Patterns and Rates of Land Use Land Cover Change: A Case Study of Ambos Nogales (Arizona and Sonora), 1985-2004

Abstract The continued expansion of the paired U.S.–Mexican border cities of Ambos Nogales presents many environmental management and urban planning challenges. This study focuses on a comparative study of spatial patterns and rates of land-use and land-cover change, in relation to land degradation, deforestation, and urban growth over different time periods. Based on historical data the study suggests that both cities have experi- enced high land degradation; however, land on the Arizona-side has been more stable and less degraded. However, there were more severely degraded areas found in Nogales, Arizona, than in Nogales, Sonora. The delineation of land use change and the severity of land degradation provide important information to planners about areas that should be targeted for development and other areas that require restoration to natural settings. Keywords: Nogales, land use land cover, urban growth, land degradation Resumen La expansión continua de las ciudades gemelas de Ambos Nogales (USA-Mexico) presenta muchos desafíos de planificación urbana y manejo ambiental. Este estudio se concentra en un análisis comparativo de los patrones espaciales y velocidad de cambios de uso del suelo con relación a la degradación del terreno, deforestación, y crecimiento urbano durante distintos períodos de tiempo. Basado en datos históricos el estudio sugiere que ambas ciudades han experimentado alta degradación de tierra, pero la tierra en el lado de Arizona ha sido más estable y menos degradada. Sin embargo, en Nogales Arizona, habían áreas severamente más degradadas que en Nogales, Sonora. Palabras clave: Nogales, crecimiento urbano, uso de suelo, degradación de tierra

Prevalence of multidrug resistance Campylobacter jejuni and Campylobacter coli in chickens slaughtered in selected markets, Malaysia

The objectives of this study were to determine the occurrence of Campylobacter spp. in live chickens sold at wet markets in Selangor, Malaysia and the multidrug resistance (MDR) profiles of the isolates. Cloacal swabs were taken from the chickens before slaughter and their caecal mucosae were swabbed after slaughter. Of the 90 chickens examined, 68 (75.6%) were positive for Campylobacter. Campylobacter were recovered from caecal swabs (53/90) and cloacal swabs (34/90) and Campylobacter coli (46 isolates) were identified slightly more than Campylobacter jejuni (41 isolates), but these differences were not significant (p<0.05). The most frequently observed resistance was to cephalothin (95.5%), followed by tetracycline (80.8%), erythromycin (51.4%), enrofloxacin (42.4%) and gentamicin (24.4%). Multidrug resistance (resistant to four or more antibiotics) was detected in 35.3% isolates. Campylobacter jejuni showed nine resistance profiles and the most common was to gentamicin-eryhtromycin-enrofloxacin-cephalothin-tetracycline (32.4%) combination while C. coli showed six profiles, with cephalothin-tetracycline (32.2%) combination being most common