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41.
Moqanaki Ehsan M. Milleret Cyril Tourani Mahdieh Dupont Pierre Bischof Richard 《Landscape Ecology》2021,36(10):2879-2895
Landscape Ecology - Spatial capture-recapture (SCR) models are increasingly popular for analyzing wildlife monitoring data. SCR can account for spatial heterogeneity in detection that arises from... 相似文献
42.
Rell L. Parker John Du Richard L. Shinn Adam G. Drury FangChi Hsu John L. Roberston Thomas E. Cecere Avril U. Arendse John H. Rossmeisl 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2022,36(2):694
BackgroundSeizures in the early postoperative period after intracranial surgery may affect outcome in dogs.ObjectivesTo determine the incidence of early postoperative seizures (EPS) in dogs with brain tumors, identify specific risk factors for EPS, and determine if EPS affects outcome.AnimalsEighty‐eight dogs that underwent 125 intracranial surgeries for diagnosis and treatment of rostrotentorial brain tumors.MethodsRetrospective cohort study. All patients with a diagnosis of rostrotentorial brain tumor from 2006 to 2020 were included. Early postoperative seizures were diagnosed by observation of seizure activity within 14 days of neurosurgery. Previously diagnosed structural epilepsy, perioperative anticonvulsant drug (ACD) use, magnetic resonance imaging (MRI), and tumor characteristics were evaluated. Outcome measures included neurologic and nonneurologic complications, duration of hospitalization, and survival to discharge.ResultsDogs with rostrotentorial brain tumors had EPS after 16/125 (12.8%) neurosurgical procedures (95% confidence interval [CI], 7%‐19%). Presence of previous structural epilepsy was not associated with EPS risk (P = 1). Perioperative ACD use also was not associated with EPS (P = .06). Dogs with EPS had longer hospitalization (P < .001), were more likely to have neurologic complications postsurgery (P = .01), and were less likely to survive to discharge (P = .01).Conclusions and Clinical ImportanceIt is difficult to predict which dogs are at risk of EPS because the presence of previous structural epilepsy and the use of perioperative ACDs was not associated with EPS. However, seizures in the early postoperative period are clinically important because affected dogs had prolonged hospitalization, more neurologic complications, and decreased short‐term survival. 相似文献
43.
过去人们常认为,由于刚出壳雏鸡的免疫系统尚未发育成熟,同时肠道内缺乏有益的微生物,因而处于高度的敏感期,此时接种沙门氏菌苗产生的保护作用很有限。然而,最新的研究表明,在这些敏感期接种疫苗,可诱发产生保护作用。 相似文献
44.
Timothy Beach Sheryl Luzzadder-Beach Richard Terry Nicholas Dunning Stephen Houston Thomas Garrison 《CATENA》2011
This article provides new data and synthesizes earlier findings on the carbon isotope ratios of the humin part of soil organic matter from a range of sites in the central Maya Lowlands. Changes down the soil profile in carbon isotope ratios can provide an important line of evidence for vegetation change and erosion over time, especially in well dated aggrading profiles. Research thus far has provided substantial evidence for significant inputs from C4 vegetation in buried layers from the Ancient Maya periods in depositional soils but equivocal evidence from sloping soils. We present new findings from soil profiles through ancient Maya wetland fields, upland karst wetlands, ancient Maya aguadas (reservoirs), and ancient Maya terraces. Most of the profiles exhibited δ13C enrichment greater than the 2.5–3‰ typical from bacterial fractionation. Seven of nine ancient Maya wetland profiles showed δ13C enrichment ranging from 4.25 to 8.56‰ in ancient Maya-dated sediments that also contained phytolith and pollen evidence of grass (C4 species) dominance. Upland karst sinks and ancient reservoirs produced more modest results for δ13C enrichment. These seasonal wetland profiles exhibited δ13C enrichment ranging from 1 to 7.3‰ from the surface to ancient Maya-period sediments. Agricultural terraces produced mixed results, with two terraces having substantial δ13C enrichment of 5.34 and 5.66‰ and two producing only equivocal results of 1.88 and 3.03‰ from modern topsoils to Maya Classic-period buried soils. Altogether, these findings indicate that C4 plants made up c. 25% of the vegetation at our sites in the Maya Classic period and only a few percent today. These findings advance the small corpus of studies from ancient terraces, karst sinks, and ancient wetland fields by demonstrating substantial δ13C and thus C4 plant enrichment in soil profile sections dated to ancient Maya times. These studies are also providing a new line of evidence about local and regional soil and ecological change in this region of widespread environmental change in the Late Holocene. 相似文献
45.
Manufactured soil for landscaping purposes was produced by composting for 6 weeks (1) municipal green waste alone, (2) green
waste amended with 25% v/v poultry manure, or (3) green waste immersed in, and then removed from, a mixture of liquid grease trap waste/septage. Composting
temperatures increased most rapidly and reached highest values (78oC) in the grease trap/septage-amended green waste. In comparison
with green waste alone, addition of poultry manure prolonged the period of elevated temperatures and increased the maximum
temperature attained from 52oC to 61oC. Following composting, each of the materials was split into (1) 100% compost, (2) 80%
compost plus 20% v/v soil, and (3) 70% compost plus 20% soil plus 10% coal fly ash. Addition of poultry manure or grease trap/septage to green
waste prior to composting increased bulk density and reduced total porosity of the composted product. Addition of soil, or
soil and ash, to composts increased bulk density, reduced total porosity, decreased percentage macropores, and increased percentage
mesopores and available water-holding capacity. Bicarbonate-extractable P, exchangeable NH4+ and NO3−, electrical conductivity (EC), soluble C, soluble C as a percentage of organic C, basal respiration, and metabolic quotient
were all markedly greater in the grease trap/septage-amended than poultry manure-amended or green waste alone treatments.
Values for extractable P and EC were considered large enough to be damaging to plant growth and germination index (GI) of
watercress was less than 60% for all grease trap/septage composts. Extractable P and EC were also high, and GI was <100%,
in the green waste alone and poultry manure-amended green waste alone treatments. Addition of soil or soil and ash to these
composts resulted in GI values >100%. 相似文献
46.
An understanding of the effects of salinity and sodicity on soil carbon (C) stocks and fluxes is critical in environmental
management, as the areal extents of salinity and sodicity are predicted to increase. The effects of salinity and sodicity
on the soil microbial biomass (SMB) and soil respiration were assessed over 12weeks under controlled conditions by subjecting
disturbed soil samples from a vegetated soil profile to leaching with one of six salt solutions; a combination of low-salinity
(0.5dSm−1), mid-salinity (10dSm−1), or high-salinity (30dSm−1), with either low-sodicity (sodium adsorption ratio, SAR, 1), or high-sodicity (SAR 30) to give six treatments: control (low-salinity
low-sodicity); low-salinity high-sodicity; mid-salinity low-sodicity; mid-salinity high-sodicity; high-salinity low-sodicity;
and high-salinity high-sodicity. Soil respiration rate was highest (56–80mg CO2-C kg−1 soil) in the low-salinity treatments and lowest (1–5mg CO2-C kg−1 soil) in the mid-salinity treatments, while the SMB was highest in the high-salinity treatments (459–565mg kg−1 soil) and lowest in the low-salinity treatments (158–172mg kg−1 soil). This was attributed to increased substrate availability with high salt concentrations through either increased dispersion
of soil aggregates or dissolution or hydrolysis of soil organic matter, which may offset some of the stresses placed on the
microbial population from high salt concentrations. The apparent disparity in trends in respiration and the SMB may be due
to an induced shift in the microbial population, from one dominated by more active microorganisms to one dominated by less
active microorganisms. 相似文献
47.
The compostable biopolymer, poly(lactic) acid (PLA), is increasingly being used as an alternative to conventional plastics for short shelf-life products, disposable bags and packaging, and in agriculture. Despite the increase in the amount of PLA entering composting systems, few studies have examined the impact of PLA degradation on the compost microbial community. Thermophilic fungi play an import role in the composting process as they secrete hydrolytic enzymes capable of breaking down an array of complex natural polymers. In this study, the impact of PLA hydrolysis on the compost fungal community was examined by terminal restriction fragment length polymorphism and 454 sequencing. At 25°C, the effect of PLA on the surrounding compost community was relatively small and no physical changes were observed to the PLA films. However, when incubated at 50°C, where physical disintegration of PLA was occurring, a clear divergence between the compost populations in the presence and absence of PLA was evident after 2 months but became closer to the population in the absence of PLA after 4 months indicating that, after causing an initial perturbation after 2 months, the population began to return to that seen in the absence of PLA. The only exception was in the population containing 50% (w/w) PLA film, which remained divergent after 4 months and was associated with a marked acidification of the compost. Thus, 454-pyrosequencing revealed that the presence of PLA caused a strong selection for a Thermomyces sp. that was present only at low abundance in the absence of PLA. 相似文献
48.
Nancy P. Chaves Luis E. Pocasangre Fritz Elango Franklin E. Rosales Richard Sikora 《Scientia Horticulturae》2009,122(3):472-478
Eight endophytic fungal and bacterial isolates with antagonistic activity against Radopholus similis were evaluated in vivo for their individual and combined effects on biocontrol of R. similis and on the growth of “Grand Naine” cultivar banana plantlets in the greenhouse. Penetration efficiency (PE) of R. similis was between 3 and 21% in 29 biological agents (BAs) treatments, less than the 29% of the nematode-alone control (p ≤ 0.0001); 24 of the BAs treatments did not differ from the PE of 5% for a nematicide control. Twenty nine BAs treatments exhibited antagonistic activity against nematodes which reduced final population levels between 18 and 93%, relative to those on nematode-alone control plants (p ≤ 0.0001), and 14 BAs treatments were statistically similar to the nematicide treatment (88% reduction). Twenty four BAs treatments had increments of plant root biomass ranging from 20 to 58%, greater than the control plants; 37% of the treatments with single and combined BAs inoculations had root length increments ranging from 29 to 54% compared with control and chemical treatment. The nematicide, Terbufos 10GR, did not affect plant growth. 相似文献
49.
Antoine LF Gady Freddy WK Hermans Marion HBJ Van de Wal Eibertus N van Loo Richard GF Visser Christian WB Bachem 《Plant methods》2009,5(1):13-14
Background
The establishment of mutant populations together with the strategies for targeted mutation detection has been applied successfully to a large number of organisms including many species in the plant kingdom. Considerable efforts have been invested into research on tomato as a model for berry-fruit plants. With the progress of the tomato sequencing project, reverse genetics becomes an obvious and achievable goal. 相似文献50.