955 resultados para Acc rate P
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This dataset includes basic information (location and depth) and major ion chemistry (Sodium, Chloride, Calcium, Nitrate) of snow cores from East Antarctic ice sheet. The snow cores were collected from two different regions - central Dronning Maud Land (cDML) and Princess Elizabeth Land (PEL) during the austral summer of 2008-09.
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Composition and accumulation rates of organic carbon in Holocene sediments provided data to calculate an organic carbon budget for the Laptev Sea continental margin. Mean Holocene accumulation rates in the inner Laptev Sea vary between 0.14 and 2.7 g C cm**2/ky; maximum values occur close to the Lena River delta. Seawards, the mean accumulation rates decrease from 0.43 to 0.02 g C cm**2/ky. The organic matter is predominantly of terrigenous origin. About 0.9*10**6 t/year of organic carbon are buried in the Laptev Sea, and 0.25*10**6 t/year on the continental slope. Between about 8.5 and 9 ka, major changes in supply of terrigenous and marine organic carbon occur, related to changes in coastal erosion, Siberian river discharge, and/or Atlantic water inflow along the Eurasian continental margin.
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The Northern Bay of Bengal (NBoB) is a globally important region for deep-sea organic matter (OM) deposition due to massive fluvial discharge from the Ganges-Brahmaputra-Meghna (G-B-M) rivers and moderate to high surface productivity. Previous studies have focused on carbon burial in turbiditic sediments of the Bengal Fan. However, little is known about the storage of carbon in pelagic and hemipelagic sediments of the Bay of Bengal over millennial time scales. This study presents a comprehensive history of OM origin and fate as well as a quantification of carbon sediment storage in the Eastern Bengal Slope (EBS) during the last 18 ka. Bulk organic proxies (TOC, TIC, TN, d13CTOC, d15NTN) and content and composition of total hydrolysable amino acids (THAA) in a sediment core (SO188-342KL) from the EBS were analyzed. Three periods of high OM accumulation were identified: the Late Glacial (LG), the Bölling/Alleröd (B/A), and the Early Holocene Climatic Optimum (EHCO). Lower eustatic sea level before 15 ka BP allowed a closer connection between the EBS and the fluvial debouch, favoring high terrestrial OM input to the core site. This connection was progressively lost between 15 and 7 ka BP as sea level rose to its present height and terrestrial OM input decreased considerably. Export and preservation of marine OM was stimulated during periods of summer monsoon intensification (B/A and EHCO) as a consequence of higher surface productivity enhanced by cyclonic-eddy nutrient pumping and fluvial nutrient delivery into the photic zone. Changes in the THAA composition indicate that the marine plankton community structure shifted from calcareous-dominated before 13 ka BP to siliceous-dominated afterwards. They also indicate that the relative proportion of marine versus terrestrial OM deposited at site 342KL was primarily driven by relative sea level and enlarged during the Holocene. The ballasting effect of lithogenic particles during periods of high coastal proximity and/or enhanced fluvial discharge promoted the export and preservation of OM. The high organic carbon accumulation rates in the EBS during the LG (18-17 ka BP) were 5-fold higher than at present and comparable to those of glacial upwelling areas. Despite the differences in sediment and OM transport and storage among the Western and Eastern sectors of the NBoB, this region remains important for global carbon sequestration during sea level low-stands. In addition, the summer monsoon was a key promotor of terrestrial and marine OM export to the deep-ocean, highlighting its relevance as regulator of the global carbon budget.
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Sediment cores from the Western Mediterranean Sea (WMS) have been analyzed for their bulk element composition, delta18O values of planktic foraminiferal tests, and 87Sr/86Sr and 143Nd/144Nd ratios of their bulk lithogenic components. The investigated time interval comprises the last 215 kyr. Si/Al and Ti/Al ratios as well as radiogenic isotope compositions indicate changes in the provenance of the lithogenic components between glacial intervals and interglacial phases. Comparison with modern data indicates that detrital input from the northwestern and northeastern Sahara may have dominated during interglacial phases. In contrast, during glacial periods the accumulation rate of terrigenous sediment is high and changes in the sediment source areas are evident that may be related to changes in the prevailing atmospheric circulation over the basin and its source areas. A productivity reconstruction based on bio-mediated barium accumulation rates reveals increased surface productivity during glacial phases. Intervals time-equivalent to sapropel formation in the Eastern Mediterranean Sea (EMS) show no changes in surface productivity compared to the intervening intervals. Comparison of the productivity patterns between the WMS and EMS suggests a decoupling during Late Pleistocene sapropel formation and highlights the importance of more localized factors such as the freshwater drainage basin.
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The Arctic is responding more rapidly to global warming than most other areas on our planet. Northward flowing Atlantic Water is the major means of heat advection towards the Arctic and strongly affects the sea ice distribution. Records of its natural variability are critical for the understanding of feedback mechanisms and the future of the Arctic climate system, but continuous historical records reach back only ~150 years. Here, we present a multidecadal scale record of ocean temperature variations during the last 2000 years, derived from marine sediments off Western Svalbard (79°N). We find that early-21st-century temperatures of Atlantic Water entering the Arctic Ocean are unprecedented over the past 2000 years and are presumably linked to the Arctic Amplification of global warming.
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This study presents aggradation rates supplemented for the first time by carbonate accumulation rates from Mediterranean cold-water coral sites considering three different regional and geomorphological settings: (i) a cold-water coral ridge (eastern Melilla coral province, Alboran Sea), (ii) a cold-water coral rubble talus deposit at the base of a submarine cliff (Urania Bank, Strait of Sicily) and (iii) a cold-water coral deposit rooted on a predefined topographic high overgrown by cold-water corals (Santa Maria di Leuca coral province, Ionian Sea). The mean aggradation rates of the respective cold-water coral deposits vary between 10 and 530 cm kyr?1 and the mean carbonate accumulation rates range between 8 and 396 g cm?2 kyr?1 with a maximum of 503 g cm?2 kyr?1 reached in the eastern Melilla coral province. Compared to other deep-water depositional environments the Mediterranean cold-water coral sites reveal significantly higher carbonate accumulation rates that were even in the range of the highest productive shallow-water Mediterranean carbonate factories (e.g. Cladocora caespitosa coral reefs). Focusing exclusively on cold-water coral occurrences, the carbonate accumulation rates of the Mediterranean cold-water coral sites are in the lower range of those obtained for the prolific Norwegian coral occurrences, but exhibit much higher rates than the cold-water coral mounds off Ireland. This study clearly indicates that cold-water corals have the potential to act as important carbonate factories and regional carbonate sinks within the Mediterranean Sea. Moreover, the data highlight the potential of cold-water corals to store carbonate with rates in the range of tropical shallow-water reefs. In order to evaluate the contribution of the cold-water coral carbonate factory to the regional or global carbonate/carbon cycle, an improved understanding of the temporal and spatial variability in aggradation and carbonate accumulation rates and areal estimates of the respective regions is needed.
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<p>Purpose: To clarify the most appropriate treatment regimen for congenital nasolacrimal duct obstruction (CNLDO). Methods: A retrospective observational analysis was performed of patients undergoing probing with or without intubation to treat CNLDO in a single institution (Royal Victoria Hospital, Belfast) from 2006 to 2011. Results: Based on exclusion criteria, 246 eyes of 177 patients (aged 0 to 9.8 years with a mean age of 2.1 years) were included in this study: 187 (76%) eyes had successful outcome at first intervention with primary probing, whereas 56 (23%) eyes underwent secondary intervention. There were no significant differences by gender, age, or obstruction complexity between the successful and unsuccessful patients with first intervention. For those patients requiring secondary intervention, 16 of 24 (67%) eyes had successful probing, whereas 22 of 24 (92%) had successful intubation. Patients with intubation as a secondary procedure were significantly more likely to have a successful outcome (P = .037). Statistical analysis was performed using the Fisher's exact test and Barnard's exact test. Conclusions: Primary probing for CNLDO has a high success rate that is not adversely affected by increasing age. This study also indicates that if initial probing is unsuccessful, nasolacrimal intubation rather than repeat probing yields a significantly higher success rate.p>
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<p>[EN]This paper describes a face detection system which goes beyond traditional approaches normally designed for still images. First the video stream context is considered to apply the detector, and therefore, the resulting system is designed taking into consideration a main feature available in a video stream, i.e. temporal coherence. The resulting system builds a feature based model for each detected face, and searches them using various model information in the next frame. The results achieved for video stream processing outperform Rowley-Kanade's and Viola-Jones' solutions providing eye and face data in a reduced time with a notable correct detection rate.p>
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The aim of this study was to investigate whether rinsing the mouth with a carbohydrate solution could improve skill-specific fencing performance and cognitive function following a fatigue inducing simulated bout of fencing in epee fencers. Eleven healthy, competitive epee fencers (three female; eight male; 33.9 ± 14.7 years; body mass 79 ± 16 kg; height 162 ± 54 cm) volunteered to participant in a single-blind crossover design study. During visit 1 participants completed a 1-minute lunge test and stroop test pre and post fatigue inducing fencing protocol. A 30 second electroencephalography (EEG) recording was taken pre-protocol participants were instructed stay in a seated stationary position with their eyes closed. Heart rate and ratings of perceived exertion were recorded following each fight during the fatiguing protocol. Participants mouth rinsed (10 seconds) either 25ml of a 6.7% maltodextrin solution (CHO) or 25ml of water (placebo) between fights and during the EEG recording. Blood lactate and glucose measurements were taken at baseline, pre and post protocol. All measurements and tests were repeated during a 2nd visit to the laboratory, except participants were given a different solution to mouth rinse, separated by a minimum of 5 days. The results showed an increase in heart rate (P < 0.05) and overall RPE (P < 0.001) over time in both trials. There were no recorded differences in blood glucose (F(1,8) = 0.634, P = 0.4, ηp 0.07) or blood lactate levels (F(1,8) = 0.123, P = 0.7, ηp 0.01) between trials. There was a significant improvement in lunge test accuracy in the CHO trial (F(1,8) = 5.214, P = 0.05, ηp 0.40). However, there was no recorded difference in response time to congruent (F(1,8) = 0.326, P = 0.58, ηp 0.04) or incongruent (F(1,8) = 0.189, P = 0.68, ηp 0.02) stimuli between trials. In conclusion mouth rinsing a CHO solution significantly improves accuracy of skill-specific fencing performance but does not affect cognitive function following a fatigue inducing fencing protocol in epee fencers.
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Background. Surgical treatment of varicose veins of the lower limbs resolves symptoms and improves quality of life. However, the high recurrence (20-80%) is a costly and complex issue. Patients and methods. This is a retrospective review of 1489 patients with varicose vein of the lower limbs seen at our hospital between January 1980 and December 2005. The aim is to evaluate the effect of surgical technique (stripping vs. CHIVA) and surgeon’s experience in reducing recurrences. Results. With experienced surgeons, CHIVA appears to be more effective than stripping in reducing the recurrence rate (p <0.05). However, when performed by an inexperienced surgeon the results are far worse than those achieved with stripping. Conclusion. There was a clear reduction in recurrences at 5-10 years with CHIVA than with conventional stripping. However, if performed incorrectly, results are far worse with CHIVA. In fact, good results are far more difficult to achieve with CHIVA than with stripping, which is repeatable and easy to perform.
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Objectives: To develop a procedure for management of off-label medications, and to analyze the treatments, indications, and hospital units which will request them more frequently, as well as which variables will have an impact on the authorization decision, and its economic impact. Methods: A procedure was designed where clinicians would complete request forms and the Hospital Unit would prepare reports assessing their efficacy, safety, convenience, and cost. The request forms for the past five years were analyzed. Results: A total of 834 applications were received, and 88.1% of these were accepted. The authorization rates were higher for Paediatric Units (95.7% vs. 86.6%; p<0.05). The reasons for considering prescriptions as off-label were: different indication (73.2%), different combination (10.2%), different line of treatment (8.6%) and different age (8%). A 73.4% of requests were for antineoplastic drugs, and the most frequently prescribed were rituximab (120) and bevacizumab (103). The quality of evidence supporting the prescriptions was moderate-low, though no direct relationship with the likelihood of approval was demonstrated (p = 0.413). The cost of the approved medications was 8,567,537 , and the theoretical savings for those drugs rejected was of 2,268,642 . There was a statistically significant decrease in the authorization rate (p < 0.05, Student's t test) when spending increased. Conclusions: The responsibility for assessing off-label prescriptions has fallen on the Pharmacy Unit. It has not been demonstrated that the quality of evidence represents a decisive variable for approval of treatment; on the other hand, age and cost have demonstrated a significant impact.
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The availability of African lungfish (Protopterus aethiopicus) in many communities in Uganda is declining. Indigenous efforts to culture this fish usually produce poor yields and depend on feeding fish fry, minced meat, and leftover food. This study evaluates three formulated diets (diet-1, diet-2, diet-3) fed to wild caught lungfish fingerlings reared in indoor tanks for 77 days. Experimental fish gradually accepted sinking pellets, and marginal increases in average body weight were observed. Mean (± SE) final weight (15.86 ± 0.80 g) for fish fed on diet-3 was significantly higher (p < 0.05) than fish fed diet-1 and diet-2. Specific growth rates (SGR) for diet- 3 were significantly higher (p < 0.05) than diet-1, and marginally more than diet-2 (0.37 ± 0.04 %/ d). Feed conversions were similar (p >0.05), ranging from 1.61 ± 0.26 to 2.07 ± 0.11. Survivals after an 11-week culture were relatively low (< 60%), but generally increased (R2 = 0.667, P = 0.007) with increasing dietary proteins. Diet-3 had a significant higher survival rate (p< 0.05) than diet-1 and diet-2. Significant growth performance was attained with diet-3. This study demonstrated that sinking fish feed pellets can be used to culture wild-caught African fingerlings in captivity.
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Common bottlenose dolphins (Tursiops truncatus), produce a wide variety of vocal emissions for communication and echolocation, of which the pulsed repertoire has been the most difficult to categorize. Packets of high repetition, broadband pulses are still largely reported under a general designation of burst-pulses, and traditional attempts to classify these emissions rely mainly in their aural characteristics and in graphical aspects of spectrograms. Here, we present a quantitative analysis of pulsed signals emitted by wild bottlenose dolphins, in the Sado estuary, Portugal (2011-2014), and test the reliability of a traditional classification approach. Acoustic parameters (minimum frequency, maximum frequency, peak frequency, duration, repetition rate and inter-click-interval) were extracted from 930 pulsed signals, previously categorized using a traditional approach. Discriminant function analysis revealed a high reliability of the traditional classification approach (93.5% of pulsed signals were consistently assigned to their aurally based categories). According to the discriminant function analysis (Wilk's Λ = 0.11, F3, 2.41 = 282.75, P < 0.001), repetition rate is the feature that best enables the discrimination of different pulsed signals (structure coefficient = 0.98). Classification using hierarchical cluster analysis led to a similar categorization pattern: two main signal types with distinct magnitudes of repetition rate were clustered into five groups. The pulsed signals, here described, present significant differences in their time-frequency features, especially repetition rate (P < 0.001), inter-click-interval (P < 0.001) and duration (P < 0.001). We document the occurrence of a distinct signal type-short burst-pulses, and highlight the existence of a diverse repertoire of pulsed vocalizations emitted in graded sequences. The use of quantitative analysis of pulsed signals is essential to improve classifications and to better assess the contexts of emission, geographic variation and the functional significance of pulsed signals.
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Two different culture media, namely CHU12 and inorganic fertilizer NPK (20-5-20) associated with macrophyte (Eichhornia crassipes) extract, were used to evaluate the development of A. gracilis. Growth rate, development, nutritional value and medium water quality were analyzed. A. gracilis in macrophyte+NPK medium had mean cell density (333x10(5) cells/mL) higher than medium CHU12 (302x10(5) cells/mL). Protein rate (12.52% PS), dry weight (397x10(7) pg/cell) and ashes (4.08x10(7) pg/cell) in A. gracilis was higher (p<0.05) than medium macrophyte+NPK. on the other hand, lipids, carbohydrates and fibers had the same rate (p>0.05) in both media. When hydrological variables in the culture medium of A. gracilis are taken into account, dissolved oxygen and free CO2 alone failed to have any significant difference (p>0.05) between the media employed. A. gracilis in the macrophyte+NPK medium had the same nutritional rate as the commercial medium CHU12, with excellent results for alga growth. Macrophyte medium may be used for large scale alga culture in the feed of fish larvae.