Evaluations of land cover risk factors for canine leptospirosis: 94 cases (2002-2009)

Associations of land cover/land use variables and the presence of dogs in urban vs. rural address locations were evaluated retrospectively as potential risk factors for canine leptospirosis in Kansas and Nebraska using Geographic Information Systems (GIS). The sample included 94 dogs positive for leptospirosis predominantly based on a positive polymerase chain reaction test for leptospires in urine, isolation of leptospires on urine culture, a single reciprocal serum titer of 12,800 or greater, or a four-fold rise in reciprocal serum titers over a 2-4 weeks period; and 185 dogs negative for leptospirosis based on a negative polymerase chain reaction test and reciprocal serum titers less than 400. Land cover features from 2001 National Land Cover Dataset and 2001 Kansas Gap Analysis Program datasets around geocoded addresses of case/control locations were extracted using 2500m buffers, and the presence of dogs' address locations within urban vs. rural areas were estimated in GIS. Multivariate logistic models were used to determine the risk of different land cover variables and address locations to dogs. Medium intensity urban areas (OR=1.805, 95% C.I.=1.396, 2.334), urban areas in general (OR=2.021, 95% C.I.=1.360, 3.003), and having urban address locations (OR=3.732, 95% C.I.=1.935, 7.196 entire study region), were significant risk factors for canine leptospirosis. Dogs regardless of age, sex and breed that live in urban areas are at higher risk of leptospirosis and vaccination should be considered.     

Identification of hyperendemic foci of horses with West Nile virus disease in Texas

OBJECTIVE: To determine whether West Nile virus (WNV) disease hyperendemic foci (hot spots) exist within the horse population in Texas and, if detected, to identify the locations. SAMPLE POPULATION: Reports of 1,907 horses with WNV disease in Texas from 2002 to 2004. Procedures: Case data with spatial information from WNV epidemics occurring in 2002 (1,377 horses), 2003 (396 horses), and 2004 (134 horses) were analyzed by use of the spatial scan statistic (Poisson model) and kriging of empirical Bayes smoothed county attack rates to determine locations of horses with WNV disease in which affected horses were consistently (in each of the 3 study years) clustered (hyperendemic foci, or hot spots). RESULTS: 2 WNV hot spots in Texas, an area in northwestern Texas and an area in eastern Texas, were identified with the scan statistic. Risk maps of the WNV epidemics were qualitatively consistent with the hot spots identified. Conclusions and CLINICAL RELEVANCE: WNV hot spots existed within the horse population in Texas (2002 to 2004). Knowledge of disease hot spots allows disease control and prevention programs to be made more efficient through targeted surveillance and education.     

Fatal dog attacks in Canada, 1990-2007

In Canada, public debates on dog attacks are dominated by studies from the United States. An electronic search of media reports in the Canadian Newsstand database, for the years 1990 to 2007, identified 28 fatalities from dog-bite injuries. Predominant factors in this case series were owned, known dogs; residential location; children's unsupervised access to area with dogs; and rural/remote areas, including aboriginal reserves in the prairies. A higher proportion of sled dogs and, possibly, mixed-breed dogs in Canada than in the United States caused fatalities, as did multiple dogs rather than single dogs. Free-roaming dog packs, reported only from rural communities, caused most on-reserve fatalities. Future studies are needed to assess if this rural/urban divide is observed in nonfatal attacks and if the breeds that bite in Canada are different from the breeds that killed. Breed representation in this paper and, perhaps, multiple-dog overrepresentation should be understood in the context of the overall Canadian dog population.     

Real-time, volatile-detection-assisted control for microwave drying

A real-time, volatile-detection-assisted control system was designed for microwave drying. Detected volatile signals were integrated to a fuzzy logic algorithm to determine the drying temperature. A phase controller was used to automatically and continuously adjust the microwave power. A data acquisition unit with developed program was employed to integrate the entire control. Carrot samples were used in system tests. The results showed that the designed system could successfully achieve the desired temperature, power, and volatiles control and lead to acceptable product's quality.     

Surface drainage nitrate loading estimate from agriculture fields and its relationship with landscape metrics in Tajan watershed

Pasture, forest, and farmland are the dominant land covers in the Tajan River watershed and this landscape status has a direct connection with nitrate pollution. Understanding the correlations between landscape variables and nitrate pollutant is a priority in order to assess pollutants loading and predicting the impact on surface water quality. The soil and water assessment tool was used to simulate nitrate loads in different land cover types in different years. The landscape pattern was calculated by FRAGSTATS. The contributing share of each land use/land cover shows nitrate pollutant produced by grassland (5.7%) and forest (29%) are less than those produced by agricultural land (64.2%). Agricultural land was identified as the main source of nitrate pollution. Paddy fields and orchards had the most intensive soluble nitrate loss especially in spring and summer. Statistical analysis indicated that nitrate was positively associated with patch density, edge density, patch number, total edge, effective mesh size, largest patch index, and landscape shape index (p ≤ 0.01). We then analyzed how nitrate was related to landscape attributes in six different sites. Also the regression analysis results suggested that landscape metrics could account for more than 94% of the variance of nitrate in the whole catchment. The regression models confirmed the great importance of the agriculture metrics and forest metric in predicting nitrate in watershed. Defining the generation and extent of pollution in this particular watershed which discharges into the Caspian Sea can constitute an important step toward protecting this ecosystem.     

‘Damsel in distress’‐ The tale of Miss Kerala,Puntius denisonii (Day), an endemic and endangered cyprinid of the Western Ghats biodiversity hotspot (South India)

• 1. Denison's Barb, Puntius denisonii (Day) is an endemic and endangered cyprinid fish of the Western Ghats biodiversity hotspot in peninsular India, which is the focus of an organized yet undocumented fishery targeting juveniles for the international aquarium trade.
• 2. Research on P. denisonii has been very limited and there has been no systematic effort to assess and monitor their abundance, distribution and populations.
• 3. Anecdotal and circumstantial evidence indicates a highly restricted distribution, low abundance, declining populations, low catch per unit effort and increasing market prices, providing evidence of an impending conservation crisis and the need for urgent management of wild stocks.
• 4. This paper reviews current knowledge, provides results from the authors' field study and suggests priorities for conservation and management actions for P. denisonii in the streams of Kerala.

Copyright © 2008 John Wiley & Sons, Ltd.     

Biological control of weeds using plant pathogens: accomplishments and limitations

The science and technology of weed control by using plant pathogens gained attention and momentum in the 1970s when some century-old concepts in weed biocontrol and plant disease epidemiology were successfully put to test and a few economically important weeds were controlled by two different strategies. Since then, researchers in different parts of the world have critically examined and tried to apply these strategies with the hope of solving some of the most intractable weed problems. Depending on one"s point of view, this biological control approach has been quite successful or wrought with limitations. In this paper, we describe some of the accomplishments as well as the limitations in this field.     

Solar neutrinos--from puzzle to paradox

The solar neutrino puzzle is deepening into a paradox that refutes the basic logic of the reaction chain that powers the sun by the fusion of protons into heavy elements. Experiments now reveal a serious anomaly in the relative neutrino fluxes from the different steps in the chain. Neutrinos from boron-8 at the end of the chain are seen but hardly any are seen from beryllium-7, without which the observed boron-8 cannot be made. The only apparent way to avoid a paradoxical "missing link" in the sun's energy chain is a nonzero neutrino mass, an idea that can be tested in future experiments.