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1.
J Phycol ; 58(2): 251-266, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34902157

RESUMO

Rhodolith beds are pervasive marine biological systems in the subarctic North Atlantic. Limited knowledge about effects of temperature and irradiance on rhodolith growth limits the ability to anticipate the response of rhodolith beds to this ocean's chronic low, yet changing sea temperature and irradiance regimes. We carried out a 149-d laboratory experiment with Newfoundland Lithothamnion glaciale rhodoliths to test the predictions that growth (i) is inhibited at temperatures of ~0.5°C and (ii) resumes as temperature increases above 0.5°C, albeit at a higher rate under high than low irradiances. Rhodoliths were grown in experimental tanks at near-zero (~0.7°C) seawater temperatures during the first 85 d and at temperatures increasing naturally to ~6°C for the remaining 64 d. Rhodoliths in those tanks were exposed to either low (0.02 mol photons·m-2 ·d-1 ) or high (0.78 mol photons·m-2 ·d-1 ) irradiances during the entire experiment. Rhodoliths grew at a linear rate of ~281 µm·year-1 (0.77 µm·d-1 ) throughout the experiment under both irradiance treatments despite daily seawater temperature variation of up to 3°C. Near-zero temperatures of ~0.5 to 1.0°C did not inhibit rhodolith growth. Model selection showed that PAR-day (a cumulative irradiance index) was a better predictor of growth variation than Degree-day (a cumulative thermal index). Our findings extend to ~0.5°C the lower limit of the known temperature range (~1 to at least 16°C) over which growth in L. glaciale rhodoliths remains unaffected, while suggesting that the growth-irradiance relationship in low-light environments at temperatures below 6°C is less irradiance-driven than recently proposed.


Assuntos
Rodófitas , Temperatura Baixa , Rodófitas/fisiologia , Água do Mar , Temperatura
2.
J Strength Cond Res ; 29 Suppl 11: S192-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26506187

RESUMO

In 2013, the Canadian Armed Forces (CAF) implemented the Fitness for Operational Requirements of Canadian Armed Forces Employment (FORCE), a field expedient fitness test designed to predict the physical requirements of completing common military tasks. Given that attaining this minimal physical fitness standard may not represent a challenge to some personnel, a fitness incentive program was requested by the chain of command to recognize and reward fitness over and above the minimal standard. At the same time, it was determined that the CAF would benefit from a measure of general health-related fitness, in addition to this measure of operational fitness. The resulting incentive program structure is based on gender and 8 age categories. The results on the 4 elements of the FORCE evaluation were converted to a point scale from which normative scores were derived, where the median score corresponds to the bronze level, and silver, gold, and platinum correspond to a score which is 1, 2, and 3 SDs above this median, respectively. A suite of rewards including merit board point toward promotions and recognition on the uniform and material rewards was developed. A separate group rewards program was also tabled, to recognize achievements in fitness at the unit level. For general fitness, oxygen capacity was derived from FORCE evaluation results and combined with a measure of abdominal circumference. Fitness categories were determined based on relative risks of mortality and morbidity for each age and gender group. Pilot testing of this entire program was performed with 624 participants to assess participants' reactions to the enhanced test, and also to verify logistical aspects of the electronic data capture, calculation, and transfer system. The newly dubbed fitness profile program was subsequently approved by the senior leadership of the CAF and is scheduled to begin a phased implementation in June 2015.


Assuntos
Militares , Condicionamento Físico Humano/métodos , Aptidão Física/fisiologia , Avaliação da Capacidade de Trabalho , Adulto , Fatores Etários , Canadá , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Objetivos Organizacionais , Consumo de Oxigênio , Projetos Piloto , Recompensa , Fatores Sexuais , Circunferência da Cintura
3.
J Strength Cond Res ; 29 Suppl 11: S40-5, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26506197

RESUMO

Militaries from around the globe have predominantly used endurance training as their primary mode of aerobic physical conditioning, with historical emphasis placed on the long distance run. In contrast to this traditional exercise approach to training, interval training is characterized by brief, intermittent bouts of intense exercise, separated by periods of lower intensity exercise or rest for recovery. Although hardly a novel concept, research over the past decade has shed new light on the potency of interval training to elicit physiological adaptations in a time-efficient manner. This work has largely focused on the benefits of low-volume interval training, which involves a relatively small total amount of exercise, as compared with the traditional high-volume approach to training historically favored by militaries. Studies that have directly compared interval and moderate-intensity continuous training have shown similar improvements in cardiorespiratory fitness and the capacity for aerobic energy metabolism, despite large differences in total exercise and training time commitment. Interval training can also be applied in a calisthenics manner to improve cardiorespiratory fitness and strength, and this approach could easily be incorporated into a military conditioning environment. Although interval training can elicit physiological changes in men and women, the potential for sex-specific adaptations in the adaptive response to interval training warrants further investigation. Additional work is needed to clarify adaptations occurring over the longer term; however, interval training deserves consideration from a military applicability standpoint as a time-efficient training strategy to enhance soldier health and performance. There is value for military leaders in identifying strategies that reduce the time required for exercise, but nonetheless provide an effective training stimulus.


Assuntos
Militares , Condicionamento Físico Humano/métodos , Aptidão Física/fisiologia , Adaptação Fisiológica/fisiologia , Adulto , Canadá , Metabolismo Energético , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Estados Unidos
4.
Work ; 77(4): 1341-1357, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38552129

RESUMO

BACKGROUND: While effective apprehensions of non-compliant suspects are central to public safety, the minimal force needed to transition a suspect from standing to the ground, vital for apprehension success, has not been established. OBJECTIVE: To examine the technical-tactical behaviors of general duty police officers during simulated apprehensions and quantify the minimum force required to destabilize non-compliant suspects. METHODS: Task simulations conducted with 91 officers were analyzed to identify common grappling movements, strikes, control tactics, and changes in body posture. A separate assessment of 55 male officers aimed to determine the minimum force required for destabilization in five body regions (wrist, forearm, shoulder, mid-chest, and mid-back). Data are presented as mean±standard deviation. RESULTS: On average, apprehensions took 7.3±3.2 seconds. While all officers used grappling movements (100%) and the majority employed control tactics (75%), strikes were seldom used (4%). Apprehensions typically began with a two-handed pull (97%; Contact Phase), 55% then attempted an arm bar takedown, followed by a two-handed cross-body pull (68%; Transition/Control Phase), and a two-handed push to the ground (19%; Ground Phase). All officers began in the upright posture, with most shifting to squat (75%), kneel (58%), or bent (45%) postures to complete the apprehension. The minimum force required to disrupt balance differed across body regions (wrist: 54±12 kg; forearm: 49±12 kg; shoulder: 42±10 kg; mid-chest: 44±11 kg; mid-back: 30±7 kg, all P < 0.05), except between the shoulder and chest (P = 0.19). CONCLUSION: These findings provide insights that can enhance the design and accuracy of future apprehension evaluations and inform the optimization of law enforcement physical employment standards.


Assuntos
Aplicação da Lei , Polícia , Humanos , Masculino , Punho , Mãos
5.
PNAS Nexus ; 3(8): pgae260, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39108306

RESUMO

As on land, oceans exhibit high temporal and spatial temperature variation. This "ocean weather" contributes to the physiological and ecological processes that ultimately determine the patterns of species distribution and abundance, yet is often unrecognized, especially in tropical oceans. Here, we tested the paradigm of temperature stability in shallow waters (<12.5 m) across different zones of latitude. We collated hundreds of in situ, high temporal-frequency ocean temperature time series globally to produce an intuitive measure of temperature variability, ranging in scale from quarter-diurnal to annual time spans. To estimate organismal sensitivity of ectotherms (i.e. microbes, algae, and animals whose body temperatures depend upon ocean temperature), we computed the corresponding range of biological rates (such as metabolic rate or photosynthesis) for each time span, assuming an exponential relationship. We found that subtropical regions had the broadest temperature ranges at time spans equal to or shorter than a month, while temperate and tropical systems both exhibited narrow (i.e. stable) short-term temperature range estimates. However, temperature-dependent biological rates in tropical regions displayed greater ranges than in temperate systems. Hence, our results suggest that tropical ectotherms may be relatively more sensitive to short-term thermal variability. We also highlight previously unexplained macroecological patterns that may be underpinned by short-term temperature variability.

6.
Sci Total Environ ; 892: 164818, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37315600

RESUMO

Global marine conservation remains fractured by an imbalance in research efforts and policy actions, limiting progression towards sustainability. Rhodolith beds represent a prime example, as they have ecological importance on a global scale, provide a wealth of ecosystem functions and services, including biodiversity provision and potential climate change mitigation, but remain disproportionately understudied, compared to other coastal ecosystems (tropical coral reefs, kelp forests, mangroves, seagrasses). Although rhodolith beds have gained some recognition, as important and sensitive habitats at national/regional levels during the last decade, there is still a notable lack of information and, consequently, specific conservation efforts. We argue that the lack of information about these habitats, and the significant ecosystem services they provide, is hindering the development of effective conservation measures and limiting wider marine conservation success. This is becoming a pressing issue, considering the multiple severe pressures and threats these habitats are exposed to (e.g., pollution, fishing activities, climate change), which may lead to an erosion of their ecological function and ecosystem services. By synthesizing the current knowledge, we provide arguments to highlight the importance and urgency of levelling-up research efforts focused on rhodolith beds, combating rhodolith bed degradation and avoiding the loss of associated biodiversity, thus ensuring the sustainability of future conservation programs.


Assuntos
Biodiversidade , Ecossistema , Recifes de Corais , Poluição Ambiental , Florestas , Conservação dos Recursos Naturais
7.
Curr Zool ; 65(6): 685-695, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31857815

RESUMO

Marine invertebrates that move too slowly to evade unfavorable environmental change may instead exhibit phenotypic plasticity, allowing them to adjust to varying conditions. The orange-footed sea cucumber Cucumaria frondosa is a slow-moving suspension feeder that is preyed on by the purple sunstar Solaster endeca. The sea cucumber's antipredator behavior involves changing shape and detaching from the substratum, which might increase its probability of being displaced by water motion into an unsuitable environment. We hypothesized that sea cucumbers' antipredator responses would be diminished under stronger hydrodynamic forces, and that behavioral strategies would be flexible so that individuals could adjust to frequent changes in water flows. In a natural orange-footed sea cucumber habitat, individuals lived along a pronounced hydrodynamic gradient, allowing us to measure antipredator behavior under different water flow strengths. We placed purple sunstars in physical contact with sea cucumbers living at various points along the gradient to elicit antipredator responses. We then repeated this procedure in a laboratory mesocosm that generated weak and strong hydrodynamic forces similar to those observed at the field site. Subjects in the mesocosm experiment were tested in both wave conditions to determine if their antipredator behavior would change in response to sudden environmental change, as would be experienced under deteriorating sea conditions. Antipredator responses did not covary with hydrodynamic forces in the field. However, antipredator responses in the mesocosm experiment increased when individuals were transplanted from strong to weak forces and decreased when transplanted from weak to strong forces. Overall, our results indicate environmentally induced plasticity in the antipredator behavior of the orange-footed sea cucumber.

8.
Appl Physiol Nutr Metab ; 43(7): 663-668, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29378155

RESUMO

This investigation recruited 24 participants from both the Canadian Armed Forces (CAF) and civilian populations to complete 4 separate trials at "best effort" of each of the 4 components in the CAF Physical Employment Standard named the FORCE Evaluation: Fitness for Operational Requirements of CAF Employment. Analyses were performed to examine the level of variability and reliability within each component. The results demonstrate that candidates should be provided with at least 1 retest if they have recently completed at least 2 previous best effort attempts as per the protocol. In addition, the minimal detectable difference is given for each of the 4 components in seconds which identifies the threshold for subsequent action, either retest or remedial training, for those unable to meet the minimum standard. These results will educate the delivery of this employment standard, function as a method of accommodation, in addition to providing direction for physical training programs.


Assuntos
Militares , Saúde Ocupacional/normas , Aptidão Física , Adulto , Antropometria , Canadá , Emprego , Exercício Físico , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Reprodutibilidade dos Testes , Inquéritos e Questionários
9.
Environ Pollut ; 224: 255-264, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28209433

RESUMO

With their application as seed coatings, the use of neonicotinoid insecticides increased dramatically during the last decade. They are now frequently detected in aquatic ecosystems at concentrations susceptible to harm aquatic invertebrates at individual and population levels. This study intent was to document surface runoff and subsurface tile drain losses of two common neonicotinoids (thiamethoxam and clothianidin) compared to those of companion herbicides (atrazine, glyphosate, S-metolachlor and mesotrione) at the edge of a 22.5-ha field under a corn-soybean rotation. A total of 14 surface runoff and tile drain discharge events were sampled over two years. Events and annual unit mass losses were computed using flow-weighted concentrations and total surface runoff and tile drain flow volumes. Detection frequencies close to 100% in edge-of-field surface runoff and tile drain water samples were observed for thiamethoxam and clothianidin even though only thiamethoxam had been applied in the first year. In 2014, thiamethoxam median concentrations in surface runoff and tile drain samples were respectively 0.46 and 0.16 µg/L, while respective maximum concentrations of 2.20 and 0.44 µg/L were measured in surface runoff and tile drain samples during the first post-seeding storm event. For clothianidin, median concentrations in surface runoff and tile drain samples were 0.02 and 0.01, µg/L, and respective maximum concentrations were 0.07 µg/L and 0.05 µg/L. Surface runoff and tile drain discharge were key transport mechanisms with similar contributions of 53 and 47% of measured mass losses, respectively. Even if thiamethoxam was applied at a relatively low rate and had a low mass exportation value (0.3%), the relative toxicity was one to two orders of magnitude higher than those of the other chemicals applied in 2014 and 2015. Companion herbicides, except glyphosate in tile drains, exceeded their water quality guideline during one sampling campaign after application but rapidly resumed below these limits.


Assuntos
Agricultura , Monitoramento Ambiental , Glycine max/química , Herbicidas/análise , Inseticidas/análise , Nitrocompostos/análise , Poluentes do Solo/análise , Zea mays/química , Canadá , Água Doce , Água Subterrânea/química , Herbicidas/metabolismo , Inseticidas/metabolismo , Nitrocompostos/metabolismo , Propriedades de Superfície , Movimentos da Água , Poluição Química da Água , Qualidade da Água
10.
J Med Econ ; 20(1): 63-71, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27603674

RESUMO

OBJECTIVE: To compare treatment patterns and economic outcomes of dasatinib and nilotinib as 1st-line therapies for chronic myeloid leukemia (CML). METHODS: Adult CML patients initiated on first-line dasatinib or nilotinib in 2010-2014 were identified from two large US administrative claims databases. Treatment patterns, tyrosine kinase inhibitor (TKI) adherence and healthcare resource utilization (HRU) and costs were measured from the 1st-line TKI initiation (index date) to the end of follow-up. RESULTS: A total of 604 and 418 patients were included in the dasatinib and nilotinib cohorts (mean ages = 50.9 and 52.5 years, 46.4% and 45.7% female), respectively. Among the dasatinib patients, 91% started with 100 mg/day, 3% with <100 mg/day, and 6% with >100 mg/day. Among the nilotinib patients, 76% started with 600 mg/day, 16% with >600 mg/day, and 8% <600 mg/day. The dasatinib cohort had a higher hazard of dose decrease (hazard ratio [HR] = 1.66; p = .002) and of switching to another TKI (HR =1.62; p = .019) compared to the nilotinib cohort. The hazard of dose increase (HR =0.76; p = .423) and treatment discontinuation (HR =1.10; p = .372) were not significantly different between cohorts. There was also no significant difference in TKI adherence levels (mean proportion of days covered [PDC] difference over first 6 months = -0.0003, p = .981; mean PDC difference over first 12 months = -0.0022, p = .880) and HRU (inpatient day incidence rate ratio [IRR] = 1.03, p = .930; emergency room IRR =1.26, p = .197; and days with outpatient services IRR = 1.01, p = .842). The dasatinib cohort incurred higher healthcare costs by $749 per patient per month (p = .044) compared to the nilotinib cohort. LIMITATION: Information on CML phase and Sokal score was not available. CONCLUSIONS: Dasatinib was associated with an increased hazard of dose decrease and switching to another TKI and higher healthcare costs, vs nilotinib.


Assuntos
Dasatinibe/economia , Custos de Cuidados de Saúde , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Padrões de Prática Médica , Inibidores de Proteínas Quinases/economia , Pirimidinas/economia , Estudos de Coortes , Estudos Transversais , Dasatinibe/uso terapêutico , Feminino , Humanos , Revisão da Utilização de Seguros , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Estados Unidos
12.
Integr Environ Assess Manag ; 12(3): 559-71, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26331624

RESUMO

Pesticide transport by surface runoff depends on climate, agricultural practices, topography, soil characteristics, crop type, and pest phenology. To accurately assess the impact of climate change, these factors must be accounted for in a single framework by integrating their interaction and uncertainty. This article presents the development and application of a framework to assess the impact of climate change on pesticide transport by surface runoff in southern Québec (Canada) for the 1981-2040 period. The crop enemies investigated were: weeds for corn (Zea mays); and for apple orchard (Malus pumila), 3 insect pests (codling moth [Cydia pomonella], plum curculio [Conotrachelus nenuphar], and apple maggot [Rhagoletis pomonella]), 2 diseases (apple scab [Venturia inaequalis], and fire blight [Erwinia amylovora]). A total of 23 climate simulations, 19 sites, and 11 active ingredients were considered. The relationship between climate and phenology was accounted for by bioclimatic models of the Computer Centre for Agricultural Pest Forecasting (CIPRA) software. Exported loads of pesticides were evaluated at the edge-of-field scale using the Pesticide Root Zone Model (PRZM), simulating both hydrology and chemical transport. A stochastic model was developed to account for PRZM parameter uncertainty. Results of this study indicate that for the 2011-2040 period, application dates would be advanced from 3 to 7 days on average with respect to the 1981-2010 period. However, the impact of climate change on maximum daily rainfall during the application window is not statistically significant, mainly due to the high variability of extreme rainfall events. Hence, for the studied sites and crop enemies considered, climate change impact on pesticide transported in surface runoff is not statistically significant throughout the 2011-2040 period. Integr Environ Assess Managem 2016;12:559-571. © Her Majesty the Queen in Right of Canada 2015; Published 2015 SETAC.


Assuntos
Mudança Climática , Monitoramento Ambiental/métodos , Praguicidas/análise , Poluentes Químicos da Água/análise , Agricultura , Canadá , Malus , Movimentos da Água , Poluição Química da Água/estatística & dados numéricos , Zea mays
13.
PLoS One ; 10(3): e0118583, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25774674

RESUMO

In eastern Canada, the destruction of kelp beds by dense aggregations (fronts) of the omnivorous green sea urchin, Strongylocentrotus droebachiensis, is a key determinant of the structure and dynamics of shallow reef communities. Recent studies suggest that hydrodynamic forces, but not sea temperature, determine the strength of urchin-kelp interactions, which deviates from the tenets of the metabolic theory of ecology (MTE). We tested the hypothesis that water temperature can predict short-term kelp bed destruction by S. droebachiensis in calm hydrodynamic environments. Specifically, we experimentally determined relationships among water temperature, body size, and individual feeding in the absence of waves, as well as among wave velocity, season, and aggregative feeding. We quantified variation in kelp-bed boundary dynamics, sea temperature, and wave height over three months at one subtidal site in Newfoundland to test the validity of thermal tipping ranges and regression equations derived from laboratory results. Consistent with the MTE, individual feeding during early summer (June-July) obeyed a non-linear, size- and temperature-dependent relationship: feeding in large urchins was consistently highest and positively correlated with temperature <12°C and dropped within and above the 12-15°C tipping range. This relationship was more apparent in large than small urchins. Observed and expected rates of kelp loss based on sea temperature and urchin density and size structure at the front were highly correlated and differed by one order of magnitude. The present study speaks to the importance of considering body size and natural variation in sea temperature in studies of urchin-kelp interactions. It provides the first compelling evidence that sea temperature, and not only hydrodynamic forces, can predict kelp bed destruction by urchin fronts in shallow reef communities. Studying urchin-seaweed-predator interactions within the conceptual foundations of the MTE holds high potential for improving capacity to predict and manage shifts in marine food web structure and productivity.


Assuntos
Recifes de Corais , Comportamento Alimentar/fisiologia , Cadeia Alimentar , Strongylocentrotus/fisiologia , Animais , Tamanho Corporal , Hidrodinâmica , Kelp , Terra Nova e Labrador , Densidade Demográfica , Temperatura
14.
PLoS One ; 9(5): e98204, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24859311

RESUMO

Models of benthic community dynamics for the extensively studied, shallow rocky ecosystems in eastern Canada emphasize kelp-urchin interactions. These models may bias the perception of factors and processes that structure communities, for they largely overlook the possible contribution of other seaweeds to ecosystem resilience. We examined the persistence of the annual, acidic (H2SO4), brown seaweed Desmarestia viridis in urchin barrens at two sites in Newfoundland (Canada) throughout an entire growth season (February to October). We also compared changes in epifaunal assemblages in D. viridis and other conspicuous canopy-forming seaweeds, the non-acidic conspecific Desmarestia aculeata and kelp Agarum clathratum. We show that D. viridis can form large canopies within the 2-to-8 m depth range that represent a transient community state termed "Desmarestia bed". The annual resurgence of Desmarestia beds and continuous occurrence of D. aculeata and A. clathratum, create biological structure for major recruitment pulses in invertebrate and fish assemblages (e.g. from quasi-absent gastropods to >150,000 recruits kg(-1) D. viridis). Many of these pulses phase with temperature-driven mass release of acid to the environment and die-off in D. viridis. We demonstrate experimentally that the chemical makeup of D. viridis and A. clathratum helps retard urchin grazing compared to D. aculeata and the highly consumed kelp Alaria esculenta. In light of our findings and related studies, we propose fundamental changes to the study of community shifts in shallow, rocky ecosystems in eastern Canada. In particular, we advocate the need to regard certain canopy-forming seaweeds as structuring forces interfering with top-down processes, rather than simple prey for keystone grazers. We also propose a novel, empirical model of ecological interactions for D. viridis. Overall, our study underscores the importance of studying organisms together with cross-scale environmental variability to better understand the factors and processes that shape marine communities.


Assuntos
Ecossistema , Kelp/fisiologia , Ouriços-do-Mar/fisiologia , Estações do Ano , Animais
15.
Integr Environ Assess Manag ; 10(3): 429-36, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24644152

RESUMO

Periodic assessments of the risk of water contamination by pesticides help decision makers improve the sustainability of agricultural management practices. In Canada, when evaluating the risk of water contamination by pesticides, 2 main constraints arise. First, because the area of interest is large, a pesticide transport model with low computational running time is mandatory. Second, some relevant input data for simulations are not known, and most are known only at coarse scale. This study aims to develop a robust methodology to estimate the evolution of the risk of water contamination by pesticides across Canada. To circumvent the 2 aforementioned issues, we constructed a stochastic model and coupled it to the 1-dimensional pesticide fate model Pesticide Root Zone Model (PRZM). To account for input data uncertainty, the stochastic model uses a Monte Carlo approach to generate several pesticide application scenarios and to randomly select PRZM parameter values. One hundred different scenarios were simulated for each of over 2000 regions (Soil Landscapes of Canada [SLC] polygons) for the years 1981 and 2006. Overall, the results indicated that in those regions in which the risk increased from 1981 to 2006, the increase in risk was mainly attributable to the increased area treated by pesticides or an increase in the number of days with runoff. More specifically, this work identifies the areas at higher risk, where further analyses with finer-scale input data should be performed. The model is specific for Canadian data, but the framework could be adapted for other large countries.


Assuntos
Modelos Teóricos , Praguicidas/análise , Poluentes Químicos da Água/análise , Poluição da Água/análise , Canadá , Risco
16.
Int J Otolaryngol ; 2010: 907960, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20628529

RESUMO

Background. Lhermitte's sign (LS) is a benign form of myelopathy with neck flexion producing an unpleasant electric-shock sensation radiating down the extremities. Although rare, it can occur after head and neck radiotherapy. Results. We report a case of Lhermitte's developing after curative intensity-modulated radiotherapy (IMRT) for a patient with locoregionally advanced oropharyngeal cancer. IMRT delivers a conformal dose of radiation in head and neck cancer resulting in a gradient of radiation dose throughout the spinal cord. Using IMRT, more dose is delivered to the anterior spinal cord than the posterior cord. Conclusions. Lhermitte's sign can develop after IMRT for head and neck cancer. We propose an anterior spinal cord structure, the spinothalamic tract to be the target of IMRT-caused LS.

17.
Head Neck ; 31(6): 829-32, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18853452

RESUMO

BACKGROUND: Angiosarcoma arising after radiation is described in breast cancer but occurs elsewhere. Here, we present an angiosarcoma of the neck occurring after curative chemoradiation. METHODS: This is a case of angiosarcoma developing 5 years after curative therapy for T3N0 squamous cell carcinoma of the supraglottic larynx. Therapy consisted of 3 cycles of induction cisplatin/5-fluorouracil chemotherapy followed by radiotherapy. The patient did well until developing a rapidly progressive lesion of the left neck. Examination showed a 7-cm mass and biopsy revealed angiosarcoma. CT scans assessed the local extent of the tumor and ruled out metastatic disease prior to initiating therapy. RESULTS: Therapy consisted of 4 cycles of paclitaxel chemotherapy. At completion, examination revealed mild induration of the neck with near-complete resolution of the mass. Imaging confirmed this excellent response. CONCLUSION: This rare therapy-related second malignancy developed after curative larynx-preserving treatment. Paclitaxel was an effective therapy in this setting.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/terapia , Hemangiossarcoma/etiologia , Neoplasias Laríngeas/terapia , Radioterapia de Alta Energia/efeitos adversos , Neoplasias Cutâneas/etiologia , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Biópsia por Agulha , Carcinoma de Células Escamosas/patologia , Seguimentos , Hemangiossarcoma/tratamento farmacológico , Hemangiossarcoma/patologia , Humanos , Imuno-Histoquímica , Neoplasias Laríngeas/patologia , Masculino , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Radioterapia de Alta Energia/métodos , Indução de Remissão , Medição de Risco , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Resultado do Tratamento
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