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1.
Ecol Food Nutr ; 61(1): 1-19, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33908326

RESUMEN

Despite Rwanda's impressive economic success over the last decade, household food insecurity persists, particularly in rural areas. Empirical evidence is therefore deemed necessary to inform policies addressing food insecurity, hunger and poverty in general. This study examines household food security and its determinants in the rural areas of Southern and Northern provinces of Rwanda. Using cross-sectional data collected from 534 farming households, we estimated household food security status by Food Consumption Score (FCS) and Food Insecurity Experience Scale (FIES) and applied ordered Probit model to identify drivers of household food security. The results indicate that a significant proportion (74.4%) of households had an acceptable FCS, but 36.52% of the farming households experienced moderate and severe food insecurity when assessed with FIES. Ownership of livestock was identified as a key determinant of food security using both metrics, which affirms the importance of combating hunger and food insecurity in Rwanda through their 'one cow per household policy' and recommends that this policy be strengthened.


Asunto(s)
Composición Familiar , Abastecimiento de Alimentos , Agricultura , Estudios Transversales , Seguridad Alimentaria , Humanos , Rwanda
2.
Nanotechnology ; 26(26): 265303, 2015 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-26062896

RESUMEN

The thermal annealing of zinc precursors to form suitable seed layers for the growth of ZnO nanowires is common. However, the process is relatively long and involves high temperatures which limit substrate choice. In this study the use of a low temperature, ultra-violet (UV) exposure is demonstrated for photodecomposition of zinc acetate precursors to form suitable seed layers. Comparisons are made between ZnO nanowire growth performed on seed layers produced through thermal annealing and exposure to UV. The dependence of growth density and nanowire diameter on UV exposure time is investigated. Growth quality is confirmed with energy dispersive x-ray (EDX) and x-ray diffraction analyses. The chemical composition of the exposed layers is investigated with EDX and x-ray photoelectron spectroscopy (XPS). Atomic force microscopy (AFM) is utilized to investigate morphological changes with respect to UV exposure. The diameter and density of the resultant growth was found to be strongly dependent on the UV exposure time. UV exposure times of only 25-30 s led to maximum density of growth and minimum diameter, significantly faster than thermal annealing. EDX, XPS and AFM analyses of the seed layers confirmed decomposition of the zinc precursor and morphological changes which influenced the growth.

3.
Nanotechnology ; 24(19): 195602, 2013 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-23579099

RESUMEN

In this study, the use of flexographic printing was investigated for low cost, high volume production of devices incorporating nanowires through the printing of zinc acetate precursors on a substrate used to form zinc oxide (ZnO) seeds for the growth of nanowires using a hydrothermal growth technique. The printing of precursors allows the selective area growth of ZnO nanowires, which has implications in high-yield production of devices incorporating ZnO nanowires. The work presented here achieved printed line widths of <60 µm with low edge distortion (<3 µm) using a printing plate with a line width of 50 µm. The hydrothermally grown ZnO nanowires show uniform density of growth over the printed area with nanowire diameters between 40 and 60 nm on both silicon and polyimide substrates. Energy-dispersive x-ray spectra showed contamination-free crystals with a 1:1 (zinc to oxygen) stoichiometry. Crystal orientation is along the c-axis with high quality crystalline structure shown using x-ray diffraction spectroscopy and high resolution transmission electron microscopy. A ZnO nanowire gas sensor, fabricated using the flexographic printing technique, is demonstrated. Such a printing-assisted fabrication offers low cost, high volume production of devices incorporating ZnO nanowires, ranging from gas sensors to field emission devices.

4.
Heliyon ; 9(12): e22724, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38107300

RESUMEN

Gender differences in productivity are one of the major obstacles impeding the development of agriculture in Africa and Nigerian particularly. With the Oaxaca-Blinder (OB) and exogenous switching treatment regression (ESTER) models, this study investigates the causes of the productivity differences among 360 sampled rice farmers in Nigeria as well as gender inequality in agricultural productivity. The findings showed that there is an inequalities between men and women, which contributes to a gender productivity gap of almost 29 % in favour of men. As a result, plots managed by women are 29 % less productive than plots handled by men. The analysis of the factors influencing gender variations in production reveals that the endowment component, which accounts for 15 % of the productivity gap, is significantly influenced by marital status, education, farm size, and access to market information. Similarly, the ESTER results show that the rice yield of FHHs would have decreased by 25.41 kg/ha (a 1.02 % reduction) if they had been assigned the same returns to the observed features of MHHs. This difference is significant at the 1 % level. Thus, the findings imply that the FHHs are not at a yield disadvantage when compared to the MHHs. Therefore, it can be said that there are gender productivity disparities in the Nigerian agricultural industry. As such, policy interventions aimed at empowering women must take these disparities into consideration as well as the causes that contribute to them. Overall, the results demonstrate that although policymakers and their development partners can use improved technologies to increase MHH and FHH yields, reducing the difference in market linkages is necessary to close the gender gap in rice productivity and provide FHHs with equal access to the market.

5.
Heliyon ; 7(3): e06433, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33763609

RESUMEN

This study estimated the effect of the adoption of soil and water conservation (SWC) on the productivity of 360 smallholder rice farmers in Southwest Nigeria. An endogenous switching regression model (ESRM) was employed to estimate the productivities of adopter and non-adopters of SWC. A doubly robust inverse-probability-weighted regression adjustment (IPWRA) was used as a credible remedy for potentially biased estimates of average treatment on the treated (ATT) and potential outcome mean (POM) of the endogenous treatment model. Significant variables, such as farmers' locations, gender, marital status, annual temperature, annual precipitation, log of fertiliser and membership in farm-based organisation (FBO), were factors influencing the adoption of SWC among smallholder rice farmers. Factors such as age, marital status, rice experience, farm size, formal education, access to extension and labour in man-days significantly influenced the rice productivity of smallholder farmers who adopted SWC technology, while location, marital status, rice experience, farm size, formal education, access to extension and labour in man-days were the determinants of rice productivity among smallholder farmers who did not adopt SWC technology. The result from the inverse-probability-weighted regression adjustment estimation indicates that the adoption of SWC technology to mitigate the adverse effects of climate change improves the productivity of rice in the study area. To ensure effective dissemination and the adoption of new conservation technologies, government and stakeholders in rice production could take the lead in promotion and dissemination in the initial stages and, in the process, create an enabling environment for the effective participation of other stakeholders in rice production.

6.
Heliyon ; 7(6): e07162, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34151036

RESUMEN

Non-farm employment in agrarian communities in developing countries has received a lot of attention. However, its role in implementing climate change adaptation strategies is rarely discussed. This study employs a cross-sectional data to examine whether rural households in Southwest Nigeria are increasing the extent of climate change adaptation practices through their participation in non-farm employment. To account for selectivity bias, the study used endogenous treatment effect for count data model (precisely Poisson) augmented with the inverse probability-weighted-regression-adjustment (IPWRA) estimator. Both estimators found that rural non-farm jobs increase smallholder farmers' adaptive capacities and that participants would have used less adaptation techniques if they had not participated in non-farm work. Efforts to boost rural development must provide more employment opportunities for farmers, particularly during the off-cropping time. This will help farmers improve their ability to adopt more climate change adaptation strategies and, consequently increase farm productivity.

7.
Heliyon ; 6(5): e04012, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32490238

RESUMEN

This study considers the presence of a gender gap in technical efficiency in Ghana's cocoa production sector. The two-stage double bootstrap data envelopment analysis (DEA) procedure was applied to estimate the bias-corrected technical efficiency scores for male and female cocoa farm managers. The results indicate that there is a potential for male and female cocoa farm managers to increase output without altering the quantities of inputs employed. Applying the extended version of the Blinder-Oaxaca (B-O) decomposition approach, the findings suggest that female plot managers are, on average, less technically efficient compared to their male counterparts. This gap could be linked to differences in their resource endowments. Nevertheless, there are still significant unobservable factors that contribute to the gender efficiency gap. A comprehensive decomposition examination indicates that differences in educational attainment, engagement in non-farm activities, and farm size may contribute to the unexplained technical efficiency gap. The study recommends that female-sensitive programmes that seek to encourage the participation of non-farm activities and provide access to education and land utilization are essential in reducing the gender gap in technical efficiency.

8.
Nucleic Acids Res ; 29(11): E54-4, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11376166

RESUMEN

The formation of DNA three-way junction (3WJ) structures has been utilised to develop a novel isothermal nucleic acid amplification assay (SMART) for the detection of specific DNA or RNA targets. The assay consists of two oligonucleotide probes that hybridise to a specific target sequence and, only then, to each other forming a 3WJ structure. One probe (template for the RNA signal) contains a non-functional single-stranded T7 RNA polymerase promoter sequence. This promoter sequence is made double-stranded (hence functional) by DNA polymerase, allowing T7 RNA polymerase to generate a target-dependent RNA signal which is measured by an enzyme-linked oligosorbent assay (ELOSA). The sequence of the RNA signal is always the same, regardless of the original target sequence. The SMART assay was successfully tested in model systems with several single-stranded synthetic targets, both DNA and RNA. The assay could also detect specific target sequences in both genomic DNA and total RNA from Escherichia coli. It was also possible to generate signal from E.coli samples without prior extraction of nucleic acid, showing that for some targets, sample purification may not be required. The assay is simple to perform and easily adaptable to different targets.


Asunto(s)
ADN/genética , Reacción en Cadena de la Polimerasa/métodos , ARN/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , ADN/química , Sondas de ADN , ADN Bacteriano/química , ADN Bacteriano/genética , Escherichia coli/genética , Humanos , Conformación de Ácido Nucleico , Oligonucleótidos/genética , ARN/química , ARN Bacteriano/química , ARN Bacteriano/genética
9.
J Clin Endocrinol Metab ; 55(3): 453-8, 1982 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6808005

RESUMEN

The gonadotropin secretory patterns of 22 sexually immature children were analyzed in detail to determine whether pulsatile secretion occurs before the onset of puberty. Eight endocrinologically normal children, 13 children with isolated GH deficiency, and 1 girl with 45X gonadal dysgenesis were divided into 2 groups according to bone age. Group A children had bone ages less than 10 yr, and group B had bone ages between 10-11.5 yr. Blood samples were drawn every 20 min for periods of 3-11 h during both the day and night; in addition, 12-h urine collections were made for gonadotropin determinations. Mean nocturnal concentrations of LH and FSH were significantly greater than daytime values in 8 of 15 and 5 of 15 children in group A and in 6 of 7 and 1 of 7 in group B, respectively. Nocturnal urinary excretion of LH and FSH was significantly greater in group A children. Eight children in group A, including 4 whose bone ages were less than 5 yr, and 4 group B children had discernible LH pulses. LH pulses were detected during the day and night in both groups. LH pulse amplitude was greater during the night in both groups, but was greatest in group B (A, 1.9 +/- 0.2 mIU/ml; B, 3.0 +/- 0.3 mIU/ml). In children who demonstrated pulsatile secretion, LH pulse frequency appeared to be similar during the day and night and was slightly faster in the older children (A, every 3 h; B, every 2 h). These studies demonstrated that LH is secreted in a pulsatile manner well before the onset of puberty. Furthermore, the gonadotropin secretory pattern characteristic of early puberty results from the amplification of an already existing circadian pattern of gonadotropin secretion.


Asunto(s)
Ritmo Circadiano , Hormona Luteinizante/metabolismo , Maduración Sexual , Niño , Preescolar , Femenino , Hormona Folículo Estimulante/metabolismo , Hormona Liberadora de Gonadotropina , Humanos , Masculino , Pubertad , Síndrome de Turner/metabolismo
10.
Arch Dermatol ; 114(10): 1456-62, 1978 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-718180

RESUMEN

A nationwide study of the practice activities of dermatologists reports that dermatology is a predominantly outpatient specialty, with 97% of patient encounter occurring outside of the hospital. The average dermatologist cares for approximately 7,000 patients a year and functions almost exclusively as a specialist, with only 2.2% of his cases related to nondermatologic problems. The dermatologist performs a type of primary care, however, with seven out of ten patients being self-referred. Eighty-seven percent of dermatologic encounters can be categorized into 25 disease conditions. This study serves to increase the understanding of how the dermatologist cares for his patients.


Asunto(s)
Dermatología , Práctica Profesional , Adolescente , Adulto , Anciano , Atención Ambulatoria , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Administración de la Práctica Médica , Atención Primaria de Salud , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/terapia , Análisis y Desempeño de Tareas , Estados Unidos , Recursos Humanos
11.
Physician Exec ; 20(3): 8-11, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10161052

RESUMEN

The U.S. health care system is fundamentally changing. The pace of change is swift but will vary, depending on regional market forces and state legislative mandates. This complex change is leading to rapid market consolidation of providers and insurers into organizations called "integrated health care systems." There is, as yet, no proven role model that will guarantee success. The purpose of this article is two-fold: To help individuals who see an expanding role for themselves in integrated health care management decide if they have what it is going to take to be successful. To identify individual management training needs by use of a self-evaluation tool. Some of the needed skills can be enhanced by education and experience. However, some are personality and style characteristics that may not be changeable.


Asunto(s)
Atención Integral de Salud/organización & administración , Liderazgo , Sistemas Multiinstitucionales/organización & administración , Ejecutivos Médicos/normas , Reforma de la Atención de Salud , Relaciones Interinstitucionales , Competencia Profesional , Encuestas y Cuestionarios , Estados Unidos
12.
Physician Exec ; 17(2): 23-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-10160766

RESUMEN

In fall 1990, Witt Associates again catalogued the progress of physicians as they obtain management positions of increasing importance. The firm has conducted a continuing study of the position since 1979. The current survey of vice presidents of medical affairs/medical directors renders a candid portrait of the physician manager. The profile that emerges is a 53-year-old white male, working almost 50 hours a week in a full-time position, appointed by the hospital and reporting to the Chief Executive Officer. This individual is board certified and has major responsibilities for quality assurance, credentialing, risk management, and utilization review. His or her salary is into six figures.


Asunto(s)
Ejecutivos Médicos/estadística & datos numéricos , Salarios y Beneficios/estadística & datos numéricos , Empleo/estadística & datos numéricos , Capacidad de Camas en Hospitales , Perfil Laboral , Rol , Encuestas y Cuestionarios , Estados Unidos
13.
Physician Exec ; 21(1): 22-6, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10161140

RESUMEN

The recent rise in the number of physician executives in the health care industry vividly demonstrates that a genuinely new generation of physician executives is seeking to combine the sensitivity of their clinical skills with the business acumen that today's health care organizations need to prosper and grow. But physicians who are preparing themselves to be selected one day as chief executive officers by hospitals, integrated systems, and managed care organizations should understand that the CEO role is radically different from that of the CEO of a physician practice. The corporate CEO role requires the management of managers and responsiveness to the organization's board. Those who imagine that the corporate CEO role bears any resemblance to the autonomous, independent existence of the practitioner are certain to have a rough time.


Asunto(s)
Movilidad Laboral , Ejecutivos Médicos/estadística & datos numéricos , Recolección de Datos , Escolaridad , Femenino , Práctica de Grupo/organización & administración , Práctica de Grupo/tendencias , Humanos , Liderazgo , Masculino , Programas Controlados de Atención en Salud/organización & administración , Persona de Mediana Edad , Ejecutivos Médicos/economía , Ejecutivos Médicos/educación , Salarios y Beneficios , Integración de Sistemas , Estados Unidos
14.
Physician Exec ; 22(1): 53-5, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10161284

RESUMEN

A substantial percentage of the positions that open in medical management are filled through the use of recruitment firms. This is especially true of more senior positions, but it applies across the full spectrum of openings. If the working arrangement between the recruitment firm and the potential candidate is to be effective, certain key ingredients are necessary. The author interviewed a selection of principals of recruitment firms that operate extensively or exclusively in the medical management sector of executive recruitment. What she discovered about their "wish lists" for candidates' characteristics and levels of job hunting sophistication are summarized in the following statements.


Asunto(s)
Selección de Personal/métodos , Ejecutivos Médicos/normas , Selección de Profesión , Movilidad Laboral , Servicios Contratados , Solicitud de Empleo , Competencia Profesional , Estados Unidos
15.
Healthc Financ Manage ; 45(5): 117-23, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-10145424

RESUMEN

A more sophisticated healthcare industry, challenged by competition and payer demands, also looks for sophistication when filling its senior financial positions. Individuals with experience in managed care contract negotiations, knowledge of hospital-physician ventures, and superior planning and treasury management skills are increasingly sought by hospitals. Some organizations also may single out chief financial officers able to assume broader administrative duties, including chief executive officer positions. These are among the observations of a panel convened by HFMA to discuss recent trends in healthcare executive recruiting. Highlights of the session, moderated by HFMA President Richard L. Clarke, FHFMA, follow.


Asunto(s)
Administración Financiera de Hospitales , Administradores de Hospital/normas , Competencia Profesional , Empleo/tendencias , Selección de Personal/tendencias , Estados Unidos
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