957 resultados para high dose rate


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OBJECTIVES: The aim of the Tromstannen - Oral Health in Northern Norway (TOHNN) study was to investigate oral health and dental-related diseases in an adult population. This article provides an overview of the background of the study and a description of the sample characteristics and methods employed in data collection. STUDY DESIGN: Cross-sectional population-based study including a questionnaire and clinical dental examination. METHODS: A randomly selected sample of 2,909 individuals (20-79 years old) drawn from the population register was invited to participate in the study. The data were collected between October 2013 and November 2014 in Troms County in northern Norway. The questionnaire focused on oral health-related behaviours and attitudes, oral health-related quality of life, sense of coherence, dental anxiety and symptoms from the temporomandibular joint. The dental examinations, including radiographs, were conducted by 11 dental teams in 5 dental offices. The examination comprised of registration of dental caries, full mouth periodontal status, temporomandibular disorders, mucosal lesions and height and weight. The participants were grouped by age (20-34, 35-49, 50-64 and 65-79) and ethnicity (Norwegian, Sámi, other European and other world). RESULTS: From the original sample of 2,909 individuals, 1,986 (68.3%) people participated, of whom 1,019 (51.3%) were women. The highest attendance rate was among women 20-34 years old (80.3%) and the lowest in the oldest age group of women (55.4%). There was no difference in response rate between rural and urban areas. There was a positive correlation between population size and household gross income (p < 0.001) and education level (p < 0.001). The majority of Sámi resided in smaller municipalities. In larger cities, most participants used private dental health care services, whereas, in rural areas, most participants used the public dental health care service. CONCLUSION: The TOHNN study has the potential to generate new knowledge on a wide range of oral health conditions beneficial to the population in Troms County. Due to the high participation rate, generalization both nationally and to the circumpolar area ought to be possible.

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In major economic growth theories, high saving rate gives rise to high level of output per capita. But in Keynesian economics, high saving rate causes low consumption and will lead the economy into recession. Students may ask, "For the well-being of an economy, should we save or should we consume?" In most of the intermediate macroeconomics textbooks, economic growth and Keynesian economics are taught in separate chapters; and in many cases, these chapters are not even successive to each other. There lacks a continuity between the long run and short run models. This paper builds a bridge between growth theories and Keynesian models. It links the Solow diagram and the IS-LM curves and depicts the short run and long run implications of a change in the saving rate.

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In text categorization applications, class imbalance, which refers to an uneven data distribution where one class is represented by far more less instances than the others, is a commonly encountered problem. In such a situation, conventional classifiers tend to have a strong performance bias, which results in high accuracy rate on the majority class but very low rate on the minorities. An extreme strategy for unbalanced, learning is to discard the majority instances and apply one-class classification to the minority class. However, this could easily cause another type of bias, which increases the accuracy rate on minorities by sacrificing the majorities. This paper aims to investigate approaches that reduce these two types of performance bias and improve the reliability of discovered classification rules. Experimental results show that the inexact field learning method and parameter optimized one-class classifiers achieve more balanced performance than the standard approaches.

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Laser shock peening (LSP) is an innovative surface treatment technique for metal alloys, with the great improvement of their fatigue, corrosion and wear resistance performance. Finite element method has been widely applied to simulate the LSP to provide the theoretically predictive assessment and optimally parametric design. In the current work, 3-D numerical modelling approaches, combining the explicit dynamic analysis, static equilibrium analysis algorithms and different plasticity models for the high strain rate exceeding 106s-1, are further developed. To verify the proposed methods, 3-D static and dynamic FEA of AA7075-T7351 rods subject to two-sided laser shock peening are performed using the FEA package–ABAQUS. The dynamic and residual stress fields, shock wave propagation and surface deformation of the treated metal from different material modelling approaches have a good agreement.

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The black bream Acanthopagrus butcheri recreational fishery is the largest estuarine fishery in Victoria. This fishery is managed through legal-minimum length and daily bag limits. The success of this management strategy requires a high survival rate for released fish. Deep-hooking is known to reduce the chance of fish survival after recreational capture and release. This study investigated the potential to reduce deep-hooking and the number of under-size A. butcheri caught by varying angling gear and techniques. Three sizes of long shank hook (small [size 8], medium [size 4] and large [size 1/0]) and two angling techniques (slack line and tight line) were tested for their deep-hooking rates and selectivity characteristics. Increasing the hook size from small to large decreased the likelihood of deep-hooking by 6.6 times (95% CI 2.3–16.3 times). Fishing with a tight line instead of a slack line decreased the chance of deep-hooking by almost 100% (95% CI 0.8–3.6). Fishing with a large hook instead of a small hook significantly (F = 6.71, df = 2, P = <0.001) increased the mean A. butcheri length, although this mean size increase was less than 1 cm. This study was able to identify angling gear and angling technique manipulations that reduced the rate of deep-hooking when targeting A. butcheri in Victorian estuaries.

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BACKGROUND: Last year, Australian Family Physician published Guidelines for Management of Postmenopausal Osteoporosis'. which were developed by Osteoporosis Australia. Recently, significant advances in our understanding of the treatment of corticosteroid osteoporosis have occurred.

OBJECTIVE: The following guidelines also developed by Osteoporosis Australia, and supported by the National Asthma Campaign, are to help general practitioners identify those patients at risk of this problem and to provide information about current treatment strategies.

DISCUSSION
: Corticosteroids are widely used and effective agents for the control of many inflammatory diseases. Corticosteroid osteoporosis is a common problem associated with the long term high dose use of these medications.

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Phytoplankton primary productivity of eleven irrigation reservoirs located in five river basins in Sri Lanka was determined on a single occasion together with light climate and nutrient concentrations. Although area-based gross primary productivity (1.43–11.65 g O2 m−2 d−1) falls within the range already established for tropical water bodies, net daily rate was negative in three water bodies. Light-saturated optimum rates were found in water bodies, with relatively high algal biomass, but photosynthetic efficiency or specific rates were higher in water bodies with low algal biomass, indicating nutrient limitation or physiological adaptation of phytoplankton. Concentrations of micronutrients and algal biomass in the reservoirs are largely altered by high flushing rate resulting from irrigation release. Underwater light climate and nutrient availability control the rate of photosynthesis and subsequent areabased primary production to a great extent. However, morpho-edephic index or euphotic algal biomass in the most productive stratum of the water column is not a good predictor of photosynthetic capacity or daily rate of primary production of these shallow tropical irrigation reservoirs.

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This study presents an integrated model for computing the thermo-mechanical parameters (cross-sectional shape of workpiece, the pass-by-pass strain and strain rate and the temperature variation during rolling and cooling between inter-stands) and metallurgical parameters (recrystallisation behaviour and austenite grain size—AGS), to assess the potential for developing “Thermo-Mechanical Controlled Process” technology in rod (or bar) rolling, which has been a well-known technical terminology in strip (or plate) rolling since 1970s.

The advantage of this model is that metallurgical and mechanical parameters are obtained simultaneously in a short computation time compared with other models. The model has been applied to a rod mill to predict the exit cross-sectional shape, area and AGS per pass by incorporating the equations for AGS evolution being used in strip rolling. At the finishing train of rod mills, the strain rates reach as high as 1000–3000 s−1 and the inter-pass times are around 10–60 ms.

The results show that the proposed model is an efficient tool for evaluating the effects of process-related parameters on product quality and dimensional tolerance of the products in rod (or bar) rolling. The results of the simulation demonstrated that the equation for AGS evolution being used in strip rolling might have limitations when applied directly to rod rolling at a high strain rate.


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This paper discusses some experimental results on the influence of grain refinement on the final mechanical properties of IF and microalloyed steels designed for auto-body components. It shows also some modeling approaches to understanding the dynamic behavior of fine-rained materials. The Zerilli–Armstrong (Z–A) and Khan–Huang–Liang (KHL) models for studied steels were implemented into FEM code in order to simulate the dynamic compression tests with different strain rates.

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The purpose of the current study is to evaluate the cardioprotective effects of purified Salvia miltiorrhiza extract (PSME) on myocardial ischemia/reperfusion injury in isolated rat hearts. Hearts were excised and perfused at constant flow (7 – 9 ml · min−1) via the aorta. Non-recirculating perfusion with Krebs-Henseleit (KH) solution was maintained at 37°C and continuously gassed with 95% O2 and 5% CO2. KH solution with or without PSME (100 mg per liter solution) was used after 30-min zero-flow ischemia for the PSME and control group, respectively. Left ventricular (LV) developed pressure; its derivatives, diastolic pressure, and so on were continuously recorded via a pressure transducer attached to a polyvinylchloride balloon that was placed in the left ventricle through an incision in the left atrium. PSME treated hearts showed significant postischemic contractile function recovery (developed pressure recovered to 44.2 ± 4.9% versus 17.1 ± 5.7%, P<0.05; maximum contraction recovered to 57.2 ± 5.9% versus 15.1 ± 6.3%, P<0.001; maximum relaxation restored to 69.3 ± 7.3% versus 15.4 ± 6.3%, P<0.001 in the PSME and control group, respectively). Significant elevation in end-diastolic pressure, which indicated LV stiffening in PSME hearts might have resulted from the excess high dose of PSME used. Further study will be conducted on the potential therapeutic value with lower dose of PSME on prevention of ischemic heart disease.

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Aims
Cyclophosphamide (CTX) is an established treatment of severe systemic lupus erythematosus (SLE). Cytotoxic CTX metabolites are mainly detoxified by multiple glutathione S-transferases (GSTs). However, data are lacking on the relationship between the short-term side-effects of CTX therapy and GST genotypes. In the present study, the effects of common GSTM1, GSTT1, and GSTP1 genetic mutations on the severity of myelosuppression, gastrointestinal (GI) toxicity, and infection incidences induced by pulsed CTX therapy were evaluated in patients SLE.
Methods
DNA was extracted from peripheral leucocytes in patients with confirmed SLE diagnosis (n = 102). GSTM1 and GSTT1 null mutations were analyzed by a polymerase chain reaction (PCR)-multiplex procedure, whereas the GSTP1 codon 105 polymorphism (Ile→Val) was analyzed by a PCR-restriction fragment length polymorphism (RFLP) assay.
Results
Our study demonstrated that SLE patients carrying the genotypes with GSTP1 codon 105 mutation [GSTP1*-105I/V (heterozygote) and GSTP1*-105 V/V (homozygote)] had an increased risk of myelotoxicity when treated with pulsed high-dose CTX therapy (Odds ratio (OR) 5.00, 95% confidence interval (CI) 1.96, 12.76); especially in patients younger than 30 years (OR 7.50, 95% CI 2.14, 26.24), or in patients treated with a total CTX dose greater than 1.0 g (OR 12.88, 95% CI 3.16, 52.57). Similarly, patients with these genotypes (GSTP1*I/V and GSTP1*V/V) also had an increased risk of GI toxicity when treated with an initial pulsed high-dose CTX regimen (OR 3.33, 95% CI 1.03, 10.79). However, GSTM1 and GSTT1 null mutations did not significantly alter the risks of these short-term side-effects of pulsed high-dose CTX therapy in SLE patients.
Conclusions
The GSTP1 codon 105 polymorphism, but not GSTM1 or GSTT1 null mutations, significantly increased the risks of short-term side-effects of pulsed high-dose CTX therapy in SLE patients. Because of the lack of selective substrates for a GST enzyme phenotyping study, timely detection of this mutation on codon 105 may assist in optimizing pulsed high-dose CTX therapy in SLE patients.

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Irinotecan (CPT-11, 7-ethyl-10-[4-(1-piperidino)-1-piperidino] carbonyloxycamptothecin) has exhibited clinical activities against a broad spectrum of carcinomas by inhibiting DNA topoisomerase I (Topo I). However, severe and unpredictable dosing-limiting toxicities (mainly myelosuppression and severe diarrhea) hinder its clinical use. The latter consists of early and late-onset diarrhea, occurring within 24 hr or ≥ 24 hr after CPT-11 administration, respectively. This review highlights novel agents potentially inhibiting CPT-11-induced diarrhea, which are designed and tested under guidance of disposition pathways and potential toxicity mechanisms. Early-onset diarrhea is observed immediately after CPT-11 infusion and probably due to the inhibition of acetylcholinesterase activity, which can be eliminated by administration of atropine. Lateonset diarrhea appears to be associated with intestinal exposure to SN-38 (7-ethyl-10-hydroxycamptothecin), the major active metabolite of CPT-11, which may bind to Topo I and induce apoptosis of intestinal epithelia, leading to the disturbance in the absorptive and secretory functions of mucosa. CPT-11 and SN-38 may also stimulate the production of pro-inflammatory cytokines and prostaglandins (PGs), thus inducing the secretion of Na+ and Cl-. Early treatment of severe late-onset diarrhea with oral high-dose loperamide has decreased patient morbidity. Extensive studies have been conducted to identify other potential agents to ameliorate diarrhea in preclinical and clinical models. These include intestinal alkalizing agents, oral antibiotics, enzyme inducers, P-glycoprotein (PgP) inhibitors, cyclooxygenase-2 (COX-2) inhibitors, tumor necrosis factor-agr (TNF-α) inhibitors, or blockers of biliary excretion of SN-38. Further studies are needed to identify the molecular targets associated with CPT-11 toxicity and safe and effective agents for alleviating CPT-11-induced diarrhea.

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Aims. To evaluate the effectiveness of a health promotion
programme targeting dietary behaviours and physical
activity among male hourly-paid workers and to explore
demographic and attitudinal influences on dietary patterns
at baseline.
Methods. A controlled field trial compared workers at one
intervention and one control worksite. The intervention
comprised nutrition displays in the cafeteria and monthly
30-minute workshops for six months. Key outcome
measures at six and twelve-months were self-reported
dietary and lifestyle behaviours, nutrition knowledge, body
mass index (BMI), waist circumference and blood pressure.
Results. 132 men at the intervention site and 121 men at the
control site participated in the study and a high retention rate
(94% at 6-months and 89% at 12-months) was achieved. At
baseline, 40% of the total sample (253) were obese, 30% had
elevated blood pressure, 59% indicated an excessive fat intake
and 92% did not meet the recommended vegetable and fruit
intake. The intervention reduced fat intake, increased
vegetable intake and physical activity, improved nutrition
knowledge and reduced systolic blood pressure when
compared to the control site. There was no difference in
change in mean BMI or waist circumference. Reduction in
BMI was associated with reduction in fat intake.
Discussion. Low intensity workplace intervention can
significantly improve reported health behaviours and
nutrition knowledge although the impact on more
objective measures of risk was variable. A longer duration
or more intensive intervention may be required to achieve
further reduction in risk factors.

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Cardiovascular disease (CVD) is the leading cause of death and hospitalization in both men and women in nearly all countries of Europe. The most frequent forms of CVD are those of an atherosclerotic origin, mainly ischaemic heart disease, stroke and heart failure. The magnitude of the problem contrasts with the usual paucity and poor quality of data available on incidence and prevalence of CVD, except for few rigorous but limited studies.

The objectives of the health interview and health examination surveys (HIS/HES) are to evaluate the frequency and the distribution of the disease, to evaluate trends and treatment effectiveness, to estimate risk factors distribution and prevalence of high risk conditions and to monitor prevention programmes.

According to the EUROCISS project (EUROpean Cardiovascular Surveillance Set) recommendations, surveys are aimed at describing the prevalence of the following CVD conditions: myocardial infarction, heart failure, angina pectoris, peripheral arterial disease, stroke, and ischaemic heart disease.

HIS and HES were developed to supplement information collected from routine databases and population-based registers to implement consistent public health policies. HIS can be repeated periodically in a new sample of the population, or can follow up over time the population recruited at baseline. Procedures and methods to collect information from participants include self-administered questionnaires, direct interviewer-administered questions and telephone interviews. A minimum set of questions to be administered every year, along with a longer, more detailed module to be administered periodically are recommended to evaluate CVD prevalence. The addition of HES provides more detailed and objective information that can be used to improve estimates regarding prevalence of both risk factors and disease status.

The selection of more specialized CVD-specific tests will depend on the objective the survey is designed to achieve, the assumed response rate and the cost and time considerations. For HES on CVD the minimum required is to perform the following measurements: height, weight, blood pressure, waist circumference, total and high density lipoprotein-cholesterol and glucose assay in a nonfasting blood sample. The next appropriate step would be to perform an electrocardiogram. High costs usually make HES difficult to carry out.

Standardization of measurements, training of personnel and quality control are essential to assure reliable data. A high response rate is extremely important, as nonrespondents tend to have different health characteristics from the rest of the sample and their omission therefore results in bias.

This manual of operations is intended for health professionals and policy makers and provides a standardized and simple model for the implementation of a CVD survey.

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Purpose: This paper seeks to present the second part of research funded by the RICS Education Trust to investigate the impact of the 2001 education reforms on Building Surveying. The first part of the research involved the collection of data from university course leaders.

Design/methodology/approach: This research involved the collection of data from large national, mainly London-based, employers of building surveyors at a focus group meeting.

Findings: The paper finds that issues of concern to these employers include the extent of construction technology knowledge of graduates, the delivery of contract administration, the placement year, post-graduate conversion courses and the high referral rate for the Assessment of Professional Competence (APC). Recommendations include advice to universities on the design of building surveying undergraduate and conversion courses, a call for further research on the high APC referral rate, and greater liaison between industry and universities.

Research limitations/implications
: The main limitation of the research is that the employers from whom data were collected were mainly large, national firms. Further research would be required to elicit the views of smaller regional organisations.

Practical implications: Both parts of this RICS Education Trust funded research provides a foundation for the Building Surveying Faculty of the RICS to complete their review of the education and training of building surveyors.

Originality/value: The research provides useful data on the impact of RICS education reform on building surveying, but mainly large, national firms.