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1.
Phys Rev Lett ; 118(9): 092503, 2017 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-28306272

RESUMEN

Radioactive ^{136}Te has two valence protons and two valence neutrons outside of the ^{132}Sn double shell closure, providing a simple laboratory for exploring the emergence of collectivity and nucleon-nucleon interactions. Coulomb excitation of ^{136}Te on a titanium target was utilized to determine an extensive set of electromagnetic moments for the three lowest-lying states, including B(E2;0_{1}^{+}→2_{1}^{+}), Q(2_{1}^{+}), and g(2_{1}^{+}). The results indicate that the first-excited state, 2_{1}^{+}, composed of the simple 2p⊕2n system, is prolate deformed, and its wave function is dominated by excited valence neutron configurations, but not to the extent previously suggested. It is demonstrated that extreme sensitivity of g(2_{1}^{+}) to the proton and neutron contributions to the wave function provides unique insight into the nature of emerging collectivity, and g(2_{1}^{+}) was used to differentiate among several state-of-the-art theoretical calculations. Our results are best described by the most recent shell model calculations.

2.
Curr Atheroscler Rep ; 19(11): 47, 2017 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-29019063

RESUMEN

PURPOSE OF REVIEW: Our aim was to examine the current evidence behind prescribing statins to individuals over 65 years of age with emphasis on those older than 75. Individuals over 75 years of age may often have multiple comorbidities and take many medications. Additionally, they are often underrepresented in randomized controlled trials (RCTs) of statins in older populations. While results of RCTs demonstrate the benefit of statin therapy in both primary and secondary prevention patients, clinicians must more carefully consider adverse effects and drug-drug interactions before prescribing statin therapy as well as determining the intensity in older individuals. RECENT FINDINGS: Four primary prevention trials support statins for primary prevention following a clinician-patient risk discussion. Of these, JUPITER and HOPE-3 studied participants 70 years of age and over who derived benefit. However, in those over 85 years, available information is inadequate to guide decisions regarding statin therapy. Documented statin adverse effects include new onset diabetes, myopathy, and medication interactions. Although cognitive decline has been reported anecdotally, its incidence was comparable to placebo in two RCTs with validated cognitive evaluations. Concerns about significant liver and kidney injury with statins were not corroborated in RCTs. For most patients, the potential for reducing ASCVD risk outweighs possible adverse effects; however, in the elderly, the impact of drug treatment on cognition, musculoskeletal ability, and independence must be heavily weighed. Given the limited high quality evidence for primary prevention in individuals over 75 years of age, neither the ACC-AHA nor USPSTF cholesterol guidelines recommend statin therapy for primary prevention in this patient population. If prescribed, physician judgment and shared decision-making are crucial. To aid clinicians, imaging studies of subclinical atherosclerosis may improve specificity of statin therapy to prevent ASCVD in the elderly in primary prevention.


Asunto(s)
Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/prevención & control , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipercolesterolemia/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Prescripciones de Medicamentos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
3.
Phys Rev Lett ; 112(17): 172701, 2014 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-24836240

RESUMEN

Single-neutron states in (133)Sn and (209)Pb, which are analogous to single-electron states outside of closed atomic shells in alkali metals, were populated by the ((9)Be, (8)Be) one-neutron transfer reaction in inverse kinematics using particle-γ coincidence spectroscopy. In addition, the s(1/2) single-neutron hole-state candidate in (131)Sn was populated by ((9)Be, (10)Be). Doubly closed-shell (132)Sn (radioactive) and (208)Pb (stable) beams were used at sub-Coulomb barrier energies of 3 MeV per nucleon. Level energies, γ-ray transitions, absolute cross sections, spectroscopic factors, asymptotic normalization coefficients, and excited-state lifetimes are reported and compared with shell-model expectations. The results include a new transition and precise level energy for the 3p(1/2) candidate in (133)Sn, new absolute cross sections for the 1h(9/2) candidate in (133)Sn and 3s(1/2) candidate in (131)Sn, and new lifetimes for excited states in (133)Sn and (209)Pb. This is the first report on excited-state lifetimes of (133)Sn, which allow for a unique test of the nuclear shell model and (132)Sn double-shell closure.

4.
Phys Rev Lett ; 109(3): 032504, 2012 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-22861842

RESUMEN

The nucleus 49Sc, having a single f(7/2) proton outside doubly magic 48Ca (Z=20, N=28), is one of the very few isotopes which makes possible testing of the fundamental theory of nuclear magnetism. The magnetic moment has been measured by online ß NMR of nuclei oriented at milli-Kelvin temperatures to be (+)5.616(25) µ(N). The result is discussed in terms of a detailed theory of the structure of the magnetic moment operator, showing excellent agreement with calculated departure from the f(7/2) Schmidt limit extreme single-particle value. The measurement completes the sequence of moments of Sc isotopes with even numbers of f(7/2) neutrons: the first such isotopic chain between two major shells for which a full set of moment measurements exists. The result further completes the isotonic sequence of ground-state moments of nuclei with an odd number of f(7/2) protons coupled to a closed subshell of f(7/2) neutrons. Comparison with a recent shell-model calculation of the latter sequence is made.

5.
Phys Rev Lett ; 103(14): 142501, 2009 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-19905565

RESUMEN

We report the first confirmation of the predicted inversion between the pi2p3/2 and pi1f5/2 nuclear states in the nu(g)9/2 midshell. This was achieved at the ISOLDE facility, by using a combination of in-source laser spectroscopy and collinear laser spectroscopy on the ground states of 71,73,75Cu, which measured the nuclear spin and magnetic moments. The obtained values are mu(71Cu)=+2.2747(8)mu(N), mu(73Cu)=+1.7426(8)mu(N), and mu(75Cu)=+1.0062(13)mu(N) corresponding to spins I=3/2 for 71,73Cu and I=5/2 for 75Cu. The results are in fair agreement with large-scale shell-model calculations.

6.
J Clin Invest ; 64(2): 524-33, 1979 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-222811

RESUMEN

To investigate the gene-dosage effect in familial hypercholesterolemia (FH), metabolic studies were conducted in a group of well-characterized patients with either heterozygous (n = 7) or homozygous (n = 7) FH and the results were compared to those obtained in normal subjects (n = 6). The turnover of (125)I-labeled low-density lipoprotein (LDL) was measured in all of the normals, all but one of the FH heterozygotes, and in all of the homozygotes. Chemical cholesterol balance was performed simultaneously with the (125)I-LDL turnover in all seven of the homozygotes. With regard to (125)I-LDL turnover, FH homozygotes, who possess two doses of the mutant FH gene, exhibited a threefold increase in the rate of apoLDL synthesis while the fractional catabolic rate (FCR) for the apoprotein was only about one-third of normal. Heterozygotes, who have only one dose of the mutant FH gene, exhibited intermediate values for both parameters; that is, the FCR was two-thirds of normal and the apoLDL synthetic rate was 1.7-fold greater than normal. THE DATA INDICATE THAT THE SINGLE GENE DEFECT IN FH PRODUCES TWO DISTINCT ABNORMALITIES OF LDL METABOLISM: (a) an increase in the synthetic rate for apoLDL and (b) a decrease in the efficiency of apoLDL catabolism. Both defects are more severe in FH homozygotes than in heterozygotes. The FCR for apoLDL in the homozygotes appeared to be fixed at congruent with 17%/d whereas the plasma LDL level varied about twofold. These findings suggest that the twofold variation in plasma LDL levels observed in these seven patients is caused by variation in the plasma apoLDL synthetic rates. Consistent with this conclusion was the finding that the correlation between the plasma LDL level and the apoLDL synthetic rates in the seven FH homozygotes was 0.943. The rate of total body cholesterol synthesis determined by chemical cholesterol balance did not appear to clearly differ between normals and patients with either one or two mutant FH genes. Two of the youngest FH homozygotes exhibited cholesterol overproduction but the other five did not. No consistent abnormality of bile acid metabolism was observed in these patients. Because the daily plasma flux of cholesterol on LDL is about threefold greater than the amount of cholesterol produced per day, a significant amount of the cholesterol liberated from LDL degradation must be reused.


Asunto(s)
Heterocigoto , Homocigoto , Hipercolesterolemia/metabolismo , Lipoproteínas LDL/metabolismo , Adolescente , Adulto , Niño , Preescolar , Colesterol/sangre , Colesterol/metabolismo , Femenino , Humanos , Hipercolesterolemia/sangre , Hipercolesterolemia/genética , Cinética , Lipoproteínas HDL/sangre , Lipoproteínas LDL/sangre , Masculino , Persona de Mediana Edad , Triglicéridos/sangre
7.
Diabetes Care ; 2(4): 336-41, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-510128

RESUMEN

To evaluate the reliability of the tradional methods to assess short-term control of diabetes, 25 children with insulin-dependent diabetes were studied with a 24-h glucose profile in addition to the traditional assessment techniques. Patient compliance was elminated as much as possible from the experimental design. The correlation of the routine methods with the 24-h glucose profile was excellent, and a scoring system for control was empirically derived. The single method of assessment that correlated best with the overall control score was the traditional daily urine test. In 6 of the 25 subjects studied, relative hypoglycemia was observed, occurring asymptomatically at night, and was followed by a hyperglycemic rebound. Traditional assessment techniques did not detect this event. Five additional patients had symptomatic daytime hypoglycemia. We conclude that the traditional daily urine tests are adquate indicators of day-to-day control in most diabetic patients, given adquate compliance. Our data also suggest that asymptomatic nocturnal hypoglycemia occurs frequently in children with diabetes, although clinical proof is difficult in the absence of a 24-h glucose profile.


Asunto(s)
Diabetes Mellitus/prevención & control , Adolescente , Glucemia , Niño , Femenino , Glucosuria , Humanos , Masculino , Cooperación del Paciente
8.
Am J Med ; 101(4A): 4A6S-9S, 1996 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-8900331

RESUMEN

The clinical and economic impact of cardiovascular disease is tremendous. Of the four major cardiovascular diseases, coronary artery disease caused by atherosclerosis is the leading cause of death in the United States. It is also a major cause of morbidity. The cost of treating heart disease continues to spiral, from $128 billion in 1994 to an estimated $151 billion in 1996. Studies have shown that treating risk factors for coronary disease--e.g., cigarette smoking, physical inactivity, and elevated low-density-lipoprotein cholesterol and blood-pressure levels--can significantly reduce mortality and improve clinical outcomes. Studies have also shown that risk-factor reduction results in cost savings. Today's challenge is to effectively incorporate risk-reduction strategies into daily clinical practice and reduce the personal and societal burden of cardiovascular disease.


Asunto(s)
Enfermedad de la Arteria Coronaria , Enfermedad de la Arteria Coronaria/economía , Enfermedad de la Arteria Coronaria/mortalidad , Enfermedad de la Arteria Coronaria/prevención & control , Análisis Costo-Beneficio , Humanos , Tasa de Supervivencia
9.
Am J Med ; 101(4A): 4A40S-48S; discussion 48S-49S, 1996 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-8900336

RESUMEN

Diet and drug therapy are two of the principal approaches to lipid management. The aim of both is to reduce low-density-lipoprotein (LDL) cholesterol to goal levels established by the National Cholesterol Education Program Expert Panel in its second report, based on a patient's short-term risk of a coronary event. In prescribing diet therapy, it is important to determine patients' willingness to initiate and adhere to dietary modifications, their skill at reading nutritional labels, adapting recipes, and ordering "heart-healthy" foods when eating out. Diet therapy should be directed at modifying dietary factors known to adversely influence blood cholesterol-saturated fats, cholesterol, and obesity. Diet therapy (with exercise) is not always adequate. High risk individuals with no overt coronary artery disease but with >/=2 risk factors, as well as patients with coronary artery disease, are potential candidates for drug therapy, depending on their LDL cholesterol levels. The "statins" are the drug of choice for patients with coronary disease and elevated LDL cholesterol or familial LDL-cholesterol abnormalities. These drugs increase high-density-lipoprotein (HDL) cholesterol and reduce LDL cholesterol, coronary artery disease, and total mortality. Bile acid resins lower LDL cholesterol and are often used to augment the effects of the statins and niacin. Niacin is particularly useful in the management of patients with combined hyperlipidemia and low HDL cholesterol levels. Gemfibrozil is effective in familial dysbetalipoproteinemia and is the drug of choice for patients with severely elevated serum triglycerides.


Asunto(s)
Hiperlipidemias/dietoterapia , Hiperlipidemias/tratamiento farmacológico , Dieta , Gemfibrozilo/uso terapéutico , Humanos , Niacina/uso terapéutico , Educación del Paciente como Asunto
10.
Endocrinol Metab Clin North Am ; 19(2): 321-44, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2162770

RESUMEN

This review has highlighted some of the experimental studies in animals and humans that have shown an important link between dietary change and atherosclerosis. This relationship was further supported by population studies showing a key role for saturated fat intake in the determination of serum cholesterol level and the prediction of CHD. Recent data linking dietary cholesterol independent of serum cholesterol level to the prediction of CHD were discussed as well. Various components of the diet and their effects on lipid and lipoproteins were reviewed. The chief factors in the diet which raise cholesterol and low-density lipoprotein cholesterol (LDL-c) are dietary cholesterol, saturated fat, and excess calories leading to obesity. Dietary factors useful in lowering cholesterol and low-density lipoprotein cholesterol include monounsaturated fats, polyunsaturated fats, and dietary fiber, which can be substituted for saturated fats. The usefulness of a special class of polyunsaturated oil, the omega-3 fatty acids, in both lowering triglyceride levels and preventing thrombosis was also discussed. Although alcohol raises the HDL-c level, it is not clear that its use offers protection against CHD, and its risks clearly outweigh its advantages in this regard. Regular aerobic exercise is recommended as a healthier alternative to raising high-density lipoprotein cholesterol. Also discussed was postprandial lipemia, which may prove to be another indicator of risk of CHD. Finally, the recent NCEP dietary guidelines were discussed along with practical suggestions as to their implementation.


Asunto(s)
Enfermedad Coronaria/etiología , Dieta , Lípidos/sangre , Animales , Colesterol en la Dieta/administración & dosificación , Enfermedad Coronaria/prevención & control , Grasas de la Dieta/administración & dosificación , Fibras de la Dieta/administración & dosificación , Etanol/efectos adversos , Humanos , Lipoproteínas/sangre
11.
Med Clin North Am ; 78(1): 117-41, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8283927

RESUMEN

Secondary causes of hyperlipidemia are important to recognize. In fact, hyperlipidemia may be a clue to the presence of an underlying systemic disorder. It may greatly heighten the risk of atherosclerosis with a raised LDL-c, triglyceride-rich lipoprotein excess, and increased lipoprotein(a) as well as lowered HDL-c. The search for secondary causes may provide a clue as to why patients with primary lipid disorders suddenly develop worsening lipid profiles. The point is a crucial one because some acquired causes of hyperlipidemia, such as alcohol, estrogens, steroids, or pregnancy, when superimposed on a primary familial form of hypertriglyceridemia can result in a saturated removal system and a buildup of chylomicrons, which can lead to life-threatening pancreatitis. A convenient way to remember secondary causes is to think of the four D's of diet, drugs, disorders of metabolism, and diseases. Although diets rich in saturated fats and cholesterol are a common cause of the mild hypercholesterolemia seen in our society, alcohol excess and weight gain can explain much of the tendency toward hypertriglyceridemia. Interestingly anorexia nervosa has long been associated with severe but reversible hypercholesterolemia. Several classes of drugs need to be considered as common causes of altered lipid profiles. Glucocorticoids and estrogens elevate triglycerides and raise levels of HDL-c. Anabolic steroids taken orally markedly reduce levels of HDL-c in contrast to injectable testosterone, which does not adversely affect the LDL-to-HDL ratio. Oral contraceptives affect atherosclerotic risk depending on the kind and doses of progestin/estrogen. In those with an underlying primary hypertriglyceridemia and associated obesity, estrogenic medications can depress triglyceride removal mechanisms, leading to the chylomicronemia syndrome and pancreatitis. Antihypertensives have variable effects on lipids and lipoproteins. Although short-term thiazide usage raises cholesterol, triglycerides, and LDL-c, long-term usage is not necessarily associated with significant alterations in lipid levels. Alpha blockers may cause an increase in HDL-c, whereas beta blockers raise triglycerides and lower HDL-c. Sympatholytics, angiotensin converting enzyme inhibitors, and calcium channel blockers are essentially lipid neutral. Retinoids can be associated with increased LDL-to-HDL ratios and occasionally striking elevations in triglycerides. Cyclosporine raises LDL-c and lipoprotein(a). Classes of drugs that may raise HDL-c include cimetidine, antiepileptic drugs, and tamoxifen, but the effect may be seen primarily in women. Hypothyroidism is the most common secondary cause of hyperlipidemia after dietary causes are considered. A thyroxine and TSH level should be obtained on all new cases of clinically important hyperlipidemia.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Hiperlipidemias/etiología , Humanos
12.
Med Clin North Am ; 84(1): 95-122, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10685130

RESUMEN

This article has considered a vast literature attesting to the efficacy of dietary intervention on risk factors and on vascular outcomes. Rather than rely solely on pharmacotherapy to improve risk factors and vascular outcomes, physicians, nurses, dietitians, pharmacists, and medical providers should emphasize the benefits of a well-balanced, nutritionally sound dietary program. It should be low in SFA; controlled in calories to avoid (or reduce) obesity; and rich in fruits, vegetables, whole-grain products, and good sources of protein. Emphasis on foods rich in n-3 fatty acids shows promise for reducing cardiovascular outcomes. Further studies using these and antioxidants are eagerly awaited.


Asunto(s)
Dieta con Restricción de Grasas , Dieta Reductora , Infarto del Miocardio/dietoterapia , Obesidad/dietoterapia , Humanos , Lípidos/sangre , Infarto del Miocardio/sangre , Infarto del Miocardio/etiología , Obesidad/sangre , Obesidad/complicaciones , Recurrencia , Factores de Riesgo , Resultado del Tratamiento
13.
Clin Cornerstone ; 1(1): 31-49, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-10682162

RESUMEN

In 1995, the latest year for which statistics are available, heart disease, cancer, and stroke continued to be the three leading causes of death in the United States. Notably, however, a wealth of experience has confirmed that hygienic interventions such as diet, exercise, weight loss, and smoking cessation can reduce the toll from heart disease while also reducing the morbidity and mortality associated with stroke and cancer. This chapter will describe the rationale for the primary prevention of coronary heart disease (CHD), review the basic concepts involved in cholesterol screening, and update the reader regarding key preventive measures, such as diet, exercise, and smoking cessation. Also highlighted will be recent clinical trial results suggesting the benefits of lipid-lowering drugs in "high-risk" individuals who have not experienced a coronary event. These findings represent an exciting advance that emphasizes the value of preventive efforts in curbing CHD.


Asunto(s)
Enfermedad Coronaria/prevención & control , Colesterol/sangre , Enfermedad Coronaria/sangre , Enfermedad Coronaria/tratamiento farmacológico , Enfermedad Coronaria/etiología , Dieta Aterogénica , Ejercicio Físico , Humanos , Medición de Riesgo , Cese del Hábito de Fumar , Triglicéridos/sangre
14.
J Appl Psychol ; 86(5): 897-913, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11596806

RESUMEN

There has been a growing interest in understanding what constructs are assessed in the employment interview and the properties of those assessments. To address these issues, the authors developed a comprehensive taxonomy of 7 types of constructs that the interview could assess. Analysis of 338 ratings from 47 actual interview studies indicated that basic personality and applied social skills were the most frequently rated constructs in this taxonomy, followed by mental capability and job knowledge and skills. Further analysis suggested that high- and low-structure interviews tend to focus on different constructs. Taking both frequency and validity results into consideration, the findings suggest that at least part of the reason why structured interviews tend to have higher validity is because they focus more on constructs that have a stronger relationship with job performance. Limitations and directions for future research are discussed.


Asunto(s)
Entrevistas como Asunto , Selección de Personal , Psicología Industrial , Humanos , Personalidad , Competencia Profesional , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Conducta Social
15.
Postgrad Med ; 83(8): 229-37, 241-2, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3375153

RESUMEN

High blood cholesterol levels are a major risk factor for coronary artery disease. Recent studies have shown that a cholesterol-lowering diet has a principal role in reducing coronary events in humans. A diet low in saturated fat and cholesterol is recommended for patients with a cholesterol level of more than 240 mg/dl or a level of between 200 and 239 mg/dl plus other risk factors. Measurement of low-density lipoprotein and high-density lipoprotein cholesterol levels provides a baseline value by which to gauge progress. Periodic assessment by the physician will give an indication of patient compliance. For patients who do not achieve desired goals within six months, drug therapy may be necessary.


Asunto(s)
Colesterol en la Dieta/administración & dosificación , Hipercolesterolemia/dietoterapia , Colesterol/sangre , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/prevención & control , Humanos , Hipercolesterolemia/sangre , Cooperación del Paciente
16.
J Gen Psychol ; 120(4): 489-97, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8189213

RESUMEN

We investigated the influence of windows on performance, mood, and satisfaction for different task types. Forty students worked computational or managerial tasks in offices with or without windows. Contrary to expectation, windowed offices did not effect higher performance, positive mood, or satisfaction. Actually, students felt slightly more confident (p < .10) and more in control (p < .01) in the windowless condition, suggesting a need for privacy to reduce evaluation apprehension. How windows affect performance, mood, and satisfaction remains unclear.


Asunto(s)
Afecto , Atención , Eficiencia , Satisfacción en el Trabajo , Iluminación , Medio Social , Adulto , Femenino , Humanos , Individualidad , Liderazgo , Masculino , Solución de Problemas
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