Printability disparities in heterogeneous material combinations via laser directed energy deposition:a comparative study

Additive manufacturing provides achievability for the fabrication of bimetallic and multi-material structures;however,the material compatibility and bondability directly affect the parts’formability and final quality.It is essential to understand the underlying printability of different material combinations based on an adapted process.Here,the printability disparities of two common and attractive material combinations(nickel-and iron-based alloys)are evaluated at the macro and micro levels via laser directed energy deposition(DED).The deposition processes were captured using in situ high-speed imaging,and the dissimilarities in melt pool features and track morphology were quantitatively investigated within specific process windows.Moreover,the microstructure diversity of the tracks and blocks processed with varied material pairs was comparatively elaborated and,complemented with the informative multi-physics modeling,the presented non-uniformity in mechanical properties(microhardness)among the heterogeneous material pairs was rationalized.The differences in melt flow induced by the unlike thermophysical properties of the material pairs and the resulting element intermixing and localized re-alloying during solidification dominate the presented dissimilarity in printability among the material combinations.This work provides an in-depth understanding of the phenomenological differences in the deposition of dissimilar materials and aims to guide more reliable DED forming of bimetallic parts.

Diabetes and cancer:Looking at the multiligand/RAGE axis

The association between diabetes and hyperglycemia and the associated increased risk of several solid and hematologic malignancies has been the subject of investigation for many years.Although the association is not fully understood,current knowledge clearly indicates that diabetes may influence malignant cell transformation by several mechanisms,including hyperinsulinemia,hyperglycemia and chronic inflammation.In this context,the receptor for advanced glycation end-products (RAGE) has emerged as a focal point in its contribution to malignant transformation and tumor growth.We high-light how RAGE,once activated,as it manifests itself in conditions such as diabetes or hyperglycemia,is able to continuously bring about an inflammatory milieu,thus supporting the contribution of chronic inflammation to the development of malignancies.

Porous metal implants: processing,properties, and challenges

Porous and functionally graded materials have seen extensive applications in modern biomedical devices—allowing for improved site-specific performance;their appreciable mechanical,corrosive,and biocompatible properties are highly sought after for lightweight and high-strength load-bearing orthopedic and dental implants.Examples of such porous materials are metals,ceramics,and polymers.Although,easy to manufacture and lightweight,porous polymers do not inherently exhibit the required mechanical strength for hard tissue repair or replacement.Alternatively,porous ceramics are brittle and do not possess the required fatigue resistance.On the other hand,porous biocompatible metals have shown tailorable strength,fatigue resistance,and toughness.Thereby,a significant interest in investigating the manufacturing challenges of porous metals has taken place in recent years.Past research has shown that once the advantages of porous metallic structures in the orthopedic implant industry have been realized,their biological and biomechanical compatibility—with the host bone—has been followed up with extensive methodical research.Various manufacturing methods for porous or functionally graded metals are discussed and compared in this review,specifically,how the manufacturing process influences microstructure,graded composition,porosity,biocompatibility,and mechanical properties.Most of the studies discussed in this review are related to porous structures for bone implant applications;however,the understanding of these investigations may also be extended to other devices beyond the biomedical field.

RAGE at Tumor Microenvironment. Looking at Tumor-associated Macrophages

A compelling body of evidence has demonstrated that activation of the receptor for advanced glycation endproducts(RAGE)is responsible for triggering an inflammatory response and being associated with many clinical entities,including diabetes,neurodegerative diseases,cardiovascular diseases and cancer^([1-4]).

Identification of genomic features associated with immunotherapy response in gastrointestinal cancers

Gastrointestinal(GI) cancers prevail and account for an extremely high number of cancer deaths worldwide. The traditional treatment strategies, including surgery, chemotherapy, radiotherapy, and targeted therapy, have a limited therapeutic effect for advanced GI cancers. Recently, immunotherapy has shown promise in treating various refractory malignancies, including the GI cancers with mismatch repair deficiency(dMMR) or microsatellite instability(MSI). Thus,immunotherapy could be a promising treatment approach for GI cancers.Unfortunately, only a small proportion of GI cancer patients currently respond to immunotherapy. Therefore, it is important to discover predictive biomarkers for stratifying GI cancer patients response to immunotherapy. Certain genomic features, such as dMMR/MSI, tumor mutation burden(TMB), and tumor aneuploidy have been associated with tumor immunity and im-munotherapy response and may serve as predictive biomarkers for cancer immunotherapy. In this review, we examined the correlations between tumor immunity and three genomic features: dMMR/MSI, TMB, and tumor aneuploidy. We also explored their correlations using The Cancer Genome Atlas data and confirmed that the dMMR/MSI status, high TMB, and low tumor aneuploidy are associated with elevated tumor immunity in GI cancers. To improve the immunotherapeutic potential in GI cancers, more genetic or genomic features associated with tumor immune response need to be identified. Furthermore, it is worth exploring the combination of different immunotherapeutic methods and the combination of immunotherapy with other therapeutic approaches for cancer therapy.

Diabetes mellitus contribution to the remodeling of the tumor microenvironment in gastric cancer

Compelling pieces of evidence derived from both clinical and experimental research has demonstrated the crucial contribution of diabetes mellitus(DM)as a risk factor associated with increased cancer incidence and mortality in many human neoplasms,including gastric cancer(GC).DM is considered a systemic inflammatory disease and therefore,this inflammatory status may have profound effects on the tumor microenvironment(TME),particularly by driving many molecular mechanisms to generate a more aggressive TME.DM is an active driver in the modification of the behavior of many cell components of the TME as well as altering the mechanical properties of the extracellular matrix(ECM),leading to an increased ECM stiffening.Additionally,DM can alter many cellular signaling mechanisms and thus favoring tumor growth,invasion,and metastatic potential,as well as key elements in regulating cellular functions and cross-talks,such as the microRNAs network,the production,and cargo of exosomes,the metabolism of cell stroma and resistance to hypoxia.In the present review,we intend to highlight the mechanistic contributions of DM to the remodeling of TME in GC.

Dynamics Study and Analysis of Laser-Induced Transport of Nanoferrofluid in Water Using Fluorescein Isothiocyanate (FITC) as Fluorescence Marker

FITC-conjugated nanoferrofluid (FNFF) was synthesized and characterized to study the dynamic of laser-induced transport of NPs in water. The results confirmed a definite laser-induced enhanced velocity of NPs (100 μm⋅s−1) almost twice as much the without laser (i.e. Brownian motion). The diffusion coefficients of 17 × 10−6 m2⋅s−1 and 55 × 10−6 m2⋅s−1 were found for the cases without and with laser action respectively. The act of laser when switched on after NPs had reached the steady state was very prominent. The laser-induced heat and power generated by NPs were calculated 0.2μW⋅cm−3 and 0.4 pW⋅cm−2 respectively. Our experiment condition was non-adiabatic and that the heat generated was diffused into the surrounding. We considered the Maxwell’s criteria (Kp/Kw −1⋅K−1. Based on the Brownian diffusion and DLVO theory, at earlier times where the NPs are more dispersed within the medium are displaced faster. However, at later stages they become less mobile as they are agglomerated. The mechanisms for the enhanced mobility and laser transport of NPs are thought to be due to e.m.w induced force (i.e. an oscillatory motion) and laser absorptive force (i.e., photothermophoresis). A beam divergence of about 5.24°(or 91 mrad) was determined. A non-linear behaviour of laser beam was observed as a trajectory path within the water due to thermal heating hence causing the change of refractive index of medium and redistribution of NPs concentration.

Advanced-glycation end-products axis:A contributor to the risk of severe illness from COVID-19 in diabetes patients

Compelling pieces of evidence derived from both clinical and experimental research has demonstrated the crucial role of the receptor for advanced-glycation end-products(RAGE)in orchestrating a plethora of proinflammatory cellular responses leading to many of the complications and end-organ damages reported in patients with diabetes mellitus(DM).During the coronavirus disease 2019(COVID-19)pandemic,many clinical reports have pointed out that DM increases the risk of COVID-19 complications,hospitalization requirements,as well as the overall severe acute respiratory syndrome coronavirus 2 case-fatality rate.In the present review,we intend to focus on how the basal activation state of the RAGE axis in common preexisting conditions in DM patients such as endothelial dysfunction and hyperglycemia-related prothrombotic phenotype,as well as the contribution of RAGE signaling in lung inflammation,may then lead to the increased mortality risk of COVID-19 in these patients.Additionally,the crosstalk between the RAGE axis with either another severe acute respiratory syndrome coronavirus 2 receptor molecule different of angiotensin-converting enzyme 2 or the renin-angiotensin system imbalance produced by viral infection,as well as the role of this multi-ligand receptor on the obesity-associated lowgrade inflammation in the higher risk for severe illness reported in diabetes patients with COVID-19,are also discussed.

Effect of Temperature on Optical Properties of Vegetable Oils Using UV-Vis and Laser Fluorescence Spectroscopy

UV-Vis absorption and fluorescence spectroscopy are used to test the quality and changes in the composition of extra virgin olive oil (EVOO) and canola oil (CO) with temperature. The increase of temperature caused a change in the molecular structures of both types of oils seen as a gradual decrease of intensity amplitudes of absorption and fluorescence signals. A significant alteration occurred at ≈200&#176C where almost the main spectra of pheophytin-a, b, carotenoids, lutein and vitamin E in EVOO and linoleic acid and oleic acid in CO disappeared. An independent experiment showed the output of laser changes linearly with the input in oil at constant temperature (i.e., room temperature) where the transmission values of ≈33% and ≈75% are determined for EVOO and CO respectively. However, the transmission through a heated oil exhibited a non-linear behaviour which indicates the molecular optical response to thermal changes. The effect of storage time and adulteration of oils were also evaluated.

Crystallinity of FRCM/GPM with High PB through Microbial Growth

Fiber reinforced composite (FRC) requires a process of grinding, mixing and compounding natural fibers from cellulosic waste streams into a polymer matrix that creates a high-strength fiber composite. In this situation, the specified waste or base raw materials used are the waste thermoplastics and different types of cellulosic waste including rice husk and saw dust. FRC is a high-performance fiber composite achieved and made possible through a proprietary molecular re-engineering process by interlinking cellulosic fiber molecules with resins in the FRC material matrix, resulting in a product of exceptional structural properties. In this feat of molecular re-engineering, selected physical and structural properties of wood are effectively cloned and obtained in the FRC component, in addition to other essential qualities in order to produce superior performance properties to conventional wood. The dynamic characteristics of composite structures are largely extracted from the reinforcing of fibres. The fiber, held in place by the matrix resin, contributes to tensile strength in a composite, enhancing the performance properties in the final part, such as strength and rigidity, while minimizing weight. The advantages of composite materials always beat down their disadvantages. In this analysis, we tried to find out FRC advance manufacturing, recycling technology and future perspective for mankind and next generation development. This research will bring a new horizon for future science with FRC technology and every aspect of modern science which will bring a stable dimensional stability by recycling process with minimizing waste for environment and next generation science.

Expression of the SARS-CoV-2 cell receptor gene ACE2 in a wide variety of human tissues

Background:Since its discovery in December 2019,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has infected more than 2180000 people worldwide and has caused more than 150000 deaths as of April 16,2020.SARS-CoV-2,which is the virus causing coronavirus disease 2019(COVID-19),uses the angiotensin-converting enzyme 2(ACE2)as a cell receptor to invade human cells.Thus,ACE2 is the key to understanding the mechanism of SARS-CoV-2 infection.This study is to investigate the ACE2 expression in various human tissues in order to provide insights into the mechanism of SARS-CoV-2 infection.Methods:We compared ACE2 expression levels across 31 normal human tissues between males and females and between younger(ages≤49 years)and older(ages>49 years)persons using two-sided Student's t test.We also investigated the correlations between ACE2 expression and immune signatures in various tissues using Pearson's correlation test.Results:ACE2 expression levels were the highest in the small intestine,testis,kidneys,heart,thyroid,and adipose tissue,and were the lowest in the blood,spleen,bone marrow,brain,blood vessels,and muscle.ACE2 showed medium expression levels in the lungs,colon,liver,bladder,and adrenal gland.ACE2 was not differentially expressed between males and females or between younger and older persons in any tissue.In the skin,digestive system,brain,and blood vessels,ACE2 expression levels were positively associated with immune signatures in both males and females.In the thyroid and lungs,ACE2 expression levels were positively and negatively associated with immune signatures in males and females,respectively,and in the lungs they had a positive and a negative correlation in the older and younger groups,respectively.Conclusions:Our data indicate that SARS-CoV-2 may infect other tissues aside from the lungs and infect persons with different sexes,ages,and races equally.The different host immune responses to SARS-CoV-2 infection may partially explain why males and females,young and old persons infected with this virus have markedly distinct disease severity.This study provides new insights into the role of ACE2 in the SARS-CoV-2 pandemic.