5,834 research outputs found
Village economies and the structure of extended family networks
This paper documents how the structure of extended family networks in rural Mexico relates to the poverty and inequality of the village of residence. Using the Hispanic naming convention, we construct within-village extended family networks in 504 poor rural villages. Family networks are larger (both in the number of members and as a share of the village population) and out-migration is lower the poorer and the less unequal the village of residence. Our results are consistent with the extended family being a source of informal insurance to its members
Family networks and school enrolment: evidence from a randomized social experiment
We present evidence on whether and how a householdâs behavior is influenced by the
presence and characteristics of its extended family. Using data from the PROGRESA
program in Mexico, we exploit information on the paternal and maternal surnames of
heads and spouses in conjunction with the Spanish naming convention to identify the inter
and intra generational family links of each household to others in the same village. We
then exploit the randomized research design of the PROGRESA evaluation data to identify
whether the treatment effects of PROGRESA transfers on secondary school enrolment
vary according to the characteristics of extended family. We find PROGRESA only raises
secondary enrolment among households that are embedded in a family network. Eligible
but isolated households do not respond. The mechanism through which the extended
family influences household schooling choices is the redistribution of resources within
the family network from eligibles that receive de facto unconditional cash transfers from
PROGRESA, towards eligibles on the margin of enrolling children into secondary school
Consumption and Investment in Resource Pooling Family Networks
This paper examines a novel motive for resource pooling in family networks in rural economies: to relax credit constraints and facilitate investment in non-collateralizeable assets for which credit market imperfections are most binding. We thus complement established literatures examining risk-sharing motives for resource transfers within family networks, as well as motives based on kinship tax obligations. We do so exploiting the Progresa program data, in which family networks can be identified, households are subject to large exogenous resource inflows, and detailed responses on consumption and an array of investments can be tracked in a household panel over five years. We find that for every dollar that accrues to the family network through Progresa transfers, food consumption expenditures increase by around 65c/ for both households eligible for Progresa and ineligible members of the same family network. Hence the marginal propensity of families to invest/save out of every dollar is around .35, and we document how this is channelled towards easing credit constraints poorer network members face in financing non-collateralizable investments into their children's human capital. We show these consumption and investment benefits of being embedded within a family network are sustained five years after households first experience resource transfers from Progresa. Hence the interplay between resource inflows and resource pooling by family networks can place network members on sustained paths out of poverty
Correlation between oesophageal acid exposure and dyspeptic symptoms in patients with nonerosive reflux disease.
Oesophageal acidification induces dyspeptic symptoms in healthy individuals. This study aimed to evaluate the correlation between oesophageal acid exposure and dyspeptic symptoms in patients with nonerosive reflux disease. METHODS: A total of 68 patients with dominant symptoms of heartburn, negative upper gastrointestinal endoscopy and concomitant dyspeptic symptoms participated in the study. The severity of dyspepsia and reflux-related symptoms was evaluated, and 24-h gastro-oesophageal pH-monitoring study was performed in all patients at baseline and after 4 weeks of therapy with esomeprazole 40 mg. RESULTS: Oesophageal basal acid exposure was pathological in 43 patients and normal in 25 patients, with a similar prevalence and severity of individual dyspeptic symptoms in the two groups. A significant correlation between reflux and dyspepsia scores was observed in the subgroup of patients with normal, but not in those with abnormal pHmetry (r=0.4, P=0.04 and r=0.2 P=0.07, respectively). After esomeprazole, a reduction in severity of dyspepsia (>or=50% with respect to baseline) was observed, independent of improvement of reflux-associated symptoms. Improvement in dyspepsia was, however, similar in patients with normal and abnormal basal acid exposure (14/25 vs. 33/43, respectively, P=NS). CONCLUSION: Dyspeptic symptoms coexist in a subset of nonerosive reflux disease patients, but prevalence and severity of the symptoms seems to be independent of oesophageal acid exposure
Experimental Detection of Entanglement with Polarized Photons
We report on the first experimental realization of the entanglement witness
for polarization entangled photons. It represents a recently discovered
significant quantum information protocol which is based on few local
measurements. The present demonstration has been applied to the so-called
Werner states, a family of ''mixed'' quantum states that include both entangled
and non entangled states. These states have been generated by a novel high
brilliance source of entanglement which allows to continuously tune the degree
of mixedness
Could different TMJ disc positions observed in MRI cause different sounds? Analysis on a group of subjects with ADD with reduction: a pilot study.
Reliability and inter-observer agreement of dermoscopic diagnosis of melanoma and melanocytic naevi
The aim of this study was to analyse the reliability and the inter- observer agreement of dermoscopy in the diagnosis of melanocytic skin lesions. Nine dermatologists, with a different training experience and who routinely used dermoscopy in different hospitals in Italy, evaluated clinical and dermoscopy photographs of 15 melanocytic lesions (four invasive melanomas, four histologically common naevi, and seven naevi with histological atypia). A further series of dermoscopic photographs of 40 melanocytic lesions was evaluated to quantify inter-observer concordance in recognizing dermoscopic criteria. Compared to the true (histological) diagnosis, clinical diagnosis (categories: melanoma, common naevus, atypical naevus) was correct in 40% of cases (range, 27-53%). The percentage raised to 55% (40-73%) by the use of dermoscopy, with an average improvement of 15.6%. Concerning melanoma, clinical diagnosis resulted in a sensitivity of 41.9%, specificity of 77.8%, positive predictive value (PPV) of 36.1%, negative predictive value (NPV) of 81.8%. By using dermoscopy, an improvement of diagnostic performance was found (sensitivity 75%, specificity 88.8%, VPP 71.0%, VPN 90.7%). The inter-observer agreement in melanoma diagnosis, by using dermoscopy, was similar to that obtained by clinical examination (k statistics = 0.54 and 0.52, respectively). Concerning dermoscopic criteria, the best agreement among observers was found for pseudopods, a dermoscopic parameter related to the radial growth phase of melanoma. We conclude that dermoscopy is an useful tool for a non-invasive diagnosis of melanocytic skin lesions, improving the diagnostic performance compared to clinical examination
Polypharmacy Among Home-Dwelling Older Adults: The Urgent Need for an Evidence-Based Medication Management Model.
Ageing populations with multiple chronic conditions challenge low-, middle-, and high-income countries. Older adults frequently depend on complex medication regimens and polypharmacy, both of which can lead to potentially devastating and debilitating medication-related problems and to subsequent far-reaching public health, social, and economic effects. This perspectives article provides an overview of the current state of medication management, reflects on its relevance among polymedicated home-dwelling older adults living with multiple chronic conditions, and proposes patient-centered approaches for optimizing medication management and preventing medication-related problems
Co-expression of functional human Heme Oxygenase 1, Ecto-5'-Nucleotidase and ecto-nucleoside triphosphate diphosphohydrolase-1 by "self-cleaving" 2A peptide system
We developed an F2A-based multicistronic system to evaluate functional effects of co-expression of three proteins important for xenotransplantation: heme oxygenase 1 (HO1), ecto-5'-nucleotidase (E5NT) and ecto-nucleoside triphosphate diphosphohydrolase-1 (ENTPD1). The tricistronic p2A plasmid that we constructed was able to efficiently drive concurrent expression of HO1, E5NT and ENTPD1 in HEK293T cells. All three overexpressed proteins possessed relevant enzymatic activities, while addition of furin site interfered with protein expression and activity. We conclude that our tricistronic p2A construct is effective and optimal to test the combined protective effects of HO1, E5NT and ENTPD1 against xeno-rejection mechanisms
Applicability of the kp method to modeling of InAs/GaSb short-period superlattices
We investigate the long-standing controversy surrounding modeling of the electronic spectra of InAs/GaSb short-period superlattices (SPSLs). Most commonly, such modeling for semiconductor heterostructures is based on the kp method. However, this method has so far failed to predict the band structure for type-II InAs/GaSb SPSLs. Instead, it has systematically overestimated the energy gap between the electron and heavy-hole minibands, which led to the suggestion that the kp method is inadequate for these heterostructures. Our results show that the physical origin of the discrepancy between modeling and experimental results may be the graded and asymmetric InAs/GaSb interface profile. We have performed band-structure modeling within the kp method using a realistic interface profile based on experimental observations. Our calculations show good agreement with experimental data, both from our own measurements and from the published literature. © 2009 The American Physical Society
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