Alzheimer's disease,neuropeptides, neuropeptidase,and amyloid-beta peptide metabolism

Amyloid-beta peptide (Abeta), the pathogenic agent of Alzheimer's disease (AD), is a physiological metabolite in the brain. We have focused our attention and effort on elucidating the unresolved aspect of Abeta metabolism: proteolytic degradation. Among a number of Abeta-degrading enzyme candidates, we used a novel in vivo paradigm to identify a member of the neutral endopeptidase family, neprilysin, as the major Abeta catabolic enzyme. Neprilysin deficiency results in defects in the metabolism of endogenous Abeta 40 and 42 in a gene dose-dependent manner. Our observations suggest that even partial down-regulation of neprilysin activity, which could be caused by aging, can contribute to AD development by promoting Abeta accumulation. Moreover, we discuss the fact that an aging-dependent decline of neprilysin activity, which leads to elevation of Abeta concentrations in the brain, is a natural process that precedes AD pathology. In this Perspective, we hypothesize that neprilysin down-regulation has a role in sporadic AD (SAD) pathogenesis, and we propose that this knowledge be used for developing preventive and therapeutic strategies through use of a G protein-coupled receptor (GPCR).     

Predicting Presence and Level of Nonresident Fathers' Involvement in Infants' Lives: Mothers' Perspective

A nonresident father's involvement can be divided into two components: presence (if a father is involved in his child's life) and level (how much he is involved). Guided by role saliency theory, this study simultaneously examined predictors of these two components. Data were drawn from 1,215 mothers of the Fragile Families and Child Wellbeing Study. Zero-inflated negative binomial regression models revealed that the coparental relationship had different influences on the presence and level of father involvement. Although relationship status, quality, and conflict influenced presence of father's involvement, parents' positive relationship was the major factor that predicted level of involvement.     

Remittances,growth and poverty: New evidence from Asian countries

The present study re-examines the effects of remittances on growth of GDP per capita using annual panel data for 24 Asia and Pacific countries. The results generally confirm that remittance flows have been beneficial to economic growth. However, our analysis also shows that the volatility of capital inflows such as remittances and FDI is harmful to economic growth. This means that, while remittances contribute to better economic performance, they are also a source of output shocks. Finally, remittances contribute to poverty reduction – especially through their direct effects. Migration and remittances are thus potentially a valuable complement to broad-based development efforts.     

ATTRIBUTION ERROR IN ECONOMIC VOTING: EVIDENCE FROM TRADE SHOCKS

This article exploits the international transmission of business cycles to examine the prevalence of attribution error in economic voting in a large panel of countries from 1990 to 2009. We find that voters, on average, exhibit a strong tendency to oust the incumbent governments during an economic downturn, regardless of whether the recession is home‐grown or merely imported from trading partners. However, we find important heterogeneity in the extent of attribution error. A split sample analysis shows that countries with more experienced voters, more educated voters, and possibly more informed voters—all conditions that have been shown to mitigate other voter agency problems—do better in distinguishing imported from domestic growth. (JEL E3, E6)     

A new method to control houseflies,Musca domestica, at waste disposal sites

Summary Investigation was carried out from 1976 to 1979 to establish a new control system against the houseflies,Musca domestica, at a sea-filling waste disposal site in Osaka Bay, Japan. Field surveys showed that the garbage was favorble for the fly breeding for 20–30 days after being disposed, while the sewage sludge and the ash from incinerated refuse were unfavorable. Comparing the fly density at the site to the reported cases of the public complaints in the urban area near to the site, a complaint threshold density of the flies at the site was estimated. Then, a control threshold density was assumed from the complaint threshold density and the reproductive rate of the housefly population. Several insecticides, as well as a surface active agent, polyoxyethylene lauryl ether (PEL), were found effective for the temporary suppression of the fly density. Based on the results obtained, the following control system was worked out. 1) Refuse is disposed onto the same area as other inorganic wastes to deteriorate the capacity of breeding sources. 2) The fly density is examined on newly disposed refuse almost everyday by landfill operators. 3) PEL is sprayed when the density slightly exceeds the control threshold density. If the density increases rather higher, insecticide should be used. 4) The disposed refuse is covered with soil or other inorganic wastes on every weekend or every other weekend by 15 cm thickness. Success in both fly control and reduction of the amounts of insecticides sprayed was achieved by a field application of this new control system.     

Control of insecticide resistance in a field population of houseflies,Musca domestica, by releasing susceptible flies

Summary Susceptible houseflies,Musca domestica, were released at a waste disposal site to control insecticide resistance in a field housefly population. In the first experiment, a total of 163,000 pupae of the susceptible Takatsuki strain were released in October–November 1977. LD₅₀ values to fenitrothion and diazinon decreased to about one-sixth in April 1978, five months after the releases, of those before the releases. For the second experiment, a susceptible colony was derived by cross and backcross between a white-eyed substrain of the Takatsuki and a field colony. This susceptible colony consisted of whiteeyed flies with low activity and normal-eyed flies bearing no or one white eye gene. The results of large cage experiments suggested that the normal-eyed males of the susceptible colony had half the mating competitiveness of wild males. Approximately 31,000–46,000 susceptible pupae were used in each of five releases from October to November 1980. The population number of each sex, estimated by a mark-release-recapture method, increased from 12,000 in late September to 35,000–43,000 in middle November and then decreased to 5,000–8,000 in early December. The frequency of field-collected males bearing one white eye gene and those bearing one male determining factor, which were characteristics of the susceptible colony released, increased gradually during the period of releases. The susceptibility of the field population to fenitrothion and diazinon was examined five times in the period from September to December 1980. With time, the dosage-mortality regression gradually shifted towards that of the susceptible colony after starting the releases. LD₅₀ values to fenitrothion and diazinon decreased to about one-sixth and one-fifth, respectively, in June 1981, six months after the second series of susceptible fly releases, of those before the releases. Ratios of the wild flies to the released fiies were estimated to be between 4.7∶1 and 9.8∶1 in males and between 3.0∶1 and 3.9∶1 in females by taking the quality of the released colony and the population parameters of the field houseflies into consideration. Under several assumptions, the manner of resistant phenotype reduction was discussed, based on the dosage-mortality regressions and the ratios of released flies. These results showed that the releases of susceptible flies were successful in suppression of insecticide resistance in the field housefly population.     

Job Volatility of Rural,Low-income Mothers: A Mixed Methods Approach

The struggle for rural, low-income mothers to enter and remain in the workforce can contribute to job volatility, longitudinal changes in employment patterns. This study used a mixed methods longitudinal approach to examine job volatility of 245 rural, low-income mothers across 14 states. The mothers were categorized into three groups: stable employment, intermittent employment, and continuous unemployment. Work and family responsibilities were a continuous struggle for these mothers. Some mothers addressed these struggles through changing jobs, receiving social support, and/or staying out of the workforce to care for their children. To reduce job volatility, both qualitative and quantitative analyses showed that human capital development requires workplace flexibility and social support in addition to the traditional investments in education and healthcare.