SupraCells: Living Mammalian Cells Protected within Functional Modular Nanoparticle‐Based Exoskeletons

Creating a synthetic exoskeleton from abiotic materials to protect delicate mammalian cells and impart them with new functionalities could revolutionize fields like cell‐based sensing and create diverse new cellular phenotypes. Herein, the concept of “SupraCells,” which are living mammalian cells encapsulated and protected within functional modular nanoparticle‐based exoskeletons, is introduced. Exoskeletons are generated within seconds through immediate interparticle and cell/particle complexation that abolishes the macropinocytotic and endocytotic nanoparticle internalization pathways that occur without complexation. SupraCell formation is shown to be generalizable to wide classes of nanoparticles and various types of cells. It induces a spore‐like state, wherein cells do not replicate or spread on surfaces but are endowed with extremophile properties, for example, resistance to osmotic stress, reactive oxygen species, pH, and UV exposure, along with abiotic properties like magnetism, conductivity, and multifluorescence. Upon decomplexation cells return to their normal replicative states. SupraCells represent a new class of living hybrid materials with a broad range of functionalities.     

Fast and low complexity frequency domain analysis of nonuniform substrate integrated waveguide‐based structures

A novel, low complexity approach for the analysis of nonuniform lossy substrate‐integrated waveguide transmission lines based on the method of moments is proposed. The approach uses frequency‐dependent basis functions derived from the structure's propagation characteristics. Two tapered structures are analyzed, fabricated, and measured to validate the proposed approach. The analytical results of the proposed approach for both structures are compared to those obtained by measurement and by three‐dimensional field simulation. Excellent agreement is observed between the three sets of results with simulation time savings on more than 98% and memory requirement reduction of more than 97%.     

GPU fuzzy c-means algorithm implementations: performance analysis on medical image segmentation

Multimedia Tools and Applications - Image segmentation in the medical imagery such as MRI, is an essential step to the sensitive analysis of human tissues lesions with the objective to improve the...     

Modular Assembly of Red Blood Cell Superstructures from Metal–Organic Framework Nanoparticle-Based Building Blocks

Bio/artificial hybrid nanosystems based on biological matter and synthetic nanoparticles (NPs) remain a holy grail of materials science. Herein, inspired by the well-defined metal–organic framework (MOF) with diverse chemical diversities, the concept of “armored red blood cells” (armored RBCs) is introduced, which are native RBCs assembled within and protected by a functional exoskeleton of interlinked MOF NPs. Exoskeletons are generated within seconds through MOF NP interlocking based on metal-phenolic coordination and RBC membrane/NP complexation via hydrogen-bonding interactions at the cellular interface. Armored RBC formation is shown to be generalizable to many classes of MOF NPs or any NPs that can be coated by MOF. Moreover, it is found that armored RBCs preserve the original properties of RBCs (such as oxygen carrier capability and good ex ovo/in vivo circulation property) and show enhanced resistance against external stressors (like osmotic pressure, detergent, toxic NPs, and freezing conditions). By modifying the physicochemical properties of MOF NPs, armored RBCs provide the capability for blood nitric oxide sensing or multimodal imaging. The synthesis of armored RBCs is straightforward, reliable, and reversible and hence, represent a new class of hybrid biomaterials with a broad range of functionalities.     

IARP: An Intelligent ACO-Based Routing Protocol with Multiple Mobile Sinks Support for Wireless Sensor Networks

Wireless Personal Communications - Using a single fixed sink in wireless sensor networks (WSNs) creates the hotspot problem. Recently, the mobile sink technique is considered as a good solution to...     

Design and simulation of pyroelectric detectors with nanometer size spider-web for low thermal conductance

We report the design and simulation of uncooled pyroelectric detectors which utilizes a nanometer sized mesh or truss to support the suspended detector. Pyroelectric detector is a class of thermal detector in which the change in temperature causes the change in the spontaneous polarization in the sensing material. Ca modified lead titanate (PCT) was selected as the thermometer in the detector because of its high pyroelectric figure of merit. The design and simulation of pyroelectric detectors have been conducted by simulating the structure with Intellisuite™. Finite element method (FEM) was used to simulate the structural and thermal properties of the device. The simulated detectors had a spider web-like structure with each of the strut (ring) of spider web had a width of 100 nm. In the design, the pyroelectric detectors utilized Ni_0.8Cr_0.2 absorber, PCT sensing layer, Ti electrodes, Al₂O₃ structural layer to obtain low thermal conductance between the detector and Si substrate. Three different types of pyroelectric detectors were designed and analyzed. The first design had linear electrode and simple spider web support. The value of the thermal conductance of this detector was found to be 3.98 × 10⁻⁸ W/K. The second design had a longer thermal path than the first one and the thermal conductivity of this device was found to be 2.41 × 10⁻⁸ W/K. High detectivity was obtained by reducing the thermal conductance between the sensing layer and the substrate or the heat sink in the third design. The design was optimized for the best result by modifying the shape, dimension and thickness of various layers namely absorber, electrodes, sensing layer, and struts. The thermal conductance between the sensor and the substrate using the third design was found to be as low as 4.57 × 10⁻⁹ W/K which is significantly lower than previously reported values. The thicknesses of the web structure, web support, electrodes, sensing layer, and absorber of the final structure were 2, 1, 0.5, 2, and 0.2 µm respectively for this value of thermal conductance. The absorber diameter was 50 µm and the diameter of the spider web was 200 µm. A total of 80 struts with 100 nm width were used in the design.

     

CRAN,H‐CRAN,and F‐RAN for 5G systems: Key capabilities and recent advances

The world of telecommunication is witnessing a swift metamorphosis towards fifth generation cellular networks. Particularly, the rapid shift from a user centric to a device centric communication has created a tremendous impact on service complexity and network requirements. The future networks present requisite needs in ubiquitous throughput, low latency, and high reliability. They are also envisioned to provide energy efficiency, spectrum reuse, network scalability, and robustness as well as improved quality of user experience, which proves to be of ultimate importance. Accordingly, government, academic, and industrial institutions are working together to fulfill these challenging goals. Their research efforts have been extensively reported in various topics and directions, such as heterogeneous small cell networks, millimeter wave communication, massive multiple input multiple output, network function virtualization, software‐defined network, and device‐to‐device communication. More interestingly, a revolutionary network architecture based on cloud computing and centralized processing is adopted as one of the best candidates for fifth generation. It is denoted Cloud Radio Access Network (CRAN) and (H‐CRAN) in heterogeneous networks. An upgraded version, namely, Fog RAN (F‐RAN), with caching and fog computing capabilities is also presented. Environmental friendly, it ensures flexibility and scalability with reduced expenditures. This paper presents the aforementioned key technological functionalities and surveys the benefits and challenges of CRAN, H‐CRAN, and F‐RAN.     

Tensile Properties and Fusion Zone Hardening for GMAW and MIEA Welds of a 7075-T651 Aluminum Alloy

Tensile and hardness values for 7075-T651 aluminum alloy in the as welded and post weld heat treated conditions（solubilization and artificial aging-T6）,obtained using GMAW and modified indirect electric arc（MIEA）welding processes are presented.Results showed that the base material along rolling direction exhibited a tensile strength of around 600 MPa and elongation of 11%.For the as welded condition,tensile strength was 260 MPa and elongation percent of 3%.This behavior was attributed to brittleness induced by the microstructural characteristics of the welded alloys,as well as high porosity.Hardness profiles along the welds were obtained and different welded zones were identified.A soft zone（＊100 HV0.1） in the heat affected zone for GMAW and MIEA was observed,the minimum hardness corresponding to weld metal（＊85 and ＊96 HV0.1for GMAW and MIEA,respectively）.The high dilution between filler and base metal during welding in MIEA allows to the Zn and Cu to flow from the base metal into the weld metal,inducing hardening by solution and subsequent artificial aging.In this regard,the hardness of the weld metal for MIEA increases by 56%,while the tensile strength reaches a value close to 400 MPa.For GMAW,non-favorable hardening effect was observed for the weld metal after solution and artificial aging.     

Erythrocyte Toxicities of Imidazolidinyl Urea and Diazolidinyl Urea

The addition of antimicrobial preservatives to pharmaceutical and cosmetic products is necessary to prevent microbial growth. However, the use of preservatives can also produce other undesirable effects. For several years, researchers have been investigating the use of alternative methods in safety assessment of cosmetic ingredients and formulations by means of variety methods. The aim of this study was to evaluate the erythrocyte toxicities of two commercial preservatives： imidazolidinyl urea and diazolidinyl urea. Relatively few studies about the cytotoxicity of these preservative are available. The determination of their cytotoxicity is an essential step to warrant their safe use. Erythrocyte toxicities were evaluated by assessment of the amount of hemoglobin released by red blood cells after their lysis. In this study, both imidazolidinyl urea and diazolidinyl urea showed cytotoxic activity against red blood cells. The imidazolidinyl urea induce a small release of hemoglobin after 120 min of incubation. But, the diazolidinyl urea induce a massive release of hemoglobin from the imidazolidinyl urea （a rate of 83% at concentrations of 6.25 mg/mL and 12.5 mg/mL）.