Soil health impacts of rubber farming: The implication of conversion of degraded natural forests into monoculture plantations

High revenues from rubber latex exports have led to a rapid expansion of commercial rubber cultivation and, as a consequence, the conversion of different land use types (e.g., natural forests) into rubber plantations, which may lead to a decrease in soil health. In this study in Quang Tri Province, Vietnam, we determined: (1) the variation of soil health parameters along a chronosequence of rubber tree stands and natural forests and (2) the relationships and potential feedback between vegetation types, vegetation structures and soil health. Our results revealed that: (1) soil health was higher in natural forests than in rubber plantations with a higher values in higher biomass forests; (2) soil health was lower in younger rubber plantations; (3) soil health depends on vegetation structure (with significantly positive relationships found between soil health and canopy cover, litter biomass, dry litter cover and ground vegetation cover). This study highlights the need for more rigorous land management practices and land use conversion policies in order to ensure the long-term conservation of soil health in rubber plantations

Changes in mangrove vegetation area and character in a war and land use change affected region of Vietnam (Mui Ca Mau) over six decades

Aerial photographs and satellite images have been used to determine land cover changes during the period 1953 to 2011 in the Mui Ca Mau, Vietnam, especially in relation to changes in the mangrove area. The mangrove area declined drastically from approximately 71,345 ha in 1953 to 33,083 ha in 1992, then rose to 46,712 ha in 2011. Loss due to herbicide attacks during the Vietnam War, overexploitation, and conversion into agriculture and aquaculture encouraged by land management policies are being partially counteracted by natural regeneration and replanting, especially a gradual increase in plantations as part of integrated mangrove-shrimp farming systems. The nature of the mangrove vegetation has markedly been transformed over this period. The results are valuable for management planning to understand and improve the contribution of mangrove forests to the provision of ecosystem services and resources, local livelihood and global interest

Effectiveness of cervical pessary compared to cervical cerclage with or without vaginal progesterone for the prevention of preterm birth in women with twin pregnancies and a short cervix : Study protocol for a two-by-two factorial randomised clinical trial

Peer reviewedPublisher PD

Seroepidemiology and Carriage of Diphtheria in Epidemic-Prone Area and Implications for Vaccination Policy, Vietnam

In 2019, a community-based, cross-sectional carriage survey and a seroprevalence survey of 1,216 persons 1–55 years of age were conducted in rural Vietnam to investigate the mechanism of diphtheria outbreaks. Seroprevalence was further compared with that of an urban area that had no cases reported for the past decade. Carriage prevalence was 1.4%. The highest prevalence, 4.5%, was observed for children 1–5 years of age. Twenty-seven asymptomatic Coerynebacterium diphtheriae carriers were identified; 9 carriers had tox gene–bearing strains, and 3 had nontoxigenic tox gene–bearing strains. Child malnutrition was associated with low levels of diphtheria toxoid IgG, which might have subsequently increased child carriage prevalence. Different immunity patterns in the 2 populations suggested that the low immunity among children caused by low vaccination coverage increased transmission, resulting in symptomatic infections at school-going age, when vaccine-induced immunity waned most. A school-entry booster dose and improved infant vaccination coverage are recommended to control transmissions

On The Determination Of The Magnetic Entropy Change In Materials With First-order Transitions

An accurate method to determine the magnetic entropy change in materials with hysteretic first-order transitions is presented, which is needed to estimate their potential for applications. We have investigated the effect of the maximal entropy change derived from magnetization measurements performed in different measurement processes. The results show that the isothermal entropy change can be derived from the Maxwell relations even for samples with large thermal hysteresis. In the temperature region with hysteresis, overestimating the entropy change can be avoided by measuring the isothermal magnetization of the sample after it is cooled from the paramagnetic state to the measurement temperature. In this way the so-called peak effect is not observed as shown here for a few compounds. © 2009 Elsevier B.V. All rights reserved.3212135593566Gschneidner, K.A., Pecharsky, V.K., Tsokol, A.O., (2005) Reports on Progress in Physics, 68, pp. 1479-1539Brück, E., (2005) Journal of Physics D-Applied Physics, 38, pp. R381-R391Pecharsky, V.K., Gschneidner, K.A., (1997) Physical Review Letters, 78, pp. 4494-4497Pecharsky, V.K., Gschneidner, K.A., (1997) Journal of Magnetism and Magnetic Materials, 167, pp. L179-L184Tegus, O., Brück, E., Buschow, K.H.J., de Boer, F.R., (2002) Nature, 415, pp. 150-152Wada, H., Tanabe, Y., (2001) Applied Physics Letters, 79, pp. 3302-3304Hu, F.X., Shen, B.G., Sun, J.R., Cheng, Z.H., Rao, G.H., Zhang, X.X., (2001) Applied Physics Letters, 78, pp. 3675-3677Terashita, H., Garbe, J.J., Neumeier, J.J., (2004) Physical Review B, 70, p. 094403Gama, S., Coelho, A.A., de Campos, A., Carvalho, A.M.G., Gandra, F.C.G., von Ranke, P.J., de Oliveira, N.A., (2004) Physical Review Letters, 93, p. 237202de Campos, A., Rocco, D.L., Carvalho, A.M.G., Caron, L., Coelho, A.A., Gama, S., Da Silva, L.M., de Oliveira, N.A., (2006) Nature Materials, 5, pp. 802-804Rocco, D.L., de Campos, A., Carvalho, A.M.G., Caron, L., Coelho, A.A., Gama, S., Gandra, F.C.G., de Oliveira, N.A., (2007) Applied Physics Letters, 90, p. 242507Xu, C., Li, G.D., Wang, L.G., (2006) Journal of Applied Physics, 99, p. 123913Giguere, A., Foldeaki, M., Gopal, B.R., Chahine, R., Bose, T.K., Frydman, A., Barclay, J.A., (1999) Physical Review Letters, 83, pp. 2262-2265Sun, J.R., Hu, F.X., Shen, B.G., (2000) Physical Review Letters, 85, p. 4191Liu, G.J., Sun, R., Shen, J., Gao, B., Zhang, H.W., Hu, F.X., Shen, B.G., (2007) Applied Physics Letter, 90, p. 032507de Oliveira, N.A., von Ranke, P.J., (2008) Physical Review B, 77, p. 214439Tegus, O., Brück, E., Zhang, L., Dagula, Buschow, K.H.J., de Boer, F.R., (2002) Physica B, 319, pp. 174-192Thanh, D.T.C., Brück, E., Tegus, O., Klaasse, J.C.P., Gortenmulder, T.J., Buschow, K.H.J., (2006) Journal of Applied Physics, 99, pp. 08Q107Hermann, R.P., Tegus, O., Brück, E., Buschow, K.H.J., de Boer, F.R., Long, G.J., Grandjean, F., (2004) Physical Review B, 70, p. 214425Liu, D., Yue, M., Zhang, J., McQueen, T.M., Lynn, J.W., Wang, X., Chen, Y., Huang, Q., (2009) Physical Review B, 79, p. 014435Wada, H., private communicatio