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HIV/HBV Coinfection with HBsAg Seroconversion: A Case Report
Get PDFMortality rates associated with human immunodeficiency virus (HIV) infection have declined with antiretroviral therapy, transforming HIV infection into a chronic disease. However, coinfections and opportunistic infections remain significant contributors to mortality and morbidity in individuals living with HIV. Since the transmission routes are similar, the coexistence of HIV and viral hepatitis infections is common. Human immunodeficiency virus infection and hepatitis B virus (HBV) infection affect the course of each other negatively. In this study, a patient with HIV-HBV co -infection who developed HBsAg seroconversion is presented
Investigation of incidental findings of temporomandibular joint disorders on brain magnetic resonance imaging in three-dimensional T2-weighted SPACE sequence performed for brain imaging
Get PDFObjectives: The study aimed to determine the temporomandibular joint (TMJ) findings, to investigate the prevalence contribution of this sequence on cases in which cranial magnetic resonance examination was performed and three-dimensional (3D) T2-SPACE (T2-weighted sampling perfection with application-optimized contrasts using different flip-angle evolutions) sequence was used by retrospectively scanning the magnetic resonance imaging (MRI) archive of our hospital, and to reveal the advantages of the 3D-T2 SPACE sequence in patients with TMJ disorders. Patients and methods: The cross-sectional retrospective study was conducted with 499 patients (289 females, 210 males; mean age: 50.1 +/- 17.7 years; range, 8 to 92 years) who underwent brain MRI and had 3D-T2 SPACE between March 1, 2021 and March 1, 2022. Two radiologists analyzed the TMJs of the subjects included in the study in 3D-T2 SPACE sequences. Results: At least one incidental finding was detected in the TMJ in 37.1% (n=185) of the patients included in our study. In our study, the most common (13.6%) MRI findings were osteoarthritic changes and synovial cysts. Joint effusion (13.2%) and disc displacement (9%) were less frequent. When the relationship between the age of the patients and the presence of incidental findings, degeneration, effusion, disc displacement, and cyst was examined, the age of the patients with incidental findings (p=0.001) and osteoarthritic changes (p<0.001) was statistically significantly higher. Conclusion: Incidental findings, particularly osteoarthritic changes and synovial cysts, can be seen quite commonly in the TMJ in brain MRI using 3D T2-SPACE sequences in the general population. The 3D T2-SPACE sequence provides valuable information in the recognition of TMJ disorders
NATO ve Şanghay İşbirliği Örgütü Üzerinden ABD ve Çin Rekabetinin Analizi
Get PDFSoğuk Savaş dönemi koşullarında güçlenerek ve kurumsallaşarak büyük bir tecrübe edinen NATO, genişlemeye ve derinleşmeye devam etmiştir. Süper güç ABD’nin örgüt içerisindeki öncü konumu, belirleyici etkisi devam etmektedir. Uluslararası sistemin dengeleyici unsurlarından birisi olmaya aday olan Çin ise kendi öncülüğünde ortaya çıkan ŞİÖ ile giderek gücünü ve kendisine olan ilgiyi artırmaktadır. ABD’nin NATO üzerinden etki ve müdahale sahasını genişletme arayışı Çin’i rahatsız etmektedir. Aynı şekilde Çin’in de ŞİÖ üzerinden etki alanını genişletme arayışı Batı dünyasında endişe ile takip edilmektedir. NATO, Çin’i direkt tehdit olarak algılamasa da ABD, Çin’i direkt tehdit olarak görmektedir. Her iki örgütünde başat aktörleri olan ABD ve Çin, var olagelen rekabetlerini her bir platformda yürüttükleri gibi NATO ve ŞİÖ üzerinden de yürütmektedirler. Çalışmada ABD ve Çin rekabeti, NATO ve ŞİÖ üzerinden incelenmiştir. ABD’nin NATO üzerinden Çin’i sınırlandırma arayışında olduğu, Çin’in ise kendi bölgesinde ABD’yi ŞİÖ üzerinden dengeleme ve var olan statükoyu ortadan kaldırmaya yönelik politikalar izlediği sonucuna ulaşılmıştır. NATO ve ŞİÖ mukayese edildiğinde ŞİÖ’nün NATO’nun alternatifi olabilecek potansiyele sahip olmaktan henüz uzak olduğu görülmüştür
Finite Element Analysis of AA6061/AA5754 Bimetallic Sheets by Constrained Groove Pressing
Get PDFConstrained groove pressing (CGP) is a severe plastic deformation method used for obtaining ultrafine-grained structures in sheet materials and alloys and for improving their mechanical properties. This study entailed a finite element analysis (FEA) of the CGP process with AA6061/AA5754 bimetallic sheets. The FEA was performed using 30°, 45°, and 60° groove angles; friction coefficients of 0.05, 0.1, and 0.2; and two types of contacts (free and fixed). The thicknesses of the AA6061 and AA5754 sheet materials used in the analysis were 0.8 mm and 1.2 mm, respectively. The analysis showed that the type of contact between the materials is very important and that the effective plastic strain increases as the channel angle increases. © 2024 selection and editorial matter, Amrut Mulay, Swadesh Singh and Andrzej Kocanda
Diversity of MHC class II DRB alleles in the Northern chamois genus Rupicapra
Get PDFMajor histocompatibility complex (MHC) genes are commonly used markers for monitoring adaptive genetic and evolutionary potential of species. In this study, we investigated genetic variation of the MHC class II DRB locus in the chamois genus Rupicapra by using next-generation sequencing. Sequencing of 102 samples led to the identification of 25 alleles, 11 of which are novel. The high ratio of the relative rates of nonsynonymous to synonymous mutations (dN/dS) suggests a signal of positive selection on this locus. We analyzed patterns of genetic variation within and among 2 subspecies of Northern Chamois and compared them to previously published studies using neutral markers to provide a basis for assessing the effects of demographic processes. Our analyses have shown that alleles are likely to be maintained by balancing selection in different populations with similar frequencies and that this mechanism also works in small, isolated populations that are strongly affected by genetic drift. In this study on the chamois genus Rupicapra, researchers explored genetic variation of the MHC class II DRB locus using next-generation sequencing. The research highlights a strong signal of positive selection at this locus, indicated by the high dN/dS ratio. The study also revealed that balancing selection maintains alleles across different chamois populations, including those that are small and isolated, emphasizing the evolutionary significance of this genetic mechanism. Graphical AbstractCroatian Science Foundation [2016-06-5751]; Slovenian Research Agency [P6-0064]; RESBIOS European Union [872146]This study was supported by (i) the Croatian Science Foundation, project IP 2016-06-5751, DNA as evidence of distribution and vitality of endangered Balkan Chamois; (ii) the Slovenian Research Agency (programme group P6-0064); and (iii) the RESBIOS European Union's Horizon 2020 Research and Innovation Program (no. 872146)
Ergonomic analysis of hospital workplace environment: the case of a public hospital in Düzce
Get PDFYapılan bu çalışma ile Düzce ilinde bir kamu hastanesinde çalışanlarca kullanılan mobilyaların ergonomik açıdan kullanıcıya uygunluğunun araştırılması hedeflenmiştir. Bu amaçla elde edilen ve yorumlanan veriler ile hastane çalışanlarının kullandıkları mobilyaları daha ergonomik kullanımına imkân sağlanmıştır. Çalışma kapsamında hemşire, ebe, sağlık memuru ve polikliniklerde görevli çalışanlardan oluşan 242 çalışana yüz yüze görüşme yöntemiyle ulaşılmış ve veri alınmıştır. Elde edilen verilerin istatistiksel değerlendirilmesi sonucunda katılımcıların %26,4’ünün ergonomik çalışma koşulları konusunda herhangi bir bilgilerinin olmadığı, %45 oranında ise kısmen bilgilerinin olduğu belirlenmiştir. Katılımcıların çalışma alanlarının ergonomik tasarımları ile ilgili olarak en çok memnuniyet duydukları durum gerekli görülen yerlerde yeterli miktarda antiseptik ve dezenfektan maddesinin varlığıdır. Bunun yanında katılımcılar mahremiyeti sağlamak için gerekli bölmelerin varlığından, çalışma alanlarının düzenli temizliğinin yapılmasından, çalışma alanlarının yeterince aydınlatılmasından da memnuniyet duymaktadırlar. Katılımcıların elektrik kablolarının güvenli bir şekilde toplanıp toplanmamasından, oturulan koltukların uygun olup olmamasından, ofis sıcaklığının uygun olup olmamasından en az düzeyde rahatsızlık duydukları belirlenmiştir. Çalışma kapsamında çalışanların çalışma ortamlarına bağlı olarak yaşadıkları en temel sağlık sorunlarının genel yorgunluk ve bitkinlik hissi olduğu, bunu bel ve sırt ağrıları ve stresin takip ettiği tespit edilmiştir
Gender and circadian preferences influence emotions and motivation in secondary mathematics classrooms
Get PDFMany studies have reported poor school achievement in evening persons and general circadian fluctuations in cognition. The aim of this study was to analyze circadian fluctuations in a cross-sectional design and examine the effects of chronotype on situational emotions and intrinsic motivation. A cross-sectional survey study was conducted in three Turkish secondary schools with a total sample of 599 students (283 females and 316 males). Data were collected at the end of specific math lessons of the same grade level and content, using a form combining three scales. We found no gender-related differences in intrinsic motivation, while there were some differences in situational motivation. In math classes, female students exhibited higher level of interest, while boys scored higher on boredom. In addition, students who scored high on morning affect reported higher levels of interest, well-being, and less boredom. Students with higher stability (and lower fluctuations in mood and cognition during the day) reported a higher degree of enjoyment, perceived competence, perceived choice, and less pressure/tension in their math lessons. A positive association was observed between distinctness, interest, and well-being, while negative correlations existed between distinctness and boredom. This suggests that students with higher diurnal stability reported a higher level of interest, well-being, and a lower level of boredom. Additionally, the results of the analyses showed that morningness, distinctness, and eveningness were significant predictors of intrinsic motivation. Conversely, gender, time of application, morningness, and distinctness emerged as predictors for situational emotions in mathematics classes
Radiologic and histopathologic effects of favipiravir and hydroxychloroquine on fracture healing in rats
Get PDFFracture healing is a process in which many factors interact. In addition to many treatments, physical and biological therapy methods that affect different steps of this process, there are many biological and chemical agents that cause fracture union delay. Although the number of studies on fracture healing is increasing day by day, the mechanism of fracture healing, which is not fully understood, still attracts the attention of all researchers. In this study, we aimed to investigate the effects of favipiravir and hydroxychloroquine used in the treatment of COVID-19. In this study, 48 male Wistar rats weighing 300 +/- 50 g were used. Each group was divided into eight subgroups of six rats each to be sacrificed at the 2nd and 4th weeks and evaluated radiologically and histologically. Favipiravir (group 1), hydroxychloroquine (group 2), favipiravir + hydroxychloroquine (group 3), and random control (group 4) were used. A statistically significant difference was observed between the 15th day histological scoring averages of the groups (p 0.05), we obtained different results in terms of complete bone union distributions and radiological images of the fracture line. Although favipiravir has a negative effect on fracture union in the early period, favipiravir may have a positive effect on fracture union in the late period. We did not find any effect of hydroxychloroquine on fracture union.Duzce UniversityNo Statement Availabl
Effect of Bacterial Nanocellulose and Plant-Containing Facial Serum on Hyperpigmentation in in-vitro Conditions
Get PDFThis study investigated the effect of some herbal extracts, such as licorice root, white mulberry leaf, green tea leaf, and grape seed, with a combination of bacterial nanocellulose and some bioactive materials, such as ascorbic acid, niacinamide, hexylresorcinol, and alpha-arbutin, on treatment of hyperpigmentation. The effect of the prepared emulsions on hyperpigmentation was revealed by analyzing their tyrosinase inhibition properties, their ability to stop melanin production, or their properties of whitening the brown spot on the skin. In addition to the physicochemical properties of the 5 different emulsions obtained, tyrosinase, collagenase, and elastase enzyme activities, antioxidant properties, cytotoxicity, and microbiological analyzes were performed by cell-culture modelling. Finally, a dermocosmetic facial serum was designed that is compatible with skin pH, is homogeneously mixed, has good spreading properties, does not cause any microbiological growth, does not inhibit elastase activity while stimulating collagenase activity, reduces melanin production by inhibiting the tyrosinase enzyme, and does not have any toxic effects
Evaluation of machining characteristics of SiO2 doped vegetable based nanofluids with Taguchi approach in turning of AISI 304 steel
Get PDFIn this study, nanofluids prepared by incorporating silicon dioxide (SiO2) nanoparticles into sunflower oil were used as cutting fluids for turning AISI 304 stainless steel. Dynamic viscosities and thermal conductivities of nanofluids prepared at two different concentrations (1 % and 0.5 % by volume) were measured at four different temperature conditions. The experiments were carried out in two stages: main experiments and additional experiments. In the main experiments, four different cooling conditions (dry, PureMQL, 0.5 % NanoMQL, 1 % NanoMQL), four different cutting speeds (80, 120, 160, 200 m/min), and four different feed rates (0.10; 0.15, 0.20, 0.25 mm/rev) were used. In additional experiments, the effect of 4 different cooling methods on machining performance was investigated by keeping the maximum cutting speed (200 m/min) and feed rate (0.25 mm/rev) constant. In all experiments, workpiece surface roughness (Ra), temperature in the cutting zone (T), and flank wear on cutting tools (Vb) were determined as performance criteria. Also, additional experiments were repeated 45 times, and wear was measured every ten experiments to get a clearer picture of the tool wear process. At the end of the study, it was determined that the most effective parameter on surface roughness was feed rate (76 %), while the temperature in the cutting zone and tool wear were mainly affected by the cooling method (80 % and 50.5 %, respectively). The best machining performance was observed in the 0.5 % nanoMQL method.Zonguldak Buelent Ecevit University Scientific Research Projects Unit [2020-77654622-02]The authors would like to thank the Zonguldak Buelent Ecevit University Scientific Research Projects Unit for supporting this study. (Project Number: 2020-77654622-02). Also, the authors would like to thank the Duezce University for the possibility of using machines and equipment in their experiments