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41.
In this paper, we consider the problem of enumerating all maximal motifs in an input string for the class of repeated motifs with wild cards. A maximal motif is such a representative motif that is not properly contained in any larger motifs with the same location lists. Although the enumeration problem for maximal motifs with wild cards has been studied in Parida et al. (2001), Pisanti et al. (2003) and Pelfrêne et al. (2003), its output-polynomial time computability has been still open. The main result of this paper is a polynomial space polynomial delay algorithm for the maximal motif enumeration problem for the repeated motifs with wild cards. This algorithm enumerates all maximal motifs in an input string of length n in O(n 3) time per motif with O(n) space, in particular O(n 3) delay. The key of the algorithm is depth-first search on a tree-shaped search route over all maximal motifs based on a technique called prefix-preserving closure extension. We also show an exponential lower bound and a succinctness result on the number of maximal motifs, which indicate the limit of a straightforward approach. The results of the computational experiments show that our algorithm can be applicable to huge string data such as genome data in practice, and does not take large additional computational cost compared to usual frequent motif mining algorithms. This work is done during the Hiroki Arimura’s visit in LIRIS, University Claude-Bernard Lyon 1, France.  相似文献   
42.
Author of the highly acclaimed Borrowed Time: An AIDS Memoir (1988) and winner of the 1992 National Book Award for his autobiography Becoming a Man: Half a Life Story, Paul Monette died of complications from AIDS in Los Angeles on February 12, 1995. His most recent work, Last Watch of the Night: Essays Too Personal and Otherwise (1994), is his third volume in a trilogy of autobiographical writing on growing up gay, coming-out, and living with AIDS. A graduate of Phillips Academy and Yale University, Monette received a number of awards for his writing and his work as an outspoken voice in the battle against AIDS, including the National Book Award, three Lambda Literary awards, the PEN Center West Freedom to Write Award, and three honorary doctorate degrees, from Wesleyan University, the City University of New York, and the State University of New York at Oswego. A memorial service was held for Monette on Sunday, February 19, 1995, at the Directors Guild of America on Sunset Boulevard in Los Angeles. Paul Monette was 49.  相似文献   
43.
Support to frail elders is of international and growing importance. This article compared receipt of assistance with ADL limitations, home health help, any assistance received, and unmet needs in functionally impaired individuals aged 70 years old or older in the United States (n = 1847, 80% women, M age = 80 years) and Great Britain (n = 1203, 57% women, M age = 78 years). Informal and formal assistance levels were higher in Great Britain, and rates of unmet need did not differ across ADL domains measured. Receipt of formal and informal care were associated positively, which is consistent with both supplementary and complementary perspectives on the formal-informal care interface. Few individuals in either country received formal services alone. Results suggest that community-based formal support does not substitute for family help. Implications for family and economic policy are discussed.  相似文献   
44.
German law (§ 2079 of the Civil Code) provides for the rescission of a generally binding joint will or contract of inheritance if a surviving spouse has remarried. The law assumes that the spouse has been mistaken in the motivation for making the will. If the surviving spouse has not remarried, but cohabited with a new partner, the rescission may similarly be effected by applying § 2078 par. 2 of the Civil Code. The live-in partner will benefit from the rescission if the surviving spouse has named him or her as the successor of the deceased spouse. He or she may indeed have a right of rescission even if the partner has died without rescinding the joint will.  相似文献   
45.
Radio frequency identification (RFID) has been used to improve business supply chain management for over 35 years. As often happens, private sector technology migrates to the public sector where it is adapted for use. RFID use in governments is spreading far and wide at the federal and state levels with virtually no debate or performance analyses to inform adoption decisions. Implementation of RFID technology impacts government efficiency and effectiveness in many areas. Data show that most RFID applications promise enhanced effectiveness but also pose increased costs. A model is constructed to assist state and local managers in choosing to adopt RFID and to discern the status and impacts of this bold new innovation.
Elizabeth RudinEmail:

Barbara L. Neuby PhD   is an Associate Professor who teaches and researches in the areas of Budgeting and Security Administration in the Master of Public Administration program at Kennesaw State University. Dr. Neuby participates in various financial and emergency preparedness efforts at the state and local level. Elizabeth Rudin   graduated from Kennesaw State University in August of 2008 with a Master of Public Administration degree where she focused her research on emergency management. Ms. Rudin is currently employed in municipal government in Georgia.  相似文献   
46.
We use data from the Fragile Families and Child Wellbeing Study to investigate the association between coparenting quality and nonresident fathers' involvement with children over the first five years after a nonmarital birth. We find that about one year after a nonmarital birth, 48% of fathers are living away from their child, rising to 56% and then to 63% at three and five years, respectively Using structural equation models to estimate cross-lagged effects, we find that positive coparenting is a strong predictor of nonresident fathers' future involvement, whereas fathers' involvement is only a weak (but significant) predictor of future coparenting quality. The positive effect of coparenting quality on fathers' involvement is robust across several techniques designed to address unobserved heterogeneity and across different strategies for handling missing data. We conclude that parents' ability to work together in rearing their common child across households helps keep nonresident fathers connected to their children and that programs aimed at improving parents' ability to communicate may have benefits for children irrespective of whether the parents' romantic relationship remains intact.  相似文献   
47.
Schmidt L 《Demography》2008,45(2):439-460
The existing literature on marriage and fertility decisions pays little attention to the roles played by risk preferences and uncertainty. However given uncertainty regarding the availability of suitable marriage partners, the ability to contracept, and the ability to conceive, women's risk preferences might be expected to play an important role in marriage and fertility timing decisions. By using data from the Panel Study of Income Dynamics (PSID), I find that measured risk preferences have a significant effect on the timing of both marriage and fertility. Highly risk-tolerant women are more likely to delay marriage, consistent with either a search model of marriage or a risk-pooling explanation. In addition, risk preferences affect fertility timing in a way that differs by marital status and education, and that varies over the life cycle. Greater tolerance for risk leads to earlier births at young ages, consistent with these women being less likely to contracept effectively. In addition, as the subgroup of college-educated, unmarried women nears the end of their fertile periods, highly risk-tolerant women are likely to delay childbearing relative to their more risk-averse counterparts and are therefore less likely to become mothers. These findings may have broader implications for both individual and societal well-being.  相似文献   
48.
Molla MT  Lubitz J 《Demography》2008,45(1):115-128
Healthy life expectancies are almost always calculated by using health data from cross-sectional surveys. This type of calculation is done partly because data from longitudinal surveys are not always available, and when they are available, they are collected at intervals that are longer than one year. In such cases, collecting health information retrospectively for the years skipped by the survey is useful. The main purpose of this paper is to show how retrospective health information can be used to estimate life expectancies in different health states. Healthy life expectancies are estimated with and without using data on retrospective health information, and the corresponding estimates are compared. The two sets of estimates are similar. We conclude that retrospectively assessed health information based on a one-year recall period can be used to estimate years of life in various health states and that estimates based on such information will closely approximate estimates based on concurrent health information.  相似文献   
49.
Desai S  Kulkarni V 《Demography》2008,45(2):245-270
Indian society suffers from substantial inequalities in education, employment, and income based on caste and ethnicity. Compensatory or positive discrimination policies reserve 15% of the seats in institutions of higher education and state and central government jobs for people of the lowest caste, the Scheduled Caste; 7.5% of the seats are reserved for the Scheduled Tribe. These programs have been strengthened by improved enforcement and increased funding in the 1990s. This positive discrimination has also generated popular backlash and on-the-ground sabotage of the programs. This paper examines the changes in educational attainment between various social groups for a period of nearly 20 years to see whether educational inequalities have declined over time. We use data from a large national sample survey of over 100,000 households for each of the four survey years--1983, 1987-1988, 1993-1994, and 1999-2000--and focus on the educational attainment of children and young adults aged 6-29. Our results show a declining gap between dalits, adivasis, and others in the odds of completing primary school. Such improvement is not seen for Muslims, a minority group that does not benefit from affirmative action. We find little improvement in inequality at the college level. Further, we do not find evidence that upper-income groups, the so-called creamy layer of dalits and adivasis, disproportionately benefit from the affirmative action programs at the expense of their lower-income counterparts.  相似文献   
50.
Moving and union dissolution   总被引:1,自引:0,他引:1  
Boyle PJ  Kulu H  Cooke T  Gayle V  Mulder CH 《Demography》2008,45(1):209-222
This paper examines the effect of migration and residential mobility on union dissolution among married and cohabiting couples. Moving is a stressful life event, and a large, multidisciplinary literature has shown that family migration often benefits one partner (usually the man) more than the other Even so, no study to date has examined the possible impact of within-nation geographical mobility on union dissolution. We base our longitudinal analysis on retrospective event-history data from Austria. Our results show that couples who move frequently have a significantly higher risk of union dissolution, and we suggest a variety of mechanisms that may explain this.  相似文献   
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