29 research outputs found

    The impact of COVID-19 on labor migration and the roles of small-scale farming in the pandemic in Vietnam

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    Drawing on in-depth interviews of migrant workers and their families in rural Vietnam, this study explores the impact of the COVID-19 pandemic on transnational and rural-urban migration as well as the role of small-scale farming in remittance-receiving households. Fieldwork was conducted in two provinces: the Son La province where ethnic minority women and men work in urban construction sites, and the Ha Tinh province where young men work in East Asia, such as Japan, South Korea, and Taiwan. Research findings show that in Son La, the pandemic exacerbated the already precarious lives and livelihoods of labor migrants, especially women and children. On the other hand, in Ha Tinh non-market-oriented small-scale farming and livestock production support remittance-receiving households, thereby limiting the impact of reduced remittances from transnational migration in the short-term. In both study sites, the pandemic did not change respondentsā€™ perceptions of livelihood strategies. Labor migration remains the only available option for Son La farmers from the poor households to provide for their families and the best option for many young men in Ha Tinh to gain financial autonomy. These individuals are deeply affected by structural injustice in the commodification of the labor market, which is inherently unequal and exploitative. Current agricultural development must offer diverse options to accommodate the various needs of marginalized households that depend on off-farm incomes as well as small-scale farming

    Womenā€™s roles and opportunities in cassava value chains in Son La province in Vietnam: A technical report

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    Cassava is a major export-oriented cash crop in Vietnam. Unlike other cash crops, such as coffee, fruits, and maize, cassava requires limited agricultural input and labour and can grow in nutrient-poor uplands. Research on cassava breeding, seed systems and value chains in Southeast Asia is increasingly focused on market-oriented aspects such as developing hybrid varieties favourable to the cassava starch industry, disease control on large scale farms, and seed systems driven by the private sector. However, in the northern mountainous areas of Vietnam, ethnic minority farmers use cassava roots, leaves and sticks for numerous reasons, including starch production, fish and animal feed, firewood, and home consumption. Women play significant roles in those non market-oriented activities (often collecting left-over small roots in the field, drying roots, and cutting leaves and stems) but little is known about how this work influences womenā€™s roles, decision-making and opportunities in cassava value chains. Hence, this study provides that data with an eye to see how women may find more opportunity for creating small business enterprises with cassava. Fieldwork was conducted in July 2021 in the Chieng La commune (Thuan Chau district) and the Muong Bon Commune (Mai Son district). Findings show that although women are less involved in decision making on cassava production and overall agricultural investment, they play important roles in cassava production and post-harvest activities. Therefore, it is extremely important to collect and analyze womenā€™s preferences, concerns and constraints in cassava research and interventions. In the conclusion, we highlight additional areas for research on this topic

    Salmonella typhimurium Suppresses Tumor Growth via the Pro-Inflammatory Cytokine Interleukin-1 beta

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    Although strains of attenuated Salmonella typhimurium and wild-type Escherichia coli show similar tumor-targeting capacities, only S. typhimurium significantly suppresses tumor growth in mice. The aim of the present study was to examine bacteria-mediated immune responses by conducting comparative analyses of the cytokine profiles and immune cell populations within tumor tissues colonized by E. coli or attenuated Salmonellae. CT26 tumor-bearing mice were treated with two different bacterial strains: S. typhimurium defective in ppGpp synthesis (Delta ppGpp Salmonellae) or wild-type E. coli MG1655. Cytokine profiles and immune cell populations in tumor tissue colonized by these two bacterial strains were examined at two time points based on the pattern of tumor growth after Delta ppGpp Salmonellae treatment: 1) when tumor growth was suppressed ('suppression stage') and 2) when they began to re-grow ('re-growing stage'). The levels of IL-1 beta and TNF-alpha were markedly increased in tumors colonized by Delta ppGpp Salmonellae. This increase was associated with tumor regression; the levels of both IL-1 beta and TNF-alpha returned to normal level when the tumors started to re-grow. To identify the immune cells primarily responsible for Salmonellae-mediated tumor suppression, we examined the major cell types that produce IL-1 beta and TNF-alpha. We found that macrophages and dendritic cells were the main producers of TNF-alpha and IL-1 beta. Inhibiting IL-1 beta production in Salmonellae-treated mice restored tumor growth, whereas tumor growth was suppressed for longer by local administration of recombinant IL-1 beta or TNF-alpha in conjunction with Salmonella therapy. These findings suggested that IL-1 beta and TNF-alpha play important roles in Salmonella-mediated cancer therapy. A better understanding of host immune responses in Salmonella therapy may increase the success of a given drug, particularly when various strategies are combined with bacteriotherapy.111715Ysciescopu

    Properties of Neon, Magnesium, and Silicon Primary Cosmic Rays Results from the Alpha Magnetic Spectrometer

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    We report the observation of new properties of primary cosmic rays, neon (Ne), magnesium (Mg), and silicon (Si), measured in the rigidity range 2.15 GV to 3.0 TV with 1.8 x 10(6) Ne, 2.2 x 10(6) Mg, and 1.6 x 10(6) Si nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. The Ne and Mg spectra have identical rigidity dependence above 3.65 GV. The three spectra have identical rigidity dependence above 86.5 GV, deviate from a single power law above 200 GV, and harden in an identical way. Unexpectedly, above 86.5 GV the rigidity dependence of primary cosmic rays Ne, Mg, and Si spectra is different from the rigidity dependence of primary cosmic rays He, C, and O. This shows that the Ne, Mg, and Si and He, C, and O are two different classes of primary cosmic rays

    Towards Understanding the Origin of Cosmic-Ray Positrons

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    Precision measurements of cosmic ray positrons are presented up to 1 TeV based on 1.9 million positrons collected by the Alpha Magnetic Spectrometer on the International Space Station. The positron flux exhibits complex energy dependence. Its distinctive properties are (a) a significant excess starting from 25.2 +/- 1.8 GeV compared to the lower-energy, power-law trend, (b) a sharp dropoff above 284(-64)(+91) GeV, (c) in the entire energy range the positron flux is well described by the sum of a term associated with the positrons produced in the collision of cosmic rays, which dominates at low energies, and a new source term of positrons, which dominates at high energies, and (d) a finite energy cutoff of the source term of E-s = 810(-180)(+310) GeV is established with a significance of more than 4 sigma. These experimental data on cosmic ray positrons show that, at high energies, they predominantly originate either from dark matter annihilation or from other astrophysical sources

    Properties of Cosmic Helium Isotopes Measured by the Alpha Magnetic Spectrometer

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    Precision measurements by the Alpha Magnetic Spectrometer (AMS) on the International Space Station of He-3 and He-4 fluxes are presented. The measurements are based on 100 million He-4 nuclei in the rigidity range from 2.1 to 21 GV and 18 million He-3 from 1.9 to 15 GV collected from May 2011 to November 2017. We observed that the He-3 and He-4 fluxes exhibit nearly identical variations with time. The relative magnitude of the variations decreases with increasing rigidity. The rigidity dependence of the He-3/He-4 flux ratio is measured for the first time. Below 4 GV, the He-3/He-4 flux ratio was found to have a significant long-term time dependence. Above 4 GV, the He-3/He-4 flux ratio was found to be time independent, and its rigidity dependence is well described by a single power law proportional to R-Delta with Delta = 0.294 0.004. Unexpectedly, this value is in agreement with the B/O and B/C spectral indices at high energies

    Towards Understanding the Origin of Cosmic-Ray Electrons

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    Precision results on cosmic-ray electrons are presented in the energy range from 0.5 GeV to 1.4 TeV based on 28.1 x 10(6) electrons collected by the Alpha Magnetic Spectrometer on the International Space Station. In the entire energy range the electron and positron spectra have distinctly different magnitudes and energy dependences. The electron flux exhibits a significant excess starting from 42.1(-5.2)(+5.4) GeV compared to the lower energy trends, but the nature of this excess is different from the positron flux excess above 25.2 +/- 1.8 GeV. Contrary to the positron flux, which has an exponential energy cutoff of 810(-180)(+310) GeV, at the 5 sigma level the electron flux does not have an energy cutoff below 1.9 TeV. In the entire energy range the electron flux is well described by the sum of two power law components. The different behavior of the cosmic-ray electrons and positrons measured by the Alpha Magnetic Spectrometer is clear evidence that most high energy electrons originate from different sources than high energy positrons

    Precision Measurement of Cosmic-Ray Nitrogen and its Primary and Secondary Components with the Alpha Magnetic Spectrometer on the International Space Station

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    A precision measurement of the nitrogen flux with rigidity (momentum per unit charge) from 2.2 GV to 3.3 TV based on 2.2 x 10(6) events is presented. The detailed rigidity dependence of the nitrogen flux spectral index is presented for the first time. The spectral index rapidly hardens at high rigidities and becomes identical to the spectral indices of primary He, C, and O cosmic rays above similar to 700 GV. We observed that the nitrogen flux Phi(N) can be presented as the sum of its primary component Phi(P)(N) and secondary component Phi(S)(N), Phi(N) = Phi(P)(N) + Phi(S)(N), and we found Phi(N) is well described by the weighted sum of the oxygen flux Phi(O) (primary cosmic rays) and the boron flux Phi(B) (secondary cosmic rays), with Phi(P)(N) = (0.090 +/- 0.002) x Phi(O) and Phi(S)(N) = (0.62 +/- 0.02) x Phi(B) over the entire rigidity range. This corresponds to a change of the contribution of the secondary cosmic ray component in the nitrogen flux from 70% at a few GV to < 30% above 1 TV
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