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1.
Rev Sci Instrum ; 83(10): 10D732, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23126904

RESUMO

The ORION laser facility is one of the UK's premier laser facilities which became operational at AWE in 2010. Its primary mission is one of stockpile stewardship, ORION will extend the UK's experimental plasma physics capability to the high temperature, high density regime relevant to Atomic Weapons Establishment's (AWE) program. The ORION laser combines ten laser beams operating in the ns regime with two sub ps short pulse chirped pulse amplification beams. This gives the UK a unique combined long pulse/short pulse laser capability which is not only available to AWE personnel but also gives access to our international partners and visiting UK academia. The ORION laser facility is equipped with a comprehensive suite of some 45 diagnostics covering optical, particle, and x-ray diagnostics all able to image the laser target interaction point. This paper focuses on a small selection of these diagnostics.

2.
Environ Sci Technol ; 43(22): 8516-21, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20028045

RESUMO

Lead-based paint remains a pervasive problem in U.S. cities, and an increasing problem in the developing world where it is still manufactured and used. Little attention has focused on the factors that increase the release of lead pigment granules from painted surfaces. Nitrogen dioxide (NO(2)) and ozone (O(3)) from transportation emissions in urban environments have the potential to react with and remove polymeric binders in paint, making pigment granules more available for subsequent transfer to hands on contact, or deposition in housedust. Here we show that exposure to NO(2) and O(3) increased the lead in wipe samples of stainless steel surfaces painted with alkyd low gloss solvent lead-based paint by 296% +/- 101 (or 0.24 microg/cm(2)) and 37% +/- 21 (or 0.025 microg/cm(2)), respectively, with corresponding changes in surface morphology indicated by reflectometry and scanning electron microscopy. Lead release from unexposed low gloss acrylic household paints was 40 times greater than comparable solvent based paints. Given that lead-based paint is still manufactured and used in many urban areas of the developing world where O(3) concentrations currently exceed historic U.S. concentrations, the interaction of air pollution with lead painted indoor surfaces may pose greater exposure risks for lead poisoning in children than previously anticipated.


Assuntos
Poluentes Ambientais/química , Chumbo/química , Dióxido de Nitrogênio/química , Ozônio/química , Pintura/análise , Humanos , Intoxicação por Chumbo/prevenção & controle
3.
Indoor Air ; 17(3): 189-203, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17542832

RESUMO

UNLABELLED: In 2001-2003, a team of researchers from the United States and China performed an independent, multidisciplinary review of China's National Improved Stove Program carried out since the 1980s. As part of a 3500-household survey, a subsample of 396 rural households were monitored for particulate matter less than 4 microm (PM(4)) in kitchens and living rooms over 24 h, of which 159 were measured in both summer and winter. Carbon monoxide was measured in a 40% subsample. The results of this indoor air quality (IAQ) component indicate that for nearly all household stove or fuel groupings, PM(4) levels were higher than - and sometimes more than twice as high as - the national PM(10) standard for indoor air (150 microg PM(10)/m(3)). If these results are typical, then a large fraction of China's rural population is now chronically exposed to levels of pollution far higher than those determined by the Chinese government to harm human health. Further, we observed highly diverse fuel usage patterns in these regions in China, supporting the observations in the household survey of multiple stoves being present in many kitchens. Improved stoves resulted in reduced PM(4) from biomass fuel combinations, but still not at levels that meet standards, and little improvement was observed in indoor pollution levels when other unimproved stoves were present in the same kitchen. As many households change fuels according to daily and seasonal factors, resulting in different seasonal concentrations in living rooms and kitchens, assessing health implications from fuel use requires longitudinal evaluation of fuel use and IAQ levels, combined with accurate time-activity information. PRACTICAL IMPLICATIONS: Leaving aside the difficult issue of enforcement, it is uncertain whether Chinese household IAQ standards represent realistic objectives for current attainment given current patterns of energy consumption in rural China, which rely so heavily on unprocessed solid fuels. Even when used with chimneys, these fuels emit substantial pollution into the household environment. It is probable that low-emission technologies involving gaseous/liquid fuels or high combustion - efficiency biomass stoves need to be promoted in order to achieve these standards for the greater part of the population.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monóxido de Carbono/análise , Culinária , Material Particulado/análise , Poluentes Atmosféricos/normas , Biomassa , Testes Respiratórios , Monóxido de Carbono/metabolismo , Monóxido de Carbono/normas , China , Carvão Mineral , Monitoramento Ambiental/normas , Feminino , Utensílios Domésticos , Habitação , Humanos , Masculino , Tamanho da Partícula , Material Particulado/normas , Petróleo , Medição de Risco , Estações do Ano , Madeira
4.
Indoor Air ; 17(2): 135-42, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17391236

RESUMO

UNLABELLED: Diverse indoor combustion sources contribute to the indoor air environment. To evaluate the effect of these sources on human respiratory health, we examined associations between respiratory conditions and household factors in the 2360 children's fathers (mean = 38.4 years old) and associations between lung function and household factors in 463 primary school children (mean = 8.3 years old) from Wuhan, China. Factor analysis developed new uncorrelated 'factor' variables. Unconditional logistic regression models or linear regression models, controlling for important covariates, estimated the respiratory health effects. Coal smoke derived from home heating ('heating coal smoke') was associated with high adult reporting of persistent cough, persistent phlegm, and wheeze. Cooking coal smoke was associated with physician-diagnosed adult asthma and decreased forced vital capacity (FVC), and forced expiratory volume at 1 s (FEV(1)) in children. The presence of any home cigarette smoker was associated with more reports of persistent cough, persistent phlegm, cough with phlegm, and bronchitis. Our study suggests that in Wuhan, there may be independent respiratory health effects of different indoor combustion sources and their exposure factors for these study populations. PRACTICAL IMPLICATIONS: We conclude that multiple indoor air pollution sources could have adverse respiratory health effects on both children and middle-aged men in the city of Wuhan, China. These results may have implications for the Wuhan local government, the Chinese government, or other related organizations in efforts on protecting public health through regulation of indoor air pollution from indoor combustion sources.


Assuntos
Poluentes Atmosféricos/toxicidade , Poluição do Ar em Ambientes Fechados/efeitos adversos , Carvão Mineral/toxicidade , Culinária , Pneumopatias/etiologia , Adulto , Criança , China/epidemiologia , Análise Fatorial , Pai , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Calefação , Habitação , Humanos , Exposição por Inalação/efeitos adversos , Pneumopatias/epidemiologia , Masculino , Inquéritos e Questionários , Poluição por Fumaça de Tabaco , Capacidade Vital/efeitos dos fármacos
5.
J Radiol Prot ; 26(3): 277-86, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16926470

RESUMO

With the increasing number of multi-terawatt (10(12) W) and petawatt (10(15) W) laser interaction facilities being built, the need for a detailed understanding of the potential radiological hazards is required and their impact on personnel is of major concern. Experiments at a number of facilities are being undertaken to achieve this aim. This paper describes the recent work completed on the Vulcan petawatt laser system at the CCLRC Rutherford Appleton Laboratory, where photon doses of up to 43 mSv at 1 m per shot have been measured during commissioning studies. It also overviews the shielding in place on the facility in order to comply with the Ionising Radiation Regulations 1999 (IRR99), maintaining a dose to personnel of less than 1 mSv yr(-1) and as low as reasonably practicable (ALARP).


Assuntos
Lasers/efeitos adversos , Exposição Ocupacional , Fótons , Humanos , Doses de Radiação , Proteção Radiológica , Radiometria
6.
Phys Rev Lett ; 90(17): 175001, 2003 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-12786076

RESUMO

Measurements of energetic electron beams generated from ultrahigh intensity laser interactions (I>10(19) W/cm(2)) with dense plasmas are discussed. These interactions have been shown to produce very directional beams, although with a broad energy spectrum. In the regime where the beam density approaches the density of the background plasma, we show that these beams are unstable to filamentation and "hosing" instabilities. Particle-in-cell simulations also indicate the development of such instabilities. This is a regime of particular interest for inertial confinement fusion applications of these beams (i.e., "fast ignition").

7.
Appl Occup Environ Hyg ; 16(8): 791-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11504356

RESUMO

The adhesion of house dust particles and chemical residues to the hands after contact with a variety of surfaces can yield significant exposures to children. Chemicals present on the surface or absorbed into house dust particles may adhere to the hands and subsequently are available for ingestion or absorption through the skin under normal physiological conditions. Contact of a hand with a surface occurs primarily through a thin layer of sebum and sweat on the skin surface. The study presented here examined the effect of the composition of the sebum and sweat layer on the adhesion of a mixture of pesticides and a herbicide to a hand after contact with a house-dust-laden surface. Collection efficiencies on the hand for atrazine and malathion were correlated with sebum levels on the palm of an individual hand. The increase in sebum values measured in this study caused a 13 percent and 8 percent reduction in collection efficiency, respectively, for atrazine and malathion applied to house-dust-laden surfaces. Diazinon and chlorpyrifos collection efficiencies were correlated with skin hydration levels measured on the palm of the individual's hand. The increased skin hydration measured in this study caused a 7 percent and 5 percent reduction in collection efficiency, respectively, for diazinon and chlorpyrifos.


Assuntos
Herbicidas/farmacocinética , Praguicidas/farmacocinética , Equilíbrio Hidroeletrolítico , Criança , Exposição Ambiental , Mãos , Herbicidas/análise , Humanos , Praguicidas/análise , Sebo/química , Pele/química , Manejo de Espécimes , Suor/química
8.
Scott Med J ; 46(2): 52-3, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11394340

RESUMO

A case of congenital renal arteriovenous malformation (AVM), presenting with profuse haematuria in the second trimester of pregnancy is reported. Selective embolisation with polyvinyl alcohol particles and absolute alcohol successfully ablated the lesion and a healthy infant was delivered at term five months later. Renal angiography at three years showed no evidence of the lesion.


Assuntos
Malformações Arteriovenosas/terapia , Oclusão com Balão , Nefropatias/terapia , Complicações na Gravidez/terapia , Adulto , Feminino , Humanos , Gravidez
9.
J Endovasc Ther ; 8(2): 135-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11357972

RESUMO

PURPOSE: To describe a technique for common iliac artery (CIA) access during endovascular aortic aneurysm repair when unfavorable angulation between the CIA and the delivery sheath precludes direct arterial access. TECHNIQUE: After retroperitoneal exposure of the CIA, a puncture site is chosen inferolateral to the surgical incision, and an 18-G trocar/cannula is advanced in alignment with the CIA through the anterior abdominal wall or skin of the upper thigh into the retroperitoneal space. Serial dilatation is performed over a guidewire placed through the cannula to create the subcutaneous tract. The trocar/cannula is replaced over the wire, and the CIA is punctured under direct vision. The guidewire is then advanced into the proximal aorta. A CIA arteriotomy is performed and the delivery system introduced over the guidewire through the tunnel into the iliac artery. CONCLUSIONS: Retroperitoneal exposure of the CIA with tunneled transabdominal wall delivery of the stent-graft avoids both external iliac artery injury and creation of a temporary access conduit in patients with iliac tortuosity and/or occlusive disease.


Assuntos
Músculos Abdominais/cirurgia , Aorta Torácica/cirurgia , Artéria Ilíaca/cirurgia , Procedimentos Cirúrgicos Vasculares/instrumentação , Humanos
10.
J Vasc Interv Radiol ; 12(3): 337-41, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11287511

RESUMO

PURPOSE: To assess the feasibility of embolization of aortic side branches and its impact on the incidence of type II endoleak after endovascular aneurysm repair. MATERIALS AND METHODS: Endovascular aneurysm repair was performed in 74 patients. Aortic side branch vessels were evaluated on the preoperative angiogram and computed tomography (CT) and, where embolization of lumbar and inferior mesenteric vessels was considered technically possible, this was attempted prior to endovascular repair. Follow-up CT was used to assess the presence of type II endoleak. RESULTS: Seventy-two patients were followed up for longer than 1 month. Embolization was attempted in 25 cases, successfully in 10, with partial success in 11, and failure in four. Twenty patients with successful or partly successful preoperative embolization were discharged and followed-up. Four (20%) had demonstrable type II endoleak during follow-up, with two of these persisting at latest follow-up. Of 43 patients without previous embolization, there were 10 (23.3%) type II endoleaks during the follow-up period, four of these persisting. In cases with type II endoleak, mean sac diameter change was -0.5 mm in the cases with previous embolization and +3.1 mm without. The mean period to onset of type II endoleak was 6.9 months without, and 15.3 months with, previous embolization. CONCLUSION: Although the cohort size is below a level that would confer significance, the trend of these findings is such as to suggest a lack of influence of aortic side branch embolization on the incidence of type II endoleak during the follow-up period.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Oclusão com Balão , Embolização Terapêutica , Complicações Pós-Operatórias/prevenção & controle , Angiografia , Aorta Abdominal/diagnóstico por imagem , Estudos de Viabilidade , Seguimentos , Humanos , Incidência , Complicações Pós-Operatórias/epidemiologia , Cuidados Pré-Operatórios , Fatores de Tempo , Tomografia Computadorizada por Raios X
11.
J Expo Anal Environ Epidemiol ; 11(6): 501-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11791166

RESUMO

The National Human Exposure Assessment Survey (NHEXAS)/Minnesota Children's Pesticide Exposure Study (MNCPES) was a population-based study designed to characterize children's exposure to residential pesticides and to evaluate the contribution of residential and children's activities to children's exposure. Families of 168 children were surveyed for residential use of pesticides and children's activities. From these homes, families of 102 children between the ages of 3 and 13 years participated in a week-long intensive exposure study. Of the 102 children, 19 children were videotaped for four consecutive hours in their normal daily activities. The survey responses indicated that the youngest children were more likely to exhibit behaviors that would foster exposure to environmental contaminants. Comparison of questionnaire responses indicated that the videotaped subsample was representative of the exposure study population. The microactivities of the videotaped children that might contribute to their exposure via ingestion or dermal routes were quantified. Hand-to-mouth and object-to-mouth activities were observed most frequently among the youngest children. The youngest children were also most likely to be barefoot both indoors and outside. Gender differences were found in mouthing behavior and the proportion of observed time spent outdoors.


Assuntos
Atividades Cotidianas , Comportamento Infantil , Proteção da Criança , Exposição Ambiental , Praguicidas/análise , Administração Cutânea , Administração Oral , Adolescente , Criança , Pré-Escolar , Meio Ambiente , Feminino , Mãos , Inquéritos Epidemiológicos , Habitação , Humanos , Masculino , Boca , Fatores Sexuais , Gravação em Vídeo
12.
Cardiovasc Intervent Radiol ; 23(5): 358-63, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11060365

RESUMO

PURPOSE: To investigate the incidence, significance, and mechanism of stent-graft distortion after endovascular repair (EVR) of abdominal aortic aneurysm. METHODS: EVR of abdominal aortic aneurysm was performed in 51 cases (49 modular, bifurcated; 2 tube). Thirty-two patients were followed for 6 or more months and had equivalent baseline and follow-up images which could be used to determine changes in graft configuration. Sac dimensions were measured using computed tomographic (CT) images and graft-related complications were recorded. RESULTS: Amongst 32 patients evaluated on follow-up, there was graft distortion in 24. Distorted grafts were significantly (p = 0.002) associated with sac diameter reduction (mean 5 mm) and sac length reduction (mean 8.1 mm). All graft-related complications occurred in the limbs of eight distorted grafts, with a mean reduction of sac length in this group of 7.8 mm on reformatted CT images. CONCLUSION: There was a highly significant association between graft distortion and limb complications, and reduced sac dimensions.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular , Complicações Pós-Operatórias/etiologia , Idoso , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aortografia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Modelos Estatísticos , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/epidemiologia , Stents , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Grau de Desobstrução Vascular
14.
J Expo Anal Environ Epidemiol ; 10(4): 327-40, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10981727

RESUMO

During the Minnesota Children's Pesticide Exposure Study (MNCPES), comparisons were made between the insecticide/herbicide loadings obtained with two household dust/insecticide or herbicide samplers: the Edwards and Lioy (EL) press sampler (used for dust collection from carpets or other surfaces) and the Lioy, Waimnan and Weisel (LWW) surface wipe sampler. The results were compared with hand rinse levels, and urine metabolite levels obtained from 102 children (ages 3-13). All measurements were made during a 1-week sampling period, and information was obtained on household pesticide use and each child's activities. Of the homes, <5% had recent spot uses of a pesticide but none had recent general applications. The analyses focused primarily on atrazine (a herbicide), and malathion, diazinon, and chlorpyrifos (insecticides). Metabolites were measured for atrazine, malathion and chlorpyrifos. The atrazine levels obtained using the EL indicate that this compound was transported into the home by an unquantified transport mechanism (e.g. tracking of soil). Two malathion hand rinse values exceeded >170 ng/cm2, suggesting that since indoor surface levels were low, these children had other sources of exposure. Atrazine, chlorpyrifos and malathion were detectable in >30% of the homes by the EL, LWW or hand rinse. Only chlorpyrifos had detectable levels in > or = 50% of the samples for all types, i.e. compound or metabolite, which is consistent with it being a common household pesticide. The median (and maximum) chlorpyrifos levels for the EL surface, EL carpet, LWW surface (two rooms), hand rinse, and urine metabolites were: 0.07 (32.6) ng/cm2; 0.07 (44.5) ng/cm2; 0.34 (3.64) ng/cm2; 0.42 (14.4) ng/cm2; 0.03 (2.14) ng/hand and 6.9 (59.0) microg/g, respectively. A strong correlation was found for chlorpyrifos between the EL surface and carpet samples. Chlorpyrifos levels detected by LWW had a different distribution and concentration range than the EL, indicating that it collected more than the surface dislodgeable insecticide. EL was directly comparable to the hand rinse or urine levels, but only the LWW had a weak correlation with hand rinse levels, suggesting that the children had other sources of chlorpyrifos exposure. Thus, mechanistic exposure studies are needed to more accurately establish exposure dose relationships in residential settings.


Assuntos
Exposição Ambiental/análise , Herbicidas/análise , Inseticidas/análise , Adolescente , Criança , Comportamento Infantil , Pré-Escolar , Poeira , Monitoramento Ambiental/métodos , Feminino , Desinfecção das Mãos , Habitação , Humanos , Masculino , Manejo de Espécimes/métodos
15.
J Vasc Interv Radiol ; 11(7): 891-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10928528

RESUMO

PURPOSE: To demonstrate that proximal esophageal stenoses and tracheoesophageal fistulas can be adequately palliated with use of metallic stents without significant foreign-body sensation. MATERIALS AND METHODS: Between June 1994 and March 1999, 22 patients with lesions within 3 cm of the cricopharyngeus were treated by placement of metallic stents. The series was reviewed retrospectively. Twenty patients had surgically unresectable malignant lesions, two patients had benign disease. Ten patients had associated tracheoesophageal fistulas. In all, the upper limit of the stent was between C5 vertebral body inferior endplate and the T2 vertebral body superior endplate. The case-notes were reviewed until patient death (range, 6-198 days), or to date in the two surviving patients with benign disease. RESULTS: Immediate technical success was 93% (27 of 29). Dysphagia scores improved from a median of 3 to 2 after stent placement. Eighteen of 22 (82%) patients reported no foreign-body sensation. There have been no cases of proximal migration, periprocedural perforation, or deaths. The two patients with benign disease experienced significant complications. CONCLUSION: Lesions in proximity to the cricopharyngeus can be successfully palliated without significant foreign-body sensation in the majority of patients with use of metallic stents. The authors urge caution in placing stents in patients with benign disease.


Assuntos
Estenose Esofágica/terapia , Esôfago , Metais , Stents , Fístula Traqueoesofágica/terapia , Adulto , Idoso , Deglutição/fisiologia , Transtornos de Deglutição/terapia , Neoplasias Esofágicas/complicações , Estenose Esofágica/etiologia , Esôfago/lesões , Esôfago/efeitos da radiação , Feminino , Seguimentos , Corpos Estranhos/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Satisfação do Paciente , Lesões por Radiação/complicações , Recidiva , Estudos Retrospectivos , Sensação/fisiologia , Estatísticas não Paramétricas , Stents/efeitos adversos , Taxa de Sobrevida , Resultado do Tratamento
16.
J Vasc Interv Radiol ; 11(2 Pt 1): 225-31, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10716395

RESUMO

PURPOSE: To compare the technical success and immediate and long-term outcomes of tunneled central venous catheters placed in comparative cohorts via the subclavian vein (SCV) and the internal jugular vein (IJV) routes. MATERIALS AND METHODS: This was a prospective observational single-center study of consecutive procedures. Between November 1993 and June 1995, 99 catheters were placed via the SCV and between December 1997 and July 1998, 109 catheters were placed via the IJV. Procedural data were recorded in both cohorts by completion of a proforma by the primary operator. RESULTS: Follow-up data were available in 96% of the SCV and 87% of the IJV cohorts. The average procedure time was significantly shorter in the IJV group and technical success was 100% versus 97% in the SCV group, but this did not reach statistical significance. The procedure-related pneumothorax rate and the rate of symptomatic venous thrombosis were significantly lower in the IJV cohort (P = .023, P = .015). Fewer catheters were removed prematurely due to sepsis in the IJV group (P = .043). CONCLUSIONS: The IJV route is associated with comparable technical success, and lower major procedural complication and venous thrombosis rates, with fewer catheters removed prematurely. The right IJV approach with ultrasound guidance is recommended as the route of choice for the placement of tunneled central venous catheters.


Assuntos
Cateterismo Venoso Central , Veias Jugulares , Veia Subclávia , Cateterismo Venoso Central/instrumentação , Cateterismo Venoso Central/métodos , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo
17.
J Expo Anal Environ Epidemiol ; 9(5): 521-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10554154

RESUMO

Indirect sampling techniques to estimate dermal exposure to pesticides on housedust-laden indoor surfaces should demonstrate collection efficiencies, for both particles and pesticide residues, which are similar to those that would adhere to the human skin. A spring-loaded press sampler has been developed that approximated the particle- and pesticide-collection efficiencies of a hand press of a human participant. Particle-collection efficiencies for the hand press and EL sampler, using housedust sieved to <250 microm in diameter, indicated that both sampling techniques collected similar particle fractions over the range of particle sizes. Pesticide-collection efficiencies measured on the participants hand (seven paired tests) were 42+/-7% atrazine, 29+/-8% diazinon, 43+/-8% malathion and 21+/-5% chlorpyrifos. The EL sampler collected 35+/-5%, 31+/-3%, 32+/-5% and 18+/-3% respectively. The collection efficiencies of the two sampling techniques were highly correlated for atrazine, diazinon, and chlorpyrifos (correlation coefficient=0.840, 0.815, and 0.706), but not for malathion (correlation coefficient=0.086).


Assuntos
Poeira/análise , Monitoramento Ambiental/instrumentação , Resíduos de Praguicidas/análise , Monitoramento Ambiental/métodos , Desenho de Equipamento , Feminino , Filtração , Mãos , Humanos , Masculino , Tamanho da Partícula , Controle de Qualidade , Valores de Referência , Absorção Cutânea
18.
Sci Total Environ ; 224(1-3): 69-80, 1998 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-9926426

RESUMO

Seasonal differences in the particle size fractions and mass loadings of household dust deposited on indoor surfaces were examined in four New Jersey homes. Housedust was collected during a 30-day period on non-electrostatic polyethylene sample plates on which a glass slide had been placed. In each home two samples were collected at a height of 1.5 m and two were collected at a height of 0.3 m above the floor. Dust samples were obtained from each home during a summer and winter collection period. Particle size measurement was completed using an adaptation of a Meridian ACAS 570 Interactive Laser Cytometer. Results indicated that the dust mass deposited on household surfaces during the summer was greater than during the winter. The arithmetic mean mass deposition rate for all houses was 0.37 +/- 0.13 microgram/cm2/day during the summer and 0.22 +/- 0.13 microgram/cm2/day during the winter. The total number of particles deposited, however, was greater during the winter than during the summer. The increase in winter time particle number was caused by greater numbers of particles with an equivalent spherical diameter < 2.5 microns. The most probable source of these particles was winter time combustion emissions within the residences and the subsequent particle deposition on household surfaces. The greater mass loadings measured on the low sampling plates during the summer were associated with a greater number of particles with an equivalent spherical diameter > 5 microns. In the winter, however, the particle mass and number loadings were similar at both heights. These results suggested that ventilation of the house during the summer allowed resuspended particles to enter which led to the higher levels of settled dust. Measurement of contaminant levels in housedust for exposure estimation therefore, should account for the seasonal and height differences in dust mass, and collect representative fractions of housedust that are available for human contact. Furthermore, since over 99% of the particles on indoor surfaces were < 50 microns any indirect sampling technique for dermal exposure estimation should have collection efficiencies similar to the hand of particles < 50 microns.


Assuntos
Poeira/análise , Habitação , Estações do Ano , Citometria de Fluxo/métodos , Humanos , New Jersey , Tamanho da Partícula
19.
Clin Radiol ; 52(6): 451-7, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9202589

RESUMO

We report the technical and early clinical results of renal artery stent placement in 29 consecutive patients treated at a single centre over a 30-month period, employing the Palmaz balloon-expandable stent. Of 32 arteries treated, 23 (72%) were atheromatous, ostial stenoses. Immediate technical success was achieved in all 29 patients. Follow-up angiography was performed on 25 patients at 6.7 months (mean) and demonstrated a patient restenosis rate of 16%. All surviving patients were followed up for a minimum of 6 months. Blood pressure control was improved in eight (50%) of hypertensive patients, and renal function improved in seven (33%) and stabilized in six (29%) patients with chronic renal impairment (serum creatinine > 150 mumols/l). Complications occurred in seven (24%) of patients, including one procedure-related death. Our experience indicates that stent placement has an initial high technical success rate in renal artery stenosis and that this patency is maintained at repeat angiography with a low restenosis rate. Renal artery stenting is likely to extend the role of percutaneous renal revascularization especially in atheromatous ostial lesions. A randomized trial will be required to evaluate its role compared with balloon angioplasty.


Assuntos
Angioplastia com Balão , Obstrução da Artéria Renal/terapia , Stents , Adulto , Idoso , Pressão Sanguínea , Feminino , Seguimentos , Humanos , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Radiografia , Recidiva , Obstrução da Artéria Renal/diagnóstico por imagem , Obstrução da Artéria Renal/fisiopatologia , Stents/efeitos adversos , Taxa de Sobrevida , Grau de Desobstrução Vascular
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