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Weak π-Rickart rings
No full textThis paper introduces and studies the weak pi-Rickart ring property, which represents a new extension of the Rickart ring condition. Regularity, extending and prime-like conditions for the weak pi-Rickart rings are defined and shows the implications between these conditions and their links with Rickart, p.q.-Baer, regular and biregular conditions. We include applications to polynomial and formal power series extensions and to triangular matrix rings, with examples given to demonstrate the results
Determination of physicochemical and functional properties of red peppers which collected from different regions
No full textBölgesel farklılıklar, gıdaya özgü karakteristik yapıyı oluşturmaktadır. Gıdanın sahip olduğu karmaşık kimyasal yapısının gelişmiş analitik teknikler kullanılarak detaylı bir şekilde analiz edilmesi ile elde edilen verilerin istatistiksel yöntemler kullanılarak anlamlandırılması ve yetiştirildiği orijin ile ilişkilendirilmesi; pazar içerisinde rekabet edilebilirliğini arttırmakta ve bölgesel üretimin sürdürülebilirliğine katkı sağlamaktadır. Bu tez kapsamında, Türkiye'nin farklı bölgelerinden toplanan kırmızıbiber numunelerinin fizikokimyasal özellikleri (pH, toplam asitlik, toplam kuru madde, renk, askorbik asit), antioksidan kapasite ve toplam fenolik madde miktarı, kapsaisinoid ve karotenoid içerikleri ve spektroskopik parmak izi taraması (FT-IR) yapılarak kırmızıbibere ait karmaşık kimyasal kompozisyon ortaya konulmuştur. Ayrıca, bölgeler arası farklılıklar, ileri düzey istatistiksel yöntemlerden kemometrik yaklaşımla değerlendirilmiştir. Toz kırmızıbiberlerin % 91,85-97,66 toplam kuru madde; 4,99-5,53 pH; % 2,58-4,80 toplam asitlik; L* değerleri, 51,56-66,20; a* değerleri, 13,11-27,92; b* değerleri, 17,59-36,40; 618,47-2379,12 mg/100g KM askorbik asit içeriğine sahip olduğu görülmüştür. Antioksidan kapasiteleri; DPPH metodu ile 1,20-7,82 μmol TE/g KM, CUPRAC metodu ile 105,24-836,49 μmol TE/g KM düzeyinde saptanmıştır. Örneklerin toplam fenolik madde miktarı ise 446-540 mg GAE/100 g KM aralığında saptanmıştır. En yüksek toplam kapsaisinoid içeriğine (337,71 mg/kg KM) sahip olan Kahramanmaraş kırmızıbiberi, diğer illere kıyasla istatistiksel olarak anlamlı farklılık göstermiştir. Karotenoid düzeyleri bakımından; Gaziantep acı kırmızıbiberi, β-karoten (63,79 mg/kg KM) ve likopen (1,81 mg/kg KM) içeriğiyle; Bursa acı kırmızıbiberi ise, lutein (0,90 mg/kg KM) içeriğiyle diğer illere kıyasla istatistiksel farklılık göstermektedir. Ayrıca, kırmızıbiberlerin kimyasal yapısının ve fonksiyonel özelliklerinin FT-IR ölçümleri ile bölgeler arasında anlamlı farklılıklar gösterdiği belirlenmiştir.Regional differences constitute the characteristic structure specific to food. By analyzing the complex chemical structure of food in detail using advanced analytical techniques, the data obtained is interpreted using statistical methods and associated with the origin where it is grown; increases the competitiveness in the market and contributes to the sustainability of regional production. Within the scope of this thesis, the physicochemical properties (pH, total acidity, total dry matter, color, ascorbic acid), antioxidant capacity and total phenolic substance amount, capsaicinoid and carotenoid contents and spectroscopic fingerprint scanning (FT-IR) of red pepper samples collected from different regions of Turkey were revealed by complex chemical composition of red pepper. In addition, the differences between the regions were evaluated by chemometric approach, which is one of the advanced statistical methods. Red peppers powder had 91.85-97.66% total dry matter; 4.99-5.53 pH; 2.58-4.80% total acidity; L* values, 51.56-66.20; a* values, 13.11-27.92; b* values, 17.59-36.40; 618.47-2379.12 mg/100g DM ascorbic acid content were found. Antioxidant capacities were determined as 1.20-7.82 μmol TE/g DM by DPPH method and 105.24-836.49 μmol TE/g DM by CUPRAC method. Total phenolic substance amount of the samples was determined in the range of 446-540 mg GAE/100 g DM. Kahramanmaraş red pepper having the highest total capsaicinoid content (337.71 mg/kg DM) showed statistically significant difference compared to other provinces. In terms of carotenoid levels; Gaziantep hot red pepper shows statistical differences with its β-carotene (63.79 mg/kg DM) and lycopene (1.81 mg/kg DM) content; Bursa hot red pepper shows statistical differences with its lutein (0.90 mg/kg DM) content compared to other provinces. In addition, it was determined that the chemical structure and functional properties of red peppers showed significant differences between the regions with FT-IR measurements
Bioconvergence of sound-guided and supramolecular assembly strategies to create peptide-protein composite hydrogels with predictable shape-to-function features
No full textPurely protein-based hydrogels are widely used in tissue engineering for their biomimicry and biocompatibility, yet remain challenging to tailor with precision and predictability at biological and mechanical levels. To overcome this, synthetic self-assembling peptide amphiphiles (PAs) offer opportunities for supramolecular customization, both as single-phase materials and co-assembled with proteins to create hybrid nanocomposites with emerging functionalities. Similarly, contactless, sound-guided bioassembly techniques using liquid-phase hydrogel precursors are emerging as strategic tools for obtaining structured and functional hydrogels. Leveraging these advances, here a fast, contactless, 'one-pot' bioassembly strategy merging supramolecular PA self-assembly with sound-guided patterning to fabricate hybrid peptide-protein hydrogels with predictable, shape-dependent functionality is presented. Using fibrin as proof-of-concept, material performance is biologically enhanced by incorporating growth factor-binding PAs, while inorganic microparticles are embedded and spatially organized via acoustic fields to tune mechanical properties. This strategy allows predictable tuning of composite stiffness and architecture by adjusting sound wave frequency, with acoustic fields guiding material organization from nano-to-macroscale. Composite hydrogels result highly permissive to cell infiltration in vitro and versatile platforms to tune immune cell-material interactions. This modular biofabrication platform integrating supramolecular and sound-guided processes can be generalized to other building blocks, opening unique opportunities for scalable, tunable, and hierarchically-organized biomaterials.University of NottinghamAO FoundationCharlotte Martin Foundation--AOCMF-21-04SUK Regenerative Medicine Platform -- MR/R015651/
Progressive collapse behaviour of reinforced concrete buildings under multiple column loss: Influence of slab type and beam depth
No full textProgressive collapse, a chain reaction of failures initiated by the loss of a key load-bearing component, poses severe risks to reinforced-concrete (RC) buildings under blasts, earthquakes, or accidental overloads. This study investigates how slab type (two-way solid vs. two-way ribbed) and beam depth influence the progressive-collapse resistance of multistorey RC structures. A six-story war-damaged RC building, where four ground-floor columns were destroyed, was first analysed to validate the numerical modelling. Field surveys recorded a vertical displacement of approximately 130 mm, while the Applied Element Method (AEM)–based Extreme Loading for Structures (ELS) software predicted 120–132 mm, confirming strong agreement and compliance with UFC 4-023-03 criteria. Following validation, a parametric study was conducted on 9-, 12-, and 15-story RC buildings subjected to three critical column-removal scenarios: (1) corner-and-penultimate removal, (2) three exterior mid-span removals, and (3) three interior column removals. Beam depths of 500, 600, and 700 mm were examined for each slab configuration. Results show that ribbed slabs provided superior robustness, maintaining stability even with the smallest beam depth, while solid slabs required depths ≥700 mm to prevent collapse. Ribbed slabs also exhibited greater energy dissipation through catenary and tensile-membrane action, producing smaller displacements and plastic rotations within UFC rotation limits. The study's novelty lies in integrating real-world validation with a systematic AEM-based parametric analysis across multiple building heights and failure scenarios. The results provide actionable guidance for performance-based design strategies to enhance the progressive-collapse resilience of mid-to high-rise RC buildings
Lokal ileri yinelemiş bazal hücreli karsinom tanılı bir olguda eşzamanlı vismodegib ve hipofraksiyone stereotaktik radyoterapi: Olgu sunumu
No full textIn this study, we present a patient with recurrent basal cell carcinoma (BCC) located in a high-risk area of the face who was treated with a combination of vismodegib and hypofractionated stereotactic radiotherapy (hSRT). Targeted therapies such as hedgehog pathway inhibitors play an important role in the treatment of advanced BCC, but the duration of response is limited due to resistance. The combination of hedgehog pathway inhibitors and radiotherapy has the potential to achieve a durable and effective therapeutic response, particularly in patients with locally advanced disease. A 68-year-old male patient had a recurrent mass localized to the nasal dorsum and extending to the medial canthus of both eyes, infiltrating the nasal and maxillary bones. Multiple biopsies taken from the lesion edges reported infiltrative BCC and basosquamous cell carcinoma foci. The patient responded well to vismodegib, but surgery was not considered. Considering the tolerance of the organs at risk, concurrent 4200 centigray/14 fractions hSRT was applied with the CyberKnife-M6 device. Acute grade 1 to 2 toxicity was observed during treatment. At the end of treatment, the mass regressed, ptosis in the left eye decreased, and the visual field expanded. Complete radiological and clinical response was achieved four months after treatment. Combination therapy was found to be effective in a patient with recurrent locally advanced BCC. The combination of vismodegib and hSRT should be evaluated in prospective studies.Bu çalışmada, vismodegib ve hipofraksiyone stereotaktik radyoterapi (hSRT) kombinasyonu ile tedavi edilmiş olan yüzün yüksek riskli bölgesinde yerleşmiş yinelemiş bazal hücreli karsinom (BHK)’ lu bir hasta sunulmaktadır. Hedgehog yolu inhibitörleri gibi hedeflenmiş tedaviler, ileri evre BHK tedavisinde önemli bir rol oynar, ancak direnç nedeniyle yanıt süresi kısadır. Hedgehog yolak inhibitörleri ve radyoterapinin kombinasyonu, özellikle lokal ileri evre hastalarda kalıcı ve etkili bir tedavi yanıtı sağlama potansiyeline sahiptir. 68 yaşında bir erkek hastada, nazal dorsuma lokalize ve her iki gözün medial kantusuna kadar uzanan, nazal ve maksiller kemikleri infiltre eden nüks kitle mevcuttu. Lezyon kenarlarından alınan çoklu biyopsiler, infiltratif BHK ve bazoskuamöz hücreli karsinom odakları şeklinde raporlanmıştı. Vismodegib’e iyi yanıt veren hastaya cerrahi düşünülmemişti. Risk altındaki organların toleransı göz önüne alınarak CyberKnife-M6 cihazı ile eşzamanlı 4200 santigray/14 fraksiyon hSRT uygulandı. Tedavi sırasında akut derece 1-2 toksisite gözlendi. Tedavi sonunda kitle geriledi, sol gözdeki pitozis azaldı ve görme alanı genişledi. Tedaviden 4 ay sonra radyolojik ve klinik tam yanıt elde edildi. Tekrarlayan lokal ileri evre BHK’lu bir hastada kombine tedavi etkin bulundu. Vismodegib ve hSRT kombinasyonu ileri prospektif çalışmalarla değerlendirilmelidir
Endoparasites of the Bridled Mabuya, Heremites vittatus (Olivier, 1804 (Squamata: Scincidae) from Türkiye
No full textNinety-five bridled mabuya, Heremites vittatus (37 males, 49 females, and 9 juveniles) collected throughout Turkiye were examined for helminths. One species of trematode, Plagiorchis elegans; 1 species of cestode, Mesocestoides sp.; and 5 species of nematode, Parapharyngodon sp., Skrjabinodon pigmentatus, Spauligodon aloisei, Spauligodon eremiasi, and Thubunaea sp. were found. One new locality record and 7 new host records are reported
Intestinal endometriosis amongst other extra-pelvic endometriosis foci presenting as acute/subacute bowel obstruction in women of reproductive age: a retrospective case series study
No full textBackground: This study aimed to investigate the prevalence and clinicopathological correlates of intestinal endometriosis, amongst other extra-pelvic endometriosis foci, presenting as bowel obstruction in general surgery practice. Methods: A total of 23 female patients (mean ± SD age: 34.9 ± 6.5 years) who underwent abdominal surgery for acute bowel obstruction and received histopathological diagnosis of endometriosis were included in this retrospective case-series study. Data on patient characteristics, obstetric history, preoperative laboratory and imaging findings, preoperative provisional diagnosis, type of surgical intervention and the pathological diagnosis, and postoperative outcomes were recorded. Results: Definitive diagnoses on histopathological work-up involved intestinal endometriosis (52.2%), scar endometriosis (26.0%), ovarian endometriosis (13.0%) and inguinal endometriosis (8.7%). Postoperative complication, reoperation and recurrence rates were 8.7%, 8.7%, and 13.0%, respectively. Intestinal endometriosis, when compared to other extra-pelvic endometriosis foci (scar and inguinal), was associated with significantly higher preoperative platelet counts (332.0(284.0-528.0)vs. 239.0(223.0-370.0) 103/µL, p = 0.010), lower albumin levels (4.0(2.7–4.7) vs. 4.5(4.2–4.9) g/dL, p = 0.029), higher rates of preoperative CT utilization (91.7% vs. 0.0%, p < 0.001) and emergent surgery (83.3% vs. 0.0%, p = 0.001) and longer LOS (median 4.5 (1.0–26.0) vs. 1.0(1.0–1.0) days, p = 0.001) along with a non-significant tendency for higher postoperative complication (16.7% vs. 0.0%) and ICU stay (25.0% vs. 0.0%) rates. Conclusion: Our findings revealed intestinal endometriosis, predominantly in the terminal ileum/appendix, was the most common extra-pelvic cause of acute bowel obstruction. The scar endometriosis, inguinal endometriosis and ovarian endometriosis appeared to be other potential but less prevalent aetiologies in this setting
Substituent Effects Govern the Efficiency of Isoxazole Photoisomerization to Carbonyl-2H-Azirines
No full textThe photoisomerization of isoxazoles is an atom-economical route to carbonyl-2H-azirines, which are valuable in both synthetic and biological applications. However, isolation of the carbonyl-2H-azirine is challenged by reverse photoisomerization back to the isoxazole and irreversible rearrangement to an oxazole. In this work, we demonstrate that substituent selection on 3,5-disubstituted isoxazoles plays a critical role in driving the photochemical isoxazole–azirine equilibrium toward the carbonyl-2H-azirine while avoiding oxazole formation. We find that substituents affect the degree of overlap in the absorption spectra of isoxazole–azirine pairs, where reducing overlap increases the efficiency of photoisomerization. We use time-dependent density functional theory to predict absorption spectra for isomer pairs with varied 3,5-disubstituents, identifying tert-butyl- and trifluoromethyl-substituted 5-aminoisoxazoles as promising structures. We then tested these predictions experimentally, revealing efficient formation of carbonyl-2H-azirines in high yields with minimal oxazole formation. This is in contrast to a phenyl-substituted 5-aminoisoxazole, which was found to readily form oxazoles, precluding isolation of the carbonyl-2H-azirine. These results demonstrate the utility of substituent-driven design for tuning photoisomerization equilibria and provide an atom-economical option for generating carbonyl-2H-azirines on synthetically useful scales.Version of Recor
A review of data linkages for policy-informing research in food and agricultural economics
No full textResearchers commonly use linked data as an empirical tool because information relevant to answer policy questions is often dispersed across multiple sources. To understand how linked data are used in food and agricultural economics research, we conducted a systematic review of 104 peer-reviewed articles, published between 2000 and 2020, in which authors combine data sources to conduct their intended analyses. With our sample of papers, we classify types of data used, describe linkage methods, and summarize empirical approaches. Results show that most studies use public data, and many apply causal methods to examine food policy questions. These patterns highlight the value of public data and the role of linked datasets in food and agricultural economics research. Continued investment in data access, infrastructure, and shared practices for managing and analyzing integrated datasets can strengthen and expand the use of linked data in future research.Version of Recor
