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1.
HardwareX ; 8: e00136, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35498252

RESUMO

Understanding the spatial variability of gaseous carbon flux at a landscape scale requires intensive monitoring campaigns necessitating significant and perhaps prohibitive financial investment. Commercially available CO2 sensors may only partially fulfil the requirements of the researcher, thereby generating inadequate data. In this context we present the fully replicable designs for a low-cost, microcontroller-based gaseous CO2 concentration data logger suitable for field deployment at scale. It demonstrates a post-calibration accuracy of 96-99% and large onboard data storage for data collected at user-defined intervals. The sensor can be powered via USB or batteries, assembled by novice users, and produced for approximately £155. Post-calibration it was used to measure CO2 evasion from a peatland stream, environments known to be spatially and temporally variable CO2 sources, although potential applications are much wider in scope. The proliferation of low-cost, open-source, and user-made sensors in physical sciences could allow researchers to answer questions previously unanswerable due to the limitations of existing proprietary equipment. We encourage other research teams to use and adapt this design for a range of purposes and research questions beyond carbon processing in peatlands.

2.
Phys Med Biol ; 64(7): 075014, 2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30875697

RESUMO

The current study evaluates dosimetric and spectral effects when platinum (Pt)-based chemotherapeutics and less toxic tungstophosphoric-acid (TPA) organometallics are present during x-ray radiotherapy. We hypothesize that the use of high energy photon beams (i.e. 18 MV) will increase absorbed dose due to increased pair production from high-Z elements and thus result in additional tumor cell kill. EGSnrc code was used to examine the contribution of pair production to dose in the presence of the high-Z material (TPA, Pt mixtures and tungsten, W) as a function of beam energy. Variables included different concentrations (100 µmolar, 1 mmolar), depths (5 mm, 10 cm), thicknesses (5 mm, 5 cm) and energies (6, 18 MV). Overall, for the deeper depth, the 511 keV photon fluence increase was up 31% (18 MV-1 mmolar) while at 6 MV it was between 10%-11% depending on the concentration. For the shallower depth, 18 MV fluence increase was up 14.6% (1 mmolar) and 18.6% (1 mmolar) for the 6 MV. The dose enhancement effect due to pair production was up 25%-30% and a total 33%-58% depending on the depth. The benefit related to pair production was more for 18 MV and under conditions that simulated a realistic clinical setup. While part of the effect could be attributed to photoabsorption, a significant contribution of dose could result from pair production. Experimental clonogenic survival assay was consistent with the theory in that the low dose shoulder region of a cell survival curve was reduced using TPA and 18 MV compared with TPA and 6 MV or compared with no TPA and 18 MV; RBE was approximately 2 at the dose commonly used in conventional fractionated clinical radiotherapy. This suggests a potential new strategy for dose enhancement based on pair production using higher energy beamlines.


Assuntos
Método de Monte Carlo , Compostos Organometálicos/química , Imagens de Fantasmas , Fótons/uso terapêutico , Planejamento da Radioterapia Assistida por Computador/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Células A549 , Humanos , Radiometria , Dosagem Radioterapêutica
3.
Br J Oral Maxillofac Surg ; 56(6): 536-539, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29908705

RESUMO

To examine associations between socioeconomic status and the extent to which patients with cancer of the head and neck expressed concerns to surgeons during routine follow-up clinics, we analysed audio recordings of 110 consultations with one consultant. We used the Verona Coding Definitions of Emotional Sequences (VRCoDES) to measure communication between the doctor and the patient, and grouped the English indices of multiple deprivation (IMD) 2015 scores into deciles to compare the VRCoDES with socioeconomic status. There were no significant correlations between IMD decile and the number and type of cues and concerns, or the type of response by the consultant, but there was a positive correlation between IMD decile and duration of appointment (r=0.288, p<0.01). When the duration of appointment was controlled for, there was a negative correlation between IMD decile and number of cues and concerns (r=-0.221, p<0.05). These findings question the assumption that socioeconomic status is associated with a patient's willingness to express concerns. Shorter consultations suggest that less time is spent responding to their concerns or building a rapport. Clinicians might find it advantageous to adopt strategies that will improve their understanding of these patients and help them to communicate more effectively.


Assuntos
Comunicação , Neoplasias de Cabeça e Pescoço/psicologia , Relações Médico-Paciente , Classe Social , Adulto , Idoso , Idoso de 80 Anos ou mais , Emoções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos
4.
Annu Rev Phytopathol ; 41: 53-75, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12704217

RESUMO

Tomato spotted wilt caused by thrips-vectored tomato spotted wilt virus (TSWV) is a very serious problem in peanut (Arachis hypogaea L.) production. TSWV and the thrips Frankliniella fusca and Frankliniella occidentalis, which vector the virus, present a difficult and complicated challenge from the perspectives of both epidemiology and disease management. Simply controlling the vector typically has not resulted in control of spotted wilt. No single measure can currently provide adequate control of spotted wilt where severe epidemics occur. However, interdisciplinary investigations have resulted in development of integrated management systems that make use of moderately resistant cultivars and chemical and cultural practices, each of which helps to suppress spotted wilt epidemics. Such systems have been successfully deployed in many areas for minimizing losses to this disease. The development of a spotted wilt risk index has aided greatly in relaying information on the importance of using an integrated approach for managing this disease.


Assuntos
Arachis/virologia , Doenças das Plantas/virologia , Tospovirus/patogenicidade , Tospovirus/isolamento & purificação
5.
Psychiatr Serv ; 52(6): 841-3, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11376239

RESUMO

The author examined variations in the clinical characteristics, costs, utilization, and discharge patterns of adult inpatients who were hospitalized for psychiatric disorders in Maryland state general hospitals in 1998. Administrative discharge data on all 30,121 adult psychiatric patients in the state in 1998 were used to calculate descriptive statistics on elderly (age 65 years and over) and nonelderly (age 19 to 64 years) patients. The most common reasons for hospitalization were substance-related disorders, which affected 25 percent of the patients, and major depressive disorders, which affected 24.6 percent of the patients. After the effects of Medicare's prospective payment system were disregarded, the average cost of treating elderly persons for depression was calculated to be around 80 percent higher than national estimates.


Assuntos
Custos Hospitalares , Hospitais Gerais/estatística & dados numéricos , Transtornos Mentais/economia , Unidade Hospitalar de Psiquiatria/estatística & dados numéricos , Adulto , Idoso , Transtorno Depressivo/economia , Transtorno Depressivo/terapia , Feminino , Serviços de Saúde para Idosos/economia , Hospitais Gerais/economia , Humanos , Tempo de Internação , Masculino , Maryland , Medicare/estatística & dados numéricos , Transtornos Mentais/terapia , Pessoa de Meia-Idade , Unidade Hospitalar de Psiquiatria/economia , Transtornos Relacionados ao Uso de Substâncias/economia , Transtornos Relacionados ao Uso de Substâncias/terapia , Estados Unidos
6.
Plast Reconstr Surg ; 105(3): 919-27; discussion 928-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10724251

RESUMO

Several previous studies have shown that breast implant patients demonstrate a number of differences compared with the general population. However, studies have not compared patients with breast implants with women receiving other types of plastic surgery, of interest because this latter group has been proposed as a comparison group for assessing the long-term health effects experienced by breast implant patients. Questionnaire data obtained from 7447 breast implant patients and 2203 patients with other types plastic surgery were collected during the course of a retrospective cohort study, to determine whether implant patients demonstrate different characteristics compared with a more restricted group of patients. In contrast to previous investigations that compared implant patients with the general population, distinctive differences with respect to family income, number of pregnancies, alcohol consumption, cigarette smoking, or histories of previous gynecologic operations or operations for benign breast disease were not found. However, implant patients were significantly more likely than other plastic surgery patients to be white, have low levels of education, have early ages at first birth, be thin, and be screened frequently for breast disease. Furthermore, implant patients reported somewhat greater use of exogenous hormones and familial histories of rheumatoid arthritis. These results support the notion that other plastic surgery patients are a more appropriate comparison group than women in the general population for studies of the health effects of breast implants; however, there continue to be distinctive characteristics possessed by breast implant patients, which need to be taken into account in an assessment of what disease effects can be uniquely attributed to silicone breast implants.


Assuntos
Implante Mamário/estatística & dados numéricos , Cirurgia Plástica/estatística & dados numéricos , Adulto , Consumo de Bebidas Alcoólicas , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , História Reprodutiva , Estudos Retrospectivos , Géis de Silicone , Fumar , Fatores Socioeconômicos , Inquéritos e Questionários
7.
Harv Bus Rev ; 77(3): 72-82, 208, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10387579

RESUMO

In turbulent markets, businesses and opportunities are constantly falling out of alignment. New technologies and emerging markets create fresh opportunities. Converging markets produce more. And of course, some markets fade. In this landscape of continuous flux, it's more important to build corporate-level strategic processes that enable dynamic repositioning than it is to build any particular defensible position. That's why smart corporate strategists use patching, a process of mapping and remapping business units to create a shifting mix of highly focused, tightly aligned businesses that can respond to changing market opportunities. Patching is not just another name for reorganizing; patchers have a distinctive mindset. Traditional managers see structure as stable; patching managers believe structure is inherently temporary. Traditional managers set corporate strategy first, but patching managers keep the organization focused on the right set of business opportunities and let strategy emerge from individual businesses. Although the focus of patching is flexibility, the process itself follows a pattern. Patching changes are usually small in scale and made frequently. Patching should be done quickly; the emphasis is on getting the patch about right and fixing problems later. Patches should have a test drive before they're formalized but then be tightly scripted after they've been announced. And patching won't work without the right infrastructure: modular business units, fine-grained and complete unit-level metrics, and companywide compensation parity. The authors illustrate how patching works and point out some common stumbling blocks.


Assuntos
Comércio/organização & administração , Inovação Organizacional , Administração de Linha de Produção , Comércio/economia , Competição Econômica , Marketing de Serviços de Saúde/organização & administração , Cultura Organizacional , Técnicas de Planejamento , Estados Unidos
8.
Harv Bus Rev ; 76(2): 59-69, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10177867

RESUMO

Most companies change in reaction to events such as moves by the competition, shifts in technology, or new customer demands. In fairly stable markets, "event pacing" is an effective way to deal with change. But successful companies in rapidly changing, intensely competitive industries take a different approach. They change proactively, through regular deadlines. The authors call this strategy time pacing. Like a metronome, time pacing creates a rhythm to which managers can synchronize the speed and intensity of their efforts. For example, 3M dictates that 25% of its revenues every year will come from new products, Netscape introduces a new product about every six months, and Intel adds a new fabrication facility to its operations approximately every nine months. Time pacing creates a relentless sense of urgency around meeting deadlines and concentrates people on a common set of goals. Its predictability also provides people with a sense of control in otherwise chaotic markets. The authors show how companies such as Banc One, Cisco Systems, Dell Computer, Emerson Electric, Gillette, Intel, Netscape, Shiseido, and Sony implement the two essentials of time pacing. The first is managing transitions--the shift, for example, from one new-product-development project to the next. The second is setting the right rhythm for change. Companies that march to the rhythm of time pacing build momentum, and companies that effectively manage transitions sustain that momentum without missing important beats.


Assuntos
Comércio/organização & administração , Administração de Linha de Produção/métodos , Comércio/economia , Sistemas Computacionais/tendências , Competição Econômica , Renda , Inovação Organizacional , Objetivos Organizacionais , Gerenciamento do Tempo , Estados Unidos
9.
Health Technol Assess ; 1(8): i-iv, 1-83, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9483159

RESUMO

OBJECTIVES: To undertake a systematic review of the effectiveness of preschool vision screening. To provide evidence on which decisions about the future provision of this service can be made. To indicate areas for further research. STUDY SELECTION: The Centre for Reviews and Dissemination guidelines for systematic reviews were used. The research questions were formulated using the Wilson and Jungner criteria for evaluating screening programmes. They concerned prevalence, natural history, disability, treatment and screening in relation to three target conditions: amblyopia, refractive errors and squints which are not cosmetically obvious. Studies were considered for inclusion according to pre-determined criteria for the age group studied, the outcomes measured and the study design. The following types of study design were considered: cross-sectional studies of prevalence, cohort studies of natural history, any type of study (e.g., cross-sectional surveys, case-series, qualitative studies) of disability attributable to a target condition, controlled trials, observational studies and audits of screening programmes, and prospective controlled trials of treatment. DATA SOURCES: The following electronic databases were searched: Biological Abstracts, CINAHL, Embase, ERIC, IAC Health Periodicals, IAPV, Medline, Psychlit, Science Citation Index, System for Information on Grey Literature in Europe, DHSS-Data, Faculty of Public Health Medicine Database of Dissertations, Index of Scientific and Technical Proceedings, Dissertation Abstracts, Index of Theses, NHS Research Register, Public Health Information Sharing Database. A limited amount of handsearching was undertaken. Reference lists were scanned to identify other relevant studies, and requests for unpublished data were made to people working in the field. DATA EXTRACTION: Data was extracted by the first author and then checked by the second. DATA SYNTHESIS: Quantitative analysis was undertaken where possible. Qualitative analysis was performed where studies were too heterogeneous for the data to be combined, or for research questions that were not suitable for quantitative synthesis. RESEARCH FINDINGS: The electronic search yielded over 5000 references, and over 500 abstracts were downloaded from the databases for further scrutiny. A total of 85 studies were included in the main analysis. PREVALENCE: No studies were found with the primary aim of establishing the prevalence of visual defects in preschool children. Data from studies of screening programmes report a range of yields for all the target conditions combined of 2.4-6.1%. NATURAL HISTORY: No studies designed with the intention of documenting the natural history of the target conditions in children aged 3 or 4 years were found. Other studies that provide some natural history data suggest that mild degrees of amblyopia may resolve spontaneously. In the absence of information about natural history it is impossible to estimate the effect of treatment from studies without a control group that was not treated. DISABILITY: A total of 21 studies exploring disability in relation to the target conditions were included. The literature provides a reasonable basis for generating plausible hypotheses about the ways in which the target conditions might disable people, but is insufficient to draw any firm conclusions about their impact on quality of life. The research to date is not sufficient to determine appropriate outcomes for controlled trials of treatment. TREATMENT: Five randomised controlled trials of treatment and six prospective controlleld trials without randomisation were found. No studies compared treatment with no treatment. Most of the studies were methodologically flawed.(ABSTRACT TRUNCATED)


Assuntos
Oftalmopatias/prevenção & controle , Seleção Visual/organização & administração , Pré-Escolar , Análise Custo-Benefício , Oftalmopatias/economia , Oftalmopatias/epidemiologia , Oftalmopatias/fisiopatologia , Oftalmopatias/terapia , Humanos , Sensibilidade e Especificidade , Avaliação da Tecnologia Biomédica , Resultado do Tratamento , Reino Unido/epidemiologia
11.
Blood ; 81(8): 2031-5, 1993 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-7682454

RESUMO

Hematopoietic growth factors have been used to accelerate engraftment after bone marrow transplantation and to "mobilize" peripheral blood progenitor cells (PBPC). We report on the data in 85 consecutive patients with Hodgkin's disease who were treated in a single institution using different methods to obtain PB progenitor cells. Use of granulocyte colony-stimulating factor for mobilization resulted in a significantly accelerated time to recovery of granulocytes (10 days v 12 days, P < .01) when compared with "nonmobilized" PBPC recipients. Similarly, use of mobilized PBPC resulted in a significantly accelerated time to platelet engraftment (13 days v 30 days, P < .001) when compared with "nonmobilized" recipients. Moreover, there was a statistically significant difference in total costs in favor of the group receiving "mobilized" PBPC.


Assuntos
Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Granulócitos/patologia , Doença de Hodgkin/tratamento farmacológico , Transplante de Células-Tronco , Adolescente , Adulto , Remoção de Componentes Sanguíneos , Custos e Análise de Custo , Feminino , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Granulócitos/transplante , Doença de Hodgkin/sangue , Doença de Hodgkin/cirurgia , Humanos , Macrófagos/transplante , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas
12.
W V Med J ; 88(11): 501-2, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1481525
13.
BMJ ; 303(6813): 1291-4, 1991 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-1747671

RESUMO

OBJECTIVE: To see if there were differences in referral rates and abnormalities detected from two areas that were operating different preschool vision screening programmes. DESIGN: Cohort study using case notes of referrals. SETTING: Community based secondary referral centres in the county of Avon. PATIENTS: 263 referrals from a child population of 7105 in Southmead district, an area that used orthoptists as primary vision screeners; 111 referrals from a child population of 2977 in Weston-super-Mare, an area that used clinical medical officers for screening. MAIN OUTCOME MEASURES: Amblyopia and squint detection rates, together with false positive referral rates. RESULTS: The amblyopia detection rate in Southmead district was significantly higher than in Weston-super-Mare (11/1000 children v 5/1000), as was the detection rate of squint (11/1000 v 3/1000). However, the false positive referral rate from Southmead was significantly lower than that from Weston-super-Mare (9/1000 v 23/1000). CONCLUSION: Preschool vision screening using orthoptists as primary screeners offers a more effective method of detecting visual abnormalities than using clinical medical officers.


Assuntos
Ambliopia/prevenção & controle , Serviços de Saúde da Criança , Estrabismo/prevenção & controle , Seleção Visual/métodos , Pré-Escolar , Estudos de Coortes , Custos e Análise de Custo , Inglaterra , Feminino , Humanos , Lactente , Masculino , Ortóptica , Encaminhamento e Consulta , Seleção Visual/economia , Recursos Humanos
15.
Risk Anal ; 7(3): 285, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3685537

Assuntos
Risco , Humanos
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