Modelling and Optimization of Clean and Affordable Electricity Solution for Small-Scale Savings and Credit Cooperatives(SACCOs)

Renewable energy exploitation is among the development strategies set by the government of Rwanda on the roadmap to 2023/2024 universal electricity access and theUnitedNations plans by 2030.Numerous previous studies oncleanenergy technologies inRwandahavemostly focusedonhouseholds’usagebut there are currentlynostudies describing the feasibility of clean energy technologies for financial institutions.The skepticism on renewable energy in Africa was previously reported by some personnel.Having realized that most SACCOs(Savings and Credit Co-Operatives)in Rwanda use diesel technology for backup/emergency electricity supply,taking consideration of abundant solar resources in Rwanda,having seen the viability and feasibility studies from other countries of renewable energy for different institutions(financial included);thiswork uses theHOMEREnergy Software and the electricity load profile of a typical SACCO in Rwanda to analyse the affordability and viability of on-site renewable energy generation for SACCO in Rwanda.The results reveal that a solar PV systemwith storage can be the optimal solution(with levelized cost of electricity(LCOE)of 0.713$/kWh which is cheaper than 0.73$/kWh for diesel technology)for SACCOs located in both off-grid areas and grid-connected areas(with 0.041$/kWh LCOE which is lower than the current electricity tariff in Rwanda).The findings in this work can serve as basic tools/materials for policy drafters in Rwanda on how financial institutions can contribute to climate change mitigation through self-renewable energy exploitation.

A research on the effect of plasma spectrum collection device on LIBS spectral intensity

Only a small amount of spectral information is collected because the collection solid angle of the optical fiber probe and lens is very limited when collecting spectral information.To overcome this limitation,this study presents a novel method for acquiring plasma spectral information from various spatial directions.A parabolic-shaped plasma spectral collection device(PSCD)is employed to effectively collect more spectral information into the spectrometer,thereby enhancing the overall spectral intensity.The research objects in this study were soil samples containing different concentrations of heavy metals Pb,Cr,and Cd.The results indicate that the PSCD significantly enhances the spectral signal,with an enhancement rate of up to 45%.Moreover,the signal-to-noise ratio also increases by as much as 36%.Simultaneously,when compared to the absence of a device,it is found that there is no significant variation in plasma temperature when the PSCD is utilized.This observation eliminates the impact of the spatial effect caused by the PSCD on the spectral intensity.Consequently,a concentrationspectral intensity relationship curve is established under the PSCD.The results revealed that the linear fitting R^(2)for Pb,Cr,and Cd increased by 0.011,0.001,and 0.054,respectively.Additionally,the limit of detection(LOD)decreased by 0.361 ppm,0.901 ppm,and 0.602 ppm,respectively.These findings indicate that the spectral enhancement rate elevates with the increase in heavy metal concentration.Hence,the PSCD can effectively enhance the spectral intensity and reduce the detection limit of heavy metals in soil.

Automatic segmentation of brain tissue based on improvedfuzzy c means clustering algorithm

In medical images, exist often a lot of noise, the noise will seriously affect the accuracy of the segmentation results. The traditional standard fuzzy c-means(FCM) algorithm in image segmentation do not taken into account the relationship the adjacent pixels, which leads to the standard fuzzy c-means(FCM) algorithm is very sensitive to noise in the image. Proposed improvedfuzzy c-means(FCM) algorithm, taking both the local and non-local information into the standard fuzzy c-means(FCM) clustering algorithm. The ex-periment results can show that the improved algorithm can achieve better effect than other methods of brain tissue segmentation.

Cross-species binding spectrum of ACE2 to SARS-CoV-2 RBD

Dear Editor,Severe acute respiratory syndrome coronavirus 2(SARSCo V-2)is the cause of COVID-19,which has posed a massive threat to human health,economy,and security worldwide(Bai et al.,2022).Genomic analysis of SARS-Co V-2 and related coronaviruses revealed that SARS-Co V and SARS-Co V-2likely had ancestors(Xu et al.,2020),which might originate in bats,followed by subsequent spread within intermediate hosts(spillover hosts)and then transmission to humans(Wang et al.,2021).

CO_(2)-elevated cell-free protein synthesis

Gases are the vital nutrition of all organisms as the precursor of metabolism pathways.As a potential biological process,protein synthesis is inevitably regulated by gas transport and utilization.However,the effect of carbon dioxide(CO_(2))present in many metabolic pathways on protein synthesis has not been studied well.In this work,carbon dioxide combined with oxygen was employed for cell-free protein synthesis(CFPS)in the tube-in-tube reactor with precise control of gas concentration.In this in vitro system,gases could directly affect the protein synthesis process without transmembrane transport.Varied concentrations of carbon dioxide(0-1%)and constant oxygen concentration(21%)were employed for CFPS to assess the effects.The cell-free reactions with 0.3%CO_(2) and 21%O_(2) showed the highest protein yields.The combined effect of CO_(2) and O_(2) also resulted in relatively high protein expression under high oxygen conditions(0.3%CO_(2) and 100%O_(2)).Moreover,metabolomics assays were performed to gain insight into metabolic changes,which showed that CO_(2) slightly improved energy metabolism and redox balance.In particular,the extra supplied CO_(2) activated the decarboxylating reactions and removed toxic metabolites to recover the protein synthesis activity.The exploration of CO_(2) on protein synthesis could provide guiding implications for basic studies and biomanufacturing.