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Effect of genotype x season interaction on yield and quality traits in hybrid and standard summer squash (cucurbita pepo l.) cultivars
No full textBackground: Climate change has become a crucial factor affecting the timing and success of vegetable cultivation, especially in regions like the eastern Mediterranean where temperature and precipitation patterns are shifting. Summer squash (Cucurbita pepo L.), typically grown in warm seasons, is an important export crop in the Mersin province of Turkey. However, few studies have examined its performance under different seasonal conditions. Methods: This study aimed to compare the yield and fruit quality traits of five hybrid (Alba F1, Amelthee F1, Hadra F1, Hurrem F1, Vildan F1) and five standard [Pelin, Nazli (S), Black Squash Elite, Eskenderany, White Bush] summer squash cultivars grown in spring and autumn. The experiment was conducted under open-field conditions in Tarsus, Mersin in 2022 using a randomized plot design. Key yield parameters (fruit weight, fruit length, fruit diameter, number of fruits per plant, total yield) and quality traits (fruit flesh hardness, water-soluble dry matter, fresh and dry fruit weights) were evaluated using two-way ANOVA. Result: Spring cultivation produced significantly higher yields (2595.12 g/plant) than autumn (635.51 g/plant), due to more favorable environmental conditions. 'Vildan F1' had the highest yield in both seasons, while 'Hadra F1' and 'Pelin' were notable for fruit firmness and size. Although spring cultivation remains advantageous, autumn conditions increased dry matter content, suggesting potential benefits under future warming. These findings underline the importance of cultivar selection and seasonal planning for sustainable squash production and export continuity amid climate change
Effect of tadalafil on testicular histology and sperm parameters in an experimental varicocele model
No full textObjectives Varicocele is a common cause of male infertility, often associated with oxidative stress and impaired testicular blood flow. This study aimed to evaluate whether orally administered tadalafil, through its cGMP-mediated vasodilatory and antioxidant effects, can protect against histological damage and altered sperm parameters in a rat model of experimental left varicocele. Methods Twenty-four male rats were assigned to three groups: control-sham (Group 1), left varicocele (Group 2), and left varicocele with daily oral tadalafil administration (Group 3; 1 mg/kg/day by oral gavage). After 75 days, left testicular tissues were harvested for histopathological and apoptotic analysis, and sperm samples were collected from left epididymal tissues. Histopathological evaluation was conducted using the modified Johnsen score, and apoptosis was assessed by the apoptotic index. Sperm count, motility, acrosomal defects, and morphological defects were also analyzed. Results In our study, Group 2 (varicocele) showed significantly lower modified Johnsen scores (p = 0.005) and sperm motility (p = 0.042), and a higher apoptotic index (p < 0.001) compared to Group 1 (control-sham). Compared to Group 2, tadalafil treatment in Group 3 significantly improved sperm motility (p < 0.001) and reduced the apoptotic index (p = 0.004), while the increase in Johnsen score was not statistically significant (p = 0.140). The thickness of the tunica media layer was significantly higher in Groups 2 (p = 0.008) and 3 (p = 0.004) compared to Group 1, while no difference was observed between Groups 2 and 3. Conclusion Tadalafil demonstrates potential efficacy in preserving testicular tissue and maintaining sperm parameters against damage induced by varicocele. These findings support further investigation into the role of phosphodiesterase type 5 (PDE5) inhibitors as adjunctive agents in male reproductive health
Effects of major drying methods on the stability and retention of vitamin c, b group vitamins, fat-soluble vitamins, and carotenoids in kiwifruits
No full textThis study investigates the effects of five drying methods-freeze, vacuum, microwave, convective, and natural-on the nutritional and visual quality of kiwifruit, focusing on the vitamin C, B-group vitamins, fat-soluble vitamins, and carotenoids. Fresh samples contained 5.57 mg/g ascorbic acid, and freeze drying retained the highest level (3.13 mg/g), followed by vacuum drying (2.63 mg/g), while natural and convective drying resulted in severe reductions (1.06 and 1.21 mg/g). Riboflavin, initially 1.59 mu g/g, decreased to 0.91 mu g/g after freeze drying, 0.82 mu g/g after vacuum drying, and 0.54 mu g/g under natural drying. Carotenoids followed similar trends, with beta-carotene declining from 2.88 mu g/g in fresh samples to 2.24 mu g/g after freeze drying and below 1 mu g/g with natural drying. Freeze and vacuum drying best preserved vitamin content and color by minimizing oxidation and thermal damage, whereas natural and convective drying led to greater losses due to prolonged heat exposure and oxidative stress. Color changes strongly correlated with nutrient degradation. Notably, Delta E was negatively associated with ascorbic acid (-0.96) and thiamine (-0.95), while hue angle correlated positively with carotenoids and fat-soluble vitamins. These results show that color parameters reliably indicate nutritional retention, offering a practical approach for quality assessment in dried fruits
A retrospective investigation of emergency department revisits in Turkish older patients
No full textObjective: This study aims to examine the healthcare services received by adults aged 65 and over who visit the emergency department within 30 days of being discharged from their index admission, and it aims to establish a relationship between the healthcare services received and the revisits. Methods: Data were collected from the electronic records of 36,205 older patients who revisited the emergency department of a public training and research hospital. Patients were classified as "revisiting" if they returned to the ED within 30 days of discharge from their index visit. Descriptive statistics were used to summarize patient characteristics. Binary logistic regression assessed the impact of triage tag color, prior hospital visits, and outpatient clinic utilization on ED revisits. Results: Patients with a red triage tag were over six times more likely to be hospitalized than those with a yellow tag. Those who had visited the hospital within the previous 30 days were 37% more likely to return to the emergency department. Outpatient visits to internal medicine, cardiology, and pulmonology clinics increased revisit likelihood by 94%, 142%, and 244%, respectively. Conversely, patients receiving home healthcare were 65% less likely to revisit the emergency department. Conclusion: Outpatient service utilization are strongly associated with emergency department revisits among older adults. Enhancing access to primary care and improving coordination between specialists and family physicians may reduce unnecessary emergency department utilization. Policymakers should prioritize expanding primary care services and implementing remote follow-up systems to support continuity of care
The dynamical landscape of the negative-order (3+1)-dimensional calogero-bogoyavlenskii-schiff equation
No full textA new negative-order form of the (3 + 1)-dimensional Calogero-Bogoyavlenskii-Schiff equation is examined in this investigation. This equation plays an important role in accurately describing the thermodynamic properties of mixtures, particularly in chemical engineering applications. Through the use of wave transformations, the model is reduced to a nonlinear differential equation. To obtain exact solutions, two recently developed analytical techniques, namely the Riccati modified extended simple equation method and the generalized projective Riccati equation method, are applied. The solutions derived take the form of hyperbolic, trigonometric, and rational functions, representing different patterns of solitary wave profiles. By assigning specific values to the constants involved, corresponding three-dimensional, two-dimensional, and density plots are generated. In addition, the dynamical system associated with the model is constructed and carefully analyzed through bifurcation analysis, computation of Lyapunov exponents, investigation of quasiperiodic waves, exploration of chaotic behavior, and sensitivity analysis, all illustrated with relevant graphical representations. The study shows that the adopted methods are well suited to the considered model, and the results provide a useful foundation for further research in a wide range of scientific fields.Qassim University
QU-APC-202
Phoenixin-14 ameliorates ovarian morphology in a dhea-induced rat model of pcos
No full textPolycystic ovary syndrome (PCOS) is a complex reproductive-endocrine disorder characterized by impaired folliculogenesis, anovulation, and hormonal imbalance. While PNX-14 is known as a hypothalamic peptide that modulates GnRH signaling, emerging evidence indicates its local ovarian expression, particularly in granulosa and luteal cells, suggesting potential peripheral roles in follicular development. This study aimed to evaluate the therapeutic potential of PNX-14 in a dehydroepiandrosterone (DHEA)-induced rat model of PCOS, with a focus on its potential peripheral effects on ovarian tissue. Female rats were divided into control, PCOS, and PCOS + PNX-14 (2.5, 5, or 30 nmol) groups. PCOS was induced by DHEA administration (60 mg/kg/day, s.c.) for 21 days. Vaginal cytology, hormone assays (FSH, LH, E2, P4, and testosterone), histological analysis, PCNA immunohistochemistry, and western blot were performed. DHEA-induced PCOS rats exhibited disrupted estrous cycles, suppressed gonadotropins and estradiol, and polycystic ovarian morphology with extensive follicular atresia and reduced PCNA expression. PNX-14 treatment, particularly at 5 nmol, significantly improved estrous cyclicity, restored primordial and antral follicle populations, reduced atretic and cystic follicles, and normalized PCNA levels in granulosa cells. Serum hormones showed trends toward recovery without consistent statistical significance after 3 days of treatment. This study provides the first in vivo evidence that peripheral administration of this peptide ameliorates key morphological and cellular features of PCOS in rats, primarily by enhancing granulosa cell proliferation and early folliculogenesis. These findings support further investigation into PNX-14 as a novel therapeutic candidate as a local ovarian modulator for PCOS, potentially offering disease-modifying effects beyond conventional symptom-targeted therapies.Lay summaryPCOS is a leading cause of infertility and affects millions of women worldwide. It disrupts normal egg development, causing hormonal imbalances and cyst formation in the ovaries. Current treatments mainly control symptoms but do not repair the ovary itself. We investigate PNX-14, a natural peptide present in the brain and ovary that supports early egg growth. We tested this peptide found in the brain and ovary that supports early egg growth, in a well-established rat model of PCOS. After three days of treatment, it improved ovarian structure and restored regular reproductive cycling. Importantly, it significantly reduced degenerating follicles, helping to preserve healthy early-stage follicles. These benefits occurred even though major blood hormone levels were largely unchanged, suggesting that this peptide acts locally within the ovary. This is the first in vivo evidence that it can directly counter key cellular and structural damage caused by PCOS. The findings highlight PNX-14 as a potential new therapy to protect ovarian health and improve fertility in people with PCOS
An approach to modified grinding aid for green cement production: Synthesis, characterization, and compatibility with cement
No full textThis study presents a novel sustainable materials chemistry approach for enhancing cement performance by chemically modifying conventional based grinding aids (GAs). Amine- and glycol-based grinding aids (GAs), namely triisopropanolamine (TIPA), diethanol isopropanolamine (DEIPA), and diethylene glycol (DEG), underwent reactions with organic acids of different chain lengths to tailor their molecular structures and improve multifunctionality. The structural characterization of the modified GAs was conducted using Fourier-transform infrared spectroscopy. They were evaluated for their effects on cement grinding efficiency, particle size distribution, paste and mortar rheology, and mortar strength development. Compared with commercial counterparts, the modified GAs improved early-age compressive strength and rheological properties of cementitious pastes and mortars while also enhancing compatibility with polycarboxylate ether (PCE) based water-reducing admixtures was, especially for TIPA- and DEIPA-based systems. Modified GA systems significantly improved cement rheology and flow retention compared to the control and unmodified formulations. TIPA GA made with hexanoic acid exhibited the strongest effect, reducing viscosity by 21-86%, while DEG GA made with acetic acid achieved reductions of 5-69%. DEIPA modifications enhanced cement-PCE compatibility, leading to superior rheological behavior relative to unmodified DEIPA. Furthermore, TIPA, DEIPA, and DEG GAs made with each of propanoic acid, hexanoic acid, and propanoic acid, respectively, increased the 60-minute relative flow values by up to 15%, demonstrating improved workability retention. This advancement in research mitigates well-known admixture incompatibility issues and enables increased pozzolan incorporation without compromising workability or strength
Alternatives to mitigate the inferior performance of wet-mix shotcrete containing high recycled fine aggregate replacement rates
No full textThe thixotropy, shootability, and mechanical properties of wet-mix shotcrete (WMS) mixtures with high replacement rates of recycled fine aggregate (RFA) of 75% and 100% are examined in this study. Four different alternatives including reduced free mixing water and addition of metakaolin (MK), thixotropy enhancing agent (TEA), and polypropylene fibres (PPF) are evaluated in order to improve the WMS properties. Test results demonstrated that the build-up thickness improved by 1.3- to 2-folds with the incorporation of MK, PPF, and TEA, reflecting their suitability to overcome the inferior shootability at high RFA additions. The TEA significantly increased the development of thixotropy, which was ascribed to the chemical reactions that create a gel and dense network structure. The use of 1% TEA in the mix containing 75% RFA increased by 64% the thixotropic initial shear stress. Nevertheless, this was accompanied with the highest drop in strength, requiring proper tailoring of the dosage rate and mortar composition. Mixtures prepared with reduced water-to-binder ratio from 0.45 to 0.4 compensated the drop in strength due to high RFA rates. Yet, this alternative is not an efficient to counterbalance the decline in shootability, given the increased superplasticizer demand that promotes bleeding and sagging despite the high thixotropy
Teaching english and the environment to efl young learners in Turkey
No full textThis paper reports on a part of a larger practitioner research project focused on integrating environmental issues through critical language pedagogy into a young learner's classroom in Turkey. Drawing on Paulo Freire's problem-posing model grounded in critical pedagogy, the authors developed localized materials, and a pedagogic model rooted in six environmental themes derived from the students' lived experiences. The pedagogic model was implemented in a public primary setting with a group of fourth-grade students. Semi-structured interviews were conducted with the students to understand the model's effectiveness in achieving its dual objectives: development of language and critical environmental awareness. The purpose of this paper is to present a theory-driven, practical, pedagogic model for practitioners seeking to develop their context-sensitive environmental ELT pedagogies
Effect of austenitizing heat treatment on microhardness and corrosion resistance of 1.4116 martensitic stainless steel
No full textMartensitic stainless steels are utilized in applications requiring high hardness, low wear, and elevated corrosion resistance. Owing to their high alloying element content, they can be hardened through heat treatment. To achieve the desired mechanical properties and corrosion resistance, heat treatment parameters must be appropriately selected; the ratios of martensite, carbide, and retained austenite in the microstructure should be balanced. In this study, temperature and time parameters in the austenitizing heat treatment of 1.4116 (X50CrMoV15) martensitic stainless steel, commonly used in the knife manufacturing industry, were experimentally investigated to obtain an optimal microstructure, maximum hardness, and high corrosion resistance. Temperature values of 1,000 degrees C, 1,020 degrees C, 1,040 degrees C, 1,080 degrees C, 1,100 degrees C, and 1,120 degrees C, as well as durations of 180 s, 210 s, and 260 s, were examined. At lower temperatures, insufficient hardness was achieved due to incomplete austenite transformation and partial dissolution of carbides. At higher temperatures, grain coarsening and retained austenite formation led to a decrease in hardness. At the optimal temperature of 1,080 degrees C, significant carbide dissolution occurred, complete austenite transformation was achieved, and high-carbon martensite was formed, resulting in maximum hardness. In the time-based experiments, an increase in duration led to a reduction in retained austenite in the microstructure and an increase in hardness. From a corrosion resistance perspective, samples with higher hardness exhibited lower corrosion resistance; however, with increasing duration, corrosion resistance improved due to the activation of diffusion mechanisms.Yesilyayla Cutting Tools Metal Goods and Construction Industry and Trade Co. Ltd.
AR-GE-20-02