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1.
HEC Forum ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850508

RESUMO

Bioethical dilemmas can emerge in research and clinical settings, from end-of-life decision-making to experimental therapies. The COVID-19 pandemic raised serious ethical challenges for healthcare organizations, highlighting the need to conduct needs assessments of the bioethics infrastructures of healthcare organizations. Clinical ethics committees (CECs) also create equitable policies, train staff on ethics issues, and play a consultative role in resolving the difficulty of complex individual cases. The main objective of this project was to conduct a needs assessment of the bioethics infrastructure within a comprehensive hospital system. A cross-sectional anonymous online survey, including quantitative and qualitative formatted questions. The survey was sent to five key leaders from the organization's hospitals. Survey questions focused on the composition, structure, function, and effectiveness of their facilities' bioethics infrastructure and ethics-related training and resources. Positive findings included that most facilities have active CECs with multidisciplinary membership; CECs address critical issues and encourage team members to express clinical ethics concerns. Areas of concern included uncertainty about how CECs function and the process for resolving clinical ethics dilemmas. Most reported no formal orientation process for CEC members, and many said there was no ongoing ethics education process. The authors conclude that if CECs are a critical institutional resource where the practice of medicine and mission intersect, having well-functioning ethics committees with trained and oriented members demonstrates an essential commitment to the mission. The survey revealed that more needs to be done to bolster the bioethics infrastructure of this institution.

2.
MMWR Morb Mortal Wkly Rep ; 72(36): 973-978, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37676839

RESUMO

Eight cases of locally acquired, mosquito-transmitted (i.e., autochthonous) Plasmodium vivax malaria, which has not been reported in the United States since 2003, were reported to CDC from state health departments in Florida and Texas during May 18-July 17, 2023. As of August 4, 2023, case surveillance, mosquito surveillance and control activities, and public outreach and education activities continue in both states. U.S. clinicians need to consider a malaria diagnosis in patients with unexplained fever, especially in areas where autochthonous malaria has been recently reported, although the risk for autochthonous malaria in the United States remains very low. Prompt diagnosis and treatment of malaria can prevent severe disease or death and limit ongoing transmission to local Anopheles mosquitoes and other persons. Preventing mosquito bites and controlling mosquitoes at home can prevent mosquitoborne diseases, including malaria. Before traveling internationally to areas with endemic malaria, travelers should consult with a health care provider regarding recommended malaria prevention measures, including potentially taking malaria prophylaxis. Malaria is a nationally notifiable disease; continued reporting of malaria cases to jurisdictional health departments and CDC will also help ensure robust surveillance to detect and prevent autochthonous malaria in the United States.


Assuntos
Surtos de Doenças , Malária , Animais , Humanos , Texas/epidemiologia , Florida/epidemiologia , Malária/epidemiologia , Malária/prevenção & controle , Pessoal de Saúde
3.
Sensors (Basel) ; 23(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38067770

RESUMO

For the maintenance of railways on soft soils, accurate knowledge of the subsoil conditions is essential. Soft soils at shallow depths have high variability; thus, high spatial resolution is required. Spare telecommunication fiber-optic cables, known as dark fiber, can be used as an array of sensors to measure waves generated by running trains, which offers a unique opportunity to characterize shallow soils at high spatial resolution. We used dark fiber to measure seismic waves generated by running trains and implemented a seismic interferometry technique to retrieve surface waves. We evaluated the reliability of selected parts of the recorded signals split as bow waves (the train approaching the fiber), train waves (the train passing alongside the fiber), and tail waves (the train leaving the fiber) to retrieve broad-band surface waves. The analysis was performed in two distinctive zones. Zone I consists of a thick-soft (2.0-6.0 m thickness) layer, and Zone II consists of a thin-soft (less than 2.0 m thickness) layer, both overlaying a "stiffer" sand layer. At Zone I, train waves yielded the best results in revealing the thick-soft layer. At Zone II, the bow waves yielded clear high-frequency energy, revealing the overall soil structure but without identifying the shallow thin-soft layer.

4.
Appl Opt ; 61(3): A10-A21, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35200761

RESUMO

A new, to the best of our knowledge, method for designing a thick-lens achromatic doublet based on the concept of a caustic surface to correct both third- and fifth-order spherical aberration is presented. We consider two different wavelengths brought into coincidence at the back focal length instead of the effective focal length as it is usually done, to calculate the radii of curvature assuming predefined values for axial thicknesses and their indices of refraction for both lenses. Alternatively, we apply Taylor's series around the optical axis, and to vanish the approximate caustic surface, we obtain the values for the conic constants, which reduce at third- and fifth-order spherical aberration. Two designs for cemented doublets are provided assuming that the lenses are cemented. Finally, we propose a method to qualitatively test doublet lenses by using null screens, considering to place the detection plane at arbitrary positions.

5.
Opt Express ; 29(15): 23300-23314, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34614598

RESUMO

We have implemented an exact ray trace through a plano-freeform surface for an incident plane wavefront. We obtain two caustic surfaces and provide the critical points related to the ray tracing process. Additionally, we study the propagation of the refracted wavefronts through the plane-curved surface. Finally, by using the Ronchi-Hartmann type null screen and placing the detection plane within the caustic region, we have evaluated the shape of a plano-freeform optical surface under test, obtaining an RMS difference in sagitta value of 6.3 µm.

6.
J Opt Soc Am A Opt Image Sci Vis ; 38(11): 1662-1672, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807028

RESUMO

The aim of this work is threefold. First, following Luneburg and using our own notation, we review the Cartesian ovals. Second, we obtain analytical expressions for the reflecting and refracting surfaces that transform a prescribed smooth two-dimensional wavefront into a spherical one. These results are applied to show that the reflecting surface that connects a plane wavefront to a spherical one is a parabolical surface, and we design a lens, with two freeform surfaces, that transforms a spherical wavefront into another spherical one. These examples show that our equations provide the well-known solution for these problems, which is given by the Cartesian ovals method. Third, we present a procedure to obtain exact expressions for the refracting and reflecting surfaces that connect two given arbitrary wavefronts; that is, by assuming that the optical path length between two points on the prescribed wavefronts is given by the designer the refracting and reflecting surfaces we are looking for are determined by a set of two algebraic equations, which in the general case have to be solved in a numerical way. These general results are applied to compute the analytical expressions for the reflecting and refracting surfaces that transform a parabolical initial wavefront into a plane one.

7.
Soft Matter ; 15(45): 9171-9177, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31709428

RESUMO

Fabrication of polymer polyhedral structures is achieved by first producing origami sheets with dissimilar stiffness levels at their folds and faces via multi-step photolithography. Subsequent capillary folding of the sheets towards permanently folded target shapes is realized by thermally controlling, simultaneously, the compliance of the sheets and the volume of the deposited droplets. This fabrication method allows us to create millimeter and sub-millimeter polyhedral structures with arbitrary levels of folding, to manufacture permanently folded polymer polyhedra using single-material monolayer sheets, and to produce carbon shapes from these carbon-rich polymer polyhedra through pyrolysis.

8.
Appl Opt ; 58(22): 5959-5967, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503913

RESUMO

We study the formation of caustic and wavefront surfaces produced by a tilted plane wavefront propagating through spherical positive lenses. The shape of the caustic surface is a function of the indices of refraction, the geometrical parameters of the lens involved in the process of refraction, and the obliquity angle with respect to the optical axis, as we expect. We provide exact and approximate analytic equations for tangential and sagittal focal surfaces and also for Petzval field curvature considering arbitrary lenses.

9.
Appl Opt ; 56(22): 6244-6254, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29047820

RESUMO

We study the formation of caustic surfaces produced by conic lenses, considering a plane wavefront propagating parallel to the optical axis. The shape of the caustic can be modified by changing the parameters of the lens in such a way that if we are able to vanish the caustic, the optical system produces the sharpest diffraction-limited images. Alternatively, caustic surfaces with a large area can be applied to the design of non-imaging optical systems, with potential applications such as diffusers of light for illumination or solar concentrators. Here, we provide analytic equations for the conic constants, principal surfaces, and caustic surfaces, and also approximations at the third and fifth orders formed by conic lenses, in order to reduce the spherical aberration at these orders.

10.
J Opt Soc Am A Opt Image Sci Vis ; 31(2): 448-59, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24562044

RESUMO

The aim of this work is threefold: first we obtain analytical expressions for the wavefront train and the caustic associated with the refraction of a plane wavefront by an axicon lens, second we describe the structure of the ronchigram when the ronchiruling is placed at the flat surface of the axicon and the screen is placed at different relative positions to the caustic region, and third we describe in detail the structure of the null ronchigrating for this system; that is, we obtain the grating such that when it is placed at the flat surface of the axicon its associated pattern, at a given plane perpendicular to the optical axis, is a set of parallel fringes. We find that the caustic has only one branch, which is a segment of a line along the optical axis; the ronchigram exhibits self-intersecting fringes when the screen is placed at the caustic region, and the null ronchigrating exhibits closed loop rulings if we want to obtain its associated pattern at the caustic region.

11.
J Opt Soc Am A Opt Image Sci Vis ; 30(2): 177-88, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23456052

RESUMO

The aim of the present work is twofold: first we obtain analytical expressions for both the wavefronts and the caustic associated with the light rays reflected by a spherical mirror after being emitted by a point light source located at an arbitrary position in free space, and second, we describe, in detail, the structure of the ronchigrams when the grating or Ronchi ruling is placed at different relative positions to the caustic region and the point light source is located on and off the optical axis. We find that, in general, the caustic has two branches: one is a segment of a line, and the other is a two-dimensional surface. The wavefronts, at the caustic region, have self intersections and singularities. The ronchigrams exhibit closed-loop fringes when the grating is placed at the caustic region.

12.
Cureus ; 15(12): e50341, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38205461

RESUMO

Rapid-onset obesity with hypothalamic dysfunction, hypoventilation, and autonomic dysregulation (ROHHAD) syndrome is a rare disease of concurrent respiratory dysfunction and autonomic dysregulation with endocrine abnormalities. ROHHADNET includes ROHHAD plus coexisting neuroendocrine tumors (NETs). We describe an eight-year-old boy, who originally presented at four years of age with rapid weight gain and hyperhidrosis and who developed mild obstructive sleep apnea (OSA). His clinical course was eventually complicated by hypoxic respiratory failure requiring admission to the pediatric intensive care unit (PICU). Echocardiogram at that time demonstrated dilated cardiomyopathy left ventricular ejection fraction (LVEF) of 28% at time of admission. His respiratory failure persisted despite average volume-assured pressure support (AVAPS) around the clock leading to tracheostomy placement for cardiopulmonary support. He also demonstrated autonomic instability with multiple pituitary hormone deficiencies. Computed tomography (CT) imaging of the abdomen and pelvis demonstrated a presacral soft tissue mass consistent with a tumor of neural crest origin. Daytime somnolence and confusion progressed and a low cerebrospinal fluid hypocretin level revealed a diagnosis of narcolepsy type 1.

13.
Cureus ; 15(10): e47974, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38034271

RESUMO

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited channelopathy. In this review, we summarize the epidemiology, pathophysiology, clinical characteristics, diagnostics, genetic mutations, standard treatment, and the emergence of potential gene therapy. This inherited cardiac arrhythmia presents in a bimodal distribution with no association between sex or ethnicity. Six different CPVT genes have been identified, however, most of the cases are related to a heterozygous, gain-of-function mutation on the ryanodine receptor-2 gene (RyR2) and calsequestrin-2 gene (CASQ2) that causes delayed after-depolarization. The diagnosis is clinically based, seen in patients presenting with syncope after exercise or stress-related emotions, as well as cardiac arrest with full recovery or even sudden cardiac death. Standard treatment relies on beta-blockers, with add-on therapy, flecainide, and cardiac sympathetic denervation as second-line treatments. An implantable cardioverter-defibrillator is indicated for patients who have suffered a cardiac arrest. Potential gene therapy has emerged in the last 20 years and accelerated because of associated viral vector application in increasing the efficiency of prolonged cardiac gene expression. Nevertheless, human trials for gene therapy for CPVT have been limited as the population is rare, and an excessive amount of funding is required.

14.
J Opt Soc Am A Opt Image Sci Vis ; 29(6): 1035-46, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22673435

RESUMO

The aim of this paper is to obtain expressions for the k-function, the wavefront train, and the caustic associated with the light rays refracted by an arbitrary smooth surface after being emitted by a point light source located at an arbitrary position in a three-dimensional homogeneous optical medium. The general results are applied to a parabolic refracting surface. For this case, we find that when the point light source is off the optical axis, the caustic locally has singularities of the hyperbolic umbilic type, while the refracted wavefront, at the caustic region, locally has singularities of the cusp ridge and swallowtail types.

15.
Arthroplast Today ; 13: 93-97, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35106343

RESUMO

Prosthetic failure secondary to bearing fracture remains a potential complication in ceramic-on-ceramic total hip arthroplasty. We report the unusual presentation of a ceramic component fracture of a total hip arthroplasty performed 17 years ago that mimicked a periprosthetic joint infection. This case was managed based on the current guidelines and algorithms recommended for periprosthetic joint infection management. Histologic examination of periprosthetic tissue revealed an adverse inflammatory soft-tissue reaction to the ceramic fragments released from the fracture site. Our case highlights a misleading, inflammatory acute response usually associated with an infectious process corresponding to an adverse soft-tissue reaction. High clinical suspicion and a systematic approach are essential to address these deceiving clinical scenarios.

16.
J Opt Soc Am A Opt Image Sci Vis ; 27(4): 832-45, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20360825

RESUMO

In this work we use the geometrical point of view of the Ronchi test and the caustic-touching theorem to describe the structure of the ronchigrams for a parabolical mirror when the point light source is on and off the optical axis and the grating is placed at the caustic associated with the reflected light rays. We find that for a given position of the point light source the structure of the ronchigram is determined by the form of the caustic and the relative position between the grating and the caustic. We remark that the closed loop fringes commonly observed in the ronchigrams appear when the grating and the caustic are tangent to each other. Furthermore, we find that the caustic locally has singularities of the purse or hyperbolic umbilic type, and the ronchigram obtained when the grating is located at certain specific positions at the caustic locally is of the serpentine type. The main motivation of this work is that nowadays a quantitative analysis of the Ronchi test is applied only when the grating is outside the caustic, and we claim that by working at the caustic, the sensitivity of the Ronchi test will be improved. Therefore, a clear understanding of the properties of the ronchigrams when the grating is placed at the caustic will be needed to extend the Ronchi test to that region.

17.
J Opt Soc Am A Opt Image Sci Vis ; 26(11): 2295-305, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19884924

RESUMO

The aim of the present work is to obtain expressions for both the wavefront train and the caustic associated with the light rays reflected by an arbitrary smooth surface after being emitted by a point light source located at an arbitrary position in free space. To this end, we obtain an expression for the k-function associated with the general integral of Stavroudis to the eikonal equation that describes the evolution of the reflected light rays. The caustic is computed by using the definitions of the critical and caustic sets of the map that describes the evolution of an arbitrary wavefront associated with the general integral. It is shown that the expression for the caustic is the same as that--reported in the literature--obtained by using an exact ray tracing. The general results are applied to a parabolic mirror. For this case, we find that when the point light source is off the optical axis, the caustic locally has singularities of the hyperbolic umbilic type while the reflected wavefront at the caustic region locally has singularities of the cusp ridge and swallowtail types.

18.
Rev. cienc. cuidad ; 21(1): 9-22, 2024.
Artigo em Espanhol | LILACS, BDENF - enfermagem (Brasil), COLNAL | ID: biblio-1553602

RESUMO

Objetivo: Conocer los facilitadores y barreras para el uso de la práctica basada en evidencia (PBE) en profesionales de enfermería que laboran en el área clínica. Método: Estudio cuali-tativo de tipo exploratorio descriptivo, con análisis de discurso, se realizaron 6 grupos focales conformados por 3 a 7 participantes para un total de 32 personas, se utilizó un muestreo inten-cional; en promedio fueron grabados entre 60 a 90 minutos por grupo focal. Para el análisis se empleó la fragmentación, codificación y categorización de las entrevistas obteniendo categorías temáticas, subcategorías y códigos a partir del uso del programa Atlas Ti versión 8. Resultados: El 69 % de los entrevistados respondió que el pregrado o posgrado habían recibido algún tipo de formación en PBE, la principal fuente de información cuando tienen alguna duda en la práctica clínica son los protocolos institucionales o los compañeros con más experiencia. Los facilitado-res identificados en este estudio fueron: tiempo para investigar, formación en PBE, iniciativa, grupos de investigación y compañeros; las barreras fueron: falta de apoyo institucional, poca formación en PBE, falta de tiempo, idioma, desmotivación profesional y el rechazo frente al cambio. Conclusiones: Se describen los facilitadores y barreras que presentan los profesionales de enfermería que laboran en el área clínica. Sin embargo se requieren investigaciones adicion-ales que permitan reconocer el fenómeno desde otras perspectivas en el contexto Colombiano y latinoamericano


Objective: To find out the facilitators and barriers to the use of evidence-based practice (EBP) in nursing professionals working in the clinical area. Method: Qualitative descrip-tive exploratory study, with discourse analysis, 6 focus groups were carried out with 3 to 7 participants for a total of 32, a purposive sampling was used; an average of 60 to 90 minutes were recorded per focus group. For the analysis we used the fragmentation, coding and cate-gorisation of the interviews obtaining thematic categories, subcategories and codes from the use of Atlas Ti version 8. Results: 69 % of the interviewees responded that the undergraduate or postgraduate had received some kind of training in EBP, the main source of information when they have any doubt in clinical practice are the institutional protocols or colleagues with more experience. Facilitators identified in this study were: time to investigate, training in EBP, initiative, research groups and peers; barriers were: lack of institutional support, little training in EBP, lack of time, language, professional demotivation and rejection in the face of change. Conclusions: The facilitators and barriers presented by nursing professionals working in the clinical area are described. However, further research is needed to recognise the phenomenon from other perspectives in the Colombian and Latin American context.


Objetivo: Descobrir os facilitadores e as barreiras ao uso da prática baseada em evidências (PBE) em profissionais de enfermagem que atuam na área clínica. Método: Estudo exploratório descritivo qualitativo, com análise de discurso; foram realizados 6 grupos focais com 3 a 7 participantes, totalizando 32; foi usada uma amostragem intencional; foi registrada uma média de 60 a 90 minutos por grupo focal. Para a análise utilizou-se a fragmentação, codificação e categorização das entrevistas obtendo-se categorias temáticas, subcategorias e códigos a partir da utilização do Atlas Ti versão 8. Resultados: 69% dos entrevistados responderam que a grad-uação ou pós-graduação havia recebido algum tipo de treinamento em PBE, a principal fonte de informação quando têm alguma dúvida na prática clínica são os protocolos institucionais ou colegas com mais experiência. Os facilitadores identificados neste estudo foram: tempo para in-vestigar, treinamento em PBE, iniciativa, grupos de pesquisa e colegas; as barreiras foram: falta de apoio institucional, pouco treinamento em PBE, falta de tempo, idioma, desmotivação profis-sional e rejeição diante de mudanças. Conclusões: São descritos os facilitadores e as barreiras apresentados pelos profissionais de enfermagem que trabalham na área clínica. No entanto, são necessárias mais pesquisas para reconhecer o fenômeno de outras perspectivas no contexto co-lombiano e latino-americano


Assuntos
Prática Clínica Baseada em Evidências , Enfermagem Baseada em Evidências , Enfermeiros Clínicos
19.
Appl Opt ; 47(29): 5500-18, 2008 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-18846193

RESUMO

We use geometrical optics and the caustic-touching theorem to study, in an exact way, the change in the topology of the image of an object obtained by reflections on an arbitrary smooth surface. Since the procedure that we use to compute the image is exactly the same as that used to simulate the ideal patterns, referred to as Ronchigrams, in the Ronchi test used to test mirrors, we remark that the closed loop fringes commonly observed in the Ronchigrams when the grating, referred to as a Ronchi ruling, is located at the caustic place are due to a disruption of fringes, or, more correctly, as disruption of shadows corresponding to the ruling bands. To illustrate our results, we assume that the reflecting surface is a spherical mirror and we consider two kinds of objects: circles and line segments.

20.
Repert. med. cir ; 32(2): 184-189, 2023. graf
Artigo em Espanhol | COLNAL, LILACS | ID: biblio-1526552

RESUMO

Introducción: los docentes de las ciencias de la salud deben desarrollar ciertas capacidades para formar a los profesionales del área en los entornos hospitalarios, para ello deben conocer las dinámicas y comportamientos de los relevos generacionales, así como los avances tecnológicos derivados de la globalización y la importancia de incluirlos como herramientas pedagógicas. Objetivo: responder la pregunta ¿Cómo se puede ser docente en un hospital universitario? Discusión y conclusiones: se construyeron unas propuestas sobre las capacidades que el docente debe desarrollar, como investigar, tener en cuenta un modelo pedagógico, un pensamiento crítico y la capacidad de innovar, para permitir su funcionalidad y poder cumplir su misión en la formación de los futuros profesionales de la salud


Introduction: health sciences teachers must develop certain skills to train health professionals within a hospital environment. To this end, they should be aware of the dynamics and trends of generational differences, as well as the technological advances derived from globalization and the importance of their incorporation as pedagogical tools. Objective: to answer the question: How can one be a teacher in a university hospital? Discussion and conclusions: some proposals were made regarding the skills that teachers should gain, such as carrying out research, following a pedagogical model, applying critical thinking, and having innovation capacity, to allow their functionality and enable the fulfillment of their mission in training future health professionals.


Assuntos
Humanos
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