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1.
Phys Rev Lett ; 130(24): 242301, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37390421

RESUMEN

The elliptic (v_{2}) and triangular (v_{3}) azimuthal anisotropy coefficients in central ^{3}He+Au, d+Au, and p+Au collisions at sqrt[s_{NN}]=200 GeV are measured as a function of transverse momentum (p_{T}) at midrapidity (|η|<0.9), via the azimuthal angular correlation between two particles both at |η|<0.9. While the v_{2}(p_{T}) values depend on the colliding systems, the v_{3}(p_{T}) values are system independent within the uncertainties, suggesting an influence on eccentricity from subnucleonic fluctuations in these small-sized systems. These results also provide stringent constraints for the hydrodynamic modeling of these systems.


Asunto(s)
Hidrodinámica , Masculino , Humanos , Anisotropía , Movimiento (Física)
2.
Phys Rev Lett ; 130(21): 212301, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37295104

RESUMEN

We report here the first observation of directed flow (v_{1}) of the hypernuclei _{Λ}^{3}H and _{Λ}^{4}H in mid-central Au+Au collisions at sqrt[s_{NN}]=3 GeV at RHIC. These data are taken as part of the beam energy scan program carried out by the STAR experiment. From 165×10^{6} events in 5%-40% centrality, about 8400 _{Λ}^{3}H and 5200 _{Λ}^{4}H candidates are reconstructed through two- and three-body decay channels. We observe that these hypernuclei exhibit significant directed flow. Comparing to that of light nuclei, it is found that the midrapidity v_{1} slopes of _{Λ}^{3}H and _{Λ}^{4}H follow baryon number scaling, implying that the coalescence is the dominant mechanism for these hypernuclei production in the 3 GeV Au+Au collisions.

3.
Phys Rev Lett ; 130(11): 112301, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-37001106

RESUMEN

We report on measurements of sequential ϒ suppression in Au+Au collisions at sqrt[s_{NN}]=200 GeV with the STAR detector at the Relativistic Heavy Ion Collider (RHIC) through both the dielectron and dimuon decay channels. In the 0%-60% centrality class, the nuclear modification factors (R_{AA}), which quantify the level of yield suppression in heavy-ion collisions compared to p+p collisions, for ϒ(1S) and ϒ(2S) are 0.40±0.03(stat)±0.03(sys)±0.09(norm) and 0.26±0.08(stat)±0.02(sys)±0.06(norm), respectively, while the upper limit of the ϒ(3S) R_{AA} is 0.17 at a 95% confidence level. This provides experimental evidence that the ϒ(3S) is significantly more suppressed than the ϒ(1S) at RHIC. The level of suppression for ϒ(1S) is comparable to that observed at the much higher collision energy at the Large Hadron Collider. These results point to the creation of a medium at RHIC whose temperature is sufficiently high to strongly suppress excited ϒ states.

4.
Phys Rev Lett ; 130(8): 082301, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36898098

RESUMEN

We report the beam energy and collision centrality dependence of fifth and sixth order cumulants (C_{5}, C_{6}) and factorial cumulants (κ_{5}, κ_{6}) of net-proton and proton number distributions, from center-of-mass energy (sqrt[s_{NN}]) 3 GeV to 200 GeV Au+Au collisions at RHIC. Cumulant ratios of net-proton (taken as proxy for net-baryon) distributions generally follow the hierarchy expected from QCD thermodynamics, except for the case of collisions at 3 GeV. The measured values of C_{6}/C_{2} for 0%-40% centrality collisions show progressively negative trend with decreasing energy, while it is positive for the lowest energy studied. These observed negative signs are consistent with QCD calculations (for baryon chemical potential, µ_{B}≤110 MeV) which contains the crossover transition range. In addition, for energies above 7.7 GeV, the measured proton κ_{n}, within uncertainties, does not support the two-component (Poisson+binomial) shape of proton number distributions that would be expected from a first-order phase transition. Taken in combination, the hyperorder proton number fluctuations suggest that the structure of QCD matter at high baryon density, µ_{B}∼750 MeV at sqrt[s_{NN}]=3 GeV is starkly different from those at vanishing µ_{B}∼24 MeV at sqrt[s_{NN}]=200 GeV and higher collision energies.

5.
Phys Rev Lett ; 131(20): 202301, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-38039468

RESUMEN

The polarization of Λ and Λ[over ¯] hyperons along the beam direction has been measured relative to the second and third harmonic event planes in isobar Ru+Ru and Zr+Zr collisions at sqrt[s_{NN}]=200 GeV. This is the first experimental evidence of the hyperon polarization by the triangular flow originating from the initial density fluctuations. The amplitudes of the sine modulation for the second and third harmonic results are comparable in magnitude, increase from central to peripheral collisions, and show a mild p_{T} dependence. The azimuthal angle dependence of the polarization follows the vorticity pattern expected due to elliptic and triangular anisotropic flow, and qualitatively disagrees with most hydrodynamic model calculations based on thermal vorticity and shear induced contributions. The model results based on one of existing implementations of the shear contribution lead to a correct azimuthal angle dependence, but predict centrality and p_{T} dependence that still disagree with experimental measurements. Thus, our results provide stringent constraints on the thermal vorticity and shear-induced contributions to hyperon polarization. Comparison to previous measurements at RHIC and the LHC for the second-order harmonic results shows little dependence on the collision system size and collision energy.

6.
Phys Rev Lett ; 130(20): 202301, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37267557

RESUMEN

We report the triton (t) production in midrapidity (|y|<0.5) Au+Au collisions at sqrt[s_{NN}]=7.7-200 GeV measured by the STAR experiment from the first phase of the beam energy scan at the Relativistic Heavy Ion Collider. The nuclear compound yield ratio (N_{t}×N_{p}/N_{d}^{2}), which is predicted to be sensitive to the fluctuation of local neutron density, is observed to decrease monotonically with increasing charged-particle multiplicity (dN_{ch}/dη) and follows a scaling behavior. The dN_{ch}/dη dependence of the yield ratio is compared to calculations from coalescence and thermal models. Enhancements in the yield ratios relative to the coalescence baseline are observed in the 0%-10% most central collisions at 19.6 and 27 GeV, with a significance of 2.3σ and 3.4σ, respectively, giving a combined significance of 4.1σ. The enhancements are not observed in peripheral collisions or model calculations without critical fluctuation, and decreases with a smaller p_{T} acceptance. The physics implications of these results on the QCD phase structure and the production mechanism of light nuclei in heavy-ion collisions are discussed.

7.
Diabetes Care ; 13(7): 776-84, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2201500

RESUMEN

Cyclosporin and other immunosuppressive agents have been proposed as a preventive treatment against the development of insulin-dependent diabetes mellitus (IDDM) in relatives at increased risk for the disease, based on the understanding that its etiology is an ongoing process of autoimmune beta-cell destruction. We used an epidemiological approach to evaluate several recent trials of cyclosporin in newly diagnosed IDDM patients to determine the degree of benefit that is to be expected. We assessed these and other studies to estimate the potential adverse effects of such treatment, were it to be used in the future, either in newly diagnosed subjects or healthy high-risk relatives. Standard sample-size calculations were used to quantify the number of study subjects necessary to allow adequate statistical power to test the positive and negative effects of a future treatment (alpha = 0.05, beta = 0.20). The estimates were based on the data available from published studies of cyclosporin treatment. The importance of conducting an adequate trial of such a therapy, both from an ethical and a practical viewpoint, is discussed. Five small immunosuppression trials were evaluated. Remission rates in treated subjects exceeded those in control subjects by 15-59%. Variability in defining remission may account for the differences in rates across the studies. Estimates of the major beneficial and adverse effects of cyclosporin were derived from these trials and studies of patients who have undergone long-term immunosuppression. Indicators of kidney damage associated with cyclosporin treatment were reported in 5-47% of treated subjects.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Ciclosporinas/uso terapéutico , Diabetes Mellitus Tipo 1/prevención & control , Ensayos Clínicos como Asunto , Ciclosporinas/efectos adversos , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/genética , Humanos , Factores de Riesgo
8.
Endocrinology ; 135(6): 2386-91, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7988421

RESUMEN

Insulin was administered to rats via nosedrops in the presence or absence of various alkylglycosides; systemic insulin absorption was measured as a fall in blood D-glucose concentration in animals made hyperglycemic by xylazine/ketamine anesthesia. Nosedrops (0.04 ml) containing alkylglycosides or regular porcine insulin alone were without effect. Nosedrops containing both a small amount of alkylglycoside (0.03-0.50%) and insulin (2 U regular porcine) caused a rapid decrease in blood D-glucose levels and a concomitant increase in serum immunoreactive insulin levels. The maximal hypoglycemic response was observed between 60 and 120 min after delivery of nosedrops. Decylmaltoside was less effective at enhancing systemic insulin absorption than dodecylmaltoside, tridecylmaltoside, or tetradecylmaltoside, whereas octylmaltoside was totally ineffective. Dodecylsucrose, a compound which differs from dodecylmaltoside only in one carbohydrate residue, had a similar effect on blood D-glucose values when it was included in the nosedrop formulation with insulin. Decylsucrose was considerably less potent than dodecylsucrose at enhancing systemic absorption of insulin. Nonylglucoside was effective at promoting insulin absorption from nosedrops only when used at higher doses (0.25-0.50%), whereas heptylglucoside and hexylglucoside were ineffective. These results indicated that nosedrops containing insulin plus an extremely low concentration (0.03%) of an absorption-enhancing agent such as tetradecylmaltoside can be used to lower blood D-glucose values.


Asunto(s)
Composición de Medicamentos , Insulina/administración & dosificación , Absorción/efectos de los fármacos , Administración Intranasal , Animales , Relación Dosis-Respuesta a Droga , Glicósidos/farmacología , Insulina/farmacocinética , Masculino , Ratas , Ratas Sprague-Dawley
9.
Am J Clin Nutr ; 49(4): 658-66, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2929488

RESUMEN

This study examined the hypothesis that the glucose component of food and not the total carbohydrate is the major determinant of the glycemic response in patients with insulin-dependent diabetes mellitus. Patients were given glucose alone, fructose alone, glucose + fructose, lactose, and glucose + fat + protein. Fructose given alone increased the blood glucose almost as much as a similar amount of glucose (78% of the glucose-alone area, p less than 0.05). However, the same amount of fructose given with glucose produced no greater glycemic response than did glucose alone (108%). Similarly, galactose contributed only slightly to the glycemic response when given as lactose (122%, p less than 0.01) whereas protein and fat had no additional glycemic effect (101%). To test the above hypothesis in natural foods, patients were fed an amount of bread (high glycemic index) or apple (low glycemic index) that contained 25 g glucose. Both challenges produced glycemic responses very similar to 25 g purified glucose.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 1/sangre , Carbohidratos de la Dieta/administración & dosificación , Alimentos , Adulto , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Femenino , Fructosa/administración & dosificación , Glucosa/administración & dosificación , Humanos , Lactosa/administración & dosificación , Masculino , Persona de Mediana Edad
10.
Science ; 191(4228): 768-72, 1976 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-17754174
11.
Am J Manag Care ; 3(2): 253-8, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10169259

RESUMEN

Triage guidelines are needed to help in the decision process of intensive care unit (ICU) versus non-ICU admission for patients with diabetic ketoacidosis (DKA). Pediatric risk of mortality (PRISM) scores have long been used to assess mortality risk. This study assess the usefulness of the traditional PRISM score and adaptation of that score (PRISM-ED, which uses presentation data only) in predicting hospital stay in pediatric patients with DKA. PRISM and PRISM-ED were tested for correlation with length of stay and length of ICU stay. A medical record review was conducted for patients admitted to The Children's Hospital of Alabama with DKA during an 18-month period (n = 79). Two scores were calculated for each study entrant: PRISM using the worst recorded values over the first 24 hours and PRISM-ED using arrival values. Median scores, median test, and Spearman rank correlations were determined for both tests. Median PRISM scores were PRISM = 11 and PRISM-ED = 12; Median PRISM and PRISM-ED scores for patients admitted to the ICU were less than median scores among floor-admitted patients: [table: see text] Spearman rank correlations were significant for both scores versus total stay: PRISM, rs = 0.29; P = 0.009; PRISM-ED, rs = 0.60, P < 0.001. Also, correlations were significant for both scores versus ICU stay: PRISM rs = 0.22, P = 0.05; PRISM-ED, rs = 0.41, P < 0.001. Triage guidelines for ICU versus floor admission for DKA patients could have significant economic impact (mean ICU charge = $11,417; mean charge for floor admission = $4,447). PRISM scores may be an important variable to include in a multiple regression model used to predict the need for ICU monitoring.


Asunto(s)
Cetoacidosis Diabética/clasificación , Cetoacidosis Diabética/terapia , Guías como Asunto , Unidades de Cuidado Intensivo Pediátrico/estadística & datos numéricos , Índice de Severidad de la Enfermedad , Triaje/normas , Adolescente , Alabama , Niño , Preescolar , Cetoacidosis Diabética/fisiopatología , Servicio de Urgencia en Hospital/normas , Femenino , Humanos , Unidades de Cuidado Intensivo Pediátrico/economía , Masculino , Programas Controlados de Atención en Salud/economía , Admisión del Paciente/economía , Estudios Retrospectivos , Revisión de Utilización de Recursos
12.
Endocr Pract ; 1(5): 318-9, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-15251575

RESUMEN

Diabetes insipidus is associated with histiocytosis X in approximately 50% of cases with multiple lesions that involve both intracranial and extracranial structures. Although approximately 8% of cases of diabetes insipidus in children are caused by involvement of the hypothalamus or pituitary infundibulum (or both) by histiocytosis X, diabetes insipidus can be the initial manifestation in many disorders most commonly, intracranial neoplasms. Herein we report a case of isolated histiocytosis X of the pituitary gland in a child for whom medical assistance was sought because of symptoms of diabetes insipidus.

13.
J Dev Behav Pediatr ; 19(1): 31-7, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9524303

RESUMEN

Adolescents' health attitudes and adherence to treatment for insulin-dependent diabetes mellitus (IDDM) were evaluated using the protection motivation theory (PMT). We expected cognitive appraisals of adherence (self-efficacy for treatment management, response efficacy of treatment, response costs of adherence) to be more influential for adherence than appraisals of nonadherence (rewards of nonadherence, perceptions of the risks of nonadherence, perceived severity of the risks). Adolescents (N = 101) with IDDM completed self-report measures of treatment adherence and of the PMT variables. Hierarchical regression analyses revealed that cognitions concerning adherence explained a statistically significant proportion of the variance in treatment adherence (sr2 = .17). Response costs of adherence produced the strongest correlations with overall adherence and with three of the four individual components of IDDM treatment (insulin injections, blood glucose monitoring, diet). The findings suggest that persuasive health communications might focus on appraisals of adherence rather than on risks of nonadherence.


Asunto(s)
Actitud Frente a la Salud , Diabetes Mellitus Tipo 1/psicología , Motivación , Cooperación del Paciente/psicología , Adolescente , Acampada , Niño , Diabetes Mellitus Tipo 1/rehabilitación , Humanos , Control Interno-Externo , Educación del Paciente como Asunto , Comunicación Persuasiva , Relaciones Médico-Paciente , Autocuidado/psicología , Autoimagen
14.
J Ky Med Assoc ; 93(5): 203-10, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7608636

RESUMEN

Dysphagia, a disorder of swallowing, is commonly associated with neurological and neuromuscular disorders. Damage to the sensation or muscles of the swallowing mechanism leads to unsafe oral motor or pharyngeal movement patterns, placing a patient at risk for development of aspiration pneumonia. At present, multidisciplinary Dysphagia Teams are being used to improve the diagnosis and treatment of swallowing disorders. A survey including all 112 hospitals in the Commonwealth of Kentucky indicates 33 (29%) presently have such a team, while 42 (38%) offer outpatient dysphagia services. In addition, 56 (50%) of the hospitals indicate they perform modified barium swallows which is an essential test for diagnosing and treating dysphagia. An example of how a Dysphagia Team works in one Kentucky rehabilitation hospital is presented to illustrate how to provide early diagnosis and treatment of these problems.


Asunto(s)
Trastornos de Deglución/rehabilitación , Grupo de Atención al Paciente , Sulfato de Bario , Terapia Combinada , Trastornos de Deglución/diagnóstico por imagen , Trastornos de Deglución/etiología , Diagnóstico Diferencial , Humanos , Kentucky , Radiografía
15.
Tenn Med ; 92(10): 382-4, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10513242

RESUMEN

Subatmospheric pressure application to acute and chronic wounds has been shown to increase local wound blood flow, increase the rate of formation of granulation tissue, and enhance bacterial clearance. The mechanical forces applied to the wound enhance the rate of granulation tissue formation by the increase intracellular messengers regulating protein production and turnover. This method of wound care is particularly useful for larger wounds that could not be readily closed by local methods, but may also be useful for chronic wounds in debilitated patients who may not be ideal surgical candidates. Further basic scientific research is needed to discern the exact mechanisms of action of subatmospheric pressure, and more clinical experience is needed to establish guidelines for its application. Further clinical studies with larger subject populations in a randomized prospective study would lend support to the utility of this wound management protocol.


Asunto(s)
Quemaduras por Electricidad/terapia , Cirugía Plástica/instrumentación , Cicatrización de Heridas , Adolescente , Presión Atmosférica , Traumatismos de la Espalda/terapia , Vendajes , Humanos , Masculino , Poliuretanos , Trasplante de Piel , Succión , Cicatrización de Heridas/fisiología
16.
J Back Musculoskelet Rehabil ; 4(2): 97-104, 1994 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24572021

RESUMEN

Many studies have been conducted to document the positive effects of exercise in the elderly. Initially, the focus was on the benefits of aerobic training, however, more recent studies have shown that the elderly respond to isometric, isotonic, and isokinetic programs. Strength and mobility are two of the key factors in assessing a person's risk for falling. Studies have shown that people who fall frequently have weaker ankle dorsiflexors and knee extensors than persons who do not fall. As a result, it has been speculated that exercise programs to strengthen these muscle groups will improve functional mobility and reduce the risk of falling. At present ongoing trials are trying to provide documentation to support this idea.

17.
J Back Musculoskelet Rehabil ; 15(1): 3-15, 2000 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22388334

RESUMEN

Manipulation, or manual medicine, is a highly utilized form of treatment for many types of musculoskeletal disorders, but there are many questions about the efficacy and safety of this form of treatment. This review of published trials for treatment of the upper body (cervical, thoracic, and upper limb) describes the patient groups that have been studied and may benefit from manual treatment, their outcomes, and their limitations. Cervical manipulation in particular has historically received criticism regarding safety, and the incidence of side effects, severe complications, and contraindications are discussed. The number of studies published for the upper body is small compared to the lumbar spine, and the lack of uniformity of the information still leaves the individual practitioner to decide if and when manipulation fits into his or her treatment algorithms for this region of the body.

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