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Nuclear topsy turvy: the security-economics nexus in Turkish-American relations
No full text<p>This article discusses the shift in Turkey's nuclear alliance with the United States from client to junior partner. Ankara sought to bring the Turkish economy and military forces in line with those of its patron to signal its loyalty. But power asymmetries made it so that Washington became Ankara's lifeline. From the 1950s until the mid-1960s, American policymakers applied a top-down style of alliance management, making important decisions without consulting Ankara. But the mid-1960s marked a turning point in the nature of this relationship, as Turkey became better able to stand on its own feet. Rather than relying on unilateral measures, the Americans had to consult and coordinate with Ankara. Also, Turkey could reject key American proposals involving nuclear weapons, such as the creation of a Multilateral Force for NATO, and even create some ambiguity about its nuclear intentions to signal its loss of faith in the American security guarantee.</p>
Acute treadmill exercise induces mitochondrial unfolded protein response in skeletal muscle of male rats
No full text<p>Mitochondria are often referred to as the energy centers of the cell and are recognized as key players in signal transduction, sensing, and responding to internal and external stimuli. Under stress conditions, the mitochondrial unfolded protein response (UPRmt), a conserved mitochondrial quality control mechanism, is activated to maintain mitochondrial and cellular homeostasis. As a physiological stimulus, exercise-induced mitochondrial perturbations trigger UPRmt, coordinating mitochondria-to-nucleus communication and initiating a transcriptional program to restore mitochondrial function. The aim of this study was to evaluate the UPRmt signaling response to acute exercise in skeletal muscle. Male rats were subjected to acute treadmill exercise at 25 m/min for 60 min on a 0 % grade. Plantaris muscles were collected from both sedentary and exercise groups at various times: immediately (0), and at 1, 3, 6, 12, and 24 h post-exercise. Reactive oxygen species (ROS) production was assessed using hydrogen peroxide assay and dihydroethidium staining. Additionally, the mRNA and protein expression of UPRmt markers were measured using ELISA and real-time PCR. Mitochondrial activity was assessed using succinate dehydrogenase (SDH) and cytochrome c oxidase (COX) staining. Our results demonstrated that acute exercise increased ROS production and upregulated UPRmt markers at both gene and protein levels. Moreover, skeletal muscle exhibited an increase in mitochondrial activity in response to exercise, as indicated by SDH and COX staining. These findings suggest that acute treadmill exercise is sufficient to induce ROS production, activate UPRmt signaling, and enhance mitochondrial activity in skeletal muscle, expanding our understanding of mitochondrial adaptations to exercise.</p>
Robust Prescribed Time Control of Euler–Lagrange Systems
No full text<p>This article aims to develop a robust prescribed time controller for precise trajectory tracking for uncertain Euler-Lagrange systems with unknown time-varying disturbances without prior knowledge of their upper bounds. The control strategy involves utilizing a scaled transformation function to map the standard error system to a scaled error system. The presented controller is developed based on the scaled error system, incorporating state-dependent control gains and yielding a model-free controller structure. Distinguishing from previous methods, the designed controller takes a different approach by avoiding the direct multiplication of feedback terms with the estimated inertia matrix. The developed strategy mitigates the adverse effects of mismatches between the actual and estimated inertia matrices. A novel Lyapunov-based stability analysis is employed to establish fixed-time input-to-state stability within the prescribed time and to ensure the convergence of error signals to the origin. Experimental validation on a three-degree-of-freedom planar robot arm confirms the effectiveness of the proposed controller.</p>
FDA-approved disulfiram induces ferroptosis via alteration of redox balance and lipid peroxidation and overcomes carfilzomib resistance in multiple myeloma
No full text<p>Multiple myeloma (MM), a malignant plasma cell disorder, remains incurable due to inevitable chemo-resistance development, including carfilzomib (CFZ) leading to relapse and poor patient outcomes. Therefore, new treatment strategies, including using FDA-approved alcohol deterrent disulfiram (DSF) are under investigation. The present study investigated the effect of DSF on ferroptosis and CFZ resistance in MM cells. Our findings indicate that DSF increases the production of cytosolic and mitochondrial reactive oxygen species, and causes a loss of mitochondrial Delta psi and an elevation in lipid peroxidation in MM cells. DSF treatment in MM cell lines led to the significant downregulation of ferroptotic genes, including glutathione peroxidase 4. Moreover, ferroptosis inhibitor liproxstatin-1rescued DSF-induced ferroptosis by promoting glutathione peroxidase 4 upregulation. DSF alone overcomes CFZ resistance through lipid peroxidation elevation and acts synergistically with CFZ in CFZ-resistant MM cell lines. Our results suggest that DSF is a promising anti-myeloma agent for overcoming CFZ resistance in MM through ferroptosisinduction.</p>
Preharvest 1-methylcyclopropene and aminoethoxyvinylglycine treatment effects on 'NY2' (RubyFrost®) apple fruit quality and postharvest watercore dissipation at different temperatures
No full text<p>Recent studies have found that dissipation of watercore in apple fruit after harvest can be enhanced by preharvest application of 1-methylcyclopropene (1-MCP). In this study, the effects of plant growth regulators (PGRs) on watercore dissipation have been extended to the use of aminoethoxyvinylglycine (AVG) and the effects of storage at 3 degrees C, 10 degrees C, and 20 degrees C over 30 d. Preharvest 1-methylcyclopropene (1-MCP) and aminoethoxyvinylglycine (AVG) treatments were applied one week before harvest to 'NY2' (RubyFrost (R)), a cultivar that is prone to development of a stress-associated type of watercore during fruit maturation. Fruit were harvested twice (H1 and H2), 11 d apart. 1-MCP and AVG treatments had more pronounced effects on maturity at H2, with higher IAD values and flesh firmness, respectively, compared with those of fruit harvested at H1. During storage, 1-MCP and AVG treated fruit had lower ethylene production and respiration rates than untreated fruit at H1, but ethylene production in 1-MCP treated fruit increased on day 17 at H2, reaching levels similar to untreated fruit, while remaining low in AVG-treated fruit. IECs were lower in fruit stored at 3 degrees C than at 10 degrees C or 20 C. Both treatments maintained low IECs, but more persistently in AVG-treated fruit. Flesh firmness and titratable acidity were higher, and greasiness was lower, in AVG and 1-MCP treated fruit compared with untreated fruit. The PGR treatments had no effect on watercore incidence at H1 as incidence was low in all treated fruit. At H2, 1MCP reduced watercore incidence at harvest compared with untreated and AVG-treated fruit, which had similar incidences. Watercore dissipation was enhanced by AVG, being more rapid with higher storage temperature. The mechanism by which PGRs can increase watercore dissipation is unknown, but they might alter sorbitol transporter activity and/or cell membrane stability for sorbitol uptake from the intercellular space into the parenchyma cells. Nevertheless, the use of PGRs may be a useful way to decrease the incidences of flesh browning disorders associated with high watercore incidence in fruit at the time of harvest.</p>
Genome mining of <i>Bacillus thuringiensis</i> strain SY49.1 reveals novel candidate pesticidal and bioactive compounds
No full text<p>BACKGROUND: Bacillus thuringiensis SY49.1 (Bt SY49.1) strain has promising insecticidal and fungicidal activity against phytopathogens and pests. Therefore, we selected this strain for whole-genome sequencing (WGS), annotation and analysis, with the aim of identifying genes responsible for producing putative pesticidal toxins, antimicrobial metabolites and plant growth-promoting features. RESULTS: Our results showed that the SY49.1 genome is 6. 32 Mbp long with a GC content of 34.68%. Genome mining revealed the presence of multiple gene inventories for the biosynthesis of bioactive compounds such as insecticidal delta endotoxins, secondary metabolites, and several plant growth-promoting proteins. Multiple sequence alignment revealed residue variations in the toxic core of Cry1Ab when compared with known Cry1Ab sequences from Bt nomenclature databases. This suggests that the cry1Ab of SY49.1 is a new kind of its group. Among the predicted secondary metabolites, we found a kurstakin with a predicted peptide that differs from the known kurstakin peptide available in the NORINE database. In addition, lipopeptides extracted from SY49.1 suppressed the growth of Verticillium dahliae and Fusarium oxysporum. CONCLUSION: We anticipate that the complete genome of Bt SY49.1 may provide a model for properly understanding and studying antimicrobial compound mining, genetic diversity among the B. cereus group, and pathogenicity against insects. This is the first report on the WGS and mining of the Bt strain isolated from Turkey. (c) 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.</p>
Synthesis, characterization, and theoretical study of new cocrystals and charge-transfer compounds
No full text<p>This study used single-crystal X-ray diffraction, elemental analysis, infrared (IR) spectroscopy, theoretical nuclear magnetic resonance (NMR), and theoretical ultraviolet spectroscopy to characterize 3 newly synthesized crystalline compounds. Additionally, the nonlinear optical, highest occupied molecular orbital energies, lowest occupied molecular orbital energies, band gap, molecular electrostatic potential, and thermodynamic parameters of the 3 crystalline compounds were examined. The strong correlation between experimental IR spectra and theoretical NMR chemical shifts confirmed the accuracy of computational predictions. The molecular formulas of the 3 newly synthesized crystalline compounds, each containing different ligand molecules, were: C<sub>8</sub>H<sub>14</sub>O<sub>4</sub>·2(C<sub>6</sub>H<sub>4</sub>N<sub>2</sub>), C<sub>5</sub>H<sub>7</sub>N<sub>2</sub>·NCS, and Ni(CN)<sub>4</sub>·2(C<sub>5</sub>H<sub>7</sub>N<sub>2</sub>)·2(H<sub>2</sub>O) for compounds 1, 2, and 3, respectively. Crystallographic analysis showed that the compounds crystallize in the space groups <em>P</em> , <em>P</em>2<sub>1</sub>/<em>n</em> and <em>C</em>2/<em>m</em>, respectively. Their molecular packing is stabilized by a network of hydrogen bonds (C–H∙∙∙O, O–H∙∙∙N, N–H∙∙∙N, N–H∙∙∙S, O–H∙∙∙N, and N–H∙∙∙O) and noncovalent interactions (C–H∙∙∙π and π∙∙∙π). Computational studies using Gaussian 03 and CrystalExplorer further elucidated their structural, magnetic, electrooptic, and electrochemical properties.</p>
High-frequency asymptotic expansions for multiple scattering problems with Neumann boundary conditions ☆
No full text<p>We consider the two-dimensional high-frequency plane wave scattering problem in the exterior of a finite collection of disjoint, compact, smooth (C infinity), strictly convex obstacles with Neumann boundary conditions. Using integral equation formulations, we determine the H & ouml;rmander classes and derive Melrose-Taylor type high-frequency asymptotic expansions of the total fields corresponding to multiple scattering iterations on the boundaries of the scattering obstacles. These asymptotic expansions are used to obtain sharp wavenumber dependent estimates on the derivatives of multiple scattering total fields. Numerical experiments supporting the validity of these expansions are presented. (c) 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.</p>
Design, fabrication, and experimental validation of a new microwave-assisted distiller for the large-scale industrial systems
No full text<p>It is crucial to distill essential oils, especially from medicinal and aromatic plants, in high yield without losing their chemical properties. Within the scope of this study, big enough in contrast to microwave-assisted distillers (MWAD) used in the laboratory, an industrial-scale microwave-assisted distillation system is designed and fabricated. There are 12 magnetrons, each with a power of 1 kW operating at 2.45 GHz. Different magnetrons' operating time duration and working order compositions have been optimized and tabulated in comparison for efficiency. Throughout the study, using the proposed system, a max 24 % improvement in essential oil yield, a 50 % improvement in working time (from 90 min to 45 min), and a max 25 % improvement in energy saving is achieved compared to conventional steam distillation (CSD). The proposed system can be an alternative to different inefficiencies experienced in industrial-scale traditional distillation of steam systems.</p>
Tumor-specific cytotoxicity of pyrazole-based chalcone derivatives in human oral squamous cell carcinoma cell lines
No full text<p><strong>Background:</strong> Pyrazole-based chalcone hybrids are notable in medicinal chemistry for their potential biological activity. Their tumor-specific cytotoxicity and mechanisms remain unknown in OSCC cells. This is the first study of pyrazole–chalcone hybrids in OSCC cells. This study explores the tumor-selective cytotoxic effects and the underlying cell death mechanisms triggered by a series of ten newly synthesized pyrazole-based compounds (<strong>MS1–MS10</strong>) in OSCC cell lines.</p>
<p><strong>Material and methods:</strong> The cytotoxic effects of the compounds were assessed using the MTT assay on four human OSCC cell lines and three types of normal human oral cells. Tumor-selectivity index (TS) and Potency-selectivity expression (PSE) were calculated. Active compounds were subjected to cell cycle analysis. For QSAR modeling, 3,096 descriptors comprising physicochemical, structural, and quantum chemical features were created using the most energetically advantageous conformations found from CORINA optimization.</p>
<p><strong>Results:</strong> According to the results obtained, the compounds <strong>MS4</strong> (PSE= 1443.6, TS= 71.2), <strong>MS7</strong> (PSE= >15304.5, TS= >247.4), and <strong>MS8</strong> (PSE= >7141.4, TS= >169.0) showed the highest TS and PSE values, comparable with doxorubicin and 5-FU. The cytotoxic compounds <strong>MS7</strong> and <strong>MS8</strong>, as well as the cytostatic compound <strong>MS4</strong>, significantly (<em>p</em><0.05) increased the cell population in the S and G2/M phases while decreasing the population in the G1 phase. Importantly, no significant accumulation was detected in the sub-G1 phase, which specifically indicates the absence of DNA fragmentation–associated apoptosis. QSAR analysis suggests the importance of 3D structure and lipophilicity in TS expression. ADMET analysis further revealed the drug-likeness properties of the active compounds, and the information obtained is expected to contribute significantly to the literature on the design and development of new compounds.</p>
<p><strong>Conclusion:</strong> This study demonstrates the potent tumor-specific cytotoxic and cytostatic effects of pyrazole-based chalcone hybrids on OSCC cell lines, offering valuable insights for targeted anticancer drug development.</p>
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