935 resultados para Duration of studies


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Earthworms perform a number of essential functions in soil; the impacts of metals on earthworms are often investigated. In this review we consider the range of earthworm species, types of soil and forms of metal for which metal uptake and accumulation have been studied, the design of these experiments and the quantitative relationships that have been derived to predict earthworm metal body burden. We conclude that there is a need for more studies on earthworm species other than Eisenia fetida in order to apply the large existing database on this earthworm to other, soil dwelling species. To aid comparisons between studies agreement is needed on standard protocols that define exposure and deputation periods and the parameters, such as soil solution composition, soil chemical and physical properties to be measured. It is recommended that more field or terrestrial model ecosystem studies using real contaminated soil rather than metal-amended artificial soils are performed. (c) 2006 Elsevier Ltd. All rights reserved.

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The van der Heijden Studies Database has been reviewed to identify 'Draw Studies' with sub-7-man positions in the main line which are not draws. The data-mining method is described. Some 1,500 studies were faulted, 700 for the first time: 14 of the more interesting faults are highlighted and discussed.

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The van der Heijden Studies Database (Version III) has been reviewed to identify 'Win Studies' with sub-7-man positions in the main line which are not wins for White. Some studies were faulted, A number for the first time: 21 of the more interesting escapes by Black are highlighted, themed and discussed.

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The precise role of cell cycle-dependent molecules in controlling the switch from cardiac myocyte hyperplasia to hypertrophy remains to be determined. We report that loss of p27(KIP1) in the mouse results in a significant increase in heart size and in the total number of cardiac myocytes. In comparison to p27(KIP1)+/+ myocytes, the percentage of neonatal p27(KIP1)-/- myocytes in S phase was increased significantly, concomitant with a significant decrease in the percentage of G(0)/G(1) cells. The expressions of proliferating cell nuclear antigen, G(1)/S and G(2)/M phase-acting cyclins, and cyclin-dependent kinases (CDKs) were upregulated significantly in ventricular tissue obtained from early neonatal p27(KIP1)-/- mice, concomitant with a substantial decrease in the expressions of G(1) phase-acting cyclins and CDKs. Furthermore, mRNA expressions of the embryonic genes atrial natriuretic factor and alpha-skeletal actin were detectable at significant levels in neonatal and adult p27(KIP1)-/- mouse hearts but were undetectable in p27(KIP1)+/+ hearts. In addition, loss of p27(KIP1) was not compensated for by the upregulation of other CDK inhibitors. Thus, the loss of p27(KIP1) results in prolonged proliferation of the mouse cardiac myocyte and perturbation of myocyte hypertrophy.

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This article clarifies what was done with the sub-7-man positions in data-mining Harold van der Heijden's 'HHdbIV' database of chess studies prior to its publication. It emphasises that only positions in the main lines of studies were examined and that the information about uniqueness of move was not incorporated in HHdbIV. There is some reflection on the separate technical and artistic dimensions of study evaluation.

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The survival, absolute population size, gonotrophic cycle duration, and temporal and spatial abundance of Nyssomyia neivai (Pinto) were studied in a rural area endemic for American cutaneous leishmaniasis (ACL) in Conchal, Sao Paulo State, southeastern Brazil, using mark-release-recapture techniques and by monitoring population fluctuation. The monthly abundance exhibited a unimodal pattern, with forest and domicile habitats having the highest relative abundances. A total of 1,873 males and 3,557 females were marked and released during the six experiments, of which 4.1-13.0% of males and 4.1-11.8% of females were recaptured. Daily survivorship estimated from the decline in recaptures per day was 0.681 for males and 0.667 for females. Gonotrophic cycle duration was estimated to be 4.0 d. Absolute population size was calculated using the Lincoln Index and ranged from 861 to 4,612 males and from 2,187 to 19,739 females. The low proportion of females that reach the age when they are potentially infective suggests that N. neivai has a low biological capacity to serve as a vector and that factors such as high biting rates and opportunistic feeding behavior would be needed to enable Leishmania (Viannia) braziliensis Vianna transmission. This agreed with the epidemiological pattern of ACL in southeastern Brazil that is characterized by low incidence, with isolated cases acquired principally within domiciliary habitats.

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Purpose: To evaluate the duration of the effect of mepivacaine when hyaluronidase is injected immediately prior to the end of pulpal anesthesia. Patients and Methods: Forty bilateral, symmetrical third molar surgeries were performed in 20 healthy patients. Inferior alveolar nerve block was induced using 2.8 mL 2% mepivacaine with epinephrine. Hyaluronidase (75 turbidity-reducing units) or a placebo was injected 40 minutes after the beginning of pulpar anesthesia (randomized and double-blind trial). The duration of effect in the pulpal and gingival tissues was evaluated by response to painful electrical stimuli applied to the Adjacent premolar, and by mechanical stimuli (pin prick) to the vestibular gingiva, respectively. Results: in both tissues, the duration of anesthetic effect with hyaluronidase was longer (P <.01) than with the placebo. Conclusion: Hyaluronidase increases the duration of mepivacaine in inferior alveolar nerve blocks. (c) 2008 American Association of Oral and Maxillofacial Surgeons.

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This study used quantitative and qualitative techniques to examine the role of health, age, and duration of illness among people with multiple sclerosis (MS) in their economic well-being. Participants were 113 adults (31 males and 82 females) with MS who lived in urban and rural regions of Australia. The results demonstrated that health and age had a significant impact on both the economic well-being and psychological adjustment of people who contract this disorder. Different health variables predicted different aspects of economic well-being. Fatigue was the major health variable that predicted costs of MS and economic pressure, with age also predicting economic pressure, whereas income levels were predicted by cognitive confusion and mobility problems. Duration of illness, gender, and urban/rural location were not significant predictors of the economic variables. These results demonstrate the importance of obtaining multiple measures of economic well-being, as well as a broad range of health-related measures, in determining the impact of MS on the economic well-being of people with this disorder.

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The current study investigated the association between the severity and duration of physical disability and body esteem. A total of 748 participants (367 males, 381 females) who had a physical disability and 448 participants (171 males, 277 females) who were able-bodied participated in the study. The results demonstrated that people with more severe physical disability experienced lower levels of body esteem than people with milder physical disabilities and able-bodied people. The duration of physical disability was not related to levels of body esteem. Except for the face, people with physical disabilities devalued all aspects of their body more than able-bodied people. For males with physical disability, the unique predictors of high body esteem were decreased need for assistance, higher self-esteem, lower depression and higher sexual esteem; for females with physical disability, the unique predictors were higher self-esteem and higher sexual esteem. Overall, the study suggested that people with physical disability, particularly those with severe disabilities, may be particularly vulnerable to problems associated with their body esteem.

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The duration of periods spent ashore versus foraging at sea, diving behaviour, and diet of lactating female Antarctic (Arctocephalus gazella, AFS) and subantarctic (A. tropicalis, SFS) fur seals were compared at Iles Crozet, where both species coexist. The large disparity in lactation duration (SFS: 10 months, AFS: 4 months), even under local sympatry, has led to the expectation that AFS should exhibit higher foraging effort or efficiency per unit time than SFS to allow them to wean their pups in a shorter period of time. Previous evidence, however, has not supported these expectations. In this study, the distribution of foraging trip durations revealed two types of trips: overnight (OFT, <1 day) and long (LFT, >1 day), in common with other results from Macquarie Island. However, diving behaviour differed significantly between foraging trip types, with greater diving effort in OFTs than in LFTs, and diving behaviour differed between fur seal species. OFTs were more frequent in SFS (48%) than in AFS (28%). SFS performed longer LFTs and maternal attendances than AFS, but spent a smaller proportion of their foraging cycle at sea (66.2 vs. 77.5%, respectively). SFS dove deeper and for longer periods than AFS, in both OFTs and LFTs, although indices of diving effort were similar between species. Diel variation in diving behaviour was lower among SFS, which foraged at greater depths during most of the night time available than AFS. The diving behaviour of AFS suggests they followed the nychthemeral migration of their prey more closely. Concomitant with the differences in diving behaviour, AFS and SFS fed on the same prey species, but in different proportions of three myctophid fish (Gymnoscopelus fraseri, G. piabilis, and G. nicholsi) that represented most of their diet. The estimated size of the most important fish consumed did not vary significantly between fur seal species, suggesting that the difference in dive depth was mostly a result of changes in the relative abundance of these myctophids. The energy content of these fish at Iles Crozet may thus influence the amount and quality of milk delivered to pups of each fur seal species. These results contrast with those found at other sites where both species coexist, and revealed a scale of variation in foraging behaviour which did not affect their effort while at sea, but that may be a major determinant of foraging efficiency and, consequently, maternal investment.