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This study aims to investigate the low-velocity impact response of boron nitride nanoparticles (BNNPs) added carbon fiber reinforced pipes (CFRPs) at various temperature values. Carbon fiber/epoxy composite specimens with (±55°)3 winding angles were manufactured with the filament winding method. Low-velocity impact tests were performed with a 15 J energy level at five different temperatures between −196°C and 23°C ranges to understand the cryogenic environment effect on BNNP added carbon fiber reinforced tubes and neat carbon fiber reinforced tubes. The force-displacement and contact force-time graphs were attained in consequence of low-velocity impact tests. The damage areas, their size and characteristics were scrutinized both visually and with the aid of a Microscope. The test results showed that when ambiance temperatures decreased, the damage areas considerably increased both filled with BNNP and without BNNP filament wound carbon fiber reinforced tubes.

Conversion of syngas (CO + CO2 + H2) to dimethyl ether (DME) with in–situ steam separation is modeled in a membrane integrated, isothermal catalytic microchannel reactor. Reaction channel, involving washcoated form of physically mixed Cu–ZnO/Al2O3 and HZSM–5 catalysts, is separated from the permeate channel by a supported sodalite (SOD) membrane layer. Conservation of momentum and mass within the porous washcoat and the channels, and cross–membrane material transport are modeled in two dimensions at steady–state to elucidate the effects of temperature, pressure, syngas composition and permeate flow properties. Dosing syngas to both channels at 523 K, 50 bar, CO2/COx (COx: CO + CO2) = 0.5 and H2/COx = 2.0 gives CO and CO2 conversions, and DME yield of 33.2, 12.4 and 15.3 %, respectively, which are 29.9, 7.2 and 12.7 % without membrane. These findings are coherent with relaxed thermodynamic limitations on methanol synthesis and dehydration upon selective H2O removal. Higher permeate syngas flow rates promote steam efflux and H2 influx across the membrane and further elevate CO2 conversion and DME yield up to 15.8 and 17.4 %, respectively. These metrics can be improved up to 23.4 and 22.9 %, respectively upon dosing pure H2 as the permeate fluid. However, a positive pressure gradient from reaction to permeate channel does not improve reactor performance. Coherent with its higher dehydration activity, HZSM–5 responds to membrane assistance stronger than γ–Al2O3.

In this study, the impact behaviors of nano silica (SiO2 nanoparticles), MWCNTs (multi-walled carbon nanotube), and SiO2+MWCNTs (nano silica vs multi-walled carbon nanotube hybrid) nanoparticle additives in basalt fiber reinforced composites exposed to seawater corrosion were investigated. The Mediterranean was chosen as the corrosive sea water due to its high salinity. Basalt fiber reinforced composites immersed in seawater have quick mass absorption during the first 30 days. However, it can also vary between the first 28 and 40 days depending on the structure of the composite and environmental conditions. Immersion times were determined as 0, 10, 20, and 40 days. Tensile and low velocity impact tests were performed to evaluate the mechanical performance after seawater corrosion. Low velocity impact tests were carried out at 10 and 20 J energy levels. The aim of this study was to examine the effects of corrosion caused by quick mass absorption on the tensile and impact behaviors of basalt fiber reinforced composites. And also to investigate the contribution of SiO2 and MWCNT nanoparticle additives to the mass absorption mechanism and mechanical performance of basalt fiber reinforced composites. SiO2 and MWCNT nanoparticle additives increased the tensile and impact strength of basalt fiber reinforced composites. However, the tensile and impact behaviors of nanoparticle filled and nanoparticles unfilled basalt fiber reinforced composites were adversely affected by the seawater corrosion environment. Due to the geometric structure of SiO2 nanoparticles, the best mechanical performance was observed in SiO2 filled basalt fiber reinforced composites.

Objectives The determinants of right ventricular (RV) recovery after successful revascularization in ST-elevation myocardial infarction (STEMI) patients are not clear. Besides, the relationship between Troponin T (TnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP) and improvement in RV function is also unknown. This study hypothesizes that a lower TnT and NT-proBNP level would be associated with RV recovery. Methods One hundred forty-eight STEMI patients were included in our study. Echocardiography were performed before and 12–18 weeks after discharge. Patients were divided into three groups according to the changes in tricuspid annular plane systolic excursion (TAPSE) as 53 patients with ≥10% change, 41 patients with 1–9% change, and 54 patients ≤0% change. RV recovery was accepted as ≥10% TAPSE improvement and the predictors of RV recovery were investigated. Results RV recovery was detected in 35.8% of the patients. Low baseline left ventricular ejection fraction (OR: 0.91 [0.84–0.98], p=0.023), NT-proBNP (OR: 0.93 [0.89–0.98], p=0.014), TnT (OR: 0.84 [0.68–0.93], p=0.038), inferior myocardial infarction (OR: 2.66 [1.10–6.40], p=0.028), wall motion score index ratio (OR: 0.93 [0.88–0.97], p=0.002) and post-percutaneous coronary intervention TIMI flow 3 (OR: 5.84 [1.41–24.22], p=0.015) were determined as independent predictors of RV recovery. Being in the high TnT group 4.2 times, and being in the high NT-proBNP group 5.3 times could predict the failure to achieve RV recovery. Furthermore, when high TnT level was combined with high NT-proBNP level, the odds ratio of failure to achieve RV recovery was the highest (OR: 8.03 [2.59–24.89], p Conclusions Lower TnT and lower NT-proBNP level was associated with better improvement in RV function in STEMI patients.

Synthesis of Ag, Ni, Cu metallic and Ag/Ni, Ag/Cu bimetallic nanoparticles (NPs) was carried out by using metal nitrate salts as precursors via an easy and simple wet chemical method, and the synthesized NPs were loaded into the cavities of ZSM-5 zeolite framework. L-threonine was used as a capping agent and sodium borohydride as a reducing agent. Characterization of NPs and nanoparticle-modified ZSM-5 catalysts were realized with TEM, XRD, BET, FTIR, TGA, etc. The results obtained revealed that the structure of the zeolites was well preserved after the modification with metal NPs. According to the TEM and BET results, Ag-containing nanocomposite catalysts increased average pore diameter due to the small particle size of Ag NPs such as 2–6 nm well dispersed on the surface and partial blockage of the micropores of zeolite. The catalytic activity of the prepared catalysts was tested in toluene methylation at temperatures of 300 °C, 400 °C, 500 °C and different weight hourly space velocities (WHSV). At low temperatures, the modification of NPs in the ZSM-5 matrix increased toluene methylation and p-xylene selectivity. The highest p-xylene selectivity was found to be about 51% at 400 °C, while toluene conversion at this temperature was 61% using Ag NP-modified ZSM-5 due to the perfect stability NPs on the zeolite structure. The XRD, TGA and coke formation results of used catalysts show the reusability of these catalysts due to their thermal resistance, minimal coke formation and Ag NPs stability onto the zeolite framework.

Polymer-based nanocomposites have been broadly investigated to improve its specific properties such as thermal and mechanical properties to use in different application areas. In this study, we aimed to ameliorate the desired physical properties of polyvinyl butyral (PVB) by introducing various amounts of silver (Ag) and cobalt (Co) nanoparticles (NPs) in the polymer matrix. The arc-discharge method submerged in liquid nitrogen was performed to synthesize the metal NPs. To produce hybrid nanocomposites, we demonstrated embedding Ag:Co nanoparticles in the PVB matrix via easy/low-cost solution casting process without any additional materials. In the results of analysis for nanocomposites, it was observed that there were improvements in thermal, mechanical and microwave absorption characteristics of the PVB polymer with interaction of NPs with the polymer. As a result of these interactions, the hybridization of PVB with the metal NPs resulted in the improved thermal stability since the glass transition temperature was increased from 45.6 to 55.1 °C. Besides, while the tensile strength (σ) of the bare PVB film was calculated as 20.52 MPa, the strength of the corresponding tensile strength (σ) of 1.0 wt.% Ag:Co nanocomposite film was improved to 43.41 MPa. Moreover, in order to determine the effect of these changes on the radar absorption feature of nanocomposites, one-dimensional A-Scan measurements were performed on 2–18 GHz frequency band. In the results, it was observed that 1.0%.wt Ag:Co nanocomposite film absorbed approximately 90% of the incoming energy. The characterization results revealed that a positive synergetic effect raised in the case of the modification of the PVB matrix with both Ag and Co NPs. In the light of these data, it was understood that the characteristics of PVB were improved with the NPs combining, and the usage area of that will also increase thanks to this improvement. These regenerated properties made the hybrid nanocomposite a promising substrate material with considerable potential applications for various transparent, flexible, and portable surface coatings.

Offshore wind turbine blades (OWTBs) are exposed to various types of loadings during their service life. Moreover, due to their tremendous size, huge investment costs are established, including advanced engineering materials and production process solutions. To decrease their investment cost without sacrificing their mechanical performances, advanced engineering solutions in the view of material selection and design should be implemented. With this motivation, we aimed to develop a novel laminated composite design considering reducing investment costs without compromising the bending and impact resistance of an OWTB. For this, an efficient and cost-effective design of a functionally graded composite (FGM)-like glass/carbon fibers reinforced hybrid polymer composite with a specific stacking sequence was presented. To evaluate mechanical performance of the composite structure, tensile, flexural, and to simulate environmental conditions, low-velocity impact tests were conducted. Furthermore, multi-walled carbon nanotubes (MWCNTs) were also introduced into the polymer matrix to evaluate their effectiveness in the hybridized composite. Drastic improvements in the bending strength (55.8 %) and strain (39.7 %) were obtained compared to the neat carbon fiber reinforced epoxy composites (CFs), especially with the aid of MWCNTs. According to impact tests, it was pointed out that it is possible to obtain higher impact peak forces (around 15 %) compared to neat CFs. However, MWCNTs contributed with slight increments in impact resistance but effectively restricted the impact damage propagation. This study reveals it is possible to tune the bending performance, the absorbed energy, and the damage extension by utilizing glass and carbon fiber laminates in an FGM-like structure.

Fiber-reinforced polymer composites serving in harsh conditions must maintain their performance during their entire service. The cryogenic impact is one of the most unpredictable loading types, leading to catastrophic failures of composite structures. This study aims to examine the low-velocity impact (LVI) performance of 3D woven spacer glass-epoxy composite experimentally under cryogenic temperatures. LVI tests were conducted under various temperatures ranging from room temperature (RT) to −196°C. Experimental results reveal that the 3D composites gradually absorbed higher impact energies with decreasing temperature. Besides, the effect of multi-walled carbon nanotube and SiO2 nanofiller reinforcements of the matrix on the impact performance and the damage characteristics were further assessed. Nanofiller modification enhanced the impact resistance up to 30%, especially at RT. However, the nanofiller efficiency declined with decreasing temperature. The apparent damages were visually examined by scanning electron microscopy to address the damage formation. Significant outcomes have been achieved with the nanofiller modification regarding the new usage areas of 3D woven composites.

The primary concern of fiber-reinforced polymers (FRPs) subjected to seawater environment is losing their initial mechanical performance since water can diffuse into the composite and deteriorates the fiber-matrix interface. Recent studies related to aging performance in the seawater environment have shown that introducing halloysite nanotubes (HNTs) into the polymer matrix offers a combination of an efficient barrier effect and an improved fiber-matrix interface. Hereupon, the principal objective of this study was to experimentally investigate the impact of HNTs on shear and mode II fracture performances of the seawater aged basalt fiber (BF) reinforced epoxy (EP) composites. After six months of aging in seawater, the findings indicated that HNTs reinforced multi-scale composites exhibited 34 and 46% higher shear strength and mode II delamination toughness compared to the neat specimens. Moreover, according to the dynamic-mechanical analysis, higher glass transition temperatures (8%) were obtained for the multi-scale composites. The reduction in mechanical performances induced by fiber-matrix interfacial degradation was also confirmed by scanning electron microscopy analysis. Chemical deterioration of the polymer matrix was explored by Raman spectroscopy to reveal the efficiency of HNTs induced barrier effect. As a result of these investigations, HNT modified BF/EP multi-scale composites were offered for future advanced engineering applications.

Aim: Although there are short- and long-term prognostic studies in patients with myocardial infarction (MI), the data that can be used to predict the clinical outcome following discharge is limited. Materials & methods: We analyzed creatinine kinase-MB and troponin related to myonecrosis, suppression of tumorigenicity 2 and NT-pro B-type natriuretic peptide related to myocardial stress, C-reactive protein and procalcitonin related to inflammation in 259 MI patients. Results: Being in the high group for myocardial stress (odds ratio [OR]: 3.45, 95% CI: 1.398–8.547, p = 0.004) and inflammation markers (OR: 4.30, 95% CI: 1.690–10.899, p = 0.001) predicted major cardiovascular adverse events while myonecrosis markers could not (OR: 1.70, 95% CI: 0.671–4.306, p = 0.263). Conclusion: Using multimarker risk stratification composed of inflammation and myocardial stress biomarkers improves the prediction of major cardiovascular adverse events in MI survivors.

Silver nanoparticles (AgNPs) have been recognized for their outstanding antibacterial activities, which are required for antibacterial coating materials in therapeutic applications. A bacterial resistant electrospun nanofibrous mat made of polycaprolactone (PCL) in combination with polylactide acid (PLA) containing silver nanoparticles encapsulated with Thymus vulgaris L. (thyme) extract (eAgNPs) was fabricated in order to assess the potential of applicability in biomedical applications such as cancer treatment, wound healing, or surgical sutures. In the current study, PCL and PLA used as the basis polymers were blended with biosynthesized eAgNPs, pure AgNPs, and thyme extract (TE) to observe the effects of additives in terms of antibacterial and anticancer activity and morphologic, thermal, mechanical, biocompatibility, and biodegradability properties. The biological characteristics of fabricated electrospun nanofibrous mats were evaluated in vitro. Physicochemical characteristics of the nanofibrous mats were examined by UV-vis spectrophotometry, scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX), Fourier-transform infrared spectroscopy (FTIR), mechanical tensile testing, X-ray diffraction (XRD), thermogravimetric examination (TGA), and water contact angles (WCAs). The results showed that a biodegradable nanofiber scaffold with a mean fiber diameter of 280 nm is morphologically homogeneous and highly hydrophobic, has higher tensile strength than PCL/PLA nanocomposite fiber, and is resistant to Escherichia coli and Staphylococcus aureus. The cytotoxic and anticancer properties of nanomaterials were defined using L929 and SK-MEL-30 cells. The developed material inhibited cell proliferation and led to apoptosis of cell lines. It can be suggested that the use of Thymus vulgaris L. extract-encapsulated silver nanoparticle-doped PCL/PLA nanofibers produced by the electrospinning method has the potential for cancer therapy in skin tumor cell lines.

Whole body electrical myostimulation (WB-EMS) is an alternative exercise training method. The effects of this exercise program on hemodynamics and coronary circulation have recently been investigated. However acute coronary syndrome associated with WB-EMS has not been reported before. In this case report, we present a patient who underwent WB-EMS in a sports center for weight control and admitted to the emergency department with chest pain started in the second session of the training. Her electrocardiogram showed ischemic T-wave changes in the inferior leads. Additionally, troponin levels were elevated. A coronary angiogram was performed with the diagnosis of non-ST-segment elevation myocardial infarction. Coronary angiogram revealed severe vasospasm in the right coronary artery, which resolved with intracoronary nitroglycerin. She uneventfully discharged with medical treatment. This case report is the first patient with acute coronary syndrome associated with WB-EMS in the literature.

Silver nanoparticles (AgNPs) have been recognized for their outstanding antibacterial activities, which are required for antibacterial coating materials in therapeutic applications. A bacterial-resistant electrospun nanofibrous mat made of polycaprolactone (PCL) in combination with polylactide acid (PLA) containing silver nanoparticles encapsulated with

Propagation of grape rootstocks with cuttings is one of the routine processes of viticulture. Cutting studies for nursery production under nursery conditions often fall below the expected productivity level due to biotic and abiotic stress. To increase nursery yield remains on the agenda of vine researchers. Encapsulated silver nanoparticles (AgNPs) were produced by the green synthesis method from grape seed extract (Vitis vinifera L. cv Okuzgozu) with high phenolic content and silver nitrate (AgNO). The size of AgNPs was determined by Transmission Electron Microscope (TEM) as 10–50 nm and was not agglomerated and browned in colour. The effect of AgNPs on rooting of standard lignified 41B (Vitis vinifera L. cv. Chasselas × Vitis berlandieri) rootstocks pure and with Indole 3 Butyric Acid (IBA) (control, 0.5 mg L−1 AgNPs, 0.5 mg L−1 AgNPs 50 ppm IBA, 1 mg L−1 AgNPs, 1 mg L−1 AgNPs 50 ppm IBA and 50 ppm IBA) were tested. The effects of the applications on the cuttings in the greenhouse 1:1 perlite peat medium, leaf chlorophyll content, vegetative growth parameters and the effects on the vascular tissues were evaluated by micro tomography (microCT). Applications of pure AgNPs and combined with IBA did not altered the leaf chlorophyll content. While 1 mg L−1 AgNPs application, which was the closest level to 50 ppm IBA, provided the root and shoot development, while the application of 1 mg L−1 AgNPs encouraged the development of shoot most. The 1 mg L−1 AgNPs + 50 ppm IBA application resulted in the highest number of nodes in shoots developing from cuttings. In microCT analysis of rooted and unrooted grapevine cuttings, tissue damage was determined that was attributed to result in drying due to embolism and loss of nursery material. AgNPs applications are thought to increase the nursery success in grapevine rootstock cuttings.

Coronary artery origin anomalies are rare congenital anomalies. They can cause sudden cardiacdeath. They may cause technical difficulties during intervention in patients with a diagnosis of acutecoronary syndrome. In this article, the diagnosis and intervention of a case with acute inferoposteriormyocardial infarction and right coronary artery origin anomaly, who underwent successful percutaneoustransluminal coronary angioplasty and stenting, is presented with angiographic images., Koroner arter çıkış anomalileri nadir görülen konjenital anomalilerdendir. Ani kardiyak ölümlere sebepolabilirler. Akut koroner sendrom tanısı ile gelen hastalarda girişim sırasında teknik güçlüklere nedenolabilirler. Bu yazıda Akut inferoposterior miyokart infarktüsü ile gelen sağ koroner arter çıkış anomalisibulunan, başarılı perkütan transluminal koroner anjiyoplasti ve stent uygulanan olgunun tanısı vemüdahalesi anjiografik görüntüler ile sunulmaktadır.

Although they enable for facile disassembly and inspection of critical assemblies, bolted joints are common damage initiation sites in laminated composite structures. Sudden failure can occur at these locations especially with the combination of corrosive environments. In order to well understand and characterize for marine applications, we aimed to research the impact of seawater aging and halloysite nanotube (HNT) nano reinforcements on the bearing performance of basalt-epoxy composites. For this, basalt fabrics were impregnated with HNT modified epoxy matrix via vacuum infusion and the resultant multi-scale laminates submerged in seawater up to 6 months after assembling via bolted joints. Single shear tensile tests of seawater aged joints were performed according to ASTM D5961 and the results compared with the HNTs reinforced hybrid laminates. HNTs nano reinforcements remarkably improved the bearing strength basalt/epoxy composite laminates with a 18% increase. In addition, seawater aging drastically impairs the bearing response of composite laminates with an almost 45% reduction in bearing strength after 6 months of exposure. Bearing fracture modes were also affected with the addition of HNTs and seawater aging, the resultant fracture surfaces were examined to reveal degradation mechanisms related to seawater aging and HNTs reinforcement after single shear tensile tests. The results can contribute to a better understanding of mechanical design parameters for bolted fiber reinforced polymer composites exposed to corrosive environments.

Three-dimensional polymer composites offer various features and design options due to their hollow structure and lightweight. However, to exploit their advantages, it is a must to improve their structural features and mechanical performances including out-plane direction. Although introducing thermoplastic fillers between the plies or multilayered design addresses on this critical issue, the benefits offered by the nanoparticles with superior mechanical properties come a step forward as an another engineering solution. Based on this motivation, the goal of this study is to investigate the impact of multiwalled carbon nanotubes on the mechanical and thermomechanical performances of three-dimensional woven glass/epoxy spacer composites. Therefore, multiwalled carbon nanotubes at various content were introduced into epoxy matrix, and the multiwalled carbon nanotubes–epoxy mixture was infused to three-dimensional woven fabric with the vacuum-assisted resin transfer method. The obtained results indicated that the three-point bending strength and modulus were enhanced up to 25 and 80% for warp direction and enhanced up to 44 and 85% for weft direction with carbon nanotube addition, respectively. Tensile strength developed in the warp direction by 7%, while the strength value in the weft direction did not change. The tensile strain values for warp and weft directions enhanced up to 19 and 12% with carbon nanotube addition, respectively. In addition, thermomechanical analysis has revealed that the glass transition temperature and storage modulus were also improved. Particle dispersion detection with color measurement and scanning electron microscopy analyses revealed the effectiveness of the ultrasonic mixing on the dispersion of carbon nanotubes in the epoxy matrix. The consequences of carbon nanotube addition on microscale morphology were discussed based on the fracture morphologies to nanoscale and microscale toughening mechanisms in the existence of carbon nanotube reinforcement.

Glass/carbon fiber reinforced hybrid composites are great candidates for wind turbine blade manufacturers to make larger blades. Variation of stacking sequences ensures design freedom to the composite engineers to optimize the composite structure's mechanical performance. On the other hand, matrix modification of polymer composites with nanoparticles is also of interest to introduce multifunctional properties. This research aims to scrutinize the influence of simultaneous fiber hybridization and matrix modification on polymer composites’ tensile, flexural, and low-velocity impact properties. Hybrid glass/carbon epoxy composites and hybrid glass/carbon/multi-walled carbon nanotube (MWCNT) multiscale polymer composites of stacking sequences [GCGCGC]S, [CGCGCG]S, and [G6C6] were manufactured. Fiber hybridization dramatically improved tensile strength between 51% and 76% compared to glass fiber composite. Depending on the stacking sequence, the flexural strength of the hybrid composites was improved between 10% and 16% concerning carbon fiber composite. With the introduction of MWCNTs, a slight increase in the tensile strength for unsymmetrical hybrid composites by around 5% and decreases by 7% for symmetrical ones were observed. Similar behavior was seen for bending characteristics. Additionally, low-velocity impact tests showed that it is achievable to bring greater impact peak forces up to 70% for hybrid composites than carbon fiber epoxy composites. MWCNTs modification of the matrix restrained the impact damage propagation, as proved by C-scan analysis.

This review focuses on the recent advances in CO2 adsorbents and H-2 permselective membranes that can be integrated to catalytic ethanol and glycerol steam reforming for improving purity and throughput of H-2, the key input of mobile and stationary fuel cells and of hydrogenation operations of conventional and bio-refining. Combined with the decentralized availability of ethanol and glycerol, integrated reforming-separation strategies offer the advantage of on-site production of pure H-2 with environmental footprints, capital and operating expenses below those of the conventional natural-gas based steam reforming technologies. The review also covers metal organic framework membranes, the materials that offer fluxes significantly superior to those of the existing counterparts, in the context of their hydrothermal stability needed for steam reforming. (c) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

The use of nanomaterials is gradually increasing with the progress of nanotechnology. In particular, the production of nanocomposites incorporating nanoparticles is one of the most significant areas in which nanomaterials are being used increasingly. The first objective of this research was to detect the punch shear or penetration resistance behavior and damage mechanisms of hybrid nanocomposites obtained by using silica (SiO2) nanoparticles. For that purpose, six different SiO2 hybrid nanocomposites with different laminations three layer (3La), 5La, 7La, 11La, 15La and 21La and different thicknesses (HC) of 0.95∼4.98 mm, were made by using vacuum assisted transfer molding (VARTM). During this research, quasi-static punch-shear (QS-PS) tests at span punch ratios (SPRs) of 1.16, 1.33, 1.67, 2.00, 2.33, 2.67, and more were conducted to determine quasi-static penetration mechanics and penetration resistance behavior. Moreover, deflection, energy dissipation, damage area, stiffness, and peak force values were investigated through experimental results and scanning electronic microscope (SEM) images.

Background and Aim One of the most worrying complications of primary percutaneous coronary interventions is contrast-induced nephropathy (CIN) that is associated with increased mortality and morbidity in myocardial infarction. In this study, we questioned whether soluble suppression of tumorigenesis-2 (sST2), which has thought to play a role in inflammatory processes, cardiac remodeling, and fibrosis could give an idea about the development of CIN in ST-elevation myocardial infarction (STEMI) patients. Patients and Methods This study is a cross-sectional observational study and includes 357 consecutive STEMI patients. Demographic features, medical history, laboratory parameters, and procedural characteristics were compared according to CIN's development. The multivariate logistic regression analysis was selected to detect independent risk factors of CIN. Results In the study, 81 patients (22.7%) who developed CIN were identified. The concentration of sST2 in CIN (+) group was higher than that of CIN (-) group (40.6±21.0 ng/mL vs 31.5±13.0 ng/L, p

Atherosclerosis is a chronic, progressive, inflammatory disease. Recognition of subclinical atherosclerotic vascular changes before clinical manifestation in an asymptomatic population is important for risk stratification and optimal management, which finally leads to the prevention of cardiovascular disease. We aimed to determine the risk of premature subclinical atherosclerosis by evaluating epicardial adipose tissue thickness (EATT) and arterial stiffness parameters in patients with ankylosing spondylitis (AS).We performed a prospective study of 60 consecutive patients meeting modified New York criteria for AS compared to 60 controls matched for age and sex. Patients with traditional cardiovascular risk factors were excluded. Arterial stiffness parameters and EATT (examined via echocardiography) values of all patients and control groups were measured.There was no difference between basal characteristic and echocardiographic parameters in patients with AS and in the control group. EATT and pulse wave velocity (PWV) were higher in the AS patients compared to the control group. EATT was 5.74 ± 1.22 mm and 4.91 ± 1.21 mm (EATT and PWV, markers of atherosclerosis and cardiovascular disease, were significantly higher in patients with AS than the control group. In addition, in this study, it has been shown that there is a significant relationship between PWV and EATT in patients with AS.

In general the nanoparticles increase the mechanical and impact behaviors of fiber reinforced polymer based composites. However, the effects of the hybridization of nanoparticles and their reasons over the nano scale fracture mechanisms have not been adequately studied for fiber reinforced composites. In this study, the low velocity impact responses and the mechanical behaviors were investigated for 4%wt. SiO2 nanoparticles filled BFR/Epoxy nanocomposites, 0.5%wt. MWCNTs filled BFR/Epoxy nanocomposites, 4%wt. SiO2 nanoparticles and 0.5%wt. MWCNTs nano-hybrid filled BFR/Epoxy nanocomposites and unfilled BFR/Epoxy composites. The tensile and low velocity impact tests at 10 J and 20 J of energy levels were applied to nanoparticles, nano-hybrid and unfilled BFR/Epoxy composites in order to define the effects of nanoparticles and nano-hybrid particles on the impact and mechanical features according to in accordance with ASTM D3039/D3039M-14 and ASTM D7136/7136M standards. It was observed that SiO2 nanoparticles addition to BFR/Epoxy for both 10 J and 20 J showed the highest tensile strength, maximum force, rebound energy and the lowest displacements and absorbed energy. SiO2+MWCNTs nano-hybrid addition to BFR/Epoxy improved higher low velocity impact responses and tensile strength than MWCNTs addition. The specimens of unfilled BFR/Epoxy composites showed the lowest tensile strength and maximum force and the highest maximum force, displacements and absorbed energy. Microscope and SEM analyses demonstrated that minimum failures like fiber breakages, delamination and debonding were observed by filling SiO2 nanoparticles provided the nano scale fracture mechanisms. In addition MWCNTs hybridization with SiO2 nanoparticles minimizes negative effects of MWCNTs micro size length and improved the impact and mechanical behaviors.

Laser is a device that means light amplification by stimulated emission of radiation, can be obtained in various ways and strengthens electromagnetic heat. The usage area of ​​titanium alloys has been limited to only special production vehicles in recent years due to their high costs. Today, one of the most advantageous metals for the automotive and aerospace industry due to the advances in production techniques and low weight and high resistance against corrosion. Laser welding method is one of the most important joining techniques due to its fixed properties. Power value one of the most effective parameter for joint strength. In this study, the effect of power factor on joint strength during the welding process of AISI 430 Ti stainless sheet was investigated. According to tensile test trials, observed that the rupture strength increases with the parameter of increased laser power but the value has been down after a certain point.

In this study, the reasons why the bones, which make up the skeletal system and were subjected to continuous compression, were created as a natural composite structure were investigated. They had been compared by being subjected to compression test separately together with sheep bone, wood, plastic and steel pipes prepared in the same dimensions. Thus, the advantages of being a composite material of the bone to our body were investigated by comparing with other materials; the data obtained from the experiments were evaluated and reported. Besides the results obtained from after the compression tests were supported by using the graphics and photographs.

This review focuses on the catalysis of ethanol and glycerol CO2 (dry) reforming to synthesis gas. Ethanol is currently utilized in the transportation network as a biomass-derived fuel that is added to refinery gasoline. Glycerol emerges as a continuously and undesirably accumulating side product of biodiesel, a trending renewable counterpart of the conventional diesel. Catalytic reforming of ethanol and glycerol with CO2 offer simultaneous valorization of a greenhouse gas with two renewable and commercially available fuels to synthesis gas, a value-added feedstock for the production of methanol, synthetic fuels and dimethyl ether. For the first time in the literature, catalysts for ethanol and glycerol dry reforming are reviewed on the basis of individual and interactive effects of active species and supports on reactant conversions, yield and composition of syngas, and catalyst stability. Discussions on the catalysts are complemented by the respective thermodynamic aspects. Strategies for promoting efficient transformation of ethanol and glycerol with CO2 into syngas are presented.

The impact response of adhesives is a critical design parameter considering their lifetime. Additionally, environmental effects such as water or moisture may cause to degrade of the polymer-based adhesive and shorten its service life. This study aimed to investigate the impact response of water-aged aluminium-composite adhesively bonded single lap joints (SLJs). Nylon 6.6 nanofibers modified with graphene nanoplatelets (GNPs) were introduced in the adhesion areas to increase adhesive performance. The water aging resulted in decreased impact resistance in all cases. However, nanofiber-modified SLJs exhibited comparatively higher impact performance under both non-aged and water-aged conditions. Further, the GNP reinforced nylon 6.6 nanofibers increased the maximum impact load by 15 and 19% compared to neat nanofibers before and after aging, respectively. The fracture surfaces were examined via scanning electron microscopy (SEM) to understand damage and toughness mechanisms. A schematic model has been developed to explain the mechanisms leading to improved bonding performance by applying N6.6 nanofiber reinforcement to the adhesion zone.

Bakir oksit (CuO) nanoparcaciklari, sivi bir ortamda ark desarj yontemi ile basarili bir sekilde sentezlendi. Iki bakir elektrot arasinda ark bosalmasi gercekleserek uretimi tamamlanan bakir oksit nanoparcaciklarin morfolojisi ve Kristal yapisi ayrintili bir sekilde incelenmesi yapildi. Elektron mikroskobu incelemeleri sonucunda uretilen CuO nanoparcaciklarin 10-50 nm araliginda nominal caplarda duzensiz sekilli oldugu gorulmektedir. XRD sonuclari ise sentezlenen parcaciklarin herhangi bir safsizlik olmadan sadece CuO piklerini icerdigini gostermektedir. Sonuclara gore tek fazli CuO nanoparcaciklarin uretilmesi icin ark desarj yontemi basit, ucuz ve esnek bir yontemdir.

The effects of SiC-Fe3O4 nanoparticles doped electrospun Polysulfone (PSF) nanofibers on compressive and interlaminar shear strength of glass/epoxy composite laminates were investigated in this study. Pure PSF and hybrid PSF nanofibers were synthesized by electrospinning processes. Nanofiber interleaved glass/epoxy composite laminates were manufactured by using a vacuum-assisted hand-lay-up method. Addition of SiC-Fe3O4 nanoparticles into PSF nanofibers improved tensile properties of nanofiber mats. The results revealed that PSF hybrid nanofiber interleaving increased the compressive and interlaminar shear strengths of composite laminates up to 26% and 12.4%, respectively.

The objective of this study was to investigate the effects that the application of mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP) following tendon repair have on the strength and healing of the tendon and also to examine the possible mechanisms of action that take place.The Achilles tendons of 80 rats were repaired and divided into eight groups. Following the repairs, MSCs obtained from humans were injected into the rat tendons in groups 1 and 2, a combination of MSCs from humans and PRP from rats was injected into the tendons in groups 3 and 4, and PRP from rats was injected into the tendons in groups 5 and 6. These procedures all took place simultaneously. Groups 7 and 8 did not receive any injections following the repairs. The rats were sacrificed at the end of the first and second months following the procedures, and biomechanical and histopathological analyses were performed.Inflammatory cell density increased most significantly in the combined group when compared to the first and second months. T he fibroblast density on the tendon repair region was significantly lower in the second-months groups of each intervention compared to their first-month groups (p = 0.001). For the analysis of the maximum tensile breaking force, the behaviors of the groups over time were significant when compared to the control groups (p = 0.0015). Also, the mean maximum breaking force in the combined group was statistically significantly higher at the end of the second month than at the end of the first month (p = 0.0008).

Quasi-static (QS) punch shear damage of a composite material is an important damage mode during the penetration and perforation of fibre-reinforced composites and also QS punch shear penetration re...

In this study, we report the effect of halloysite nanotube (HNT) modification on salty water aging durability of epoxy (Ep)/basalt fiber (BF) hybrid composites. For this, various amounts of HNTs were introduced into the Ep matrix, and the HNTs/Ep mixture was used to impregnate basalt fabrics to fabricate hybrid laminated composites. The hybrid composites were exposed substantial increases in the tensile strength and the fracture toughness. Besides, after salty water aging for 6 months, the hybrid composites exhibited remarkably improved aging performance with almost 10 % less reduction in both tensile and flexural strengths and fracture toughness compared to the neat basalt-epoxy composites. SEM analysis showed relatively less number of cracks, micro-voids and better interfacial bonding for the 2 wt% HNTs reinforced hybrid composite specimens in comparison to the neat counterpart, similarly conditioned in all cases. The consequences of salty water aging on micro-scale morphology were discussed based on the fracture morphologies to reveal degradation mechanisms in the existence of HNTs reinforcement.