湖北湿地公园建设现状分析及发展思路探讨

本文在了解全省湿地现状的基础上,简要分析了湖北湿地公园建设发展现状,并对湖北湿地公园建设发展思路进行探索,提出了相应的观点.     

Cloning, expression, and characterization of the MSP1a and MSP1b recombinant proteins from PR1 Anaplasma marginale strain, Brazil

The Anaplasma marginale is a bacterium that has obligate intraerythrocytic multiplication in cattle causing important economic loss. The A. marginale major surface protein 1 (MSP1) complex, heterodimer composed of MSP1a and MSP1b, has been identified as adhesins for bovine erythrocytes. The objectives of this study were to sequences the msp1β gene and produce and characterize recombinant MSP1a and MSP1b from a Brazilian strain of A. marginale, PR1. The msp1α and msp1β genes from the PR1 strain were cloned and expressed in E. coli BL21 Star using the vectors pET102 and pET101/D-TOPO. Antibodies were produced against the recombinant proteins and were shown to react with rMSP1a and rMSP1b demonstrating a molecular mass of 70 kDa to 105 kDa and 100 kDa, respectively for these proteins. Bovine erythrocytes were agglutinated by BL21/rMSP1a and BL21/rMSP1b and, this agglutination was inhibited by the presence of the IgY anti-rMSP1a, confirming the adhesion function of these proteins. Additionally, using the IgY anti-rMSP1a and rMSP1b in a IFI, the presence of rMSP1a and rMSP1b was confirmed on the outer membrane of the recombinant E. coli BL21. Our results show that the msp1β gene from the PR1 strain has both the conserved region and contain the defined polymorphism regions previously described for other strains of A. marginale. The results from this study confirm adhesive functions for rMSP1a and rMSP1b from PR1 strain in bovine erythrocytes invasion.     

Rural economic development through local self-development strategies

During the 1980s many communities turned to grassroots activities to promote economic development, rather than relying on industrial recruitment strategies. We evaluate the characteristics of these projects, their benefits and costs, and obstacles they face in the development process. The data are drawn from a survey of more than one hundred communities in the United States. Self-development efforts do not appear to replace traditional rural economic development activities, but may complement them. Self-development activities produce a wide variety of jobs that are taken primarily by local residents. The cost and availability of credit are major obstacles for self-development projects. Although self-development strategies should not be considered the primary economic development strategy for most rural communities, they do enable communities to build a more viable local economy.     

Coffee ripeness monitoring using a UAV-mounted low-cost multispectral camera

Coffee beverage quality is highly correlated with the degree of fruit ripeness. In this sense, monitoring fruit ripeness is of utmost importance for harvest planning and, especially for obtaining high-quality beverages. Currently, this process is carried out through manual counts of unripe fruits, which is laborious and limited to a few plants within the field. This study aimed at evaluating the potential of a low-cost multispectral camera for coffee ripeness monitoring in the Zona da Mata region of Minas Gerais State, Brazil. For that, five fields of Arabica coffee with distinct characteristics were evaluated. During the coffee ripeness period, four flights were carried using a Phantom 4 Pro quadcopter equipped with a Mapir Survey 3W camera for imagery acquisition. After that, nine vegetation indices (VIs) were obtained. For the same dates, the percentage of unripe fruits was obtained using an irregular grid in all fields. The data was split into two ripeness classes: suitable for harvest (R) with?<?30% of unripe fruits; and not suitable for harvest (U), with?>?30% of unripe fruits. Then, a principal component analysis was used to infer the importance of the VIs to discriminate plants with unripe fruits from those with ripe fruits. The first two principal components explained?>?75% of the variance in the datasets from all coffee fields. The VIs were able to discriminate the ripeness classes (U and R) in most fields; however, their performance was directly influenced by the crop yield and canopy volume.

     

Assessment of genetic structure,habitat suitability and effectiveness of reserves for future conservation planning of the Euphrates soft‐shelled turtle Rafetus euphraticus (Daudin, 1802)

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Efficacy of two vaccine formulations against contagious bovine pleuropneumonia (CBPP) in Kenyan indigenous cattle

A live, attenuated vaccine is currently the only viable option to control of CBPP in Africa. It has been suggested that simple modifications to current vaccines and protocols might improve efficacy in the field. In this report we compared the current vaccine formulation with a buffered preparation that maintains Mycoplasma viability at ambient temperature for a longer time. Groups of animals were vaccinated with the two formulations and compared with non vaccinated groups. Half of the animals in each group were challenged 3 months post vaccination, the other half after 16 months. Protection levels were measured using the pathology index, calculated from post mortem scores of lesions from animals killed during the course of clinical disease. In the challenge at 3 months post vaccination, the protection levels were 52% and 77% for the modified and current vaccine preparations, respectively. At 16 months post vaccination, the protection levels were 56% and 62% for the modified and current vaccine preparations, respectively. These findings indicate that there are no differences in protection levels between the two vaccines. Because of its longer half life after reconstitution, the modified vaccine might be preferred in field situations where the reconstituted vaccine is likely not to be administered immediately.     

Heavy metal content and toxicity of mine and quarry soils

Purpose

Soils formed in metallic mines and serpentinite quarries, among other unfavourable features, have high levels of heavy metals. They can release into the environment causing surface and subsurface water contamination, uptake by plants, their accumulation in the food chain and adverse effects on living organisms. In this work, we studied the magnitude of the soils’ toxic effects not only on spontaneous plants but also on two species with phytoremediation potential.

Materials and methods

Several soils from two different exploitations were selected: a lead and zinc mine and a serpentinite quarry. Soils were characterized, and the pseudo-total and extractable contents of Co, Cr and Ni in soils from a serpentinite quarry were determined. The Cd, Pb and Zn pseudo-total and extractable contents were determined in soils developed in the Pb/Zn abandoned mine. Using a biotest, the chronic toxicity of the soil samples on higher plants was determined. Festuca ovina L., Cytisus scoparius (L.) Link., Sinapis alba L. and Brassica juncea L. were selected, the first two because they are spontaneous plants in the study areas and the last two because they have heavy metal phytoremediation potential.

Results and discussion

Pseudo-total contents of Co, Cr and Ni in the serpentinite quarry soils and of Zn, Pb and Cd in the Zn/Pb mine soils exceed generic reference levels. CaCl₂ is the reactant that extracts the highest proportion of Co, Cr and Ni in the quarry soils and EDTA the largest proportion of Pb Zn and Cd content in the mine soils. The germination index values based on seed germination and root elongation bioassays revealed increasing plant sensitivity to the mine soils in the following order: B. juncea?<?S. alba?<?F. ovina?<?C. scoparius. The wide range of GI values indicates that the response of test plants to soil heavy metals depended on their concentrations and soil characteristics, especially pH and organic matter content.

Conclusions

The pollution index indicates severe Cd, Pb and Zn contamination in the mine soils, as well as high Cr and Ni and moderate Co contamination in the serpentinite quarry soils. The performed biotests were suitable for identifying toxic soils and showed that the studied soils are toxic to the spontaneous plants, more to C. scoparius than to F. ovina. They also indicate that the mine soils are more toxic than the quarry soils for both species.

     

Silicon alleviates long-term copper toxicity and influences gene expression in Nicotiana tabacum

Silicon (Si) is beneficial for plant growth and aids in stress tolerance. In this study, the effects of Si on long-term copper (Cu) toxicity in the low Si accumulator Nicotiana tabacum were evaluated. Silicon supplementation alleviated growth inhibition in roots and shoots of N. tabacum exposed to Cu toxicity. Alleviation of Cu toxicity correlated with increased Si accumulation in roots and leaves, suggesting N. tabacum contains a stress-regulated mechanism for Si transport. Root Cu concentration decreased in Si-supplemented plants exposed to Cu toxicity. Interestingly, Copper Transporter 1 (COPT1) expression decreased in roots of Si-supplemented plants exposed to Cu toxicity, which may contribute to Cu uptake reduction. Decreases in ethylene (ET) biosynthetic gene expression were previously implicated in Si-mediated stress alleviation. In the present study, Si-mediated alleviation of Cu toxicity corresponded with increased ET biosynthetic gene expression.