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Objective: Allergic asthma is the most frequently observed subtype of individuals with asthma. The effects of serotonin plays in the pathophysiology of asthma has not been clearly determined. Thus, this study aimed to investigate the association between the 5HTR2C gene rs 6318 G>C polymorphism and allergic asthma in pediatric patients in Cyprus. Methods: This study included total number of 177 individuals with 118 control and 59 pediatric patients (43 atopic and 16 non-atopic asthma patient). A skin prick test was performed for each patient to confirm asthma diagnosis and to evaluate atopic status. Genotyping for the 5HTR2C was completed by Real Time-PCR analysis. Results: The genotype distribution frequencies were not in agreement with the Hardy-Weinberg Equilibrium in the patients’ group (p Discussion & Conclusion: Overall, despite the finding of no association between the 5HTR2C rs6318 C allele and childhood asthma, the current results indicated that there is a strong association between the 5HTR2C rs6318 C variant and childhood atopic asthma.

In a more electrified future, development of high power, compact, and synergistically cooled power electronics for improved performance and reliability is of critical importance to a broad range of defense and commercial applications. As power levels increase, power converters must manage higher thermal loads in smaller and lighter weight packages. This necessitates smarter packaging configurations and more aggressive cooling schemes. This work introduces a novel cooler design for thermal management of high-power switches in a dual active bridge converter: a vertically enhanced manifold microchannel system (VEMMS). As opposed to traditional flat heatsinks, this cooler shrinks in footprint but expands away from the board in the direction of its height ( $z$ -direction), for increased heat transfer area while keeping the footprint on the printed circuit board (PCB) at minimum. Since most power converters’ total height is dictated by magnetic elements such as the core, expanding the cooler in vertical direction does not reduce packing density, while it significantly enhances its thermal performance. Both liquid and air-cooled versions of the cooler are introduced through case studies, and their advantages are assessed through extensive numerical modeling. Volume based power densities of 20 kW/L for the overall converter and 286 kW/L for one full bridge assembly for a 10-kW power converter were attained.

The aims of this study were to identify the factors affecting survival and disease-free survival (DFS) in invasive breast cancer patients who underwent surgery for breast cancer age 40 or younger. Medical records of 216 women with breast carcinoma at age 40 or younger who underwent surgery at our Institution between October 2005 and May 2017 were retrospectively reviewed. One hundred and eighty eight invasive breast cancer patients that were eligible were categorized according to their clinical and pathological features. Univariate analyses of survival and DFS were performed by the Kaplan-Meier method and the log-rank test. Independent prognostic and predictive factors affecting survival and DFS were assessed by Cox regression proportional hazard method. 10-year survival and DFS were 85 and 74%, respectively. Axillary involvement, pathologic tumor size, HER 2 + subtype and Triple Negative subtype were found to be the prognostic factors that independently affected survival and DFS. The prognosis is worse in patients with axillary involvement, tumors larger than 2 cm, and HER 2+ and Triple Negative subtypes. These adverse prognostic factors should be considered during treatment and follow-up of patients age 40 or younger. © 2022 Ondokuz Mayis Universitesi. All rights reserved. 2-s2.0-85142454724

BACKGROUND: Articular cartilage repair has been a challenge in orthopedic practice due to the limited self-regenerative capability. Optimal treatment method for cartilage defects has not been defined. We investigated the effect of decellularized human placental (DHP) scaffold, mesenchymal stem cells (MSC) and platelet-rich plasma (PRP) on hyaline cartilage regeneration in a rat model. METHODS: An osteochondral defect was created in trochlea region of the femur in all groups, bilaterally. No additional procedure was performed in control group (n = 14). Only the DHP scaffold was applied to the P group (n = 14). The DHP scaffold and 1 × 10(6) MSCs were applied to the PS group (n = 14). The DHP scaffold and PRP were applied to the PP group (n = 14). The DHP scaffold, 1 × 10(6) MSCs and PRP were applied to the PSP group (n = 14). Outcome measures at 12 weeks included Pineda histology score and qualitative histology. RESULTS: The mean Pineda scores of P, PS, PP, and PSP groups were significantly better than the control group (p = 0.031, p = 0.002, p 0.05). CONCLUSION: In conclusion, the DHP scaffold appears to be a promising scaffold on hyaline cartilage regeneration. The augmentation of DHP scaffold with MSCs and PRP combinations did not enhance its efficacy on articular cartilage regeneration.

The high costs and extensive time needed for the treatment of critical-sized bone defects are still major clinical concerns in orthopedic surgery, therefore, researchers continue to look for more cost and time-effective methods. This study aims to investigate the effects of a decellularized omentum scaffold with a combination of platelet-rich plasma (PRP) and mesenchymal stem cells on the healing of critical-sized bone defects. Wistar albino rats (n = 30) were investigated in five groups. Critical-sized bone defects were formed on bilateral radius shafts. No scaffold, decellularized omentum, omentum with PRP and omentum + mesenchymal stem cells was used in group 1 (control group), 2, 3 and 4, respectively. In addition, omentum with a combination of mesenchymal stem cells +PRP was used in group 5. After 6 weeks, both radiological and histological healing were evaluated comparatively among the groups. After the use of a decellularized omentum scaffold, vitality of new cells was maintained, and new bone formation occurred. When compared to the control group, radiological healing was significantly better (p = 0.047) in the omentum and omentum + PRP-treated groups. Furthermore, histological healing was better in the omentum and omentum + PRP-treated groups than the control group (p = 0.001). The use of a decellularized omentum scaffold is suitable in the healing of critical bone defects.

OBJECTIVE We aimed to overview clinical characteristics of FPIAP with the results of diagnostic tools like APT, SPT and fecal calprotectin levels and the factors associated with tolerance development. METHODS All patients diagnosed FPIAP at the outpatient clinic between January 2015 and January 2019 were enrolled retrospectively. Data about clinical characteristics, APT or SPT results, fecal calprotectin levels, suspected triggering foods, diet and tolerance status were obtained from the hospital database program and analyzed. RESULTS 169 infants with F/M ratio 78/91 were enrolled. The mean age of the study population was 3.68 months (1-35 months, mean age 3.68 ± 4.33). APT was performed 137 of the participants and 126 (92%) of them were positive to at least one food allergens, 14 (48.2%) patients had positivity to at least one of the food allergens on SPT. Specific IgE were done in 90 patients and 12 (13.3%) revealed positive results. Two groups of patients developing tolerance before and after 18 months of age were evaluated; mucoid diarrhea, family history allergic diseases, cow's milk sensitivity and multiple allergen triggers were statistically significant risk factors for delayed tolerance according to univariate logistic analysis. However, none of these factors were revealed statistical significance in multivariate logistic analysis. CONCLUSIONS Our study revealed that APT may be a useful tool for programming the elimination diet in breastfeeding mothers. SPT, specific IgE and fecal calprotectin are not necessary for FPIAP management. Multivariate regression analysis showed that none of the evaluated parameters had statistically significant relationship with the tolerance development.

To improve the reliability and efficiency of power electronics, their thermal management must be further enhanced. Next-generation electronics systems are predicted to dissipate more heat as die size shrinks and power levels increase. Traditional air-cooling approaches usually provide insufficient performance or require heavy and bulky heat sinks to achieve adequate thermal management. To address this problem, a novel air cooled vertically enhanced manifold microchannel system (VEMMS) was developed. While minimizing the footprint required on the printed circuit board, the system offers efficient thermal management in a conformal scheme that accommodates the associated power electronics and their electrical connections. This work describes the manufacturing process of the air-cooled VEMMS heat sink and its experimental characterization and thermo-fluidic performance. Good agreement was obtained between the test results and numerical predictions. Using air at ambient conditions, thermal resistance of 2.6 K/W was achieved with a single-sided cooling architecture with a

Introduction In this study we presented our results with anterior component separation technique utilized in the repair of giant ventral hernias. Our primary endpoints were the rates of surgical site occurrences and recurrence at three years. Besides we investigated the impact of components separation repair on abdominal wall functions. Methods We retrospectively analyzed the prospectively-collected data of 40 patients that were operated on between April 2004 and February 2012 for their median ventral hernias sizing larger than 15 cm in width. Our inclusion criteria for component separation program excellently corresponded today's “giant ventral hernia” standards. The method used for components separation was identical to the original Ramirez technique, and did not comprise of any mesh reinforcement. The ICU stays, prolonged intubation, early and late complications, mortality and recurrences at three years were recorded. We used a curl-up test to demonstrate the amelioration of the abdominal wall functions postoperatively. Results The older age and larger defect size were the significant risk factors necessitating prolonged intensive care. Surgical site occurrences were recorded in 18 patients (45.0%). A total of 7 recurrences (17.5%) were detected at three years. Patients showed a significant improvement in raising their trunks after repair (p Conclusions Our findings demonstrated that components separation technique in the original form caused excessive wound complications including skin necrosis which in turn caused delayed discharge from the hospital. The 17.5% recurrence rate seemed higher than those of more recent papers. The already-established newer modifications should be integrated in the repair method. The components separation repair clearly improves abdominal wall functions.

Background: High-cost and the long time needed for the treatment of critical-sized bone defects is still major clinical concern in orthopedic surgery, therefore new research continues to identify more cost and time-effective methods. In this study, we aimed to investigate the effect of a decellularized omentum scaffold with a combination of platelet-rich plasma (PRP) and mesenchymal stem cells on the healing of critical- sized bone defects. Materlials and methods: Wistar albino rats (n­=30) were investigated in five groups. Critical-sized bone defects were formed on bilateral radius shafts. To increase healing, no scaffold, decellularized omentum, omentum with with PRP and omentum mesenchymal stem cells was used in group 1 (control group) , 2, 3 and 4 respectively. In addition omentum with a combination of mesenchymal stem cells and PRP was used in group 5. After 6 weeks, both radiological and histological healing were evaluated comparatively among groups. Results: After use of decellularized omentum scaffold, vitality of new cells maintained, new bone formation occurred. When compared to control group, radiological healing was statistically significantly better in omentum and omentum with PRP-treated groups (p=0.047). Furthermore histological healing was better in the omentum and omentum with PRP-treated groups than both control and omentum with mesenchymal stem cell-treated groups according to Salkeld Scoring System (p=0.001).Conclusion: The use of decellularized omentum scaffold is suitable in the healing of critical bone defects.

There are strong incentives to reduce the size of advanced power electronics, such as high-frequency converters. Reduced system size often lowers parasitic losses, system weight, and system cost. Two items significantly limiting such reductions in size, however, are the following: 1) the dimension of magnetic devices such as transformers; and 2) the size of the cooling system, including heat sinks, required to dissipate the heat generated in the transformer windings. This paper will present an advanced transformer configuration that allows for significant volume reduction by using additive manufacturing (AM) to deposit planar transformer windings on a thermally conductive combined-core-and-coil (C3) cooler substrate. The candidate material of the C3 cooler is ceramic, as it needs to be electrically insulating but thermally conductive. The C3 cooler is additively manufactured using selective laser sintering (SLS) technology, so as to have channels for liquid cooling inside. Windings are deposited on this cooler substrate by syringe printing and sintering of nano-silver (nano-Ag) and other conductive pastes, making the design flexible and sustainable. These planar transformer windings spiral with 45° angles between each straight segment. A minimum spacing of 0.45 mm between the windings has been achieved without shorting. This paper will also detail the effect of the sintering process times and temperatures on electrical resistivity and adhesive bonding strength. Microstructural evolution in the sintered paste will also be addressed.

Purpose: Our aim was to determine if a close surgical margin (

An advanced packaging configuration of a dual-active-bridge 10 kW DC-DC converter module is introduced in this dissertation. Through utilization of novel heatsinks for the power switches and the transformer assembly, ~20 kW/Lit converter volumetric power density based on numerical and experimental analysis is obtained. Through a unique placement of the high power/high frequency SiC switches on the printed circuit board, many beneficial features such as double-sided cooling, complete elimination of wirebonding, and circumvention of the need for TIM layers between the switches and the heatsinks, and multi functioning heatsinks as electrical busbars is achieved. A Vertically Enhanced Manifold Microchannel System (VEMMS) cooler is developed to address the thermal challenges of a pair of power switches, simultaneously. Both air and liquid cooled versions of VEMMS cooler is presented, thermal resistances of 1.1 K/W and 0.3 K/W for the air and liquid cooled versions, respectively, at reasonable flow rates and pressure drops was obtained. Besides the power switches, thermal management of the transformer assembly is accomplished via Combined Core and Coil (C3) Coolers, where both the magnetic core and coils are liquid cooled simultaneously with electrically insulating but thermally conductive 3D printed Alumina heatsinks, where thermal resistances as low as 0.3 K/W for the magnetic core and 0.09 K/W for the transformer windings is experimentally demonstrated. Furthermore, a system level model was built to investigate the effect of various components in the cooling loop on each other, and what are the limiting factors to prevent a possible thermal runaway failure. Lastly, using a metamodeling approach, closed form pressure drop and heat transfer correlations are developed for thermo-fluidic performance prediction of manifold microchannel heatsinks. Due to complexity and vastness of design variables present in manifold microchannel systems, adequate CFD analysis and optimization require significant computational power. Through utilization of the developed correlations, orders of magnitude reduction in computational time (from days to milliseconds) in prediction of pressure drop and heat transfer coefficient is demonstrated. Extensive mesh independence and residual convergence algorithms are developed to increase accuracy of the created database. Between the correlation and mesh independent CFD results, a mean error of 3.9% and max error of 24% for Nusselt number, and a mean error of 4.6% and max error of 37% for Poiseuille Number predictions are achieved.

This study aimed to compare the hem-o-lok polymeric clip (HC) and tri-staple (TS) methods used in dividing the splenic hilum in terms of results, and to reveal their superiority to each other.Medical records of patients undergoing elective laparoscopic splenectomy at the Ondokuz Mayis University Faculty of Medicine General Surgery Clinic between March 2011 and March 2020 were retrospectively analyzed. Forty-two laparoscopic splenectomy cases performed using hem-o-lok polymeric clip (HC) or tri-staple (TS) were included in this study. Demographic features, primary diagnoses, splenic size, intraoperative data and postoperative complications, as well as the clip and stapler prices used in the surgery were analyzed.The mean operative time was significantly longer for HC group than TS group (116.7 min vs. 87.6 min, p0.05). The mean cost of surgical instruments used to divide the splenic hilum was significantly lower for HC group than TS group (34.1 usd vs. 165.4 usd, p0.05). There was no postoperative mortality, with a morbidity rate 6 (26.1%) for TS group and 4 (21.1%) for HC group (p0.05). No significant difference existed in the complication rates.In the HC group, the operation time was longer, but the surgical cost was significantly lower. There was no significant difference when comparing other perioperative results. Although both techniques can be applied safely, we would like to emphasize that hemostasis is the most important factor for good results.Hem-o-lok polymeric clip, Laparoscopic splenectomy, Tri-staple.Studio finalizzato a confrontare l’impiego di clip polimerica hem-o-lok (HC) con il tri-stapler (TS) utilizzati nella sezione-emostasi dell’ilo splenico in termini di risultati e di valutare la loro eventuale reciproca superiorità. Sono state analizzate retrospettivamente le cartelle cliniche dei pazienti sottoposti di elezione a splenectomia laparoscopica presso la Clinica di Chirurgia Generale della Facoltà di Medicina dell’Università di Ondokuz Mayis tra marzo 2011 e marzo 2020. Sono stati inclusi in questo studio quarantadue casi di splenectomia laparoscopica eseguiti con clip polimerica hem-o-lok (HC) o tri-stapler (TS), analizzando le caratteristiche demografiche, le diagnosi preoperatore, le dimensioni spleniche, i dati intraoperatori e le complicanze postoperatorie, nonché i prezzi di clip e pinzatrice utilizzati nella chirurgia. RISULTATI: il tempo operativo medio è stato significativamente più lungo per il gruppo HC rispetto al gruppo TS (116,7 min vs. 87,6 min, p0,05). Il costo medio degli strumenti chirurgici utilizzati per dividere l’ilo splenico risulta significativamente inferiore per il gruppo HC rispetto al gruppo TS (34,1 usd vs. 165,4 usd, p0,05). Non si è riscontrata mortalità postoperatoria, con un tasso di morbilità 6 (26,1%) per il gruppo TS e 4 (21,1%) per il gruppo HC (p0,05). Nessuna differenza significativa è stata rilevata nel tasso delle complicanze. CONCLUSIONI: Nel gruppo HC, il tempo di operazione è stato più lungo, ma il costo chirurgico è stato significativamente più basso. Non ci sono state differenze significative nel confronto con altri risultati perioperatori. Sebbene entrambe le tecniche possano essere applicate in modo sicuro, vorremmo sottolineare che l’emostasi è il fattore più importante per ottenere buoni risultati.

Wide bandgap semiconductors, such as silicon carbide (SiC), have properties that allow them to surpass the performance of conventional silicon (Si) semiconductors in power electronic applications. Placing these wide bandgap devices in 3D-integrated packaging structures offers potential for significant power density increases as well. This paper addresses the thermo-mechanical design considerations in such a package containing a full bridge DC-DC converter with multifunctional heat sinks directly bonded to bare-die SiC MOSFET’s, as well as additively manufactured transformer windings. This structure is accomplished by developing and incorporating innovative design practices with additive manufacturing technology and multi-functional elements that will serve combined mechanical, electrical, and thermal functions. The following critical elements of this innovative converter are highlighted: the demonstration of a syringe-printed transformer winding using nano-silver paste, and flip-chipped SiC switching devices bonded via Ag-In based transient liquid phase sintering (TLPS).

This paper presents electro-thermal design optimization of a high-frequency planar transformer with an integrated thermal management system involving a liquid-cooled chamber for combined core and winding cooling. The designed transformer is for a 10 kW, 600V to 800 V, 1 MHz dual-active-bridge converter, working as the dc-dc stage of high power-density on-board electric vehicle chargers. Effect of design variables like number of turns of the transformer and cooler height on the transformer’s electrical parameters such as leakage inductance, ac resistance and parasitic capacitance is estimated. The dependence of converter efficiency on these parameters is estimated using simulations and analyses and potential trade-offs of the design are investigated. Similarly, thermal modeling is used to characterize the thermal performance of different designs, evaluated on the basis of the required coolant temperature to maintain the transformer winding and core at a specified temperature. Based on a combination of the preceding analyses, optimal designs are identified which simultaneously ensure good electrical and thermal performance.

This abstract was not presented at the symposium.

The continuous rise in heat dissipation of integrated circuits necessitates advanced thermal solutions to ensure system reliability and efficiency. Thermoelectric coolers are among the most promising techniques for dealing with localized on-chip hot spots. This study focuses on establishing a holistic optimization methodology for such thermoelectric coolers, in which a thermoelectric element’s thickness and the electrical current are optimized to minimize source temperature with respect to ambient, when the thermal and electrical parasitic effects are considered. It is found that when element thickness and electrical current are optimized for a given system architecture, a “heat flux vs. temperature difference” Pareto frontier curve is obtained, indicating that there is an optimum thickness and a corresponding optimum current that maximize the achievable temperature reduction while removing a particular heat flux. This methodology also provides the possible system level ΔT’s that can be achieved for a range of heat fluxes, defining the upper limits of thermoelectric cooling for that architecture. In this study, use was made of an extensive analytical model, which was verified using commercially available finite element analysis software. Through the optimization process, 3 pairs of master curves were generated, which were then used to compose the Pareto frontier for any given system architecture. Finally, a case study was performed to provide an in-depth demonstration of the optimization procedure for an example application.