1,736 research outputs found
Sectoral allocation by gender of Latin American workers over the liberalization period of the 1990s
No full textThe recent restructuring of Latin American economies has renewed interest in the effects of trade liberalization, on labor markets, and on the gender division of labor. The author does not attempt to establish casuality between economic reforms, and the types of jobs that men and women hold. Instead, she provides a detailed description of the trends in male, and female formal, and informal sector participation during the economic reform period in Argentina, Brazil, and Costa Rica. The author first compares the gender composition of the formal, informal wage, and self-employment sectors in a year before reforms (1988 for Argentina, 1989 for Brazil, and Costa Rica), and a year after reforms implementation (1997 for Argentina, 1995 for Brazil and Costa Rica). Although women continued to be more likely than men to work in the informal wage sector, there is no trend of"masculinization"or"feminization"of the informal sector, or any other. Instead, in Argentina men have overtaken women as the most prevalent workers in the informal wage sector, while in Brazil, the opposite has occurred (as men move into self-employment). In Costa Rica there have been no statistical, observable changes. The author then considers the distribution across sectors within each gender group, to identify whether men, and women are more likely to select different sectors in the post-reform period relative to the pre-reform period. Among both men, and women in all three countries (except Brazilian men), workers have become more likely to hold informal wage jobs, and less likely to hold formal sector jobs. Trends in human capital accumulation explain these changes for both men, and women, while changes in gender roles, primarily in homecare and marriage, do not seem to have an effect.Health Monitoring&Evaluation,Labor Policies,Population&Development,Public Health Promotion,Environmental Economics&Policies,Health Monitoring&Evaluation,Environmental Economics&Policies,Population&Development,Banks&Banking Reform,Work&Working Conditions
Why liberalization alone has not improved agricultural productivity in Zambia : the role of asset ownership and working capital constraints
No full textThe authors use a large panel data set from Zambia to examine factors that could explain the relatively lackluster performance of the country's agricultural sector after liberalization. Zambia's liberalization significantly opened the economy but failed to alter the structure of productionor help realize efficiency gains. They reach two main conclusions. First, not owning productive assets (in Zambia, draft animals and implements) limits improvements in agricultural productivity and household welfare. Owning oxen increases income directly, allows farmers to till their fields efficiently when rain is delayed, increases the area cultivated, and improves access to credit and fertilizer markets. Second, the authors reject the hypothesis that the application of fertilizer is unprofitable because of high input prices. Rather, fertilizer use appears to have declined because of constraints on supplies, which government intervention exacerbated instead of alleviating. (Extending the use of fertilizer to the many producers not currently using it would be profitable, but increasing the amount applied by the few producers who now have access to it would not be.) Policies to foster accumulation of the assets needed for agricultural production (including draft animals and implements) and to provide complementary public goods (education, credit, and good agricultural extension services) could greatly help reduce poverty and improve productivity.Economic Theory&Research,Environmental Economics&Policies,Labor Policies,Banks&Banking Reform,Agricultural Knowledge&Information Systems,Environmental Economics&Policies,Economic Theory&Research,Banks&Banking Reform,Agricultural Knowledge&Information Systems,Agricultural Research
Modeling Surface Brightness of the HH 901 Jets in the Carina Nebula
No full textabstract: The purpose of this thesis is to accurately simulate the surface brightness in various spectral emission lines of the HH 901 jets in the Mystic Mountain Formation of the Carina Nebula. To accomplish this goal, we gathered relevant spectral emission line data for [Fe II] 12660 Å, Hα 6563 Å, and [S II] 6720 Å to compare with Hubble Space Telescope observations of the HH 901 jets presented in Reiter et al. (2016). We derived the emissivities for these lines from the spectral synthesis code Cloudy by Ferland et al. (2017). In addition, we used WENO simulations of density, temperature, and radiative cooling to model the jet. We found that the computed surface brightness values agreed with most of the observational surface brightness values. Thus, the 3D cylindrically symmetric simulations of surface brightness using the WENO code and Cloudy spectral emission models are accurate for jets like HH 901. After detailing these agreements, we discuss the next steps for the project, like adding an external ambient wind and performing the simulations in full 3D
Canonical formalism for Lagrangians of maximal nonlocality
No full textA canonical formalism for Lagrangians of maximal nonlocality is established. The method is based on the familiar Legendre transformation to a new function, which can be derived from the maximally nonlocal Lagrangian. The corresponding canonical equations are derived through the standard procedure in local theory and appear much like those local ones, though the implication of the equations is largely expanded.Physics, MultidisciplinarySCI(E)中国科学引文数据库(CSCD)0ARTICLE5715-7224
A study on the cell mediated immunity of human cytomegalovirus infection in kidney transplant recipients
No full textCytomegalovirus (CMV) infection is a major complication after kidney transplantation. Despite antiviral therapy it contributes significantly to high morbidity. This study was aimed at (a) detecting· a CMV specific antigen pp65 in CMV -infected fibroblast cells and in leukocytes of kidney transplant recipients by flow cytometric assay (FCA) (b) determining the stimulation index (S.I.) of phytohaemagglutinin (PHA) and CMV-stimulated peripheral blood mononuclear cells (PBMC), (c) determining the levels of Th1- and Th-2 related cytokines in the supernatant of stimulated PBMC from kidney transplant recipients with and without active CMV infection (d) determining immunophenotyping of cells found in the peripheral blood of CMV -infected and CMV -uninfected kidney transplant recipients by flow cytometry using antibodies specific to CD2+ (pan T), CD3+ (mature T), CD4+ (T helper), CD8+ (T suppressor), CD26+(T activated), CDI6+/CDS6+ (NK cell), CDI9+(pan B), CDIS+ (granulocytes). Thirty-five patients with, and 44 without active CMV infections, as diagnosed by a CMV antigenemia assay (AA), were inducted into this study. FCA distinguished clearly between the infected and uninfected fibroblast cells. Regarding kidney transplant recipients, the FCA was positive when the number of AA positive cells was five or more per 5x10(4). Moreover, the percentage of antigenemia-positive cells by FCA correlated well with symptomatic CMV infections. After PHA and CMV stimulation of PBMC from patients, S.I. was determined by radioactive thymidine uptake while the production of Th1-type cytokines [interleukin-2 (iL-2), interferon-y (IFN-y) and tumor necrosis factor-a (TNFex)] and Th2-type cytokines (IL-4, IL-1O) were measured by ELISA. PBMC of patients with active CMV infection showed significantly lower S.I. values than patients without an ongoing CMV infection (p<O.OOO1). Levels of Th2- type cytokines in CMV -infected and uninfected kidney recipients were similar;however, the levels of the Th1-type cytokines were significantly lower in CMV -infected patients (p<O.O5). Low levels of Th1-type cytokines seem to correlate well with active CMV infection in kidney recipients. The percentage of CD3+ immunocompetent T lymphocytes and CD4+ T lymphocytes were consistently higher in kidney transplant recipients without an active CMV infection than in the group of recipients with an active CMV infection. These differences were statistically significant in the case of CD3+ (p<O.O5) and CD4+ (p<O.OO5). On the other hand the difference in percentage CD2+, CD8+, CD16++CD56+, CD19+, CD15+ cells were statistically insignificant. Therefore, these data suggest that active CMV infection in kidney transplant recipients is associated with a significant alteration in the lymphocyte proliferative responses, the levels of Th1-type cytokines (IFN-y, TNF-ex, IL-2), and the percentage of CD3+, CD4+ when compared to kidney transplant recipients without active CMV infection
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No full textSmoothened (Smo) inhibition by Patched (Ptch) is central to Hedgehog (Hh) signaling. Ptch, a proton driven antiporter, is required for Smo inhibition via an unknown mechanism. Hh ligand binding to Ptch reverses this inhibition and activated Smo initiates the Hh response. To determine whether Ptch inhibits Smo strictly in the same cell or also mediates non-cell-autonomous Smo inhibition, we generated genetically mosaic neuralized embryoid bodies (nEBs) from mouse embryonic stem cells (mESCs). These experiments utilized novel mESC lines in which Ptch1, Ptch2, Smo, Shh and 7dhcr were inactivated via gene editing in multiple combinations, allowing us to measure non-cell autonomous interactions between cells with differing Ptch1/2 status. In several independent assays, the Hh response was repressed by Ptch1/2 in nearby cells. When 7dhcr was targeted, cells displayed elevated non-cell autonomous inhibition. These findings support a model in which Ptch1/2 mediate secretion of a Smo-inhibitory cholesterol precursor
The Case of Re-plex: Wastewater to Building material: Life Cycle Assessment on the use of Re-plex as interior finishing material
No full textWith the increasing focus from policymakers to a circular economy, assessing the environmental impacts of circular products is becoming more important. In this thesis a Life Cycle Assessment of the new circular composite Re-plex is performed. The Re-plex can be used as building material. Re-plex is produced from Kaumera Nereda® Gum recovered from Nereda® wastewater sludge, and Recell® cellulose recovered from wastewater. Re-plex is still in the developmental phase, this LCA is performed to aid engineers to reduce the environmental impacts of the Re-plex composite. A comparative LCA is performed in which the current Re-plex production is compared to Fire-retardant Medium Density Fibreboard (FR-MDF) with the ILCD impact assessment family. The functional unit is 1 year of 1m2 use of interior finishing material.The Re-plex has a better characterisation result in the impact category; Human Health (HH), respiratory effects, inorganics. The FR-MDF has better characterisation results in the impact categories; Climate change; Ecosystem Quality (EQ), acidification; EQ, freshwater ecotoxicity; EQ, freshwater eutrophication; EQ ionizing radiation; EQ, marine eutrophication; EQ, marine eutrophication; Human Health (HH), carcinogenic effects; HH, ionizing radiation; HH, non-carcinogenic effects; HH, ozone layer depletion; HH, photochemical ozone creation; Resources (RS), land use; and RS, mineral, fossils and renewables. Scenarios are developed to improve the environmental performance of the Re-plex production. Increasing the amount of cellulose in Re-plex does not seem to improve the environmental performance. Three scenarios do improve the environmental performance; Replacing citric acid by succinic acid; improving the energy efficiency; and drying the Kaumera Gum before transport. These three improvements are combined in the new Re-plex scenario. The improved scenario has better characterisation results than FR-MDF in the ten impact categories; Climate change; EQ, acidification; EQ, freshwater ecotoxicity; EQ, freshwater eutrophication; EQ, marine eutrophication; EQ, marine eutrophication; HH, carcinogenic effects; HH, non-carcinogenic effects; HH, photochemical ozone creation; and HH, respiratory effects, inorganics. FR-MDF scores better in the five impact categories; EQ ionizing radiation; HH, ionizing radiation; HH, ozone layer depletion; RS, land use; and RS, mineral, fossils and renewables. Engineers working on Re-plex are advised to change the use of citric acid to a better environmentally performing material. The environmental benefit of changing this material will add more value to a Re-plex product than the lower price when using citric acid. Further, the focus should be on improving the energy efficiency of Re-plex production and realising a lifetime of Re-plex of 32 years, similar to MDF. If these improvements can be realised, Re-plex has a better environmental performance than FR-MDF.Industrial Ecolog
THE INTRIGUING GIANT BOW SHOCKS NEAR HH 1311
No full textUsing the High Dispersion Spectrograph (HDS) at the Subaru Telescope, echelle spectra of two giant arcs, i.e., nebulosities Cw and L associated with HH 131 in Orion are presented. Typical emission lines of Herbig-Haro (HH) objects have been detected toward nebulosity Cw with the broadband filter KV 408. With the low-dispersion spectrograph at the National Astronomical Observatories (NAO) 2.16m telescope, spectra of nebulosities C, L, and K are obtained, which also show strong [S ii] k6717/k6731, H, and [N ii] k6583 emission lines. Position-velocity distributions of Cw and L are analyzed from the long-slit spectra observed with the HDS H narrowband filter. The fastest radial velocity of Cw is Vr 18:0 km s1. When the flow at L goes to the south, it slows down. The fastest radial velocity of L has been observed at 45.0 km s1, and the slowest value is about 18.3 km s1; the radial velocity gradient is about 200 km s1 pc1. The similarity of the fastest radial velocity of Cw to the slowest value of L and their positional connection indicate that they are physically associated. There is a tendency for the entire flow to become less excited and less ionized when going further to the south (i.e., from nebulosities K to L and C), where themost extended (and presumably evolved) objects are seen. The electron densities of all the observed nebulosities are low (ne 102 cm3). Double-peaked kinematic signatures have been found in Cw from its [N ii] k6583 profiles, while the observed H profiles of Cw are almost symmetric. Bow shock models appear to agree with the observed position-velocity diagrams of the [N ii] spectra better than H spectra, and a bow shock with its wing, apex, and postshock has been possibly revealed near Cw from the [N ii] emission. With the suggestion that these arcs are HH shocks possibly ejected out of the Orion A molecular cloud by an uncertain source, their spectra show low to intermediate excitation from their diagnostic line ratios
Exploring effects of introducing a ban on handheld phone use for cyclists – Pre-post results from the Netherlands and Denmark
No full textCyclists’ phone use can cause distractions and impose risks towards traffic safety. To prevent phone-related distractions, the Netherlands introduced a ban on handheld (HH) phone use for cyclists in July 2019. The effects of traffic rules on phone use and their underlying mechanisms are, however, uncertain. Comparing survey results from the Netherlands before (N = 553) and after (N = 484) the ban, using Denmark (before N = 568, after N = 519) as comparison group, this study explores whether introducing a ban is associated with changes in phone use, traffic rule beliefs, perceived risk, sense of guilt, and perceived annoyance. Comparison of phone function use before and after the Dutch ban revealed a significant decrease in the proportion using HH phone for conversation, while there was no change for other functions. In Denmark, proportions remained stable for all functions. Changes in the Netherlands possibly correspond to specific phone functions characteristics, e.g., how effortless one can pause and resume the function. The results additionally identified an increase in correct traffic rule identification, sense of guilt for HH phone use, and perceived annoyance, while there was no significant change in perceived risk of HH phone use. The study found that banning HH phone use was associated with increase in correct rule identification, but only to limited changes in HH phone use. Banning HH phone use might have greater effects in changing behaviours over time as a result of social mechanisms related to changes in sense of guilt and perceived annoyance.Transport and Plannin
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