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1.
Phys Rev Lett ; 132(7): 072501, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38427880

RESUMEN

Five previously unknown isotopes (^{182,183}Tm, ^{186,187}Yb, ^{190}Lu) were produced, separated, and identified for the first time at the Facility for Rare Isotope Beams (FRIB) using the Advanced Rare Isotope Separator (ARIS). The new isotopes were formed through the interaction of a ^{198}Pt beam with a carbon target at an energy of 186 MeV/u and with a primary beam power of 1.5 kW. Event-by-event particle identification of A, Z, and q for the reaction products was performed by combining measurements of the energy loss, time of flight, magnetic rigidity Bρ, and total kinetic energy. The ARIS separator has a novel two-stage design with high resolving power to strongly suppress contaminant beams. This successful new isotope search was performed less than one year after FRIB operations began and demonstrates the discovery potential of the facility which will ultimately provide 400 kW of primary beam power.

2.
Geophys Res Lett ; 48(11): e2021GL092700, 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34219832

RESUMEN

A sequence of discrete solar wind structures within the sheath region of an interplanetary coronal mass ejection on November 6, 2015, caused a series of compressions and releases of the dayside magnetosphere. Each compression resulted in a brief adiabatic enhancement of ions (electrons) driving bursts of electromagnetic ion cyclotron (EMIC; whistler mode chorus) wave growth across the dayside magnetosphere. Fine-structured rising tones were observed in the EMIC wave bursts, resulting in nonlinear scattering of relativistic electrons in the outer radiation belt. Multipoint observations allow us to study the spatial structure and evolution of these sheath structures as they propagate Earthward from L1 as well as the spatio-temporal characteristics of the magnetospheric response. This event highlights the importance of fine-scale solar wind structure, in particular within complex sheath regions, in driving dayside phenomena within the inner magnetosphere.

3.
Anaesthesia ; 76(4): 480-488, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33027534

RESUMEN

Postoperative complications are common and may be under-recognised. It has been suggested that enhanced postoperative care in the recovery room may reduce in-hospital complications in moderate- and high-risk surgical patients. We investigated the feasibility of providing advanced recovery room care for 12-18 h postoperatively in the post-anaesthesia care unit. The primary hypothesis was that a clinical trial of advanced recovery room care was feasible. The secondary hypothesis was that this model may have a sustained impact on postoperative in-hospital and post-discharge events. This was a multicentre, prospective, feasibility before-and-after trial of moderate-risk patients (predicted 30-day mortality of 1-4%) undergoing non-cardiac surgery and who were scheduled for postoperative ward care. Patients were managed using defined assessment checklists and goals of care in an advanced recovery room care setting in the immediate postoperative period. This utilised existing post-anaesthesia care unit infrastructure and staffing, but extended care until the morning of the first postoperative day. The advanced recovery room care trial was deemed feasible, as defined by the recruitment and per protocol management of > 120 patients. However, in a specialised cancer centre, recruitment was slow due to low rates of eligibility according to narrow inclusion criteria. At a rural site, advanced recovery room care could not be commenced due to logistical issues in establishing a new model of care. A definitive randomised controlled trial of advanced recovery room care appears feasible and, based on the indicative data on outcomes, we believe this is warranted.


Asunto(s)
Cuidados Posoperatorios/métodos , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Femenino , Cardiopatías/mortalidad , Cardiopatías/cirugía , Hospitales , Humanos , Masculino , Persona de Mediana Edad , Readmisión del Paciente , Periodo Posoperatorio , Sala de Recuperación , Riesgo
4.
Int J Therm Sci ; 137: 534-538, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32021553

RESUMEN

NASA is designing an unmanned submarine to explore the depths of the hydrocarbon-rich seas on Saturn's moon Titan. Data from Cassini indicates that the Titan north polar environment sustains stable seas of variable concentrations of ethane, methane, and nitrogen, with a surface temperature near 93 K. The submarine must operate autonomously, study atmosphere/sea exchange, interact with the seabed, hover at the surface or any depth within the sea, and be capable of tolerating variable hydrocarbon compositions. Currently, the main thermal design concern is the effect of effervescence on submarine operation, which affects the ballast system, science instruments, and propellers. Twelve effervescence measurements on various liquid methane-ethane compositions with dissolved gaseous nitrogen are thus presented from 1.5 bar to 4.5 bar at temperatures from 92 K to 96 K to simulate the conditions of the seas. After conducting effervescence measurements, two freezing point depression measurements were conducted. The freezing liquid line was depressed more than 15 K below the triple point temperatures of pure ethane (90.4 K) and pure methane (90.7 K). Experimental effervescence measurements will be used to compare directly with effervescence modeling to determine if changes are required in the design of the thermal management system as well as the propellers.

5.
Space Weather ; 17(3): 419-437, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33363448

RESUMEN

An interval of exceptional solar activity was registered in early September 2017, late in the decay phase of solar cycle 24, involving the complex Active Region 12673 as it rotated across the western hemisphere with respect to Earth. A large number of eruptions occurred between 4 and 10 September, including four associated with X-class flares. The X9.3 flare on 6 September and the X8.2 flare on 10 September are currently the two largest during cycle 24. Both were accompanied by fast coronal mass ejections and gave rise to solar energetic particle (SEP) events measured by near-Earth spacecraft. In particular, the partially occulted solar event on 10 September triggered a ground-level enhancement (GLE), the second GLE of cycle 24. A further, much less energetic SEP event was recorded on 4 September. In this work we analyze observations by the Advanced Composition Explorer (ACE) and the Geostationary Operational Environmental Satellites (GOES), estimating the SEP event-integrated spectra above 300 keV and carrying out a detailed study of the spectral shape temporal evolution. Derived spectra are characterized by a low-energy break at few/tens of MeV; the 10 September event spectrum, extending up to ~1 GeV, exhibits an additional rollover at several hundred MeV. We discuss the spectral interpretation in the scenario of shock acceleration and in terms of other important external influences related to interplanetary transport and magnetic connectivity, taking advantage of multipoint observations from the Solar Terrestrial Relations Observatory. Spectral results are also compared with those obtained for the 17 May 2012 GLE event.

6.
Br J Dermatol ; 176(3): 759-764, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27664969

RESUMEN

BACKGROUND: Most people with psoriasis have limited disease that could be treated with topicals, but topical efficacy is limited by low short-term adherence. Psoriasis is a chronic disease, and long-term adherence is an even bigger problem. OBJECTIVES: To determine how well medication is used in the long-term topical treatment of psoriasis and to assess the potential of an internet-based reporting intervention to improve treatment adherence and outcomes. METHODS: An investigator-blinded, prospective study evaluated topical fluocinonide adherence in 40 patients with mild-to-moderate psoriasis over 12 months. Subjects were randomized in a 1 : 1 ratio to standard-of-care or internet-based reporting group. Adherence was objectively monitored with Medication Event Monitoring System® caps. RESULTS: Fifty per cent of subjects discontinued the treatment. Greater adherence was seen in the intervention group compared with the standard-of-care group (50% vs. 35%, P = 0·08). Psoriasis Area and Severity Index improved more in the intervention group at month 1 (1·61 vs. -0·12, P = 0·003), month 3 (2·50 vs. 0·79, P = 0·025) and month 12 (3·32 vs. 0·34, P = 0·038) than in the standard-of-care group. CONCLUSIONS: This study likely underestimates the challenge of long-term adherence, as adherence tends to be better in research studies than in clinical practice. This study also did not fully account for primary nonadherence. Adherence to topical treatment is low in the short term and decreased further in the long term, a considerable challenge for dermatologists to address. A reporting intervention may be one of the ways we can improve our patients' treatment outcomes.


Asunto(s)
Fármacos Dermatológicos/administración & dosificación , Fluocinonida/administración & dosificación , Cumplimiento de la Medicación , Psoriasis/tratamiento farmacológico , Administración Cutánea , Adulto , Anciano , Análisis de Varianza , Registros Electrónicos de Salud , Femenino , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Estudios Prospectivos , Adulto Joven
10.
J Public Health (Oxf) ; 36(4): 667-73, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24408903

RESUMEN

BACKGROUND: Reducing preventable sight loss is an increasing priority for public health and health care providers. We examined the factors affecting people's use of optometry services in population groups at increased risk of sight loss. METHODS: This is a qualitative study in five UK locations. In England, participants were from the Pakistani and Black Caribbean communities; in Scotland from the Pakistani community; and in Northern Ireland and Wales from white socio-economically deprived communities. Thirty-four focus groups were conducted (n = 289). The study included people who attend optometry services and people not engaged with services. RESULTS: Barriers to access included limited awareness of eye health and eye disease, concern about the cost of spectacles and the appropriateness of optometry in a commercial setting. Attendance at the optometrist was primarily symptom led. A positive previous experience or continuing relationship with the optometrist helped to alleviate the barriers and promote attendance. CONCLUSION: Addressing the disparity between the broader messages about eye health and the current perception of the function of optometry could help improve access to services. Uptake may be improved through the co-production of interventions that better resonate with local communities. Non-retail service delivery options should be explored.


Asunto(s)
Oftalmopatías/psicología , Conocimientos, Actitudes y Práctica en Salud , Accesibilidad a los Servicios de Salud , Adulto , Anciano , Población Negra , Región del Caribe , Oftalmopatías/prevención & control , Femenino , Grupos Focales , Conocimientos, Actitudes y Práctica en Salud/etnología , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Optometría , Pakistán , Relaciones Profesional-Paciente , Investigación Cualitativa , Reino Unido
11.
Br Poult Sci ; 53(5): 616-22, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23281755

RESUMEN

1. An experiment was conducted with 98 male and 98 female broiler chickens (Ross 308) to study the effect of growth rate, induced by different dietary means, sex and live weight (1500 g and 2000 g) at slaughter on production parameters, bone strength and sensorial characteristics of the breast meat. 2. The birds were divided into four groups and individually fed a standard commercial diet, a high energy diet or low energy diet from d 11 to slaughter at between d 28 and 39. Three groups were fed ad libitum and a further group was fed a restricted amount of the high energy feed. Half of the birds in each group were slaughtered at approximately 1500 g and the other half at 2000 g live weight. 3. The diets resulted in different growth rates. The chickens fed the high energy and the commercial diet had the highest growth rate at both live weights at slaughter. The restricted fed chickens had lower bone strength than the chickens fed the low energy diet. 4. Breast meat from male broilers was juicer, more tender and less hard than breast meat from females. Chickens slaughtered at 2000 g live weight were juicer than those slaughtered at 1500 g. Chickens given the high energy feed ad libitum and restricted had different growth rates, but the sensory parameter related to texture showed no difference. 5. It was concluded that an increased slaughter weight might improve meat quality due to improved juiciness.


Asunto(s)
Huesos/fisiología , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Ingestión de Energía , Carne/normas , Alimentación Animal/análisis , Animales , Peso Corporal , Femenino , Privación de Alimentos/fisiología , Masculino , Factores Sexuales
12.
Mol Cell Biol ; 12(1): 337-46, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1729609

RESUMEN

The lam locus of Aspergillus nidulans consists of two divergently transcribed genes, lamA and lamB, involved in the utilization of lactams such as 2-pyrrolidinone. Both genes are under the control of the positive regulatory gene amdR and are subject to carbon and nitrogen metabolite repression. The lamB gene and the region between the two genes have been sequenced, and the start points of transcription have been determined. Within the lam locus are two sequences with homology to elements, required for AmdR regulation, found in the 5' regions of the coregulated genes amdS and gatA. In vitro and in vivo assays were used to investigate the lam and gatA regulatory elements. One of the three gatA elements and one of the two lam elements were shown to bind AmdR protein in vivo and activate transcription. With a gel shift mobility assay, in vitro binding of AmdR protein to the functional gatA element was detected. Both the functional gatA and lam boxes contain within them a CAAT sequence. In vitro binding analysis indicates that a CCAAT-specific factor(s) binds at these sequences, adjacent to or overlapping the AmdR protein-binding site.


Asunto(s)
Aspergillus nidulans/genética , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Genes Reguladores , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Clonación Molecular , ADN de Hongos , Proteínas Fúngicas/metabolismo , Datos de Secuencia Molecular , Mapeo Restrictivo , Transformación Genética
13.
Chem Biodivers ; 4(10): 2315-31, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17955459

RESUMEN

The phenomenological calculus is a categorical example of Robert Rosen's modeling relation. This paper is an alligation of the phenomenological calculus and generalized harmonic analysis, another categorical example. Our epistemological exploration continues into the realm of Wiener description space, in which constitutive parameters are extended from vectors to vector-valued functions of a real variable. Inherent in the phenomenology are fundamental representations of time and nearness to equilibrium.


Asunto(s)
Modelos Teóricos , Biología de Sistemas
14.
J Mol Biol ; 228(1): 302-5, 1992 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-1447790

RESUMEN

Single crystals of methanol dehydrogenase (MDH) from Methylobacterium extorquens AM1 have been grown by the vapour diffusion method. These crystals diffract to beyond 2 A resolution and are suitable for X-ray crystallography. They belong to the orthorhombic space group P2(1)2(1)2(1) and have the following unit cell parameters: a = 66.79 A, b = 108.9 A, c = 188.9 A. One asymmetric unit contains an alpha 2 beta 2 tetramer of MDH and the location of the non-crystallographic 2-fold symmetry axis of this tetramer is defined by the paired positions of the binding sites of heavy atoms in four MDH-derivatives.


Asunto(s)
Oxidorreductasas de Alcohol/química , Bacterias Aerobias Gramnegativas/enzimología , Cristalización , Difracción de Rayos X
15.
Pain ; 66(1): 13-22, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8857627

RESUMEN

Inpatient and outpatient cognitive behavioural pain management programmes for mixed chronic pain patients were compared. Patients were randomly allocated to the 4 week inpatient programme or to the 8 half day per week outpatient programme, or to a waiting list control group. Staff, teaching materials, and setting were the same for the two treatment groups. Patients were assessed pre-treatment, and at 1 month after discharge, and treated patients also at 6 months and 1 year after discharge, by assessors blind to treatment group; assessments included physical, functional and psychological measures, and medication use. In total, 121 mixed chronic pain patients (mean age 50 years; mean chronicity 8.1 years) were included in the study, following medical examination to ensure that no further medical treatment was appropriate. There was no change in the control group; inpatients and outpatients, comparable before treatment, both made significant improvements in physical performance and psychological function, and reduced medication use. Inpatients made greater gains, and maintained them better at 1 year; they also used less health care than outpatients. There were no outstanding predictors of improvement other than treatment group.


Asunto(s)
Atención Ambulatoria , Hospitalización , Cuidados Paliativos , Terapia Cognitivo-Conductual , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
Br J Pharmacol ; 52(4): 499-507, 1974 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-4455326

RESUMEN

1 In order to establish the origin of the increased efflux of radioactivity caused by electrical stimulation of cerebral cortical slices which had been incubated with [(3)H]-choline, labelled choline and acetylcholine (ACh) collected by superfusion were separated by gold precipitation.2 In the presence of physostigmine electrical stimulation (1 Hz, 10 min) increased the release of only [(3)H]-ACh which was greatly enhanced by the addition of atropine.3 Continuous stimulation in the presence of physostigmine resulted in an evoked release of [(3)H]-ACh which declined asymptotically. This evoked release appeared to follow first-order kinetics with a rate constant which remained stable over the course of prolonged stimulation.4 The rate constant for the evoked release of [(3)H]-ACh with 1 Hz stimulation was three times greater in the presence of physostigmine and atropine than in the presence of physostigmine alone, while the size of the store from which [(3)H]-ACh was released was nearly identical under these two conditions.5 In the absence of physostigmine and atropine, stimulation caused the appearance of only [(3)H]-choline in the samples.6 Reduction of [(3)H]-ACh stores before the application of physostigmine resulted in a reduced evoked release of total radioactivity, both in the absence or presence of physostigmine and atropine, and decreased the evoked release of [(3)H]-ACh without affecting the release of [(3)H]-choline.7 Results suggest that electrical stimulation of cortical slices which had been incubated with [(3)H]-choline causes the release of only [(3)H]-ACh, both in the presence or absence of an anticholinesterase. The evoked increase in the efflux of total radioactivity is therefore a good measure of the release of [(3)H]-ACh.


Asunto(s)
Acetilcolina/metabolismo , Corteza Cerebral/metabolismo , Colina/metabolismo , Animales , Atropina/farmacología , Corteza Cerebral/fisiología , Inhibidores de la Colinesterasa/farmacología , Estimulación Eléctrica , Técnicas In Vitro , Fisostigmina/farmacología , Ratas , Factores de Tiempo
17.
Surgery ; 85(3): 263-7, 1979 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-424996

RESUMEN

Aortic trauma mainly involves the thoracic aorta (95%), while the abdominal aorta is infrequently involved (5%). Of growing interest is the role of seat belts in abdominal aortic injuries. Although seat belts are known to cause injuries to the abdominal viscera, they rarely produce aortic trauma. We report here an acute dissection with thrombosis of the abdominal aorta leading to complete peripheral occlusion as a result of lap-type seat belt injury. The two previously reported cases of similar injuries which resulted in incomplete occlusion are reviewed. A hypothesis for the causal mechanism of these injuries is described. The authors also stress careful follow-up of all patients with seat belt injuries since other intra-abdominal vascular injuries may be present.


Asunto(s)
Aorta Abdominal/lesiones , Enfermedades de la Aorta/etiología , Cinturones de Seguridad/efectos adversos , Trombosis/etiología , Heridas no Penetrantes , Accidentes de Tránsito , Adulto , Anciano , Fenómenos Biomecánicos , Desaceleración , Femenino , Humanos , Masculino
18.
Nutrition ; 16(4): 255-9, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10758359

RESUMEN

Nutritional management and dietary recommendations in patients with cystic fibrosis (CF) have changed considerably over the past 10-15 y. The nutritional status of adult CF patients was assessed in a clinical survey before these changes in nutritional management. The aim of the study was to assess the current nutritional status of the CF population and compare the results with those of the previous study. Forty-three (24 male, 19 female) subjects participated in this study. Subjects' height, weight, mid-upper-arm circumference, and skinfolds at four sites were measured. Nutritional intake was measured by using a 7-d food intake diary including documentation of supplements taken. Compared with the 1983 study, the incidence of malnutrition, as indicated by a body mass index of less than 20, has decreased from 62% to 9%. Furthermore, there have been significant improvements in the weight, height, and body mass index of both males (P < 0.001) and females (P < 0.04). Individuals with CF are no longer subject to growth arrest, as their mean height is now comparable to the Australian average. Mid-upper-arm circumference (P < 0.0001), triceps skinfold (P < 0.0001), and percentage of body fat (P < 0.05) of males and females have also significantly increased. The fat intake (P < 0.02) of females and males and energy intake (P < 0.03) of females have increased significantly, and the mean energy intake of subjects has exceeded the recommended 120% of the recommended daily intake. A significant number of patients in the present study receive dietary oral and/or enteral supplements. Multiple linear regression analysis indicated that nutritional management was principally responsible for improvements in nutritional status. The findings suggest that there has been a significant improvement in the nutritional status of the adult CF population, which may be due primarily to changes in nutritional management.


Asunto(s)
Composición Corporal , Fibrosis Quística/fisiopatología , Ingestión de Alimentos , Estado Nutricional , Adulto , Antropometría , Fibrosis Quística/dietoterapia , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Grosor de los Pliegues Cutáneos , Encuestas y Cuestionarios
19.
Disabil Rehabil ; 16(1): 26-34, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8136507

RESUMEN

This study examined changes in employment status and quality of work in 109 chronic pain patients who underwent a cognitive-behavioural pain management course; 68% of patients were female, mean age was 45 years, mean pain chronicity 10.7 years, 70% had spinal pain, and mean impairment on the Sickness Impact Profile was 26%. Twenty-six per cent of patients were employed at pre-treatment; the remaining 74% had been unemployed for 4.3 years on average. Measures of work status and quality, mood, pain, self-efficacy and walking performance were taken before admission, and at 1-, 6-, and 12-month follow-ups. Among employed patients quality of work scores improved by 35% from pre- to post-treatment (p < 0.01). Thirty per cent of previously unemployed patients returned to work during the 1-year follow-up, although employment status fluctuated greatly during this period. Non-workers were generally more impaired than workers on most measures, but the same measures did not differentiate between those who successfully returned to work and those who remained unemployed.


Asunto(s)
Empleo , Dolor/rehabilitación , Trabajo , Afecto , Terapia Conductista , Enfermedad Crónica , Estudios de Cohortes , Depresión , Femenino , Humanos , Locomoción , Masculino , Persona de Mediana Edad , Dolor/psicología , Terapia por Relajación
20.
J R Soc Med ; 79(10): 581-3, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3783546

RESUMEN

Gross metal poisoning as a causative factor in mental handicap is now relatively rare although historically it was important. Currently attention is being focused on the importance of chronic metal poisoning, there being much debate on, for instance, the possible effects of low levels of lead on intelligence in childhood. This paper examines the levels of a number of metals, both toxic and essential, in two groups of agitated patients in a long-stay psychiatric hospital in the UK. The two groups examined comprise 'hyperactive' mentally handicapped children and senile dementia patients, all of whom showed moderate to severe agitation. Blood and hair tissue were used to assess the body status of a number of metals and the results were compared with controls matched as closely as possible and from a similar hospital environment. The most significant findings are the raised levels of aluminium in the agitated senile dementia patients and the low levels of zinc and raised levels of lead in the hyperactive children.


Asunto(s)
Demencia/metabolismo , Hipercinesia/metabolismo , Discapacidad Intelectual/metabolismo , Oligoelementos/análisis , Niño , Demencia/sangre , Cabello/análisis , Humanos , Hipercinesia/sangre , Discapacidad Intelectual/sangre , Oligoelementos/sangre
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