Incrimination of shrews as a reservoir for Powassan virus.

Powassan virus lineage 2 (deer tick virus) is an emergent threat to American public health, causing severe neurologic disease. Its life cycle in nature remains poorly understood. We use a host-specific retrotransposon-targeted real time PCR assay to test the hypothesis that white-footed mice, considered the main eastern U.S. reservoir of the coinfecting agent of Lyme disease, is the reservoir for deer tick virus. Of 20 virus-infected host-seeking nymphal black-legged ticks 65% fed on shrews and none on mice. The proportion of ticks feeding on shrews at a site is positively associated with prevalence of viral infection, but not the Lyme disease agent. Viral RNA is detected in the brain of one shrew. We conclude that shrews are a likely reservoir host for deer tick virus and that host bloodmeal analysis can provide direct evidence to incriminate reservoir hosts, thereby promoting our understanding of the ecology of tick-borne infections.

The Financial Burden Of Paid Home Care On Older Adults: Oldest And Sickest Are Least Likely To Have Enough Income.

Paid home care can significantly improve the lives of older adults with disabilities and their families, but recipients often incur substantial out-of-pocket spending. We simulated the financial burden of paid home care for a nationally representative sample of non-Medicaid community-dwelling adults ages sixty-five and older. We found that 74 percent could fund at least two years of a moderate amount of paid home care if they liquidated all of their assets, and 58 percent could fund at least two years of an extensive amount of paid home care. Among older adults with significant disabilities, however, only 57 percent could fund at least two years of moderate paid home care by liquidating all of their assets, and 40 percent could fund at least two years of extensive paid home care. Paid home care could become less affordable if growing labor shortages raise future costs.

Hispanics' Retirement Transitions and Differences by Nativity.

OBJECTIVE: This study examines differences in retirement decisions between older Hispanics and non-Hispanics, with a special focus on the role of nativity. METHODS: We use 1998-2012 waves of the Health and Retirement Study. We estimate survival models of retirement and compare retirement transitions for U.S.-born Hispanics, foreign-born Hispanics, non-Hispanic Whites, and non-Hispanic Blacks. RESULTS: Foreign-born Hispanics retire significantly later than other racial and ethnic groups. Controlling for personal characteristics, their risk of retirement is 39% lower compared with non-Hispanic Whites. Retirement transitions do not differ significantly between U.S.-born Hispanics and non-Hispanic Whites. DISCUSSION: Difference in retirement timing between U.S.- and foreign-born Hispanics may partly be due to lower incomes and wealth accumulation of foreign-born Hispanics. Workforce development initiatives, policy initiatives promoting retirement savings, and Social Security reforms could improve future retirement security for older Hispanics, and make retirement a viable option for more foreign-born Hispanics.

Financing Long-Term Services And Supports: Options Reflect Trade-Offs For Older Americans And Federal Spending.

About half of older Americans will need a high level of assistance with routine activities for a prolonged period of time. This help is commonly referred to as long-term services and supports (LTSS). Under current policies, these individuals will fund roughly half of their paid care out of pocket. Partly as a result of high costs and uncertainty, relatively few people purchase private long-term care insurance or save sufficiently to fully finance LTSS; many will eventually turn to Medicaid for help. To show how policy changes could expand insurance's role in financing these needs, we modeled several new insurance options. Specifically, we looked at a front-end-only benefit that provides coverage relatively early in the period of disability but caps benefits, a back-end benefit with no lifetime limit, and a combined comprehensive benefit. We modeled mandatory and voluntary versions of each option, and subsidized and unsubsidized versions of each voluntary option. We identified important differences among the alternatives, highlighting relevant trade-offs that policy makers can consider in evaluating proposals. If the primary goal is to significantly increase insurance coverage, the mandatory options would be more successful than the voluntary versions. If the major aim is to reduce Medicaid costs, the comprehensive and back-end mandatory options would be most beneficial.

Intrinsic and extrinsic parameters for controlling the growth of organic single-crystalline nanopillars in photovoltaics.

The most efficient architecture for achieving high donor/acceptor interfacial area in organic photovoltaics (OPVs) would employ arrays of vertically interdigitated p- and n- type semiconductor nanopillars (NPs). Such morphology could have an advantage in bulk heterojunction systems; however, precise control of the dimension morphology in a crystalline, interpenetrating architecture has not yet been realized. Here we present a simple, yet facile, crystallization technique for the growth of vertically oriented NPs utilizing a modified thermal evaporation technique that hinges on a fast deposition rate, short substrate-source distance, and ballistic mass transport. A broad range of organic semiconductor materials is beneficial from the technique to generate NP geometries. Moreover, this technique can also be generalized to various substrates, namely, graphene, PEDOT-PSS, ZnO, CuI, MoO3, and MoS2. The advantage of the NP architecture over the conventional thin film counterpart is demonstrated with an increase of power conversion efficiency of 32% in photovoltaics. This technique will advance the knowledge of organic semiconductor crystallization and create opportunities for the fabrication and processing of NPs for applications that include solar cells, charge storage devices, sensors, and vertical transistors.

Selective metal deposition at graphene line defects by atomic layer deposition.

One-dimensional defects in graphene have a strong influence on its physical properties, such as electrical charge transport and mechanical strength. With enhanced chemical reactivity, such defects may also allow us to selectively functionalize the material and systematically tune the properties of graphene. Here we demonstrate the selective deposition of metal at chemical vapour deposited graphene's line defects, notably grain boundaries, by atomic layer deposition. Atomic layer deposition allows us to deposit Pt predominantly on graphene's grain boundaries, folds and cracks due to the enhanced chemical reactivity of these line defects, which is directly confirmed by transmission electron microscopy imaging. The selective functionalization of graphene defect sites, together with the nanowire morphology of deposited Pt, yields a superior platform for sensing applications. Using Pt-graphene hybrid structures, we demonstrate high-performance hydrogen gas sensors at room temperature and show its advantages over other evaporative Pt deposition methods, in which Pt decorates the graphene surface non-selectively.

An atomic layer deposition chamber for in situ x-ray diffraction and scattering analysis.

The crystal structure of thin films grown by atomic layer deposition (ALD) will determine important performance properties such as conductivity, breakdown voltage, and catalytic activity. We report the design of an atomic layer deposition chamber for in situ x-ray analysis that can be used to monitor changes to the crystal structural during ALD. The application of the chamber is demonstrated for Pt ALD on amorphous SiO2 and SrTiO3 (001) using synchrotron-based high resolution x-ray diffraction, grazing incidence x-ray diffraction, and grazing incidence small angle scattering.

Day/night whole sky imagers for 24-h cloud and sky assessment: history and overview.

A family of fully automated digital whole sky imagers (WSIs) has been developed at the Marine Physical Laboratory over many years, for a variety of research and military applications. The most advanced of these, the day/night whole sky imagers (D/N WSIs), acquire digital imagery of the full sky down to the horizon under all conditions from full sunlight to starlight. Cloud algorithms process the imagery to automatically detect the locations of cloud for both day and night. The instruments can provide absolute radiance distribution over the full radiance range from starlight through daylight. The WSIs were fielded in 1984, followed by the D/N WSIs in 1992. These many years of experience and development have resulted in very capable instruments and algorithms that remain unique. This article discusses the history of the development of the D/N WSIs, system design, algorithms, and data products. The paper cites many reports with more detailed technical documentation. Further details of calibration, day and night algorithms, and cloud free line-of-sight results will be discussed in future articles.

Job demands and work ability at older ages.

Workers' ability to delay retirement depends partly on the demands of their jobs. Matching occupational characteristics from the Occupational Information Network to Current Population Survey respondents, this study finds that 7% of American workers held highly physically demanding jobs in 2006 and 35% held highly cognitively demanding jobs. The share of the workforce in physically demanding jobs fell by about one-sixth between 1971 and 2006, while the share in cognitively demanding jobs increased by more than one-third. The decline in physically demanding occupations will likely improve employment prospects for older adults, but the growth in cognitive demands may limit options for some older workers.

Volunteer dynamics of older Americans.

OBJECTIVES: The impending retirement of boomers has spurred interest in tapping their productive energies to benefit society. This study examined volunteer transitions among older adults to understand the factors that affect volunteer dynamics. METHODS: Using data from the Health and Retirement Study, the analysis examined entries into and exits from formal volunteer activities between 1996 and 2004 by adults aged 55-65 at study baseline. The study showed the duration of volunteer activities, the probability that older adults start and stop volunteering, and the factors that significantly predict volunteer transitions. RESULTS: The findings reveal considerable stability among both volunteers and nonvolunteers; however, older adults are more likely to stop volunteering than to start. Volunteers who contribute intensely and for many years and who are married to volunteers are the least likely to quit. And nonvolunteers are more likely to start volunteering if they have been uninvolved for few years and their spouses volunteer. CONCLUSIONS: The results point to the need to focus efforts on retaining older volunteers to maximize volunteer engagement during later years. Recruiting older adults in volunteer activities early on, ideally before they retire, could also help meet volunteer needs.

Why do boomers plan to work longer?

OBJECTIVE: . Recent changes in retirement trends and patterns have raised questions about the likely retirement behavior of baby boomers, the large cohort born between 1946 and 1964. This study examined recent changes in retirement expectations and the factors that drove them. METHODS: Using data from the Health and Retirement Study, the analysis compared self-reported probabilities of working full time past ages 62 and 65 among workers aged 51 to 56 in 1992 and 2004. The study modeled retirement expectations for both generations and used the estimated regression coefficients to identify the forces that accounted for generational differences. RESULTS: . Between 1992 and 2004, the mean self-reported probability of working full time past age 65 among workers aged 51 to 56 increased from 27% to 33%. Lower rates of retiree health insurance offers from employers, higher levels of educational attainment, and lower rates of defined benefit pension coverage accounted for most of the growth. DISCUSSION: Given the continued erosion in employer-sponsored retiree health benefits and defined benefit pension plans, boomers will likely remain at work longer than members of the previous generation. Lengthier careers will likely promote economic growth, increase government revenue, and improve individual financial security at older ages.

The impact of elder care on women's labor supply.

Adult daughters traditionally have served as primary caregivers for frail unmarried adults, but the levels of care they have provided in the past may interfere with their growing work responsibilities. This paper examines the impact of time transfers to elderly parents on labor supply at midlife. Using a sample of women ages 55 to 67 in the Health and Retirement Study, we estimate panel data models of annual hours of paid work controlling for the endogeneity of time assistance to parents. The results indicate that time help to parents strongly reduces female labor supply at midlife.

Trends in retiree health insurance, 1997-2003.

Although millions of older Americans rely on employer-sponsored retiree health benefits to help pay their medical expenses, declines in this coverage have been documented. Using data from the Medical Expenditure Panel Survey, our findings reveal steady erosion in retiree health benefits since the mid-1990s. Based on this much larger survey of private establishments than previous studies have used, we conclude that in 2003 only about one-quarter of private-sector employees worked at establishments that offered health benefits to retirees, down from 32 percent in 1997. Private firms have also been passing higher shares of health insurance costs to retirees.

Who foregoes survivor protection in employer-sponsored pension annuities?

PURPOSE: Retirees in traditional pension plans must generally choose between single life annuities, which provide regular payments until death, and joint and survivor annuities, which pay less each month but continue to make payments to the spouse after the death of the retired worker. This article examines the payout decision and measures the share of married retirees with pension annuities who forego survivor protection. DESIGN AND METHODS: The analysis consists of a probit model of the pension payout decision, based on data from the 1992-2000 waves of the Health and Retirement Study. RESULTS: More than one quarter (28%) of married men and two thirds of married women receiving employer-sponsored retirement annuities declined survivor protection. Men with small pensions and limited household wealth, men in better health than their spouses, and men whose spouses have pension coverage from their own employers are more likely than other men to reject survivor protection. IMPLICATIONS: Most workers appear to make payout decisions by rationally balancing the costs and benefits of each type of annuity, suggesting that existing measures to encourage joint and survivor annuities are adequate. However, the growth in 401(k) plans, which are generally not covered by existing laws protecting spousal pension rights, may leave widows vulnerable.

Economic status in later life among women who raised children outside of marriage.

OBJECTIVE: Many single mothers are likely to face special economic challenges in old age, because they often have limited employment histories and cannot rely on husbands for financial support. This article examines the economic status of these women in later life. METHODS: The analysis uses nationally representative data from the Health and Retirement Study to estimate multivariate models of income, assets, and poverty rates for women aged 65-75 in 1999. RESULT: Controlling for education, current marital status, and race and ethnicity, the models indicate that women who spent > or =10 years raising dependent children outside of marriage are 55% more likely to live in poverty at ages 65-75 than women who were always married when their children were young. DISCUSSION: The financial difficulties confronting single mothers raising children persist into later life. Social Security reforms, especially those that are not tied to the current system of spousal and survivor benefits, could improve retirement security for these vulnerable women, whose numbers will begin to soar when the many women who raised children outside of marriage in the 1970s retire in coming years.

Raising the Medicare eligibility age: effects on the young elderly.

If Medicare eligibility were delayed to age sixty-seven, as proposed periodically by policymakers, most sixty-five- and sixty-six-year-olds (the "young elderly") would find alternative sources of coverage. However, the loss of Medicare eligibility would leave about 9 percent of this age group uninsured, while another 11 percent would be underinsured because they could only afford limited nongroup policies. The impact would be much greater for certain subgroups, including blacks, Hispanics, and the poor. A buy-in plan that allows young elderly people to purchase Medicare coverage could reduce uninsurance rates, but only if it subsidizes premiums for those with limited incomes.

Does informal care from adult children reduce nursing home admissions for the elderly?

Despite the policy importance, particularly as society ages, little is known about the impact of informal care on nursing home admissions. This paper jointly models the receipt of regular help from adult children and subsequent nursing home care, using data from the Study of Asset and Health Dynamics Among the Oldest Old (AHEAD). Results indicate that frequent help from children with basic personal care reduces the likelihood of nursing home use over a subsequent two-year period by about 60% for disabled Americans age 70 and older. However, we found no significant reduction in nursing home admissions when help was measured more broadly to include assistance with chores and errands.

Synovial osteochondromatosis. A case report and review of the literature.

Synovial osteochondromatosis is a benign disease of unknown etiology that involves the articular and periarticular structures. The disorder primarily affects men, and trauma is the most common predisposing factor. The authors review the literature, clinical findings, proposed etiology, classification, ancillary tests, histopathology, differential diagnosis, treatment options, and prognosis. A case report of this rare entity is also presented.