The Rockefeller Foundations International Health Board and the Attempt to Eradicate Yellow Fever

Beginning in 1914, the Rockefeller Foundation's International Health Commission (which became the International Health Board in 1916 and the International Health Division in 1927) committed itself to the project of eradicating yellow fever. Its efforts were modeled on the sanitary techniques deployed by US sanitarians in Havana in 1901 and, more importantly, during the construction of the Panama Canal between 1904 and 1914, with mosquito control preeminent among them. William C. Gorgas, who led these campaigns and then came to work for the Rockefeller Foundation, argued for a key center approach to yellow fever eradication that targeted the remaining urban endemic foci of infection, with the assumption that once these seed beds of the disease were eliminated, yellow fever would fade from the planet. But as the IHB conducted campaigns in South America, Central America, and West Africa during the late 1910s and 1920s, they discovered that yellow fever's ecology and epidemiology were more complicated than they had assumed, and that a "key center" approach would not work to eradicate the disease. By the 1930s, and particularly with Fred Soper's discovery of sylvan or jungle yellow fever, the Rockefeller Foundation gave up on their eradicationist dream

Multidisciplinary analysis of actively controlled large flexible spacecraft

The control of Flexible Structures (COFS) program has supported the development of an analysis capability at the Langley Research Center called the Integrated Multidisciplinary Analysis Tool (IMAT) which provides an efficient data storage and transfer capability among commercial computer codes to aid in the dynamic analysis of actively controlled structures. IMAT is a system of computer programs which transfers Computer-Aided-Design (CAD) configurations, structural finite element models, material property and stress information, structural and rigid-body dynamic model information, and linear system matrices for control law formulation among various commercial applications programs through a common database. Although general in its formulation, IMAT was developed specifically to aid in the evaluation of the structures. A description of the IMAT system and results of an application of the system are given

Constraints on Cosmology and Gravity from the Dynamics of Voids

The Universe is mostly composed of large and relatively empty domains known as cosmic voids, whereas its matter content is predominantly distributed along their boundaries. The remaining material inside them, either dark or luminous matter, is attracted to these boundaries and causes voids to expand faster and to grow emptier over time. Using the distribution of galaxies centered on voids identified in the Sloan Digital Sky Survey and adopting minimal assumptions on the statistical motion of these galaxies, we constrain the average matter content $\Omega_\mathrm{m}=0.281\pm0.031$ in the Universe today, as well as the linear growth rate of structure $f/b=0.417\pm0.089$ at median redshift $\bar{z}=0.57$, where $b$ is the galaxy bias ($68\%$ C.L.). These values originate from a percent-level measurement of the anisotropic distortion in the void-galaxy cross-correlation function, $\varepsilon = 1.003\pm0.012$, and are robust to consistency tests with bootstraps of the data and simulated mock catalogs within an additional systematic uncertainty of half that size. They surpass (and are complementary to) existing constraints by unlocking cosmological information on smaller scales through an accurate model of nonlinear clustering and dynamics in void environments. As such, our analysis furnishes a powerful probe of deviations from Einstein's general relativity in the low-density regime which has largely remained untested so far. We find no evidence for such deviations in the data at hand.Comment: 11 pages, 7 figures. Reflects published version in PRL including Supplemental Materia

Estimation of fiber diameters in the spinal dorsal columns from clinical data

Lack of human morphometric data regarding the largest nerve fibers in the dorsal columns (DCs) of the spinal cord has lead to the estimation of the diameters of these fibers from clinical data retrieved from patients with a new spinal cord stimulation (SCS) system. These patients indicated the perception threshold of stimulation induced paresthesia in various body segments, while the stimulation amplitude was increased. The fiber diameters were calculated with a computer model, developed to calculate the effects of SCS on spinal nerve fibers. This computer model consists of two parts: (1) a three-dimensional (3-D) volume conductor model of a spinal cord segment in which the potential distribution due to electrical stimulation is calculated and (2) an electrical equivalent cable model of myelinated nerve fiber, which uses the calculated potential field to determine the threshold stimulus needed for activation. It is shown that the largest fibers in the medial DCs are significantly smaller than the largest fibers in the lateral parts. This finding is in accordance with the fiber distribution in cat, derived from the corresponding propagation velocities. Moreover, it is shown that the mediolateral increase in fiber diameter is mainly confined to the lateral parts of the DCs. Implementation of this mediolateral fiber diameter distribution of the DCs in the computer model enables the prediction of the recruitment order of dermatomal paresthesias following increasing electrical stimulation amplitud

Perceived Impact of the Youth Enterprise Development Fund on the Youth Towards the Establishment of Small Scale Rural Enterprises in Turbo Division, Uasin-gishu County, Kenya

The inception of the Youth Enterprise Development Fund has seen the rise of youth groups in rural areas. This paper is thus aimed at understanding the impact of the fund towards the youth establishment of small scale enterprises in Turbo Division. A descriptive research design was used in this paper. Data was collected using focused group discussion and self-administered questionnaires thus they were administered to the selected youth groups found in selected parts of the Turbo Division. Purposive technique was used in the specific youth of aged bracket 18 year to 35 years. Further, purposive and stratified sampling techniques were used in targeted youth groups. The sample size used was 147 drawn from Turbo Division. The salient findings of the study are that indeed the youth joined the small scale enterprises to obtain benefits through collaborative efforts, to gain and obtain skills and experiences, obtaining start-up capital and finally due to the unemployment. Moreover, impact made by the fund on individual life included; promoting togetherness, promoting income and sustained livelihoods thus improved economic statues, and eventually enhanced skills and experience that led to acquiring of more skills by joining polytechnics. Furthermore the fund had enhanced group development and participation. It is recommended that there should be enhanced youth group sustainability towards proper utilization of the fund

Increased surface expression of CD18 and CD11b in leukocytes after tourniquet ischemia during elective hand surgery

The surface expression of β2-integrins was investigated in leukocytes from patients undergoing ischemia induced by tourniquet application for elective hand surgery. Blood samples were obtained before initiation, at the end of ischemia, and after 15 minutes of reperfusion from ischemic and contralateral arms of five patients. Comparable expression of CD18, CD11a, CD11b, and CD11c could be detected by immunofluorescence in leukocytes from samples drawn from either arm before tourniquet application. In contrast, a significant increase in the expression of CD18 was detectable in monocytes, granulocytes, and lymphocytes from the ischemic arm compared with that in the nonischemic contralateral control, at the end of the ischemia time (80 ± 16 minutes). A significantly increased expression of CD11b, but not CD11a or CD11c, determinants was also observed in granulocytes and monocytes. Concomitantly, a significant reduction in the percentages of granulocytes in samples from ischemic areas was detectable. After 15 minutes of reperfusion, differences in the expression of these adhesion molecules were no longer significant. The expression of the genes encoding interleukins IL-1α, IL-1β, and IL-6 and tumor necrosis factor alpha (TNFα) proinflammatory cytokines was also studied by reverse polymerase chain reaction (rPCR) in peripheral blood mononuclear cells (PBMCs) obtained from the same samples in three patients. IL-1β or IL-6 gene expression was never observed. Expression of IL-1α and TNFα genes, as detected in two patients, was not related with induction of ischemia. However, in these patients expression of one or both these genes was observed in samples derived from the ischemic but not the control arm after 15 minutes of reperfusion. These data document that overexpression of adhesion molecules and sequestration of leukocytes take place following short ischemia times, as routinely applied clinically for minor surgical procedure

Nanophase Carbonates on Mars: Does Evolved Gas Analysis of Nanophase Carbonates Reveal a Large Organic Carbon Budget in Near-Surface Martian Materials?

Evolved Gas Analysis (EGA), which involves heating a sample and monitoring the gases released, has been performed on Mars by the Viking gas chromatography/mass spectrometry instruments, the Thermal and Evolved Gas Analyzer (TEGA) on the Phoenix lander, and the Sample Analysis at Mars (SAM) instrument on the Mars Science Laboratory. All of these instruments detected CO2 released during sample analysis at abundances of approx. 0.1 to 5 wt% assuming a carbonate source. The source of the CO2 can be constrained by evaluating the temperature of the gas release, a capability of both the TEGA and SAM instruments. The samples analyzed by SAM show that the majority of the CO2 is released below 400C, much lower than traditional carbonate decomposition temperatures which can be as low as 400C for some siderites, with magnesites and calcites decomposing at even higher temperatures. In addition to mineralogy, decomposition temperature can depend on particle size (among other factors). If carbonates formed on Mars under low temperature and relative humidity conditions, the resulting small particle size (nanophase) carbonates could have low decomposition temperatures. We have found that calcite can be synthesized by exposing CaO to water vapor and CO2 and that the resulting mineral has an EGA peak of approx. 550C for CO2, which is about 200C lower than for other calcites. Work is ongoing to produce Fe and Mg-bearing carbonates using the same process. Current results suggest that nanophase calcium carbonates cannot explain the CO2 released from martian samples. If the decomposition temperatures of Mg and Fe-bearing nanophase carbonates are not significantly lower than 400C, other candidate sources include oxalates and carboxylated organic molecules. If present, the abundance of organic carbon in these samples could be greater than 0.1 wt % (1000s of ppm), a signficant departure from the paradigm of the organic-poor Mars based on Viking results

Estudio sobre la salud mental y la calidad de vida de un grupo de cuidadores de personas con demencia y un grupo control en Cali, Colombia

Dementia caregivers are at risk for stress, depression, and a multitude of negative health outcomes, yet little research has examined the extent of these issues in caregivers from Latin America. The purpose of this study was to compare the mental health and health-related quality of life (HRQOL) of dementia caregivers to healthy controls in Cali, Colombia. Ninety dementia caregivers and 51 healthy controls completed measures of depression, satisfaction with life, stress, and HRQOL. Although it was hypothesized that dementia caregivers would report lower levels of mental health and HRQOL than controls, caregivers only reported higher depression levels. This finding suggests that dementia caregivers in this region, even when they have access to health care, are in need of mental health services and other caregiving resources. Such interventions would likely improve the mental health of caregivers and quality of care that caregivers are able to provide for individuals facing dementia.A pesar de que los cuidadores de personas con demencia están en riesgo de sufrir estrés, depresión y múltiples consecuencias negativas para la salud, se han realizado pocos estudios que hayan investigado el alcance de estos problemas en cuidadores de América Latina. El propósito de este estudio fue comparar la salud mental y la calidad de vida relacionada con la salud (CVRS) de un grupo de cuidadores de personas con demencia con un grupo de personas sanas de Cali, Colombia. Noventa cuidadores de personas con demencia y 51 personas sanas completaron una serie de cuestionarios que medía depresión, satisfacción con la vida, estrés y CVRS. A pesar de que se planteó la hipótesis de que los cuidadores de personas con demencia obtendrían niveles más bajos de salud mental y CVRS en comparación con el grupo de personas sanas, los cuidadores sólo reportaron mayores índices de depresión. Estos resultados sugieren que los cuidadores de demencia de esta región, a pesar tener acceso a los servicios de salud, necesitan servicios de salud mental y otros recursos de cuidado. Este tipo de ayudas e intervenciones probablemente ayudarían a mejorar su salud mental y la calidad de cuidado que pueden ofrecer a las personas que sufren demencia