80 research outputs found
Heterologous vaccine regimen: stakeholder acceptance and implementation considerations
Heterologous vaccine regimens deliver antigens through different vaccine components or vector types at sequential time points. Clinical development shows promising results and several candidates may be progressing to licensure in the coming years. This study aimed at exploring future acceptance and uptake of such regimens (also called heterologous prime-boost) and to identify implementation-associated benefits and challenges. Survey tools were developed based on findings from a previous literature search shared with the study team, and exploratory interviews with global stakeholders. An online survey and key informant interviews in six countries were conducted with stakeholders at national and sub-national level, including policy-makers, regulators and implementers. The interview guide and the online survey covered: (a) awareness of, and knowledge about, heterologous vaccine regimens; (b) rating of regimenassociated perceived benefits and challenges; (c) anticipation of possible challenges in relation to four hypothetical introduction scenarios; (d) potential acceptance benefits and challenges at the policy, health facility and recipient level. Sixty-two interviews were conducted at national level. The online survey was completed by 50 participants. Across the four introduction scenarios, respondents considered the highest potential for the introduction of heterologous regimens for immunoprophylaxis was among adolescents/ adults for diseases against which no vaccines are currently available. Most reservations were related to logistics, record keeping, and recipient compliance. Adding a new heterologous vaccine regimen to the routine immunization calendar for children was considered feasible if it could generate an increased and longer-term immune response. Introduction in preparation of or following a disease outbreak was considered less favourably, with respondents stressing the difficulty of logistics in emergency situations, and the potential lag in the onset of protection. The recent approval of the first heterologous vaccine regimen for the prevention of Ebola Virus Disease will soon bring new light to the topic
Effects of a four-year health systems intervention on the use of maternal and infant health services: results from a programme evaluation in two districts of rural Chad
BACKGROUND: Attendance of maternal and infant care services in rural Chad are consistently low. Our study aimed to assess the use of antenatal (ANC) and postnatal care (PNC) services, health facility delivery and infant health services after 4 years of a health systems intervention for improving the infrastructure, supplies, training and sensitization for maternal and infant health in two districts of rural Chad. METHODS: Data from a repeated cross-sectional household survey conducted in Yao and Danamadji in 2015 and in 2018 were analyzed. A stratified two-stage cluster sampling methodology was applied to achieve a representative sample of the rural settled and mobile population groups in the study area. A generalized linear model was applied to determine the health care utilization rates. Multivariate regression models were used to assess the association between the programme intervention and utilization outcomes of selected maternal and infant health services. RESULTS: Complete datasets were available for 1284 households at baseline. The endline analysis included 1175 households with complete survey data. The use of at least one ANC amongst pregnant women increased in both settled communities (from 80% in 2015 to 90% in 2018) and amongst mobile pastoralist communities (from 48% in 2015 to 56% in 2018). The rate of home delivery among settled communities and mobile pastoralists changed little between baseline and endline and remained high for both population groups. Individuals that were covered by the health systems intervention were however significantly more likely to attend ANC and less likely to give birth at home. PNC services only showed improvements amongst the settled communities (of 30%). Infants' reported health outcomes and vaccination coverage considerably improved; the latter especially among mobile pastoralist (from 15% in 2015 to 84% in 2018). CONCLUSION: A combination of health systems strengthening interventions was associated with an increased use of certain maternal and infant health services. However, to facilitate equitable access to and use of health care services in particular in times of increased vulnerability and by certain population groups in hard-to-reach areas, reinforced health education and culturally adapted communication strategies, including gender-specific messaging will be needed over a sustained period
Erratum to: Complementary school garden, nutrition, water, sanitation and hygiene interventions to improve childrenâs nutrition and health status in Burkina Faso and Nepal: a study protocol
Towards Landslide Predictions: Two Case Studies
In a previous work [Helmstetter, 2003], we have proposed a simple physical
model to explain the accelerating displacements preceding some catastrophic
landslides, based on a slider-block model with a state and velocity dependent
friction law. This model predicts two regimes of sliding, stable and unstable
leading to a critical finite-time singularity. This model was calibrated
quantitatively to the displacement and velocity data preceding two landslides,
Vaiont (Italian Alps) and La Clapi\`ere (French Alps), showing that the former
(resp. later) landslide is in the unstable (resp. stable) sliding regime. Here,
we test the predictive skills of the state-and-velocity-dependent model on
these two landslides, using a variety of techniques. For the Vaiont landslide,
our model provides good predictions of the critical time of failure up to 20
days before the collapse. Tests are also presented on the predictability of the
time of the change of regime for la Clapi\`ere landslide.Comment: 30 pages with 12 eps figure
Evidence-based policy making for health promotion to reduce the burden of non-communicable diseases in Moldova
Social learning as an underlying mechanism for sustainability in neglected communities: the Brazilian case of the Bucket Revolution project.
In neglected communities, waste and organic residues are not only a vector of several problems, like diseases and water pollution, but also a contributor to increasing forms of vulnerability and marginalization. At the same time, these communities also have presented innovative local initiatives and transformative learning about natural resources management that can be a vehicle for achieving more sustainable food systems. In the south of Brazil, community-based organic residue management has shown an extraordinary potential to improve food security and livelihoods for (~1600) community members of a vulnerable urban territory. In this context, the overall objective of this article is (a) To better understand what Social Learning (SL) processes related to successful organic residues management in neglected communities exist and (b) To identify what knowledge systems are created in one empirical case. The study case is based on a communitarian waste management project, the Bucket Revolution Project (BRP). The analytical framework builds upon social learning theory and its triple-loop process focusing on four specific phenomena. The applied mixed-methods approach was made in four steps: 1. a focus group to investigate collective community issues; 2. semi-structured interviews to investigate specific and individual issues in the context of the BRP; 3. social media analysis to better understand the BRP narratives; and finally 4. participant observation in community and institutional meetings. Mainly using MaxQda software and coding indicators of SL, the data show that "Diversity of knowledge integration" is the most identified SL indicator in the interviews (52%). For BRP, identity development, community conditions improvement, and environment understanding are three key components of the knowledge system enhanced through an underlying process of social learning. Furthermore, the study also shows that there are endogenous and exogenous social learning processes at work.On-line first
Acoustic fluidization and the extraordinary mobility of sturzstroms
with only a comparatively small vertical drop in height. Their extraordinary mobility appears to be a consequence of sustained fluid-like behavior during motion, which persists even for driving stresses well below those normally associated with granular flows. One mechanism that may explain this temporary increase in the mobility of rock debris is acoustic fluidization; where transient, high-frequency pressure fluctuations, generated during the initial collapse and subsequent flow of a mass of rock debris, may locally relieve overburden stresses in the rock mass and thus reduce the frictional resistance to slip between fragments. In this paper we develop the acoustic fluidization model for the mechanics of sturzstroms and discuss the conditions under which this process may sustain fluid-like flow of large rock avalanches at low driving stresses. INDEX TERMS: 182
GROWTH OF PEJIBAYE ( Bactris gasipaes Kunth) SEEDLINGS USING RESIDUE OF SAND MINING AS PART OF SUBSTRATES
O objetivo deste trabalho foi avaliar o crescimento de mudas de
pupunheira quando utilizado o res\uedduo fino de minera\ue7\ue3o
de areia na composi\ue7\ue3o de substratos. O experimento constou
de cinco tratamentos, sendo quatro composi\ue7\uf5es de diferentes
propor\ue7\uf5es de res\uedduo de minera\ue7\ue3o de areia e
casca de arroz carbonizada: 1:0; 3:1; 1:1; 1:3 e um substrato
padr\ue3o composto por latossolo amarelo podz\uf3lico \ue1lico e
esterco de b\ufafalo curtido, na propor\ue7\ue3o 3:1. Utilizou-se
o delineamento experimental de blocos ao acaso com cinco
repeti\ue7\uf5es e 10 mudas por parcela. Repicou-se uma
pl\ue2ntula de pupunheira por recipiente (sacos pl\ue1sticos de
polietileno preto de 8 x 20 cm, volume 1,1 L), os quais foram
preenchidos com os diferentes substratos. Foram determinadas
mensalmente as vari\ue1veis di\ue2metro do coleto, altura da haste,
n\ufamero de folhas e taxa de crescimento relativo e, ap\uf3s 180
dias da repicagem, os valores SPAD (Soil and Plant Analysis
Development), din \ue2mica da assimila\ue7\ue3o de CO2, da
transpira\ue7\ue3o e da condutividade estom\ue1tica. O
res\uedduo de minera\ue7\ue3o de areia puro como substrato
n\ue3o proporcionou mudas de qualidade, visto que esse material
apresenta alta densidade e baixa granulometria. Seu uso pode ser
indicado como um dos componentes de substratos, pois as plantas que
cresceram nas misturas de res\uedduo e casca de arroz carbonizada
apresentaram resultados semelhantes ao do considerado padr\ue3o.The objective of this study was to evaluate the growth of peach palm
seedlings using fine residue of sand mining as part of substrates. The
experiment comprised five treatments, four containing different ratios
of sand mining residue to carbonized rice husk: 1:0; 3:1; 1:1; 1:3, and
one composed of alic podzolic yellow latosol and buffalo manure in a
3:1 ratio, used as the standard substrate. Treatments were arranged in
randomized blocks with five replications and 10 seedlings each. One
peach palm seedling was transplanted per container, which consisted of
black, 8x20 cm, 1.1 L PE bags filled with different substrates.
Diameter of stem, plantlet height, number of leaves and relative growth
rate were recorded monthly and 180 days after their transplanting, SPAD
values, dynamics of CO2 assimilation, transpiration and stomatal
conductance. The use of unmixed residue of sand mining as substrate did
not produce quality seedlings, since that substance has high density
and poor particle size. It can be used as part of substrates though,
for plants grown in the mixtures of residue and carbonized rice husk
showed similar results to those grown in the standard substrate
Response of the photosynthetic apparatus to a flowering-inductive period by water stress in Citrus
The photosynthetic responses to a flowering-inductive water-stress period and recovery were studied and compared in two Citrus species. Under greenhouse conditions, Fino lemon and Owari satsuma trees were subjected to moderate (-2 MPa at predawn) and severe (-3 MPa) water stress levels and were re-watered after 60 days. Vegetative growth was inhibited during the stress assays, and strong defoliation levels were reported, especially in Fino lemon. In both species, bud sprouting was induced after re-watering. Flowers and vegetative shoots developed in Owari satsuma after a drought period, and the development was independent of the stress level. In Fino lemon, vegetative shoots and flowers were primarily formed after moderate and severe stress, respectively. The photosynthetic rate and stomatal conductance were reduced by water stress, and a marked increase in water-use efficiency at the moderate water deficit level was observed. Nevertheless, the photosynthetic apparatus was not damaged, since the maximum quantum yield, photosynthetic pigment concentrations and Rubisco level and activity did not change. Furthermore, the measured malonyldialdehyde (MDA) and peroxidase activity indicated that oxidative stress was not specifically triggered by water stress in our study. Therefore, the gas exchange, fluorescence and biochemical parameters suggested that diffusional limitations to photosynthesis predominated in both of the studied Citrus species, and explained the rapid recovery of the photosynthetic parameters after rehydration. The net CO 2 fixation rate and stomatal conductance were recovered within 24 h in Fino lemon, whereas 3 days were required in Owari satsuma. This suggests the presence of some metabolic limitations in the latter species. Furthermore, the sensibility of the defoliation rates, the accumulation of proline and the stomatal behaviour in response to water stress indicated a higher drought tolerance of Fino lemon, according to its better acclimation to hot climates. © 2011 Springer-Verlag.The authors thank Dr. J. Moreno and co-workers from the Departamento de Bioquimica of the Universidad de Valencia for his help and support in the Rubisco assays, and Dr. F. Fornes, Dr. A. Calatayud and Dr. E. Primo-Millo for the critical review of the manuscript. This work was funded by the Universitat Politecnica de Valencia, Spain (Ayudas para primeros proyectos de investigacion PAID06-06).Ăvila ResĂ©ndiz, C.; Guardiola Barcena, JL.; GonzĂĄlez Nebauer, S. (2012). Response of the photosynthetic apparatus to a flowering-inductive period by water stress in Citrus. Trees - Structure and Function. 26(3):833-840. https://doi.org/10.1007/s00468-011-0657-4S833840263Addicott FT (1982) Abscission. 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Lake sediments deposited on the Flims rockslide mass: the key to date the largest mass movement of the Alps
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