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The Impact of Female Representation in Top Management on R&D Intensity: Evidence on the Moderating Effect of the COVID-19 Pandemic
No full textClinical characteristics and outcome of fetuses with ventriculomegaly: a retrospective multicenter study
No full textPurpose: To evaluate the incidence of associated structural anomalies, chromosomal/genetic abnormalities, infections and outcomes of fetuses with ventriculomegaly (VM). Methods: Retrospective multicenter cohort study of 627 pregnancies with fetal VM. VM was classified as mild, moderate, or severe and isolated or non‐isolated. Genetic, obstetric and outcome data were collected and compared according to VM categories. Results: The incidences of associated structural anomalies were 21.9%, 53.1% and 63.9% in mild, moderate and severe VM, respectively (p = 0.032 mild vs. moderate-severe). The incidences of genetic abnormality and fetal infection of the total VM group were 16.1% and 0.8%, respectively, with no significant differences between the VM categories (p > 0.05). The incidences of pathogenic genetic variant in the mild, moderate and severe VM were 13.5% (5/37), 16.7% (3/18) and 38.1% (8/21), respectively (p = 0.032 mild vs. severe). Fetal MRI identified additional CNS anomalies in 5.6% of cases. The incidences of surviving babies with neurological morbidities were significantly higher in fetuses with non-isolated VM groups than in isolated VM groups (p < 0.001). Conclusion: The prognosis of fetuses with VM mostly depends on the severity and the associated anomalies. In all types of fetal VMs additional genetic investigations are valuable
Simplified Molecular International Prognostic Index as an eligibility criterion for clinical trials: Analysis of the Turkish Lymphoma Study Group's large B-cell lymphoma cohort
No full textComparative first-line trials in large B-cell lymphoma (LBCL) have mostly failed over the last decade. Failures were commonly attributed to overestimation of the progression risk for the control arms, bringing the precision of the international prognostic index (IPI) into scrutiny. Simplified molecular IPI (smIPI), introduced at American Society of Hematology 2023, was developed to address the shortcomings of IPI. This study investigated smIPI and its potential implications as trial eligibility criteria among a multicentre LBCL cohort of 1439 patients. Patients diagnosed between 2012 and 2024 were included. Data were collected from institutional archives. The primary end-point was risk stratification for progression-free survival (PFS). Kaplan-Meier and Cox regression methods were used for survival analyses. The smIPI reclassified 38.2% and 5.3% of patients to higher and lower risk groups from IPI, respectively. Patients reclassified to higher risk groups by smIPI had an increased risk of progression than the rest of the group (hazard ratio = 1.34, p = 0.003). High-risk groups classified by IPI and smIPI had similar outcomes (3-year PFS 54.9% vs. 56.3%); however, the high-risk group size was expanded by 35.2% when defined by smIPI. The smIPI is easily applicable and more sensitive than IPI in identifying patients under high risk of progression who are ideal candidates to participate in clinical research
Kronik Hastalıklarda Beklenen Stigma ÖlçeğiErgen Formu: Türkçe Geçerlik ve Güvenirlik Çalışması
No full textONKOPLASTİK MEME CERRAHİSİ TEKNİKLERİNİN TEMELLERİ
No full textBreast cancer necessitates a multidisciplinary approach, encompassing specialists from departments of surgery, medical oncology, radiation on-cology, radiology, pathology, nuclear medicine, and genetic counseling, as well as psychological support. Surgeons are an important part of multidisciplinary teams, from diagnosis to surgery and even in advanced stages of breast cancer. Beyond conventional surgical approaches, oncoplastic breast surgery is becoming one of the most important topics that colleagues from every discipline involved in breast diseases need to understand.In the 1980s, the phrase “oncoplastic breast surgery” was first used. Compared to traditional approaches, it aims to enhance the quality of life and aesthetic outcomes, while also reducing the effects of the disease. Everyone now uses the phrase to mean any surgery that tries to keep the breasts looking appealing and improving the quality of life without affecting cancer treatment. Oncoplastic surgery is a method that considers the long-term effects for women, and it should be a key part of the recommended treatment for all women with breast cancer. Breast cancer significantly impacts a woman's sense of integrity. Therefore, it highlights the need to minimize the negative effects of surgery.There are many ways to do oncoplastic breast-conserving surgery, but they usually follow three main paths: first, breast reduction techniques were used to remove tumors from areas of the breast that could be re-moved; then, modified methods were used to allow the removal of any breast segment; second, volume replacement techniques were used, with variations of latissimus dorsi flaps and later with local perforator-based flaps; and third, different methods were used to close breast defects, from basic skin reduction methods to adaptations of cosmetic mastopexies.The colleagues from the European Academy of Senology (EAoS), iBreast Book, and SENATURK (Turkish Academy of Senology) wanted to create a resource to improve oncoplastic breast surgery and training for professionals. In, this book consists of 44 chapters written by experts from various countries, including Brazil and India, and perfectly details all these topics conclusion related to oncoplastic breast surgery. This book aims to be of great help to breast surgeons by covering critical and fundamental information in senology. This resource will also be very useful for other members of multidisciplinary teams, surgical assistants, gynecologists, and plastic and reconstructive surgeons. We want to thank all the chapter authors for their hard work and attention to detail in putting together the topics. We also want to thank them again for sharing their experiences and case studies, which have made this book more valuable and informative in both an educational and visual way. On behalf of the Editorial CommitteeProf. Dr. Nuh Zafer CANTÜRK, FACS, FEBS, FEBS-Breast Kocaeli University, Faculty of Medicine, Department of General Surgery, Kocaeli, Turkey</p
Experimental investigation and theoretical modeling of a dynamic function vehicle tire air control valve
No full textThis study comprehensively investigates the pressure-time characteristics of a dynamic-function tire valve through both experimental and theoretical approaches. Systematic tests conducted on tanks with volumes ranging from 7.5 to 60 L were used to characterize the valve's performance during both filling and discharge processes. Based on the International Organization for Standardization (ISO) 6358 standard, an advanced theoretical model was developed. The main contribution of the study is the development and validation of a single coefficient that simplifies valve modelling by accounting for tank volume effects. Using exponential functions derived from extensive experimental data, a simplified yet highly accurate modelling methodology is proposed. This innovative approach replaces complex multi-parameter models with a single volume-dependent coefficient (k), significantly simplifying calculations while maintaining high accuracy and offering practical solutions for engineering applications. The experimental results align well with the theoretical model. During filling processes, it was observed that the model slightly overestimates the pressure at the initial stage, but overall provides reliable results. Additionally, it was found that the discharge coefficient and sonic conductance values decrease as the tank volume increases, indicating higher efficiency in systems with smaller tanks. The findings offer valuable insights for industrial applications such as Central Tire Inflation Systems (CTIS). Future research may explore the application of this approach to different valve types and systems, potentially contributing to the establishment of a new standard in pneumatic system modelling
Acute cadmium toxicity in the medicinal leech Hirudo verbana Carena, 1820 with a novel biomarker for aquatic risk assessment
No full textCadmium (Cd) is a common aquatic contaminant that poses significant ecological risks by disrupting organismal functions and ecosystem balance. This study presents the first detailed evaluation of acute Cd toxicity in the medicinal leech Hirudo verbana Carena, 1820, a species of ecological, biomedical, and conservation importance listed under CITES. In a 96-hour semi-static bioassay with graded Cd exposures (0–32 mg/L), we determined an LC50 of 4.02 mg/L and observed a range of concentration-dependent behavioral and pathological responses, including erratic locomotion, excessive mucus secretion, regurgitation, and penis prolapse. We introduced the Body Flexion Ratio (BFR) to quantify morphological responses to Cd-induced neurotoxic stress in leeches. Measured in dead individuals due to mobility challenges in live leeches, BFR reflects current toxic responses rather than predicting Cd toxicity. A positive correlation between BFR values and Cd concentrations suggests its potential applicability as a non-behavioral indicator in field-based ecotoxicological assessments. Concurrently, Cd exposure led to a marked decline in dissolved oxygen levels and increases in conductivity, total dissolved solids, and salinity, further intensifying physiological stress in exposed organisms. These abiotic shifts correlated with the intensity of toxic responses, implying a synergistic impact of chemical and environmental stressors. This study underscores the utility of medicinal leeches as bioindicators in freshwater ecotoxicology and highlights the necessity of integrating biotic responses, including BFR, with water chemistry and ecosystem health indicators for a more comprehensive and robust risk assessment. Given the dual pressures of habitat degradation and commercial harvesting, urgent conservation measures are warranted. Our findings contribute essential toxicity thresholds and highlight H. verbana as a model for studying sublethal pollutant effects in shallow freshwater ecosystems.</p
In vitro and in vivo evaluation of rectal delivery of novel sulfasalazine-loaded hydrogels and nanofibers for enhanced ulcerative colitis therapy
No full textUlcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) that mainly affects the colon and causes symptoms such as hematochezia, rectal urgency, tenesmus, and abdominal pain. UC has a multifactorial pathogenesis, characterized by a complex interplay of genetic predisposition, environmental factors, and alteration in the gut microbiota. Traditional oral therapy, such as sulfasalazine (SSZ), is usually associated with systemic side effects and poor bioavailability. In response, the current study formulated and compared two rectally administered drug delivery systems, SSZ-loaded hydrogel (SSZIH) and SSZ-loaded nanofiber (SSZNF). Comprehensive characterization using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC) demonstrated the integrity of composition, stability at body temperature, and the successful incorporation of all formulation ingredients into the drug delivery systems. Biocompatibility was also evaluated using an in vitro cytotoxicity assay. Moreover, in vivo test findings, assessed in a chemically induced colitis rat model showed that these formulations dramatically lowered oxidative stress indicators including malondialdehyde (MDA) and myeloperoxidase (MPO), and enhanced antioxidant enzyme activities glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT)). These results suggest that SSZ delivery through a hydrogel and nanofiber system by the rectal pathway can be a more efficient and safer treatment for UC
Major Threat in Textile Wastewaters: Tackling Microplastic Pollution with Electrocoagulation Optimized Using Box-Behnken
No full textThe textile industry wastewater threatens receiving environments due to its high levels of microplastics (MPs) generated from production processes. This study, to our knowledge, is the first to investigate the optimization of MPs removal from textile industry wastewater using electrocoagulation (EC) by a Box-Behnken Design (BBD). MPs of fiber type, specifically PP type, have been detected in this wastewater at an average number of 105 ± 5 MPs/L. In the EC process using aluminum electrodes, BBD was employed to determine the effects of independent process variables (pH, current density, and time) on microplastic (MP) removal and for process optimization. According to the ANOVA results, the quadratic model created for MP removal and all independent variables were statistically significant (p < 0.05). The optimization results indicated that the optimal conditions for MP removal were pH 7.38, current density 54.16 A/m2, and time 14.96 min, resulting in an optimum MP removal efficiency of 98.10%. Validation experiments conducted under these optimal conditions achieved MP removal efficiency of 98 ± 0.23%, confirming the model’s accuracy. Additionally, the operating cost of the EC process under optimum conditions was calculated to be $0.312/m3. According to the Pareto analysis results, pH was found to be the most effective independent variable in MP removal. This study demonstrates that the MP pollution from the textile industry can be effectively removed with high efficiency and low cost using the EC process
Use of İzmit Gulf bottom sludge as a raw material component: eco-friendly wall tile glaze composition
No full textAbstract This study investigates the reuse of İzmit Gulf bottom sludge as a silica substitute in black opaque wall tile glazes. The sludge, containing 44.64 wt% SiO₂ and 7.47 wt% Fe₂O₃, was incorporated at 25–100 wt% replacement rates. Viscosity measurements showed that higher sludge levels significantly increased viscosity from 460 to 920 mPa·s. Thermal analyses revealed that sintering and softening temperatures rose from 734 °C to 798 °C (STD) to 798 °C and 832 °C (S4), demonstrating improved refractory behavior. Microhardness values peaked at ~ 720 Hv in the S1 composition (25 wt% sludge), exceeding both the reference glaze (~ 650 Hv) and higher sludge samples, which showed reduced hardness due to porosity. Gloss decreased progressively from 92 (STD) to 75 (S4), while color parameters remained stable. Leaching tests confirmed that all heavy metals stayed within regulatory limits, although chromium release increased to 0.03 mg/L in S4 but remained below the 0.05 mg/L threshold. Therefore, S1 composition offered the most balanced performance, combining improved hardness, acceptable gloss, and environmental compliance. The findings demonstrate that İzmit Gulf sludge can be valorized as a sustainable glaze raw material when used in controlled proportions, supporting resource conservation and waste minimization in ceramic production.</jats:p