The antimicrobial activity of the total alkaloids from five medicinal plants namely Jatropha curcas, Calotropis procera, Magifera indica, Carica papaya and Psidium guajava, commonly used in northern Nigeria for the treatment of various ailments was evaluated using disc diffusion assay. The extracts were used against three bacterial isolates and two fungal isolates including Staphylococcus aureus, Streptococci, Lactobacillus spp., Actinomycetes and Candida albicans, respectively. The results obtained show that all the plants contains various level of alkaloids and an appreciable level of antimicrobial activities were observed at a concentration level of 6x10 2 µg/cm 3 indicating that the plants could be a potential source of alkaloids that may be used for the treatment of various microbial diseases caused by the tested organisms.

The hole transporting material (HTM) is responsible for selectively transporting holes and blocking electrons which also plays a crucial role in the efficiency and stability of perovskite solar cells (PSCs). Spiro-MeOTAD is the most popular material, which is expensive and can be easily affected by moisture content. There is a need to find an alternative HTM with sufficiently high resistance to moisture content. In this paper, the influence of some parameters with cuprous oxide (Cu2O) as HTM was investigated using a solar cell capacitance simulator (SCAPS). These include the influence of doping concentration and thickness of the absorber layer, the effect of thickness of ETM and HTM as well as electron affinities of ETM and HTM on the performance of the PSCs. From the obtained results, it was found that the concentration of dopant in the absorber layer, the thickness of ETM and HTM and the electron affinity of HTM and ETM affect the performance of the solar cell. The cell performance improves greatly with the reduction of ETM electron affinity and its thickness. Upon optimization of parameters, power conversion efficiency for this device was found to be 20.42% with a current density of 22.26 mAcm-2, voltage of 1.12 V, and fill factor of 82.20%. The optimized device demonstrates an enhancement of 58.80%, 2.25%, 20.40% and 30.23% in PCE, Jsc, FF, and Voc over the initial cell. The results show that Cu2O in lead-based PSC as HTM is an efficient system and an alternative to spiro-MeOTAD.

To authenticate the claims by local users of Citrus x limon (lemon) in the control of some human infections, preliminary phytochemical screening and antimicrobial evaluation of lemon leaf extract was investigated Extraction of plant leaves was performed using successive reflux, with n-hexane, ethyl acetate, ethanol and water as extracting solvents. Ethanol gave the highest percentage yield of 10.93% followed closely by ethyl acetate with 9.42% while water extract gave the lowest yield of 3.67%. 11 phytochemicals classes were present in the leaf extract and they include alkaloids, flavonoids, saponins, anthraquinon, cardiac glycosides, tannins, steroids, terpenes, resins, phenols

Metal nanoparticles have demonstrated outstanding properties in photovoltaic devices through introducing localized surface plasmon effects. The performance of Perovskite solar cell (PSC) by incorporating Ag@P4VP NPs was investigated systematically. The plasmonic enhancement effects are explored based on the combination of UV-visible absorption spectroscopy and Scanning Electron Microscope (SEM). The performance, especially the short circuit current density (Jsc), and open circuit voltage (Voc) of the PSC containing Ag@P4VP NPs was significantly affected. The power conversion efficiency (PCE), Jsc and Vocof the reference device shows a value of 3.80 %, 11.04 mAcm−2 and 0.85 V. Upon introducing AgNPs@P4VP, a PCE of 5.69 %, Jsc of 12.61 mAcm−2 and Voc of 0.88 V were recorded, which improved the PCE ∼ 39.4 % over that of the standard device. The improvement is attributed to an increase in photocurrent density due to enhanced light harvesting by silver nanoparticles.

The antibacterial properties of K. senegalensis stem bark extract can be harnessed for the production of new antibiotics or the enhancement of already existing antibiotics.

This study is a follow up to our previously published manuscript on "improved power conversion efficiency in Perovskite solar cell using silver nanoparticles modified photoanode". Three more photoanodes were fabricated which are: Ag@ P 4 VP NPs mixed with perovskite layer (S2), Ag@P 4 VP NPs simultaneously mixed both in TiO 2 and perovskite films (S3) and P25 NP simultaneously mixed both in TiO 2 and perovskite absorber (S4) and their performances were investigated systematically. The performance, especially the photocurrent, and open circuit voltage of PSCs made of Ag@P 4 VP NPs were significantly affected. The champion device is S3, which shows enhancement in power conversion efficiency (PCE) from 3.80 to 9.05%, short circuit current density (Jsc) from 11.04 to 15.87 mA cm −2 , open circuit voltage (Voc) from 0.85 to 0.88 and fill factor (FF) from 0.41 to 0.65, which demonstrates ~ 2.38 times improvement in PCE over the control device (C). When Ag@P 4 VP NPs was mixed with TiO 2 , PCE of 5.69%, Jsc of 12.61 mA cm −2 , Voc of 0.88 V and FF of 0.51 were achieved, which shows ~ 1.50 times improvement over the performance of the reference cell. Also, when Ag@P 4 VP NPs was mixed with the perovskite layer, PCE of 8.08%, Jsc of 14.18 mA cm −2 , Voc of 0.89 V and FF of 0.64 were achieved, which shows ~ 2.13 times improvement over the performance of the pristine device. The addition of Ag@P 4 VP NPs enhanced exciton generation and dissociation, encouraging charge separation/transfer, as well as reducing quenching losses. For the hysteresis test, it was found that the devices with Ag@P 4 VP NPs have almost identical J-V curves with negligible hysteresis, which is attributed to the significant reduction of the trap density of the perovskite film when Ag@P 4 VP NPs is incorporated to fill the pores with high trapping rate. We however observed hysteretic behavior in devices C and S4, which makes it difficult to estimate the real PCE.

Background: Blood transfusion saves life but it is also a major risk factor in the transmission of certain infections such as malaria, which remains a public health problem in tropical and sub-Saharan Africa. Methodology: This study investigated the prevalence of malaria among 550 blood donors aged 18 to 60 years from blood bank units of some selected hospitals in Federal Capital Territory (FCT), Abuja, using gold standard microscopy for malaria parasite detection. Results: Two hundred and fifty two (45.8%) donors were positive for malaria parasites. Replacement donors had higher prevalence rate of malaria compared to voluntary donors. The distribution of infection on the basis of age revealed the highest prevalence rate of malaria among the 20-29yrs age group. The rate of infection among the males and the females was not significantly different (p>0.05). No association was observed between the blood group types and the rate of malaria infection (p > 0.05). Conclusion: A high prevalence of malaria parasitaemia was observed among blood donors in FCT, Abuja, Nigeria in this study. The introduction of malaria screening as part of routine screening for blood donation and the provision of modern blood screening equipment within healthcare facilities are highly advocated.

Antibiotics resistance profiles of bacteria from surgical wounds were investigated in four (4) General Hospitals (Bida, Kontagora, Minna and Suleja) in Niger State. Five hundred (500) samples (i.e. Two hundred (200) samples in Minna, One hundred (100) samples each Suleja, Kontagora and Bida) of wound exudates from these general hospitals, were analysed. The results showed the presence of Klebsiella Pneumoniae, Escherichia coli, Pseudomonas aeruginosa, and Proteus vulgaris in the samples from the wounds. From the five hundred (500) samples collected from all locations, forty two (42) samples had Kl. pneumoniae, sixty four (64) samples had Ps. aeruginosa, fifty two (52) samples had P. vulgaris and one hundred and nine (109) samples had E. coli. E. coli was the most frequently isolated bacteria from wounds in all the locations, while Kl. pneumoniae was the least isolated from wounds in all the locations. All the bacteria were tested for sensitivity against tarivid, pefloxacin, ciprofloxacin, augmentin, gentamycin, streptomycin, ceporex, nalidixic acid, septrin, ampicillin, ampiclox, zinacef, amoxacillin, rocephin, erythromycin. Most of all the isolates were sensitive to ciprofloxacin, pefloxacin and Tarivid while others were resistant to remaining antibiotics. E. coli, Strept. pyogenes and S. aureus showed highest resistance profile and P. vulgaris, Kl. pneumoniae and Ps. aeruginosa showed least resistance profile to most antibiotics used.