Optimal progressive taxation in a model with endogenous skill supply

No abstract available

Some results on contractive mappings as related to pattern recognition

Several of the techniques used in pattern recognition are reformulated as the problem of determining fixed points of a function. If x sub 0 is a fixed point of f and if f is contractive at x sub 0, then, for any y belonging to a sufficiently small neighborhood of x sub 0 the orbit of y will converge to x sub 0. Several general results regarding contractive mappings are developed with emphasis on functions

Micro-geographic risk factors for malarial infection.

BACKGROUND: Knowledge of geography is integral to the study of insect-borne infectious disease such as malaria. This study was designed to evaluate whether geographic parameters are associated with malarial infection in the East Sepik province of Papua New Guinea (PNG), a remote area where malaria is a major cause of morbidity and mortality. METHODS: A global positioning system (GPS) unit was used at each village to collect elevation, latitude and longitude data. Concurrently, a sketch map of each village was generated and the villages were sub-divided into regions of roughly equal populations. Blood samples were taken from subjects in each region using filter paper collection. The samples were later processed using nested PCR for qualitative determination of malarial infection. The area was mapped using the GPS-information and overlaid with prevalence data. Data tables were examined using traditional chi square statistical techniques. A logistic regression analysis was then used to determine the significance of geographic risk factors including, elevation, distance from administrative centre and village of residence. RESULTS: Three hundred and thirty-two samples were included (24% of the total estimated population). Ninety-six were positive, yielding a prevalence of 29%. Chi square testing within each village found a non-random distribution of cases across sub-regions (p < 0.05). Multivariate logistic regression techniques suggested malarial infection changed with elevation (OR = 0.64 per 10 m, p < 0.05) and distance from administrative centre (OR = 1.3 per 100 m, p < 0.05). CONCLUSION: These results suggest that malarial infection is significantly and independently associated with lower elevation and greater distance from administrative centre in a rural area in PNG. This type of analysis can provide information that may be used to target specific areas in developing countries for malaria prevention and treatment

A Classical Molecular Dynamics Study on the Effect of Si/Al Ratio and Silanol Nest Defects on Water Diffusion in Zeolite HY

The diffusion of water confined in zeolite HY has been studied using classical molecular dynamics at 300 K to probe the effects of water loading, Si/Al ratio, and silanol nest defect presence on the behavior of water confined in Brønsted acidic faujasite (FAU) zeolites. Water loading, ranging from 5 to 33 wt %, is shown to have a significant effect on diffusivity, showing an increase by a factor of ∼7 over the loading range, toward a maximum diffusivity. Upon probing the effect of Si/Al ratio (in a range of Si/Al = 5 to fully siliceous), water diffusivity tends to decrease with the concentration of Brønsted acid sites which show strong interactions with the water molecules and thus hinder molecular mobility. The average residence time of water adsorbed to each Brønsted acid site also decreased with both water loading and Si/Al ratio. Water diffusivity shows the highest dependency on Si/Al ratio at 18 wt % loading, as a lack of total mobility in the systems at the lowest loadings is observed (due to significant populations of water molecules being immobilized via interaction with the framework and Brønsted acid sites), and less of a dependence is observed at the highest loadings due to the prevalence of sorbate-sorbate interactions. Notably, silanol nest presence (at a concentration of 1 per unit cell) had no significant effect on the diffusivity of water in HY at any water loading or Si/Al ratio. Reasons considered for this lack of influence include silanol geometry and flexibility at ambient temperature and potentially a lower effective charge density of the defect site.</p

Malaria in the southern highlands of Tanzania: a review of hospital records

Outpatient attendance and inpatient admission records were examined to assess malaria situation in ten hospitals in Mbeya and Iringa Regions in southern highlands of Tanzania for a period of fifteen years from 1986-2000. Generally, records were deficient, some hospitals with entire annual records missing for one or several years. However, malaria maintained a high profile as the leading cause of admissions and deaths among hospital attendees. Of the ten hospitals, seven recorded malaria as the leading cause of admissions for at least ten years; in three of these, it was also the top ranking cause of child death. Although the respective magnitude of malaria morbidity and mortality burdens was not directly correlated with altitude (P>0.5), three hospitals (Uwemba, Bulongwa and Ikonda) at above 2,000m, had relatively lower malaria morbidity and mortality burden compared to three worst affected facilities (Ilembula, Chimala and Mbozi) in the lower range of altitude, located in the flat plains. In conclusion, malaria is the major public health problem in the highlands districts of Mbeya and Iringa Regions in Tanzania that need the attention of health authorities and immediate intervention. However, more research is required to establish the true picture of the problem among the communities. Keywords: malaria, hospital, surveillance, highlands, Tanzania Tanzania Health Research Bulletin Vol. 7(3) 2005: 125-13

Optimal progressive taxation in a model with endogenous skill supply

No abstract available

Complete mitochondrial genome of the speckled dace \u3ci\u3eRhinichthys osculus\u3c/i\u3e, a widely distributed cyprinid minnow of western North America

The speckled dace Rhinichthys osculus (order Cypriniformes), also known as the carpita pinta, is a small cyprinid minnow native to western North America. Here, we report the sequencing of the full mitochondrial genome (mitogenome) of R. osculus from a male fish collected from the Amargosa River Canyon in eastern California, USA. The assembled mitogenome is 16 658 base pair (bp) nucleotides, and encodes 13 protein-coding genes, and includes both a 12S and a 16S rRNA, 22 tRNAs, and a 985 bp D-loop control region. Mitogenome synteny reflects that of other Ostariophysian fishes with the majority of genes and RNAs encoded on the heavy strand (H-strand) except nd6, tRNA-Gln, tRNA-Ala, tRNA-Asn, tRNA-Cys, tRNA-Tyr, tRNA-Ser, tRNA-Glu, and tRNA-Pro. The availability of this R. osculus mitochondrial genome – the first complete mitogenome within the lineage of Rhinichthys riffle daces – provides a foundation for resolving evolutionary relationships among morphologically differentiated populations of R. osculus