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1.
Environ Res ; 231(Pt 1): 115908, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37149026

RESUMO

Corona ions produced by high voltage power lines (HVPL) can alter the local atmospheric electrical environment downwind, potentially increasing electrostatic charge on airborne particulates via ion-aerosol attachment. However, previous epidemiological assessments attempting to assess this 'corona ion hypothesis' have used proxies e.g. ion concentration or distance from HVPL, rather than aerosol charge state directly, due to difficulties in modeling this quantity. We present a quasi-1D model incorporating both Gaussian plume dynamics and ion-aerosol and ion-ion interaction microphysics which could be applied to future studies of charged aerosol near HVPL. The response of the model to changes in a range of input parameters is characterized, and validation is attempted by means of comparison with previous work where ion- and aerosol concentrations and properties (including electrical mobility and electric charge states) upwind and downwind of HVPL are measured.


Assuntos
Poeira , Eletricidade , Aerossóis , Íons
2.
Environ Res ; 228: 115834, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37037314

RESUMO

Corona ions from high voltage power lines (HVPL) can increase electrostatic charge on airborne pollutant particulates, possibly increasing received dose upon inhalation. To investigate the potential increased risk of childhood leukemia associated with residence near alternating current (AC) HVPL, we measured the particle charge state and atmospheric electricity parameters upwind, downwind and away from HVPL. Although we observed noticeable charge state alteration from background levels, most HVPL do not significantly increase charge magnitude. Particular HVPL types are shown to have most effect, increasing net charge to 15 times that at background. However, the magnitude of charge alteration during rainfall is comparable with the most extreme HVPL measurement. On current evidence, based on the current adult lung model, we suggest that although charge is sometimes enhanced to levels which may alter atmospheric particle dynamics, increased lung deposition is unlikely.


Assuntos
Poluentes Atmosféricos , Pulmão , Pulmão/química , Eletricidade , Aerossóis , Poluentes Atmosféricos/análise , Chuva , Tamanho da Partícula
3.
Artigo em Inglês | MEDLINE | ID: mdl-37047932

RESUMO

Traffic is a major source of particulate pollution in large cities, and particulate matter (PM) level in Bangkok often exceeds the World Health Organisation limits. While PM2.5 and PM10 are both measured in Bangkok regularly, the sub-micron range of PM, of specific interest in regard to possible adverse health effects, is very limited. In the study, particle number concentration (PNC) was measured on public transport in Bangkok. A travel route through Bangkok using the state railway, the mass rapid transport underground system, the Bangkok Mass Transit System (BTS) Skytrain and public buses on the road network, with walking routes between, was taken whilst measuring particle levels with a hand-held concentration particle counter. The route was repeated 19 times covering different seasons during either morning or evening rush hours. The highest particle concentrations were found on the state railway, followed by the bus, the BTS Skytrain and the MRT underground with measured peaks of 350,000, 330,000, 33,000 and 9000 cm-3, respectively, though particle numbers over 100,000 cm-3 may be an underestimation due to undercounting in the instrument. Inside each form of public transport, particle numbers would peak when stopping to collect passengers (doors opening) and decay with a half-life between 2 and 3 min. There was a weak correlation between particle concentration on bus, train and BTS and Skytrain with carbon monoxide concentration, as measured at a fixed location in the city.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Tailândia , Material Particulado/análise , Meios de Transporte , Exposição Ambiental/análise , Monitoramento Ambiental , Poluição do Ar/análise , Tamanho da Partícula , Emissões de Veículos/análise
4.
Sci Med Footb ; 7(1): 81-92, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35068376

RESUMO

Players involved in the various football codes compete throughout the calendar year around the world. Therefore, environmental stressors such as temperature and altitude should be considered in preparation for, and during, matches. We aimed to systematically review the observational and quasi-experimental studies that have been specifically designed to quantify the effects of temperature (hot or cold) high altitude on in-match physical performance indicators. A search of electronic databases (Web of Science, Scopus, SPORTDiscus, PubMed/MEDLINE) was conducted, with 19,424 papers identified as relevant. Following sifting in relation to the eligibility criteria, 12 papers were deemed directly relevant. The reviewed studies scored 6-9 (on a 0-9 scale) for quality assessment using a previously used scale. The major outcome variables relevant to the current review were total distance (m), high-speed running (m) and high-speed runs (count) measured during matches. Standardized effect sizes (ES) were heterogeneous across studies for total distance (ES: -0.96 to -0.14) and high-speed running (ES: -0.69 to 0.12) for >1000 m vs sea-level, time spent at the given altitude being a putative factor for this heterogeneity. Heat had mainly detrimental effects on performance, but ES were, again, heterogeneous across studies (ES: -1.25 to 0.26), dependent on temperature. Given the small number of studies that involved mostly male athletes, and large heterogeneity across studies, more research needs be conducted on physical performance in these environmental conditions, with attention paid to standardizing outcomes and broadening the approaches of studies to guide future decision-making in professional sporting environments.


Assuntos
Desempenho Atlético , Futebol Americano , Humanos , Masculino , Feminino , Temperatura , Altitude , Atletas
5.
J Natl Cancer Inst ; 114(11): 1511-1522, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36239760

RESUMO

BACKGROUND: There is increasing interest in better understanding the biology and clinical presentation of invasive lobular cancer (ILC), which is the most common special histological subtype of breast cancer. Limited large contemporary data sets are available allowing comparison of clinicopathologic features between ILC and invasive ductal cancer (IDC). METHODS: The Great Lakes Breast Cancer Consortium was formed to compare clinical behavior of ILC (n = 3617) and IDC (n = 30 045) from 33 662 patients treated between 1990 and 2017 at 3 large clinical centers. We used Kaplan-Meier analysis, Cox proportional hazards modeling, and propensity score matching to evaluate treatment differences and outcomes. All statistical testing used 2-sided P values. RESULTS: Compared with IDC, patients with ILC were more frequently diagnosed at later stages and with more lymph node involvement (corrected P < .001). Estrogen receptor-positive ILCs were of lower grade (grade 1 and 2: 90% in ILC vs 72% in IDC) but larger in size (T3 and 4: 14.3% in ILC vs 3.4% in IDC) (corrected P < .001), and since 1990, the mean ILC size detected at diagnosis increased yearly. Patients with estrogen receptor (ER)-positive ILC underwent statistically significantly more mastectomies compared with ER-positive IDC (57% vs 46%). Using Kaplan-Meier analysis, patients with ER-positive ILC had statistically significantly worse disease-free survival and overall survival than ER-positive IDC although 6 times more IDCs were classified as high risk by OncotypeDx Breast Recurrence Score assay. CONCLUSIONS: This large, retrospective, collaborative analysis with 3 clinical centers identified meaningful differences in clinicopathological features between ILC and IDC, providing further evidence that these are 2 different entities requiring different clinical management.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Lobular , Humanos , Feminino , Carcinoma Ductal de Mama/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Receptores de Estrogênio , Estudos Retrospectivos , Carcinoma Lobular/diagnóstico
6.
Environ Sci Pollut Res Int ; 29(52): 79025-79040, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35705762

RESUMO

Inhalable particulate matter (PM) is a health concern, and people living in large cities such as Bangkok are exposed to high concentrations. This exposure has been linked to respiratory and cardiac diseases and cancers of the lung and brain. Throughout 2018, PM was measured in northern Bangkok near a toll road (13.87°N, 100.58°E) covering all three seasons (cool, hot and rainy). PM10 was measured in 24- and 72-h samples. On selected dates aerodynamic size and mass distribution were measured as 3-day samples from a fixed 5th floor inlet. Particle number concentration was measured from the 5th floor inlet and in roadside survey measurements. There was a large fraction of particle number concentration in the sub-micron range, which showed the greatest variability compared with larger fractions. Metals associated with combustion sources were most found on the smaller size fraction of particles, which may have implications for associated adverse health outcomes because of the likely location of aerosol deposition in the distal airways of the lung. PM10 samples varied between 30 and 100 µg m-3, with highest concentrations in the cool season. The largest metal fractions present in the PM10 measurements were calcium, iron and magnesium during the hot season with average airborne concentrations of 13.2, 3.6 and 2.0 µg m-3, respectively. Copper, zinc, arsenic, selenium, molybdenum, cadmium, antimony and lead had large non-crustal sources. Principal component analysis (PCA) identified likely sources of the metals as crustal minerals, tailpipe exhaust and non-combustion traffic. A health risk analysis showed a higher risk of both carcinogenic and non-carcinogenic health effects in the drier seasons than the wet season due to ingestion of nickel, arsenic, cadmium and lead.


Assuntos
Poluentes Atmosféricos , Arsênio , Selênio , Humanos , Poluentes Atmosféricos/análise , Cádmio/análise , Níquel/análise , Arsênio/análise , Antimônio/análise , Cobre/análise , Magnésio/análise , Selênio/análise , Molibdênio/análise , Cálcio/análise , Tailândia , Monitoramento Ambiental , Material Particulado/análise , Aerossóis/análise , Zinco/análise , Ferro/análise , Tamanho da Partícula
7.
PLoS One ; 17(2): e0261812, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35108298

RESUMO

Using Brofenbrenner's socio-ecological model as a conceptual framework, the objective of this study was to determine playground users (primary school staff and pupils) perceptions of the barriers and facilitators to a physically active school playground at an intra-personal (individual), inter-personal (social), environmental and policy level. Results from a series of qualitative interactions with children (n = 65) from years five and six (9 to 11 years old), and structured interviews with adult teachers (n = 11) revealed key differences in the child and adult perceptions of the playground and the purpose of break-times. A number of inter-related environmental boundaries and school policies were identified as restrictive to children's explorations and activity levels during 'free play' periods, which centred on resource availability, accessibility and health and safety. Further, traditional playground hierarchies act to promote and prevent physical activity engagement for different groups (e.g. gender and age). Finally, differences between the adult and child perception of the primary school playground were observed. Playground physical activity, during break-times appears to be affected by a number of variables at each level of the socio-ecological model. This study provides an opportunity for primary schools to reflect on primary school playground strategies and practices that are implemented at each level of the socio-ecological model to encourage a more effective use of the playground during school break-times.


Assuntos
Jogos e Brinquedos , Professores Escolares/psicologia , Estudantes/psicologia , Criança , Exercício Físico , Feminino , Grupos Focais , Humanos , Entrevistas como Assunto , Masculino , Instituições Acadêmicas
8.
Ann Surg Oncol ; 28(10): 5723-5729, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34324111

RESUMO

BACKGROUND: Invasive lobular carcinoma (ILC) is thought be a unique entity with higher rates of multifocal/multicentric and bilateral disease. This study aimed to evaluate the true extent of the disease, risk of bilaterality, lymph node involvement, and impact of preoperative imaging to help guide surgical decision making. METHODS: A retrospective analysis identified patients treated for ILC between 2004 and 2017. Clinical staging and pathologic results were compared. Follow-up details including local recurrence, contralateral breast cancer (CBC), and survival outcomes were evaluated. RESULTS: The study identified 692 patients with ILC, including 43 patients (6%) with a diagnosis of CBC and 232 patients (33%) with a diagnosis of multifocal/multicentric disease at presentation. Preoperative magnetic resonance imaging (MRI) led to an identification of additional disease in 20% of the patients. Preoperative MRI resulted in a more accurate prediction of tumor size staging but did not improve the discordance between clinical and pathologic nodal staging. Overall, the rate of imaging occult lymph node disease was 24%. At the 6-year follow-up evaluation, a local recurrence had developed in 2.3%, a CBC in 2.3, and a distant metastasis in 9.4% of the patients. The overall survival rate was 96% at 3 years and 91% at 5 years. CONCLUSIONS: Invasive lobular carcinoma is a distinct subset of cancer that poses a diagnostic staging challenge. The results of this study favor MRI for accurate tumor staging and for improving detection of multicentricity and bilaterality. However, clinicians should be aware of the higher likelihood of occult lymph node involvement with ILC and subsequent early metastasis.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Lobular , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/patologia , Carcinoma Lobular/cirurgia , Tomada de Decisões , Feminino , Humanos , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Estudos Retrospectivos
9.
Expert Opin Drug Discov ; 16(5): 485-496, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33280445

RESUMO

Introduction: Cyclin-dependent kinase (CDK) 4/6 inhibitors have altered the standard-of-care treatment for patients with ER-positive, HER2-negative metastatic breast cancer. One such inhibitor, abemaciclib, a reversible ATP-competitive CDK4/6 inhibitor developed by Eli Lilly and Company, was approved by the FDA for ER-positive, HER2-negative metastatic breast cancer.Areas covered: Preclinical studies revealed abemaciclib's distinct structure, efficacy as monotherapy, and ability to penetrate the Central Nervous System. In this review, the authors have examined the literature regarding the development of CDK 4/6 inhibitors before providing a focused review on the preclinical discovery and development of abemaciclib. The authors then conclude their manuscript by providing their expert opinion and future perspectives.Expert opinion: Understanding the genesis and evolution from concept to approval and beyond will allow one to analyze the impact of abemaciclib. With its unique characteristics, abemaciclib has provided a meaningful addition to the therapeutic arsenal for metastatic breast cancer. There is, however, a need for predictive biomarkers to identify patients who may not benefit from or may develop resistance to CDK4/6 inhibition.


Assuntos
Aminopiridinas/administração & dosagem , Antineoplásicos/administração & dosagem , Benzimidazóis/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Aminopiridinas/farmacologia , Animais , Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Neoplasias da Mama/patologia , Desenvolvimento de Medicamentos , Descoberta de Drogas , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia
10.
Int J Sports Physiol Perform ; 15(9): 1315-1323, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32947260

RESUMO

PURPOSE: To understand the validity of differential ratings of perceived exertion (dRPE) as a measure of girls' training and match internal loads. METHODS: Using the centiMax scale (CR100), session dRPE for breathlessness (sRPE-B) and leg muscle exertion (sRPE-L) were collected across a season of training (soccer, resistance, and fitness) and matches from 33 players (15 [1] y). Differences and associations between dRPE were examined using mixed and general linear models. The authors' minimal practical important difference was 8 arbitrary units (AU). RESULTS: Mean (AU [SD] ∼16) sRPE-B and sRPE-L were 66 and 61 for matches, 51 and 49 for soccer, 86 and 67 for fitness, and 45 and 58 for resistance, respectively. Session RPE-B was rated most likely harder than sRPE-L for fitness (19 AU; 90% confidence limits: ±7) and most likely easier for resistance (-13; ±2). Match (5; ±4) and soccer (-3; ±2) differences were likely to most likely trivial. The within-player relationships between sRPE-B and sRPE-L were very likely moderate for matches (r = .44; 90% confidence limits: ±.12) and resistance training (.38; ±.06), likely large for fitness training (.51; ±.22), and most likely large for soccer training (.56; ±.03). Shared variance ranged from 14% to 35%. CONCLUSIONS: Practically meaningful differences between dRPE following physical training sessions coupled with low shared variance in all training types and matches suggest that sRPE-B and sRPE-L represent unique sensory inputs in girls' soccer players. The data provide evidence for the face and construct validity of dRPE as a measure of internal load in this population.

11.
Inhal Toxicol ; 32(7): 282-298, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32689844

RESUMO

Carbon nanotube (CNT) in vivo inhalation studies are increasingly providing estimates of the quantity of material deposited in the lung, generally estimated using standard formulae and pulmonary deposition models. These models have typically been developed and validated using data from studies using sphere-like particles. Given the importance of particle morphology to pulmonary deposition, the appropriateness of such an approach was explored to identify any potential limitations. Aerosolized CNT particles typically form 'fiber-like' and/or 'broadly spherical' agglomerates. A review of currently used deposition models indicates that none have been directly validated against results for CNT, however, models for spherical particles have been extensively validated against a wide range of particle sizes and materials and are thus expected to provide reasonable estimates for most 'broadly spherical' CNT particles, although experimental confirmation of this would be of benefit, especially given their low density. The validation of fiber deposition models is significantly less extensive and, in general, focused on larger particles, e.g. asbestos. This raises concerns about the accuracy of deposition estimates for 'fiber-like' CNT particles and recommendations are made for future research to address this. An appreciation of the uncertainties on CNT deposition estimates is important for their interpretation and thus it is recommended that model sensitivity and uncertainty assessments be undertaken. Issues surrounding the measurement and derivation of model input data are also addressed, including instrument responses and particle density assessment options. Recommendations are also made for aerosol characterization to 'future-proof' CNT inhalation studies regarding advances in deposition modeling and toxicological understanding.


Assuntos
Pulmão/metabolismo , Modelos Biológicos , Nanotubos de Carbono , Aerossóis , Animais , Humanos
13.
Atmos Environ X ; 8: 100079, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33392499

RESUMO

Nanoparticles have been incorporated into a range of consumer spray products, providing the potential for inadvertent inhalation by users and bystanders. The levels and characteristics of nanoparticle inhalation exposures arising from the use of such products are important inputs to risk assessments and informing dose regimes for in vitro and in vivo studies investigating hazard potentials. To date, only a small number of studies have been undertaken to explore both the aerosols generated from such products and the metal nanoparticles within them. The objective of the current study was to add to the limited data in this field by investigating a range of nano-containing spray products available within the UK. Six products were selected and the nanoparticles characterised using a combination of techniques, including: inductively coupled plasma mass spectrometry (ICP-MS), dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), transmission electron microscopy energy-dispersive X-ray spectroscopy (TEM-EDX) and single particle ICP-MS (spICP-MS). The aerosol produced by these products, when sprayed within a glovebox, was characterised by scanning mobility particle sizer (SMPS) and an aerodynamic particle sizer (APS). A cascade impactor with thirteen stages (NanoMOUDI) was used with one product to generate information on the size specific nanoparticle elemental distribution within the aerosol. The results demonstrated the presence of solid nanoparticles (silver, gold or silica) in each of the products at low concentrations (<13 ppm). TEM and (sp)ICP-MS provided reliable information on nanoparticle size, shape, number and mass, while the light scattering methods were less effective due to the complex matrices of the products and their lack of chemical specificity. The aerosols varied significantly across products, with particle and mass concentrations spanning 5 orders of magnitude (10 - 106 cm-3 and 0.3-7600 µg m-3, respectively). The NanoMOUDI results clearly indicated non-uniform distribution of silver within different aerosol particle size ranges.

14.
J Strength Cond Res ; 33(3): 793-800, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28595239

RESUMO

Wright, MD and Atkinson, G. Changes in sprint-related outcomes during a period of systematic training in a girls' soccer academy. J Strength Cond Res 33(3): 793-800, 2019-The longitudinal tracking of performance indicators is lacking during the training of young female soccer players. Therefore, changes in 5-m acceleration, 20-m speed, change-of-direction (COD) speed, and repeated-sprint ability (RSA) were quantified during a 3-year period in an English Football Association Center of Excellence. Fourteen players (mean age = 12.1 years, SD = ±0.9) were recruited, and their best performance scores from preseason and in-season testing were averaged. Players were typically exposed to soccer (2 × 90 minutes per week) and strength and conditioning training (1 × 70 minutes per week) and played 20 soccer matches (50-80 minutes) during 35-week seasons. Mean (±90% confidence limits (CL)) overall improvements over the 3 years were 5.9% (1.3) (most likely large) for speed, 4.0% (1.0) (most likely large) for RSA, 8.8% (1.1) for acceleration, and 8.3% (1.4) for COD speed (both most likely very large). Improvements between years one and 2 ranged from most likely moderate to very large. Further small improvements in COD speed and 20-m speed (both likely) were observed between years 2 and 3. Individual differences in response were apparent only for COD speed, which were moderate and small between years 2 and 3. Most likely very large to near-perfect within-player correlations were observed between maturation and sprint measures. These data from a single-arm longitudinal study indicate that systematic exposure to training, which includes one dedicated strength and conditioning session each week, is associated with improvements in sprint-related physical qualities in girls.


Assuntos
Desempenho Atlético/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Aceleração , Adolescente , Criança , Feminino , Humanos , Estudos Longitudinais , Condicionamento Físico Humano/métodos
15.
Neurology ; 89(13): 1365-1372, 2017 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-28855403

RESUMO

OBJECTIVE: To describe long-term outcomes of children with early-infantile Krabbe disease who underwent hematopoietic stem cell transplantation (HSCT) in the first 7 weeks of life. METHODS: In this prospective longitudinal study, evaluations performed at baseline and follow-up included brain imaging, neurodiagnostic tests, and neurobehavioral evaluations. RESULTS: Of the 18 patients in this study (11 girls, 7 boys; mean follow-up 9.5 years, range 4-15), 5 died (3 of peritransplant complications, 1 of a surgical complication unrelated to Krabbe disease, 1 of disease progression). One of the surviving patients has normal cognitive function and 10 continue to develop cognitive skills at a slightly slower rate than normal. All surviving patients continue to gain receptive language skills, with 7 falling within the normal range. Ten patients receive speech therapy, and 2 of these patients require augmentative communication devices. Gross motor development varies widely, but 3 patients can walk independently, and 7 walk with assistive devices. Spasticity ranges from mild to severe, and 12 patients wear orthotics. Fine motor skills are generally preserved. Brain myelination and atrophy stabilized in 8 patients, improved in 4 patients, and worsened in 1 patient. Nerve conduction velocities initially improved but continue to be abnormal in most patients. CONCLUSIONS: The surviving patients function at a much higher level than untreated children or symptomatic children who underwent HSCT. These results show that early HSCT changes the natural history of this disease by improving both lifespan and functional abilities. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for children with early-infantile Krabbe disease, early HSCT improves lifespan and functional abilities.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Leucodistrofia de Células Globoides/fisiopatologia , Leucodistrofia de Células Globoides/terapia , Adolescente , Transplante de Medula Óssea , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiopatologia , Criança , Desenvolvimento Infantil , Pré-Escolar , Progressão da Doença , Feminino , Seguimentos , Humanos , Lactente , Estimativa de Kaplan-Meier , Leucodistrofia de Células Globoides/mortalidade , Leucodistrofia de Células Globoides/psicologia , Estudos Longitudinais , Masculino , Estudos Prospectivos , Resultado do Tratamento
16.
Artigo em Inglês | MEDLINE | ID: mdl-28230812

RESUMO

People spend the majority of their time indoors and therefore the quality of indoor air is worthy of investigation; indoor air quality is affected by indoor sources of pollutants and from pollutants entering buildings from outdoors. In this study, unique perfluorocarbon tracers were released in five experiments at a 100 m and ~2 km distance from a large university building in Manchester, UK and tracer was also released inside the building to measure the amount of outdoor material penetrating into buildings and the flow of material within the building itself. Air samples of the tracer were taken in several rooms within the building, and a CO2 tracer was used within the building to estimate air-exchange rates. Air-exchange rates were found to vary between 0.57 and 10.90 per hour. Indoor perfluorocarbon tracer concentrations were paired to outdoor tracer concentrations, and in-out ratios were found to vary between 0.01 and 3.6. The largest room with the lowest air-exchange rate exhibited elevated tracer concentrations for over 60 min after the release had finished, but generally had the lowest concentrations, the room with the highest ventilation rates had the highest concentration over 30 min, but the peak decayed more rapidly. Tracer concentrations indoors compared to outdoors imply that pollutants remain within buildings after they have cleared outside, which must be considered when evaluating human exposure to outdoor pollutants.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Fluorocarbonos/análise , Poluição do Ar/análise , Monitoramento Ambiental , Humanos , Ventilação
17.
J Sports Sci ; 34(19): 1808-15, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26881963

RESUMO

Little is known about the responses of girl athletes to training interventions throughout maturation. This study evaluated group and individual responses to an 8-week, mixed-methods, high-intensity interval training (HIIT) programme in girl football players. Thirty-seven players (age 13.4 ± 1.5 years) were tested for 20-m speed, repeated-sprint ability, change-of-direction speed and level 1 yo-yo intermittent recovery (YYIR). Players were subcategorised into before-, at- and after-PHV (peak height velocity) based on maturity offset. Very likely moderate (25%; ±90% confidence limits = 9.2) improvements occurred in YYIR, but data were unclear in players before-PHV with moderate individual differences in response. Decrements in repeated-sprint ability were most likely very large (6.5%; ±3.2) before-PHV, and likely moderate (1.7%; ±1.0) at-PHV. Data were unclear after-PHV. A very likely moderate (2.7%; ±1.0) decrement occurred in change-of-direction speed at-PHV while there was a very likely increase (-2.4%; ±1.3) in after-PHV players. Possibly small (-1.1%; ±1.4) improvements in 20-m speed occurred before-PHV but the effect was otherwise unclear with moderate to large individual differences. These data reflect specific responses to training interventions in girls of different biological maturity, while highlighting individual responses to HIIT interventions. This can assist practitioners in providing effective training prescription.


Assuntos
Treinamento Intervalado de Alta Intensidade/métodos , Educação Física e Treinamento/métodos , Resistência Física , Aptidão Física , Puberdade , Futebol , Adolescente , Atletas , Desempenho Atlético , Criança , Feminino , Futebol Americano , Humanos , Corrida
18.
J Strength Cond Res ; 29(1): 254-61, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25072666

RESUMO

The effectiveness of fundamental movement training interventions in adolescents is not fully understood. The Functional Movement Screen (FMS) may provide means of evaluating the effectiveness of such programs alongside traditional tests of physiological performance. Twenty-two children completed the FMS, plank, side plank, sit and reach, and multistage fitness test. Participants were pair matched by total FMS score and assigned to control or intervention. The intervention group received a weekly 4 × 30-minute training sessions with an emphasis on movement quality, whereas the control group was involved in generic multisport activity. A smallest worthwhile effect of 0.2 between-participant SDs was set a priori for all measures except total FMS score for which a change of 1 unit was chosen. When compared with the control, our intervention had a likely trivial effect for FMS score (0.2 Arbitrary Units [AU], 90% confidence limits ±1.2 AU), a very likely small beneficial effect for plank score (87 ± 55%), but a possibly small harmful effect for side plank score (-22 ± 49%). A likely trivial effect was observed for the sit and reach test (0.3 ± 15%), whereas the effect of the training intervention on predicted (Equation is included in full-text article.)was unclear (-0.3 ± 11%). Unexpectedly, generic multisport activity enhanced both side plank and sit and reach test performances in the control group. These results demonstrated that short-term interventions might affect specific isolated components of fitness but not FMS performance.


Assuntos
Movimento/fisiologia , Condicionamento Físico Humano/métodos , Educação Física e Treinamento/métodos , Adolescente , Desempenho Atlético/fisiologia , Criança , Teste de Esforço , Feminino , Humanos , Masculino , Condicionamento Físico Humano/fisiologia , Aptidão Física/fisiologia , Distribuição Aleatória
19.
J Am Chem Soc ; 127(50): 17948-53, 2005 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-16351126

RESUMO

The 13C NMR spectroscopy of armchair and zigzag single-walled carbon nanotubes has been investigated theoretically. Spectra for (4,4), (5,5), (6,6), (6,0), (9,0), and (10,0) nanotubes have been simulated based on ab initio calculations of model systems. The calculations predict a dominant band arising from the carbon atoms in the "tube" with smaller peaks at higher chemical shifts arising from the carbon atoms of the caps. The dominant band lies in the range of 128 and 138 ppm. Its position depends weakly on the length, width, and chirality of the tubes. The calculations demonstrate how structural information may be gleaned from relatively low-resolution nanotube 13C NMR spectra.

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