High Concentration Phenol Removal Using Freshwater Microalgae

The ability of three freshwater microalgae strains, namely Chlorella sp., Pseudochlorococcum sp. and Chlamydomonas sp. to grow in water containing different concentrations of phenol has been tested. The effectiveness of the selected strains to utilize the phenol as a carbon source and reduce its concentration has also been assessed. The phenol removal efficiency and cells growth rates were evaluated at different initial phenol concentrations, in the range of 100-450 ppm. It was found that growing, under a reduced illumination condition, increased the inhibition onset concentration, enhanced the phenol removal and allowed the strains to tolerate higher phenol concentrations reaching 450 ppm. In the tested range of the phenol concentrations, Chlamydomonas sp. has shown to have the highest specific growth rate of 0.59 day-1, whereas Pseudochlorococcum sp showed the highest phenol removal rate of 166 ppm day-1. Three kinetics models that incorporate substrate inhibition were tested to describe the growth, which show almost identical fittings

Jajar Legowo Planting System with SRI Method (System of Rice Intensification) and the Use of Planting Tools for Caplak in Simatohir Village, Padangsidimpuan District Angkola Julu

This community service took place in Simatohir Village, Padangsidimpuan District Angkola Julu, Padangsidimpuan City. The implementation methods used are counseling methods, cultivation technique training, and mentoring. The approach method used is: a) Counseling about the application of SRI technology. b) Make demonstration plots or demonstration plots. c) Use of 2 : 1 legowo planting system using ticks. In the generative phase clearly visible results from the application of SRI are applied to the rice field cropping. There is a distance that facilitates the care of farmers, efficiency in the use of paddy water and the number of productive tillers is 25-40 tillers / clumps and the yield reaches 1337 tons with an area of ​​1000 square meters and this difference is very obvious when farmers do not use SRI , which starts from tillage which is only extracted, unbalanced fertilization, irregular irrigation, perforated plants between 10-20 plants with productive tillers only 15-23 tillers. This will have an impact on harvest yields which only reach 900 kg with an area of​​ 1000 square meters

PEMBUATAN PUPUK ORGANIK CAIR (POC) ASAM AMINO SEBAGAI PENGGANTI PUPUK NPK DARI AIR KELAPA DI DESA SIMATOHIR

Pupuk adalah bahan yang memiliki kandungan satu atau lebih unsur hara yang diberikan pada tanaman untuk mendukung pertumbuhan tanaman. Pupuk terbagi atas 2 (dua) macam yaitu pupuk anorganik (kimia) dan pupuk organik (pembusukan bahan organik) bisa berasal dari sisa tanaman, kotoran hewan dan kotoran yang umumnya dari proses penguraian (fermentasi). Adapun hasil fermentasi yang dapat dimanfaatkan sebagai POC pada kegiatan pengabdian di desa Simatohir  ini adalah fermentasi dari bakteri yakult dengan menambahkan air kelapa dan sumber protein dari telur. Kegiatan ini bertujuan untuk meningkatkan kesuburan tanah sekaligus produksi tanaman dari pembuatan Pupuk Organik Cair (POC) asam amino menggantikan pupuk NPK (kimia). .Hasil kegiatan di publikasikan dalam bentuk jurnal di jurnal MARTABE

Polyaniline-modified nanocellulose prepared from Semantan bamboo by chemical polymerization: preparation and characterization

Crystalline nanocellulose was prepared from Semantan bamboo (Gigantochloa scortechinii) via acid hydrolysis and was used to synthesize a nanocomposite of polyaniline/crystalline nanocellulose (PANi/CNC) via in situ oxidative polymerization of aniline in the presence of crystalline nanocellulose. The electrochemical properties of the nanocomposite were studied using a modified PANi/CNC electrode via cyclic voltammetry, and higher current response was observed for the PANi/CNC-modified electrode compared to that for the modified electrode with PANi. The results obtained from EIS displayed lower value of Rct for the PANi/CNC-modified electrode, indicating that the incorporation of CNC into the PANi structure could enhance the electron transfer rate. The characteristic peaks of PANi and CNC were observed in the FTIR spectra of the nanocomposite, indicating the incorporation of CNC inside the nanocomposite structure. Moreover, in the XRD diffractogram, lower crystallinity was observed at the 2 theta values of 22.6 and 16.1 for PANi/CNC compared to that for pure CNC. The FESEM images showed high porosity of the nanostructure with no phase separation, revealing the homogenous polymerization of the monomer on the surface of the crystalline cellulose. Aggregation of PANi particles was observed with the increasing aniline concentration

Evaluation of factors influencing the groundwater chemistry in a small tropical island of Malaysia.

Groundwater chemistry of small tropical islands is influenced by many factors, such as recharge, weathering and seawater intrusion, among others, which interact with each other in a very complex way. In this work, multivariate statistical analysis was used to evaluate the factors controlling the groundwater chemistry of Kapas Island (Malaysia). Principal component analysis (PCA) was applied to 17 hydrochemical parameters from 108 groundwater samples obtained from 18 sampling sites. PCA extracted four PCs, namely seawater intrusion, redox reaction, anthropogenic pollution and weather factors, which collectively were responsible for more than 87% of the total variance of the island’s hydrochemistry. The cluster analysis indicated that three factors (weather, redox reaction and seawater intrusion) controlled the hydrochemistry of the area, and the variables were allocated to three groups based on similarity. A Piper diagram classified the island’s water types into Ca-HCO3 water type, Na-HCO3 water type, Na-SO4-Cl water type and Na-Cl water type, indicating recharge, mixed, weathering and leached from sewage and seawater intrusion, respectively. This work will provide policy makers and land managers with knowledge of the precise water quality problems affecting the island and can also serve as a guide for hydrochemistry assessments of other islands that share similar characteristics with the island in question

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance.

Investment in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing in Africa over the past year has led to a major increase in the number of sequences that have been generated and used to track the pandemic on the continent, a number that now exceeds 100,000 genomes. Our results show an increase in the number of African countries that are able to sequence domestically and highlight that local sequencing enables faster turnaround times and more-regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and illuminate the distinct dispersal dynamics of variants of concern-particularly Alpha, Beta, Delta, and Omicron-on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve while the continent faces many emerging and reemerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Developing an Electronic Device to Teach English as a Foreign Language: Educational Toy for Pre-Kindergarten Children

This Educational toys are important in early child development and motivate children to learn language. Numerous digital toys are now available in the children’s educational toys market to help children learn foreign languages. However, a number of such technologies are expensive and the quality of usability is not at an acceptable level. The aim of the study is to develop a cost-effective, sustainable and danger-free educational toy for pre-kindergarten children aged between 4-5 years old to teach English as a second language in developing countries. This toy has been developed with Raspberry Pi and makes use of the RFID technology. The experiment in this research was conducted with 20 pre-kindergarten children for four weeks under the supervision of 14 teachers, using five games of the developed toy testing the pre-kindergarten children’s learning of alphabet, words, colors, shapes, and numbers. A design-based research model with an innovation design method utilized during the development stage of the toy. Quantitative and qualitative methods were used to evaluate the developed toy. The results of the experiment showed that the developed toy is user-friendly, and the pre-kindergarten children were enthusiastic about playing with it and learning was enjoyable. Also, the results showed that the developed toy can be suitable for use as an educational toy for pre-kindergarten children to teach English as a second language. The educational toy developed by the researchers will be beneficial for those who wish to teach English to pre-kindergarten children such as administrators, teachers and parents in developing countries