The dynamic range and low stoichiometry of protein phosphorylation frequently demands the enrichment of phosphorylated peptides from protein digests prior to mass spectrometry. Several techniques have been reported in literature for phosphopeptide enrichment, including metal oxides such as TiO(2) and ion metal affinity chromatography (IMAC). While the metal oxides have been used with reasonable success, IMAC has suffered from reduced selectivity and poor reproducibility. In this report, we present the first demonstration of the use of immobilized zirconium on a phosphonate-terminated self-assembled monolayer (SAM) for specific phosphopeptide capture and direct analysis by MALDI MS. By using the herein described functionalized-surface-based technology, efficient enrichment of phosphopeptides in different standard test systems such as alpha- or beta-casein digests or synthetic phosphopeptides spiked in nonphosphorylated protein digest has been demonstrated. The limit of detection for a beta-casein phosphopeptide was assessed to be at the low femtomole level. Compared to other state-of the-art technologies, like use of TiO(2) and Fe-IMAC, the presented technique demonstrated a superior performance with respect to specificity and bias with respect to singly or multiply phosphorylated peptides. Additionally, this platform was also successfully applied for ESI sample preparation, providing detailed sequence information of the investigated phosphopeptide. This technology was also proven to be applicable for real life samples such as phosphorylation site analysis of recombinant human MAPK1 and HSP B1 isolated from a 2D-gel spot by phosphopeptide enrichment and direct MALDI MS/MS.

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Climate change continues to pose a constant threat to nature and human beings, and thus demands adaptability and flexibility in forestry and domestic land use management. In this context, the Reducing Emission from Deforestation and Forest Degradation (REDD+) project was introduced to harness forests to curb greenhouse gas emissions in an effort to combat climate change. As of 2020, REDD+ was implemented in 65 countries across the world, including Vietnam. While the missions of afforestation and forest protection cannot be accomplished without the aid of local residents, low participation from stakeholders, particularly poor farmers, is an obstacle in climate mitigation projects. To contribute to improving REDD+ with a useful Vietnam reference, this study uses a random sample approach coupled with a face-to-face interview method to survey 215 households in Chau Thai, one of 206 poor communes in Nghe An province, to learn about (1) residents’ perception towards the importance of forests, (2) how forests contribute as a source of livelihood, (3) potential for household engagement in REDD+. The research findings show that the important role of forests is well acknowledged, the majority of forestland was allocated to plantation forests, and the seeds are carefully selected to satisfy market demand. In addition, forests are recorded to make major contributions to residents’ income and roughly four-fifths of households revealed their willingness to get involved in the REDD+ project with a monthly subsidy of 500–2000 kVND (22.3–89.2 USD). The study provides valuable information about forest-based rural livelihood and policy options to facilitate REDD+ participation among farmers. This, in turn, helps devise more appropriate policies for climate change mitigation and sustainable rural mountainous development nationwide and beyond.

The paper aims to examine the factors affecting brand and student decision in buying fresh milk. Combining qualitative and quantitative research methods, this study used self-completed questionnaires to investigate 520 students in Ho Chi Minh City. The results of the study show that that there are five key determinants affecting the dairy brand and student decision in buying fresh milk, including: (1) product quality, (2) fair price, (3) product promotion and customer services, (4) product convenience, and (5) reference group's attitude to the brand. In addition, it is also found that product brand has a direct and positive impact on the student decision. The finding in this study is quite different from other existing literatures in terms of the importance level of the determinants of the student decision in buying fresh milk; specifically, in deciding to buy their fresh milk, students are often interested in the promotion and customer service, the product convenience, and the reference group for the purchase, more than in the quality and price of the product. From these findings, some managerial implications are proposed for policy-makers and relevant enterprises to have appropriate policies and strategies for their business development.