Ho Chi Minh City Open University Journal of Science
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Radiation shielding and physical properties of ZrO2-modified borosilicate glasses: A Monte Carlo, theoretical, and AI-based study
No full textThis study investigates the radiation-shielding and physical properties of zirconium dioxide-modified borosilicate glasses using combined Monte Carlo particle transport simulations, theoretical calculations, and Artificial Intelligence-based approach. A Na2O–BaO–TiO2–Al2O3–SiO2–B2O3 glass series containing 0−12 mol% ZrO2 was systematically evaluated for photon and charged-particle interactions, as well as its thermophysical and optical properties. The results show that ZrO2 acts as an effective compositional modifier that increases glass density and network compactness, leading to improved macroscopic gamma shielding indicators, as reflected by reduced mean free path, half-value layer, and tenth-value layer values across the 0.2−4 MeV energy range. Notably, Zeff and Neff exhibit a decreasing trend with increasing ZrO2 content, indicating that the observed attenuation gains are primarily density-driven rather than governed by increases in effective atomic descriptors. A strong correlation between GEANT4 Application for Tomographic Emission Monte Carlo results and XCOM data confirms the reliability of the simulation methodology. For charged particles, the stopping power increases at low energies and decreases beyond the peak for protons and alpha particles, while electrons show a decrease up to ∼1 MeV followed by a sharp rise at higher energies, mainly because bremsstrahlung related energy losses become dominant. In parallel, SciGlass Next predictions for viscosity, glass transition temperature, and refractive index indicate that Zr4+ strengthens the glass network and enhances optical density. Overall, controlled ZrO2 incorporation enables concurrent optimization of shielding efficiency and thermophysical/optical performance, highlighting these lead-free glasses as promising candidates for radiation-shielding observation windows and related applications in nuclear technology and medical fields
Khả năng chấp nhận công nghệ số và năng lực cạnh tranh của các nhà cung cấp dịch vụ logistics Việt Nam trong bối cảnh chuyển đổi số
No full textIn the context of digital transformation in the logistics industry, improving the competitiveness of Logistics Service Providers (LSPs) in Vietnam has become extremely necessary. This article aims to explore the factors affecting competitiveness based on Dynamic Capabilities Theory (DCT) and Value Chain Theory (VCT), and the TOE (Technology-Organization-Environment) theoretical framework. Data were collected from semi-structured interviews with eight LSP experts operating domestically and internationally. Qualitative analysis with NVivo shows that TOE categorizes digital adoption technology (ADT), while Agile Management (AM), Autonomy (AU), and Value Creation Services (VCS) act as dynamic capabilities that enhance the competitiveness (COM) of LSPs. From these results, important recommendations for LSPs are to combine digital technology investment with flexible governance, autonomy, and development of value-creating services, in order to enhance competitiveness in global integration.Trong bối cảnh chuyển đổi số đang diễn ra trong ngành logistics, việc cải thiện năng lực cạnh tranh của nhà cung cấp dịch vụ logistics (LSP) tại Việt Nam trở nên hết sức cần thiết. Bài viết nhằm khám phá các yếu tố tác động đến năng lực cạnh tranh trong bối cảnh số hóa, dựa trên Thuyết Năng lực động (DCT) và Thuyết Chuỗi giá trị (VCT) và khung lý thuyết TOE (Công nghệ, Tổ chức, Môi trường). Dữ liệu được thu thập từ bài phỏng vấn bán cấu trúc với tám chuyên gia đến từ LSPs có hoạt động trong và ngoài nước. Kết quả phân tích định tính bằng phần mềm NVivo cho thấy việc vận dụng TOE như khung phân loại để cấu trúc yếu tố khả năng chấp nhận công nghệ số (ADT) trong khi quản trị linh hoạt (AM), tự chủ (AU) và dịch vụ tạo giá trị (VCS) đóng vai trò như các năng lực động, bổ trợ lẫn nhau và tác động đến năng lực cạnh tranh (COM) của LSPs. Từ kết quả này, khuyến nghị cho các LSP cần kết hợp đầu tư công nghệ số với quản trị linh hoạt, trao quyền tự chủ và phát triển dịch vụ tạo giá trị, nhằm nâng cao năng lực cạnh tranh trong hội nhập toàn cầu
Amaranthus Palmeri S. Wats.'In Soya (Glycıne Max L.) İle Rekabeti Ve Allelopatik Etkilerinin Araştırılması
No full textExpression patterns of apoptosis- and ferroptosis-associated transcripts in uterine tissues of female dogs diagnosed with open- or closed-cervix pyometra
No full textIn dogs diagnosed with pyometra, cervical patency status may influence the predominance of apoptosis or ferroptosis, two mechanistically distinct forms of regulated cell death. We evaluated the expression of selected transcripts related to apoptotic and ferroptotic pathways in the uterine tissuee of female dogs diagnosed with open- or closed-cervix pyometra. Twenty-four bitches were classified as healthy (n = 8), open-cervix pyometra (n = 8), or closed-cervix pyometra (n = 8). Uterine tissue samples from each dog were collected for the quantification of apoptotic- (BAX, BCL-2, TP53, and CASP3) and ferroptosis-related transcripts (GPX4, SLC7A11, and TFRC) via qPCR. Immunohistochemical analysis was conducted using antibodies specific to the proteins encoded by BAX, BCL2, TP53, CASP3, GPX4, SLC7A11, and TFRC genes. Furthermore, protein-protein interaction (PPI) and enrichment analyses for the same genes were conducted. Data were fitted in Kruskal-Wallis tests to fit the effect of healthy, open-cervix pyometra, or closed-cervix pyometra on gene expression profile and immunohistochemistry staining parameters. Compared to control, the expression of BAX, SLC7A11, TFRC, GPX were upregulated, BCL2 was downregulated in closed-cervix pyometra. Mild and strong immunopositivity in BAX, BCL2, TP53, CASP3 antibodies was observed in closed pyometra cases. In closed-cervix pyometra, severe inflammation was observed in the endometrium, with immunopositivity for SLC7A11 and GPX4 highlighted within the cytoplasm of mononuclear inflammatory cells, primarily located in the endometrial stroma. PPI analysis revealed proteins encoded by target genes, such as FADD, FASLG, and GSDME, considering maximum of 20 interactions per protein, resulting network highlights significant roles of proteins in various biological pathways, including apoptosis, ferroptosis, inflammation, cellular immunity. Apoptosis and ferroptosis are regulated in pyometra related cervical patency status and these pathways, more active in closed-cervix pyometra. This is the first study to identify apoptosis and ferroptosis pathways in pyometra, providing new insights into its pathophysiology and emphasizing prognostic relevance of both pathways, particularly in closed-cervix cases
Determination of Pregnancy Stress, Prenatal Attachment, and Traumatic Childbirth Perceptions of Pregnant Women Affected by the Earthquake
No full textHIV and Pregnancy in Türkiye: Gaps and Gains in the Era of Modern ART: A Multicenter Cohort Study
No full textWe aimed to review perinatal outcomes in HIV-positive pregnant women and their infants, as well as Turkish clinicians’ approaches to the management of HIV in pregnancy. This multicenter cohort study included pregnant women living with HIV (WLWH) across Türkiye from 2010 to 2024. 209 pregnancies among 162 WLWH were identified. Nearly 90.9% were diagnosed before or during pregnancy, and 90% were on antiretroviral therapy (ART) at delivery. 150 women had viral loads of less than 1,000 copies/mL during labor. The most chosen ART combination during pregnancy was tenofovir/emtricitabine+raltegravir. Most common mode of delivery was cesarean section (78.9%). Among 174 deliveries, 22 (12.6%) were preterm. Regarding newborn prophylaxis, 137 (88.4%) received zidovudine and 34 received nevirapine. 14 infants were breastfed. No congenital malformation, neonatal or maternal mortality was observed. Overall, 13 infants were diagnosed HIV-positive, indicating an MTCT rate of 7.9% in this cohort. Breastfeeding (OR: 30.1, 95% CI: 4.70-193.50, p <.001) and absence of ART during pregnancy (OR: 30.9, 95% CI: 5.20-183.90, p <.001) were the most prominent variables affecting the infants’ HIV positivity. Despite efficient preventative strategies announced over years, we report a high MTCT rate of 7.9%, aligning with previous literature from Türkiye. The findings highlight that the absence of ART and breastfeeding remain critical risk factors for perinatal HIV transmission. This large real-world cohort, reflecting Turkish clinicians’ practices, helps define major gaps in MTCT prevention in the modern ART era and provides valuable evidence to inform clinicians, policy makers, and public health strategies
Evaluation of novel rapid colorimetric colistin resistance detection methods: Rapid Colistin Disc Elution Test in Klebsiella pneumoniae and Rapid Resazurin Disc Elution Test in Acinetobacter baumannii strains.
No full textStafilokoklarda Dezenfektan/Antiseptik Direnç Genleri ve Klinik Stafilococcus aureus izolatlarının serotiplendirmesi
No full textIntroduction: Staphylococci are commonly isolated from healthcare settings worldwide. Methicillin-resistant Staphylococcus aureus (MRSA) is among the most important causes of nosocomial infections. Objectives: This study aims to evaluate the resistance of Staphylococci to the most commonly used disinfectants and antiseptics in healthcare settings and the detection of the dominant serotype of Staphylococcus aureus in Hatay province.Methodology: The frequency of disinfectant/antiseptic resistance genes was detected by the polymerase chain reaction (PCR) technique in identified staphylococcal strains, and antibiotic susceptibility of strains was evaluated phenotypically. Staphylococcus aureus strains were classified in terms of clonal and phylogenetic relationships with Pulse Field Electrophoresis and spa sequence typing methods.Results: The identification rate of coagulase-negative staphylococci was 43.2% and the others (56.8%) were Staphylococcus aureus. Among these isolates, 103 methicillin-resistant S. aureus were identified. It was determined that 81 (78.64%) of these isolates harbored qacA/B and/or smr genes. The dominant spa serotype was found to be t223.Conclusions: According to spa serotyping results, it was detected the serotype t223 was the dominant clone in our region, unlike the t030 was dominant in Turkey. Since there are many Syrian immigrants living in the Hatay region due to its geographical location, being the dominant clone of a different serotype has an epidemiologically significant importance</p
TÜRKOĞLU (KAHRAMANMARAŞ) İLÇESİ ARAZİ KULLANIMI ZAMANSAL DEĞİŞİMİNİN (1987-2024) COĞRAFİ BİLGİ SİSTEMLERİ (CBS) ve UZAKTAN ALGILAMA (UA) YÖNTEMLERİYLE İNCELENMESİ
No full textBu çalışma, Kahramanmaraş’ın Türkoğlu ilçesinde 1987–2024 yılları arasında meydana gelen arazi kullanımı ve arazi örtüsü değişimlerini inceleyerek bölgenin zamansal dinamiklerini ortaya koymayı amaçlamaktadır. Hızla değişen çevresel koşullar ve insan faaliyetlerinin bölge üzerindeki etkilerini anlamak, sürdürülebilir bir gelecek planlaması için kritik önem taşımaktadır. Araştırma, bölgedeki fiziksel değişimin boyutlarını bilimsel bir yaklaşımla analiz ederek, doğal kaynakların korunması ve arazi yönetimi politikalarına temel oluşturacak kapsamlı bir veri tabanı sunmaktadır.Araştırmada veri kaynağı olarak, 1987-2024 dönemini kapsayan Landsat 5 TM ve Landsat 8 OLI/TIRS uydu görüntüleri kullanılmıştır. Uzaktan Algılama (UA) ve Coğrafi Bilgi Sistemleri (CBS) teknikleri temelinde yürütülen çalışmada, görüntüler öncelikle sayısal görüntü işleme aşamalarından geçirilmiştir. Çalışma alanı; tarım alanı, çayır/mera–sürülmemiş arazi, çıplak/ham toprak, orman, sulak alan ve yerleşim alanı olmak üzere altı temel sınıfa ayrılmıştır. Bu sınıfların belirlenmesinde ve haritalandırılmasında kontrollü (supervised) sınıflandırma yöntemi tercih edilmiştir.Elde edilen bulgular, 1987 yılından 2024 yılına kadar geçen süreçte Türkoğlu ilçesinde arazi deseninin dramatik bir şekilde dönüştüğünü göstermektedir. Dönemsel karşılaştırmalar sonucunda (1987–1997, 1997–2007, 2007–2017 ve 2017–2024), tarım alanları, ormanlar ve sulak alanlarda belirgin bir azalma kaydedilirken; yerleşim alanlarında hızlı bir artış ve çıplak/ham toprak alanlarında genişleme saptanmıştır. Bu değişimlerin temel nedenleri olarak nüfus artışı, kentsel yayılma, tarımsal faaliyetlerdeki dönüşüm, ekonomik farklılaşma ve iklimsel değişkenlikler ön plana çıkmaktadır. Çalışma sonucunda üretilen tematik haritalar ve istatistiksel veriler, bölgenin sürdürülebilir arazi yönetimi ve çevresel planlama süreçleri için stratejik bir rehber niteliği taşımaktadırThis study aims to examine the land use and land cover (LULC) changes that occurred in the Türkoğlu district of Kahramanmaraş between 1987 and 2024, revealing the temporal dynamics of the region. Understanding the impacts of rapidly changing environmental conditions and human activities is of critical importance for sustainable future planning. The research provides a comprehensive database for the development of sustainable land management, environmental planning, and natural resource protection policies by analyzing the dimensions of physical change in the region through a scientific approach.Landsat 5 TM and Landsat 8 OLI/TIRS satellite images covering the 1987–2024 period were utilized as primary data sources. In the study, conducted using Remote Sensing (RS) and Geographic Information Systems (GIS) techniques, the images underwent digital image processing stages. The study area was categorized into six main classes: agricultural land, meadow/pasture–unplowed land, bare/raw soil, forest, wetland, and settlement area. Supervised classification was employed for the identification and mapping of these classes.The findings indicate that the land use pattern in the Türkoğlu district has undergone a dramatic transformation from 1987 to 2024. Based on periodic comparisons (1987–1997, 1997–2007, 2007–2017, and 2017–2024), a significant decline was observed in agricultural lands, forests, and wetlands, while a rapid increase in settlement areas and an expansion in bare/raw soil areas were detected. The primary drivers of these changes are considered to be population growth, urban sprawl, transformation in agricultural activities, economic differentiation, and climatic variability. The thematic maps and statistical data generated as a result of this study serve as a strategic guide for sustainable land management and environmental planning processes in the region.</div