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We report a fully quantum-dynamical study of the intramolecular vibrational energy redistribution (IVR) in the electronic ground state of carbonyl sulfide, which is a prototype of an isolated many-body quantum system with strong internal couplings and non-Rice-Ramsperger-Kassel-Marcus (RRKM) behavior. We pay particular attention to the role of many-body localization and the approach to thermalization, which currently are topics of considerable interest, as they pertain to the very foundations of statistical mechanics and thermodynamics. We employ local-mode (valence) coordinates and consider initial excitations localized in one local mode, with energies ranging from low to near the dissociation threshold, where the classical dynamics have been shown to be chaotic. We propagate the nuclear wavepacket on the potential energy surface by means of the numerically exact multiconfiguration time-dependent Hartree method and employ mean local energies, time-dependent and time-averaged populations in quantum number space, energy distributions, entanglement entropies, local population distributions, microcanonical averages, and dissociation probabilities, as diagnostic tools. This allows us to identify a continuous localization â delocalization transition in the energy flow, associated with the onset of quantum chaos, as the excitation energy increases up to near the dissociation threshold. Moreover, we find that at this energy and â¼1 ps the molecule nearly thermalizes. Furthermore, we observe that IVR is so slow that the molecule begins to dissociate well before such quasi-thermalization is complete, in accordance with earlier classical-mechanical predictions of non-RRKM behavior.
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Resumen: En este trabajo se presenta un sistema electrónico, basado en la medición de la distribución del peso en los pies, cuyo objetivo es coadyuvar en la evaluación postural. La evaluación postural utilizada por los fisioterapeutas para corregir problemas musculo-esqueléticos derivados por la edad, accidentes, enfermedades, etc. El sistema electrónico construido se validó preliminarmente utilizando videocámaras para corroborar la postura en un sujeto. Con los datos obtenidos se pudo confirmar que el sistema propuesto es capaz de ayudar en la corrección de la postura en tiempo real. La limitación principal de este trabajo es el reducido número de pruebas, por lo que sólo se presentan resultados preliminares. La originalidad de este trabajo reside principalmente en la solución propuesta para evaluar y corregir la postura por medio de un sistema electrónico, novedoso por el método empleado y su portabilidad. Derivado de los resultados presentados se puede concluir que sistema propuesto es capaz de ayudar a corregir la postura en tiempo real.
Abstract: This paper presents an electronic system aimed to assist on the postural evaluation by measuring the weight distribution on the feet. Postural evaluation is commonly used by physiotherapists in order to correct muscle-skeletal problems such as those derived from ageing, accidents, diseases, etc. The developed electronic system was validated preliminary using video cameras to confirm the correct postures of the subject under test. With the obtained data it is possible to corroborate that the proposed system is capable to assist on the correction of the postural position in real time. The main limitation of this work is the reduced number of tests, due to this only preliminary results are presented. The main novelty of this work is the proposed solution to evaluate and help to correct the posture by using a portable electronic device based on force sensors. Derived from the presented results it can be concluded that the proposed system is capable to assist on the evaluation and correction of postural position in real time.
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UNLABELLED: The incidence rate of periprosthetic fractures has increased in the past decade. Osteolysis, age and preoperative function are factors that influence morbidity. Treatment options include conservative and surgical treatment. OBJECTIVES: To conduct a study analyzing the functional results of the surgical treatment of periprosthetic hip fractures at the ABC Medical Center considering preoperative and postoperative variables. MATERIAL AND METHODS: Cross-sectional retrospective study of patients with a diagnosis of periprosthetic hip fracture between January 2000 and December 2011, classified using the Vancouver system. The Oxford Hip Score was used pre- and postoperatively as a functional measure. The variables to evaluate included age, sex, surgical technique, and the time elapsed between primary surgery and the periprosthetic fracture. RESULTS: Twenty-five patients were analyzed; frequency was 3.3 cases per year. 80% of periprosthetic fractures were postoperative; 72% were total hip arthroplasties. The time elapsed between primary surgery and the traumatic event was 2 to 4 years (68%), with a mean of 4.5 years for hemiarthroplasties and 3.9 years for total arthroplasties. Patients who according to the Oxford Hip Score had good function maintained their results; 75% of those with moderate function maintained their score. Patients with poor function improved. CONCLUSIONS: At the ABC Medical Center, the outcomes of the treatment of periprosthetic hip fractures are considered as good according to the Oxford Hip Score.
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Artroplastia de Quadril/efeitos adversos , Fraturas do Quadril/cirurgia , Fraturas Periprotéticas/cirurgia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
AIM: The objective of this work is to present a new collaborative method for teaching administration of anesthetic block in dentistry, with three-dimensional anatomical models used to improve learning and thereby increase safety, reduce anxiety, and improve the performance of students during the administration of anesthesia in the patients. MATERIALS AND METHODS: Three-dimensional (3D) models of skulls were made that reproduced all innervations of the V th cranial nerve (trigeminal nerve), as well as some blood vessels, glands, and muscles of mastication. For teaching the local anesthetic techniques we prepared pictures and videos of the administration of anesthesia in the models , which were presented to 130 students in two universities in Brazil. With the help of the models the students could follow the path of the nerves to be anesthetized and identify the anatomical points of reference for the correct positioning of the needle in the tissues. After the presentation the students answered a questionnaire aiming to assess the effect of the 3D models on learning. RESULTS: Eighty-eight percent of students rated the material as excellent, 12% as good, 0% as regular, and 0% as bad (unnecessary materials). After the presentation, 70% of the students felt confident about being able to achieve the nerve block in patients. CONCLUSION: When exposed to an appropriate method, students recognized the importance of knowledge of anatomy for learning local anesthetic techniques. This method improved the quality of education and increased patient safety during the first injection.
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Anestesia Dentária/métodos , Educação em Odontologia/métodos , Modelos Anatômicos , Crânio/anatomia & histologia , Cirurgia Bucal/educação , Brasil , Avaliação Educacional , Humanos , Gravação em VídeoRESUMO
INTRODUCTION: Tumors of the digestive system are considered to be a public health problem because of their elevated mortality rate. In Mexico, gastric cancer and colon cancer rank fourth and fifth, respectively, following tracheal, bronchial, and lung cancer, and there has been an increase in their frequency in the last few years. However, there are no specific studies that have evaluated their epidemiologic behavior in Veracruz. OBJECTIVE: To determine the frequency of digestive system cancer in five health institutions in the city of Veracruz and to describe its epidemiologic behavior over a five-year period. MATERIAL AND METHODS: Annual statistics from the following hospitals were reviewed: the Instituto Mexicano del Seguro Social, the Secretaría de Salud, the Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, Petróleos Mexicanos, and the Secretaría de la Defensa Nacional within the time frame of January 2005 to December 2009. Diagnoses based on histopathology were recorded, along with patient age and sex. RESULTS: A total of 1803 cases of digestive tract cancers were detected: 52% were men and 48% were women. A yearly increase in the number of cases was observed with colon cancer being in first place, followed by stomach cancer and rectal cancer. CONCLUSIONS: The increase in digestive system cancer cases over the last five years in Veracruz underlines the need to evaluate the implementation of screening programs for the at-risk population and to study the different etiologic factors involved in its manifestation.
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Neoplasias do Sistema Digestório/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Saúde da População Urbana , Adulto JovemRESUMO
A conceptually appealing and computationally economical course-grained molecular-orbital (MO) theory for extended quasilinear molecular heterostructures is presented. The formalism, which is based on a straightforward adaptation, by including explicitly the vacuum, of the envelope-function approximation widely employed in solid-state physics leads to a mapping of the three-dimensional single-particle eigenvalue equations into simple one-dimensional hole and electron Schrödinger-like equations with piecewise-constant effective potentials and masses. The eigenfunctions of these equations are envelope MO's in which the short-wavelength oscillations present in the full MO's, associated with the atomistic details of the molecular potential, are smoothed out automatically. The approach is illustrated by calculating the envelope MO's of high-lying occupied and low-lying virtual π states in prototypical nanometric heterostructures constituted by oligomers of polyacetylene and polydiacetylene. Comparison with atomistic electronic-structure calculations reveals that the envelope-MO energies agree very well with the energies of the π MO's and that the envelope MO's describe precisely the long-wavelength variations of the π MO's. This envelope MO theory, which is generalizable to extended systems of any dimensionality, is seen to provide a useful tool for the qualitative interpretation and quantitative prediction of the single-particle quantum states in mesoscopic molecular structures and the design of nanometric molecular devices with tailored energy levels and wavefunctions.
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Elétrons , Nanoestruturas/química , Compostos Orgânicos , Teoria Quântica , Simulação por Computador , Estrutura Molecular , Compostos Orgânicos/químicaRESUMO
INTRODUCTION: To determinate the etiology and risk factors for a first episode of cerebral ischemia in young adults at three hospitals of Lima and Callao-Peru. METHODS: Multicentric study carried out at three national hospitals in Lima. The sample included 30 patients with a first episode of stroke and 60 controls matched by age and sex 2:1 with the patients. Serum biochemistry studies, EKGs and echocardiograms were done. Etiologies were classified based on the classification of Baltimore-Washington Cooperative Young Stroke Study. RESULTS: The most frequent etiologies were cardiac embolism and atherosclerotic valvular heart disease, which were 30% of the cases (9 patients) each one. Hypertriglyceridemia (p=0.014), valvular heart disease (p=0.001) and hormonal contraception/replacement therapy (p=0.002) were independent risk factors for a first episode of cerebral ischemia in peruvian young adults. Motor deficiency was the most frequent presentation (50.0%). Intracraneal hypertension and urinary tract infection were the most frequent complications during acute ischemia and mortality was raised up to 10%. CONCLUSIONS: The hypertriglyceridemia, valvular heart disease and the use of oral contraceptives are independent risk factors for a first episode of ischemia in young adults from three hospitals of Lima and Callao. The most frequent etiologies were cardiac embolism and atheroesclerotic valvular heart disease.
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Isquemia Encefálica/etiologia , Adulto , Aterosclerose/complicações , Isquemia Encefálica/fisiopatologia , Embolia/complicações , Feminino , Doenças das Valvas Cardíacas/complicações , Humanos , Masculino , Peru , Fatores de RiscoRESUMO
We compared the use of personal digital assistants (PDAs) against the use of standard paper questionnaires for collecting survey data. The evaluation consisted of qualitative approaches to document the process of introducing PDAs. Fieldwork was carried out during June-July 2005 at 12 sites in Bolivia. Data collectors reacted positively to the use of the PDAs and noted the advantages and disadvantages of paper and PDA data collection. A number of difficulties encountered in the use of PDA technology serve as a warning for investigators planning its adoption. Problems included incompatible data files (which impeded the ability to interpret data), an inadequate back-up protocol, and lack of a good 'fit' between the technology and the study. Ensuring the existence of a back-end database, developing an appropriate and adequate back-up protocol, and assessing whether a technology 'fits' the project are important factors in weighing the decision to collect data using PDAs.
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Computadores de Mão , Pesquisas sobre Atenção à Saúde/instrumentação , Atitude Frente aos Computadores , Bolívia , Humanos , Gestão da Informação/métodos , Entrevistas como Assunto , Projetos Piloto , Inquéritos e QuestionáriosRESUMO
Objetivo: La mayoría de las hidronefrosis antenatales se resuelven en forma espontánea, pero aquellas que presentan dilataciones mayores o severas requieren, por lo general, tratamiento quirúrgico. Existe un subgrupo de éstas que, pese a su gran dilatación, presentan función renal normal. El objetivo del presente estudio es evaluar a largo plazo aquellas dilataciones consideradas severas que han sido tratadas en forma conservadora. Método: Revisión de fichas clínicas e imagenología de pacientes pediátricos con diagnóstico de hidronefrosis atendidos en nuestra unidad. Resultado: Entre 1998 y 2005 se han atendido en nuestra unidad 289 niños con diagnóstico prenatal de malformación de la vía urinaria; 159 son hidronefrosis. Hubo 106 niños (67 por ciento) y 53 niñas (33 por ciento). De éstos, 37 pacientes eran severos; 15 se operaron y 22 se manejaron en forma conservadora con ecografía y renograma seriado. Nueve de los 22 (41 por ciento) requirieron pieloplastia a los 17 meses en promedio. En las 13 unidades restantes aún en seguimiento promedio de 27 meses (rango 4-60 meses), la función renal está conservada. No se encontraron diferencias significativas con respecto a función renal, grosor de parénquima y diámetro de la pelvis entre aquellos manejados quirúrgicamente v/s aquellos seguidos conservadoramente. Conclusiones: Proponemos que no toda hidronefrosis severa debe ser tratada quirúrgicamente. Creemos que los que son asintomáticos y tienen función renal normal deben seguirse en forma seriada con ecografía y cintigrafía renal para decidir su conducta. Aún es necesario encontrar algún método que permita prevenir el daño renal, donde el elaborar un protocolo prospectivo que evalúe las características del parénquima renal y su progresión en el tiempo puede tener alguna cabida.
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Humanos , Masculino , Feminino , Lactente , Dilatação Patológica/diagnóstico , Hidronefrose/diagnóstico , Hidronefrose/terapia , Obstrução Uretral/embriologia , Sistema Urinário/anormalidades , Diagnóstico Pré-Natal , SeguimentosRESUMO
The presence of several Mycobacterium species was determined in 68 New World monkeys kept captive in the Cali Zoo. One hundred and thirty-three gastric lavage and blood samples were evaluated for mycobacterial presence by Ziehl-Neelsen (ZN) staining, culture and PCR amplification of the Mycobacterium tuberculosis Mtp40 species-specific gene. Mycobacteria other than tuberculosis (MOTT) were identified by PCR restriction fragment length polymorphism (RFLP). Different species of mycobacteria were detected in 65% of the primate population studied by Alpha Antigen PCR. Eleven percent were positive for Mtp40 PCR amplification, being diagnosed as having M. tuberculosis, and acid-fast bacilli were observed in 23% by ZN staining. MOTT were isolated from samples taken from 37 primates by culturing; according to the RFLP analysis, three strains were classified as belonging to the MAISS complex (Mycobacterium avium-intracellulare-scrofulaceum-simiae) and eight more, isolated from soil inside the cages, were categorized as environmental contaminants. Mycobacterium spp. were detected in 13 different New World primate species showing that PCR amplification of the Mtp40 gene is a better tool than culture for M. tuberculosis detection in captive animals and that RFLP is a useful technique for MOTT identification.
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Cebidae , Doenças dos Macacos/microbiologia , Infecções por Mycobacterium/veterinária , Mycobacterium/isolamento & purificação , Animais , Animais de Zoológico , Antígenos de Bactérias/química , Antígenos de Bactérias/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Doenças dos Macacos/epidemiologia , Mycobacterium/classificação , Mycobacterium/genética , Infecções por Mycobacterium/sangue , Infecções por Mycobacterium/epidemiologia , Infecções por Mycobacterium/microbiologia , Hibridização de Ácido Nucleico , Filogenia , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Fosfolipases Tipo C/química , Fosfolipases Tipo C/genéticaRESUMO
The dispenser Microdrop is a laboratory work station for bioanalytical laboratories. The workstation combines into a single programmable system the capability of performing automatic transfer of liquid samples between of a plurality of receptacles...
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Equipamentos de LaboratórioRESUMO
La microlitiasis testicular (MT) es una entidad poco común, caracterizada por el depósito de calcio en el lumen de los túbulos seminíferos. Su verdadera incidencia y etiopatogenia no han sido definidos. La MT tiene una apariencia ultrasonográfica característica, que consiste en la presencia de focos hiperecogénicos menores de 2 mm, distribuidos en forma difusa en el parénquima testicular, generalmente en forma bilateral.
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Humanos , Masculino , Criança , Doenças Testiculares/diagnóstico , Doenças Testiculares/patologia , Doenças Testiculares , Túbulos SeminíferosRESUMO
BACKGROUND: Simple intratesticular cysts are rare in children and have been considered the most uncommon cause of scrotal cystic masses in this age group. The exact etiology of these lesions is still unclear. High-resolution ultrasonography has been proved to be a reliable and accurate imaging modality in the evaluation of scrotal abnormalities in children. PATIENTS AND METHODS: We report the sonographic findings in five boys aged from 4 to 10 months who presented with a scrotal mass and had a simple intratesticular cyst. Ultrasonography showed that all of them displayed a characteristic appearance and provided the necessary information to perform conservative surgery, with testicular preservation in four infants. In one infant, the cyst involved most of the testis, and an orchiectomy was performed. RESULTS: Pathological examination revealed a single smooth-walled cystic structure, with clear and serous fluid, lined with flattened epithelial cells in all of the infants. CONCLUSION: Our findings appear to support the hypothesis that these cysts could correspond to mesothelial inclusions. Sonographically, differential diagnosis should include mainly epidermoid cysts of the testis, which are mostly cystic but characteristically contain some echoes within them, in contrast to simple cysts and cysts of the tunica albuginea, which lie outside the testicular parenchyma.
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Cistos/diagnóstico por imagem , Cistos/patologia , Doenças Testiculares/diagnóstico por imagem , Doenças Testiculares/patologia , Testículo/patologia , Cistos/cirurgia , Humanos , Lactente , Masculino , Microscopia Eletrônica , Doenças Testiculares/cirurgia , UltrassonografiaRESUMO
OBJECTIVE: To determine bone density in the third lumbar vertebra in a group of men and women from the Mexico City correlating the morphometric characteristics of vertebral body by specific techniques and to detect groups with alterations like osteoporosis or osteopenia. METHODOLOGY: The study was made in third lumbar vertebra from 23 patients dead of the Medical Service Forense-México, 8 women between 31 to 72 years old and 15 men between 25 yo 62 years old. The studies were: Radiological, bone densitometry and by image in which was determined density of vertical and horizontal trabeculaes. With x-ray technique in scanning electron microscopy was determined in form semiquantitative the presence of Ca, P, Mg and Na, and Ca distribution by technique of x-ray energy dispersed. RESULTS: In the radiological trail all vertebras of the female group were abnormal, the major finding was degenerative feature; 5 Showed trabeculation increased 3 fractured; in the males group 7 patients were normal, degenerative fracture in 8; of these six had densitometry with DEXA; in the females group only one was normal, 3 osteopenia, 5 osteoporosis; in the male group: 5 osteopenia and 5 osteoporosis. Scanning electron microscopy examination exhibit a homogeneous and dense expression pattern, wherever SEM demonstrated the absence or decrease of deposit calcium in osteoporosis. A morphometric examination of the trabecular thickness demonstrates a difference between the two sexes. The normal median was 222.1 microns, the osteoporosis range was 126.3 to 156.2 microns in the female osteoporosis, in male group was found two normal values with a trabecular density mean of 249.7 microns, in the last two cases one with osteopenia and the other with osteoporosis, the mean value was 186.4 microns. CONCLUSIONS: In the present study, was demonstrated that the degenerative alterations in osteoporosis and osteopenia in young people are more frequent to respect other reports. The following observations require special emphasis either because they provide clues to the mechanism of altered expression of calcium: Genetic, ethnic, consume, sedentary and others.
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Vértebras Lombares/diagnóstico por imagem , Osteoporose/diagnóstico , Adulto , Idoso , Densidade Óssea , Doenças Ósseas Metabólicas , Densitometria , Feminino , Humanos , Vértebras Lombares/patologia , Masculino , México/epidemiologia , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Osteoporose/patologia , Radiografia , Fatores SexuaisRESUMO
Salivary gland lesions are uncommon in children and may be related to the parotid, submandibular or sublingual glands. Inflammatory lesions are the most common cause of salivary gland abnormalities in children and can be due to acute viral, acute suppurative, or recurrent acute or chronic inflammation. Intraparotid lymphadenitis may also occur, as in cat-scratch disease or in other causes of cervical lymphadenitis. Salivary gland neoplasms are rare in children, and most of them are benign including mainly hemangioma, pleomorphic adenoma, or lymphangioma. Other lesions, such as sialolithiasis, mucocele, or ranula, may also be seen. Ultrasonography should be the initial imaging study used for the examination of salivary gland lesions in children, given the fact that most of such lesions are benign and are shown up clearly by sonography. In most cases, this technique permits the differentiation of intraglandular and extraglandular lesions, and may suggest the correct diagnosis. The entire lesion could not be totally depicted by US however, and other imaging techniques such as CT or MRI may be necessary. Vascular lesions can be demonstrated more clearly through the use of color Doppler imaging. Some of the lesions may appear similar, and clinical correlation is important for the differential diagnosis. This article discusses the sonographic appearance and clinical manifestations of the spectrum of salivary gland abnormalities that may occur in children.
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Doenças das Glândulas Salivares/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Doenças das Glândulas Salivares/epidemiologia , Neoplasias das Glândulas Salivares/diagnóstico por imagem , Neoplasias das Glândulas Salivares/epidemiologia , Sialadenite/diagnóstico por imagem , Sialadenite/epidemiologia , UltrassonografiaRESUMO
La ventilación mecánica plantea problemas técnicos en lo fijación de las mangueras del ventilador y del tubo endotraqueal. Para ese efecto se muestra un dispositivo de acrílico en forma de arco de angulación variable que satisface los necesidades de fijación de los mangueras y tubo endotroqueal, fácil manejo, aseo y adecuado acceso al recién nacido. El dispositivo es además de bajo costo y su uso ha sido probado satisfactoriamente con el personal médico y de apoyo de la unidad de recién nacidos
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Humanos , Recém-Nascido , Respiração Artificial/instrumentação , Ventiladores Mecânicos , Desenho de Equipamento , Incubadoras para Lactentes , Intubação Intratraqueal/instrumentação , Berçários HospitalaresRESUMO
Two cases of relapsing malaria infection by Plasmodium vivax from Guatemala are presented in patients treated with current standard doses of chloroquine and primaquine. The difficulties in recognizing resistance to chloroquine versus poor response to standard primaquine schedules are discussed. The recent recommendations of adopting a schedule of 6 mg/kg as a total dose of primaquine proved in our cases to be effective in obtaining a radical cure of the infection.
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Malária Vivax/tratamento farmacológico , Primaquina/uso terapêutico , Cloroquina/uso terapêutico , Resistência a Medicamentos , Quimioterapia Combinada , Guatemala , Humanos , Masculino , Quinina/uso terapêuticoRESUMO
The purpose of this article is to describe a research project carried out in Virginia, Maryland, Delaware and Pennsylvania. The main objective was to find out the continuing education needs of the staff implementing Primary Health Care (phc) programs developed with Mexican migrant workers. The methodology was based on applied research techniques. It was divided into two stages. The first stage was an interview which was applied to the coordinators of three programs: medical care, health education and sexually transmitted diseases. The second part of the methodology was to design a continuing education course with the input of the first stage. The course was implemented in the School of Public Health of Mexico in 1990. It had three main components: sociology and health in Mexico; health programmes in Mexico, and traditional medicine. The course also included a set of visits to clinics, hospitals and curanderos. The course has generated a group of scholars who are planning projects in this field to define the health needs of the migrant Mexican population in that area and the impact in Mexico. The course is also part of the regular Continuing Education Programme of the School of Public Health of Mexico now.