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1.
Opt Express ; 31(3): 3504-3519, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36785342

RESUMEN

Nowadays, atom-based quantum sensors are leaving the laboratory towards field applications requiring compact and robust laser systems. Here we describe the realization of a compact laser system for atomic gravimetry. Starting with a single diode laser operating at 780 nm and adding only one fiber electro-optical modulator, one acousto-optical modulator and one laser amplifier we produce laser beams at all the frequencies required for a Rb-87 atomic gravimeter. Furthermore, we demonstrate that an atomic fountain configuration can also be implemented with our laser system. The modulated system reported here represents a substantial advance in the simplification of the laser source for transportable atom-based quantum sensors that can be adapted to other sensors such as atomic clocks, accelerometers, gyroscopes or magnetometers with minor modifications.

2.
Opt Express ; 30(14): 24261-24275, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-36236984

RESUMEN

We introduce a new approach to determine if a cloud of cold atoms has or not a unique, well-defined temperature. In the first case, the temperature can be determined using the width of the velocity distribution. However, the temperature in a cloud of cold atoms may not be well-defined if the velocity distribution does not turn out to be Gaussian. In this case, the width of the velocity distribution cannot be associated to a unique temperature, and additional considerations exposed here should be followed to measure the temperatures of two groups of atoms forming the whole cloud. Also an uncertainty evaluation is presented.

3.
Semergen ; 49(3): 101921, 2023 Apr.
Artículo en Español | MEDLINE | ID: mdl-36645935

RESUMEN

OBJECTIVE: To describe the main retinal alterations detected by non-mydriatic retinal camera screening and to evaluate factors related to referral to ophthalmology in a population at high cardiovascular risk in Palmira, Colombia. MATERIALS AND METHODS: Cross-sectional observational study, which included 11,983 photographic imaging records of patients with hypertension and diabetes mellitus from Gesencro's S.A.S. comprehensive chronic disease care program between 2018 and 2020. Risk factors associated to referral to ophthalmology were evaluated with logistic regression, and crude and adjusted ORs (odds ratios) were obtained. RESULTS: A total of 11,880 records were analyzed; 67.7±12years old, and 69.5% were women. Among the retinal alterations were patients with diabetic retinopathy classified as more than mild in 10% and gradeI hypertensive retinopathy in 54.9% right eye, 51.9% left eye. Macular edema was also identified. Only 2069 patients (17.4%) required referral to ophthalmology, and for imaging control 82.6%. In the multivariate analysis, the risk factors associated with the probability of being referred were male gender, age 60years and older, glycosylated hemoglobin out-of-target, advanced chronic kidney disease and the microalbumin-to-creatinine ratio moderate to severely elevated. CONCLUSION: This study makes it possible to determine the importance of screening with a non-mydriatic retinal camera in patients at high cardiovascular risk to detect retinal abnormalities and assess risk factors associated with referral to ophthalmology. Early documentation of ocular compromise in these patients could prevent and avoid visual impairment and blindness.


Asunto(s)
Enfermedades Cardiovasculares , Retinopatía Diabética , Oftalmología , Humanos , Masculino , Femenino , Persona de Mediana Edad , Oftalmología/métodos , Estudios Transversales , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Factores de Riesgo , Tamizaje Masivo/métodos , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/epidemiología , Factores de Riesgo de Enfermedad Cardiaca , Derivación y Consulta
4.
Rev Gastroenterol Mex (Engl Ed) ; 86(1): 13-20, 2021.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32173132

RESUMEN

INTRODUCTION AND AIMS: Neoadjuvant therapy in rectal cancer is associated with a decrease in tumor size and is the therapeutic indication for patients with T3 or T4 tumors or lymph node involvement. Our aim was to describe the frequency of pathologic response and the survival rate in patients that underwent neoadjuvant therapy for rectal cancer. MATERIALS AND METHODS: A retrospective follow-up study with a survival analysis was conducted. Patients with locally advanced rectal cancer that received neoadjuvant treatment and were operated on at the Instituto de Cancerología Las Américas (Medellín, Colombia) were analyzed. Survival was calculated using the Kaplan-Meier method. RESULTS: A total of 152 patients were included. Mean patient age was 59 years (12.8 SD), 53.9% were men, and 58.6% of the patients were diagnosed with stage IIIB disease. The pathologic complete response (pCR) was achieved in 17% of the patients. A total of 146 (96.1%) patients received the chemoradiotherapy protocol. Fifty-two (34.2%) patients developed metastasis and/or relapse, and one (3.8%) of those patients had presented with pCR. The median follow-up period was 33 months (Q1-Q3: 20-45), with an overall survival rate of 79.5% (95% CI 70.9-85.8). The 5-year survival rate for the patients that had pCR was 80% (95% CI 20.3-96.9). CONCLUSIONS: The frequency of pCR was similar to that in other published studies and disease recurrence was lower, compared with patients with no response. The 5-year survival rate in patients with pCR was high, albeit lower than that reported in other studies.

6.
Rev. int. med. cienc. act. fis. deporte ; 23(92): 365-382, aug.-sept. 2023. ilus, tab, graf
Artículo en Inglés | IBECS (España) | ID: ibc-229410

RESUMEN

Objective: To determine the effect of an exercise program on functional status, pain perception and self-perceived health (SPH) in patients with and without chronic kidney disease (CKD) in primary care (PC). Methodology: Group pre- and postintervention, single-center study of adults with and without CKD in PC. The intervention was a 6-week multicomponent exercise program. Results were evaluated with scales of functional assessment, pain perception and SPH. Results:A total of 523 adults participated (256 with CKD and 267 without CKD). Significant increases were found for the Barthel index, the Short Physical Performance Battery SPPB) score, grip strength and calf perimeter. There was improvement in pain perception and SPH (p < 0.001) in all patients. Conclusions: In the studied sample, an exercise program produced improvements in functional status, pain perception and SPH (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Insuficiencia Renal Crónica/rehabilitación , Terapia por Ejercicio , Estudios de Casos y Controles , Resultado del Tratamiento
7.
Int J Impot Res ; 17 Suppl 1: S52-6, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16391544

RESUMEN

Sexuality is an important component of emotional and physical intimacy that men and women experience through their lives. Male erectile dysfunction (ED) and female sexual dysfunction increase with age. About a third of the elderly population has at least one complaint with their sexual function. However, about 60% of the elderly population expresses their interest for maintaining sexual activity. Although aging and functional decline may affect sexual function, when sexual dysfunction is diagnosed, physicians should rule out disease or side effects of medications. Common disorders related to sexual dysfunction include cardiovascular disease, diabetes, lower urinary tract symptoms and depression. Early control of cardiovascular risk factors may improve endothelial function and reduce the occurrence of ED. Treating those disorders or modifying lifestyle-related risk factors (eg obesity) may help prevent sexual dysfunction in the elderly. Sexuality is important for older adults, but interest in discussing aspects of sexual life is variable. Physicians should give their patient's opportunity to voice their concerns with sexual function and offer them alternatives for evaluation and treatment.


Asunto(s)
Envejecimiento/fisiología , Disfunciones Sexuales Fisiológicas/etiología , Disfunciones Sexuales Psicológicas/etiología , Anciano , Anciano de 80 o más Años , Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/terapia , Diabetes Mellitus/fisiopatología , Disfunción Eréctil/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Neoplasias de la Próstata/complicaciones , Neoplasias de la Próstata/terapia , Disfunciones Sexuales Fisiológicas/epidemiología , Disfunciones Sexuales Psicológicas/epidemiología , Sexualidad
9.
Health Phys ; 58(3): 275-81, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2312293

RESUMEN

Continuous air monitor (CAM) samplers are used to detect radioactive aerosol particles in nuclear facilities and to provide alarm signals should the concentrations exceed a multiple of the derived air concentration (DAC) of the radionuclide of concern in a set amount of time. Aerosol particles are drawn into a CAM sampler where collection is to take place upon a filter. Radioactivity of the particles is determined with a detector that is placed in close proximity to the filter face. An important determinant of CAM performance is the ability of the inlet and body of the CAM to transport particulate matter in the inhalable-size range (less than or equal to 10 microns aerodynamic diameter) to the filter without substantial loss or bias with respect to particulate size. Three types of CAM samplers were tested in a low-velocity aerosol wind tunnel to determine the degree to which particles penetrate through the flow systems to the collection filter under conditions typical of normal room air exchange rates. Two air velocities were used: 0.3 and 1.0 m s-1. The CAM samplers were primarily operated at a flow rate of 56.6 L min-1, although some tests were conducted at a flow rate of 28.3 L min-1. The CAM units were prototypes manufactured by Kurz Instruments, Eberline Instrument Corporation, and Victoreen Inc. These three units represent three different approaches to CAM head design. At an air speed of 1 m s-1, aerosol penetration to the filters of the Kurz unit was essentially 100% for particle sizes of 3 and 7-microns aerodynamic diameter and was 86% for a size of 15 microns. For the Eberline sampler, the penetration was over 80% for 3-microns particles but was reduced to less than 2% for 7-microns particles. The victoreen sampler showed penetration values of 98% for 3-microns aerodynamic diameter particles, 88% for 7-microns particles and 4% for a size of 15 microns. Air speed had little effect on the penetration results for the two speeds which were tested. Tests were conducted to determine the uniformity of deposits on the filters of the CAM samplers. For a particle size of 10 microns, the deposits were nonuniform for all three of the instruments.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Contaminantes Radiactivos del Aire/análisis , Contaminantes Atmosféricos/análisis , Monitoreo de Radiación/instrumentación , Aerosoles , Estudios de Evaluación como Asunto
10.
Health Phys ; 61(1): 97-103, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2061053

RESUMEN

A new continuous air monitor (CAM) sampler for assessing alpha-emitting transuranic aerosol particles has been developed. The system has been designed to permit collection of particles that can potentially penetrate into the thoracic region of the human respiratory system. Wind tunnel testing of the sampler has been used to characterize the penetration of aerosol to the collection filter. Results show that greater than or equal to 50% of 10-micrograms aerodynamic equivalent diameter (AED) particles are collected by the filter at wind speeds of 0.3 to 2 m s-1 and at sampling flow rates of 28 to 113 L min-1 (1 to 4 cfm). The deposition of 10-microns AED particles takes place primarily in the center of the filter, where the counting efficiency of the detector is highest.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Partículas alfa , Monitoreo del Ambiente/instrumentación , Monitoreo de Radiación/instrumentación , Aerosoles , Estudios de Evaluación como Asunto
11.
Health Phys ; 62(5): 400-6, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1559808

RESUMEN

A continuous air monitor has been developed that includes provisions for improving the detection of alpha-emitting aerosol particles in the presence of radon/thoron progeny that are unattached to ambient aerosol particles. Wind tunnel tests show that 80% of 10-microns aerodynamic equivalent diameter particles penetrate the flow system from the ambient air to the collection filter when the flow rate is 57 L min-1 (2 cfm) and the wind speed is 1 m s-1. Uniformity of aerosol collection on the filter, as characterized by the coefficient of variation of the areal density deposits, is less than 15% for 10-microns aerodynamic-equivalent-diameter aerosol particles. Tests with unattached radon daughters in a flow-through chamber showed that approximately 99% of the 218Po was removed by an inlet screen that is designed to collect radon daughters that are in the size range of molecular clusters. The inlet screen offers the opportunity to improve the signal-to-noise ratio of energy spectra in the regions of interest (subranges of the energy spectrum) of transuranic elements and thereby enhance the performance of background compensation algorithms.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Partículas alfa , Monitoreo de Radiación/instrumentación , Aerosoles
12.
Health Phys ; 76(1): 17-26, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9883943

RESUMEN

The U.S. EPA has approved Alternate Reference Methodologies for sampling radionuclide aerosol particles from stacks and ducts of U.S. DOE facilities. The approach allows use of single point sampling with shrouded probes from locations where both fluid momentum and contaminant concentration are well mixed across the flow cross section. For existing stacks and ducts that do not have locations where there is adequate mixing, we have developed a generic mixing system that will generate conditions suitable for single point sampling. The coefficients of variation of the velocity, tracer gas, and 10 microm aerodynamic diameter aerosol particles profiles are all less than 10%, which are well within the EPA limit of 20%. Mixing is affected neither by size of the system nor by flow rate, provided the flow is turbulent.


Asunto(s)
Contaminación Radiactiva del Aire/análisis , Monitoreo de Radiación/normas , Contaminación Radiactiva del Aire/estadística & datos numéricos , Agencias Gubernamentales , Monitoreo de Radiación/instrumentación , Monitoreo de Radiación/métodos , Estándares de Referencia , Reproducibilidad de los Resultados , Sesgo de Selección , Estados Unidos , United States Environmental Protection Agency
13.
Health Phys ; 70(1): 25-35, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7499148

RESUMEN

Alternative reference methodologies have been developed for sampling of radionuclides from stacks and ducts, which differ from the methods previously required by the United States Environmental Protection Agency. These alternative reference methodologies have recently been approved by the U.S. EPA for use in lieu of the current standard techniques. The standard EPA methods are prescriptive in selection of sampling locations and in design of sampling probes whereas the alternative reference methodologies are performance driven. Tests were conducted in a stack at Los Alamos National Laboratory to demonstrate the efficacy of some aspects of the alternative reference methodologies. Coefficients of variation of velocity, tracer gas, and aerosol particle profiles were determined at three sampling locations. Results showed that numerical criteria placed upon the coefficients of variation by the alternative reference methodologies were met at sampling stations located 9 and 14 stack diameters from the flow entrance, but not at a location that was 1.5 diameters downstream from the inlet. Experiments were conducted to characterize the transmission of 10 microns aerodynamic diameter liquid aerosol particles through three types of sampling probes. The transmission ratio (ratio of aerosol concentration at the probe exit plane to the concentration in the free stream) was 107% for a 113 L min-1 (4-cfm) anisokinetic shrouded probe, but only 20% for an isokinetic probe that follows the existing EPA standard requirements. A specially designed isokinetic probe showed a transmission ratio of 63%. The shrouded probe performance would conform to the alternative reference methodologies criteria; however, the isokinetic probes would not.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Aerosoles , Centrales Eléctricas
14.
Compr Ther ; 25(3): 169-73, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10200907

RESUMEN

Mind and heart are connected by neurocardiologic pathways. Psychosocial risk factors produce sympathetic activation, resulting in mortality in coronary artery disease. Aspirin, exercise, and psychosocial and spiritual supports are important resources in protecting the heart against these risk factors.


Asunto(s)
Enfermedad Coronaria/fisiopatología , Enfermedad Coronaria/psicología , Enfermedad Coronaria/prevención & control , Humanos , Factores de Riesgo , Estrés Psicológico/complicaciones , Estrés Psicológico/prevención & control
15.
Compr Ther ; 27(2): 117-21, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11430258

RESUMEN

Diogenes syndrome (DS) is characterized by severe self-neglect, domestic squalor, social withdrawal, syllogomania, and refusal of help that may be precipitated by stressful events. Secondary DS is related to mental disorders. Its management includes day care center and community care.


Asunto(s)
Trastornos Mentales , Aislamiento Social , Factores de Edad , Anciano , Humanos , Higiene , Trastornos Mentales/diagnóstico , Trastornos Mentales/epidemiología , Trastornos Mentales/etiología , Trastornos Mentales/terapia , Síndrome
16.
SEMERGEN, Soc. Esp. Med. Rural Gen. (Ed. Impr.) ; 49(3): [e101873], abr. 2023. ilus, tab, graf
Artículo en Español | IBECS (España) | ID: ibc-219400

RESUMEN

Objetivo Describir las principales alteraciones retinianas detectadas por screening con cámara retinal no midriática y evaluar los factores relacionados con la derivación a oftalmología en una población de alto riesgo cardiovascular en Palmira, Colombia. Materiales y métodos Estudio observacional de tipo transversal, con 11.983 registros fotográficos de pacientes con hipertensión y diabetes mellitus del programa de enfermedades crónicas de Gesencro S.A.S. entre 2018 y 2020. Se evaluaron con regresión logística los factores de riesgo relacionados con la derivación a oftalmología y se obtuvieron los odds ratios (OR) crudos y ajustados. Resultados Se analizaron 11.880 registros; la edad media fue de 67,7±12años, y el 69,5% fueron mujeres. Entre las alteraciones retinianas se encontraron pacientes con retinopatía diabética clasificada como más que leve (10%) y gradoI de retinopatía hipertensiva (54,9% ojo derecho, 51,9% ojo izquierdo). También se identificó edema macular (15%). Solo 2.069 (17,4%) pacientes requirieron derivación a oftalmología; el 81,3% requirieron control a 1año y el 1,3% a los 6meses. En el análisis multivariado los factores de riesgo que se relacionaron con la probabilidad para ser derivados fueron: el género masculino, la edad mayor o igual a 60años, la hemoglobina glucosilada (HbA1c) fuera de metas, la enfermedad renal crónica avanzada y la razón microalbúmina-creatinina moderada a severamente elevada. Conclusión Este estudio permitió determinar la importancia que tiene el screening con cámara retinal no midriática en pacientes de alto riesgo cardiovascular para detectar alteraciones retinianas y evaluar factores de riesgo asociados con derivación a oftalmología. El documentar tempranamente el compromiso ocular en estos pacientes podría prevenir y evitar la discapacidad visual y la ceguera (AU)


Objective To describe the main retinal alterations detected by non-mydriatic retinal camera screening and to evaluate factors related to referral to ophthalmology in a population at high cardiovascular risk in Palmira, Colombia. Materials and methods Cross-sectional observational study, which included 11,983 photographic imaging records of patients with hypertension and diabetes mellitus from Gesencro's S.A.S. comprehensive chronic disease care program between 2018 and 2020. Risk factors associated to referral to ophthalmology were evaluated with logistic regression, and crude and adjusted ORs (odds ratios) were obtained. Results A total of 11,880 records were analyzed; 67.7±12years old, and 69.5% were women. Among the retinal alterations were patients with diabetic retinopathy classified as more than mild in 10% and gradeI hypertensive retinopathy in 54.9% right eye, 51.9% left eye. Macular edema was also identified. Only 2069 patients (17.4%) required referral to ophthalmology, and for imaging control 82.6%. In the multivariate analysis, the risk factors associated with the probability of being referred were male gender, age 60years and older, glycosylated hemoglobin out-of-target, advanced chronic kidney disease and the microalbumin-to-creatinine ratio moderate to severely elevated. Conclusion This study makes it possible to determine the importance of screening with a non-mydriatic retinal camera in patients at high cardiovascular risk to detect retinal abnormalities and assess risk factors associated with referral to ophthalmology. Early documentation of ocular compromise in these patients could prevent and avoid visual impairment and blindness (AU)


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Enfermedades Cardiovasculares/diagnóstico , Retinopatía Diabética/diagnóstico , Retinopatía Hipertensiva/diagnóstico , Estudios Transversales , Factores de Riesgo , Tamizaje Masivo , Derivación y Consulta
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