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131.
Kratom (Mitragyna speciosa) belongs to the coffee family of Rubiaceae. The tree is native to Southeast Asia and primarily grown in Malaysia, Thailand, and Indonesia. Recently, it has been introduced and cultivated in other countries including the United States. The leaves and extracts of the leaves are used for medicinal and recreational purposes. In February 2022, kratom root and soil samples were submitted to the University of Florida Nematode Assay Laboratory for diagnosis by a commercial grower in Florida. Root galls were observed on the roots. On examination of soil and root samples, it is revealed that high numbers of root-knot nematodes (Meloidogyne sp.) are present. Molecular species identification was performed by a combination of the mitochondria haplotyping and species-specific primer techniques using TRNAH/MHR106 and MORF/MTHIS primer sets and Meloidogyne incognita-specific primers (MIF/MIR). The root-knot nematode infecting kratom is identified as M. incognita by molecular analysis. To our knowledge, this paper is the first report of M. incognita infecting kratom in the United States.  相似文献   
132.
Protection of forests because of their association with religious traditions is a worldwide phenomenon. These sacred forests play a key role in maintaining ecosystem services in regions affected by land system change. In the northern highlands of Ethiopia, the Ethiopian Orthodox Tewahido Church controls the majority of the surviving native forest. However, the reasons why communities value the forests and the ways they use and manage them are not well understood. We use data and analysis from an interdisciplinary project and ethnographic research, in particular, to explain how Ethiopian church forests function. Church forests represent an unusual form of community-based protection that integrates locally controlled common property with external institutional arrangements: this hybrid system is highly effective at protecting the forest while maintaining cultural practices. Our results inform theoretical debates about models of tropical forest protection and question assumptions about church forests being the product of a nature conservation imperative.  相似文献   
133.
A study was undertaken with the objective to identify some intrinsic (genotype of the cow, estrus time and parity) and extrinsic factors (service type, service time and estrus seasons) that affect calf sex ratio in naturally and artificially bred cattle in the central highlands of Ethiopia. A total of 4657 calving events were extracted from the long-term dairy cattle genetic improvement experiment at Holetta Agricultural Research Center. Factors that affect the logit of the probability of a female calf being born were obtained by using PROC GENMODE in Statistical Analysis System. Moreover, multivariate analysis was performed using PROC LOGISTIC procedure using forward selection procedure. Accordingly, genotype of the cow, parity, estrus season, and service type had considerable influences on calf sex ratio. However, estrus time and service time did not affect calf sex ratio (χ2 = 0.83 and 0.79, respectively). In Ethiopia, smallholder dairy farmers often complain that artificial insemination (AI) skewed to producing more male calves. However, our study showed that AI did not alter female-to-male calf sex ratio. On the contrary, natural mating increases the probability of female calves born (odds ratio 1.38) over AI. Heifer/cows that showed estrus and bred during the harsh seasons of the years produced more female calves than those that bred during the good seasons of the year. This strongly agreed with Trivers and Willard sex allocation theory.  相似文献   
134.
Dynamic clusters of lipid-anchored Ras proteins are important for high-fidelity signal transduction in cells. The average size of Ras nanoclusters was reported to be independent of protein expression levels, and cholesterol depletion is commonly used to test the raft-preference of nanoclusters. However, whether protein concentration and membrane domain stability affect Ras clustering in a reversible manner is not well understood. We used coarse-grained molecular dynamics simulations to examine the reversibility of the effects of peptide and cholesterol concentrations as well as a lipid domain-perturbing nanoparticle (C60) on the dynamics and stability of H-Ras lipid-anchor nanoclusters. By comparing results from these simulations with previous observations from the literature, we show that effects of peptide/cholesterol concentrations on the dynamics and stability of H-Ras peptide nanoclusters are reversible. Our results also suggest a correlation between the stabilities of lipid domains and Ras nanoclusters, which is supported by our finding that C60 penetrates into the liquid-disordered domain of the bilayer, destabilizing lipid domains and thereby the stability of the nanoclusters.  相似文献   
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