Three Dimensional (3D) Printable Gel-Inks for Skin Tissue Regeneration

Recent and rapid progression in three-dimensional (3D) printing techniques has revolutionized conventional therapies in medicine; 3D printed constructs are gradually being recognized as common substitutes for the replacement of skin wounds. As gel-inks, large numbers of natural and synthetic (e.g., collagen and polyurethane, respectively) substances were used to be printed into different shapes and sizes for managing both acute and chronic skin wounds. The resultant 3D printed scaffolds not only provide physical support but also act as supporting niches for improving immunomodulation and vascularization and subsequent accelerated wound healing. Recently, the use of thermosensitive and pH-responsive gels has made it possible to prepare 3D printed constructs with the ability to facilitate in situ crosslinking within the biopolymer and with native wound edge tissue as well as to fill the exact shape of wound damage. In this chapter, we aim to introduce the current state of 3D printable gel-inks utilized for skin wound treatment and illustrate future prospects in this amazing area of science

Failure Analysis of Corrosion Case Histories

Sadeq Hooshmand Zaferan

The application of finite element analysis as a new approach in corrosion and integrity assessment programs

Published: February 02, 2017Structural integrity assessment procedures are interesting areas in many industrial plants, e.g., oil and gas, and petrochemical for ensuring the safety and economy of an operating sector. The remaining strength of components (e.g. pipelines, risers) with corrosion defects is a prevalent project in the oil and gas industry, and it has been investigated for years via using experimental, numerical and analytical methods. Obtaining the stress distribution in the vicinity of corrosion defects is a decisive phase in understanding the structural integrity of corroded components under high internal pressure. In the corrosion based management programs, finite element analysis (FEA) can provide valuable results in the integrity assessment. Also, FEA can be applied to corrosion monitoring of structures by considering different parameters such as protecting current distribution, electrochemical potential grid and coating degradation. This research discusses the application of FEA in the corrosion and integrity assessment process based on three areas including, in-service performance of corroded parts, repairing methods and corrosion monitoring techniques.Sadeq Hooshmand Zaferan

Antioxidant Effects of Bioactive Glasses (BGs) and Their Significance in Tissue Engineering Strategies

Elevated levels of oxidative stress are usually observed following injuries, leading to impaired tissue repair due to oxidation-related chronic inflammation. Several attempts have been made to manage this unfavorable situation, and the use of biomaterials with antioxidant activity is showing great promise in tissue engineering and regenerative medicine approaches. Bioactive glasses (BGs) are a versatile group of inorganic substances that exhibit an outstanding regenerative capacity for both hard and soft damaged tissues. The chemical composition of BGs provides a great opportunity for imparting specific biological activities to them. On this point, BGs may easily become antioxidant substances through simple physicochemical modifications. For example, particular antioxidant elements (mostly cerium (Ce)) can be added to the basic composition of the glasses. On the other hand, grafting natural antioxidant substances (e.g., polyphenols) on the BG surface is feasible for making antioxidant substitutes with promising results in vitro. Mesoporous BGs (MBGs) were demonstrated to have unique merits compared with melt-derived BGs since they make it possible to load antioxidants and deliver them to the desired locations. However, there are actually limited in vivo experimental studies on the capability of modified BGs for scavenging free radicals (e.g., reactive oxygen species (ROS)). Therefore, more research is required to determine the actual potential of BGs in decreasing oxidative stress and subsequently improving tissue repair and regeneration. The present work aims to highlight the potential of different types of BGs in modulating oxidative stress and subsequently improving tissue healing

Microtensile bond strength of ceramic to resin using different silanes

Oral Session - Dental Materials 1: Adhesion - Bond Strength Testing and Mechanisms: 9. Cement Adhesion to Ceramics: no. 27OBJECTIVES: The purpose of this study was to assess the micro-tensile bond strength of a leucite-reinforced feldspathic ceramic to a resin cement using different types of silane primers. METHODS: 18 leucite-reinforced feldspathic ceramic blocks (Ceramco II, Dentsply) in dimensional of 6×6×6 mm were fabricated. The ceramic blocks were ground on wet SiC papers and then cleansed ultrasonically in distilled water. The bonding ceramic surfaces were treated with different silane solutions as follows: Commercial silane as control: Monobond S (Ivoclar-Vivadent); methacryloxypropyl silane and experimental silanes with two concentrations (1% and 2.5%): amino, isocyanate, styryl, and acrylate silanes. The silane application method consisted of ...postprin

The use of locus specific microsatellite markers for detecting genetic variation in hatchery bred probarbus jullieni.

This study is to demonstrated that microsatellites markers developed for Tor tambroides can be used to amplify microsatellite loci in other family. It is assumed that microsatellite loci are more conserved for aquatic species compared to terrestrial ones due to aquatic environments are less mutagenic than terrestrial ones. Development of microsatellites still requires investment of time and resources. Thus using loci already developed in a related species may provide a cost-effective alternative to microsatellite isolation and development in a species of interest in present study, Probarbus jullieni. In this study we investigated the possibility of the conservation of microsatellite flanking regions among different species. Nine pairs of SSR primers, five gave very strong banding profile (SYK1, SYK 2, SYK 5 SYK 8 and SYK 9) which could be used for population studies by using the nested protocol. Results showed that SYK 2 and SYK 9 flanked the same (CA)n repeats and thus are highly conserved in a different species. The products of the SYK 5, 8 and 1 primer pairs showed differences in the microsatellite regions which they flanked in Probarbus jullieni when compared to those of the source species, Tor tambroides. The mean observed heterozygosity levels for all the primers ranged 0.23-0.81. The primers are all polymorphic with the mean number of alleles from 2-5

Wearable Nano-Based Gas Sensors for Environmental Monitoring and Encountered Challenges in Optimization

With a rising emphasis on public safety and quality of life, there is an urgent need to ensure optimal air quality, both indoors and outdoors. Detecting toxic gaseous compounds plays a pivotal role in shaping our sustainable future. This review aims to elucidate the advancements in smart wearable (nano)sensors for monitoring harmful gaseous pollutants, such as ammonia (NH3), nitric oxide (NO), nitrous oxide (N2O), nitrogen dioxide (NO2), carbon monoxide (CO), carbon dioxide (CO2), hydrogen sulfide (H2S), sulfur dioxide (SO2), ozone (O3), hydrocarbons (CxHy), and hydrogen fluoride (HF). Differentiating this review from its predecessors, we shed light on the challenges faced in enhancing sensor performance and offer a deep dive into the evolution of sensing materials, wearable substrates, electrodes, and types of sensors. Noteworthy materials for robust detection systems encompass 2D nanostructures, carbon nanomaterials, conducting polymers, nanohybrids, and metal oxide semiconductors. A dedicated section dissects the significance of circuit integration, miniaturization, real-time sensing, repeatability, reusability, power efficiency, gas-sensitive material deposition, selectivity, sensitivity, stability, and response/recovery time, pinpointing gaps in the current knowledge and offering avenues for further research. To conclude, we provide insights and suggestions for the prospective trajectory of smart wearable nanosensors in addressing the extant challenges

Biomedical waste management by using nanophotocatalysts: The need for new options

Biomedical waste management is getting significant consideration among treatment technologies, since insufficient management can cause danger to medicinal service specialists, patients, and their environmental conditions. The improvement of waste administration protocols, plans, and policies are surveyed, despite setting up training programs on legitimate waste administration for all healthcare service staff. Most biomedical waste substances do not degrade in the environment, and may also not be thoroughly removed through treatment processes. Therefore, the long-lasting persistence of biomedical waste can effectively have adverse impact on wildlife and human beings, as well. Hence, photocatalysis is gaining increasing attention for eradication of pollutants and for improving the safety and clearness of the environment due to its great potential as a green and eco-friendly process. In this regard, nanostructured photocatalysts, in contrast to their regular counterparts, exhibit significant attributes such as non-toxicity, low cost and higher absorption efficiency in a wider range of the solar spectrum, making them the best candidate to employ for photodegradation. Due to these unique properties of nanophotocatalysts for biomedical waste management, we aim to critically evaluate various aspects of these materials in the present review and highlight their importance in healthcare service settings

Efficacy of the Biomaterials 3 wt%-nanostrontium-hydroxyapatite-enhanced Calcium Phosphate Cement (nanoSr-CPC) and nanoSr-CPC-incorporated Simvastatin-loaded Poly(lactic-co-glycolic-acid) Microspheres in Osteogenesis Improvement

Aims The purpose of this multi-phase explorative in vivo animal/surgical and in vitro multi-test experimental study was to (1) create a 3 wt%-nanostrontium hydroxyapatite-enhanced calcium phosphate cement (Sr-HA/CPC) for increasing bone formation and (2) creating a simvastatin-loaded poly(lactic-co-glycolic acid) (SIM-loaded PLGA) microspheres plus CPC composite (SIM-loaded PLGA + nanostrontium-CPC). The third goal was the extensive assessment of multiple in vitro and in vivo characteristics of the above experimental explorative products in vitro and in vivo (animal and surgical studies). Methods and results pertaining to Sr-HA/CPC Physical and chemical properties of the prepared Sr-HA/CPC were evaluated. MTT assay and alkaline phosphatase activities, and radiological and histological examinations of Sr-HA/CPC, CPC and negative control were compared. X-ray diffraction (XRD) indicated that crystallinity of the prepared cement increased by increasing the powder-to-liquid ratio. Incorporation of Sr-HA into CPC increased MTT assay (biocompatibility) and ALP activity (P \u3c 0.05). Histomorphometry showed greater bone formation after 4 weeks, after implantation of Sr-HA/CPC in 10 rats compared to implantations of CPC or empty defects in the same rats (n = 30, ANOVA P \u3c 0.05). Methods and results pertaining to SIM-loaded PLGA microspheres + nanostrontium-CPC composite After SEM assessment, the produced composite of microspheres and enhanced CPC were implanted for 8 weeks in 10 rabbits, along with positive and negative controls, enhanced CPC, and enhanced CPC plus SIM (n = 50). In the control group, only a small amount of bone had been regenerated (localized at the boundary of the defect); whereas, other groups showed new bone formation within and around the materials. A significant difference was found in the osteogenesis induced by the groups sham control (16.96 ± 1.01), bone materials (32.28 ± 4.03), nanostrontium-CPC (24.84 ± 2.6), nanostrontium-CPC-simvastatin (40.12 ± 3.29), and SIM-loaded PLGA + nanostrontium-CPC (44.8 ± 6.45) (ANOVA P \u3c 0.001). All the pairwise comparisons were significant (Tukey P \u3c 0.01), except that of nanostrontium-CPC-simvastatin and SIM-loaded PLGA + nanostrontium-CPC. This confirmed the efficacy of the SIM-loaded PLGA + nanostrontium-CPC composite, and its superiority over all materials except SIM-containing nanostrontium-CPC