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Genome-wide analysis of miRNAs and their target genes in wheat cultivars with different ploidy levels under drought stress
No full textMain conclusion: This study provides novel insight into the role of miRNAs in the drought resistance of different wheat cultivars, revealing a correlation between ploidy level and drought tolerance. Abstract: MicroRNAs (miRNAs) are endogenous, mostly conserved, non-coding regulatory RNAs with 20–24 nt in length. Although many studies have been conducted on miRNAs that play a role in wheat drought stress response, there are no comparative studies in wheat cultivars with different ploidy levels. Here we compared miRNAs profiles of three wheat cultivars with different chromosome numbers and drought resistance levels using miRNAome and qRT-PCR analysis. Bioinformatics analysis showed that all cultivars shared 93 miRNAs in the control leaf, while 91 miRNAs were shared in stress-treated leaf groups. A total of 90 and 92 miRNAs were expressed by all cultivars in control and stress root samples, respectively. Also, 17 and 21 miRNAs were expressed species-specifically in control and stress leaf, whereas 23 and 20 were expressed in control and stress root groups, respectively. Also, tae-miR159a and tae-miR167c expressions showed drought resistance increases as the ploidy level rises, and Triticum aestivum and Triticum turgidum are more tolerant than Triticum monococcum. Furthermore, according to in silico analysis 729 and 771 genes were targeted in control-leaf and stress-leaf groups of all cultivars; also, 775 and 776 genes were targeted in control-root and stress-root samples by determined miRNAs, respectively. Additionally, degradome data showed 351 and 356 genes were targeted in leaf and root tissues, respectively. These findings propose that genotypic variation is responsible for the differential expression of miRNAs and the target genes in drought stress response. The results could serve as a guide for future research on the drought response mechanism
Electrospun poly (glycerol sebacate) (PGS) membranes for corneal tissue engineering
Get PDFThe demand for corneal tissue replacements increases due to corneal diseases, prompting the exploration of tissue engineering (TE) solutions using biopolymers. Poly (glycerol sebacate) (PGS) is one of the promising biomaterials to be explored in the ocular TE, not only because of its biocompatibility, biodegradability, and elasticity, but also its transparency. However, its low molecular weight and low glass transition temperature (Tg) make PGS scaffold fabrication via electrospinning challenging. Here, we fabricated fibrous membranes by electrospinning of PGS and poly (vinyl alcohol) (PVA) blend and obtained a membrane composed of homogenous fibers with a diameter of 4 µm and a porosity of 28%. In addition, the membrane exhibited a stiffness of 12 MPa and strain of 20%. The permeability of the membrane closely resembled that of the natural cornea with 9.8E-07 cm2/s. Most of the PVA was successfully washed off, resulting in biocompatible scaffold that was able to support the proliferation of human corneal epithelial cells (HCEC) and human corneal endothelial cells (HCEndC) for a week. According to the in vitro biocompatibility assay, HCEC has demonstrated an 88% and HCEndC a 96% viability on electrospun PGS membranes. These results demonstrate the suitability of electrospun PGS membrane for cornea tissue engineering
Zombie firms in network: congestion and evergreening
No full textWe explore the spillover impact of zombie firms in Turkey by exploiting a rich administrative dataset that contains firm-level information on balance sheets, inter-firm sales, employment, and firm-bank level credit records. We document three key facts regarding zombie dynamics: (i) Leveraging matched firm-bank level credit registry data, we highlight the presence of an evergreening motive, leading to a misallocation of credit away from productive firms. At the same time, healthy firms in zombie-dense networks face reduced credit access. (ii) Zombie firms, which are on average less productive than nonzombie firms, impede investment and employment opportunities at healthier firms. Nonzombie firms operating in sectors with a high prevalence of zombie firms experience lower sales, assets, and productivity. (iii) Incorporating B2B sales data structured similarly to firm-level input–output linkages, our study causally establishes that greater upstream or downstream exposure to zombie firms leads to reduced sales, investment, and employment growth compared to firms without zombie connections. Increased exposure to zombie firms significantly reduces markups, value-added, productivity, and EBIT margins due to cascading effects on production technology, shifting it toward lower value-added. Additionally, a higher share of zombies in the upstream sector reduces input costs for firms due to excess production
Advances in membranes and electrocatalysts to optimize proton-exchange membrane fuel cells
Get PDFProton-exchange membrane fuel cells (PEMFCs) have attracted substantial global attention from academia, industry, and policymakers due to their critical role in enabling clean and efficient energy conversion. This momentum is increasingly reflected in real-world applications, including the commercialization of fuel cell vehicles and growing interest in heavy-duty transport solutions. However, PEMFCs still face major barriers to widespread adoption—chief among them are high system costs and limited durability. These challenges largely stem from the membrane electrode assembly (MEA), the functional core of the fuel cell. Accordingly, extensive research efforts have focused on advancing MEA materials, particularly membranes and electrocatalysts, to enhance performance while reducing cost and improving longevity. This review provides a comprehensive overview of recent developments in both state-of-the-art and emerging MEA materials alongside fabrication strategies and their associated trade-offs. By outlining key limitations and proposing future research directions, this work highlights the urgent need for durable, efficient, and scalable solutions to drive PEMFC commercialization in sectors such as transportation, energy storage, and distributed power generation
In silico design of potential HCV NS5B inhibitors: a comprehensive approach combining combinatorial library generation, ensemble docking, MM-GBSA calculations, QSAR model development, and molecular dynamics
No full textHCV is a blood-borne RNA virus that causes acute and chronic hepatitis, cirrhosis, liver failure, and hepatocellular carcinoma. In the present work, a large in silico combinatorial library was generated using the privileged substructures of existing inhibitors of the HCV NS5B protein. Next, we performed a multistep virtual screening process to identify novel HCV NS5B inhibitors. Additionally, we assessed the hit compounds' pharmacokinetic characteristics to evaluate their potential as drugs. Hit molecules with drug-like properties were classified with fingerprint-based chemical similarity clustering. Molecular dynamics simulations confirmed the stability of complexes and provided a comprehensive understanding of the molecular interactions between the novel molecule classes and HCV NS5B polymerase. The results of this study set the stage for developing new scaffolds as allosteric inhibitors of HCV NS5B protein for drug designing objectives and highlight the promising prospects of using privileged substructures for screening library construction in pharmaceutical research
U-Pb calcite geochronology, EPR, geochemistry, and C-O-Sr isotopes of ancient marbles in the İznik Region (Bursa-Türkiye)
No full textThe İznik city (ancient Nicaea), located east of Lake İznik (known as-“Bithynia” in ancient times), has been an important political and cultural centre of Asia Minor since the Hellenistic period. Marbles produced in the quarries in the vicinity (Ömerli and İnikli villages, Deliktaş-Sarıtaş hills) were used both in the construction of the walls and in many ancient works in the city. Approximately eighteen ancient marble quarries producing grey and white marbles were investigated in the region. Petrography, EPR, XRD, C-O-Sr isotope and whole rock geochemistry analyses were performed for characterization of the samples collected from the quarries for the provenance studies. According to the new geochemistry and C-O-Sr isotope data, the limestones forming the marbles were deposited in open sea-ocean environments. U-Pb calcite dating determined that the white marbles were 93.06 ± 8.55 Ma, while the grey marbles were 94.84 ± 1.41 Ma and 88.03 ± 2.13 Ma (Upper Cretaceous: Cenomanian-Coniacian). These ages probably correspond to the crystallization/metamorphism ages of the marbles. The new data set obtained with this study will contribute to the understanding of the geological evolution of the region, and will help researchers to better understand the source region of some white and grey marbles used in ancient buildings
Unveiling the heat shock protein network in sugar beet: comprehensive genome-wide identification, characterization, and stress-induced expression patterns
No full textHeat shock proteins (Hsps) are vital for plant responses to abiotic stress, serving as molecular chaperones that maintain protein stability under adverse conditions. This study supplies a comprehensive genome-wide analysis of Hsp family members in the sugar beet (Beta vulgaris) genome and Hsp family gene expression patterns in three genotypes: drought-tolerant, drought-sensitive, and wild beet (Beta maritima). 334 Hsp genes belonging to six major families (sHsp, Hsp40, Hsp60, Hsp70, Hsp90, and Hsp100) were identified. Abundant tandem and segmental duplication events were observed, particularly within the Hsp70 and Hsp100 families, indicating a potential role in stress adaptation. Gene expression analysis under heat, drought, and combined stress conditions revealed significant upregulation of BvHsp70-22, BvHsp90-03, and BvHsp60-28 in the drought-tolerant genotype, indicating their critical roles in stress recovery. In contrast, the drought-sensitive genotype displayed upregulation of BvHsp60-01 and BvHsp90-03, exhibiting a potentially less robust stress response. BvsHsp-34 and BvsHsp-38 were highly expressed under drought stress in the wild beet, suggesting unique adaptive mechanisms. Synteny and phylogenetic analyses demonstrated conserved genetic linkages between sugar beet Hsp genes and orthologs in Arabidopsis thaliana, Oryza sativa, and Glycine max, indicating evolutionary conservation. Gene ontology analysis highlighted their roles in protein folding, binding, and stress response processes. This research sheds light on the molecular mechanisms behind heat shock protein-driven tolerance to abiotic stress in sugar beet, and identifies BvHsp70-22, BvHsp90-03, and BvHsp60-28 as promising candidate genes for future breeding strategies aimed at enhancing stress resilience
Effect of inherent damping of the series elastic element on rendering performance and passivity of interaction control
No full textWe study a realistic model of series elastic actuation (SEA) under velocity-sourced impedance control (VSIC), where the inherent damping of the series elastic element is considered during the analysis, even when only the elasticity of the series damped elastic element is used to estimate the interaction forces. We establish a fundamental rendering limitation when the viscous damping of the physical filter is considered in the plant model and prove that passive rendering of stiffness levels that are higher than the stiffness of the physical filter, as well as passive rendering of Voigt models whose damping levels exceed the physical damping of the plant, are possible. We introduce passive physical equivalents of the closed-loop SEA systems with inherent series damping while rendering Kelvin-Voigt, spring, and null impedance models to provide an intuitive understanding of the passivity bounds and to enable rigorous comparisons of rendering performance among various closed-loop systems with different plant models (including or omitting the series damping) and/or controllers (utilizing different interaction force estimates). We present a comprehensive set of experiments to verify our results and demonstrate the effect of including/omitting the damping of the physical filter in the model of SEA
Teoman Madra: a pioneer in multimedia art [Teoman Madra: multimedya sanatında bir öncü]
No full textThis article aims to solidify Teoman Madra’s significant position in the history of multimedia art, both within Turkey and internationally, by examining his artistic contributions from the 1960s to the 2000s. The Teoman Madra Archive (TMA), developed through media archaeology and archival studies conducted by Artut in 2020, serves as a primary source of information and inspiration for this study. This archive, composed of visual, audio, and textual materials, has brought to light Madra’s pioneering works and provides valuable insights into his creative process and artistic vision. Multimedia art as an interdisciplinary practice has evolved with shared criteria across various parts of the world. Numerous artists have contributed to this field, creating works that bridge multiple media forms. However, in Turkey’s context, Teoman Madra emerges as a trailblazer whose works hold indispensable historical significance, reflecting the socio-political and cultural dynamics of his time. His innovative approach and contributions have played a critical role in shaping the history of multimedia art in Turkey. This article examines Madra’s life and artistic career, offering analyses and interpretations that highlight his unique contributions and firmly highlight his place in the global history of multimedia art
Spin squeezing enhanced quantum magnetometry with nitrogen-vacancy center qutrits
Get PDFWe explore the utility of quantum spin squeezing in quantum magnetometry, focusing on three-level (qutrit) Nitrogen-Vacancy (NV) centers within diamond, utilizing a standard Ramsey interferometry pulse protocol. Our investigation incorporates the effects of dephasing and relaxation on NV centers’ dynamics during Ramsey measurements, modeled via the Lindblad quantum master equation. We conduct a comparative analysis between the metrological capabilities of a single NV center and a pair of NV centers, considering quantum Fisher information both with and without spin squeezing. The quantum correlations between NV centers are assessed through the evaluation of the Kitagawa-Ueda spin squeezing parameter within a two-level manifold. Additionally, parallel calculations are conducted using a two-level model (qubit) for NV centers. Our findings reveal that leveraging qutrits and spin squeezing yields enhanced magnetometric precision, albeit constrained by dephasing effects. Nevertheless, even in the absence of dynamical decoupling methods to mitigate environmental dissipation, strategic timing of squeezing and free evolution can sustain the advantages of qutrit-based magnetometry