962 resultados para litter fall


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Forest litter decomposition is a major process in returning nutrients to soils and thus promoting wood productivity in the humid tropic. This study aimed to assess decomposition of eucalypt litter in the Rio Doce region, Brazil. Leaf litter was sampled under clonal eucalypt stands aged 2, 4 and 6 years on hillslopes and footslopes. Soil and soil+litter samples were incubated at two levels of soil moisture, temperature and fertilization. C-CO2 emissions from soil measured during 106 days were higher at 32 °C than at 23°C, mainly for the 2-yr-old stand on footslope. When leaf litter was added on soils, C-CO2 emissions were eight times higher, mainly on footslopes, with no effect of stand age. Leaf decomposition in situ, assessed with a litterbag experiment showed a mean weight loss of at least 50% during 365 days, reaching 74% for 2 yr-old stands on footslopes. In comparison with data from the native forest and the literature, no apparent restrictions were found in eucalypt litter decomposition. Differences between in vitro and in situ results, and between eucalypt and native forest, were most likely related to the response of diverse decomposer communities and to substrate quality.

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ABSTRACT Considering the importance of the riparian vegetation leaves as an energetic source to first order streams, the aim of the present study was to evaluate the leaf biomass contribution to the system and its temporal dynamics. With this purpose, monthly samples from July 2008 to June 2009 were collected using four sampling devices installed in three streams, in order to collect the vertical, lateral and terrestrial loads, and the benthic stock. We tested the following hypothesis: (1) leaf biomass input is higher after hydric stress periods; and (2) benthic stock biomass increase with higher loads from vertical and lateral entrances. Leaves represented 71.9% (on average) of all sampled allochthonous matter, with seasonal significant variation along the studied year. Peaks of leaf input were registered in September-October, after an increase in rainfall, and also in January, after a decrease in rainfall. Leaf input was higher in the lateral load.

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ABSTRACT Considering the importance of the substrate to bedding in the poultry industry in Brazil, and the enormous pressure on environmental management as to the correct use and management of the waste generated by the production sector, this study aimed to analyze the effect of reuses of two types of litter on sanitary qualities and productive performance of broilers. The study was conducted with litter from 32 different broiler houses, two types of substrates and four cycles of reuses. The litter sanitary quality was verified by the identification of the presence of Escherichia coli and Salmonellaspp. and the incidence of footpad dermatitis. It was observed that the coffee hulls litter presented a reduction of 28.61 percentage points in the probability of occurrence of Salmonella spp when compared to the wood shavings litter, nevertheless, no statistical difference was observed on bacterial occurrence with Salmonella spp. for litter of different types or numbers of reutilization. The presence of Escherichia coli was detected in litter of all cycles, for both types of substrate. The occurrence of footpad lesions was detected for both types of litter, and was influenced by the number of reutilization cycles of the litter. The degree of incidence was detected only for the litter with coffee hull in which there was an increase of 30% between the first and second reuse from which tended to stabilize.

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Marine litter is an international environmental problem that causes considerable costs to coastal communities and the fishing industry. Several international and national treaties and regulations have provisions to marine litter and forbid disposal of waste into the sea. However, none of these regulations state a responsibility for public authorities to recover marine litter from the sea, like they do for marine litter that washes up on public beaches. In a financial evaluation of a value chain for marine litter incineration it was found out that the total costs of waste incineration are approximately 100 ─ 200 % higher than waste fees offered by waste contractors of ports. The high costs of incineration are derived from the high calorific value of marine litter and therefore a high incineration cost for the waste, and long distances between ports that are taking part in a project for marine litter recovery from the sea and an Energy-from-Waste (EfW) facility. This study provides a possible solution to diverting marine litter from landfills to more environmentally sustainable EfW use by using a public-private partnership (PPP) framework. PPP would seem to fit as a suitable cooperative approach for answering problems of current marine litter disposal in theory. In the end it is up to the potential partners of this proposed PPP to decide whether the benefits of cooperation justify the required efforts.

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OBJECTIVE: To analyze the lesions diagnosed in victims of falls, comparing them with those diagnosed in other mechanisms of blunt trauma.METHODS: We conducted a retrospective study of trauma protocol charts (prospectively collected) from 2008 to 2010, including victims of trauma over 13 years of age admitted to the emergency room. The severity of injuries was stratified by the Abbreviated Injury Scale (AIS) and Injury Severity Score (ISS). Variables were compared between the group of victims of falls from height (Group 1) and the other victims of blunt trauma (Group 2). We used the Student t, chi-square and Fisher tests for comparison between groups, considering the value of p <0.05 as significant.RESULTS: The series comprised 4,532 cases of blunt trauma, of which 555 (12.2%) were victims of falls from height. Severe lesions (AISe"3) were observed in the extremities (17.5%), in the cephalic segment (8.4%), chest (5.5%) and the abdomen (2.9%). Victims of Group 1 had significantly higher mean age, AIS in extremities / pelvis, AIS in the thoracic segment and ISS (p <0.05). The group 1 had significantly (p <0.05) higher incidence of tracheal intubation on admission, pneumothorax, hemothorax, rib fractures, chest drainage, spinal trauma, pelvic fractures, complex pelvic fractures and fractures to the upper limbs.CONCLUSION: Victims of fall from height had greater anatomic injury severity, greater frequency and severity of lesions in the thoracic segment and extremities.

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OBJECTIVE:to identify predictors of death in blunt trauma patients sustaining pelvic fractures and, posteriorly, compare them to a previously reported series from the same center.METHOD: Retrospective analysis of trauma registry data, including blunt trauma patients older than 14 y.o. sustaining pelvic fractures admitted from 2008 to 2010. Patients were assigned into group 1 (dead) or 2 (survivors). We used Student's t, qui square and Fisher's tests for statistical analysis, considering p<0.05 as significant. Posteriorly, we compared predictors of death between both periods.RESULTS: Seventy-nine cases were included. Mean RTS, ISS and TRISS were, respectively, 6.44 + 2.22, 28.0 + 15.2 e 0.74 + 0.33. Nineteen patients died (24,0%). Main cause of death was hemorrhage (42,1%). Group 1 was characterized by (p<0.05) lower systolic blood pressure and Glasgow coma scale means on admission, higher heart rate, head AIS, extremity AIS and ISS means, as well as, higher frequency of severe head injuries and complex pelvic fractures. Comparing both periods, we notice that the anatomic and physiologic severity of injury increased (RTS and ISS means). Furthermore, there was a decrease in the impact of associated thoracic and abdominal injuries on the prognosis and an association of lethality with the presence of complex pelvic fractures.CONCLUSION: There were significant changes in the predictors of death between these two periods. The impact of thoracic and abdominal associated injures decreased while the importance of severe retroperitoneal hemorrhage increased. There was also an increase in trauma severity, which accounted for high lethality.

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Tarkastelen tutkielmassani Dan Simmonsin kaksiosaista tieteisfiktioteosta, joka koostuu romaaneista Hyperion ja The Fall of Hyperion. Keskityn teoksissa esiintyvään Shrike-hirviöön, joka edustaa ihmiskunnan pelkäämää potentiaalista konfliktia ihmisten ja koneiden välillä. Pelko ja konflikti ovat keskeisiä teemoja paitsi tieteisfiktiossa, myös hirviöteoksissa yleensä, ja näiden kahden käyttö samassa kertomuksessa luo otolliset edellytykset nyky-yhteiskunnan ahdistusten kuvaamiseen. Hirviöitä ja tieteisfiktiota on tätä nykyä tutkittu melko laajalti, mutta Shrike on aiemmin jäänyt vähälle huomiolle. Lähtökohtaisen teoreettisen viitekehyksen tutkimukselleni ovat luoneet Jeffrey Cohenin Monster Theory: Reading Culture, Stephen Asman On Monsters: An Unnatural History of Our Worst Fears sekä Holly Lynn Baumgartnerin ja Roger Davisin At the Interface: Hosting the Monster. Teoksista kokoamani hirviöteorian kautta tarkastelen sitä, miten Shriken puoliksi orgaaninen ja puoliksi keinotekoinen keho heijastaa niitä romaaneissa esiintyviä osa-alueita, joista tulevaisuudenpelko ja ihmisten ja koneiden väliseen konfliktin uhka koostuu. Koska Shrike on puoliksi orgaaninen ja puoliksi keinotekoinen, se on näiden ominaisuuksien kynnyksellä; tässä risteytyneessä kehossa yhdistyvät molemmat ääripäät, jolloin tämä keho myös symboloi osapuolten välistä konfliktia. Konfliktin lisäksi Shrike ilmentää niitä vastakkaisuuksia, joista ihmisten ja koneiden välisen konfliktin pelko rakentuu: itseyttä ja toiseutta, houkuttelevuutta ja luotaantyöntävyyttä, menneisyyttä ja tulevaisuutta sekä utopiaa ja dystopiaa.

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The interference imposed the by weeds on corn decreases practically all vegetative characteristics. As consequence, the green ear and grain yield are also reduced. Losses due to the fall armyworm (Spodoptera frugiperda) attack can reduce corn grain yield up to 34%. In general, weed and insect control issues are addressed separately in research papers. Nevertheless, interaction between weeds and insects may exist. This study aimed to evaluate green ear and corn grain yield response to weed and fall armyworm control. A completely randomized block design with split-plots and five replicates was adopted. Corn cultivar AG 1051 was grown under weedy conditions or with control by hand hoeings performed at 20 and 40 days after planting. Fall armyworm control (applied to subplots) was performed with sprays of water (control), deltamethrin (5g active ingredient ha-1); neem oil, at 0.5% (diluted in water), and neem leaf extract at 5%. Each product was sprayed three times, at seven-day intervals, starting at the 7th day after planting, using 150 L ha-1 of the tank solution. Dry mass of the above-ground part, internode diameter, leaf length, leaf width, leaf area, green ear yield and grain yield of corn were reduced due to the lack of weed control. Fall armyworm control in the weeded plots did not influence green ear yield and grain yield, except green mass of marketable, husked ears, which was reduced when the caterpillar was not controlled. Without weed control, neem extracts and deltamethrin sprays provided highest yields of number and total weight of green ears with husks, number and weight of marketable ears with husks and number of marketable ears without husks. The best results for husked ear mass and for grain yield were obtained with neem extract and deltamethrin, respectively.

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Litterfall and transfer of nutrients was estimated in two tropical coastal forests of Brazil - the Atlantic and the Restinga Forests at Cardoso Island, São Paulo. Samples were collected monthly, from June 1990 to May 1991, using thirty 0.25 m2 traps. There were significant differences in litter production between the Atlantic Forest (6.3 t.ha-1.year-1) and the Restinga Forest (3.9 t.ha-1.year-1). Litterfall was continuous throughout the year with maximum in the beginning of the rainy season in both sites. The annual return of mineral elements through litter in the Atlantic Forest was (kg.ha-1): 101.8 N, 3.8 P, 20.3 K, 60.0 Ca, 18.0 Mg, and 14.6 S and in the Restinga Forest was: 27.5 N, 1.0 P, 6.5 K, 30.0 Ca, 10.9 Mg, and 6.6 S. The return, although small, is relevant due to the low fertility of the soils in those ecosystems, especially in Restinga. The Restinga Forest seems to be an ecosystem well adapted to oligotrophic conditions, lying among those presenting higher nutrient use efficiency.

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Litter directly and indirectly affects germination and development of seedlings through physical and chemical effects, being an important factor in the determination of plant community. The monthly accumulation of litter was studied from November 1996 to September 1998 and its relation to climatic factors (such as rainfall, photoperiod and temperature). Also the litter effect on the recruitment of seedlings was observed in the Mata de Santa Genebra (22°49'45" S - 47°06'33" W). The correlation between litter accumulation and climatic factors was very weak. Under the canopy, the removal of the litter layer increased seedling emergence. Seedling mortality was very high, even in the rainy season. This can be due possibly by the low light intensity under the canopy.

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Irtokartta

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Lack of the physiological nocturnal fall in blood pressure (BP) has been found in diabetics and it seems to be related to the presence of diabetic complications. The present study examined the changes in the nocturnal BP pattern of 8 normotensive insulin-dependent diabetic adolescents without nephropathy following improvement in glycemic control induced by an 8-day program of adequate diet and exercise. The same number of age- and sex-matched control subjects were studied. During the first and eighth nights of the program, BP was obtained by ambulatory BP monitoring. After a 10-min rest, 3 BP and heart rate (HR) recordings were taken and the mean values were considered to represent their awake values. The monitor was programmed to cuff insufflation every 20 min from 10:00 p.m. to 7:00 a.m. The glycemic control of diabetics improved since glycemia (212.0 ± 91.5 to 140.2 ± 69.1 mg/dl, P<0.03), urine glucose (12.7 ± 11.8 to 8.6 ± 6.4 g/24 h, P = 0.08) and insulin dose (31.1 ± 7.7 to 16.1 ± 9.7 U/day, P<0.01) were reduced on the last day. The mean BP of control subjects markedly decreased during the sleeping hours of night 1 (92.3 ± 6.4 to 78.1 ± 5.0 mmHg, P<0.001) and night 8 (87.3 ± 6.7 to 76.9 ± 3.6 mmHg, P<0.001). Diabetic patients showed a slight decrease in mean BP during the first night. However, the fall in BP during the nocturnal period increased significantly on the eighth night. The average awake-sleep BP variation was significantly higher at the end of the study (4.2 vs 10.3%, P<0.05) and this ratio turned out to be similar to that found in the control group (10.3 vs 16.3%). HR variation also increased on the eighth night in the diabetics. Following the metabolic improvement obtained at the end of the period, the nocturnal BP variation of diabetics was close to the normal pattern. We suggest that amelioration of glycemic control may influence the awake-sleep BP and HR differences. This effect may be due at least in part to an attenuated insulin stimulation of sympathetic activity

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Neonatal handling induces several behavioral and neurochemical alterations in pups, including decreased responses to stress and reduced fear in new environments. However, there are few reports in the literature concerning the behavioral effects of this neonatal intervention on the dams during the postpartum period. Therefore, the aim of the current study was to determine if brief postpartum separation from pups has a persistent impact on the dam's stress response and behavior. Litters were divided into two neonatal groups: 1) non-handled and 2) handled [10 min/day, from postnatal day (PND) 1 to 10]. Weaning occurred at PND 21 when behavioral tasks started to be applied to the dams, including sweet food ingestion (PND 21), forced swimming test (PND 28), and locomotor response to a psychostimulant (PND 28). On postpartum day 40, plasma was collected at baseline for leptin assays and after 1 h of restraint for corticosterone assay. Regarding sweet food consumption, behavior during the forced swimming test or plasma leptin levels did not differ between dams briefly separated and non-separated from their pups during the postpartum period. On the other hand, both increased locomotion in response to diethylpropion and increased corticosterone secretion in response to acute stress were detected in dams briefly separated from their pups during the first 10 postnatal days. Taken together, these findings suggest that brief, repeated separations from the pups during the neonatal period persistently impact the behavior and induce signs of dopaminergic sensitization in the dam.

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This paper shows how rapid privatization and liberalization of Iceland's small local banks around 2000, combined with well-developed crony relations among the elite, enabled a small group of financiers to leverage government-guaranteed deposits into a vast wave of mergers and acquisitions abroad, and redistribute enough of the profits back home to make the economy boom. Negative policy feedback loops were systematically undermined. The incoming left-wing government, with IMF support, has managed to protect the bulk of the population from the worst of the effects.

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Fokuserande händelser är plötsliga, ovanliga och för med sig negativa konsekvenser för ett stort antal människor. Det handlar om det vi i vardagligt tal kallar kriser och katastrofer. En intensiv medierapportering i kombination med oroade medborgare gör att kriser och katastrofer är viktiga samhällspåfrestningar som beslutsfattare måste hantera. Syftet med avhandlingen är att öka förståelsen för hur fokuserande händelser påverkar samhälleliga processer. Avhandlingens två övergripande forskningsfrågor tar fasta på jämförelsen av olika typer av fokuserande händelser. För det första, skillnader i hur naturkatastrofer och katastrofer som tillkommit genom mänskligt handlade påverkar samhället, och för det andra, hur händelser med olika stark fokuseringskraft påverkar samhället. Medborgarreaktioner studeras i en experimentell laboratoriestudie, den mediala rapporteringen analyseras genom kvantitativ innehållsanalys av texter och bilder, och på den parlamentariska arenan analyseras riksdagsdebatten genom kvantitativ innehållsanalys. De temaområden som identifieras i den teoretiska referensramen ligger till grund för analysen och tar fasta på de känslor som händelsen ger upphov till, hur händelsen kontextualiseras (framing), skuldbeläggning samt möjliga lösningar som förs fram. Resultatet från studierna visar att skillnader mellan olika typer av händelser syns tydligast hos medborgare, uttryckt genom starkare emotionella reaktioner för händelser med stark fokusering, och på den mediala arenan, genom mer utrymme för dessa händelser. Då kriser och katastrofer med olika stark fokuseringskraft når riksdagen får de däremot ett relativt likadant mottagande. I jämförelsen mellan naturkatastrofer och människoskapade händelser visar resultaten att naturkatastrofer ofta diskuteras som specifika händelser, medan människoskapade händelser placeras i en bredare samhällelig kontext och diskuteras under längre tid. Avhandlingen bidrar till diskussionen om hur våra känslor och vår kognition samspelar i krissituationer. De omedvetna signaler som vår kropp ger oss gällande hur vi ska reagera på en farlig situation kan påverka om vi är rädda, oroliga eller till och med positivt inställda. I ljuset av de tre studierna är det tydligt att de emotionella reaktionerna minskar ju högre upp i den politiska processen vi kommer. Trots att medborgare och medier reagerar starkt är de emotionella reaktionerna på den politiska arenan relativt milda och skuldbeläggningen näst intill icke-existerande.