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31.
The nematode Spirocerca lupi is primarily a parasite of dogs, which causes typical lesions of esophageal nodular granulomas, aortic aneurysms and spondylitis. In order to evaluate the therapeutic effect of doramectin on experimental canine spirocercosis, seven beagle dogs experimentally infected with 40 infectious S. lupi larvae (L(3)) were treated with doramectin. Treatment was commenced following endoscopic visualization of esophageal granulomas, and typical S. lupi eggs were detected in the feces. The treatment protocol included six treatments of doramectin (400 microg/kg subcutaneously) at 2 weeks intervals, followed by monthly injections until the disappearance of the esophageal granulomas or the end of the study (768 days post-inoculation).Eggs could not be found on fecal examinations 3-10 days after the first or second doramectin treatment. In addition, a gradual decrease in size of granulomas was noticed in all seven dogs during the course of the study. Esophageal granulomas had completely resolved in six of the seven dogs between day 35 and day 544 post-initial doramectin treatment, by day 35 in one dog (after three treatments), by day 43 in two dogs (after four treatments), by day 98 in one dog (after seven treatments), by day 460 in one dog (after 18 treatments) and by day 544 in another dog (after 21 treatments). In one dog, remnants of S. lupi granulomas could still be seen 544 days post-initiation of treatment with doramectin. Multiple subcutaneous injections of doramectin (400 microg/kg) were shown to be effective and safe in the treatment of canine spirocercosis.  相似文献   
32.

Context

Wildfires destroy thousands of buildings every year in the wildland urban interface. However, fire typically only destroys a fraction of the buildings within a given fire perimeter, suggesting more could be done to mitigate risk if we understood how to configure residential landscapes so that both people and buildings could survive fire.

Objectives

Our goal was to understand the relative importance of vegetation, topography and spatial arrangement of buildings on building loss, within the fire’s landscape context.

Methods

We analyzed two fires: one in San Diego, CA and another in Boulder, CO. We analyzed Google Earth historical imagery to digitize buildings exposed to the fires, a geographic information system to measure some of the explanatory variables, and FRAGSTATS to quantify landscape metrics. Using logistic regression we conducted an exhaustive model search to select the best models.

Results

The type of variables that were important varied across communities. We found complex spatial effects and no single model explained building loss everywhere, but topography and the spatial arrangement of buildings explained most of the variability in building losses. Vegetation connectivity was more important than vegetation type.

Conclusions

Location and spatial arrangement of buildings affect which buildings burn in a wildfire, which is important for urban planning, building siting, landscape design of future development, and to target fire prevention, fuel reduction, and homeowner education efforts in existing communities. Landscape context of buildings and communities is an important aspect of building loss, and if taken into consideration, could help communities adapt to fire.
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A priority list of 323 plant species was created through a consultative process for ex situ conservation in the recently inaugurated Israel Plant Gene Bank (IGB). The IGB is set up to preserve plant genetic resources and the endangered genetic variability of the Israeli flora. Upon its inauguration, we consulted with the country’s leading plant breeders and botanists in an attempt to create a list of the most important plant species to be included in the initial collections. The list includes crop wild relatives (CWRs), selected according to their contribution to humans: edible plants (grains, vegetables, oil); forage plants; species with potential industrial and biotechnological applications (e.g. spices, medicinal plants, aromatic plants, fibers, dyes), and species with horticultural and forestry potential. We further ranked the species on the basis of assessed values for each of seven characteristics: distribution range in the country; abundance; rarity of the growing habitats; endemism; red number index—representing imminent threat of extinction; availability of samples in Israeli collections, and genetic relationship to cultivated crops. The sum of the assessed values for these seven characteristics was used to group the species on the list into four main prioritized-collection schemes. Statistical analysis indicated that all attributes had similar influence on the collecting prioritization scheme. In general, rare species with low abundance in their growing habitats were ranked in the highest priority group, while highly distributed species were sorted together into a lower priority group. The prioritization scheme will be used to optimize the collection in the IGB with the aim of establishing its collecting activities.  相似文献   
35.
Serum concentrations of leptin and insulin were compared between gender-matched hypothyroid (n=25) and healthy (n=25) client-owned dogs within comparable age and body condition score (BCS) ranges. Fasted blood samples were collected from each dog and analysed for glucose, cholesterol, triglyceride, leptin and insulin concentrations. Leptin and insulin concentrations were significantly higher in the hypothyroid compared to normal dogs (P=0.006 and P=0.001, respectively) following adjustment for potential confounders. A nearly significant (P=0.051) interaction with BCS was found in the association between hypothyroidism and leptin. Leptin concentrations were significantly higher in hypothyroid dogs compared to normal dogs, in separate analyses for BCS 6 (P=0.036) and 7 (P=0.049). There was no significant difference in glucose concentration between the hypothyroid and normal groups (P=0.84) following adjustment for BCS. This study showed that canine hypothyroidism is associated with increased serum leptin and insulin concentrations, neither of which may be attributed to obesity alone.  相似文献   
36.
The EU project SAFIR aimed to help farmers solve problems related to the use of low quality water for irrigation in a context of increasing scarcity of conventional freshwater resources. New decentralised water treatment devices (prototypes) were developed to allow a safe direct or indirect reuse of wastewater produced by small communities/industries or the use of polluted surface water. Water treatment technologies were coupled with irrigation strategies and technologies to obtain a flexible, easy to use, integrated management of the system. The challenge is to apply new strategies and technologies which allow using the lowest irrigation water quality without harming food safety or yield and fruit or derivatives quality. This study presents the results of prototype testing of a small-scale compact pressurized membrane bioreactor and of a modular field treatment system including commercial gravel filters and heavy-metal specific adsorption materials. Decentralised compact pressurised membrane biobooster (MBR), was able to remove up to 99.99% of the inlet Escherichia coli and 98.52% of total coliforms. E. coli was completely removed from irrigation water in 53% of the samples by the last MBR prototype version. In 2008, 100% of samples fulfilled WHO standards (1989) and Global Gap requirement for faecal contamination. MBR removed from inlet flow in the average 82% of arsenic, 82% of cadmium, 97% of chromium, 93% of copper and 99% of lead. Boron and manganese were not removed from permeate. The field treatment system (FTS) proved to be effective against faecal contamination when applied with its complete set up including UV treatment. The sole gravel filter and heavy metal removal device (HMR) cannot provide sufficient and steadily treatment for microbial contamination. Nevertheless, gravel filter can remove up to 60% of E. coli but the removal process was not stable nor predictable. FTS removed 76% of arsenic, 80% of cadmium and copper, 88% of chromium and lead, and up to 97% of zinc. Like the MBR, boron and manganese were not removed from the irrigation water. Gravel filter directly fed with secondary treated wastewater was found able to remove 41% of arsenic, 36% of cadmium and lead, 48% of chromium and 46% of copper. The residual heavy metals concentration after the gravel filter was further reduced by the HMR: 35% for arsenic, 22% for cadmium, 25% for chromium, 33% for copper and 53% for lead.  相似文献   
37.
Close-in giant planets (e.g., "hot Jupiters") are thought to form far from their host stars and migrate inward, through the terrestrial planet zone, via torques with a massive gaseous disk. Here we simulate terrestrial planet growth during and after giant planet migration. Several-Earth-mass planets also form interior to the migrating jovian planet, analogous to recently discovered "hot Earths." Very-water-rich, Earth-mass planets form from surviving material outside the giant planet's orbit, often in the habitable zone and with low orbital eccentricities. More than a third of the known systems of giant planets may harbor Earth-like planets.  相似文献   
38.
39.
Avi Eitam 《Phytoparasitica》2001,29(5):405-412
Parasierola swirskiana Argaman (Hymenoptera: Bethylidae) is a parasitoid of the mothBatrachedra amydraula Meyrick, a pest of unripe fruits of the date palm,Phoenix dactylifera L. The parasitoid is most commonly found in the field on second-generation host ,larvae. Its biological characteristics were studied in the laboratory. Adult longevity averaged 34.9 and 20.5 days for females and males, respectively. Clutch size ranged between 1 and 13 eggs per host, and was positively correlated with host weight. Females laid an average of 60.4 eggs on 11.6 hosts, with a maximum of 152 eggs on 29 hosts in 53 days. Parasitoids were observed standing motionless upon 52% of the paralyzed hosts, and active brood defense was occasionally observed. Immature development is described. Total development time from egg to adult averaged 13.6 days at 26 ± 2°C and 30-50% r.h. The potential for utilizingP. swirskiana for biological control ofB. amydraula is discussed.  相似文献   
40.
The permeability of plastic films to the fumigant methyl bromide (MB) was measured by two different methods, in order to facilitate the selection of films which are impermeable to the gas. Polyethylene-based films are highly permeable to MB, as evidenced by both methods. In contrast, multilayer coextruded films which have a layer of barrier material such as polyamide (PA) or ethylene-vinyl alcohol copolymer (EVOH) were significantly less permeable to MB, as reflected by the parameters permeability rate, time to 90% concentration (TC90, by the diffusion method) and lag-time values (by the variable-volume method). A significant correlation was found between the permeability rate assessed by the diffusion method and that obtained with the variable-volume method. Permeability of all films increased with temperature as evidenced by all tested parameters. This increase was more pronounced with polyethylene films, the permeabilities of which increased five- to six-fold when the temperature was increased from 20°C to 60°C. The effect of temperature on barrier-film permeability was less significant. Permeability of films to MB was affected by additional factors such as additives, the length of the monomer side-chain, and the thickness and density of polyethylene films. © 1998 SCI  相似文献   
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