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1.
Aging Health Res ; 2(1): 100053, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35018357

RESUMO

The novel coronavirus disease (COVID-19) has had an incisive effect on residents living in long-term care facilities (LTCFs). Local governments have introduced restrictive measures because of the danger posed by this virus. One increasing negative effect of these implementations among residents living in LTCFs is their subjective feelings of loneliness. This study assumed that these measures weighed heavily particularly on residents living in LTCFs, as this group of older people could not decide for themselves whether or how they should be implemented. Thus, this study investigated the retrospectively reported subjective loneliness of residents living in LTCFs. On a large-scale Swiss survey (N = 828; mean age: 87.78, 75% female), residents of 22 LTCFs filled out a questionnaire on their subjective feelings of loneliness during the pandemic. The retrospective loneliness scores of the residents living in LTCFs were found to exceed those reported in other studies focusing on community-dwelling older people. Multivariate regression analyses showed that females, individuals with lower values of joy in life and life satisfaction, and individuals who were not satisfied with the manner in which their care home coped with the COVID-19 measures significantly felt lonelier. Therefore, the subjective feelings of loneliness of residents in LTCFs should be monitored very carefully. As the measures have still not been completely lifted, residents of LTCFs are assumed to still experience social isolation and be at high risk of encountering prolonged feelings of loneliness, which can be detrimental to their mental health and well-being.

2.
J Environ Radioact ; 208-209: 106047, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31526956

RESUMO

As part of an underground gas migration study, two radioactive noble gases (37Ar and 127Xe) and two stable tracer gases (SF6 and PFDMCH) were injected into a historic nuclear explosion test chimney and allowed to migrate naturally. The purpose of this experiment was to provide a bounding case (natural transport) for the flow of radioactive noble gases following an underground nuclear explosion. To accomplish this, soil gas samples were collected from a series of boreholes and a range of depths from the shallow subsurface (3 m) to deeper levels (~160 m) over a period of eleven months. These samples have provided insights into the development and evolution of the subsurface plume and constrained the relative migration rates of the radioactive and stable gas species in the case when the driving pressure from the cavity is low. Analysis of the samples concluded that the stable tracer SF6 was consistently enriched in the subsurface samples relative to the radiotracer 127Xe, but the ratios of SF6 and 37Ar remained similar throughout the samples.


Assuntos
Gases Nobres/análise , Armas Nucleares , Monitoramento de Radiação , Radioatividade , Explosões , Nevada , Medidas de Segurança
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 475-481, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31945941

RESUMO

Lactate and pH values in human blood are important physiological parameters that can reflect serious pathological states as sepsis or hypoxia. In this study we demonstrate that we can determine lactate and pH values from blood samples by Raman spectroscopy combined with multivariate analysis at medically relevant resolution and reliability. The method prepares the base for new real-time in vivo analytics for a number of pathological cases and physiological control in competitive sports. We demonstrate the capability to resolve pH variations of 0.04 and lactate concentrations of 0.20 mM ex vivo.


Assuntos
Análise Espectral Raman , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico , Reprodutibilidade dos Testes , Sepse
4.
Ophthalmologe ; 115(10): 818-825, 2018 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-29679132

RESUMO

The use of self-reported vision is an integral part of most population surveys and is primarily used for healthcare monitoring. Since the patient's assessment is not always consistent with the objectively measured clinical parameters, the majority of the literature looks critically at the adequacy of self-reported vision, particularly with respect to answering epidemiological questions; however, it is often misunderstood that self-reported vision measures far more than the directly derived information show. This article shows the complexity of self-reported vision and discusses the importance of health services research and practice, with a special focus on the topic of vision in old age. From the explanations it becomes clear that the self-estimation of vision by a person is determined by various factors apart from the pure organ function and that the need for action and diagnostic conclusions can only be derived from self-reports. This is essential if vision is to be understood as a multifactorial condition and empirically practiced using different survey instruments. The article shows that self-reported vision is a good indicator of the quality of care in its entirety.


Assuntos
Pesquisa sobre Serviços de Saúde , Visão Ocular , Humanos , Autorrelato , Inquéritos e Questionários
5.
RSC Adv ; 8(26): 14713-14721, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-35540740

RESUMO

Polyamide 6/modified silica composite materials have been prepared by a coupled polymerization procedure. For this purpose, the three-component-system we presented in a previous publication, consisting of ε-aminocaproic acid (ε-ACA), ε-caprolactam (ε-CL), and 1,1',1'',1'''-silanetetrayltetrakis-(azepan-2-one) (Si(ε-CL)4), has been combined with other silicon monomers with one or two methyl groups (MeSi(ε-CL)3 and Me2Si(ε-CL)2). The simultaneous polymerization of ε-CL and silicon monomers leads to the in situ formation of silica/polysiloxane particles and the surrounding polyamide 6 matrix in one step. Moreover, 3-aminopropyltriethoxysilane has been added to the three-component-system to achieve covalent bonding between organic and inorganic phases and to inhibit agglomeration of the silica particles. Chemical structures and morphologies of the composites have been investigated by solid-state NMR and FTIR spectroscopy as well as electron microscopy and SEC measurements. Structural effects on thermal properties have been studied by DSC and TGA measurements.

6.
RSC Adv ; 8(55): 31673-31681, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-35548201

RESUMO

Organic-inorganic hybrid materials with urethane functionalities were obtained by simultaneous twin polymerization of twin prepolymers in combination with the ideal twin monomer 2,2'-spirobi[4H-1,3,2-benzodioxasiline]. The twin prepolymers consist of a urethane-based prepolymer with reactive terminal groups which can react during the twin polymerization process. Nanostructured hybrid materials with integrated dialkylsiloxane crosslinked urethane structures, phenolic resin and SiO2 are obtained in a one pot process. The effects of the polymerization temperature as well as those of various catalysts and reagent ratios on the polymerization behavior were investigated. The molecular structures of the obtained materials were determined by 13C- and 29Si-{1H}-CP-MAS NMR spectroscopies. HAADF-STEM-measurements were performed to prove the distribution of silicon in the hybrid material.

7.
Anaesthesist ; 66(11): 858-861, 2017 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-28887627

RESUMO

A previously healthy 60-year-old patient presented to the emergency department with severe headache, altered personality and fever. He was treated for bacterial meningitis with delirium of unknown cause but presumed to be due to alcohol withdrawal. Despite receiving the antibiotic therapy regimen recommended for bacterial meningitis the patient's condition rapidly deteriorated with profound delirium and tachypnea. The intensivist who was consulted immediately suspected sepsis-associated organ failure and admitted the patient to the intensive care unit (ICU). The blood culture was positive for Listeria. After 10 days the patient could be discharged from the ICU and ultimately recovered completely. In patients presenting with unexplained delirium or altered personality the suspicion of septic encephalopathy should always be considered. They should be admitted to the ICU and sepsis treatment should be initiated without delay.


Assuntos
Delírio/diagnóstico , Sepse/diagnóstico , Antibacterianos/uso terapêutico , Encefalopatias/diagnóstico , Encefalopatias/etiologia , Cuidados Críticos , Humanos , Masculino , Meningite por Listeria/tratamento farmacológico , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/diagnóstico , Insuficiência de Múltiplos Órgãos/etiologia , Choque Séptico/tratamento farmacológico
8.
J Environ Radioact ; 178-179: 28-35, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28755564

RESUMO

Pacific Northwest National Laboratory reports on the detection of 39Ar at the location of an underground nuclear explosion on the Nevada Nuclear Security Site. The presence of 39Ar was not anticipated at the outset of the experimental campaign but results from this work demonstrated that it is present, along with 37Ar and 85Kr in the subsurface at the site of an underground nuclear explosion. Our analysis showed that by using state-of-the-art technology optimized for radioargon measurements, it was difficult to distinguish 39Ar from the fission product 85Kr. Proportional counters are currently used for high-sensitivity measurement of 37Ar and 39Ar. Physical and chemical separation processes are used to separate argon from air or soil gas, yielding pure argon with contaminant gases reduced to the parts-per-million level or below. However, even with purification at these levels, the beta decay signature of 85Kr can be mistaken for that of 39Ar, and the presence of either isotope increases the measurement background level for the measurement of 37Ar. Measured values for the 39Ar measured at the site ranged from 36,000 milli- Becquerel/standard-cubic-meter-of-air (mBq/SCM) for shallow bore holes to 997,000 mBq/SCM from the rubble chimney from the underground nuclear explosion.


Assuntos
Argônio/análise , Armas Nucleares , Monitoramento de Radiação , Poluentes Radioativos/análise , Nevada
9.
Appl Radiat Isot ; 126: 185-187, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28318931

RESUMO

Low-background lead for radiation measurement shielding is often assayed for 210Pb to ensure acceptable backgrounds. Samples of lead assayed with a germanium spectrometer calibrated for bremsstrahlung-based assay of 210Pb provide a view into the 210Pb content of commercial lead in the U.S. (other than stockpiled Doe Run lead). Results suggest that the loss of lead smelting in the U.S. has eliminated the traditional supply of "low background" lead (~30Bqkg-1), and indicate current commercial supplies contain roughly an order of magnitude higher 210Pb levels.

10.
Appl Radiat Isot ; 126: 243-248, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28236555

RESUMO

This paper describes the generation of 39Ar, via reactor irradiation of potassium carbonate, followed by quantitative analysis (length-compensated proportional counting) to yield two calibration standards that are respectively 50 and 3 times atmospheric background levels. Measurements were performed in Pacific Northwest National Laboratory's shallow underground counting laboratory studying the effect of gas density on beta-transport; these results are compared with simulation. The total expanded uncertainty of the specific activity for the ~50× 39Ar in P10 standard is 3.6% (k=2).

11.
Appl Opt ; 55(15): 4261-9, 2016 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-27411158

RESUMO

We present a novel bimodal endoscopic imaging probe that can simultaneously provide full-field white-light video microscopy and confocal optical coherence tomography (OCT) depth scans. The two modalities rely on spectrally separated optical paths that run partially in parallel through a micro-optical bench system, which has a cross-section of only 2 mm×2.76 mm and is realized via standard silicon micromachining techniques. With a numerical aperture of 0.061, the video modality has a resolution and field of view of 9.3 and 1240 µm×1080 µm, respectively. The resolution is limited by the pixel spacing of the coherent fiber bundle, which relays the acquired image from the distal to the proximal end. A custom-designed diffractive optical element placed within the video imaging path significantly improves the image contrast by up to 45% in the medium frequency range. The OCT modality is optimized for 830 nm center wavelength, and works in a confocal arrangement with an NA of 0.018. It provides single-point depth probing at the center of the video image with a lateral resolution of 20 µm. Through its compact footprint and enhanced functionality, the probe can provide depth-resolved guiding capability for existing laparoscopes and represents a major step toward a new class of multimodal endoscopic imaging probes.

12.
J Environ Radioact ; 155-156: 122-129, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26990077

RESUMO

Simultaneous measurement of tritium and (14)C would provide an added tool for tracing organic compounds through environmental systems and is possible via beta energy spectroscopy of sample-derived methane in internal-source gas proportional counters. Since the mid-1960's atmospheric tritium and (14)C have fallen dramatically as the isotopic injections from aboveground nuclear testing have been diluted into the ocean and biosphere. In this work, the feasibility of simultaneous tritium and (14)C measurements via proportional counters is revisited in light of significant changes in both the atmospheric and biosphere isotopics and the development of new ultra-low-background gas proportional counting capabilities for small samples (roughly 50 cc methane). A Geant4 Monte Carlo model of a Pacific Northwest National Laboratory (PNNL) proportional counter response to tritium and (14)C is used to analyze small samples of two different methane sources to illustrate the range of applicability of contemporary simultaneous measurements and their limitations. Because the two methane sources examined were not sample size limited, we could compare the small-sample measurements performed at PNNL with analysis of larger samples performed at a commercial laboratory. These first results show that the dual-isotope simultaneous measurement is well matched for methane samples that are atmospheric or have an elevated source of tritium (i.e. landfill gas). However, for samples with low/modern tritium isotopics (rainwater), commercial separation and counting is a better fit.


Assuntos
Radioisótopos de Carbono/análise , Metano/análise , Monitoramento de Radiação/métodos , Trítio/análise , Gases/análise , Modelos Teóricos , Instalações de Eliminação de Resíduos , Purificação da Água
13.
Appl Radiat Isot ; 108: 92-99, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26720259

RESUMO

Development of ultra low background gas proportional counters has made the contribution from naturally occurring radioactive isotopes - primarily α and ß activity in the uranium and thorium decay chains - inconsequential to instrumental sensitivity levels when measurements are performed in above ground surface laboratories. Simple lead shielding is enough to mitigate against gamma rays as gas proportional counters are already relatively insensitive to naturally occurring gamma radiation. The dominant background in these surface laboratory measurements using ultra low background gas proportional counters is due to cosmic ray generated muons, neutrons, and protons. Studies of measurements with ultra low background gas proportional counters in surface and underground laboratories as well as radiation transport Monte Carlo simulations suggest a preferred conceptual design to achieve the highest possible sensitivity from an array of low background gas proportional counters when operated in a surface laboratory. The basis for a low background gas proportional counter array and the preferred shielding configuration is reported, especially in relation to measurements of radioactive gases having low energy decays such as (37)Ar.

14.
Appl Radiat Isot ; 109: 430-434, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26701655

RESUMO

Argon-37 is an environmental signature of an underground nuclear explosion. Producing and quantifying low-level (37)Ar standards is an important step in the development of sensitive field measurement instruments. This paper describes progress at Pacific Northwest National Laboratory in developing a process to generate and quantify low-level (37)Ar standards, which can be used to calibrate sensitive field systems at activities consistent with soil background levels. This paper presents a discussion of the measurement analysis, along with assumptions and uncertainty estimates.

15.
Opt Express ; 23(19): 24525-36, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26406656

RESUMO

We describe a novel approach for fabricating customized convex as well as concave micro-lenses using substrates with sophisticated pinning architecture and utilizing a drop-on-demand jet printer. The polymeric lens material deposited on the wafer is cured by UV light irradiation yielding lenses with high quality surfaces. Surface shape and roughness of the cured polymer lenses are characterized by white light interferometry. Their optical quality is demonstrated by imaging an USAF1951 test chart. The evaluated modulation transfer function is compared to Zemax simulations as a benchmark for the fabricated lenses.

16.
Sci Technol Adv Mater ; 16(1): 015003, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27877753

RESUMO

Polymeric structures with integrated, functional microelectrical mechanical systems (MEMS) elements are increasingly important in various applications such as biomedical systems or wearable smart devices. These applications require highly flexible and elastic polymers with good conductivity, which can be embedded into a matrix that undergoes large deformations. Conductive polydimethylsiloxane (PDMS) is a suitable candidate but is still challenging to fabricate. Conductivity is achieved by filling a nonconductive PDMS matrix with conductive particles. In this work, we present an approach that uses new mixing techniques to fabricate conductive PDMS with different fillers such as carbon black, silver particles, and multiwalled carbon nanotubes. Additionally, the electrical properties of all three composites are examined under continuous mechanical stress. Furthermore, we present a novel, low-cost, simple three-step molding process that transfers a micro patterned silicon master into a polystyrene (PS) polytetrafluoroethylene (PTFE) replica with improved release features. This PS/PTFE mold is used for subsequent structuring of conductive PDMS with high accuracy. The non sticking characteristics enable the fabrication of delicate structures using a very soft PDMS, which is usually hard to release from conventional molds. Moreover, the process can also be applied to polyurethanes and various other material combinations.

17.
Chem Commun (Camb) ; 50(68): 9753-6, 2014 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-25023389

RESUMO

Amino-functionalized organic-inorganic hybrid materials with a narrow distributed nanostructure of 2-4 nm in size were obtained by means of a template-free and non-aqueous procedure. Simultaneous twin polymerization of novel amino group containing twin monomers with 2,2'-spirobi[4H-1,3,2-benzodioxasiline] has been applied for this purpose. The amino groups of the organic-inorganic hybrid material are useful for post derivatization.

18.
Opt Express ; 22(11): 13343-50, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24921528

RESUMO

A novel type of integrated refractive-diffractive varifocal membrane lens is designed and analyzed by wave-optical methods. In contrast to other hybrid devices, the diffractive microstructure is directly imprinted onto the soft deflecting membrane, allowing for a high level of integration. Elastic deformation is taken into account by mechanical simulations with the finite element method (FEM). We show, that the superimposed structure can considerably suppress chromatic and spherical aberration. Furthermore, our algorithm is successfully applied to design a confocal hyperspectral lens.

19.
Drug Alcohol Depend ; 134: 185-193, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24176199

RESUMO

BACKGROUND: In a recent paper, we reported the efficacy of a modular cognitive-behavioral intervention for treating adolescents and adults with cannabis use disorders (CUD). In this study, we examine the outcome of this intervention after translating it into clinical practice. METHODS: A multi-site, randomized controlled trial of 279 treatment seekers with ICD-10 cannabis use disorders aged 16- 63 years was conducted in 11 outpatient addiction treatment centers in Germany. Patients were randomly assigned to an Active Treatment (AT, n=149) or Delayed Treatment Control (DTC, n=130). Treatment consisted of 10 sessions of fully manualized individual psychotherapy that combined Cognitive-Behavioral Therapy, Motivational EnhancementTherapy and problem-solving training. Assessments were conducted at baseline, during each therapy session, at post-treatment and at three and six month follow-ups. RESULTS: At post assessment 53.3% of AT patients reported abstinence (46.3% negative urine screenings) compared to 22% of DTC patients (17.7% negative drug screenings) (p<0.001, Intention-to-treat analysis). AT patients improved in the frequency of cannabis use, number of cannabis dependence criteria, severity of dependence, as well as number and severity of cannabis-related problems. Effect sizes were moderate to high. While abstinence rates in the AT group decreased over the 3-month (negative urine screenings: 32.4%) and 6-month (negative urine screenings: 35.7%) follow-up periods, the effects in secondary outcomes were maintained. CONCLUSIONS: The intervention can successfully be translated to and applied in clinical practice. It has the potential to improve access to evidence-based care for chronic CUD patients.


Assuntos
Assistência Ambulatorial/métodos , Abuso de Maconha/epidemiologia , Abuso de Maconha/terapia , Centros de Tratamento de Abuso de Substâncias/métodos , Pesquisa Translacional Biomédica/métodos , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Abuso de Maconha/diagnóstico , Pessoa de Meia-Idade , Sistema de Registros , Método Simples-Cego , Resultado do Tratamento , Adulto Jovem
20.
Appl Radiat Isot ; 81: 179-83, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23597417

RESUMO

Pacific Northwest National Laboratory (PNNL) is developing a capability to measure the absolute activity concentration of gaseous radionuclides using length-compensated proportional-counting. This capability will enable the validation of low-level calibration standards for use in PNNL's new shallow underground laboratory. Two sets of unequal length proportional counters have been fabricated; one set has been fabricated using ultra-low background (ULB) electroformed copper and a second set fabricated from Oxygen-Free High-Conductivity Copper (OFHC).


Assuntos
Gases/química , Radioisótopos/análise , Contagem de Cintilação/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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