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Investigation of Pesticidal and Insecticidal Activity of Essential Oil Extracted from Selected Local Plants (Juniper Procera and Aloe Vera Leaves)
No full textThis study aimed to investigate the pesticidal and insecticidal activities of essential oils extracted from locally available Juniper procera and Aloe Vera leaves against cochineal and cockroach insects. The essential oils were extracted using Soxhlet extraction. To determine the optimal conditions for maximum essential oil yield, the study evaluated a range of temperatures (70°C 90°C), particle sizes (<0.5mm – 4mm), and extraction times (4hr–6hr). The maximum yield obtained for Juniper procera leaves essential oil was 4.5% under optimal conditions of 80.01°C, 5.82 hours of extraction time, and a particle size of 0.5mm. For Aloe Vera leaves essential oil, the maximum yield was 23.33%, obtained with a particle size of less than 0.5mm, a temperature of 80°C, and an extraction time of 4.5 hours. The pesticidal and insecticidal activities of Juniper procera and Aloe Vera leaves essential oils, as well as their mixture, were investigated against cochineal insects (cactus pests) and cockroaches. The study evaluated the effect of essential oil concentration and exposure time on the mortality of both insect types. For each essential oil and the mixture, the same concentrations were applied to the selected insects, and mortality was observed at 1, 2, and 3 days post application. The results indicated that Juniper procera essential oil exhibited slightly better pesticidal activity against cochineal insects, with lethal concentrations (LC50 and LC90) of 4.52 b mg/ml and 18.06 mg/ml, respectively. The mixture of both essential oils showed intermediate activity (LC50 = 6.52 mg/ml, LC90 = 20.76 mg/ml), while Aloe Vera essential oil demonstrated the least activity against cochineal insects (LC50 = 7.98 mg/ml, LC90 = 22.72 mg/ml). Similarly, Juniper procera essential oil displayed slightly superior insecticidal activity against cockroaches (LC50 = 3.20 mg/ml, LC90 = 9.12 mg/ml), followed by the essential oil mixture (LC50 = 4.31 mg/ml, LC90 = 10.40 mg/ml), and then Aloe vera essential oil (LC50 = 5.08 mg/ml, LC90 = 11.85 mg/ml)
Distributed Power Flow Controller Based Power Quality Improvement for Grid Connected Wind Farm- Case Study Ashegoda Wind Farm
No full textGrid penetration level of renewable energy is growing and merging dramatically. However, poor power quality creates a major integration and operation problems. Ashegoda wind farm represents Ethiopian first large scale wind power installation, having a total rated capacity of 120 MW. The substation is equipped with two 230kv buses that interconnect Lachi and Alamata substations. In the analyzed system, both transmission lines experienced high reactive power flow approximately 43MVAr and more than 3% current total harmonic distortion (THD), which leads to additional power loss, voltage drop, equipment overheating, and network congestions. On the other hand, the on-load tap changer (OLTC) transformer used to support voltage sag, swell, under-voltage, and over-voltage has slow response time up to 10 seconds per tap, and creates transformer overheating and mechanical fatigue. To solve such integration challenges, the incorporation of a distributed power flow controller (DPFC) with in the system is necessary for improved power quality and reliability. This study analyzed and modeled the integration, impact, cost benefit analysis, and Genetic Algorithm (GA) based optimal sizing and placement of DPFC for Ashegoda wind farm. The objective was to model, simulate, and asses its impact on voltage stability, reactive power compensation, and steady state and dynamic performance. The result indicated that, without DPFC the 230kv system operated at under-voltage of 0.89 pu with 5% current THD at bus 690v. After integration of 8MVA series and 25MVA shunt DPFC controller, the voltage profile is improved to 0.96 pu and current THD is minimized to 1.8%. Integrating DPFC exhibited excellent performance in maintaining voltage stability and limiting short-circuit current levels under different fault scenarios. The cost benefit analysis was carried out over a 20-year period. The total net present value (NPV) is estimated around 7,883,000.00 US dollars. By implementing the system, Ethiopian electric utility is expected to gain $7.5 million US dollars profit without considering scrap value. Generally, the researcher proved that DPFC is technically and economically feasible. MATLAB/Simulink 2018a and Excel-2013 was employed to model, simulate, and analyze the proposed DPFC system
THE PRACTICE OF COMMUNITY PARTICIPATION IN SCHOOL GOVERNANCE፡THE CASE OF SECONDARY SCHOOLS IN CENTRAL ZONE OF TIGRAY REGIONAL STATE
No full textThe objective of the present study was to investigate the practice of community participation in school governance-in case of secondary schools in Central Zone of Tigray Regional State. Descriptive survey design was applied using both quantitative and qualitative approaches. A total of 217 participants were computed using Abera, (2013) principle and were taken with a combination of purposive and simple random sampling techniques. Pretested Data were gathered using Questionnaire and interview and was analyzed using percentage and mean calculated through SPSS using likert scales. The finding of the current study highlights that the participation of community representatives in instructional programs was not encouraging. However, the community participation was challenged by number of factors like Poor economic background of community representatives; lack of skill, knowledge and poor understanding of their roles and responsibilities of community representatives and negative attitude of the principals towards participation of community, lack of well-developed school rules, regulation, norms and no appropriate strategy for the school to encourage and provide community services, information about school management, Low teacher commitment. Therefore, the school principals of the study area must developed basic ground school rules, regulation and appropriate strategy that leads school communities’ to participate in their school management
Investigating the prevalence and risk factors of cystic echinococcosis in humans and slaughtered cattle in peri-urban dogowning smallholder farms in Mekelle zone, Tigray Region, Northern Ethiopia
No full textBackground: Cystic Echinococcosis (CE), a zoonotic disease caused by the larval stage of Echinococcus granulosus, poses significant public health and economic challenges in Ethiopia. Despite its impact, data on its prevalence in humans, slaughtered cattle, and dogs particularly in the Tigray Regional State, remain limited.
Objective: Investigating the prevalence and risk factors of cystic echinococcosis in humans and slaughtered cattle in peri-urban dog- owning smallholder farms in Mekelle zone, Tigray Region, Northern Ethiopia.
Method: A cross-sectional study was carried out from March 2024 to March 2025 involving 832 human participants, 212 cattle, and 384 dogs. Human participants were selected using a stratified sampling technique, while the peri-urban smallholder farms owning dogs were purposively selected in the Mekelle Zone. Hydatidosis screening was performed using abdominal ultrasound, and laboratory analysis was conducted on specimens from slaughtered cattle and fecal samples from their dogs. Microscopic examination (40×) was used to detect hydatid cysts in cattle and taeniid eggs in dog feces. Data were analyzed using SPSS version 27, applying descriptive statistics and logistic regression to identify factors associated with CE at a significance level of p < 0.05.
Result: The overall prevalence of CE from six purposively selected sub-districts of Mekelle zone was found to be 0.24% (2/832) in humans, 22.64% (48/212) in cattle, and 17.45% (67/384) in dogs. The two human cases involved a 45-year-old male, and 50-yearold women. In cattle, distribution of cysts was primarily found (68.75%) in the lungs and (25.0%) in liver and (2.08%) each in the kidneys, heart, and spleen. Fertility and viability in cattle (68.8%) in lungs and (25.0%) in liver. CE prevalence was higher in male cattle (24.52%) than in females (16.0%), and poor body condition (40.0%) compared to those with medium (22.45%), and good (17.07%). Backyard-slaughtered cattle had a higher infection rate (34.69%) than those slaughtered in abattoirs (19.01%). Factors significantly associated with CE in cattle included age, sex, body condition, and slaughter location (p < 0.05). In the multivariate logistic regression analysis adult cattle (AOR = 2.57; 95% CI:1.501,4.400; P = 0. 001), cattle with poor body condition score (AOR = 4.07; 95% CI: 2.177,7.618; P = 0.000), and cattle slaughtered at backyard slabs (AOR = 2.26; 95% CI: 1.300,3.940; P = 0.004) were more likely to acquire hydatid cysts than the others. After adjusting for potential confounders, dogs with stray roaming behavior (AOR = 2.93; 95% CI: 1.11–7.71; p = 0.029) and feed raw offal (AOR = 2.86; 95% CI: 1.38–5.93; p = 0.005) had significantly higher odds of CE infection.
Conclusion: The present study showed that CE is a considerably prevalent disease in human, cattle and dogs in the study area. This emphasizes the need to avoid backyard slaughter practice, unsafe offal feeding of dogs, and proper waste disposal which requires public awareness on the use of abattoirs
DETERMINANTS OF PREMATURE RUPTURE OF MEMBRANES AMONG PREGNANT MOTHERS ATTENDING PUBLIC HOSPITALS OF CENTRAL ZONE, TIGRAY, ETHIOPIA, 2024; UNMACHED CASE-CONTROL STUDY
No full textBackground: Premature rupture of membranes is a condition in which the fetal membranes rupture before the onset of labor and after 28 weeks of gestational age. It complicates 5-10% of all pregnancy, and it is an important cause of perinatal, neonatal, and maternal morbidity and mortality both in developed and developing countries. Though some studies were conducted in Ethiopia on the determinants of premature rupture of membranes there was limited study in the Tigray region, particularly in the study area
Objective: To identify determinants of premature rupture of membranes among pregnant mothers admitted to public hospitals in the Central Zone, Tigray, Ethiopia,2024
Methods: A hospital based unmatched case-control study design was conducted from August 1 to September 30, 2024, in public hospitals of Central Zone of Tigray, Ethiopia. All cases admitted at the time of data collection were included until the desired sample size was met, and controls were selected by systematic random sampling. Data were collected using a structured and pre-tested questionnaire by trained midwives then data were entered into Epi Data Version 4.7 and exported to Statistical Package for Social Sciences Version 27. Logistic regression was employed to identify determinant variables. Variables with a p value of less than 0.05 with a 95% confidence interval were used as a statistically significant association in a multivariable logistic regression.
Result: A total of 363 participants (121 cases and 242 controls) were included in the study. Rural residence (AOR=2.17,95 % CI: 1.31-3.59, p-value=0.003), having multiple fetus (AOR=2.44,95% CI: 1.01-5.89, p-value=0.047), history of Premature rupture of membrane (AOR=2.76,95% CI: 1.42-5.38, p-value=0.003), and Mid-upper arm circumference <23cm (AOR=2.79,95% CI: 1.59-4.89, p-value=0.001) were identified as determinants of premature rupture of membrane.
Conclusion and recommendation: The identified determinants of premature rupture of membranes were rural residence, multiple gestation, history of Premature rupture of membrane, and Mid-upper arm circumference <23 cm. Therefore, pregnant women who live in rural areas, have multiple pregnancy and had history of premature rupture of membranes should be well followed up during pregnancy. Moreover, early nutritional screening, counseling and intervention should be strengthened during prenatal care
EXAMANING THE POST WAR HERITAGE LANDSCAPE: A COMPREHENSIVE STUDY OF TOURISM DEVELOPMENT IN ROCK HEWEN CHURCHES OF GHEREALTA CLUSTER, TIGRAI, ETHIOPIA
No full textThis research examines the post-war heritage landscape of the GRHCs in Tigray, Ethiopia, focusing on the impact of conflict on the tourism sector and exploring strategies for recovery and sustainable development. The region, home to a collection of ancient and culturally significant churches, has faced severe damage from the recent conflict, resulting in a decline in heritage preservation and tourism. The study's primary objective is to understand the challenges and opportunities for revitalizing the tourism industry in Gherealta by addressing key aspects such as infrastructure, community involvement, heritage conservation, and sustainability.
The study’s methodology combines qualitative and quantitative research approaches, including interviews with local stakeholders, tour guides, and hotel operators and surveys from tourists and local community members. The research aims to answer critical questions related to the physical and intangible damage to the churches, the role of the local community in post-conflict tourism, the infrastructural barriers to tourism development, and the strategic measures needed for long-term sustainability.
The findings of the study reveal significant challenges, including the widespread damage to the churches, deteriorated infrastructure, and a lack of local engagement in the tourism sector. Additionally, security concerns and a lack of resources have contributed to a sharp decline in tourist numbers. The study identifies several key strategies to address these challenges, including the restoration and preservation of rock-hewn churches, infrastructure development, the promotion of community-based tourism initiatives, and the implementation of sustainable tourism practices. Collaboration with international heritage organizations such as UNESCO and the establishment of public-private partnerships are also highlighted as essential steps for recovery.
The research concludes by emphasizing the need for a comprehensive, multi-dimensional approach to tourism development that balances heritage conservation with community empowerment and sustainable growth. By integrating advanced technologies, fostering regional and global collaborations, and ensuring continuous research and monitoring, Gherealta can transition from a post-conflict recovery phase to a thriving cultural tourism destination. This study provides a roadmap for the revitalization of Gherealta, offering actionable recommendations that can serve as a model for other war-affected heritage site
The steady-state squeezing and entanglement properties of the cavity radiation from parametric oscillation
No full textIn this thesis, we study the quantum properties of the light generated by a para metric oscillation with the cavity mode driven by coherent light beams coupled to a two-mode squeezed vacuum reservoir. Applying the master equation describing the interaction of the cavity modes with the driving coherent light beams and with the two-mode squeezed vacuum reservoir, we obtain the quantum Langevin equations. The solutions of the resulting equations are then used to calculate the mean and vari ance of the photon number, the quadrature variance, global quadrature squeezing and local quadrature squeezing of two-mode cavity light. It is found that the squeezing occurs in the plus quadrature and the driving coherent light beams have no effect on the squeezing properties of the two-mode cavity light. We have found that, at steady state and at threshold, there is a maximum squeezing of the two-mode cavity light when the cavity is coupled to squeezed vacuum reservoir. In general, the degree of squeezing increases with the squeezed parameter whereas the driving coherent light beams and the squeezing parameter have the effect of increasing the mean photon number of the two-mode cavity light.Content
Sexual Objectification of Women in Modern Tigrinya Music Videos: A Case Study of Engdot Sembet on Dimtsi Weyane TV
No full textThis study explores the sexual objectification of women in modern Tigrigna music videos, particularly those broadcast on Dimtsi Weyane TV. Employing a qualitative research approach, the study uses content analysis as its primary method to assess how women are portrayed visually and thematically in 25 selected music videos. In addition, interviews were conducted with key individuals involved in the selection and broadcasting of these videos to understand the underlying factors contributing to the inclusion of objectifying content. Findings reveal that women are frequently depicted in sexually suggestive clothing, submissive roles, and as accessories to male-centered narratives. Despite the pervasive objectification, hosts and producers of the program often overlook these portrayals, focusing instead on other themes such as lyrical content, political or religious sensitivity, or cultural messages. This lack of awareness underscores a critical gap in content evaluation processes within the media outlet. The study concludes that modern Tigrigna music videos broadcast on Dimtsi Weyane TV contribute to the normalization of the sexual objectification of women. It calls for increased awareness among content curators, the development of gender-sensitive media guidelines, and further research to address the broader implications of media portrayals on societal gender norms
INSTRUCTIONAL SUPERVISION ROLE OF PRINCIPALS AND ITS` INFLUENCE ON STUDENTS’ ACADEMIC ACHIEVEMENT IN GOVERNMENT SECONDARY SCHOOLS OF WOLKAIT WOREDA
No full textThe purpose of the study was to determine “instructional supervision role of principals and its influence on students’ academic achievement in governmental public secondary schools of Welkait woreda”.The study used both mixed method which were qualitative and quantitative approaches. Quantitative approach was used to collect data about magnitudes of numeric amounts and qualitative approach was used to collect data of perceptions by using narrative methods. The design of the study was descriptive survey stressing standard sets of tools such as questionnaire, interview and document analysis to triangulate the data from many sides of the evident sources. The data of questionnaire was performed by using tallied system tabulating its scores and the scores were entered in to SPSS software using version20 to analyze by using mean. Independent sampling ttest of inferential statistics was used. Interview was analyzed using statements taking common collective ideas from the interviewees. Finally, documents were checked according to the prepared questions of check lists and the data was analyzed as a summarized point in the form of narration or statement to crosscheck past event of instructional supervision role of principals conducted in secondary schools. The samples included in the study were: 207 in number whom were sampled from the population of students, teachers, principals, vice principals’ department heads and cluster supervisor. The samples were taken by purposive, comprehensive, stratification and systematic randomization way of sampling. Finding of the study was: the role of principals’ instructional supervision has influence on students’ academic achievement. Conclusion of the study shows that when the role of principal increases, student achievement also increases. If the role of principal decreases, student achievement decreases. Thus, achievement is dependent variable and principals’ role is independent variable. Knowledge gravity is mind of the students and students are academic beneficiary of the curriculum. Again, principal is a center of experience but not source of experience this shows a principal gathers experience from teachers and shares to teachers. In addition of this, supervision is not the end of principals’ role rather it is a means to student achievement. Thus, student employment is outcome of supervisory role. Challenges released by respondents as examples were: administrative supervision and instructional supervision were conducted in once period of supervising time as mixed work and complex to give feedback for those together. Recommendation about the problem was; instructional supervision should be separated from administrative task during academic supervisor to give sufficient feedback to teachers to share best experience conducting individual and collective feedback using the role of principals focusing on students’ academic achievement. Again, individual feedback of teachers can minimize supervision resistance than giving collective post supervision feedback
ዕሊማ ምእታውን ግቡእነትኣቀራርባን ስነቃሊት መፅሓፍ ተምሃራይ ትግርኛ ታሽዒይ ክፍሉ
No full textማራ ሓሳብ
እዙ መፅናዕቲ ኣብ ዕሊማ ምእታውን ግቡእነት ኣቀራርባን ስነቃሊት መፅሓፍ ተምሃራይ ትግርኛ
ታሽዒይ ከፍሉ ኮይኑ ብዋናነት ኣብዙ ዜኣተዉ ስነቃሊት ንምንታይ ዕሊማ ከምዜኣተዉን ግቡእነት
ኣቃራርበኦም እንታይ ከምዜመስሌ ብምፍታሽ መፅናዕቲ ተኻይደ እዩ፡፡ እዙ መፅናዕቲ ንምክያዴ
መበገሲ ዜኾነ ሓሳብ ኣብ ከይዱ ምምሃር ምስትምሃር ቋንቋ ትግርኛ ንምምሃር ዜኣተዉ ስነቃሊት
ትኹረት አይግበረልምን ብዕሊማ ኣይኣተዉን ዜብሌ ሓሳብ ስሇ ዜቐርብን ነዙ ንምርግጋፅ ኣብ ተግባር
ዜወዒሇ ዕሊማን ግቡእነት አቀራርብኡን ንምትንታን እዩ ፡፡ሜሊ ኣፀናነዒ ዴማ ኣገዯስቲ ሕቶታት
ዜምሌሱ ካብ መፅሓፍ ተምሃራይ ዲህሳስንዕምቆታዊ ንባብ መረዲእታ ተኣኪቦም እዮም ፡፡ ዜተኣከቡ
መረዲታታት ብሜሊ መጠናውን ዒይነታውን ትንተና ተተንቲኖም ቀሪቦም እዮም ፡፡ ውፅኢት ናይዙ
መፅናዕቲ ዴማ ዜተኻተቱ ዒይነታት ስነቃሊት መጠኖም ትሑት፣ብዒይነቶምን ብበዜሖምንይመጣጠኑ
ምኻን፣ንፁር ዕሊማ ይምህሊዎም ፣ግቡእነት ኣቀራርበኦም ትሑት፣ትሕዜቶንምምሃር ዜኣተው
ስነቃሊት ኣብ ስነሌሳን ምኻኑ ተረጋጊፁ እዩ፡፡ ኣብ መወዲእታ ኣብ መፅሓፍ ተምሃራይ ዜኣተው
ስነቃሊት በዜሖምን ዒይነቶምን ተመጣጠንቲ ክኾኑ ይግባእ ። ብፍሊይ ኣብ ምዴሊው መፅሓፍ
ተምሃራይ እትሳተፈ ኣብ ቋንቋ ትግርኛ ስነቃሊት ዕሊመኦም ተነፂሩ፣ክእሇታትንባእታታትን ቋንቋ
መሰረት ገይሩ ንክዲሇው ንዜምሌከቶም ኣካሊት ተሓቢሩ እዩ፡