Value Chain Analysis of Bamboo Production: The Case of Bule Woreda, Gedeo Zone, Snnprs

Bamboo plays very important role socially, economically and ecologically. Despite the fact that bamboo play important role in improving the livelihood of the local community it has an insignificant contribution due to the products are at a very rudimentary level and inexistence of well established bamboo industry. These situations hampered the opportunity of the potential of bamboo that will improve the poor living standards and hence sustainable utilization of the resources. This study was initiated to analyze the existing bamboo market chain in Bule Woreda Gedeo Zone, Southern Nations Nationalities and Regional State. The focus of the study was to  analyze the determinants of marketable supply of Bamboo, identify actors involved in the processes and what do they actually do, investigate the costs incurred by each participants and the benefits driven by each. The data were collected by using a semi-structured questionnaires together with secondary data gathered from agricultural bureau offices and other unpublished sources. Robust Ordinary least square regression econometric model was used to analyze the determinants of market supply of bamboo. The results from this analysis indicates that price of bamboo culm, educational level of producers, distance to the nearest market, and access to market information were found to be  significant variables influencing bamboo supply to the market. A significant amount (70.16%) of bamboo produced is channeled through producers- traders- processors- consumers chain. The concentration ratio of two firms measures of market structure indicated there exist  super tight oligopolistic nature of bamboo market. Moreover, marketing margins also indicate that the producers get much lower benefit than any other market chain actors. The major problems of the production identified by bamboo producers in the study area arised from road infrastructure and market information. Therefore improving road infrastructure, provision of formal education and market information,  and improving the existing chain through creating appropriate market linkage are recommended. Keywords: Value chain, value chain analysis, structure- conduct- performance, concentration ratio, marketing channel and marketing margin

Recursive Selective Harmonic Elimination for Multilevel Inverters: Mathematical Formulation and Experimental Validation

A recursive method that eliminates +1 harmonics and their respective multiples from the output voltage of a cascaded H-bridge multilevel inverters with = 2 dc sources ( = 1, 2, 3,...) is proposed. It solves 2×2 linear systems with not singular matrices and always gives an exact solution with very low computational effort. Simulated results in three-phase five, nine, seventeen and thirty three level CHB inverters, and experimental results in five-level inverter demonstrate the validity of the method

Knockdown of nicotinamide N-methyltransferase suppresses proliferation, migration and chemoresistance of Merkel cell carcinoma cells in vitro

Merkel cell carcinoma (MCC) is an aggressive skin cancer, with a propensity for early metastasis. Therefore, early diagnosis and the identification of novel targets become fundamental. The enzyme nicotinamide N-methyltransferase (NNMT) catalyzes the reaction of N-methylation of nicotinamide and other analogous compounds. Although NNMT overexpression was reported in many malignancies, the significance of its dysregulation in cancer cell phenotype was partly clarified. Several works demonstrated that NNMT promotes cancer cell proliferation, migration, and chemoresistance. In this study, we investigated the possible involvement of this enzyme in MCC. Preliminary immunohistochemical analyses were performed to evaluate NNMT expression in MCC tissue specimens. To explore the enzyme function in tumor cell metabolism, MCC cell lines have been transfected with plasmids encoding for short hairpin RNAs (shRNAs) targeting NNMT mRNA. Preliminary immunohistochemical analyses showed elevated NNMT expression in MCC tissue specimens. The effect of enzyme downregulation on cell proliferation, migration, and chemosensitivity was then evaluated through MTT, trypan blue, and wound healing assays. Data obtained clearly demonstrated that NNMT knockdown is associated with a decrease of cell proliferation, viability, and migration, as well as with enhanced sensitivity to treatment with chemotherapeutic drugs. Taken together, these results suggest that NNMT could represent an interesting MCC biomarker and a promising target for targeted anti-cancer therapy

NNMT (nicotinamide N-methyltransferase)

Review on NNMT (nicotinamide N-methyltransferase), with data on DNA, on the protein encoded, and where the gene is implicated

Expression and co-expression analyses of TMPRSS2, a key element in COVID-19

The ACE2 receptor is, so far, the best-known host factor for SARS-CoV-2 entry, but another essential element, the TMPRSS2 protease, has recently been identified. Here, we have analysed TMPRSS2 expression data in the lung correlating them with age, sex, diabetes, smoking habits, exposure to pollutant and other stimuli, in order to highlight which factors might alter TMPRSS2 expression, and thus impact the susceptibility to infection and COVID-19 prognosis. Moreover, we reported TMPRSS2 polymorphisms affecting its expression and suggested the ethnic groups more prone to COVID-19. Finally, we also highlighted a gender-specific co-expression between TMPRSS2 and other genes related to SARS-CoV-2 entry, maybe explaining the higher observed susceptibility of infection in men. Our results could be useful in designing potential prevention and treatment strategies regarding the COVID-19

Promising extracellular vesicle-based vaccines against viruses, including SARS-CoV-2

Extracellular vesicles (EVs) are secreted from almost all human cells and mediate intercellular communication by transferring heterogeneous molecules (i.e., DNA, RNAs, proteins, and lipids). In this way, EVs participate in various biological processes, including immune responses. Viruses can hijack EV biogenesis systems for their dissemination, while EVs from infected cells can transfer viral proteins to uninfected cells and to immune cells in order to mask the infection or to trigger a response. Several studies have highlighted the role of native or engineered EVs in the induction of B cell and CD8(+) T cell reactions against viral proteins, strongly suggesting these antigen-presenting EVs as a novel strategy for vaccine design, including the emerging COVID-19. EV-based vaccines overcome some limitations of conventional vaccines and introduce novel unique characteristics useful in vaccine design, including higher bio-safety and efficiency as antigen-presenting systems and as adjuvants. Here, we review the state-of-the-art for antiviral EV-based vaccines, including the ongoing projects of some biotech companies in the development of EV-based vaccines for SARS-CoV-2. Finally, we discuss the limits for further development of this promising class of therapeutic agents

Nonlinear optimal control for multilevel inverters

The article proposes a nonlinear optimal (H-infinity) control approach for the model of modular multilevel inverters. The article's results are of interest for power grid applications were to handle high voltage one can use low voltage semiconductors. To solve this control problem, the dynamic model of the inverter undergoes first approximate linearization around a time-varying operating point. The linearization procedure relies on Taylor series expansion and on the computation of the related Jacobian matrices. To compute the feedback gains of the H-infinity controller, an algebraic Riccati equation has to be solved at each time-step of the control method. To prove the global asymptotic stability of the control loop as well as robustness properties, Lyapunov stability analysis is performed