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Abstract Three-dimensional (3D) printing has become a potent production tool in the field of biomedical engineering over the past 20 years. Through layer-by-layer deposition of materials, proteins, and even living cells, it offers considerable advantages in the creation of sophisticated and individualized biomedical products with accuracy, efficiency, cost effectiveness, and reproducibility. Despite the tremendous advances made in 3D printing, more work needs to be done to improve the quality of biomedical goods created with this technology. To assure the creation of remarkable and ground-breaking goods that address patients’ demands, numerous challenges in 3D printing processes, materials, and applications must be addressed. It is necessary to incorporate developments in physics, materials science, engineering, biological sciences, and medicine to meet these problems. This article reviews a variety of 3D printing-related issues in the biomedical industry, including processes, post-processing techniques, applications, and related difficulties. It analyzes the difficulties 3D printing in biomedical engineering faces and makes suggestions for potential future advancements. It is obvious that 3D printing is becoming more and more important in this field and has the ability to provide a wide variety of useful biological items. This review seeks to identify future directions for research and development while also advancing understanding of the existing state of 3D printing and the effect of post-processing in biomedical engineering. Graphical Abstract

Objective: The currently available cardiac biomarkers are not sufficient to differentiate between myocardial infarction with non-obstructive coronary arteries (MINOCA) and acute coronary syndrome (ACS) without the use of coronary angiography. In this context, this study aimed to evaluate inducible nitric oxide synthase (iNOS) activity as a potential marker for the differential diagnosis of MINOCA and ACS. Method: The study population comprised 734 consecutive patients who presented to our hospital with chest pain between July 2022 and January 2023. Leftover plasma samples collected in EDTA vials were sent for troponin T estimation within 24 hours of the onset of chest pain. Patients’ blood samples were collected into tubes for malondialdehyde (MDA), iNOS, and total sialic acid (TSA) measurements and centrifuged at 4000 g, 4 °C for 10 min, and the sera obtained as a result were kept at -25 °C until the analyses were performed. Results: The mean age of the study population, which consisted of 648 patients [421 (65.6%) males, was 62±12] years. There were no significant difference between the MINOCA and ACS patients in MDA and homocysteine levels. Univariate logistic regression analysis revealed significant correlations between gender, age, diabetes mellitus (DM), glucose, urea, iNOS, smoking, hemoglobin, platelets, lymphocytes, monocytes, neutrophils, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, creatine, and TSA as significant predictors of MINOCA. Further analysis of these variables using multivariate logistic regression revealed that sex, age, presence of DM, glucose and urea levels, and iNOS were independent predictors of MINOCA. The iNOS level was significantly higher in patients with MINOCA than in those with ACS. The optimal iNOS cut-off value of >1372.9 pg/mL predicted MINOCA with 99.4% sensitivity and 93.7% specificity (area under the curve: 0.99, 95% confidence interval: 0.979-0.996, p

The genus Lacerta, particularly the green lizard (Lacerta viridis), is a significant lizard group in the Western Palearctic. This study aims to predict its geographic range in Northern Türkiye and identify key habitat types based on the CORINE Land Cover classification. Occurrence records, gathered from published sources and on-site investigations, were analyzed using a 30 arc-second resolution layer and bioclimatic parameters from WorldClim v.2.1. The distribution was modeled in kuenm, and habitat use was assessed with generalized linear models. Results show that the green lizard’s occurrence is strongly influenced by precipitation dynamics and it prefers areas with little to no shade. These findings highlight the importance of precipitation in determining the species’ distribution and suggest further research on local dynamics for effective conservation.

Background: Optic neuritis, myelitis, and neuromyelitis optica spectrum disorder (NMOSD) have been associated with antibodies against myelin oligodendrocyte glycoprotein-immunoglobulin G (anti-MOG-IgG). Furthermore, patients with radiological and demographic features atypical for multiple sclerosis (MS) with optic neuritis and myelitis also demonstrate antibodies against aquaporin-4 and anti-MOG-IgG. However, data on the diagnosis, treatment, follow-up, and prognosis in patients with anti-MOG-IgG are limited. Aims: To evaluate the clinical, radiological, and demographic characteristics of patients with anti-MOG-IgG. Study Design: Multicenter, retrospective, observational study. Methods: Patients with blood samples demonstrating anti-MOG-IgG that had been evaluated at the Neuroimmunology laboratory at Ondokuz Mayıs University’s Faculty of Medicine were included in the study. Results: Of the 104 patients with anti-MOG-IgG, 56.7% were women and 43.3% were men. Approximately 2.4% of the patients were diagnosed with MS, 15.8% with acute disseminated encephalomyelitis (ADEM), 39.4% with NMOSD, 31.3% with isolated optic neuritis, and 11.1% with isolated myelitis. Approximately 53.1% of patients with spinal involvement at clinical onset demonstrated a clinical course of NMOSD. Thereafter, 8.8% of these patients demonstrated a clinical course similar to MS and ADEM, and 28.1% demonstrated a clinical course of isolated myelitis. The response to acute attack treatment was lower and the disability was higher in patients aged > 40 years than patients aged < 40 years at clinical onset. Oligoclonal band was detected in 15.5% of the patients. Conclusion: For patients with NMOSD and without anti-NMO antibodies, the diagnosis is supported by the presence of anti-MOG-IgG. Furthermore, advanced age at clinical onset, Expanded Disability Status Scale (EDSS) score at clinical onset, spinal cord involvement, and number of attacks may be negative prognostic factors in patients with anti-MOG-IgG.

This research focuses on designing, computationally modeling, and assessing a novel sunken greenhouse equipped with wind towers to create an optimum microclimate capable of enhancing crop productivity and quality while minimizing energy consumption in hot arid climates that present challenges like extreme ambient temperatures and intense solar irradiation. Three innovative, energy-efficient, and cost-effective techniques were integrated into the proposed greenhouse design: (1) Wind tower-driven natural ventilation, (2) fully sunken greenhouse structure, and (3) direct evaporative cooling. The airflow dynamics, solar heat transfer, and the interaction of moist air within the greenhouse environment were investigated to analyze the system’s performance and optimize its design. The results showed efficient ventilation rates and great improvement in the greenhouse’s internal microclimate in terms of temperature and relative humidity. The average airflow velocity inside the greenhouse, measured at 1 m height, ranged from 0.11 to 0.69 m/s for nominal wind speeds of 1–6 m/s, while air changes per minute range is 0.28–1.7. Even under extreme ambient conditions (30–45 °C, 15–50 % humidity), the proposed greenhouse mostly maintained temperatures below 35 °C, reducing interior air temperatures by up to 11.7 °C from the ambient and increasing humidity by up to 57.1 %. The economic feasibility comparison of the proposed greenhouse to a conventional active-cooled greenhouse showed a remarkable 74.5 % reduction in the life cycle cost of the microclimate control technique.

The urgent global challenges of climate change and resource overconsumption highlight the need for sustainable innovations in the construction industry. Ordinary Portland cement, a vital construction material, significantly contributes to carbon emissions. Alkali-activated materials have emerged as promising alternatives. Three-dimensional printing (3DP) has gained attention in construction, because it offers efficiency and sustainability benefits. This study addresses the integration of alkali-activated materials and 3DP, focusing on circular economy implications. This study examines 1200 research articles from the Scopus database and comprehensively reviews 47 articles on 3DP of geopolymer structures. This study identifies critical research gaps, including a lack of focus on 3DP for alkali-activated materials, circular economy models, optimal mixtures, anisotropy mitigation, reinforcement strategies, and scalability. These insights highlight the transformative potential of 3DP with alkali-activated materials in sustainable construction, fostering a circular economy.

In the era of smart and sustainable technology driven by naturally occurring materials, various nanocellulose-based materials play a crucial role. Shape memory behaviour and self-healing capabilities of nanocelluloses are emerging as focal points in numerous research domains. Nanocellulose and its derivatives such as cellulose nanocrystals (CNC) and cellulose nanofibers (CNF), are currently in the limelight due to their excellent shape-memory and self-healing properties, making them suitable for multifunctional devices. In this regard, CNF, as a cutting-edge material, has spurred researchers to explore its potential in developing contemporary multifunctional and personalized health devices. Therefore, a timely and comprehensive review is essential to gain deep insights into the effectiveness of shape-memory and self-healing capabilities of CNF for multifunctional devices. Herein, we first provide a brief introduction to all nanocellulose materials. This review also depicts recent advancements and breakthroughs in the large and effective synthesis of CNF-based hybrid materials. Next, focusing on their self-healing and shape-memory performance, this review sheds new light on the advanced applications of CNF materials. Finally, perspectives on the current challenges and opportunities in this field are summarized for future researchers to gain an in-depth understanding of CNF-based smart and sustainable materials.

Understanding the external and internal factors during an additive manufacturing (AM) process is crucial, as they can significantly affect the final product's performance. Efforts have been made to unwind the product, process, property, and performance (PPPP) relationships. The conventional experimental approaches can lead to boundless runs, resulting in exorbitant costs for research and development. Hence, developing, adapting, and validating numerical models is essential to achieving the desired performance of 3D-printed products with lesser resource utilization. In this study, numerical and experimental techniques were used to perform the PPPP relationship assessment on material extrusion 3D-printed parts. Three infill designs (rectangular, triangular, and hexagonal), with layer heights (0.1 mm, 0.125 mm, and 0.2 mm), and three different materials (carbon fiber-reinforced polyamide-6 (PA6-CF), polyamide-6 (PA6), and acrylonitrile butadiene styrene (ABS)), were selected for the investigation. Taguchi's design of experiments (DOE) method was used to limit the number of numerical simulations and experimental runs. A thermomechanical numerical model was utilized to perform the material extrusion process simulations and mechanical performance prediction of the specimens. Subsequently, the samples were 3D-printed and tested mechanically to validate the numerical simulation results. The dimensional, distortion, and mechanical analysis performed on numerical simulation results agreed well with the experimental observations.

Polymers and their composites are now widely used in several industrial sectors, owing to their flexibility in developing customized products. The significant surge in plastic usage has led to a severe challenge in managing end-of-life plastic waste. Millions of tons of plastic waste produced annually mainly end up in landfills, leaking into the environment and posing severe threats to ecosystems. Innovative solutions to reuse/recycle/repurpose plastic waste are desired to address these global challenges. Therefore, in this study, a sustainable route to converting plastic waste into additive manufacturing (AM) feedstock is presented, where waste plastic bottles (mainly Polyethylene Terephthalate, PET) are recycled using an in-house 3D-printed filament extrusion system to produce filaments for fused filament fabrication (FFF) process. In addition to the recycled PET (rPET), virgin carbon fiber reinforced polyamide-6 (PA6-CF) polymer composites were also used to produce hybrid feedstock filaments. The rPET and rPET/PA6-CF composite filaments were extruded using an in-house filament extruder setup. The produced rPET-based filaments were characterized for their chemical and thermal properties. Subsequently, mechanical characterization was performed on 3D-printed specimens. The mechanical analysis revealed better tensile strength for rPET/PA6-CF than rPET; however, the rPET demonstrated better failure strain and young modulus, demonstrating their potential as viable materials for industrial and consumer applications. The outcomes of this study revealed promising results to promote sustainable production and consumption, complementing the circular economy practices with a straightforward production route to convert plastic waste into AM feedstock.

Bone tissue engineering (BTE) holds promise for treating bone defects, and 3D-printed porous scaffolds are pivotal for tissue regeneration. This study explores the impact of material extrusion 3D printing (ME3DP) process parameters (i.e., layer height and extrusion temperature) on 3D-printed porous scaffolds made of polyetherimide (PEI) material for BTE. The intricate relationships shaping scaffold dimensional accuracy, residual stresses, and warpage tendencies were unveiled using comprehensive numerical simulations. Our findings reveal that higher layer heights enhance dimensional stability, especially at lower printing temperatures, reducing maximum displacements. Consequently, lower layer heights lead to higher warpage critical values. This insight is instrumental in optimizing the material extrusion 3D printing (ME3DP) process, vital for precise net shape in BTE applications. Furthermore, residual stresses also revealed a correlation between higher printing temperatures and increased residual stresses. These findings emphasize the necessity of balancing material flow, printing temperature, and layer height for scaffold quality. Therefore, the right balance between precision and mechanical stability is critical for producing high-quality scaffolds that meet BTE requirements.

The transition to cleaner energy sources, including renewables, introduces the need for versatile and transportable energy carriers such as hydrogen. This paper aims to quantify the hydrogen export competitiveness of all countries using a newly developed comprehensive index. The developed competitiveness index includes 21 indicators under four main categories: resource availability and potential, economic and financial potential, political and regulatory status, and industrial knowledge. Expert interviews and surveys are conducted to properly identify, choose and modify the categories and indicators, and to calculate the appropriate weight for each. Top-ranking countries include the United States, Australia, Canada, United Kingdom, China, Norway, India, Russia, Netherlands, and Germany, and they are poised to be significant players in the hydrogen market. Policy recommendations for growing the hydrogen production and export sector are given based on each category.

Numerical modeling and simulation approaches can be used to optimize material combinations, structural design, and process parameters to achieve the desired structural performance of 3D-printed structures. In this study, a novel CDW-based mortar mixture was prepared for the 3D concrete printing (3DCP) process. A square cross-sectional structure was designed and 3D-printed using a lab-scale gantry-type 3D printer for buildability analysis. The geopolymer material was also characterized to obtain time-dependent properties for use in a numerical model capable of predicting the buildability of concrete structures. In the numerical modeling and simulation phase, predictive simulations were performed for experimentally 3D-printed structures to validate the predictability of the numerical model. The numerical model revealed a sound approximation of buildability with an error of 6.3% only. Furthermore, using numerical simulations, sensitivity analyses were performed to evaluate the impact of designed height and 3DCP process parameters (i.e., printing speed and layer width) on the buildability of structures. The numerical modeling and simulation results revealed a strong impact of both process parameters (i.e., printing speed and layer width) on the buildability of 3D-printed structures. A maximum buildability of 410.6mm was achieved for structure 3D-printed at a printing speed of 20mm/s and layer width of 45mm. Overall, an improved buildability was observed for lower printing speeds and higher layer widths; however, the buildability performance was more sensitive to the layer width.

Abstract Although hypertension is considered high intravascular pressure, impairing circadian blood pressure (BP) has been shown to potentially contribute to poor clinical outcomes. Systemic immune‐inflammation index (SII), based on platelet, neutrophil, and lymphocyte counts, has been established as a strong prognostic marker in cardiovascular disease. The role of inflammation in the pathogenesis of hypertension is a well‐known issue and inflammatory markers are associated with BP variability. We aimed to investigate whether there is a relationship between circadian BP changes and SII in newly diagnosed hypertensive patients. The study population consisted of 196 newly diagnosed hypertensive patients without LVH. In total, 76 (38%) patients had a dipper BP pattern, 60 (31%) patients had a non‐dipper BP pattern, and 60 (31%) patients had a reverse‐dipper BP pattern. SII was calculated according to Multivariate logistic regression analysis revealed SII and HDL‐C as an independent predictors of reverse‐dipper circadian pattern in newly diagnosed hypertensive patients. The cut‐off value of the SII for reverse‐dipper hypertension in a ROC curve analysis was >639.73 with 63.3% sensitivity and 84.2% specificity. Our study showed that the SII level was higher in the reverse‐dipper hypertension patient group than in the dipper and non‐dipper hypertension groups. Furthermore, SII was an independent predictor of newly diagnosed reverse‐dipper hypertensive patients. The high SII value in newly diagnosed hypertensive patients can be used as an early warning parameter to identify reverse‐dipper hypertension patients.

Polycaprolactone (PCL) is a biocompatible polymer readily moldable into various shapes and designs. However, its low mechanical strength and slow biodegradation restrict its use in tissue engineering. Magnesium (Mg), a biocompatible metal with excellent osteoconductivity and biodegradability, is a promising choice for tissue engineering applications. This study investigates the influence of Mg incorporation on the properties of PCL/Mg composites, aiming to evaluate their suitability for 3D-printable (3DP) tissue engineering applications. We synthesized a series of PCL/Mg composites with varying Mg concentrations and characterized their mechanical, thermal, and degradation properties. According to microscopic analysis of the composite films, the Mg particles are dispersed consistently throughout all the compositions. The findings demonstrated that adding Mg influenced PCL’s mechanical and thermal properties. The mechanical test results showed that the tensile strength of 15% Mg composite filaments improved by around 10% compared to the neat PCL filaments. However, the elastic modulus decreased by around 50% for the same composition. The thermal study revealed a significant reduction in the degradation temperature from above 400°C for pure PCL to around 300°C for PCL/Mg composite having 15% Mg. Additionally, the weight loss during in vitro degradation showed that the presence of Mg had significantly increased the degradation rate of composite samples. Also, Mg incorporation influences cell adhesion, with better attachment observed for 10% Mg 3DP samples. Overall, PCL/Mg composites offer a solution to overcome the limitation of low thermo-mechanical properties typically associated with the PCL.

Resumo Fundamento: A isquemia com artéria coronária não obstrutiva (INOCA) é uma doença cardíaca isquêmica que inclui principalmente disfunção microvascular coronariana e/ou vasoespasmo coronariano epicárdico devido à disfunção vascular coronariana subjacente e pode ser observada mais comumente em pacientes do sexo feminino. O índice de inflamação imunológica sistêmica (SII, relação plaquetas × neutrófilos/linfócitos) é um novo marcador que prediz resultados clínicos adversos na doença arterial coronariana (DAC). Objetivo: Este estudo tem como objetivo investigar a relação entre INOCA e SII, um novo marcador associado à inflamação. Métodos: Um total de 424 pacientes (212 pacientes com INOCA e 212 controles normais) foram incluídos no estudo. Amostras de sangue venoso periférico foram recebidas de toda a população do estudo antes da angiografia coronária para medir o SII e outros parâmetros hematológicos. Em nosso estudo o valor de p

3D Concrete Printing (3DCP) is a promising technology with significant advantages for the construction industry, encompassing reduced labor costs, diminished carbon dioxide emissions, enhanced time efficiency, improved user convenience, and design flexibility. To ensure optimal structural outcomes and resource efficiency, integrating numerical modeling and simulation is imperative for predicting structural behavior and identifying potential premature failures in 3DCP. Despite the recognized importance of this integration, the impact of different printing parameters on numerical models, particularly with variations in printing speed and printing layer, remains an unexplored area. This research delves into the influence of crucial printing parameters, specifically printing speed and nozzle diameter, on the buildability of 3D-printed structures within the built environment. A comprehensive experimental analysis is conducted on geopolymer-based 3D-printed structures, encompassing diverse process parameters associated with 3D printing (3DP) technology. A numerical model is deployed to predict the buildability of these structures, and its results are compared with experimental findings, assessing the efficacy of numerical modeling under varying printing parameter conditions. Rigorous characterization of input material properties is undertaken to ensure the accuracy of numerical simulations. Experimental results showcase favorable processability and buildability of geopolymer materials derived from novel Construction and Demolition Waste (CDW). Findings indicate that an increased nozzle size, reflected in greater layer height and width, positively influences buildability, whereas higher printing speeds correlate with reduced buildability. The numerical model successfully captures these buildability trends, though with an error ranging from 32 % to 45 % in predicting failure in 3D-printed structures. Nevertheless, the overall performance of the numerical model remains reliable in predicting the influence of printing parameters on buildability.

Life cycle assessment (LCA) is a powerful tool to evaluate the environmental impacts of any domestic or industrial activity consuming goods and services. There has been an increasing interest in recycling polymers and polymer composites for circular economy and sustainability; however, the widespread use of polymers should be avoided upfront, especially for research and development. LCA is performed to evaluate the environmental impact of two characterization approaches (numerical modeling and experimentation) used for additively manufactured polymers and composites. The current study was conducted using GaBi software, per the International Organization for Standardization (ISO) 14040 and 14044 guidelines. Five different environmental impacts, namely global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), ozone layer depletion (ODP), and fossil fuel depletion (FFD), were evaluated and compared for numerical modeling and experimental characterization approaches. Electrical energy used during the filament fabrication, 3DP process, and mechanical testing was identified as a hotspot in the environmental impacts (GWP, AP, EP, and FFD) for experimental design. However, the materials consumed during the experimental characterization contributed considerably to ODP. Results concluded that using the numerical modeling approach could significantly reduce the environmental impact caused due to extensive resource utilization in experiments. The numerical modeling approach can help promote sustainability as these tools can adequately predict the response of 3D-printed structures; therefore, they should be explored and improved further.

Background: Systemic immune-inflammatory index (platelet count × neutrophil–lymphocyte ratio) is a new marker that predicts adverse clinical outcomes in coronary artery diseases. Our aim was to investigate the relationship between the systemic immune-inflammatory index and residual SYNTAX score in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention. Methods: In this retrospective study, 518 consecutive patients who underwent primary percutaneous coronary intervention (PCI) with the diagnosis of ST-segment elevation myocardial infarction were analyzed. The severity of coronary artery diseases was determined by residual SYNTAX score. In the receiver operating characteristic curve analysis, systemic immune-inflammatory index with an optimal threshold value of 1025.1 could detect the presence of a high residual SYNTAX score; the patients were divided into 2 groups as low (326) and high (192) according to the threshold value. In addition, binary multiple logistic regression analysis methods were used to evaluate independent predictors of high residual SYNTAX score. Results: In binary multiple logistic regression analysis, systemic immune-inflammatory index [odds ratio = 6.910; 95% CI = 4.203-11.360; P

Background and Aim:The systemic immune-inflammation index (SII) has been identified as a novel prognostic marker in various illnesses. We investigated the relationship between SII and mortality in patients undergoing primary percutaneous coronary intervention (pPCI). In addition, we planned to examine how SII correlated with SYNTAX II and thrombolysis in myocardial infarction (TIMI) risk scores in this population.Materials and Methods:This retrospective observational study included patients with ST-segment elevation myocardial infarction who underwent pPCI. The endpoint was 1 year all-cause mortality. SII [(neutrophil x platelet)/lymphocyte] was calculated from admission blood samples. Besides clinical and laboratory findings, SII, Syntax II and TIMI risk scores were compared between survivors and non-survivors. The correlation between SII and Syntax II and TIMI risk scores was also evaluated.Results:The study included 334 patients (82.3% male). In the 1 year follow-up, 18 patients (5.4%) died. The SII, Syntax II, and TIMI risk scores were significantly higher in non-survivors than in survivors [mean (standard deviation: SD), 2423 (2005) vs 1686 (998), P = 0.005; median (interquartile range) 43 (35-53) vs 30 (25-37), P < 0.001; and 4 (2-5) vs 2 (1-3), P = 0.005, respectively]. Furthermore, the Syntax II score, TIMI risk score, and SII was independent predictors of 1 year all-cause mortality. SII showed a significant correlation with Syntax II and TIMI risk scores (R2 = 0.28, P = 0.001 and R2 = 0.37, P < 0.001, respectively).Conclusion:SII might provide additional prognostic data alongside Syntax II and TIMI risk scores in patients undergoing pPCI.

The importance of numerical modeling and simulation approaches increases with increased scale as it allows for early results predictions. This study evaluated the buildability of novel construction and demolition waste (CDW)-based geopolymer materials for 3-dimensional printing (3DP) structures for the built environment. The feasibility of the developed numerical model for 3DP of built environment structures was also evaluated. This study reported the fresh-state properties of geopolymer-based materials, and based on these results, numerical modeling for 3DP of geopolymer material was performed. Three cylindrical structures with diameters of 300 mm, 450 mm, and 600 mm were printed, with the same printing conditions, resulting in buildability of 352.5 mm, 322.5 mm, and 277.5 mm (total height constructed before the collapse), respectively. In the next stage of the study, a comparative analysis was performed to assess the compatibility of numerical models for CDW-based geopolymer materials. In the numerical results, three structures showed early failure prediction from experimental results at 31.91%, 29.10%, and 29.73%, respectively. The geopolymer materials developed were suitable for 3DP, and close agreement in results and repeatability were observed. The numerical model provided a reliable failure prediction for different structures. Hence, the model can be utilized to evaluate the buildability of the structures before the actual 3DP, which can significantly reduce the time and cost of the project.

The retreat of the ice around the freezing waters of the Arctic Ocean is opening new waterways where shipping activity could transport commodities between continents. One of the essential products is natural gas - LNG, which is transported in large tankers from exporters to importers. This study aims to explore the dynamics of the LNG trade by using these new tentative routes with conventional sea lanes and estimating the changes in the LNG trade. We utilize Agent-Based Modeling to develop a global LNG model with interactive GIS features, where the agents are the players in the LNG market. The results demonstrate the preponderance of the North-East Passage (NEP, Eurasian Arctic waters) over the North-Western Passage (NWP, the Canadian Arctic) in providing a shortcut connecting Europe with Asia. This passage favors a growing exporter like Russia with exporting facilities in Siberia and future strategic projects to increase liquefaction capacity. The NEP becomes crucial when considering scenarios of a European ban on Russian imports, as European countries are planning due to the crisis with Russia. On the importing side, the Asian Pacific and South Asian importers are the winners with a diverse and shorter LNG supply source. Future Canadian projects may also benefit from these new highways. However, there are also substantial challenges to providing the NEP with the proper infrastructure and systems to make the Polar LNG journeys safe and sound shortly. Beyond that, the Arctic sea corridors may alleviate the high LNG transit through the conventional routes and their chokepoints, but they are not a replacement for the conventional ones, not even with the most favorable conditions.

This study sought to determine pesticide residues in some fruits in Tokat province, Turkey and to assess the health risks associated with the determined residues. QuEChERS analytical method was verified to determine 260 pesticides by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Pesticide solutions corresponded 10 and 50 µg kg­-1 were applied to the pesticide-free apple matrix for the method verification. The linearities (R2), limit of detections, limit of quantifications and mean recovery values of the pesticides ranged between 0.990-0.999, 0.83-3 μg kg­-1, 2.76-9.99 μg kg­-1 and 70.3-119% (with relative standard deviation ≤20%), respectively. The results were evaluated according to the European Union maximum residue limits (EU-MRL). The residues were lower and higher than the EU-MRL with a ratio of 37.7% and 32.1% of the tested samples, respectively. The residue levels of diflubenzuron in apples, permethrin in cherries, and dimethoate in pears, apples, and peaches were higher than the EU-MRL. The results of health risk assessments indicated that omethoate and dimethoate have acute and chronic toxicity potential for consumers. Hence, the pesticide use in the study area must be reduced to avoid health risks. Furthermore, alternative management methods should be developed to lower the use of pesticides.

Construction and Demolition Waste (CDW)-based geopolymers are expected to lower the construction sector’s environmental impacts by reducing the use of ordinary cement and reusing waste materials and are considered a substantial step toward a circular economy and environmental sustainability in the long run. However, due to the energy-intensive mechanical, thermal, and chemical processes involved in preparing the CDW-based geopolymers, it is essential to quantify their environmental implications in the early stages of development. The objective of the study is to analyze the environmental sustainability of newly developed geopolymers containing CDWs, i.e., roof tile (RT), hollow brick (HB), red clay brick (RCB), and glass waste (G) based geopolymer binder materials. The study aims to identify the environmental impact of their critical process parameters using Life Cycle Assessment (LCA) approach and evaluate their production feasibility at a location with completely different energy and water scenarios. According to the results of the study, compared to Ordinary Portland Cement (OPC), all the CDW-based geopolymers had lower environmental impacts. G-based geopolymer binder resulted in the lowest Global Warming Potential (GWP) with a 38% reduction, followed by RT and HB with 35.3% and 34.8%, respectively. However, due to the energy-intensive processes of crushing and grinding CDWs, electrical energy is identified as a hotspot with significant environmental impacts. The replacement of mix-grid energy with hydropower reduced GWP by 63.3%, Eutrophication (EP) by 52.5%, Acidification potential (AP) by 86.4%, and fossil fuel deposition (FFD) by 74%. The highest environmental performance is calculated for electricity produced from hydropower, wind, and photovoltaics, then geothermal and biomass resources.

Tri-material and tri-layered composites find numerous applications in the biomedical, aerospace, and automotive industries. However, such composites face challenges when fabricated through conventional methods (Electrospinning, hand lay-up, Film Casting, In-situ polymerization), such as interface bond strength, strength-to-mass ratio, etc. Additive manufacturing can be used to fabricate such composites to overcome these challenges. In this study, tensile samples of tri-material based 3D-printed (TM3DP) polymer composite of polylactic acid (PLA), polyethylene terephthalate glycol (PETG), and acrylonitrile butadiene styrene (ABS) were successfully processed using fused filament fabrication (FFF) for the first time. The composite is fabricated such that 33.333% PLA was printed first, followed by 33.333% PETG, and, in the end, 33.333% ABS so that PETG is sandwiched between PLA and ABS. The effect of FFF processing parameters on the tensile properties of the printed composites was investigated. After preliminary experiments and a literature review, infill density (ID), printing speed (PS), and layer thickness (LT) were selected as the main processing parameters. The tensile strength (TS) and tensile strain (ℇ) were selected as the outputs (responses) of this study. Tensile testing was performed after printing composite tensile samples on Instron Universal Testing Machine (5 KN). An analysis of variance (ANOVA) was also performed to check the significance of FFF process parameters. The results concluded that the selected FFF process parameters were significant in the interaction state of both tensile properties. Scanning electron microscopy (SEM) and optical microscopy were also performed, which indicated that various defects, including micropores, voids, and micro / major delamination occurred in conditions of high LT, high PS, and low ID. This resulted in a low TS of 27.1 MPa and ℇ of 0.5 mm/mm. No major defects were observed under high LT, high PS, and high ID, which resulted in the highest TS of 39.5 MPa and ℇ of 0.95. Finally, optimum conditions were suggested for fabricating the thick TM3DP composite samples, believed to enhance the TS-to-mass ratio by 16.4% compared to the single solid 3D-printed base materials.

Due to the ever-increasing demand for higher production rates and the shortage of skilled labor in small industries, material handling and sorting have become extremely tedious and challenging. Industrial automation-led effective material-handling solutions like robotic arms have gained immense importance as they provide an alternative to human involvement, contribute to higher sorting accuracy, and provide enhanced safety. However, the adaptability of these robotic arms in small manufacturing industries in Pakistan is mainly hindered due to their higher costs and concerns with their structural durability. This paper presents the development of a low-cost 5-DOF robotic arm with a designed payload limit of 1 kg and automatically sorts objects fed through a conveyer belt. Catering to the compact sizing, high strength, and lower payload requirements of small industries, aluminum was selected as the material of the robotic arm due to its superior strength-to-weight ratio while being lightweight. Arm geometry was developed using SOLIDWORKS® software, which was further processed in ANSYS® software to perform the static structural analysis of the robotic arm using Finite Element Analysis (FEA). The fine meshing of the robotic arm assembly was done using triangular elements with the total number of elements and total nodes 52134 and 89104, respectively. A single point load was applied on the end effector, and the force was kept downward with an incremental loading of 1 kg starting from 100 g. These FEA simulations show that the robotic arm can hoist considerable weight while maintaining its structural integrity and directionality. The proposed robotic arm is also well-suited for manipulating objects in tight spaces due to its compact size and customizable range of motion, making it an ideal choice for applications that require precise manipulation of light loads.

Summary: Due to Covid-19, an inevitable restructuring of higher education teaching and learning pedagogies ensuring the continuous and effective learning of students is deemed important. Despite such vitality, a prevalent disparity worldwide on the usages and gains of digital and social media integration is still noticeable. Following a Scoping Literature Review and using the Atlas.ti software for a Grounded Theory qualitative analysis, this study aims to ascertain the significance of digital and social media tools during and after the Covid-19 pandemic. The study explains the common challenges and opportunities both students and educators faced in thirty countries. Drawing on the sentiment analysis of these stakeholders, results indicate that despite the acceleration of digital education into a flexible, and student-centered didactic approach, various barriers in effectively fulfilling online learning still exist. Findings also revealed the lack of, and therefore need for, proper teaching and learning material and strategies suitable for digital education.

The aim of this study was to provide a chemical profile and determine the antioxidant and antimicrobial activity of the essential oil (EO) and lipid extracts of Thymus serpyllum L. herbal dust obtained via conventional (hydrodistillation (HD) and Soxhlet extraction (SOX)) and novel extraction techniques (supercritical fluid extraction (SFE)). In addition, a comparative analysis of the chemical profiles of the obtained EO and extracts was carried out, as well as the determination of antioxidant, antibacterial and antifungal activity of the lipid extracts. According to the aforementioned antioxidant and antimicrobial activities and the monoterpene yield and selectivity, SFE provided significant advantages compared to the traditional techniques. In addition, SFE extracts could be considered to have great potential in terms of their utilization in the pharmaceutical and cosmetic industries, as well as appropriate replacements for synthetic additives in the food industry.

The use of 3D printing in construction activities can help to reduce waste, lower energy consumption, and minimize the environmental impact of building projects. As technology continues to advance, it has the potential to play a major role in the development of cleaner, more sustainable production processes in the construction industry. For each such innovation, it is essential to ensure its environmental sustainability at an early stage of development. This study aims to assess the potential environmental advantages and disadvantages of newly developed construction and demolition waste (CDW)-based geopolymer materials for 3D printing of built-environment structures. The study identifies potential ''hot spots'' of the developed process where environmental impact is highest and develops strategies to reduce or mitigate negative impacts. Life Cycle Assessment (LCA) was carried out for three cases of CDW-based 3D printed structures, Portland cement-based 3D printed structures, and conventional masonry construction methods and materials, to analyze the environmental impact of CDW-based 3D-printed designs and their comparative analysis. The results showed that geopolymer-based 3D printed construction resulted in the lowest global warming potential of 488 [kg CO2 eq] as compared to 595.6 [kg CO2 eq] for ordinary Portland cement-based structure and 533.7 [kg CO2 eq] for conventional masonry construction of the equivalent structure. The main environmental ''hot spot'' identified for the geopolymer-based 3D printed construction process was the amount of electrical energy required for the mechanical processing of waste materials, which was more than 61% of the total GWP impact. In addition to decreasing solid CDW, the developed approach has significant potential for improvement by using more sustainable energy sources and reducing the amount of solid CDW generated.

Plants in agricultural greenhouses utilize the visible spectrum for photosynthesis, while the unused solar spectrum contributes to greenhouse temperature rise in hot climates. The spectra-managed greenhouses employ innovative techniques to mitigate the cooling load by means of solar spectrum filtering. This study aims to conduct a comprehensive comparative life cycle assessment (LCA) of conventional and spectra-managed greenhouses specifically designed for hot and arid climates. The novel roof greenhouse integrates photovoltaics and dielectric mirrors for solar spectrum optimization, while the nanofluid roof greenhouse uses spectrum-selective nanofluid for sustainable cooling. The LCA evaluates the environmental impacts of greenhouse components and processes, identifying the hot spots for environmental performance improvement at the early stage of development. The life cycle impact assessment (using TRACI approach) showed that novel roof greenhouse could reduce global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), smog formation potential (SFP), and fossil fuel depletion (FFD) by 52.4%, 47.7%, 49.8%, 53.2%, and 57.4%, respectively, compared to the conventional greenhouse. Electricity is a significant contributor to environmental emissions for all analyzed greenhouses; therefore, a sensitivity analysis is performed by varying the source of electricity. For photovoltaic-generated electricity to power the greenhouses, the implementation of a nanofluid roof greenhouse resulted in a 5.1% and 23.1% reduction in GWP compared to novel roof and conventional greenhouses, respectively.

Background: In patients with essential hypertension, fragmented QRS has been associated with many remodeling components that might lead to adverse cardiovascular effects. This study aimed to evaluate the relationship between fragmented QRS and adverse events and its potential long-term prognostic value. Methods: The patients with essential hypertension were divided into two groups accord- ing to the presence of fragmented QRS: fragmented QRS (+) and fragmented QRS (−). During long-term follow-up, the relationship of fragmented QRS to coronary artery dis-ease, congestive heart failure, stroke, cardiovascular death, all-cause death, and major adverse cardiovascular and cerebrovascular events was evaluated. Results: The study group included 542 patients with essential hypertension. Fragmented QRS on ECG was observed in 224 (41.3%) patients. Considering the incidence rates at the end of 5.6 +- 1.3 years' follow-up, the total incidence rate of major adverse cardiovascular and cerebrovascular events (P

With the continuous trend of miniaturization in the electronics sector, high heat flux management is becoming increasingly important for ensuring efficient and safe operation. For thermal management of high heat flux devices, nucleate boiling is a prominent passive heat transfer approach. The two fundamental variables that can be varied to improve the effectiveness and capacity of the nucleate boiling process are the working fluid and surface properties such as surface roughness, wettability, area, and capillary. Boiling-induced interconnected porous network of silver nanowires coating is identified in this research as an efficient coating for enhanced nucleate boiling performance. The maximal ability of heat transmission, known as critical heat flux, and the efficiency of the boiling heat transfer process, represented by the heat transfer coefficient, are explored for the newly developed surfaces. Using a nucleate boiling testing setup, three distinct concentrations of silver nanowires-based nanofluids, 0.01%, 0.001%, and 0.0001%, were examined as working fluid. The working fluid resulted in the deposition of the nanowires over the heating surface and resulted in enhanced heat transfer performance. The maximum enhancement of 200% and 93.7% has been reported for critical heat flux and heat transfer coefficient, compared to deionized liquid on the unmodified Cu substrate. A detailed characterization has been performed to investigate the topology, wettability and morphology of the surfaces and understand the enhancement mechanisms.

The optimum selection of process parameters, materials, and product design is essential to achieve the desired response of 3D-printed structures, especially in functional components. The current practices of the experimental optimization process require significant resources, which can be limited through numerical modeling and simulation techniques. In this study, a thermomechanical numerical model is used to predict the performance of the additive manufacturing (AM) process, i.e., fused filament fabrication (FFF). 3D printing (3DP) process simulations were performed for tensile testing coupons using carbon fiber-reinforced polyamide-6 (PA6-CF) material. The numerical model predicted the effect of infill patterns and densities on the deflections and distortions during the FFF process. The numerical model predictions were validated via experiments performed under similar conditions. The results conclude that the numerical model can adequately predict the process-induced deflections and distortions during the FFF process. Generally, higher dimensional control was observed for rectangular infill patterns and increased infill density. However, the numerical model overestimates the shrinkage as the stress-relaxation effect is not considered in the numerical model and underestimates the warpages as perfect build plate adhesion is assumed.

The aim of this study was to determine the changes in free fatty acids and amino acids during storage of synbiotic microcapsule-added goat cheeses and determine the effect of microencapsulation on these changes during storage. Another objective was also to determine the effects of probiotics and synbiotics (probiotic + prebiotics) added in free form during the production of white goat cheese on amino acid and fatty acid values. In the study, three types of microcapsules including probiotic bacteria (Lacticaseibacillus casei and Bifidobacterium longum), probiotic + fructooligosaccharide (FOS), and probiotic + inulin containing microcapsules were prepared and cheeses were produced using these microcapsules. Cheese samples were stored at +4 °C for 180 days and the amino acids and free fatty acid content of the cheeses were determined during the storage period. The saturated fatty acid with the highest ratio in goat cheeses was palmitic acid (C16) whereas the unsaturated fatty acid with the highest ratio was determined as oleic acid (C18:1). At the end of ripening, the amino acid with the highest amount was glutamic acid in cheese samples, followed by leucine, proline, aspartic acid, and lysine, respectively. It has been determined that inoculation of probiotic cultures, either in free or microencapsulated form, into cheese milk positively influences the total amino acid and fatty acid levels. The addition of inulin along with probiotics on the 180th day of storage was effective in amino acid formation compared to cheeses with free FOS added. It could also be concluded that the addition of free or microencapsulated FOS was effective in the formation of free fatty acids. In addition, regardless of the used form (free or microcapsules), inulin was more effective in amino acid formation.

The oil and gas sector produces a substantial volume of emissions mainly generated from flaring, which adds to the total energy loss in oil and gas plants and significantly impacts air quality. Therefore, reducing and recovering flare gas is essential since it benefits economic efficiency and environmental protection objectives. Several options have been developed for flare gas recovery. One of the promising approaches is integrating solid oxide fuel cells (SOFCs) into natural gas operations. The integration of SOFCs with a flare system in a natural gas processing plant that produces two billion standard cubic feet of natural gas daily reduces the emissions and generates electricity using the complimentary fuel.Moreover, by maintaining the flame’s heating value at the flare tip to ensure the plant’s safety requirement, 70% of the flare gas can be fed to SOFC as fuel. In an on-shore plant, SOFCs are fueled by 3.5 million standard cubic feet of purge gas, which will reduce the CO2 eq. per day from 263 tons to 101 tons and generates 20 MW of electricity. For the off-shore plant, the fuel for SOFCs is around 105 thousand standard cubic feet of purge gas, which reduces the CO2 eq. per day from 9 tons to 3 tons and generates 600 kW of electricity. Utilizing SOFCs in the natural gas flare system will generate extra electricity using waste gases and reduces greenhouse gas emissions.

The trending methodology in 3DCP is accompanied by extensive trial and error methods, leading to the final product's more expensive and time-consuming development. The specific printable combination of design, materials properties, and process parameters for successful 3D concrete printing (3DCP) process resembles a “secret recipe”. This study explores the design capabilities of numerical tools for 3DCP, understands its limitations and challenges, and provides an overview for future research direction. Different analytical and numerical models have been developed in the literature as a function of material properties, printing parameters, and the geometry of the final printed structures. These models serve to optimize the printing parameters and predict the performance of the printed product and rheological responses, hence, offering a safer and more economical solution. The analytical models provide the first-degree approximation and can be used for simple shapes such as straight or tilted walls; however, numerical methods are needed for more complex structures. The literature review shows an apparent delay in the progress of computational technology to catch the pace of interest of the construction industry in 3DCP. The prediction of 3DCP structure performance is not straightforward for complex geometries, variable process parameters, or multi-materials printing. Due to involving multi-physics phenomena at each sub process, the developed numerical models are limited to a specific sub-process range. The study presents a plan to integrate different sub-processes to build a single computational model from material mixing to final buildability.

The aim of this study was to investigate the response of different doses of lipopolysaccharide (LPS) and extracellular product (ECP) antigens (25, 50, 100, 250, and 500 µg) obtained from Flavobacterium psychrophilum to changes in oxidative stress parameters (catalase [CAT], superoxide dismutase [SOD], glutathione peroxidase [GPx], glucose 6-phosphate dehydrogenase [G6PD], glutathione reductase [GR], and malondialdehyde [MDA]) in juvenile rainbow trout. For this purpose, 6 different doses of F. psychrophilum (102–106) were applied to the fish, and the lethal dose 50 % (LD50) value was determined as 1.33·104. Changes in MDA levels and antioxidant enzymes were determined by applying 25 % of the LD50 value to fish for 14 days. Accordingly, while F. psychrophilum increased GR, G6PD, GPx, and SOD activity, it decreased MDA levels and CAT activity. Initially, 25, 50, 100, 250, and 500 µg doses of ECP and LPS were applied to the fish; after 21 days, a 25 % dose of LD50 was applied to these fish. Fourteen days later, the fish were taken, and the changes in MDA levels and antioxidant enzymes were examined. As a result, it was determined that while ECP and LPS application decreased GR, G6PD, GPx, and SOD activity, there was an increase in MDA levels and CAT activity.

Lithium (Li) is primarily found in mineral resources, brines, and seawater. Extraction of Li from mineral ore deposits is expensive and energy-intensive. Li-ion batteries (LIBs) are certainly one of the important alternatives to lessen the dependence on fossil fuel resources. The global demand for LIBs for portable electrical and electronic equipment (EEE) and EVs have increased significantly, and the amount of spent LIBs (S-LIBs) is rising logarithmically. S-LIBs contain both hazardous heavy metals and toxic organic chemicals that create a serious threat to human health and the ecosystem. The current position requires the recycling of S-LIBs indispensable for the protection of the environment and the recycling of scarce raw materials from economic aspects. In this manuscript, recent developments and state-of-the-art technologies for LIB recycling were focused on and reviewed comprehensively. Pretreatment methods (such as discharging, dismantling, cathode active material (CAM) removal, binder elimination methods, classification, and separation) for S-LIBs are introduced, and all available and novel technologies that are used in different physical and chemical recovery processes are summarized and compared. The pretreatment process in LIB recycling can both improve the recovery rate of the valuable components and significantly lessen the subsequent energy consumption. Notably, pretreatment, metal extraction, and product preparation stages play vital roles in all LIB recovery processes, based on pyrometallurgy, hydrometallurgy, biometallurgy, direct recycling, and mechanical treatment and water leaching. The main goal of this review is to address the novel S-LIB materials’ current recycling research status and innovations for integrated, eco-friendly, economic, low carbon, and clean energy technologies. In the end, different industrial recycling processes are compared, existing challenges are identified and suggestions and perspectives for future LIBs recycling applications are highlighted.

Polymer nanocomposites have attracted increasing interest in research and development with several current and potential industrial applications due to their wide margin of superiority over conventional materials. Polymer composites provide a higher strength-to-weight ratio, easily customizable product properties, flexible manufacturing processes, high resistance to corrosion or erosion, and lower cost. The recent progress in additive manufacturing (AM) methods has paved the way for even a broader range of flexibilities in design and materials in several industrial sectors, including aerospace, biomedical, construction, electronics, telecommunication, mechanical, and defense. However, some hindrances remain in the synthesis of polymer composites and their fabrication through AM technologies. A comparative review of AM processes for polymer composites and their applications is presented in this study. This study aims to provide engineers and scientists with an updated understanding of the underlying issues, barriers, limitations, and opportunities. It will also help the reader to systematically reveal the research problems and future directions related to materials synthesis and AM processes.

Due to an increasing trend of size diminution, integration, and multifunctionality, the heat load on electronic devices is constantly increasing. Though nucleate boiling is regarded to be the most efficient mode of heat transfer, it still has much room for improvement in terms of heat transfer coefficient and critical heat flux. Thus, extensive research efforts have been devoted to the preparation of functional heating surfaces for enhanced boiling. This study presents nucleate boiling enhancement on a 3D porous graphene oxide/silver nanowire hybrid film. Then, boiling experiments were conducted under atmospheric pressure using a custom-developed boiling apparatus with a flat copper heating surface. Bubble-induced graphene oxide/silver nanowire hybrid deposition structures were analyzed through a series of characterizations such as Field Emission Scanning Electron Microscopy, Energy Dispersive X-Ray Spectroscopy, profilometry, and contact angle analysis to elaborate the physical mechanism behind the nucleate boiling enhancement. Among three tested concentration ratios (GO:AgNW; 0:1, 1:1, 1:5 by weight), maximum heat transfer coefficient and critical heat flux enhancement were achieved at a GO:AgNW concentration ratio of 1:5 owing to the improved surface characteristics such as surface area, bubble nucleation site density, lateral heat conduction, and capillarity. Heat transfer coefficient and critical heat flux enhancements of graphene oxide/silver nanowire hybrid surface reached 196.6% and 182.4%, while the upgrades on graphene oxide surface were 112.4% and 135.3%, respectively.

This study performs a life cycle assessment (LCA) on a novel process to produce geopolymer binders for 3-dimensional additive manufacturing (3D-AM). The method utilises construction and demolition waste (CDW) [hollow brick (HB), red clay brick (RCB), roof tile (RT), and glass (G)] as a sustainable resource for geopolymers production to replace Portland cement. The life cycle assessment is performed to identify hotspots (relevant processes or raw material) to improve the environmental performance of the whole process at an early stage of development and to evaluate the environmental impacts of energy, water, and waste emissions at various points in the life cycle. The CDW requires crushing, milling/grinding, and mixing with electrical input to produce the geopolymer binders. The alkali activators' composition [6.25M NaOH, 10% Ca(OH)2] is selected as the base case for the assessment. The life cycle impact assessment (LCIA) results show the environmental impacts to be 635 (kg CO2 eq.), 5.06 (kg SO2 eq.), 0.104 (kg N eq.), 3.14E-10 (kg N eq.), and 12.2 (CTUe.) for the global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), ozone layer depletion potential (ODP), and Ecotox air respectively for 1 m3 of geopolymer binder produced. Electricity contributes over 60% to the GWP, AP, EP, and Ecotox Air; therefore, a sensitivity analysis is performed with varying sources of renewable electricity. Also, compared to ordinary Portland cement (OPC), the GWP for the geopolymer binder produced is 21% less.

This study presents preliminary findings on the performance of the stimuli-responsive PLA/α-Fe2O3 nanocomposites under the magnetic stimulus with varying concentrations of hematite (α-Fe2O3) nanoparticles. The effect of varying nanoparticle concentrations on the structural and thermal properties was examined using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Subsequently, the magnetic field with various intensities was generated using a vibrating sample magnetometer in a controlled environment. The resulting deformation rate of the nanocomposites was observed in response to changing magnetic fields. The results revealed that the PLA/α-Fe2O3 nanocomposites could be potential materials for biomedical applications, i.e., cardiovascular stents, which can provide the desired stimulus to treat post-stenting complications without the need for secondary surgical procedures. In future studies, the synthesized PLA/α-Fe2O3 nanocomposites will be adopted for 3D printing (3DP) processes to develop patient-specific cardiovascular stents and to evaluate their biomechanical performance.

This paper consists of a life cycle assessment (LCA) analysis on an experimental study to produce recycled brick waste (RBW) and recycled ceramic tile (RCT) based geopolymers. The LCA analysis is done following ISO 14040 standards on GaBi software for geopolymers produced with different ingredients ratios and curing types/regimes. The binary geopolymer comes from RBW + RCT (Phase I) as aluminosilicate sources and alkaline solutions. The ternary geopolymer (Phase II) studied includes Class C Fly ash (FC) in addition to the RBW + RCT. And finally, for Phase III, the binary geopolymer is cured at 100 °C. The life cycle impact assessment (LCIA) methodology using TRACI 2.0 and the GaBi databases is used to calculate the following impact categories: Global Warming Potential (GWP), Acidification Potential (AP), Eutrophication Potential (EP), Ozone Depletion Potential (ODP) and smog. The LCA analysis is also modelled on a large-scale industrial basis. This results in decreased environmental impacts, and they are 1352 kg CO2-eq, 3.01 kg SO2-eq, 0.19 kg N-eq, 6.56E-9 kg CFC 1-eq for GWP, AP, EP, and ODP, respectively.

Objective:Rheumatic heart disease is the deposition of immune complexes which cause malfunction of the heart valves. Percutaneous mitral balloon valvuloplasty (PMBV) is an established treatment option in patients with symptomatic moderate or severe rheumatic mitral valve disease, but PMBV is not a preferred option in mitral stenosis (MS) patients with moderate mitral regurgitation (MR) due to the risk of severe MR. The aim of this study was to evaluate the safety and feasibility of PMBV in symptomatic MS patients with moderate MR by comparing the post-procedural parameters with those of MS patients with mild or no MR.Method:Among 104 patients with symptomatic MS, 10 patients with moderate MR were classified as group 2 while 94 patients who had mild or none MR were classified as group 1 in the present work. All patients underwent PMBV and pre- and post-procedural mitral valve area, MRs were recorded and cardiovascular events and complications were assessed in 30 days.Results:The only difference in both groups before and after the procedure was the severity of the MR. Cardiovascular death was not observed for both groups in 30 days. In group 1, there were 3 patients and in group 2, there was 1 patient who developed severe MR after PMBV. All patients who had post-procedural severe MR required mitral valve replacement in 30 days due to severe MR in group 1. The composite complication rate was similar between the groups.Conclusion:PMBV might be an alternative treatment option for selected patients having significant MS with moderate MR.

Synthetic grafting needs improvements to eliminate secondary surgeries for the removal of implants after healing of the defected tissues. Tissue scaffolds are engineered to serve as temporary templates, which support the affected tissue and gradually degrade through the healing period. Beside mechanical function to withstand the anatomic loading conditions, scaffolds should also provide a decent biological function for the diffusion of nutrients and oxygen to the cells, and excretion of the wastes from the cells to promote the new tissue growth and vascularization. Moreover, the degradation byproducts of the scaffolds should be safe to the human body. Development of such multifunctional scaffolds requires selection of the right material, design, and manufacturing method. Mg has been recognized as the prominent biodegradable metal with regards to its mechanical properties matching to that of human bone, degradability in the body fluid, and its ability to stimulate new tissue growth. Scaffolds with intricate porous structures can be designed according to the patient-specific anatomic data using computer aided designs. Additive manufacturing (AM) is the right method to materialize these models rapidly with reasonably acceptable range of dimensional accuracy. Thus, the recent research trend is to develop ideal scaffolds using biodegradable Mg through AM methods. This review compiles and discusses the available literature on the AM of biodegradable Mg parts from the viewpoints of material compositions, process conditions, formation quality, dimensional accuracy, microstructure, biodegradation, and mechanical properties. The current achievements are summarized together, and future research directions are identified to promote clinical applications of biodegradable Mg through the advancement of AM.

In this study, the in vitro effects of some metal ions (Ag+, Cd2+, Cu2+, Fe2+, Ni2+ and Pb2+) on freshwater fish Capoeta umbla liver and gill glucose 6-phosphate dehydrogenase (G6PD) have been investigated. For this purpose, C. umbla liver and gill G6PD enzymes were purified, with a specific activity of 31.52 and 22.83 EU/mg protein, 3353.2 and 736.5 fold in a yield of 19.28% and 23.15%, respectively. In order to control the enzyme purification SDS-PAGE showed a single band for the enzyme. In addition, in vitro effects of metal ions on enzyme activity were researched. As a result, Ag+, Cd2+, Cu2+, Ni2+ and Pb2+ inhibited fish liver G6PD; Ag+, Cd2+, Fe2+, Ni2+ and Pb2+ inhibited fish gill G6PD. Besides, it was found that the most effective inhibitor of G6PD enzyme within metal ions used was Ag+. Our results also demonstrate that these metals might be dangerous at low micromolar concentrations for fish G6PD enzyme.