Growth kinetics of environmental Legionella pneumophila isolated from industrial wastewater

Wastewater treatment plants are environmental niches for Legionella pneumophila, the most commonly identified causative agent of severe pneumonia known as Legionnaire's disease. In the present study, Legionella pneumophila's concentrations were monitored in an industrial wastewater treatment plant and environmental isolates were characterized concerning their growth kinetics with respect to temperature and their inhibition by organic acids and ammonium. The results of the monitoring study showed that Legionella pneumophila occurs in activated sludge tanks operated with very different sludge retention times, 2.5 days in a complete-mix reactor, and 10 days in a membrane bioreactor, indicating that this bacterium can grow at different rates, despite the same wastewater temperature of 35 degrees C. The morphology of Legionella cells is different in both reactors; in the membrane bioreactor, the bacteria grow in clusters, while in the complete-mix reactor, filaments predominate demonstrating a faster growth rate. Legionella pneumophila concentrations in the complete-mix reactor and in the membrane bioreactor were within the range 3 x 10(1) to 4.8 x 10(3) GU/mL and 3 x 10(2) to 4.7 x 10(3) GU/mL, respectively. Environmental Legionella pneumophila SG2-14 isolates showed distinct temperature preferences. The lowest growth rate was observed at 28 degrees C, and the highest 0.34 d(-1) was obtained at 42 degrees C. The presence of high concentrations of organic acids and ammonium found in anaerobically pre-treated wastewater caused growth inhibition. Despite the increasing research efforts, the mechanisms governing the growth of Legionella pneumophila in wastewater treatment plants are still unclear. New innovative strategies to prevent the proliferation of this bacterium in wastewater are in demand

Thermoelectric and Magnetothermoelectric Transport Measurements of Graphene

The conductance and thermoelectric power (TEP) of graphene is simultaneously measured using microfabricated heater and thermometer electrodes. The sign of the TEP changes across the charge neutrality point as the majority carrier density switches from electron to hole. The gate dependent conductance and TEP exhibit a quantitative agreement with the semiclassical Mott relation. In the quantum Hall regime at high magnetic field, quantized thermopower and Nernst signals are observed and are also in agreement with the generalized Mott relation, except for strong deviations near the charge neutrality point

Econometric Data Analysis Affecting Performance of Supply Chain Systems in the Petroleum Industries in Kenya

The purpose of this paper was to do econometric data analysis on performance of supply chain systems in the petroleum industries in Kenya. Specifically, the objectives of the study were to establish whether there is any effect from; level of skills, information and communication technology and tendering systems and the moderating factor have an effect on supply chain systems performance. The study was conducted using a survey design. The total population of all oil companies in the 73 was covered by the study.  Several studies were carried to validate the final findings. Finally, this statistics concluded that there is need to do econometric data analysis to validate the effect of supply chain systems on performance by doing proper forecasting from the up streams to the down streams towards achieving a competitive edge in the business markets such as the petroleum industry. The econometric analysis focused on the these areas;  Information functions in order to inform management, support decision making and to identify  problem areas; Steering function in order to set targets and give directions to desired outcomes; Controlling function in order to supervise process execution. Keywords: level of skill of staffs, Information communication and technology, Tendering systems and Performanc

Influence of Liquidity on Financial Performance of Insurance Companies in Kenya

Liquidity is the capacity of a company to satisfy its current financial obligations after they fall due.  A firm may incur extra costs if it fails to honor its short term financial obligations. The aim of the study was to determine the influence of liquidity on the financial performance of insurance companies in Kenya. The research applied a correlational research design. A correlational study design is administrated to debate the connection between variables. The target population for this study was the fifty-three insurance companies in Kenya that were operational in 2018. The investigation found that liquidity had an enormous positive effect on financial performance  (Return on assets and return on equity). The study concludes that the greatest threat to liquidity  may occur in an insurance firm during a catastrophe when a large number of claims are received  directly or there could even be prospects of a significantly large claim which insurance companies  should have optimal liquidity for such situations. The review recommends that Insurance firms should monitor liquidity in their firms and adopt corrective actions in instances of high liquidity risk.&nbsp

Determinant Affecting Performance of Supply Chain Systems in the Petroleum Industries in Kenya

The purpose of this paper was to analyze the effect of crude oil price as a determinant on performance of supply chain systems in the petroleum industries in Kenya. Supply chain is a dynamic process and involves the constant flow of information, materials, and funds across multiple functional areas both within and between chain members. Members in the chain need to cooperate with their business partners in order to meet customer’s needs and to maximize their profit by reducing cost of crude oil. However, it is a very difficult task in managing the multiple collaborations in a supply chain because there are so many firms involved in the supply chain operations with its own resources  processes also requires real-time operation and decision making across different tasks, functional areas, and organizational boundaries in order to deal with problems and uncertainties. The strategic move of focus for mass customization, quick response, and high-quality service cannot be achieved without more complex cooperation and dynamic structure of supply chains. Keywords: Cost of crude oil price, and Performance of supply chai

Income Diversification and Intermediation Efficiency: Evidence from Deposit Taking Sacco Societies in Kenya

Research on the relationship between diversification into nontraditional income streams and firm efficiency is scanty. The study seeks to fill the gap by evaluating the relationship between diversification into non interest income and intermediation efficiency of Deposit Taking Sacco Societies (DTSs) in Kenya using a two staged methodology. In the first stage, efficiency scores are generated using Data Envelopment Analysis (DEA), corrected for bias using bootstrapping and used as dependent variable in the fixed effect regression model estimated in the second stage. A balanced panel data of 103 DTSs for a period 2011-2014 was used in the study. The results showed that there exists an inverse relationship between the ratio of noninterest income to total assets and intermediation efficiency. This implied that diversification hurts efficiency. Keywords: Data Envelopment Analysis, Deposit Taking Sacco, Diversification, Intermediation Efficiency, Noninterest income

Keragaman Genetik Plasma Nutfah Rambutan di Indonesia Berdasarkan Karakter Morfologi

Rambutan merupakan tanaman menyerbuk silang sehingga secara alami memiliki keragaman tinggi. Penelitian bertujuan mempelajari kemiripan genetik dan pengelompokan aksesi plasma nutfah rambutan (Nephelium lappaceum) dan kapulasan (Nephelium ramboutan-ake) di Indonesia berdasarkan karakteristik morfologi. Penelitian dilakukan di (1) Kebun Percobaan (KP) Aripan Balai Penelitian Tanaman Buah Tropika, (2) KP Subang Balai Penelitian Tanaman Buah Tropika, (3) KP Cipaku Balai Pengkajian Teknologi Pertanian Jawa Barat, dan (4) Kabupaten Limapuluh Kota (Sumatera Barat), pada bulan Juni 2013 sampai Februari 2014. Karakterisasi sifat morfologi dilakukan terhadap 29 aksesi rambutan dan empat aksesi kapulasan mengacu pada descriptor for rambutan yang diterbitkan IPGRI. Perhitungan koefisien ketidakmiripan antaraksesi dilakukan dengan metode Gower. Analisis nominal logistic biplot dilakukan untuk melihat sifat penciri dari suatu kumpulan aksesi. Analisis keragaman genetik dapat membedakan kelompok rambutan dan kapulasan dengan koefisien ketidakmiripan rerata sekitar 55%. Berdasarkan kerapatan tandan, rambutan dapat dikelompokkan menjadi lima kelompok, yaitu aksesi yang memiliki tandan sangat jarang, jarang, sedang, rapat, dan sangat rapat. Aksesi dengan tandan rapat sampai sangat rapat antara lain aksesi Gendut Kair, Tangkue, dan Aceh Gendut, sedangkan semua aksesi kapulasan memiliki tandan yang sangat jarang. Berdasarkan ketebalan kulit buah, semua aksesi rambutan memiliki ketebalan kulit sedang sampai tebal, sedangkan aksesi Sibabat diketahui memiliki kulit yang sangat tebal

Effect of Attitude Towards Risk on Individual Portfolio Choice at the Nairobi Securities Exchange, Kenya

Attitude towards riskplays a major role of determining a portfolio choice of an investment portfolio composed of a single or multiple assets that an investor chooses within a certain period of time. Although there exist numerous controversial arguments of the factors that determine the level of individual portfolio choice, focus on multidimensional perceptions of investors characteristics have been given little attention. The objective of this study was to determine the effect of investor’s attitude towards risk on individual portfolio choice at the Nairobi securities exchange and  to investigate the moderating effect of investor’s age on the correlation between attitude towards riskand individual portfolio choice on common stocks at the Nairobi securities exchange. The study is anchored on risk aversion theory. A correlational research design was used for collecting data for the variables under study over a period of five years from January, 2013 to December, 2017. The population consisted of individual investors estimated at 2.4 million as at 31st December 2017 based on Central Depository and Settlement Corporation Limited (CDSC). A target population of 997,605 active retail investors who also form the accessible population at Nairobi securities exchange(NSE) were used to draw a sample size of 385 active individual retail investors. Both stratified and convenience sampling was used to select the required number of respondents. A structured questionnaire was used to collect the data whereby drop and pick approach was used by the researcher and research assistants. Pilot testing of the instruments was performed to assess its reliability. Further, multiple regression techniques were used to analyze the data obtained that was presented using frequency tables, means, standard deviations and correlation tables. The study findings revealed that attitude towards risk, have a positive and significant effect on the common stocks. As such a unit increase in a predictor variable leads to an increase in investment in common stocks. Further, the results of the study indicated that age moderate the relationship between attitude towards risk and the individual portfolio choice in respect to common stocks. The study will benefit management of investment banks and brokerage firms in policy formulation to assist individual investors in their portfolio choices and also to the academicians to advance the conceptual arguments of the moderating effect of age on the relationship between attitude towards risk and individual portfolio choice. Keywords: Attitude towards risk, Individual portfolio choice, Risk aversion,Investor’s age. DOI: 10.7176/RJFA/13-20-01 Publication date:October 31st 202

Aplikasi Media Pembelajaran Pengenalan Rambu Lalu Lintas Menggunakan Flash

Traffic signs are important parts of street equipments which consist of attributes, letters, numbers, sentences and can be the combinations of all in order to help street users. But in the reality there are still a lot of traffic accidents happen because of the lack of understanding about the traffic signs by the vehicles drivers and pedestrians.There are so many informations about traffic signs from media, such as books, advertising and seminars from the police department, but those media are considered ineffective, not interesting and less interactive.Consequently, a learning media application is made by using Adobe Flash so it can help other people to be more attracted to learn about traffic signs. This application have informations about the meaning of the traffic, theoretics questions that has been used to get a driving license, pratice test to get a driving license and driving game simulation.From the result of the experiment, this application can help users in understanding the traffic signs and can convince them to reuse this application. At the process of friendly use to apply this application, not all users directly understand on how to use it