A 3D LTCC-Based Ceramic Microfluidic System with RF Dielectric Heating of Liquids

The design, fabrication and functional evaluation of the radio-frequency dielectric heating of liquids in an LTCC-based ceramic microfluidic system are described and discussed. The device, which relies on the dielectric heating of liquids, was fabricated using a low temperature co-fired ceramic (LTCC) technology. A multilayered ceramic structure with integrated electrodes, buried channels and cavities in micro and millimetre scales was fabricated. The structure with the dimensions of 35 mm × 22 mm × 2.4 mm includes a buried cavity with a diameter of 17.3 mm and a volume of 0.3 mL. The top and bottom faces of the cavity consist of silver/palladium electrodes protected with 100 μm thick layers of LTCC. The power, used to heat a polar liquid (water) in the cavity with the volume of 0.3 mL, ranges from 5 to 40 W. This novel application of RF dielectric heating could enable the miniaturization of microfluidic systems in many applications. The working principle of such a device and its efficiency are demonstrated using water as the heated medium.

DESIGNING OF NANOCOMPOSITE MODEL STRUCTURE USING GLYCITEIN AND GENISTEIN WITH TWELVE DIFFERENT METAL ATOMS USING IN SILICO METHOD

Nanocomposite formulation is still in its evolving state. However due to its significant therapeutic applications it has grabbed the attention of many researchers. Isoflavonewhich is widely found in soy products have tremendous medicinal propertieswhen it interacts with nanoparticles can become a boon. Hence in this study, we are reporting the interaction properties/patterns of two ubiquitous flavones namelyGlycitein and Genistein forming a nanocomposite model with 12 different metals such as Gold, Silver, Palladium, Platinum, Ruthenium, Rhodium, Cadmium, Iron, Nickel, Zinc, Copper and Antimony based ontheir potency to form nanoparticles. To mimic the Nanocomposite, model the formulation was conducted in Avogadro Software for windows. Glycitein and Genistein create a possibility of selecting the most suitable -OH position that would serve as the binding site. On selection of the appropriate binding site the interaction amid two molecules of glycitein and genistein placed sidewise held together by above-mentioned metals also surrounded by the same metal on another vacant -OH position forming a close saturated structure subjected for interaction. Based on predominantly energy levels the least energy obtained model was Cadmium and the peak procured by Antimony making it least stable and unfavorable for the perceived result.

The Surface Photogalvanic and Photon Drag Effects in Ag/Pd Metal-Semiconductor Nanocomposite

We performed the investigation of the polarization-sensitive photocurrent generated in silver-palladium metal-semiconductor nanocomposite films under irradiation with nanosecond laser pulses at the wavelength of 2600 nm. It is shown that in both the transverse and the longitudinal configuration, the surface photogalvanic (SPGE) and photon drag effects (PDE) contribute to the observed photocurrent. However, the temporal profile of the transverse photocurrent pulse is monopolar at any polarization and angle of incidence, while the temporal profile of the longitudinal photocurrent pulse depends on the polarization of the excitation beam. Specifically, the irradiation of the film with the s-polarized excitation beam produces a monopolar photoresponse, while at p-polarized excitation, the photoresponse is bipolar, having a short front and long tail. Obtained experimental results are in agreement with the developed phenomenological theory, which describes transverse and longitudinal photocurrents due to SPGE and PDE in terms of relevant second-order nonlinear susceptibilities and allows us to obtain their dependences on the angle of incidence and polarization of the excitation laser beam. The pronounced dependence of the photocurrent on the angle of incidence and polarization of the excitation beam opens avenues toward the development of polarization- and position-sensitive detectors for industrial and space applications.

Physico-chemical Processes at the Interface of Heterostructures Ag-Pd – Sn-Pb

Physicochemical processes taking place at the interface of film elements (conductors) of hybrid integrated circuits, thick-film sensors and other microelectronic devices (MED) based on silver-palladium pastes and elements of standard soldering materials have been studied. Physicochemical mechanisms of processes of the material element mutual dissolution at the interface are proposed and analyzed. Conclusions are made that these processes affect the degradation of the electrophysical parameters and contact switch connections operational characteristics. It is established that the degradation main cause (partial or complete destruction of the contact connections on substrate ceramics (glass) Ag-Pd – Sn-Pb) is the functional film material significant dissolution in the Sn-Pb melt.

Framework Materials for Full-Arch Implant-Supported Rehabilitations: A Systematic Review of Clinical Studies

The purpose of this systematic review was to investigate the clinical outcomes of frameworks made of different materials in patients with implant-supported full-arch prostheses. A literature search was conducted on MEDLINE, Scopus and Cochrane Library, until the 1st of March 2021, with the following search terms: framework or substructure combined with “dental implants”. The outcomes evaluated were: implant and prosthesis survival, bone resorption, biological and technical complications. The Cochrane Handbook for Systematic Reviews of Interventions was employed to assess the risk of bias in randomized clinical trials. The Newcastle–Ottawa quality assessment scale was used for non-randomized studies. In total, 924 records were evaluated for title and abstract, and 11 studies were included in the review: 4 clinical randomized trials and 7 cohort studies. The framework materials investigated were: gold alloy, titanium, silver-palladium alloy, zirconia and polymers including acrylic resin and carbon-fiber-reinforced composites. High implant and prosthetic cumulative survival rates were recorded by all included studies. Various materials and different fabrication techniques are now available as alternatives to traditional cast metal frameworks, for full-arch implant-supported rehabilitations. Further long-term studies are needed to validate the use of these materials and clarify their specific clinical indications and manufacturing protocols to optimize their clinical outcomes.

Surface-bound reactive oxygen species generating nanozymes for selective antibacterial action

Acting by producing reactive oxygen species (ROS) in situ, nanozymes are promising as antimicrobials. ROS’ intrinsic inability to distinguish bacteria from mammalian cells, however, deprives nanozymes of the selectivity necessary for an ideal antimicrobial. Here we report that nanozymes that generate surface-bound ROS selectively kill bacteria over mammalian cells. This result is robust across three distinct nanozymes that universally generate surface-bound ROS, with an oxidase-like silver-palladium bimetallic alloy nanocage, AgPd0.38, being the lead model. The selectivity is attributable to both the surface-bound nature of ROS these nanozymes generate and an unexpected antidote role of endocytosis. Though surface-bound, the ROS on AgPd0.38 efficiently eliminated antibiotic-resistant bacteria and effectively delayed the onset of bacterial resistance emergence. When used as coating additives, AgPd0.38 enabled an inert substrate to inhibit biofilm formation and suppress infection-related immune responses in mouse models. This work opens an avenue toward biocompatible nanozymes and may have implication in our fight against antimicrobial resistance.