Life analysis of restored and refurbished bearings

An analysis of the potential life of refurbished and restored bearings was performed. The sensitivity of 10-percent life and mean-time-between-failure to the effects of cumulative fatigue damage and the amount of stressed volume removed in the restoration process were examined. A modified Lundberg-Palmgren theory was used to predict that the expected 10-percent life of a restored bearing, which is dependent on the previous service time and the volume of material removed from the race surfaces, can be between 74 and 100 percent of the new bearing life. Using renewal theory, it is found that the mean time between failure ranged from 90 to 100 percent of that for a new bearing

Immunization coverage and risk factors for failure to immunize within the Expanded Programme on Immunization in Kenya after introduction of new Haemophilus influenzae type b and hepatitis b virus antigens

Background: Kenya introduced a pentavalent vaccine including the DTP, Haemophilus influenzae type b and hepatitis b virus antigens in Nov 2001 and strengthened immunization services. We estimated immunization coverage before and after introduction, timeliness of vaccination and risk factors for failure to immunize in Kilifi district, Kenya. Methods: In Nov 2002 we performed WHO cluster-sample surveys of > 200 children scheduled for vaccination before or after introduction of pentavalent vaccine. In Mar 2004 we conducted a simple random sample (SRS) survey of 204 children aged 9 - 23 months. Coverage was estimated by inverse Kaplan-Meier survival analysis of vaccine- card and mothers' recall data and corroborated by reviewing administrative records from national and provincial vaccine stores. The contribution to timely immunization of distance from clinic, seasonal rainfall, mother's age, and family size was estimated by a proportional hazards model. Results: Immunization coverage for three DTP and pentavalent doses was 100% before and 91% after pentavalent vaccine introduction, respectively. By SRS survey, coverage was 88% for three pentavalent doses. The median age at first, second and third vaccine dose was 8, 13 and 18 weeks. Vials dispatched to Kilifi District during 2001 - 2003 would provide three immunizations for 92% of the birth cohort. Immunization rate ratios were reduced with every kilometre of distance from home to vaccine clinic (HR 0.95, CI 0.91 - 1.00), rainy seasons ( HR 0.73, 95% CI 0.61 - 0.89) and family size, increasing progressively up to 4 children ( HR 0.55, 95% CI 0.41 - 0.73). Conclusion: Vaccine coverage was high before and after introduction of pentavalent vaccine, but most doses were given late. Coverage is limited by seasonal factors and family siz

Patterns of Intergenerational Transfers in Southeast Asia

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73942/1/j.1741-3737.2002.00627.x.pd

Parents’ Disclosure of Their HIV Infection to Their Children in the Context of the Family

We interviewed 33 HIV-infected parents from the HIV Cost and Services Utilization Study (HCSUS), 27 of their minor children, 19 adult children, and 15 caregivers about the process of children learning that their parents were HIV positive. We summarize the retrospective descriptions of parents’ disclosure of their HIV status to their children, from the perspective of multiple family members. We analyzed transcripts of these interviews with systematic qualitative methods. Both parents and children reported unplanned disclosure experiences with positive and negative outcomes. Parents sometimes reported that disclosure was not as negative as they feared. However, within-household analysis showed disagreement between parents and children from the same household regarding disclosure outcomes. These findings suggest that disclosure should be addressed within a family context to facilitate communication and children’s coping. Parents should consider negative and positive outcomes, unplanned disclosure and children’s capacity to adapt after disclosure when deciding whether to disclose

HIV Disease Impact on Mothers: What They Miss During Their Children’s Developmental Years

Adjusting to chronic illness is very complicated for families with children, as they are already faced with the challenge of development and childrearing. In this study, qualitative interviews were conducted with HIV positive mothers on a number of issues related to being an HIV positive mother raising young children. One topic of the interview was whether or not they felt that HIV had caused them to miss activities with their children while the children were growing up, what types of activities they had missed, the age of the child for each example, and how HIV had led to missing these activities. Interviews were conducted in 2008 with a random sample of 57 mothers being followed in a longitudinal assessment study. All study participants were English or Spanish speaking. Mean age was 44.1 (SD = 5.6) years; 47% were Latina; 35% African American; 11% White; and 7% other race. About 60% of the mothers disclosed that their HIV status had caused them to miss out on activities with their children while their children were growing up, ranging from daily care activities to major school and extra-curricular activities. Some mothers missed significant amounts of time with their children due to hospitalizations. In some cases mothers felt forced into a choice between mothering ability and their own health, including adherence to medications. Implications for the mothers and the children are discussed

Fluvastatin synergistically enhances the antiproliferative effect of gemcitabine in human pancreatic cancer MIAPaCa-2 cells

The new combination between the nucleoside analogue gemcitabine and the cholesterol-lowering drug fluvastatin was investigated in vitro and in vivo on the human pancreatic tumour cell line MIAPaCa-2. The present study demonstrates that fluvastatin inhibits proliferation, induces apoptosis in pancreatic cancer cells harbouring a p21ras mutation at codon 12 and synergistically potentiates the cytotoxic effect of gemcitabine. The pharmacologic activities of fluvastatin are prevented by administration of mevalonic acid, suggesting that the shown inhibition of geranyl-geranylation and farnesylation of cellular proteins, including p21rhoA and p21ras, plays a major role in its anticancer effect. Fluvastatin treatment also indirectly inhibits the phosphorylation of p42ERK2/mitogen-activated protein kinase, the cellular effector of ras and other signal transduction peptides. Moreover, fluvastatin administration significantly increases the expression of the deoxycytidine kinase, the enzyme required for the activation of gemcitabine, and simultaneously reduces the 5′-nucleotidase, responsible for deactivation of gemcitabine, suggesting a possible additional role of these enzymes in the enhanced cytotoxic activity of gemcitabine. Finally, a significant in vivo antitumour effect on MIAPaCa-2 xenografts was observed with the simultaneous combination of fluvastatin and gemcitabine, resulting in an almost complete suppression and a marked delay in relapse of tumour growth. In conclusion, the combination of fluvastatin and gemcitabine is an effective cytotoxic, proapoptotic treatment in vitro and in vivo against MIAPaCa-2 cells by a mechanism of action mediated, at least in part, by the inhibition of p21ras and rhoA prenylation. The obtained experimental findings might constitute the basis for a novel translational research in humans

The scale, governance, and sustainability of central places in pre-Hispanic Mesoamerica

Examinations of the variation and relative successes or failures of past large-scale societies have long involved attempts to reconcile efforts at generalization and the identification of specific factors with explanatory value for regional trajectories. Although historical particulars are critical to understanding individual cases, there are both scholarly and policy rationales for drawing broader implications regarding the growing corpus of cross-cultural data germane to understanding variability in the constitution of human societies, past and present. Archaeologists have recently highlighted how successes and failures in communal-resource management can be studied over the long term through the material record to both engage and enhance transdisciplinary research on cooperation and collective action. In this article we consider frameworks that have been traditionally employed in studies of the rise, diversity, and fall of preindustrial urban aggregations. We suggest that a comparative theoretical perspective that foregrounds collective-action problems, unaligned individual and group interests, and the social mechanisms that promote or hamper cooperation advances our understanding of variability in these early cooperative arrangements. We apply such a perspective to an examination of pre-Hispanic Mesoamerican urban centers to demonstrate tendencies for more collective systems to be larger and longer lasting than less collective ones, likely reflecting greater sustainability in the face of the ecological and cultural perturbations specific to the region and era.Accepted manuscrip

Estimating Individual Exposure to Malaria Using Local Prevalence of Malaria Infection in the Field

BACKGROUND: Heterogeneity in malaria exposure complicates survival analyses of vaccine efficacy trials and confounds the association between immune correlates of protection and malaria infection in longitudinal studies. Analysis may be facilitated by taking into account the variability in individual exposure levels, but it is unclear how exposure can be estimated at an individual level. METHOD AND FINDINGS: We studied three cohorts (Chonyi, Junju and Ngerenya) in Kilifi District, Kenya to assess measures of malaria exposure. Prospective data were available on malaria episodes, geospatial coordinates, proximity to infected and uninfected individuals and residence in predefined malaria hotspots for 2,425 individuals. Antibody levels to the malaria antigens AMA1 and MSP1(142) were available for 291 children from Junju. We calculated distance-weighted local prevalence of malaria infection within 1 km radius as a marker of individual's malaria exposure. We used multivariable modified Poisson regression model to assess the discriminatory power of these markers for malaria infection (i.e. asymptomatic parasitaemia or clinical malaria). The area under the receiver operating characteristic (ROC) curve was used to assess the discriminatory power of the models. Local malaria prevalence within 1 km radius and AMA1 and MSP1(142) antibodies levels were independently associated with malaria infection. Weighted local malaria prevalence had an area under ROC curve of 0.72 (95%CI: 0.66-0.73), 0.71 (95%CI: 0.69-0.73) and 0.82 (95%CI: 0.80-0.83) among cohorts in Chonyi, Junju and Ngerenya respectively. In a small subset of children from Junju, a model incorporating weighted local malaria prevalence with AMA1 and MSP1(142) antibody levels provided an AUC of 0.83 (95%CI: 0.79-0.88). CONCLUSION: We have proposed an approach to estimating the intensity of an individual's malaria exposure in the field. The weighted local malaria prevalence can be used as individual marker of malaria exposure in malaria vaccine trials and longitudinal studies of natural immunity to malaria