Central Region Research Articles

Abnormal function of EPHA2/p.R957P mutant in congenital cataract

AIM: To identify genetic defects in a Chinese family with congenital posterior polar cataracts and assess the pathogenicity. METHODS: A four-generation Chinese family affected with autosomal dominant congenital cataract was recruited. Nineteen individuals took part in this study including 5 affected and 14 unaffected individuals. Sanger sequencing targeted hot-spot regions of 27 congenital cataract-causing genes for variant discovery. The pathogenicity of the variant was evaluated by the guidelines of American College of Medical Genetics and InterVar software. Confocal microscopy was applied to detect the subcellular localization of fluorescence-labeled ephrin type-A receptor 2 (EPHA2). Co-immunoprecipitation assay was implemented to estimate the interaction between EphA2 and other lens membrane proteins. The mRNA and protein expression were analyzed by reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting assay, respectively. The cell migration was analyzed by wound healing assay. Zebrafish model was generated by ectopic expression of human EPHA2/p.R957P mutant to demonstrate whether the mutant could cause lens opacity in vivo. RESULTS: A novel missense and pathogenic variant c.2870G>C was identified in the sterile alpha motif (SAM) domain of EPHA2. Functional studies demonstrated the variant’s impact: reduced EPHA2 protein expression, altered subcellular localization, and disrupted interactions with other lens membrane proteins. This mutant notably enhanced human lens epithelial cell migration, and induced a central cloudy region and roughness in zebrafish lenses with ectopic expression of human EPHA2/p.R957P mutant under differential interference contrast (DIC) optics. CONCLUSION: Novel pathogenic c.2870G>C variant of EPHA2 in a Chinese congenital cataract family contributes to disease pathogenesis.

Atherosclerotic cardiovascular disease risk among Ghanaians: A comparison of the risk assessment tools.

ObjectivesRisk stratification is a cornerstone for preventing atherosclerotic cardiovascular disease (ASCVD). Ghana has yet to develop a locally derived and validated ASCVD risk model. A critical first step towards this goal is assessing how the commonly available risk models perform in the Ghanaian population. This study compares the agreement and correlation between four ASCVD risk assessment models commonly used in Ghana. MethodsThe Ghana Heart Study collected data from four regions in Ghana (Ashanti, Greater Accra, Northern, and Central regions) and excluded people with a self-declared history of ASCVD. The 10-year fatal/non-fatal ASCVD risk of participants aged 40–74 was calculated using mobile-based apps for Pooled Cohort Equation (PCE), laboratory-based WHO/ISH CVD risk, laboratory-based Framingham risk (FRS), and Globorisk, categorizing them as low, intermediate, or high risk. The risk categories were compared using the Kappa statistic and Spearman correlation. ResultsA total of 615 participants were included in this analysis (median age 55 [Inter quartile range 46, 64]) years with 365 (59.3 %) females. The WHO/ISH risk score categorized 504 (82.0 %), 58 (9.4 %), and 53 (8.6 %) as low-, intermediate-, and high-risk, respectively. The PCE categorized 345 (56.1 %), 181 (29.4 %), and 89 (14.5 %) as low-, intermediate- and high-risk, respectively. The Globorisk categorized 236 (38.4 %), 273 (44.4 %), and 106 (17.2 %) as low-, intermediate-, and high-risk, respectively. Significant differences in the risk categorization by region of residence and age group were noted. There was substantial agreement between the PCE vs FRS (Kappa = 0.8, 95 % CI 0.7 – 0.8), PCE vs Globorisk (Kappa = 0.6; 95 % CI 0.6 – 0.7), and FRS vs Globorisk (Kappa = 0.6; 95 % CI 0.6 – 0.7). However, there was only fair agreement between the WHO vs Globorisk (Kappa = 0.3; 95 % CI 0.3–0.4) and moderate agreement between the WHO vs PCE and WHO vs FRS. ConclusionThere are significant differences in the ASCVD risk prediction tools in the Ghanaian population, posing a threat to primary prevention. Therefore, there is a need for locally derived and validated tools.

Dengue hemorrhagic fever prediction in coastal area using geographically weighted regression

Dengue hemorrhagic fever (DHF) is still a health problem globally, including in Indonesia. Geographical and climatic conditions in coastal areas are different from other areas, which may impact differences in environmental risk factors for dengue. This study aims to create a prediction model for the incidence of DHF in coastal areas. The research was conducted in Bantul Regency, Indonesia, involving data from 2015-2019. Dengue incidence data were collected from the health office. Climatic data were from climatology station. Data on altitude and shoreline distance were obtained by geographic information system (GIS) processing. Population density and wide settlement area are obtained from the Bureau of Statistics. The geographically weighted regression (GWR) analysis was carried out using GWR4. The results showed that GWR with a weighting of Fixed Bi-Square Kernel obtained an R2 value of 0.7768, better than the global model (R2 0.5254). It indicates that DHF (Y) in Bantul Regency is 77.68% determined by population density (X1), altitude (X2), settlement area (X3), shoreline distance (X4) and rainfall (X5) and the remaining 22.32% are influenced by other variables which are not investigated. Geographically, the predictor variables explain the DHF incidence with a strong category in the central region, and weak in coastal area.

Quantifying the water use efficiency of karst ecosystems and response to environmental factors

Study regionThe study area is located in Guizhou province, the centre of the karst region in southwest China. Study focusAs a typical karst region, Guizhou has long faced challenges with water scarcity. Quantifying water use efficiency (WUE) is crucial for the efficient use of water resources and sustainable management. This study examined the spatio-temporal evolution patterns and its driving factors on WUE in Guizhou using Theil-Sen's slope, partial correlation methods, and the geographic detector model. New hydrological insights for the region(1) The multi-annual mean WUE of non-karst region (NKR, 2.75 gC kg-1 H2O yr-1) is higher than that of karst region (KR, 2.10 gC kg-1 H2O yr-1) during 2001–2020. (2) The rate of increase of WUE was three times higher in KR than in NKR. (3) Precipitation and temperature were identified as the key factors influencing WUE. Interactions between each environmental factors were observed to have both bi-variate and non-linear enhancement effects. Notably, in the NKR, soil moisture, vegetation type and leaf area index were the dominant factors influencing WUE, with interactions between environmental factors had both enhanced and weakened effect on WUE. (4) The synergistic effects of these interactions exceeded the individual or cumulative effects of the two environmental factors. These findings contribute to our understanding of the environmental factors driving changes in WUE in the KR.

Geoscience studies in the Maltese Islands: a gateway to the Central Mediterranean region

Geoscience studies in the Maltese Islands: a gateway to the Central Mediterranean region

A Sociological study of the religious identity of young people in Central Asia and Europe (following the example of Kyrgyz Republic and the Republic of Poland)

The purpose of the article is to determine the situation in the field of religious preferences of young people in the Kyrgyz Republic and the Republic of Poland by studying the specific features and dynamics of the development of traditional beliefs in the Central Asian and European regions. The main methods used in the preparation of the work were the system-analytical method and the statistical method. The characteristic features of different areas of religion in Asia, as well as the origins and root causes of the formation and development of religious trends in Kyrgyzstan, are studied. The key moments in the history of the transformation of the Kyrgyz society in the XVIII-XXI centuries are outlined in the context of the influence of this process on the emergence of specific signs of local religious trends. Different approaches and concepts to the study of the young generation of the Central Asian Republic and Poland are evaluated by considering the qualitative and quantitative results of a number of sociological surveys. The results and conclusions of this work can be used as a basis for the development and implementation of a number of political and social reforms with an emphasis on raising awareness of the issue among the younger generation of Kyrgyzstan.

The influence mechanism of multi-government environmental regulation synergy on corporate environmental responsibility

The United Nations Development Programme (UNDP) calls for enhanced global efforts to achieve the 17 sustainable development goals by 2030, highlighting the crucial role of corporate environmental responsibility (CER) in advancing global sustainability. As a significant participant, China is leveraging its government-led environmental regulation (ER) system, which has a multi-level and multi-sectoral structure, to effectively combat climate change. However, the effect of this ER system, especially collaborative efforts among multiple government subjects, on CER remains unknown. Thus, this paper is the first attempt to investigate the effect and underlying mechanisms of multi-government ER synergy on CER from the perspective of government subject synergy. Using a dataset of Chinese A-share listed manufacturing firms from 2010 to 2021, this study finds the following. First, multi-government ER synergy boosts CER. Direct ER synergy, stemming from joint policy-making across departments, encourages CER in end-of-pipe governance. Indirect ER synergy, arising from administrative hierarchy constraints among multi-level governments, fosters CER in front-end governance. Second, financing constraints and executives’ attention to CER are two key channels through which multi-government ER synergy influences CER. Third, firms with political connections, those in heavily polluting industries, or those located in central and western regions adopt more proactive CER strategies under multi-government ER synergy. This paper expands research on government collaborative governance from the regional macro-perspective to the micro-firm level, providing valuable insights for countries worldwide, particularly emerging economies that share similar characteristics with China, to contain rapidly growing environmental challenges and advance global sustainability.

A ministry to at-risk homeless street youths in the central region of Lusaka, Zambia

The study examined the plight of homeless at-risk street youth who patronize the Lusaka Central Business District. Through observation and interaction, it was revealed that the Seventh-day Adventist Church is not providing an adequate and holistic ministry to the street youth people group. The purpose of this study was to develop, implement, and evaluate a viable intervention and ministry model that seeks to account for both the physical and spiritual needs of street youth. This model is here dubbed the PSR2D model consisting of meeting physical needs, equipping with skills, reform and rehabilitation, and most importantly, discipleship as a way of reaching the street youth. To adequately and meaningfully minister to at-risk street youths, the researcher used the qualitative method to approach the research process. After examining the problem through data derived from focus groups and observations, the researcher designed and implemented a multi-faceted ministry to reach at-risk street youth and thereby create an entering wedge for discipleship. The program started in December 2023 and was completed in March 2024.

Broadband spin and angle co-multiplexed waveguide-based metasurface for six-channel crosstalk-free holographic projection

Metasurface-based holograms, or metaholograms, offer unique advantages including enhanced imaging quality, expanded field of view, compact system size, and broad operational bandwidth. Multi-channel metaholograms, capable of switching between multiple projected images based on the properties of illuminating light such as state of polarization and angle of incidence, have emerged as a promising solution for realizing switchable and dynamic holographic displays. Yet, existing designs typically grapple with challenges such as limited multiplexing channels and unwanted crosstalk, which severely constrain their practical use. Here, we present a new type of waveguide-based multi-channel metaholograms, which support six independent and fully crosstalk-free holographic display channels, simultaneously multiplexed by the spin and angle of guided incident light within the glass waveguide. We employ a k-space translation strategy that allows each of the six distinct target images to be selectively translated from evanescent-wave region to the center of propagation-wave region and projected into free space without crosstalk, when the metahologram is under illumination of a guided light with specific spin and azimuthal angle. In addition, by tailoring the encoded target images, we implement a three-channel polarization-independent metahologram and a two-channel full-color (RGB) metahologram. Moreover, the number of multiplexing channels can be further increased by expanding the k-space’s central-period region or combing the k-space translation strategy with other multiplexing techniques such as orbital angular momentum multiplexing. Our work provides a novel approach towards realization of high-performance and compact holographic optical elements with substantial information capacity, opening avenues for applications in AR/VR displays, image encryption, and information storage.

Transient interactions modulate the affinity of NF-κB transcription factors for DNA

The dimeric nuclear factor kappa B (NF-κB) transcription factors (TFs) regulate gene expression by binding to a variety of κB DNA elements with conserved G:C-rich flanking sequences enclosing a degenerate central region. Toward defining mechanistic principles of affinity regulated by degeneracy, we observed an unusual dependence of the affinity of RelA on the identity of the central base pair, which appears to be noncontacted in the complex crystal structures. The affinity of κB sites with A or T at the central position is ~10-fold higher than with G or C. The crystal structures of neither the complexes nor the free κB DNAs could explain the differences in affinity. Interestingly, differential dynamics of several residues were revealed in molecular dynamics simulation studies, where simulation replicates totaling 148 μs were performed on NF-κB:DNA complexes and free κB DNAs. Notably, Arg187 and Arg124 exhibited selectivity in transient interactions that orchestrated a complex interplay among several DNA-interacting residues in the central region. Binding and simulation studies with mutants supported these observations of transient interactions dictating specificity. In combination with published reports, this work provides insights into the nuanced mechanisms governing the discriminatory binding of NF-κB family TFs to κB DNA elements and sheds light on cancer pathogenesis of cRel, a close homolog of RelA.

Examining the Predictive Capacity of School-based Assessment on Students' Mathematics Performance in Large-scale Examinations

This study underscores the importance of school-based assessment (SBA) in predicting students' mathematics performance in the Basic Education Certificate Examination (BECE) in Ghana. The study was conducted using 150 mathematics teachers from public junior high schools in Ghana's Central Region, the research employed a quantitative approach, using surveys to gather data on internal examination scores, SBA practices, teaching experience, and gender. Regression analysis revealed a strong predictive relationship between internal exam scores and BECE performance (R² = 0.663, B = 0.374, SE = 0.006, t = 67.24, p < .000), while ANOVA showed significant variations in SBA practices based on teaching experience (F (3, 146) = 6.99, p < 0.05). However, t-tests indicated no significant gender differences in SBA practices among teachers (t (148) = 1.100, p = 0.273). These findings highlight the critical role of internal assessments and teaching experience in enhancing educational outcomes and suggest that educational policies should support effective SBA practices and professional development for teachers. Based on these findings, it is recommended to enhance formative assessment practices by focusing on continuous and comprehensive internal assessments, provide ongoing professional development for teachers to improve their skills in implementing SBA, and allocate adequate resources for mathematics education to support effective teaching and learning environments.

The impact of carbon emission trading schemes on China’s economic inequalities between and within urban and rural areas based on the satellite data: a county-level analysis

ABSTRACT Although China’s carbon emission trading schemes (CETS) garnered significant attention in the field of climate mitigation, limited data availability has hindered exploration into the impact of CETS on economic inequality at the county level in China. Given its potential to facilitate industrial upgrading and generate employment opportunities, the adoption of CETS holds promise for reducing economic inequality. To address data limitations, we employed a combination of gridded nighttime light data and land use data to estimate China’s county-level Dagum Gini coefficient and its components. Subsequently, we applied a difference-in-difference-in-difference method to examine how CETS affected economic inequalities between and within urban and rural areas in China. Our findings reveal that: (1) CETS significantly reduced overall economic inequality in counties with a high proportion of secondary industry output; (2) this reduction primarily occurred within urban and rural areas rather than between them. Further heterogeneity analysis demonstrates that while CETS effectively mitigated economic inequality between urban and rural areas in central and western regions, it did not achieve similar outcomes in the eastern region; (3) service industry development and rural GDP per capita served as important channels through which CETS reduced economic inequality within rural areas. Infrastructure development driven by CETS primarily addressed economic inequality within urban areas rather than rural areas.

Individual and community-level factors associated with repeat induced abortion among women in Ghana: a multivariable complex sample logistic regression analysis of 2017 Ghana maternal health survey

BackgroundRepeat induced abortion is a serious public health issue that has been linked to adverse maternal health outcomes. However, knowledge about repeat induced abortion and its associated factors among reproductive age women in Ghana is very scarce. The objective of this study is to examine individual and community factors associated with repeat induced abortion in Ghana which would be helpful to design appropriate programmes and policies targeted at improving the sexual and reproductive health of women.MethodsWe used secondary cross-sectional data from the 2017 Ghana Maternal Health Survey. The study included a weighted sample of 4917 women aged 15–49 years with a history of induced abortion. A multivariable complex sample logistic regression analysis was used to investigate individual and community factors associated with repeat induced abortion among women in Ghana. Adjusted odds ratios (AOR) with 95% confidence intervals (CI) was used to measure the association of variables.ResultsOf the 4917 reproductive women with a history of abortion, 34.7% have repeat induced abortion. We find that, compared to women who experience single induced abortion, women who experience repeat abortion are age 25–34 years (AOR:2.16;95%CI = 1.66–2.79) or 35–49 years (AOR:2.95;95%CI:2.18–3.99), have Middle/JHS education (AOR:1.69;95%CI = 1.25–12.27), use contraceptive at the time of conception (AOR:1.48: 95%CI = 1.03–2.14), had sexual debut before 18 years (AOR:1.57; 95%CI: 1.33–1.85) and reside in urban areas (AOR:1.29;95%CI = 1.07–1.57). On the other hand, women who reside in Central (AOR:0.68;95%CI: 0.49–0.93), Northern (AOR:0.46;95%CI:0.24–0.88), Upper West (AOR:0.24; 95%CI: 0.12–0.50) and Upper East (AOR:0.49; 95%CI = 0.24–0.99) regions were less likely to have repeat induced abortion.ConclusionThe study showed that both individual and community level determinants were significantly associated with repeat induced abortion. Based on the findings, it is recommended to promote sexual and reproductive health education and more emphasis should be given to adult, those with early sexual debut, those with Middle/JHS education and those who live in urban centers.

Efficacy of Treatments in Reducing Inflammatory Lesion Count in Rosacea: A Systematic Review.

Rosacea is a chronic inflammatory skin condition affecting approximately 5.5% of the global population. Patients present heterogeneously with a mix of features in the central facial region, of which papules and pustules are considered to be a major feature. The identification of effective treatments for reducing inflammatory lesions in rosacea can alleviate the psychosocial burden that many rosacea patients experience, including reduced self-esteem, anxiety, and social withdrawal. The objective of this systematic review is to determine the effectiveness of topical and systemic therapies in reducing lesion count in rosacea patients. Medline, Embase, and Cochrane CENTRAL databases were searched, resulting in the inclusion of 43 clinical trials reporting on a total of 18,347 rosacea patients. The most well-studied treatments include ivermectin, metronidazole, azelaic acid, minocycline, and doxycycline. Oral isotretinoin was the most effective treatment in reducing inflammatory lesions and may be recommended for severe recalcitrant cases of rosacea. Several topical and systemic therapies have demonstrated efficacy in reducing inflammatory lesion count in rosacea patients, with mechanisms of action centred around suppressing inflammation and killing Demodex folliculorum mites. Additional research is required to determine effective combination therapies in rosacea.

Phylogenetic diversity of the Pristimantis anaiae species group, with a description of a new species of Pristimantis (Anura, Strabomantidae) from Cerro Candelaria, Tungurahua, Ecuador

Continuous field work on mountains in the upper Pastaza watershed, showed an unexpected cryptic diversity in the recently described Pristimantis anaiae species group. Based on molecular and morphological characters we describe a new frog species from the central region of the eastern Ecuadorian Andes. We present an updated phylogeny for the Pristimantis anaiae species group, based on widely used, ubiquitous, and available genes, three mitochondrial genes (12S rRNA, 16S rRNA, ND1) and RAG1 nuclear gene. Our phylogenetic hypothesis increases genetic diversity of the species group and shows two well-supported subclades. We show the relationships of the new species and include for the first time Pristimantis maryanneae, belonging to a clade related to P. resistencia + P. glendae. Our phylogeny shows that new species, from Cerro Candelaria, is more closely related to P. kunam from Sangay National Park and differs from it by having a less conspicuous dorsolateral row of enlarged tubercles, and sacral oval marks surrounded by thin white pale lines. The new species and two additional undescribed species occur on the south side of the Rio Pastaza Valley, at Cerro Candelaria within the Llanganates – Sangay Ecological Corridor, reflecting the high importance of this area for conservation and understanding of evolution processes in the area, suggesting a probably adaptive radiation zone for the P. anaiae species group.

Measurement and Spatio-Temporal Characteristics of High-Quality Development Efficiency in Metropolitan Areas: A Case Study of the Changchun Metropolitan Area

The concept of high-quality development (HQD) is characterized by its emphasis on efficiency, equity, and environmental sustainability. In the context of China’s new urbanization development, the metropolitan area plays a crucial role in facilitating and sustaining HQD. This study focuses on the Changchun Metropolitan Area (CCMA) as a case study to measure the efficiency of high-quality development (HQDE) at the county level using the super-efficiency SBM model and spatial autocorrelation model. Additionally, we examine the spatio-temporal distribution characteristics of HQDE in terms of economy, innovation, coordination, greenness, openness, and sharing (EICGOS). The main findings are as follows: (1) The HQDE of the CCMA ranges from 0.7 to 0.8 with an initial rapid increase followed by a gradual decline; however, there are notable variations among different counties. (2) Regarding spatial structure within the metropolitan area, highest efficiency is observed in the half-hour living circle followed by the 2-h accessibility circle while lowest efficiency is found in the 1-h commuting circle. Over time, there is a declining trend in efficiency within core leading areas. (3) In terms of dimensions, CCMA demonstrates the highest level of economic development efficiency (EDE), whereas green development efficiency (GDE) exhibits lower levels compared to other dimensions. Furthermore, development efficiencies across all dimensions show a decline over time. (4) Spatially distributed patterns reveal significant agglomeration areas for HQDE within the CCMA region. High-high agglomeration areas are predominantly concentrated in the central region of Changchun and southern region of Liaoyuan while low-low agglomeration areas primarily exist in northwest Songyuan and specific counties within Changchun. To attain HQD of the CCMA, it is advisable to bolster the economic scale of the central city, mitigate developmental disparities between counties and cities, and expedite green transformations in old industrial cities. These findings offer a valuable point of reference for optimizing resource allocation at the metropolitan level and devising strategies to foster regional HQD.

Holocene biome reconstruction on the Chinese loess plateau based on pollen

Reconstruction of past vegetation changes is critical for sustainable development in the fragile and highly eroded ecosystems on the Chinese Loess Plateau (CLP) under global change, particularly in light of future warming events. In this study, we collected fossil pollen data from 40 sites to reconstruct the Holocene (since 11 ka) vegetation pattern of the CLP using the biomization method. The results demonstrate that the CLP vegetation during the entire Holocene was dominated by grassland landscapes in most areas and periods, whereas the forest landscape only developed in some areas during certain periods. Steppe vegetation rather than forest vegetation was distributed in the central region of the CLP. Six forest biomes were primarily distributed in the southwestern and northeastern plateau high-altitude areas, showing notable expansion toward low latitudes and longitudes during the early to mid-Holocene. The steppe biome showed a rather wide distribution, primarily in the center and south, and especially in the expanded western region during the Early Holocene. Minor variations were observed for the widely distributed steppe biomes that shifted to high longitudes and latitudes during the Holocene. The desert biome was identified in the relatively restricted western and northern regions of China. Reconstructed biome spatial distributions showed a large vegetation gradient on the CLP. This suggests that variations in forest biomes on the CLP were potentially influenced by changes in precipitation. Different topographies within the same area led to different biomes. In addition, increased human activity may cause vegetation destruction.

A multi-electrode two-dimensional position sensitive diamond detector

In multi-electrode devices, charge pulses at all the electrodes are induced concurrently by the motion of the excess charge carriers generated by a single ion. This charge-sharing effect is such that the pulse amplitude at each sensitive electrode depends on the device geometry, its overall electrostatic configuration, and the charge transport properties of the detecting material. Therefore, the cross-analysis of the charge pulses induced at each electrode offers implicit information on the position of the ion impact. In this work, we investigate the two-dimensional position sensitivity of a diamond detector fabricated by deep ion beam lithography. By exploiting the ion beam induced charge technique, the device was exposed to a 2 MeV Li+ ion micro-beam to map the spatial dependence of the charge collection efficiency (CCE) on the nominal micro-beam scanning position. The combination of the CCE maps revealed a two-dimensional position sensitivity of the device with micrometric resolution at the center of the active region.

Evaluation of telemedicine medical abortion using a no-test protocol in the Eastern Europe and Central Asian region: Evidence from Ukraine, Uzbekistan, and Azerbaijan.

To evaluate safety, feasibility, and acceptability of a telemedicine medical abortion service without pre-treatment in-person tests in Ukraine, Uzbekistan, and Azerbaijan. We conducted an open-label, prospective, observational clinical study at five clinics in the three countries. Interested and eligible participants scheduled a telemedicine consultation with a study provider by phone or video. Medical abortion pills could be obtained by mail or courier or picked up at the study clinic or a pharmacy. Study providers contacted participants 1 week after mifepristone ingestion to assess abortion outcomes based on symptoms, and 3 weeks later to review the result of an at-home, high-sensitivity, urine pregnancy test. Participants were referred to in-person visit based on symptoms, urine pregnancy test results, or initiative by the participant. In all, 300 women participated in the study. Almost all participants received medical abortion medications the same day as their first contact with the study clinic, and the majority (n = 297, 99.0%) did not experience any problems receiving them. All except two women (0.67%) followed provider instructions on administration of medications. The majority of participants had a complete abortion without a procedure (Ukraine: n = 115, 95.8%; Uzbekistan: n = 127, 97.7%; Azerbaijan: n = 49, 98.0%), few had in-person visits (Ukraine: n = 30, 25.0%; Uzbekistan: n = 3, 2.3%; Azerbaijan: n = 4, 8.0%), and most were very satisfied or satisfied with the service (Ukraine: n = 116, 96%; Uzbekistan: n = 128, 98%; Azerbaijan: n = 45, 90%). No serious adverse events occurred. Telemedicine medical abortion using the no-test protocol is safe, feasible and acceptable for women in Ukraine, Uzbekistan, and Azerbaijan.

Searching for OB-type pre-supernova binary companions inside supernova remnants

Abstract We searched for OB-runaway stars inside supernova remnants (SNRs) as a pre-supernova binary companion. As the majority of massive stars are found in close binary systems, a runaway star ejected by the orbital energy after the supernova (SN) is expected to be found. Considering a binary mass fraction, q=0.25 − 1.0, the runaway star is likely to have an OB spectral type. We selected 12 SNRs at Galactic longitudes 109○ − 189○. Using Gaia astrometry we selected stars having consistent distances with those of the SNRs and showing a peculiar proper motion directed away from the central region of the SNRs. We also determined the radial distribution of the extinction towards the SNRs and estimated the spectral types of the OB-runaway candidates through Gaia and 2MASS photometry. We found two candidates among 12 SNRs. By spectroscopic observations, Gaia DR3 195632152560621440 inside SNR G166.0+4.3 was found to be an evolved A3 type star which cannot be the pre-SN binary companion to the progenitor. Gaia DR3 513927750767375872 inside SNR HB 3 is the only OB-runaway candidate (2-D space velocity of 33.3±3.3 km s−1). Based on photometric study, the star can be an early B-type main sequence star with a slightly higher extinction relative to the SNR, however, it might instead be an evolved A-type star at the same distance. The other 11 SNRs do not host an OB-runaway star within their central regions. Although the runaway search was performed in a large interval of distance and extinction, we also estimated distances to the SNRs.