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Summary: The advanced wireless communication system requires abridged energy consumption, enhanced data rate, and good signal coverage. The massive MIMO technology for 5G systems has been developed to accommodate several users simultaneously with superior throughput. The claim for high data rate wireless communication services is expanding quickly as time goes. Thus, the key difficulty is that as the number of users grows, the number of phase shifters grows as well, causing the system to consume more power; as a result, the system's energy efficiency decreases. Hybrid beamforming has recently emerged as an attractive technique for millimeter‐wave (mmWave) communication systems. The analog beamformer in the RF domain and digital beamformer in the baseband are coupled through a minimal number of RF chains in hybrid beamforming architecture. Hybrid beamforming utilizes fewer RF (radio frequency) chains than the total number of antennas to have a lower energy consumption design. The hybrid beamforming for a mmWave‐based massive MIMO system through different phase shifter selection mechanisms is proposed to achieve the highest energy efficiency for mmWave communications systems. The fully connected with phase shifter selection, sub‐connected with phase shifter selection (SPSS), and fully connected and sub‐connected with phase shifter selection with halved and doubled switches are considered for this research. The simulation results show the SPSS with halved switch outperforms on energy efficiency. [ABSTRACT FROM AUTHOR]

Introduction. The incidence of a pressure ulcer in intensive care units (ICU) is significantly higher than in noncritical care settings. The patients in the ICU are the most vulnerable group to disruption of the skin's integrity. Prior studies in Ethiopia failed to evaluate pressure ulcers in intensive care units and were limited to general wards. The purpose of this study was to identify the incidence and predictors of pressure ulcers in adult patients admitted to intensive care units in Southern Ethiopia. Methods. A single-arm prospective open cohort of 216 patients was used to determine the presence of a pressure ulcer in the intensive care units from June 2021 to April 2022. A consecutive sampling was used until the sample size was reached. The data were collected using a structured questionnaire and analyzed using Stata 14. A cumulative incidence of a pressure ulcer was computed. The life table was used to estimate the cumulative survival. A multivariable Cox proportional hazard regression was used to identify independent predictors of a pressure ulcer. An adjusted hazard ratio with a 95% CI was used to measure the degree of association; a P value ≤ 0.05 was considered significant. Results. Twenty-five patients developed a pressure ulcer (PU), making a cumulative incidence of 11.57%. Out of 25 incident cases of pressure ulcers, four-fifths (80%) of the study patients developed PU within 6 days of their admission to the ICUs. The incidence rate was 32.98 PU per 1000 person-days of ICU stay. Pressure ulcers were most commonly found on the sacrum, followed by the shoulder. Among the incident cases, 52% were stage 2 ulcers. The presence of friction or shearing forces, as well as being 40 years of age or older, was independently associated with pressure ulcers. Conclusion. The overall cumulative incidence of the pressure ulcer was lower than that in other studies but occurred at a faster rate. Age (40 years of age or older) and the presence of friction or shearing forces were the main predictors of pressure ulcers in the intensive care units. Therefore, nurses working in ICUs should continually anticipate the risk of a pressure ulcer. Moreover, special attention should be given to patients of advanced ages. Furthermore, monitoring the installation of a mattress, keeping bed linens unwrinkled, and keeping patients in a proper position on a bed to prevent or reduce friction or shearing forces are very crucial in the prevention of pressure ulcers. [ABSTRACT FROM AUTHOR]

The common bean is the crop used as food, feed, and to improve soil fertility. However, the production and productivity were affected by poor nutrition and fertilizer management, inappropriate interrow spacings, and the poor genetic makeup of the crops in Ethiopia. Hence, a study was conducted in two research stations at Arsi Negele and Melkasa Agricultural Research Center (MARC), during 2019 cropping season. The treatments consisted of three interrow spacings (30 cm, 40 cm, and 50 cm) and three common bean varieties (Dame, SER-119, and KAT-B9) combined in a factorial arrangement laid out in the field using (randomized complete block design) RCBD with three replications. Data on growth and yield parameters obtained were subjected to analysis of variance. Regarding the interaction effect, leaf area, number of seed pods−1, and grain yield were significantly influenced by the interrow spacings and common bean varieties at both locations. Plant height, number of pods plant−1, total dry biomass, leaf area index, hundred seed weight, and harvest index were significantly influenced by the interrow spacings and common bean varieties at Arsi Negele, whereas they were nonsignificant for MARC. In this study, the highest grain yields (2.23 and 2.17 tons/ha) were obtained from narrow interrow spacings (30 and 40 cm) combined with variety SER-119 at both locations. Hence, the highest net benefits (30848.7 and 29970.4 ETB) were obtained from SER-119 (30 cm × 10 cm, and 40 cm × 10 cm) at Arsi Negele and MARC, respectively. It was recommended that the narrow (30 cm) interrow spacing be used with variety SER-119 for common bean production in the study areas and similar agro-ecologies. On the other hand, the use of wider interrow spacings (40 cm or 50 cm) had a significant importance in improving hundred seed weight, seed quality, and disease incidences of common bean varieties at the given studied sites. [ABSTRACT FROM AUTHOR]

We conducted a review of 26 articles published between 2009 and 2021 to determine human-wildlife conflict based on spatial and temporal patterns, biological components, drivers of conflict, and mitigation methods used. We employed search, synthesis, appraisal, and analysis framework for review and VOSviewer software for network analysis. We included articles that only focused on relations between terrestrial wildlife and humans, while others deal with ecology, distribution, and biology of wildlife because it does not go with HWC. Forty-seven species of terrestrial vertebrates were reported in conflict-related studies, being Bovidae and Cercopithecidae the most frequently studied groups, of which eleven are found in threatened list species. The main drivers reported were land use change, proximity to protected areas, and illegal resource exploitation. In the management case, the use of traditional protection techniques such as fencing, guarding, and physical barriers was reported. About 178 keywords' analysis revealed a focus on "coexistence," "mitigation," and "food security." The literature focused mainly on larger mammals, led by Ethiopian authors, and excluded the social dimensions of HWC. Therefore, identifying conflict-prone species focuses on the social dimensions of coexistence, such as human attitudes towards terrestrial wildlife, and broadening the taxonomic and cultural breadth of HWC is required. [ABSTRACT FROM AUTHOR]

Human-wildlife conflict (HWC) is a continuous problem in the world and has a significant impact on both human and wildlife populations. This study was conducted to investigate the HWC around Belo-Bira Forest, Dawro zone, southwestern Ethiopia. We collected data from October 2019 to March 2020 through semistructured questionnaires, focus group discussion, direct observation, and key informant interviews. Our results show that crop damage and livestock predation were common problems caused by Papio anubis, Cercopithecus aethiops, Crocuta crocuta, Canis aureus, and Potamochoerus larvatus. Human population growth, habitat disturbance, proximity to natural forest, and competition between wildlife and livestock are the identified causes of HWC. Moreover, the study identified guarding and fencing as dominant traditional methods used to reduce HWC in our study area. Therefore, local communities can minimize crop loss by using the most effective method in an area, and crops such as wheat, maize, and teff should not be grown near the forest edge. [ABSTRACT FROM AUTHOR]

Tropical cyclones are one of the prominent weather systems that are generated over the tropical oceans. The cyclones that develop in the Southwest Indian Ocean (SWIO) usually travel west then southwest and finally recurve to southeast, generally before reaching the East African coast. However, it is shown in this study how SWIO-tropical cyclones/depressions can indirectly affect Ethiopian weather. Using correlation and composite analyses, interannual and intraseasonal rainfall variations in Ethiopia were compared with the frequency and time of occurrence of the tropical cyclones. Years showing the consecutive occurrence of several tropical depressions over the SWIO coincide with the drought years of Ethiopia. Reciprocally, years of abnormally low frequency of tropical cyclones are associated with heavy rainfall in Ethiopia. Belg rainfall (‘small rains’, February–May) is much more influenced by the cyclonic activity than Kiremt rainfall (‘big rains’, June–September), which occurs outside the cyclonic season of the Southeast Indian Ocean. On a daily basis, rainfall activity during the Belg period is significantly reduced when a tropical depression is observed in the SWIO, before picking up again a few days later. No systematic time-lag was found between the cyclone occurrence and the decrease in daily rainfall amounts. However, at interannual time-scales, a higher (lower) frequency of tropical depressions during the months of November–January tends to be followed by abnormally low (high) Belg rainfall. One of the mechanisms suggested to explain this seasonal persistence in the frequency of tropical depressions involves sea-surface temperatures in the SWIO, from where many of the depressions originate. The atmospheric processes accounting for the teleconnection between Ethiopia rainfall and tropical depressions were examined. Monthly anomalies of upper air winds for years showing frequent occurrence of tropical depressions proved significant not only over the SWIO, but also the Northern Hemisphere above Northeast Africa. In addition to a slightly enhanced cross-equatorial flow, diverting moisture advection towards the active centre of the system, much stronger than usual equatorial easterlies in the upper troposphere and a reduced southward excursion of the subtropical jet stream result in weaker convective activity over Ethiopia. © 1998 Royal Meteorological Society [ABSTRACT FROM AUTHOR]