Sueño-Vigilia/epidemiologíaRESUMEN
The strange contribution to the electric and magnetic form factors of the nucleon is determined at a range of discrete values of Q^{2} up to 1.4 GeV^{2}. This is done by combining a recent analysis of lattice QCD results for the electromagnetic form factors of the octet baryons with experimental determinations of those quantities. The most precise result is a small negative value for the strange magnetic moment: G_{M}^{s}(Q^{2}=0)=-0.07±0.03µ_{N}. At larger values of Q^{2} both the electric and magnetic form factors are consistent with zero to within 2 standard deviations.
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BACKGROUND AND PURPOSE: Greater occipital nerve blockade (GONB) has been shown to be effective in episodic cluster headache. However, its use in chronic cluster headache (CCH) is less certain. The study aims to prospectively assess the efficacy and consistency of response to GONB in a large series of CCH patients. METHODS: CCH patients who had a unilateral GONB and were referred to the National Hospital for Neurology and Neurosurgery were studied prospectively. Headache characteristics were collected using headache diaries. Responders were considered to be patients with a complete or partial response lasting at least 7 days. In a subgroup of responders the outcomes of serial GONB performed at 3-monthly intervals were also analysed. RESULTS: Eighty-three CCH patients were studied. After the first GONB, a positive response was observed in 47 (57%) patients: 35 (42%) were rendered pain free, 12 (15%) had a partial benefit and one patient obtained <50% improvement. The duration of a positive response lasted a median of 21 days (range 7-504 days). There was a transient worsening of condition in 6% of patients. The overall rate and average duration of response remained consistent after the second [n = 37; 31 responders (84%); median duration 21 days], third [n = 28; 20 responders (71%); median duration 25 days] and fourth [n = 14; 10 responders (71%); median duration 23 days] injections. CONCLUSION: GONB seems to be an efficacious treatment with reproducible effects in CCH patients. Performed three monthly, GONB may have a useful role in the management of CCH.
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Analgésicos/uso terapéutico , Cefalalgia Histamínica/tratamiento farmacológico , Lidocaína/uso terapéutico , Metilprednisolona/uso terapéutico , Bloqueo Nervioso/métodos , Adulto , Anciano , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
AIMS: The study goals were to determine the relationship between faecal indicator bacteria (FIB), the HF183 marker and land use, and the phylogenetic diversity of HF183 marker sequences in a tropical urban watershed. METHODS AND RESULTS: Total coliforms, Escherichia coli, and HF183 were quantified in 81 samples categorized as undeveloped, residential and horticultural from the Kranji Reservoir and Catchment in Singapore. Quantitative-PCR for HF183 followed by analysis of variance indicated that horticultural areas had significantly higher geometric means for marker levels (4·3 × 10(4) HF183-GE 100 ml(-1)) than nonhorticultural areas (3·07 × 10(3) HF183-GE 100 ml(-1)). E. coli and HF183 were moderately correlated in horticultural areas (R = 0·59, P = 0·0077), but not elsewhere in the catchment. Initial upstream surveys of candidate sources revealed elevated HF183 in a wastewater treatment effluent but not in aquaculture ponds. The HF183 marker was cloned, sequenced and determined by phylogenetic analysis to match the original marker description. CONCLUSION: We show that quantification of the HF183 marker is a useful tool for mapping the spatial distribution and potential sources of human sewage contamination in tropical environments such as Singapore. SIGNIFICANCE AND IMPACT: A major challenge for assessment of water quality in tropical environments is the natural occurrence and nonconservative behaviour of FIB. The HF183 marker has been employed in temperate environments as an alternative indicator for human sewage contamination. Our study supports the use of the HF183 marker as an indicator for human sewage in Singapore and motivates further work to determine HF183 marker levels that correspond to public health risk in tropical environments.
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Bacteroides/aislamiento & purificación , Microbiología del Agua , Bacteroides/clasificación , Bacteroides/genética , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Heces/microbiología , Marcadores Genéticos , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Aguas del Alcantarillado/microbiología , Singapur , Clima Tropical , Calidad del AguaRESUMEN
The relatively small fraction of the spin of the proton carried by its quarks presents a major challenge to our understanding of the strong interaction. Traditional efforts to explore this problem have involved new and imaginative experiments and QCD based studies of the nucleon. We propose a new approach to the problem that exploits recent advances in lattice QCD. In particular, we extract values for the spin carried by the quarks in other members of the baryon octet in order to see whether the suppression observed for the proton is a general property or depends significantly on the baryon structure. We compare these results with the values for the spin fractions calculated within a model that includes the effects of confinement, relativity, gluon exchange currents, and the meson cloud required by chiral symmetry, finding a very satisfactory level of agreement given the precision currently attainable.
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Recent lattice QCD calculations have reported evidence for the existence of a bound state with strangeness -2 and baryon number 2 at quark masses somewhat higher than the physical values. By developing a description of the dependence of this binding energy on the up, down and strange quark masses that allows a controlled chiral extrapolation, we explore the hypothesis that this state is to be identified with the H dibaryon. Taking as input the recent results of the HAL and NPLQCD Collaborations, we show that the H dibaryon is likely to be unbound by 13±14 MeV at the physical point.
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Cds1, a serine/threonine kinase, enforces the S-M checkpoint in the fission yeast Schizosaccharomyces pombe. Cds1 is required for survival of replicational stress caused by agents that stall replication forks, but how Cds1 performs these functions is largely unknown. Here we report that the forkhead-associated-1 (FHA1) protein-docking domain of Cds1 interacts with Mus81, an evolutionarily conserved damage tolerance protein. Mus81 has an endonuclease homology domain found in the XPF nucleotide excision repair protein. Inactivation of mus81 reveals a unique spectrum of phenotypes. Mus81 enables survival of deoxynucleotide triphosphate starvation, UV radiation, and DNA polymerase impairment. Mus81 is essential in the absence of Bloom's syndrome Rqh1 helicase and is required for productive meiosis. Genetic epistasis studies suggest that Mus81 works with recombination enzymes to properly replicate damaged DNA. Inactivation of Mus81 triggers a checkpoint-dependent delay of mitosis. We propose that Mus81 is involved in the recruitment of Cds1 to aberrant DNA structures where Cds1 modulates the activity of damage tolerance enzymes.
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Daño del ADN , Proteínas de Unión al ADN/metabolismo , Endonucleasas , Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas , Proteínas de Schizosaccharomyces pombe , Secuencia de Aminoácidos , Quinasa de Punto de Control 2 , Secuencia Conservada , ADN Helicasas/metabolismo , Replicación del ADN , Meiosis , Mitosis , Datos de Secuencia Molecular , Fosforilación , Pruebas de Precipitina , Unión Proteica , Estructura Terciaria de Proteína , Tolerancia a Radiación , Proteínas de Saccharomyces cerevisiae , Schizosaccharomyces , Homología de Secuencia de Aminoácido , Rayos UltravioletaRESUMEN
The protein kinase Chk1 enforces the DNA damage checkpoint. This checkpoint delays mitosis until damaged DNA is repaired. Chk1 regulates the activity and localization of Cdc25, the tyrosine phosphatase that activates the cdk Cdc2. Here we report that Mik1, a tyrosine kinase that inhibits Cdc2, is positively regulated by the DNA damage checkpoint. Mik1 is required for checkpoint response in strains that lack Cdc25. Long-term DNA damage checkpoint arrest fails in Deltamik1 cells. DNA damage increases Mik1 abundance in a Chk1-dependent manner. Ubiquitinated Mik1 accumulates in a proteasome mutant, which indicates that Mik1 normally has a short half-life. Thus, the DNA damage checkpoint might regulate Mik1 degradation. Mik1 protein and mRNA oscillate during the unperturbed cell cycle, with peak amounts detected around S phase. These data indicate that regulation of Mik1 abundance helps to couple mitotic onset to the completion of DNA replication and repair. Coordinated negative regulation of Cdc25 and positive regulation of Mik1 ensure the effective operation of the DNA damage checkpoint.
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Daño del ADN , Proteínas Tirosina Quinasas/metabolismo , Proteínas de Schizosaccharomyces pombe , Transducción de Señal , Proteína Quinasa CDC2/metabolismo , Ciclo Celular , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Núcleo Celular/metabolismo , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Cisteína Endopeptidasas , Replicación del ADN , ADN de Hongos/biosíntesis , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fase G2 , Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Mitosis , Complejos Multienzimáticos , Mutagénesis , Complejo de la Endopetidasa Proteasomal , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/fisiología , ARN Mensajero , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Schizosaccharomyces , Ubiquitinas/metabolismo , ras-GRF1/genética , ras-GRF1/metabolismoRESUMEN
BACKGROUND AND AIMS: There is an urgent need to develop new high throughput approaches to phenotype roots in the field. Excavating roots to make direct measurements is labour intensive. An alternative to excavation is to measure soil drying profiles and to infer root activity. METHODS: We grew 23 lines of wheat in 2013, 2014 and 2015. In each year we estimated soil water profiles with electrical resistance tomography (ERT), electromagnetic inductance (EMI), penetrometer measurements and measurements of soil water content. We determined the relationships between the measured variable and soil water content and matric potential. RESULTS: We found that ERT and penetrometer measurements were closely related to soil matric potential and produced the best discrimination between wheat lines. We found genotypic differences in depth of water uptake in soil water profiles and in the extent of surface drying. CONCLUSIONS: Penetrometer measurements can provide a reliable approach to comparing soil drying profiles by different wheat lines, and genotypic rankings are repeatable across years. EMI, which is more sensitive to soil water content than matric potential, and is less effective in drier soils than the penetrometer or ERT, nevertheless can be used to rapidly screen large populations for differences in root activity.
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Surface water contamination by human faecal wastes is a widespread hazard for human health. Faecal indicator bacteria (FIB) are the most widely used indicators to assess surface water quality but are less-human-specific and have the potential to survive longer and/or occur naturally in tropical areas. In this study, 13 wastewater chemicals (chloride, boron, orthosphophate, detergents as methylene blue active substances, cholesterol, cholestanol, coprostanol, diethylhexyl phthalate, caffeine, acetaminophen, ibuprofen, sucralose and saccharin) were investigated in order to evaluate tracers for human faecal and sewage contamination in tropical urban catchments. Surface water samples were collected at an hourly interval from sampling locations with distinct major land uses: high-density residential, low-density residential, commercial and industrial. Measured concentrations were analysed to investigate the association among indicators and tracers for each land-use category. Better correlations were found between different indicators and tracers in each land-use dataset than in the dataset for all land uses, which shows that land use is an important determinant of drain water quality. Data were further segregated based on the hourly FIB concentrations. There were better correlations between FIB and chemical tracers when FIB concentrations were higher. Therefore, sampling programs must be designed carefully to take the time of sampling and land use into account in order to effectively assess human faecal and sewage contamination in urban catchments. FIB is recommended as the first tier in assessment of surface water quality impairment and chemical tracers as the second tier. Acetaminophen and coprostanol are recommended as chemical tracers for high-density residential areas, while chloride, coprostanol and caffeine are recommended for low-density residential areas.
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Bacterias/aislamiento & purificación , Biomarcadores/análisis , Monitoreo del Ambiente , Agua Dulce/análisis , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis , Heces/microbiología , Humanos , Estaciones del Año , Singapur , Clima TropicalRESUMEN
Human faecal contamination poses a widespread hazard for human health. In urban areas, sewer leakage may be an important cause of faecal pollution to surface water. Faecal indicator bacteria (FIB) are the most widely used indicators to monitor surface water quality. However, assessing whether a water body is meeting water quality criteria is made difficult by the high variability of FIB concentrations over time. In this study, the variation of FIB concentration in surface water from tropical urban catchments is investigated. Eleven urban sub-catchments were sampled hourly over 24-hr and samples analysed for FIB. It was found that FIB show a diurnal pattern that is characterised by daytime FIB concentrations that are significantly higher than nighttime FIB concentrations. This observed diurnal variation of FIB closely follows that of sewer flows and contrasts with observations in rural streams where FIB concentrations are known to be low in the daytime and high during the night. Field tracer tests provide qualitative evidence of sewage exfiltration and transport to drains via preferential flow paths. The diurnal FIB variation and field tracer tests indicate the likelihood of surface water contamination due to leaking sewers. The results further suggest that contamination of surface-water drains is likely a widespread problem in tropical urban areas due to extensive drainage networks and the persistence of FIB under tropical conditions. Because of FIB variation over time, the time at which samples are collected is important in being able to capture the daily maximum and minimum FIB concentrations. The Kruskal-Wallis test shows that hourly sampling from 04:00 to 07:00 and from 12:00 to 15:00 results in significantly different FIB concentration (minimum and maximum, respectively). Furthermore, the Wilcoxon-Mann-Whitney test shows that sampling at 12:00 and 14:00 results in significantly higher FIB concentrations, while sampling at 05:00 and 04:00 or 05:00 and 06:00 results in significantly lower FIB concentrations, than sampling at other hours of the day.
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Bacterias/aislamiento & purificación , Monitoreo del Ambiente , Heces/microbiología , Aguas del Alcantarillado/análisis , Aguas Residuales/microbiología , Singapur , Factores de Tiempo , Clima TropicalRESUMEN
Cardiopulmonary bypass frequently causes new postoperative neuropsychologic deficits. To assess whether these deficits could be predicted or limited, we monitored 29 patients receiving bypass intraoperatively with an on-line computerized electroencephalograph. We hypothesized that the 15 patients whose cerebral perfusion pressure was adjusted on the basis of this electroencephalographic data would have fewer postoperative deficits than the 14 patients whose pressure was monitored on the basis of systemic pressure. The results showed that new postoperative cognitive deficits in both groups were less prevalent than in previous studies, but there was not a significant difference in outcomes between the two groups. The intraoperative electroencephalographic records correlated with surgical, but not neuropsychologic, outcome. It is concluded that careful attention to intraoperative cerebral perfusion pressure may decrease the prevalence of postoperative neuropsychologic complications, but that the use of a computerized electroencephalograph does not necessarily contribute to an improved outcome.
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Puente Cardiopulmonar/efectos adversos , Cognición , Electroencefalografía , Presión Intracraneal , Adulto , Anciano , Anciano de 80 o más Años , Computadores , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio/métodos , Periodo PosoperatorioRESUMEN
Faecal specimens from 100 healthy volunteers living in Edinburgh were examined for the presence of antibiotic-resistant bacteria. A high incidence of ampicillin resistance was found as 42% of specimens containing normally sensitive bacteria were resistant to the drug; however, only 12% of the specimens contained trimethoprim-resistant bacteria. There was no detectable resistance to the third-generation cephalosporin, ceftazidime or the 4-quinolone, ciprofloxacin. Identification of the beta-lactamases produced by the ampicillin-resistant isolates demonstrated that the TEM-1 beta-lactamase predominated particularly in E. coli where it was identified in 86% of isolates. Thirty-three percent of the ampicillin-resistant isolates were able to transfer their resistance to E. coli K12 strain J62-2 and analysis of these transconjugants by iso-electric focusing revealed that the TEM-1 beta-lactamase was present in 100% of the transconjugants. Restriction endonuclease fingerprinting of the TEM-1 containing plasmids suggested the presence of an epidemic plasmid in the community.
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In this first multi-centre study in Scotland, 1028 consecutive Gram-negative and staphylococci strains were obtained from four major teaching hospitals. E. coli was the most common organism among both intensive care units (ICUs) (39%) and non-ICU strains (46.6%). The prevalence of antibiotic resistance among E. coli was always higher in isolates from ICUs than non-ICUs: ceftazidime (14.1%, 7.2%), ceftriaxone (12.7%, 6.1%), cefotaxime (15.5%, 8.7%), cefuroxime (28.8%, 20.8%), amoxicillin plus clavulanic acid (52.2%, 38.8%) and gentamicin (7.0%, 2.8%). The highest incidences of resistance were identified among Enterobacter/Citrobacter spp. from ICUs; 43.8%, 41.7%, 45.8%, 54.2%, 87.5% and 10.4% of these organisms were resistant to ceftazidime, ceftriaxone, cefotaxime, cefuroxime, amoxicillin plus clavulanic acid and gentamicin, respectively.
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Successful river water quality modelling requires the specification of an appropriate model structure and process formulation. Both must be related to the compartment structure of running water ecosystems including their longitudinal, vertical, and lateral zonation patterns. Furthermore, the temporal variability of abiotic boundary conditions may be important and must be incorporated by an appropriate choice of model parameters. A six-step decision procedure is proposed to achieve these objectives. The steps address the determination of the following model features: (1) temporal representation (dynamic or steady-state); (2) model dimensionality; (3) mixing; (4) advection; (5) reaction terms; and (6) boundary conditions. Numerical criteria based on process time constants and length scales provide a basis for these decisions.
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Modelos Teóricos , Contaminación del Agua , Toma de Decisiones , Factores de Tiempo , Movimientos del AguaRESUMEN
In this paper, biochemical process equations are presented as a basis for water quality modelling in rivers under aerobic and anoxic conditions. These equations are not new, but they summarise parts of the development over the past 75 years. The primary goals of the presentation are to stimulate communication among modellers and field-oriented researchers of river water quality and of wastewater treatment, to facilitate practical application of river water quality modelling, and to encourage the use of elemental mass balances for the derivation of stoichiometric coefficients of biochemical transformation processes. This paper is part of a series of three papers. In the first paper, the general modelling approach is described; in the present paper, the biochemical process equations of a complex model are presented; and in the third paper, recommendations are given for the selection of a reasonable submodel for a specific application.
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Eutrofización , Modelos Teóricos , Contaminación del Agua , Bacterias Aerobias , Hipoxia , Nitrógeno/metabolismo , Oxígeno/metabolismo , Aguas del AlcantarilladoRESUMEN
The new River Water Quality Model no. 1 introduced in the two accompanying papers by Shanahan et al. and Reichert et al. is comprehensive. Shanahan et al. introduced a six-step decision procedure to select the necessary model features for a certain application. This paper specifically addresses one of these steps, i.e. the selection of submodels of the comprehensive biochemical conversion model introduced in Reichert et al. Specific conditions for inclusion of one or the other conversion process or model component are introduced, as are some general rules that can support the selection. Examples of simplified models are presented.