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A review of the potential involvement of small RNAs in transgenerational abiotic stress memory in plants
Get PDFCrop production is increasingly threatened by the escalating weather events and rising temperatures associated with global climate change. Plants have evolved adaptive mechanisms, including stress memory, to cope with abiotic stresses such as heat, drought, and salinity. Stress memory involves priming, where plants remember prior stress exposures, providing enhanced responses to subsequent stress events. Stress memory can manifest as somatic, intergenerational, or transgenerational memory, persisting for different durations. The chromatin, a central regulator of gene expression, undergoes modifications like DNA acetylation, methylation, and histone variations in response to abiotic stress. Histone modifications, such as H3K4me3 and acetylation, play crucial roles in regulating gene expression. Abiotic stresses like drought and salinity are significant challenges to crop production, leading to yield reductions. Plant responses to stress involve strategies like escape, avoidance, and tolerance, each influencing growth stages differently. Soil salinity affects plant growth by disrupting water potential, causing ion toxicity, and inhibiting nutrient uptake. Understanding plant responses to these stresses requires insights into histone-mediated modifications, chromatin remodeling, and the role of small RNAs in stress memory. Histone-mediated modifications, including acetylation and methylation, contribute to epigenetic stress memory, influencing plant adaptation to environmental stressors. Chromatin remodeling play a crucial role in abiotic stress responses, affecting the expression of stress-related genes. Small RNAs; miRNAs and siRNAs, participate in stress memory pathways by guiding DNA methylation and histone modifications. The interplay of these epigenetic mechanisms helps plants adapt to recurring stress events and enhance their resilience. In conclusion, unraveling the epigenetic mechanisms in plant responses to abiotic stresses provides valuable insights for developing resilient agricultural techniques. Understanding how plants utilize stress memory, histone modifications, chromatin remodeling, and small RNAs is crucial for designing strategies to mitigate the impact of climate change on crop production and global food security
The relationship between stock prices and financial failure: The case of manufacturing companies in the Borsa Istanbul-30 index
Get PDFSosyal Bilimler Enstitüsü, Bankacılık ve Finans Ana Bilim DalıBir şirketin finansal başarısızlığı, şirketin finansal yükümlülüklerini zamanında ödeyememe olasılığıdır. Finansal başarısızlık, şirketin iflası, yeniden yapılanması veya başka bir şekilde tasfiyesi ile sonuçlanabilir. Finansal başarısızlık riski, bir şirketin hisse senedi fiyatını etkileyebilecek önemli bir faktördür. Finansal başarısızlığı yüksek olan bir şirket, yatırımcılar tarafından daha riskli olarak algılanır ve bu da hisse senedi fiyatının düşmesine neden olabilir. Bu çalışmada, Borsa İstanbul-30 imalat sektöründe listelenen şirketlerin hisse senedi fiyatları ile finansal başarısızlıkları arasındaki ilişki incelenmiştir. Çalışma, 2010-2020 dönemi için BİST-30'da yer alan 11 şirketlik bir örneklem üzerinde yürütülmüştür. Çalışmanın bulgularına göre, finansal başarısızlık riski ile hisse senedi fiyatları arasında uzun dönemli bir ilişki bulunmaktadır. Söz konusu durum finansal başarısızlık ile hisse fiyatlarının etkileşiminin kısa dönemde değil de uzun dönemde oluştuğunu göstermektedir. Çalışmanın bulguları, yatırımcılar için önemli bir ipucu sunmaktadır. Genellikle yatırımcılar bilanço sonuçlarını kısa dönemde fiyatlamaktadır. Çalışma sonuçlarına göre finansal başarısızlık durumu anında ortaya çıkan bir durum değildir. Hisse fiyatları üzerinde uzun dönemde bir etkileşim meydana getirmektedir. Finansal başarısızlığı daha yüksek olan şirketlerin hisse senetlerine yatırım yapmadan önce, bu şirketlerin finansal durumlarını dikkatlice değerlendirmeleri gerekmektedir.The financial failure of a company refers to the probability that the company may not meet its financial obligations on time. Financial failure can result in the company's bankruptcy, restructuring, or liquidation. The risk of financial failure is a significant factor that can impact a company's stock price. A company with a high risk of financial failure is perceived as riskier by investors, potentially leading to a decline in its stock price. In this study, the relationship between stock prices and financial failures of companies listed in the Borsa Istanbul-30 manufacturing sector has been examined. The study was conducted on a sample of 11 companies listed in the BIST-30 for the period 2010-2020. According to the findings of the study, there is a long-term relationship between the risk of financial failure and stock prices. This indicates that the interaction between financial failure and stock prices occurs not in the short term but rather over the long term. The findings of the study provide a crucial insight for investors. Typically, investors tend to price balance sheets in the short term. However, according to the study results, the situation of financial failure is not an instantly emerging condition. It exerts an influence on stock prices in the long term. Before investing in stocks of companies with higher financial failure risk, investors should carefully evaluate the financial conditions of these companies
Self-Healing Performance of Nanosilica-Modified Engineered Cementitious Composites Exposed to High Temperatures
Get PDFThis study investigated the self-healing performance of nanosilica-modified engineered cementitious composites (ECCs) exposed to high temperatures. Nanosilica (NS) was used in 0%, 0.25%, 0.50%, and 0.75% proportions of cementitious materials by mass in the mixtures. NS-modified ECC cylindrical samples (o100x200 mm) were produced and cured at 23 degrees C +/- 2 degrees C for 28 days. Then, these samples were exposed to 20 degrees C +/- 2 degrees C, 100 degrees C, 200 degrees C, 300 degrees C, 400 degrees C, 500 degrees C, 600 degrees C, 700 degrees C, and 800 degrees C temperatures. After the samples were cooled at room temperature, microcracks were formed in the ECC samples, but the samples exposed to higher than 400 degrees C were dispersed when the crack was formed. The wetting-drying cycles were applied for the self-healing of cracked samples. Lastly, the splitting tensile strength, ultrasonic pulse velocity, and chloride ion permeability of the NS-modified ECC samples were determined. Scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX), X-ray diffraction analysis (XRD), and Fourier transform infrared spectroscopy (FTIR) analyses were also performed to examine the microstructure of NS-modified ECC samples. This study found that all samples were self-healed within 15 days, and the highest splitting tensile strength recovery rate was obtained from 0.75 NS-modified ECC samples with 107.44%
Selective separation and determination strategy for monitoring E100, E127, E129 and E133 in foodstuffs: Vortex assisted sequential-simultaneous liquid phase micro-extraction
Get PDFA green, speedy and handy, vortex assisted sequential-simultaneous liquid phase micro-extraction procedure (VA-SS-LPME) was established first time without using any instrumental chromatographic techniques for sepa-ration, preconcentration and spectrophotometric determination of four important popularly and widely used food colorants, namely curcumin (E100), erythrosine (E127), allura red (E129) and brilliant blue (E133). Here, n-nonanol and n-nonanol based deep eutectic solvent were used as extraction solvents. The procedure has included two simultaneous and sequential separation steps by different extractants and two simultaneous UV-vis spectrophotometric determination steps. First, simultaneous separation of E100 and E127 from aqueous solution containing E129 and E133 was achieved and then simultaneous separation of E129 and E133 from aqueous solutions was applied and simultaneous spectrophotometric determinations were performed finally for binary mixture dyes (E100 and E127) and (E129 and E133). The parameters including pH, types and amounts of extractants, vortex time and rate, centrifugation time and rate were investigated in detail for sequential two steps separation and quantitative simultaneous extraction of the dyes. Interference effect of matrix ions, target and other dyes were examined. Possible envisaged extraction mechanisms were elucidated. Green analytical pro-cedure index (GAPI) and analytical eco-scale (AES) parameters of the procedure were determined. As last, E100, E127, E129 and E133 contents of some foodstuffs and pharmaceuticals such as confectioneries, beverages, drugs and syrups were determined by applying optimized procedure. Colourful food additive concentrations of real samples were determined between 2.9 and 93.8 mu g/g and 5.3-112.4 mu g/mL for solid and liquid samples, respectively
Efficacy of volatile organic compounds by Aureobasidium pullulans immobilized on hydrogel spheres against strawberry fungal pathogens
Get PDFBACKGROUND: The present study explores the use of two different growth supports for the biocontrol yeasts Aureobasidium pullulans M13, C10, R34 and P17, by use of nutrient yeast glucose (NYDA) agar and hydrogel spheres as the support matrix, then evaluates their impact on the production of volatile compounds (VOCs) and the subsequent in vitro and in vivo antagonistic activity against Botrytis cinerea and Colletotrichum acutatum. RESULTS: For the in vitro assay, VOCs secreted by the isolates C10 and M13 encased in the hydrogel spheres showed greater inhibitory activity on the mycelial growth of B. cinerea (70.30%) and C. acutatum (52.35%), respectively, with respect to NYDA. For solid-phase microextraction-gas chromatography-mass spectrometry, VOCs produced by the selected yeasts immobilized in the hydrogel spheres or cultured in the agar were identified. VOCs were grouped as alcohols, ketones, alkane and aldehyde, with phenylethyl alcohol and 1-propanol-2-methyl being the most prominently produced. The analysis revealed variations in both quantity and composition of VOCs among the growth supports, indicating the hydrogel spheres as enhancer distinct metabolic pathways and substrate utilization of the isolates, particularly in the M13 isolate. CONCLUSION: The antifungal activity of the VOCs produced in the hydrogel spheres by the isolates C10 and M13 was assessed on strawberries, demonstrating a significant reduction in disease incidences. (c) 2024 Society of Chemical Industry
Pulsed Electric Fields (PEF) Treatment Prior to Hot-Air and Microwave Drying of Yellow- and Purple-Fleshed Potatoes
Get PDFThis study investigated the impact of pulsed electric fields (PEF) treatment combined with hot-air (HA) and microwave (MW) drying on the quality attributes of yellow and purple potato samples. PEF + HA and PEF + MW treatments showed no significant difference in total phenolic content for yellow potatoes. However, the raw purple sample exhibited significantly higher phenolic content compared to purple PEF1 and PEF3 samples. DPPH antioxidant activity for yellow and purple potatoes ranged from 18.48 to 33.19% with HA drying, and from 21.38 to 39.94% with MW drying. MW drying following PEF treatment was more effective in enhancing antioxidant activity compared to HA drying. However, it was observed that PEF levels had no statistical effect on total monomeric anthocyanin. PEF treatment prior to drying may be recommended in practice as it does not cause structural changes in SEM analysis. According to FTIR results, PEF and drying processes caused some changes in the chemical structure of potato samples. In the PCA results, the untreated purple HA sample exhibited characteristics that were most similar to those of the raw purple potato sample. Conversely, the yellow PEF + MW and untreated yellow with MW samples displayed properties closest to the raw yellow potato samples. According to chemometric analysis, the models exhibit high rCV and rPre values coupled with low RMSEC and RMSEP values and negligible disparities between them, indicating strong correlations between the predicted and reference values.Scientific and Technological Research Council of Turkiye (TUBITAK)Open access funding provided by the Scientific and Technological Research Council of Turkiye (TUBITAK
A New Perspective on the Effectiveness of FDG PET/CT in Predicting KRAS Mutation in Colon Cancer Cases
Get PDFAim: The main aim of this study was to evaluate the effectiveness of 18F-fluorodeoxyglucose (18FDG) positron emission tomography/computerized tomography (PET/CT) parameters in predicting the Kristen rat sarcoma viral oncogene(KRAS) mutation status of patients with colon cancer.Materials and Methods: Between April 2013 and December 2020, 79 patients who were diagnosed with colon cancer by colonoscopy underwent staging 18FDG PET/CT with this diagnosis and met all the inclusion criteria were included in this study. Clinical and prognostic features and also imaging (18FDG PET/CT and magnetic resonance imaging) reports of the patients were collected and analyzed retrospectively.Results: KRAS mutation was seen in 32 of patients (40.5%). No significant difference was observed between KRAS mutant and wild-type patients in terms of clinical features (tumor location, findings regarding metastasis, T stage, and tumor differentiation grade in patients who underwent surgery) and overall survival. Progression-free survival was significantly shorter in KRAS mutant patients (p = 0.018). Primary tumor standardized uptake value (SUVmean) was significantly higher in KRAS mutant cases in the whole group (p = 0.024) and in patients in whom KRAS analysis was performed only in the primary lesion (p = 0.036). The cutoff value for predicting KRAS mutation status was 7.01 g/mL (area under the curve [AUC]: 0.650, confidence interval [CI] 95%, 0.56-0.74).Conclusions: When colon and rectal cancer cases were evaluated separately, the primary tumor SUVmean value was significantly higher in KRAS mutant colon cancer cases. However, its effectiveness in predicting KRAS mutation status was low, similar to other parameters in the literature
European endemic Ptychostomum minii (Bryaceae, Bryophyta) - new to Turkey and its significant range extention to SW Asia
Get PDFIn this study, Ptychostomum minii , a European endemic species is recorded for the first time in Turkey and Southwest Asia. The species was found in the Bolkar Mountains in Turkey. Insights into recent discoveries, along with accompanying photographs, ecology, and location specifics in Turkey are presented.Scientific and Technological Research Council of Turkey (TUBITAK) [222Z015]This study was financially supported by the Scientific and Technological Research Council of Turkey (TUBITAK) (Project Code: 222Z015) . We would like to thank for them for their financial support. We also extend special thanks to Prof. Dr. Cecilia Sergio, who confirmed that the Turkish specimen corresponds to Ptychostomum minii
Investigation of the effects of 8 weeks of calisthenic exercises applied to swimmers between 8-10 years of age on some physical and physiological parameters
Get PDFSağlık Bilimleri Enstitüsü, Hareket ve Antrenman Bilimleri Ana Bilim Dalı, Hareket ve Antrenman Bilim DalıBu çalışmanın amacı; 8-10 yaşları arasındaki yüzücülere uygulanan 8 haftalık kalistenik egzersizlerin bazı fiziksel ve fizyolojik parametrelere etkisinin incelenmesidir. Yapılan çalışmaya Kayseri Erciyes Alfa Gençlik ve Spor Yüzme Kulübü sporcularından oluşan toplam 20 erkek öğrenci gönüllü olarak katılmıştır. Çalışmada katılımcılar kontrol grubu (KG, (n:10)) ve kalistenik egzersiz grubu (KEG, (n:10)) olmak üzere 2 gruba ayrılmıştır. Katılımcılara ait vücut yağ yüzdesi (VYY) ve Beden kitle indeksi (BKİ) Tanita BC 418 MA Profesyonel monitörlü Segmental vücut analizi cihazıyla, omuz genişliği Kingstar marka 1.5 metre uzunluğundaki mezurayla, sırt-bacak kuvveti Takei (Japonya) marka sırt-bacak dinamometresiyle, dikey sıçrama testi Jump-metre marka cihazıyla, sağ ve sol el-pençe kuvveti Takei marka el dinamometresiyle ve anaerobik kapasiteleri ise Monark Ergomedic 894 E Peak Bike marka cihaz ile ölçülmüştür. Katılımcılar sezon içerisinde antrenörleri tarafından planlanan yüzme branşına yönelik genel antrenman programlarını antrenman günlerinde uygularken kalistenik egzersiz grubunda (KEG) bulunan katılımcılar yüzme antrenmanlarına ek olarak 8 hafta boyunca ve haftada 3 gün olacak şekilde kalistenik egzersiz programları ayrı ayrı uygulanmıştır. Verilerin analizinde IBM SPSS 21 paket programı kullanılmış olup çalışmanın anlamlılık düzeyi P<0,05* olarak belirlenmiştir. Yapılan normallik testi sonuçlarına göre nonparametrik testler tercih edilmiştir. Katılımcıların boy, yaş ve vücut ağırlığı değişkenlerine ilişkin tanımlayıcı istatistik analizleri yapılırken grupların ön test ve son test ölçümleri arasındaki farkın belirlenmesinde Wilcoxon İşaretli sıralar analiz testi yapılmıştır. Sonuç olarak yüzme sporuyla uğraşan çocuklar üzerinde gerçekleştirilen kalistenik egzersiz programının bacak kuvveti, sağ ve sol el kavrama (el-pençe) kuvveti, omuz genişliği, dikey sıçrama ve anaerobik ortalama güç değerleri üzerinde istatistiksel olarak anlamlı bir artış sağladığı; BKİ, VYY ve Sırt kuvvetinde kalistenik egzersizlerin istatistiksel olarak anlamlı bir fark oluşturmadığı sonucu bulunmuştur. Ayrıca anaerobik güç tepe değeri sonuçlarının kontrol grubu lehine çıkarken kalistenik egzersiz uygulanan katılımcılarda anlamlı fark bulunmamıştır. Kısaca çocuklara uygulanan 8 haftalık kalistenik egzersizlerin çocuklarda yukarıda bahsi geçen bazı fiziksel ve fizyolojik özelliklerin gelişimine olumlu etkisi olduğu söylenebilir. Anahtar Sözcükler: Spor Bilimleri, kalistenik, anaerobik, dikey sıçrama, kuvvet, yüzmeThe purpose of this study; The aim is to examine the effects of 8-week calisthenic exercises applied to swimmers aged 8-10 on some physical and physiological parameters. A total of 20 male students from Kayseri Erciyes Alfa Youth and Sports Swimming Club participated in the study voluntarily. In the study, participants were divided into two groups: control group (CG, (n:10)) and calisthenic exercise group (KEG, (n:10)). Body fat percentage (BFY) and Body mass index (BMI) of the participants were measured with Tanita BC 418 MA Segmental body analysis device with professional monitor, shoulder width with Kingstar brand 1.5 meter long tape measure, back-leg strength with Takei (Japan) brand back-leg dynamometer, vertical Jump test was measured with Jump-meter brand device, right and left hand-claw strength was measured with Takei brand hand dynamometer, and anaerobic capacities were measured with Monark Ergomedic 894 E Peak Bike brand device. While the participants applied the general training programs for the swimming branch planned by their coaches during the season on the training days, the participants in the calisthenic exercise group (KEG) applied separate calisthenic exercise programs, 3 days a week, for 8 weeks, in addition to their swimming training. IBM SPSS 21 package program was used to analyze the data and the significance level of the study was determined as P<0.05*. According to the normality test results, nonparametric tests were preferred. While descriptive statistical analyzes were performed on the participants' height, age and body weight variables, Wilcoxon signed-rank analysis test was used to determine the difference between the pre-test and post-test measurements of the groups. As a result, the calisthenic exercise program performed on children engaged in swimming sports provided a statistically significant increase in leg strength, right and left hand grip (hand-claw) strength, shoulder width, vertical jump and anaerobic average power values; It was found that calisthenic exercises did not create a statistically significant difference in BMI, BMI and back strength. In addition, while the anaerobic power peak value results were in favor of the control group, no significant difference was found in the participants who underwent calisthenic exercise. In short, it can be said that 8-week calisthenic exercises applied to children have a positive effect on the development of some of the physical and physiological characteristics mentioned above. Key Words: Sports Sciences, calisthenic, anaerobic, vertical jump, strength, swimmin
Discovering popular and persistent tags from YouTube trending video big dataset
Get PDFYouTube is the most popular video content platform which provides easy and fast accessibility, huge number of videos, qualified and large number of content producers, and wide range of users. Based on these advantages, YouTube datasets have a big data nature in terms of data analytics. Analyzing YouTube big datasets is essential for discovering user-video relations, video recommendation, semantic analysis of video comments and trending videos analysis. However, YouTube big data analysis has several challenges, such as video content issues, textual and semantic challenges, different metadata information about videos, and big data nature of YouTube datasets. In the literature, several studies are performed for sentiment analysis of YouTube video comments, video recommendation methods, and trending video analyses approaches. In this study, a new method is proposed for popular and persistent tags discovery which uses YouTube trending video dataset of United States for the year of 2021. A new algorithm is proposed, named as Popular and Persistent Tag Discovery algorithm (PPTagD algorithm), which uses proposed method. The proposed algorithm is experimentally evaluated on the dataset. The experimental results show the effectiveness of the proposed algorithm on discovering popular and persistent tags. The results reveal the tendency of United States YouTube users in terms of video tag popularity