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Recent attention has highlighted the importance of reducing sedentary time for maintaining health and quality of life. However, it is unclear how changing sedentary behavior may influence executive functions and self-regulatory strategy use, which are vital for the long-term maintenance of a health behavior regimen. The purpose of this cross-sectional study is to examine the estimated self-regulatory and executive functioning effects of substituting 30 min of sedentary behavior with 30 min of light activity, moderate-to-vigorous physical activity (MVPA), or sleep in a sample of older adults. This study reports baseline data collected from low-active healthy older adults (N = 247, mean age 65.4 ± 4.6 years) recruited to participate in a 6 month randomized controlled exercise trial examining the effects of various modes of exercise on brain health and function. Each participant completed assessments of physical activity self-regulatory strategy use (i.e., self-monitoring, goal-setting, social support, reinforcement, time management, and relapse prevention) and executive functioning. Physical activity and sedentary behaviors were measured using accelerometers during waking hours for seven consecutive days at each time point. Isotemporal substitution analyses were conducted to examine the effect on self-regulation and executive functioning should an individual substitute sedentary time with light activity, MVPA, or sleep. The substitution of sedentary time with both sleep and MVPA influenced both self-regulatory strategy use and executive functioning. Sleep was associated with greater self-monitoring (B = .23, p = .02), goal-setting (B = .32, p < .01), and social support (B = .18, p = .01) behaviors. Substitution of sedentary time with MVPA was associated with higher accuracy on 2-item (B = .03, p = .01) and 3-item (B = .02, p = .04) spatial working memory tasks, and with faster reaction times on single (B = -23.12, p = .03) and mixed-repeated task-switching blocks (B = -27.06, p = .04). Substitution of sedentary time with sleep was associated with marginally faster reaction time on mixed-repeated task-switching blocks (B = -12.20, p = .07) and faster reaction time on mixed-switch blocks (B = 17.21, p = .05), as well as reduced global reaction time switch cost (B = -16.86, p = .01). Substitution for light intensity physical activity did not produce significant effects. By replacing sedentary time with sleep and MVPA, individuals may bolster several important domains of self-regulatory behavior and executive functioning. This has important implications for the design of long-lasting health behavior interventions. Trial Registration clinicaltrials.gov identifier NCT00438347.
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Función Ejecutiva/fisiología , Ejercicio Físico/psicología , Conductas Relacionadas con la Salud , Conducta Sedentaria , Autocontrol , Sueño/fisiología , Anciano , Estudios Transversales , Ejercicio Físico/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Calidad de Vida , Factores de TiempoRESUMEN
Following the early prediction of the skyrmion lattice (SkL)--a periodic array of spin vortices--it has been observed recently in various magnetic crystals mostly with chiral structure. Although non-chiral but polar crystals with Cnv symmetry were identified as ideal SkL hosts in pioneering theoretical studies, this archetype of SkL has remained experimentally unexplored. Here, we report the discovery of a SkL in the polar magnetic semiconductor GaV4S8 with rhombohedral (C3v) symmetry and easy axis anisotropy. The SkL exists over an unusually broad temperature range compared with other bulk crystals and the orientation of the vortices is not controlled by the external magnetic field, but instead confined to the magnetic easy axis. Supporting theory attributes these unique features to a new Néel-type of SkL describable as a superposition of spin cycloids in contrast to the Bloch-type SkL in chiral magnets described in terms of spin helices.
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PURPOSE: Using data from the National Health Interview Survey (NHIS), this study examined the odds of functional limitations across nine domains by cancer status (with vs. without cancer history) and age group (18-44, 45-64, 65 + years). METHODS: Participants were 151,509 adults in the 2014-2018 NHIS. Functional limitations included self-reported difficulty conducting nine activities. Data were analyzed using age-stratified multivariate logistic regression (no limitation vs. limited in any way; minor limitation vs. major limitation) and are reported as covariate-adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs). To gather insight on the influence of cancer, compared to aging without a history of cancer, on functional limitations, we also conducted exploratory regression analyses comparing all cancer by age groups to 18-44 year-olds without a cancer history. RESULTS: Cancer survivors (n = 12,518) were more likely to report a limitation than adults without cancer (n = 138,991). Age-stratified ORs for 1 + limitation were 2.75 (95% CI 1.98, 3.81) among 18-44 year-olds, 2.42 (95% CI 2.00, 2.93) among 45-64 year-olds, and 1.59 (95% CI 1.39, 1.82) among 65 + year-olds. Cancer survivors were more likely to report major limitations across multiple domains, with age-stratified ORs ranging from 1.18 (65 + year-olds, stooping limitation) to 2.28 (18-44 year-old, sitting limitation). ORs from exploratory analyses were lowest among 45-64 year-old adults without a cancer history (2.69-4.42) and highest among older adult cancer survivors (3.42-14.73). CONCLUSIONS: Cancer was associated with limitations across age groups, with the highest age-stratified ORs observed among younger adults and for mobility and lower-extremity limitations. Stronger efforts to assess limitations as part of routine care and implement targeted interventions to address limitations are needed. IMPLICATIONS FOR CANCER SURVIVORS: Functional limitations have been linked with poorer aging trajectories and lower quality of life in cancer and non-cancer populations. Routine screening to identify and discuss functional limitations with cancer patients may help reduce the burden of such limitations on survivors.
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The magnetocrystalline anisotropy of GdRh2Si2 is examined in detail via the electron spin resonance (ESR) of its well-localised Gd3+ moments. Below T N = 107 K, long range magnetic order sets in with ferromagnetic layers in the (aa)-plane stacked antiferromagnetically along the c-axis of the tetragonal structure. Interestingly, the easy-plane anisotropy allows for the observation of antiferromagnetic resonance at X- and Q-band microwave frequencies. In addition to the easy-plane anisotropy we have also quantified the weaker fourfold anisotropy within the easy plane. The obtained resonance fields are modelled in terms of eigenoscillations of the two antiferromagnetically coupled sublattices. Conversely, this model provides plots of the eigenfrequencies as a function of field and the specific anisotropy constants. Such calculations have rarely been done. Therefore our analysis is prototypical for other systems with fourfold in-plane anisotropy. It is demonstrated that the experimental in-plane ESR data may be crucial for a precise knowledge of the out-of-plane anisotropy.
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Using ferromagnetic resonance spectroscopy at 34 GHz we explored the magnetic anisotropy of single-crystalline GaV4S8 in the field-polarized magnetic state. We describe the data in terms of an easy-axis type uniaxial anisotropy with an anisotropy constant [Formula: see text] erg cm-3 at 2 K, corresponding to a relative exchange anisotropy [Formula: see text]%, and about [Formula: see text]erg cm-3 near 11 K, i.e. at temperatures where the skyrmion-lattice phase was recently discovered. The relatively large value of K 1 explains the confinement of the skyrmion tubes to the [Formula: see text] easy axes. A distinct set of resonances in the spectra is attributed to the co-existence of different rhombohedral domains. Complementary broadband spectroscopy demonstrates that non-collinear spin states may sensitively be detected by electron spin resonance techniques.
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The skyrmion lattice state (SkL), a crystal built of mesoscopic spin vortices, gains its stability via thermal fluctuations in all bulk skyrmion host materials known to date. Therefore, its existence is limited to a narrow temperature region below the paramagnetic state. This stability range can drastically increase in systems with restricted geometries, such as thin films, interfaces and nanowires. Thermal quenching can also promote the SkL as a metastable state over extended temperature ranges. Here, we demonstrate more generally that a proper choice of material parameters alone guarantees the thermodynamic stability of the SkL over the full temperature range below the paramagnetic state down to zero kelvin. We found that GaV4Se8, a polar magnet with easy-plane anisotropy, hosts a robust Néel-type SkL even in its ground state. Our supporting theory confirms that polar magnets with weak uniaxial anisotropy are ideal candidates to realize SkLs with wide stability ranges.
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A joint study of the rotational dynamics and free volume in amorphous 1-propanol (1-PrOH) as a prototypical monohydroxy alcohol by electron spin resonance (ESR) or positron annihilation lifetime spectroscopy (PALS), respectively, is reported. The dynamic parameters of the molecular spin probe 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and the annihilation ones of the atomic ortho-positronium (o-Ps) probe as a function of temperature are compared. A number of coincidences between various effects in the ESR and PALS responses at the corresponding characteristic ESR and PALS temperatures were found suggesting a common origin of the underlying dynamic processes that were identified using viscosity (VISC) in terms of the two-order parameter (TOP) model and broadband dielectric spectroscopy (BDS) data.
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INTRODUCTION: In the present study, we examined the influence of a home-based, DVD-delivered exercise intervention on daily sedentary time and breaks in sedentary time in older adults. METHODS: Between 2010 and 2012, older adults (i.e., aged 65 or older) residing in Illinois (N = 307) were randomized into a 6-month home-based, DVD-delivered exercise program (i.e., FlexToBa; FTB) or a waitlist control. Participants completed measurements prior to the first week (baseline), following the intervention period (month 6), and after a 6 month no-contact follow-up (month 12). Sedentary behavior was measured objectively using accelerometers for 7 consecutive days at each time point. Differences in daily sedentary time and breaks between groups and across the three time points were examined using mixed-factor analysis of variance (mixed ANOVA) and analysis of covariance (ANCOVA). RESULTS: Mixed ANOVA models revealed that daily minutes of sedentary time did not differ by group or time. The FTB condition, however, demonstrated a greater number of daily breaks in sedentary time relative to the control condition (p = .02). ANCOVA models revealed a non-significant effect favoring FTB at month 6, and a significant difference between groups at month 12 (p = .02). CONCLUSIONS: While overall sedentary time did not differ between groups, the DVD-delivered exercise intervention was effective for maintaining a greater number of breaks when compared with the control condition. Given the accumulating evidence emphasizing the importance of breaking up sedentary time, these findings have important implications for the design of future health behavior interventions.
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The purpose of the study was to evaluate the number of inappropriate admissions to a smaller city hospital and find possible alternatives. Physicians and surgeons from three units (abdominal surgery, internal medicine and orthopaedic surgery) together with general practitioners, doctors on homecall duty and health personnel from the region contributed to the study. In all 421 consecutive patients were included during a three-week period. The patients' median age was 60.5 years. It was found that at least 13.6% of all patients seemed to have been admitted for an inappropriate reason. According to the admitting doctor 3.4% of the patients were not ill at all. The investigation implies that one out of seven acute admissions could be replaced by alternatives such as immediate care in residential homes, more flexible contact to the outpatient's clinic, better access to geriatric evaluation and improved laboratory service. We conclude that acute admission to hospital can be replaced by other alternatives, thereby achieving greater efficiency and better economics.
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Servicio de Urgencia en Hospital/estadística & datos numéricos , Accesibilidad a los Servicios de Salud , Hospitales Municipales/estadística & datos numéricos , Admisión del Paciente/estadística & datos numéricos , Adulto , Anciano , Atención Ambulatoria/normas , Dinamarca , Servicio de Urgencia en Hospital/economía , Femenino , Hospitales Municipales/economía , Humanos , Masculino , Persona de Mediana Edad , Encuestas y CuestionariosAsunto(s)
Antagonistas Adrenérgicos beta/síntesis química , Antagonistas Adrenérgicos beta/farmacología , Animales , Técnicas In Vitro , Yeyuno/efectos de los fármacos , Métodos , Fenetilaminas/síntesis química , Fenetilaminas/farmacología , Propanolaminas/síntesis química , Propanolaminas/farmacología , ConejosAsunto(s)
Cateterismo Cardíaco/efectos adversos , Cuerpos Extraños/terapia , Corazón , Enfermedad Iatrogénica , Adulto , Preescolar , Femenino , Humanos , Masculino , Métodos , Persona de Mediana EdadRESUMEN
Both the uptake of C3-opsonized and of nonopsonized bakers' yeast is inhibited by 1 mM trypan blue. This effect may be explained by inactivation of the C3bi-receptor. But trypan blue also inhibited the uptake of other non-opsonized particles lacking specially binding domains for this receptor. - Suramin has antiphagocytic properties at 1 mM concentration which were explained by its anticomplementary activity. However, the uptake of nonopsonized particles is also inhibited by suramin. The importance of these effects for therapeutic utilization is discussed.
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Neutrófilos/efectos de los fármacos , Fagocitosis/efectos de los fármacos , Saccharomyces cerevisiae/inmunología , Suramina/efectos adversos , Azul de Tripano/efectos adversos , Animales , Cobayas , Neutrófilos/inmunología , Proteínas OpsoninasRESUMEN
Actomyosin preparations of the carotid arteries of cattle contain a soluble phosphatase activity, which can be removed from the contractile proteins by repeated washings. This enzyme activity is lowered by high ionic strength, potassium fluoride, zinc acetate, ammonium molybdate, and vanadate. Magnesium ions enhance the enzyme activity. The phosphatase activity shows a maximum between pH 5.5 and 6.0 and a plateau of pH 7-9. By means of gel filtration on Sepharose 6B the phosphate activity is separated into three peaks, which are characterized with respect to their inhibition by potassium fluoride, ammonium molybate, and vanadate and their dependence on pH.
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Fluoruros , Monoéster Fosfórico Hidrolasas/aislamiento & purificación , Compuestos de Potasio , Actomiosina/fisiología , Animales , Arterias Carótidas/enzimología , Bovinos , Precipitación Química , Magnesio/farmacología , Cloruro de Magnesio , Molibdeno/farmacología , Músculo Liso Vascular/enzimología , Monoéster Fosfórico Hidrolasas/antagonistas & inhibidores , Potasio/farmacología , Vanadatos , Vanadio/farmacologíaRESUMEN
The superprecipitation of actomyosin from the A. carotis of cattle is suppressed by a phosphatase containing protein fraction. This inhibition is compensated by ammonium molybdate, an inhibitor of phosphatase activity. The results are related to a phosphorylation-dephosphorylation cycle to realize the Ca-sensitivity of superprecipitation of the actomyosin.
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Actomiosina/metabolismo , Calcio/farmacología , Músculo Liso Vascular/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Animales , Arterias Carótidas/metabolismo , Bovinos , Molibdeno/farmacología , Fosforilación , Compuestos de Amonio Cuaternario/farmacologíaRESUMEN
The high affinity of granulocytes of guinea pig and man to glass surfaces is modified by serum. Native serum contains both an adherence-promoting activity, which is related to complement, and components which reduce the adhesiveness of granulocytes. These components are stable at 56 degrees C for 30 min and are tightly bound to the glass surface. beta-Lipoproteins are candidates for this adherence reducing ability of serum. Adherence promotion by native serum is mediated by coating the glass surface with C3b/C3bi. Human granulocytes from the peripheral blood adhered pig serum with C3b/C3bi to almost the same extent as in the presence of native serum, but on guinea pig granulocytes elicited in the peritoneal cavity, a cell surface metalloproteinase degraded the C3b/C3bi, thus reducing the adhesiveness of these cells. This proteinase was inhibited by MgEDTA, DTT, and 1,10-phenanthroline, whereby the high adhesiveness of granulocytes was restored to C3b/C3bi-coated glass.
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Granulocitos/fisiología , Cobayas/fisiología , Animales , Fenómenos Fisiológicos Sanguíneos , Adhesión Celular/efectos de los fármacos , Complemento C3b/metabolismo , Complemento C3b/fisiología , Vidrio , Humanos , Hidrazinas/farmacología , Metaloendopeptidasas/metabolismo , TemperaturaRESUMEN
A microsomal fraction was isolated from the media-intima of the bovine carotid artery; the preparation is a mixed fraction of membranal and mitochondrial debris, which is able to bind Ca-ions and to take them up in the presence of ATP. The Ca-uptake is activated within a pCa range from 7--5. The involvement of two different systems in the Ca-uptake is discussed. A Ca-stimulatable ATPase was demonstrated, whose relationship with a Ca-transport system could not be established, however. The substrate for Ca-uptake is MgATP; in addition, free Mg has a stimulating effect. The Na/Kratio has no influence on the Ca-uptake. The influence of the pH-value on the Ca-binding and Ca-uptake was studied. Phosphate increased the Ca-uptake, while oxalate did not. The investigated system is discussed as a model for the action of vaso-active drugs.
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Calcio/metabolismo , Arterias Carótidas/metabolismo , Microsomas/metabolismo , Adenosina Trifosfatasas/metabolismo , Animales , Transporte Biológico Activo/efectos de los fármacos , Bovinos , Cinética , Magnesio/farmacología , Microsomas/ultraestructuraRESUMEN
The study included 88 patients with sterile urine prior to transurethral prostatectomy. Forty-five received a preoperative dose of 2 g of cefotaxime (Claforan) and the remaining 43 were given 10 ml of 0.9% NaCl. The two groups did not differ in frequency of postoperative urinary infection (greater than 10(5) colonies per ml urine); 6 patients (13.3%) in the cefotaxime group had postoperative infections during hospital stay as compared to 8 patients (18.6%) in the control group (0.5 greater than p greater than 0.3). Those in the cefotaxime group who had infections were tested for resistance. They were all fully sensitive to cefotaxime except one, who was infected with enterococci. There was no growth of bacteria from either venous blood or bladder irrigating fluid taken during the operations. Nor were any serious complications observed in any of the patients. In view of the relatively low risk of infection and the few side effects of the infections that did occur, prophylactic treatment with an antibiotic is not indicated for transurethral prostatectomy in patients with sterile urine.
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Infecciones Bacterianas/prevención & control , Cefotaxima/uso terapéutico , Complicaciones Posoperatorias/prevención & control , Premedicación , Prostatectomía , Infecciones Urinarias/prevención & control , Anciano , Bacteriuria/tratamiento farmacológico , Evaluación de Medicamentos , Farmacorresistencia Microbiana , Humanos , Masculino , Persona de Mediana Edad , Distribución AleatoriaRESUMEN
Nitroprusside-sodium, nitroglycerol, and verapamil had no effect on the calcium uptake by microsomes from the carotid artery of cattle. Prenylamine reduced the passive binding and the active uptake and released already bound calcium. The basal Mg-dependendent ATPase and Ca-stimulatable Mg-ATPase were inhibited by prenylamine.
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Calcio/metabolismo , Arterias Carótidas/metabolismo , Microsomas/metabolismo , Relajantes Musculares Centrales/farmacología , Músculo Liso/efectos de los fármacos , Animales , Bovinos , Músculo Liso/metabolismo , Nitroglicerina/farmacología , Nitroprusiato/farmacología , Prenilamina/farmacología , Verapamilo/farmacologíaRESUMEN
1. The temporal relationship between the myocardial arteriovenous difference of plasma propranolol concentration and heart rate and left ventricular dp/dt maximum was examined for 30 min after intravenous administration of 10mg (0.04 mmol) dl-propranolol in nine patients with ischaemic heart disease. 2. Very large positive myocardial a.v. differences of propranolol within the first 5 min became negative after 5 min, indicating a rapid, avid uptake with subsequent release of propranolol from the heart. 3. The heart rate and left ventricular dp/dt maximum increased 1 min after propranolol administration and did not change after the fifth min of the observation period. 4. The data suggest that a large number of unspecific binding sites for propranolol are present in the heart in addition to the specific beta-receptors.