Multimedia University of Kenya

In this paper, we present a theoretical analysis for a coherent switch between electromagnetically induced transparency (EIT) and electromagnetically induced absorption (EIA) for N-type atomic system. The coherent switch is due to the induced atomic coherence, which depends on the intensity of coupling pump lasers. For atomic vapor at a finite temperature, the EIT-EIA switch is lost due to Doppler overlaps, however, a EIA dip is induced on the transparency spectrum of the probe. Additionally, a switch between transparency and enhanced absorption for N-type configuration is due to coherence effect causing EIT and optical pumping effect (a source of ground state levels population dynamics), both effects also depends on the intensity of the blue pump lasers.

This study examines the role of internet memes in digital activism for political accountability in Kenya, focusing on the #RejectFinanceBill2024 and #OccupyParliament campaigns. Using a qualitative research design, the study analyzed 500 political memes from TikTok and X (formerly Twitter) alongside semi-structured interviews with 182 participants including digital activists, meme creators, policymakers, and political analysts. Grounded in Networked Publics Theory and Framing Theory, the research investigated how memes simplify complex policy issues, shape political discourse, mobilize citizens, and interact with platform dynamics. Findings reveal that satirical images and video memes (62% of content) effectively framed political leaders as accountable for governance failures, while viral political jokes (24%) and remix culture (14%) enhanced engagement through cultural resonance. The study demonstrates that memes function as powerful instruments of digital resistance, generating public pressure (74% of cases) and government responsiveness (58%), though their impact on sustained policy reform remains limited. Platform algorithms significantly influenced visibility, with TikTok's For You Page amplifying protest content to wider audiences compared to X's reported content suppression. The research concludes that while memes successfully mobilize episodic activism and shape public opinion, translating online momentum into structural accountability requires complementary offline advocacy strategies and transparent platform governance frameworks.

Water heating is increasingly becoming one of the major energy-consuming activities in Kenya and globally. This trend is largely driven by significant efficiency improvements in other energy consuming sectors such as lighting and household appliances, while heating technologies have experienced relatively minimal advancements. Although electric water heaters are efficient, their adoption in institutions such as Multimedia University (MMU) has declined due to several challenges, including high electricity costs, high maintenance costs associated with elevated chlorine levels in water, carbon dioxide (CO2) emissions from grid electricity, and national trade imbalances linked to the importation of heavy fuel oil used in non-renewable electricity generation. This study evaluates the techno-economic feasibility of replacing electric immersion heaters with evacuated tube solar collectors (ETCs) for large-scale water heating at MMU’s executive hostel, serving over 300 users. Water consumption patterns were monitored over one week, revealing an average usage of 49.1 L per person per bath and a total daily demand of 15,529.6 L, corresponding to an energy demand of 400.48 kWh/day. RETScreen Expert software was used to simulate and optimize the solar thermal system using a site solar radiation of 5.32 kWh/m2/day and collector parameters Fr(τα)=0.68 and FrUL=1.33. The results indicate that immersion heaters currently consume 175,200 kWh annually at a cost of $31,658.51 and generate 8,628.7 kg of CO2 emissions per year. The optimal ETC system achieves a 64% solar fraction with a collector capacity of 21,300 L, a tilt angle of 15°, and storage of 75 L/m2. Economic analysis at a nominal discount rate of 10.75% yields a net present value of $29,083.96, an internal rate of return of 24%, and a payback period of less than three years, demonstrating the strong economic viability of solar water heating for institutional applications.

Electronic tendering (e-tendering) has become an integral component of digital procurement systems due to its potential to improve procurement efficiency, transparency, accountability, and overall organizational performance. Despite continued investments in electronic procurement technologies by county governments in Kenya, procurement performance remains below expectations, as evidenced by procurement delays, high transaction costs, limited transparency, procurement disputes, and inefficiencies in supplier selection and contract award processes. Nairobi City County Government continues to experience procurement challenges despite implementing electronic tendering through the Integrated Financial Management Information System (IFMIS). Existing empirical studies have largely concentrated on the general adoption of e-procurement while providing limited evidence on the specific contribution of e-tendering to procurement performance within county governments in Kenya. This study therefore examined the effect of electronic tendering on procurement performance in Nairobi City County Government. The study was anchored on the Technology Acceptance Model (TAM) and employed a descriptive research design. The target population comprised employees involved in procurement-related functions within Nairobi City County Government. Primary data were collected using structured questionnaires, while Statistical Package for Social Sciences (SPSS) version 26 was used to generate descriptive and inferential statistics. Diagnostic tests were conducted to confirm compliance with the assumptions of regression analysis before hypothesis testing. Descriptive statistics indicated that respondents generally agreed that electronic tendering had enhanced transparency, improved supplier participation, accelerated procurement processes, and strengthened fairness in tender evaluation and award. Regression analysis further established that electronic tendering had a positive and statistically significant effect on procurement performance (β = [insert standardized beta], p < 0.05), leading to the rejection of the null hypothesis. The findings demonstrate that effective implementation of electronic tendering significantly enhances procurement performance by reducing procurement cycle time, improving transparency, increasing operational efficiency, and promoting value for money. The study concludes that electronic tendering is a critical digital procurement practice for enhancing procurement performance within county governments. The study recommends that Nairobi City County Government should strengthen electronic tendering infrastructure, enhance staff capacity through continuous training, improve system integration, and formulate policies that encourage full compliance with electronic tendering procedures to maximize procurement performance. Keywords: Electronic Tendering, E-Procurement, Procurement Performance, Digital Procurement, Public Procurement, Nairobi City County Government, Kenya

This study aimed to determine the adsorption Isotherms, kinetics and thermodynamic parameters of lead (Pb²⁺) chromium (Cr3+) and cadmium (Cd2+) ions from aqueous solutions using developed magadiitic aluminosilcate nanozeolite. The analyses were performed and evaluated by using liquid - solid phase extraction method with adsorbent system at optimal conditions. These conditions were, pH, adsorbent dosage, concentration, temperatures and contact time for adsorption of the analytes from the aqueous solutions onto the adsorbent were optimized at 5, 0.02 g, 25 ppm, 25°C and 15 minutes respectively. An Inductively Couple Plasma Emission spectrometer (ICPE – 9800 series Shimadzu) was used for the measurement of the emission intensities of Pb²⁺, Cr3+ and Cd2+ ions. Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models respectively were implemented to equilibrium results obtained. Experimental and theoretical monolayer adsorption capacities of the adsorbent adsorption of Pb²⁺, Cr3+ and Cd2+ ions by Langmuir Isotherm model also fitted the data well, with a maximum adsorption capacity of 37.88 mg/g, 8.53 mg/g and 9.56 mg/g respectively at 25°C. The most appropriate kinetics model from analysis of the adsorption mechanisms revealed that the process was best described by the Temkin Isotherm model, Pseudo-Second-Order kinetic model, indicated that chemisorption was the rate-limiting step. Thermodynamic values, Gibbs free energy (ΔGo), enthalpy changes (ΔHo), entropy change (ΔSo), were determined and assessed. Furthermore, thermodynamic studies confirmed that the adsorption of Pb²⁺, Cr3+ and Cd2+ ions onto the nanozeolite was a spontaneous and exothermic process. The Langmuir model’s high maximum adsorption capacity of 37.88 mg/g, for Pb²⁺, confirmed the material's strong affinity for lead ions.