83 resultados para luminous intensity


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Human subjects overestimate the change of rising intensity sounds compared with falling intensity sounds. Rising sound intensity has therefore been proposed to be an intrinsic warning cue. In order to test this hypothesis, we presented rising, falling, and constant intensity sounds to healthy humans and gathered psychophysiological and behavioral responses. Brain activity was measured using event-related functional magnetic resonance imaging. We found that rising compared with falling sound intensity facilitates autonomic orienting reflex and phasic alertness to auditory targets. Rising intensity sounds produced neural activity in the amygdala, which was accompanied by activity in intraparietal sulcus, superior temporal sulcus, and temporal plane. Our results indicate that rising sound intensity is an elementary warning cue eliciting adaptive responses by recruiting attentional and physiological resources. Regions involved in cross-modal integration were activated by rising sound intensity, while the right-hemisphere phasic alertness network could not be supported by this study.

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Mast fruiting is a distinctive reproductive trait in trees. This rain forest study, at a nutrient-poor site with a seasonal climate in tropical Africa, provides new insights into the causes of this mode of phenological patterning. •  At Korup, Cameroon, 150 trees of the large, ectomycorrhizal caesalp, Microberlinia bisulcata, were recorded almost monthly for leafing, flowering and fruiting during 1995–2000. The series was extended to 1988–2004 with less detailed data. Individual transitions in phenology were analysed. •  Masting occurred when the dry season before fruiting was drier, and the one before that was wetter, than average. Intervals between events were usually 2 or 3 yr. Masting was associated with early leaf exchange, followed by mass flowering, and was highly synchronous in the population. Trees at higher elevation showed more fruiting. Output declined between 1995 and 2000. •  Mast fruiting in M. bisulcata appears to be driven by climate variation and is regulated by internal tree processes. The resource-limitation hypothesis was supported. An ‘alternative bearing’ system seems to underlie masting. That ectomycorrhizal habit facilitates masting in trees is strongly implied.

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OBJECTIVE: Generation and maintenance of pain in chronic pancreatitis (CP) have been shown to be partially attributable to neuroimmune interactions, which involve neuropeptides such as substance P (SP). So far, expression of SP receptors NK-2R, NK-3R, the SP-encoding gene preprotachykinin A (PPT-A), and the SP degradation enzyme neutral endopeptidase (NEP) and their relation to pain in CP have not been determined. METHODS: Tissue samples from patients with CP (n = 25) and from healthy donors (n = 20) were analyzed for PPT-A, NK-2R, NK-3R, and NEP expression using quantitative RT-PCR. NEP protein levels were examined by immunoblot analysis and its localization was determined using immunohistochemistry. A scoring system was used to grade the extent of fibrosis on hematoxylin and eosin- and Masson-Trichrome-stained sections. Messenger RNA levels and the extent of pain were analyzed for correlations. RESULTS: In CP tissues, NK-2R and PPT-A expression was increased, whereas NK-3R and NEP mRNA levels were comparable with normal pancreas. Overexpression of NK-2R was related to the intensity, frequency, and duration of pain in CP patients. NK-1R and NEP expression was significantly related to the extent of fibrosis. CONCLUSIONS: Expression of NK-2R and PPT-A is increased in CP and is associated with pain. Failure to up-regulate NEP may contribute to the disruption of the neuropeptides loop balance in CP and thus may exacerbate the severe pain syndrome.

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BACKGROUND: Pain associated with routine procedures in NICUs is often inadequately managed. Barriers to more appropriate pain management are nurses' and physicians' knowledge and the challenges of collaborative decision-making. Few studies describe the differing perceptions of procedural pain intensity among nurses and physicians in NICUs which could complicate common decision-making. This study set out to explore the factors influencing pain intensity assessment and to gain insight into a possible pain intensity classification of routine procedures in the NICU. METHOD: A survey was conducted among 431 neonatal health care professionals from 4 tertiary level NICUs. Each routine procedure was assessed on a 10-point visual analogue scale (VAS) assuming absence of analgesia. RESULTS: Multiple ANCOVA models showed that nurses rated 19 of the 27 procedures as significantly more painful than did physicians (p<0.05). We found no differences in pain assessment based on professional experience, gender or age. Of the 27 procedures listed, 70% were rated as painful and 44% were judged very painful. Ranking and classification of the pain intensity of routine procedures were drawn up. The general ranking of the median across all procedures shows that "insertion of a thoracic drain" is assessed as the most painful procedure. CONCLUSIONS: The majority of routine procedures in an NICU are considered to be painful. Nurses generally rate procedures as more painful than do physicians. This difference in assessment deserves exploration in regard to its impact on collaborative decision-making in neonate pain management.

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BACKGROUND: To report acute and late toxicity in prostate cancer patients treated by dose escalated intensity-modulated radiation therapy (IMRT) and organ tracking. METHODS: From 06/2004 to 12/2005 39 men were treated by 80 Gy IMRT along with organ tracking. Median age was 69 years, risk of recurrence was low 18%, intermediate 21% and high in 61% patients. Hormone therapy (HT) was received by 74% of patients. Toxicity was scored according to the CTC scale version 3.0. Median follow-up (FU) was 29 months. RESULTS: Acute and maximal late grade 2 gastrointestinal (GI) toxicity was 3% and 8%, late grade 2 GI toxicity dropped to 0% at the end of FU. No acute or late grade 3 GI toxicity was observed. Grade 2 and 3 pre-treatment genitourinary (GU) morbidity (PGUM) was 20% and 5%. Acute and maximal late grade 2 GU toxicity was 56% and 28% and late grade 2 GU toxicity decreased to 15% of patients at the end of FU. Acute and maximal late grade 3 GU toxicity was 8% and 3%, respectively. Decreased late > or = grade 2 GU toxicity free survival was associated with higher age (P = .025), absence of HT (P = .016) and higher PGUM (P < .001). DISCUSSION: GI toxicity rates after IMRT and organ tracking are excellent, GU toxicity rates are strongly related to PGUM.

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BACKGROUND: Pain and depression are known to be associated in later life, and both have a negative effect on physical performance both separately and in combination. The nature of the relationships between pain intensity and depression in elderly persons experiencing pain is less clear. The objectives of this study were to explore which factors are associated with depressed mood in older people experiencing pain, and to test the hypothesis that older people experiencing pain are at risk of depressed mood according to the severity or frequency of their pain. In addition we explored whether other potentially modifiable factors might increase the risk of depressed mood in these persons. METHODS: The study is a secondary analysis of baseline data for four hundred and six community-dwelling non-disabled people aged 65 and over registered with three group practices in suburban London who had experienced pain in the past 4 weeks. Intensity and frequency of pain was measured using 24 item Geriatric Pain Measure (GPM) and the presence of depressive symptoms using the 5 item Mental Health Inventory. Risk for social isolation was measured using the 6 item Lubben Social Network scale and instrumental activities of daily living (IADL) were also measured. RESULTS: Overall 76 (19%) had depressed mood. Pain frequency and severity were not statistically significantly associated with depressed mood in this population. In multivariate analyses, significant predictors of the presence of depressive symptoms were difficulties with basic ADLs (OR 2.8, 95% CI 1.1.7.8), risk for social isolation (OR 4.1, 95% CI 1.8-9.3), and basic education only (OR 2.2, 95% CI 1.1-4.4). CONCLUSION: Older people experiencing pain are also likely to experience depression. Among those experiencing pain, social network and functional status seem to be more important predictors of depressive symptoms than the severity of pain. Further studies should evaluate whether improvement of social network and functional status might reduce depressive symptoms in older patients.

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BACKGROUND: Questions about the existence of supplier-induced demand emerge repeatedly in discussions about governing Swiss health care. This study therefore aimed to evaluate the interrelationship between structural factors of supply and the volume of services that are provided by primary care physicians in Switzerland. METHODS: The study was designed as a cross-sectional investigation, based on the complete claims data from all Swiss health care insurers for the year 2004, which covered information from 6087 primary care physicians and 4.7 million patients. Utilization-based health service areas were constructed and used as spatial units to analyze effects of density of supply. Hierarchical linear models were applied to analyze the data. RESULTS: The data showed that, within a service area, a higher density of primary care physicians was associated with higher mortality rates and specialist density but not with treatment intensity in primary care. Higher specialist density was weakly associated with higher mortality rates and with higher treatment intensity density of primary care physicians. Annual physician-level data indicate a disproportionate increase of supplied services irrespective of the size of the number of patients treated during the same year and, even in high volume practices, no rationing but a paradoxical inducement of consultations occurred. The results provide empirical evidence that higher densities of primary care physicians, specialists and the availability of out-patient hospital clinics in a given area are associated with higher volume of supplied services per patient in primary care practices. Analyses stratified by language regions showed differences that emphasize the effect of the cantonal based (fragmented) governance of Swiss health care. CONCLUSION: The study shows high volumes in Swiss primary care and provides evidence that the volume of supply is not driven by medical needs alone. Effects related to the competition for patients between primary care physicians, specialists and out-patient hospital clinics and an association with the system of reimbursing services on a fee-for-service basis can not be excluded.

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INTRODUCTION: To report acute and late toxicities in patients with intermediate- and high-risk prostate cancer treated with combined high-dose-rate brachytherapy (HDR-B) and intensity-modulated radiation therapy (IMRT). MATERIALS AND METHODS: From March 2003 to September 2005, 64 men were treated with a single implant HDR-B with 21 Gy given in three fractions, followed by 50 Gy IMRT along with organ tracking. Median age was 66.1 years, and risk of recurrence was intermediate in 47% of the patients or high in 53% of the patients. Androgen deprivation therapy was received by 69% of the patients. Toxicity was scored according to the CTCAE version 3.0. Median follow-up was 3.1 years. RESULTS: Acute grade 3 genitourinary (GU) toxicity was observed in 7.8% of the patients, and late grades 3 and 4 GU toxicity was observed in 10.9% and 1.6% of the patients. Acute grade 3 gastrointestinal (GI) toxicity was experienced by 1.6% of the patients, and late grade 3 GI toxicity was absent. The urethral V(120) (urethral volume receiving > or =120% of the prescribed HDR-B dose) was associated with acute (P=.047) and late > or = grade 2 GU toxicities (P=.049). CONCLUSIONS: Late grades 3 and 4GU toxicity occurred in 10.9% and 1.6% of the patients after HDR-B followed by IMRT in association with the irradiated urethral volume. The impact of V(120) on GU toxicity should be validated in further studies.