2,994 research outputs found
Why don't households invest in latrines: Health, prestige, or safety?
70 percent of the rural population in sub-Saharan Africa does not use adequate sanitation facilities. In rural Benin, as much as 95 percent of the population has no access to improved sanitation. This paper explores why households remain without latrines analyzing a representative sample of 2000 rural households. Our results show that wealth and latrine prices play the most decisive role for sanitation demand and ownership. At current income levels, sanitation coverage will only increase to 50 percent if costs for construction are reduced from currently 50 USD per latrine. Our analysis also suggests that previous sanitation promotion campaigns, which were based on prestige and modern lifestyle as motives for latrine construction, have had no success in increasing sanitation coverage. Moreover, improved public health, which is the objective of public policies promoting sanitation, is also difficult to achieve at low sanitation coverage rates. Fear at night, especially of animals, and personal harassment, are stated as the most important motivational factors for latrine ownership and the intention to build one. We therefore suggest that new low cost technologies should be introduced on rural markets and that social marketing strategies should be adjusted accordingly
Women: Walking and Waiting for Water The Time Value of Public Water Supply
Public funding of water supply infrastructure in developing countries is often justified by the expectation that the time spent on water collection significantly decreases, leading to increased labor force participation of women. In this study we empirically test this hypothesis by applying a difference-in-difference analysis to a sample of 2000 households in rural Benin where improved water supply was phased in over time. Time savings per day are rather modest at 35 minutes: even though walking distances are considerably reduced, women still spend a lot of time waiting at the water source. Moreover, a reduction in time to collect one water container induces women to collect a higher number of containers per day. Our results indicate that time savings are rarely followed by increased labor supply of women: men are the first to be freed from water fetching activities
Tooth-Colored CAD/CAM Materials for Application in 3-Unit Fixed Dental Prostheses in the Molar Area: An Illustrated Clinical Comparison
The aim of this study was to compare the clinical properties of tooth-colored computer-aided design/computer-aided manufacturing (CAD/CAM) materials for the fabrication of a 3-unit fixed dental prostheses (FDPs) in the same clinical scenario. A 53-year-old female patient was supplied with a 3-unit FDP to replace a second premolar in the upper jaw. Restorations were fabricated from 3 mol%, 4 mol%, and 5 mol% yttrium oxide zirconia, zirconia with translucency gradient, indirect composite resin, polyetheretherketone (PEEK), and polyetherketoneketone (PEKK). Milling time, weight, and radiopacity were investigated. Esthetics were examined following the US Public Health Service criteria (USPHS). The milling time for zirconia was twice as high as for the indirect composite resin, PEEK, or PEKK. The latter materials had a weight of 2 g each, while zirconia restorations yielded 5 g. Zirconia presented intense radiopacity. PEEK and PEKK required veneering and an opaquer was applied to the PEKK framework. All FDPs showed acceptable esthetics. PEEK and PEKK restorations were featured by a grayish shimmering. A variety of CAD/CAM materials are available to fabricate 3-unit FDPs with esthetically acceptable results. In the esthetic zone, PEEK and PEKK require veneering and an opaquer might be applied. Milling time, weight, and radiopacity were relatively high for zirconia FDPs
Utilization of dental services and health literacy by older seniors during the COVID-19 pandemic
Background: This study aimed to investigate the utilization of dental services by older seniors during the COVID-19 pandemic and to evaluate their ability of finding, understanding, and using information on COVID-19.
Methods: At the end of February 2021, a survey addressing demographic characteristics of the participants, (pain-associated) utilization of dental services, worries regarding a potential COVID-19 infection, the individual use of protective masks, and difficulties regarding the access to information on COVID-19 (by using the modified European Health Literacy Questionnaire [HLS-EU-Q16]) was developed. It was sent to all patients of the Dental Clinic of University of Leipzig who were either 75, 80, or 85 years old (n = 1228). Participation was voluntarily and anonymously; questionnaires had to be returned within six weeks, no reminders were sent.
Results: Of the 439 replies (response rate 35.7%), twelve were excluded from data extraction due to disinterest, dementia, or lack of age information. Of the older seniors, 81.5% (n = 348) had utilized at least one dental examination and 54.2% of the dentulous patients (n = 199) had attended at least one dental hygiene appointment within the past year. Up to 55.8% of all participants said it was "difficult" or "very difficult" to find, understand, and use information on COVID-19, especially when judging reliability of information presented in the media, which was especially true for seniors with assigned care levels presenting odds ratios up to 5.30.
Conclusions: The investigation revealed a frequent utilization of dental services by older seniors during the COVID-19 pandemic. However, the older seniors encountered difficulties finding, using, and understanding information about COVID-19.
Keywords: COVID-19; geriatric dentistry; gerodontology; health literacy; older seniors; utilization
Leveraging Trust and Privacy Concerns in Online Social Networks: an Empirical Study
Unprecedented success of Online Social Networks, such as Facebook, has been recently overshadowed by the privacy risks they imply. Weary of privacy concerns and unable to construct their identity in the desired way, users may restrict or even terminate their platform activities. Even though this means a considerable business risk for these platforms, so far there have been no studies on how to enable social network providers to address these problems. This study fills this gap by adopting a fairness perspective to analyze related measures at the disposal of the provider. In a Structural Equation Model with 237 subjects we find that ensuring interactional and procedural justice are two important strategies to support user participation on the platform
Women Are Walking and Waiting for Water: The Time Value of Public Water Supply
Funding of the public water supply in developing countries is often justified by the expectation that it significantly decreases the time spent on water collection, leading to increased labor force participation of women. We empirically test this hypothesis for rural Benin. Daily water collection times are reduced by 41 minutes but still take 2 hours after the installation of a public pump. Even though walking distances are reduced, women still spend a lot of time waiting at the water source, and not all women use the improved water source. Moreover, a reduction in time to fill one water container induces women to fill more containers per day. Time savings are rarely followed by an increase in the labor supply of women. The economic value of the annual time savings is 1%–2% of a rural households’ income
polaron pair vs. bipolaron
The molecular structure of a cyclic oligothiophene, C10T, has been determined
by single-crystal X-ray structure analysis. The exclusive syn-conformation of
all thiophene units as confirmed in the solid state and the ring strain in
this macrocycle result in its unusual and optoelectronic properties. This does
not only apply to neutral C10T but also to its oxidized states, as
demonstrated by absorption and ESR spectroscopy, supporting the formation of a
polaron-pair structure upon oxidation of C10T to C10T2(·+) as has been
discussed for linear oligothiophenes. To the best of our knowledge, C10T2(·+)
represents an unambiguous example comprising a two-polaron structure (polaron-
pair) of a thiophene-based conjugated macrocycle
Contribution of early acute rejection episodes to chronic rejection in a rat kidney retransplantation model
Contribution of early rejection episodes to chronic rejection in a kidney retransplantation model. Chronic graft rejection represents the single most important risk factor for unsatisfactory long-term results after organ transplantation. In addition to various alloantigen dependent and independent factors, acute rejection episodes have been cited as a major immunological risk factor. However, the effects of acute rejection episodes on long-term graft outcome remains unknown. To examine the influence of a single early rejection event on ultimate graft outcome, acutely rejecting rat kidney grafts were retransplanted sequentially into syngeneic rats and their functional and structural behavior assessed over time. LEWxBNF1 kidney allografts and LEW isografts were removed from their LEW recipients after three, four, five and seven days (N = 12/group/time period) and retransplanted into donor strain hosts. The grafts were followed functionally and harvested four, eight, and 32 weeks later. Urinary protein excretion was measured weekly. Kidneys were examined morphologically and immunohistologically using monoclonal antibodies (mAbs) against macrophages (ED-1), T cells and their subsets (CD5, CD4, CD8), MHC class II expression (OX3) and adhesion molecules (ICAM-1 and LFA-1α). The mean standard time ±SD of non-retransplanted allografts was 14.5 ± two days; isografts functioned indefinitely. At five and seven days, acutely rejecting allografts showed massive cellular infiltrates associated with extensive necrosis. These changes could not be reversed by retransplantation and the syngeneic recipients later died of renal failure. In contrast, most allografts retransplanted earlier in the process recovered completely when retransplanted after three (12 of 12 allografts) and four (7 of 12 allografts) days. During the subsequent follow-up period, urinary protein excretion was comparable in retransplanted allografts and isografts. The increased mononuclear cell infiltration in non-retransplanted allografts seen at three and four days was only occasionally observed during the follow-up period after retransplantation. Only a few sclerosed glomeruli (∼15%), mild arterial changes and minimal cellular infiltrates were observed by 32 weeks, which were similar to that seen in retransplanted isografts. A single acute rejection episode was completely reversible and did not progress to chronic rejection if retransplanted into syngeneic donors when the inflammatory changes are still early. Those results demonstrate the critical effect of alloantigen-dependent events on chronic graft deterioration, and indicate that prompt and aggressive treatment of initial acute rejection episodes are beneficial to protect against late deleterious changes in the graft
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