Search Results (80)

Autism spectrum disorder (ASD) encompasses a range of neurodevelopmental conditions characterized by impairments in social abilities and communication. Studying appropriate animal models can enhance our understanding of the neural mechanisms underlying these conditions, potentially leading to improved treatment and intervention strategies. Modeling impairments in linguistic development and vocal communication caused by autism had been a challenging goal for a long time. Prenatal valproic acid (VPA) treatment has been successfully used to induce ASD-like behavioral symptoms in several vertebrate species including birds. Applying VPA-treatment on songbirds, therefore, offers a promising research paradigm to model ASD. In this study, we investigated the effect of embryonic VPA treatment on song learning in the highly social zebra finch (Taeniopygia guttata). Fertilized eggs were injected with either 0.45 µmol VPA or a saline solution on day 9 of incubation, and hatchlings were allowed to stay with their parents until day 35 post-hatching to facilitate song learning from the father. Once male offsprings reached adulthood, their songs were recorded and compared to those of their fathers. VPA-exposed males exhibited significantly greater similarity to their fathers’ songs compared to control males (74% vs. 31%, respectively), suggesting a reduced ability to modify and develop their own vocal patterns as subadults. Additionally, they showed higher entropy in their songs compared to controls (−1.4 vs. −1.7), indicating more disorganized vocalizations. These findings suggest that prenatal VPA exposure disrupts typical song learning and vocal development in zebra finches, likely by affecting neural mechanisms involved in vocal learning and crystallization of the songs. Our study suggests VPA treatment in songbirds provides a useful tool to model and investigate linguistic developmental disorders related to ASD in humans. Full article

There is a debate on the role of education as a tool to challenge or enforce authoritarian attitudes. Many posit that education, particularly higher education, reduces authoritarianism; whereas vast research indicates that education can be used as an authoritarian tool for regime survival. This suggests that there are other intervening factors, such as the curriculum used, the teaching methodology implemented, and the educational administration employed, to securitise the academic space and impose authoritarian attitudes. Informed by the notion of hegemony and the banking concept of education, this article explores the nexus between education and authoritarianism, determining the role of education as an authoritarian tool for regime survival. We use the case of Eritrea, a country that has been under authoritarian government for more than two decades. The article is based on a literature review because it is risky to conduct an objective empirical study on the “politics of education” in Eritrea, given the country’s political sensitivity. The findings suggest that the Eritrean government politicises the curriculum and militarises secondary and higher education levels to create false consciousness and maintain power. The article contributes to advancing knowledge regarding the nexus of authoritarianism and education, helping people understand the state of the politics of education. Full article

Soil erosion is a significant environmental issue that threatens the stability of land and agricultural productivity. In Eritrea, erosion remains understudied, limiting effective land management. This study assesses soil erosion and maps erosion risk in the Mai Nefhi watershed using the Revised Universal Soil Loss Equation (RUSLE), integrated with Geographic Information System (GIS) and remote sensing (RS) data. Key parameters were analyzed, including rainfall erosivity (R), soil erodibility (K), slope length and steepness (LS), cover management (C), and conservation practice (P). A severity classification identified five risk levels: low (0–7), moderate (7–22), high (22–45), very high (45–90), and severe (90–250) t ha⁻¹ yr⁻¹ with an area coverage of 61.93%, 22.05%, 5.62%, 6.43%, and 3.94%, respectively. Among all the parameters, the LS factor was identified as the dominant driver of soil loss, with erosion rates increasing sharply on slopes above 30%. There was a weak inverse relationship between soil organic matter and erosion (R² = 0.279), indicating that only 27.9% of the variability in soil erosion rates can be explained by SOM content alone. This result further suggests other dominant factors like slope and land use. The findings underscore the need for slope-sensitive conservation strategies, including terracing, agroforestry, and restrictions on hillside cultivation. Full article

Slide burnishing is a non-material-removal process that improves surface finish by plastically deforming peaks into valleys using a spherical hard tool. Conventionally, multiple passes were applied with the same setup to address residual peaks, even though the first pass achieves most of the deformation. Each pass consumes equal time and energy unless parameters like feed or force are adjusted, and changing these parameters requires another cycle of passes. This repetitive approach leads to inefficiencies in time and energy, highlighting the need for different approaches to reduce redundancy while improving surface integrity. This experiment aims to change these processes by changing the feed after each pass to help the tool follow a different path than the first round. Four levels of tool feed with three levels of force and three passes were tested in nine runs that required 27 runs in the conventional method for comparison and were used to burnish the face-milled C45 steel. The new method enhanced the initial surface with up to a 66.6% decrease in Sq, greater than by the old method, and up to 69.3% in Ssk. The new method showed more steady and predictable changes of skewness than the old method during parameter changes. The old method performed better in reducing kurtosis levels when a higher number of passes (three and four) were used. These results demonstrate significant improvement over the traditional techniques, paving the way for innovative advancements and further research in the field. Full article

Refugees have different disease patterns than the population in receiving countries. Furthermore, refugees face barriers to accessing health care services and treatment. The purpose of this study was to describe the prevalence of eosinophilia and elevated IgE levels in refugees and assess the clinical follow-up. Using a cross-sectional study design, we offered health assessments, including eosinophil count and IgE level measurements, to all newly arrived refugees in a Danish municipality from January 2016 to November 2018. In a subgroup, we assessed the clinical follow-up. The study population consisted of 793 refugees, all of whom had eosinophil counts measured, with 411 also having IgE levels measured. Notably, 48.6% were female and most participants originated from Syria, Eritrea, Iran or Afghanistan, with smaller representation from several other countries. Notably, 6.8% had eosinophilia and 32.1% had elevated IgE levels. Syrian origin was associated with a lower prevalence of both biomarkers, and Eritrean origin with a higher prevalence. In a subgroup of 116 participants with abnormal results, general practitioners brought attention to the elevated levels in 50.9% of the cases, and 31.0% of these received a diagnosis related to the findings. In total, 98.3% (114) of patients in the subgroup had contact with their GP following the health assessment. In refugees, eosinophilia and elevated IgE levels are common conditions, and underlying causes are often not diagnosed, potentially leading to inadequate treatment and worse health outcomes. Full article

Bengala, a steamer that sank in 1889 near Capo Rizzuto, Italy, was a relatively new vessel for its time, with an unusually short 18-year service life, given that steamers of the period typically operated for 30 to 40 years. Despite its brief history, SS Bengala played a significant role in the development of Italy’s young merchant navy, undergoing multiple ownership changes and serving various Italian shipping companies. Employed mainly along the route to Southeast Asia, it transported Italian migrants overseas and also participated in troop raids during the Italian military expedition to Eritrea in 1887. Despite its historical significance, no iconographic material has yet been found to depict SS Bengala, and archival research conducted in Italy and England has not uncovered any naval plans, photographs, or drawings of the ship. To overcome this gap, the authors employed new technologies and historical information to create a virtual reconstruction. This research combined archival sources with underwater surveys, including a detailed 3D survey by divers and archaeologists. Archival research, including consultation of official documents, provided critical information on the ship’s dimensions, superstructure, rigging, materials, and construction methods. The 3D modelling of the ship’s external hull, based on precise geometric data from the wreck site, offers a first step towards virtual reconstruction. The modelling is grounded in photogrammetric surveying techniques, ensuring high accuracy in the reconstruction process. The model can be used in augmented reality (AR) applications to enhance underwater exploration, allowing divers to visualise the reconstructed ship in its original environment. Additionally, it supports museum exhibits, interactive visualisations, and educational games, making it a valuable resource for engaging the public with maritime history and archaeology. Full article

Systematic studies on Late Islamic cemeteries that integrate architectural, ritual, and biological aspects remain relatively rare, particularly in Islamic countries or regions with an active Muslim presence. Typically, available research focuses more on epigraphic and artistic features. Since 2018, excavations at the Cathedral and surveys in the ruins of the city of Adulis (Massawa, Eritrea) have uncovered 326 Muslim graves: six dating to the 15th and 18th centuries CE and 320 attributed to the mid-19th to the early 20th century CE. These discoveries have enabled, for the first time in Eritrea, a detailed scientific study of the biological characteristics of the human remains, the funerary architecture, and the burial rites of Muslim communities from the 15th to the early 20th century. The skeletal remains were analyzed through taphonomic and anthropological studies. The graves were categorized into various typologies based on their structural features, while evidence of funerary rituals was documented as indicative elements of the burial practices adopted. These findings were further enriched by ethnographic sources and collaborative work with local communities, who acted as custodians of the historical memory and traditions of the region. The results provide insights into a historical period of Eritrea that is otherwise poorly documented. More broadly, they contribute to the understanding of the history of the Horn of Africa, a region with limited data from funerary and archaeological contexts. The Muslim cemeteries of Adulis represent the most extensively investigated Muslim burial site in recent years, providing critical insights into the historical Muslim presence in the region. These findings also allow researchers to hypothesize the succession of various communities that chose Adulis as a central location for interring their deceased, reflecting its enduring significance as a focal point for cultural and ritual practices across different periods. Full article

Over 30 million people rely on Lake Victoria for survival in Northeast African countries, including Ethiopia, Eritrea, Somalia, and Djibout. The lake faces significant challenges due to changes in land use and climate. This study used multi-source remote sensing data in the Google Earth Engine (GEE) platform to create Land Use and Land Cover (LULC), land surface temperature (LST), and Normalized Difference Water Index (NDWI) layers in the period 2000–2023 to understand the impact of LULC and climate change on Lake Victoria Basin. The land use/land cover trends before 2020 indicated an increase in the urban areas from 0.13% in 2000 to 0.16% in 2020. Croplands increased from 6.51% in 2000 to 7.88% in 2020. The water surface area averaged 61,559 square km, which has increased since 2000 with an average rate of 1.3%. The “Permanent Wetland” size change from 2000 to 2020 varied from 1.70% to 1.83%. Cropland/Natural Vegetation Mosaics rose from 12.77% to 15.01%, through 2000 to 2020. However, more than 29,000 residents were displaced in mid-2020 as the water increased by 1.21 m from the fall of 2019 to the middle of 2020. Furthermore, land-surface temperature averaged 23.98 degrees in 2000 and 23.49 in 2024. Full article

This paper presents an experimentally based study aimed at assessing the viability of employing a commercial energy harvester to develop a self-powered end-stroke and speed sensor for pneumatic cylinders. An energy-harvesting device was integrated into a cylinder end-cap to recover energy from the piston impact at the end of the stroke. The recovered energy powers a radio transmitter that communicates the reach of the end-stroke. This avoids the use of a dedicated end-stroke sensor, reducing the number of components in the system and also saving energy. The experiments aimed to analyze the signal characteristics generated by the module at various activation speeds, assessing whether the impact speed could be distinguished from the signal. Energy output and short-term usage effects were also investigated. The study seeks to further develop and adapt a Simulink model of the system, based on recent studies, and validate it with experimental findings at the tested activation speeds. Following confirmation of the adapted model’s validity, the authors propose using genetic algorithms to design an optimized mechanical energy harvester. This approach aims to find the parameters of an energy harvester more suitable for pneumatic cylinder applications that would enable enhanced energy extraction and overall improved performances. Full article

The current study was carried out to characterize chalky soil bacteria obtained from the rhizosphere of Acacia species growing in Abardae, Maekel Region of Eritrea. This study collected three chalky soil samples from the rhizosphere of Acacia ethibica, Acacia origena, and non-rhizospheric soil. The samples contained 1.42 × 10¹⁰, 5.35 × 10⁹, and 5.68 × 10⁷ cfu/g of culturable bacteria, respectively. A total of 80 bacterial strains were isolated, with ten selected for further study based on their distinct morphology. The researchers examined the cell morphology and the antimicrobial and plant growth-promoting activity of the chosen bacterial isolates. The study’s findings identified that the aerial mycelium of the strain EAE-1 displayed a unique and previously unreported arrangement of hyphae-bearing spores. The antimicrobial test results also showed that bacterial strains EAE-1, EAE-3, EAE-14, EAE-15, EAE-40, and EAO-24 displayed a wide range of antimicrobial activity against the examined phytopathogens. Furthermore, the seed germination result showed that the majority of bacterial strains had a positive effect on wheat growth, with strains EAE-40 and EAO-17 particularly enhancing maize growth. To sum up, the substantial capabilities of these strains position them as promising candidates for biotechnological applications. This study also represents the preliminary analysis of the microbial composition of Eritrean soil. Full article

Additive manufacturing (AM)’s ability to produce customized products with reduced material wastage and other advantages helped the technology to gain popularity in many industries. However, its poor surface integrity is its weak side, and to overcome this, additional post-processes are essential. Slide diamond burnishing, known for its enhancement of surface roughness, residual stress, microhardness, and other properties, was combined with grinding in this research after 3D printing of MetcoAdd 17-4PH-A to mitigate the mentioned shortcomings. This study aimed to analyze the effects of each process on surface roughness, residual stress (both on the surface and in-depth), and microhardness. Workpieces were ground with the same parameters and burnished with four levels of force, feed, and number of passes. The L16 Taguchi experimental design was used to optimize the process parameters and to study their effects. For surface roughness, the optimum parameters were found to be 60 N force, 0.02 m/min feed rate, and three passes. The longitudinal surface residual stress has optimal values at 80 N force, 0.02 m/min feed rate, and four passes. In the case of transverse surface residual stress, the optimal values were 60 N force, 0.17 m/min feed rate, and three passes. Microhardness was maximized with 60 N force, 0.02 m/min feed rate, and one pass. Additionally, the in-depth residual stress for selected surfaces was investigated, and 100 N force showed a deep burnishing effect. Further multi-objective optimization using desirability function analysis found that the optimal parameters for all responses were achieved at the fourth burnishing force level (100 N), the first tool feed level (0.02 m/min), and the fourth number of passes level (four passes). Ultimately, both grinding and burnishing processes exhibited significant enhancements in the measured parameters. Full article

We developed and applied a new calibration method to make more accurate measurements with our multi-color ellipsometric mapping tool made from cheap parts. Ellipsometry is an optical technique that measures the relative change in the polarization state of the measurement beam induced by reflection from or transmission through a sample. During conventional ellipsometric measurement, the data collection is relatively slow and measures one spot at a time, so mapping needs a long time compared with our new optical mapping equipment made by an ordinary color LED monitor and a polarization-sensitive camera. The angle of incidence and the incident polarization state is varied point by point, so a special optical calibration method is needed. Three SiO₂ samples with different thicknesses were used for the point-by-point determination of the angle of incidence and rho (ρ) corrections. After the calibration, another SiO₂ sample was measured and analyzed using the calibrated corrections; further, this sample was independently measured using a conventional spectroscopic ellipsometer. The difference between the two measured thickness maps is less than 1 nm. Our optical mapping tool made from cheap parts is faster and covers wider area samples relative to conventional ellipsometers, and these correction enhancements further demonstrate its performance. Full article

The Deki Amhare complex is located in central Eritrea, within the Arabian–Nubian Shield (ANS). It consists of an inner core of monzogranite porphyry and diorite enclaves (MMEs), surrounded outwardly by granodiorite and quartz diorite. The zircon U–Pb ages, whole-rock geochemistry, and Sr–Nd–Hf isotopic compositions of the Deki Amhare complex granitoids were used to discuss the Neoproterozoic tectonics of the ANS. The Late Tonian granodiorite and quartz diorite are metaluminous and calc-alkaline to slightly high-K calc-alkaline I-type plutons, with ages of 811.2 ± 4.8 Ma and 811.6 ± 5.7 Ma, respectively. They exhibit positive ε_Hf(t) (7.6–9.5) and ε_Nd(t) (3.9–4.7) values and relatively low (⁸⁷Sr/⁸⁶Sr)_i ratios (0.70374–0.70463), indicating that they derived from the partial melting of a metasomatized mantle wedge during intra-oceanic subduction. The Ediacaran monzogranite porphyry and MMEs are subalkaline to alkaline A₂-type granitoids with ages of 620.0 ± 4.3 Ma and 614.8 ± 3.9 Ma. These display positive ε_Hf(t) (5.3–8.7) and ε_Nd(t) (4.2–4.7) values, as well as low (⁸⁷Sr/⁸⁶Sr)_i ratios (0.70310–0.70480), implying that they formed through crust–mantle magma mixing related to post-collisional slab break-off. Based on these data, three stages of regional tectonic evolution can be described: (1) from ~1200 Ma to ~875 Ma, the mafic oceanic crust was derived from depleted mantle during the opening of the Mozambique Ocean; (2) from ~875 Ma to ~630 Ma, intra-oceanic subduction and arc formation occurred with the development of I-type batholiths; and (3) from ~630 Ma to ~600 Ma, crustal and lithospheric reworking took place post-collision, leading to the formation of A₂-type granitoids. Full article

Prior research has highlighted important healthcare access and utilization issues among new forced immigrants. We aimed to explore the role that public and patient involvement (PPI) might play in enhancing accessibility and specific contributions to migration health studies. We conducted open and in-depth interactive virtual discussions with asylum seekers and refugees from Eritrea and Syria in Switzerland. The PPI establishment consisted of three phases: inception, training and contribution. Prior to training, the concept of PPI was not straightforward to grasp, as it was a new approach—however, after training and consecutive discussions, participants were ardent to engage actively. We conclude that PPI holds promise in regard to raising awareness, improving healthcare system accessibilities and utilization, and enhancing and strengthening migration health research. Indeed, PPI volunteers were keen to raise their community’s awareness through their networks and bridge an important gap between researchers and the public. Full article

To reveal genetic diversity for effective resistance to five foliar diseases and toxic aluminum ions, the entire collection of wheat species from the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR) originating from Ethiopia and Eritrea were studied regarding their traits. The collection contains 509 samples of four wheat species (Triticum aestivum—122 samples; T. aethiopicum—340 samples; T. polonicum—6 samples; and T. dicoccum—41 samples). The majority of accessions are new entries of landraces added to the Vavilov collection as a result of the Russian–Ethiopian expedition in 2012. Wheat seedlings were inoculated with causal agents of leaf rust (Pt), powdery mildew (Bgt), Septoria nodorum blotch (SNB), and dark-brown leaf spot blotch (HLB). The types of reaction and disease development were assessed to describe the levels of resistance. All samples of T. aethiopicum were also screened for seedling and adult resistance to Pt, Bgt, and yellow rust (Pst) under field conditions after double inoculation with the corresponding pathogens. To study tolerance to abiotic stress, seedlings were grown in a solution of Al³⁺ (185 µM, pH 4,0) and in water. The index of root length was used to characterize tolerance. Seedlings belonging to only two accessions out of those studied—k-68236 of T. aethiopicum and k-67397 of T. dicoccum—were resistant to Pt at 20 °C but susceptible at 25 °C. Specific molecular markers closely linked to the five genes for Pt resistance effective against populations of the pathogen from the northwestern region of Russia were not amplified in these two entries after PCR with corresponding primers. Four entries of T. dicoccum—k-18971, k-18975, k-19577, and k-67398—were highly resistant to Bgt. All samples under study were susceptible to HLB and SNB. Under field conditions, 15% of the T. aethiopicum samples were resistant to Pst, both at the seedling and the flag leaf stages, but all were susceptible to the other diseases under study. Among the evaluated samples, 20 entries of T. aestivum, 1 of T. polonicum (k-43765), and 2 of T. dicoccum (k-18971, k-67397) were tolerant to aluminum ions. The identified entries could be valuable sources for the breeding of T. aestivum and other wheats for resistance to biotic and abiotic stresses. Full article