Microfluidically Assisted Synthesis of Calcium Carbonate Submicron Particles with Improved Loading Properties.

The development of advanced methods for the synthesis of nano- and microparticles in the field of biomedicine is of high interest due to a range of reasons. The current synthesis methods may have limitations in terms of efficiency, scalability, and uniformity of the particles. Here, we investigate the synthesis of submicron calcium carbonate using a microfluidic chip with a T-shaped oil supply for droplet-based synthesis to facilitate control over the formation of submicron calcium carbonate particles.

Microfluidic Vaterite Synthesis: Approaching the Nanoscale Particles.

The challenge of continuous CaCO particle synthesis is addressed using microfluidic technology. A custom microfluidic chip was used to synthesize CaCO nanoparticles in vaterite form. Our focus revolved around exploring one-phase and two-phase synthesis methods tailored for the crystallization of these nanoparticles.

Properties of Degradable Polyhydroxyalkanoates Synthesized from New Waste Fish Oils (WFOs).

The synthesis of PHA was first investigated using WFOs obtained from smoked-sprat heads, substandard fresh sprats, and fresh mackerel heads and backbones. All the WFOs ensured the growth of the wild-type strain B-10646 and the synthesis of PHA, regardless of the degree of lipid saturation (from 0.52 to 0.

Mitigation of Physical Aging of Polymeric Membrane Materials for Gas Separation: A Review.

The first commercial hollow fiber and flat sheet gas separation membranes were produced in the late 1970s from the glassy polymers polysulfone and poly(vinyltrimethyl silane), respectively, and the first industrial application was hydrogen recovery from ammonia purge gas in the ammonia synthesis loop. Membranes based on glassy polymers (polysulfone, cellulose acetate, polyimides, substituted polycarbonate, and poly(phenylene oxide)) are currently used in various industrial processes, such as hydrogen purification, nitrogen production, and natural gas treatment. However, the glassy polymers are in a non-equilibrium state; therefore, these polymers undergo a process of physical aging, which is accompanied by the spontaneous reduction of free volume and gas permeability over time.

Quantitative Raman microscopy to describe structural organisation in hollow microcrystals built from silicon catecholate and amines.

Macroscopic scale hollow microcrystals are a promising group of materials for gas and liquid uptake as well as sensing. In this contribution we describe the structure of hollow hexagonal cross-section crystals formulated as salts of a silicon catecholate anion and a tetramethylenediamine (TEMED) cation. Using a combination of X-ray single crystal diffraction, Raman spectroscopy and quantum chemistry we explore the structural properties of the hollow microcrystals.

Temperature Dependence of Light Hydrocarbons Sorption and Transport in Dense Membranes Based on Tetradecyl Substituted Silicone Rubber.

Solubility-selective polymer membranes are promising materials for C hydrocarbons removal from methane and other permanent gas streams. To this end, a dense solubility-selective membrane based on crosslinked poly(tetradecyl methyl siloxane) was synthesized. Sorption of methane, ethane, and -butane in the polymer was measured in the temperature range of 5-35 °C.

Raman microscopy tracks maturity of melanin intermediates in , a plant pathogen.

We use Raman microscopy to describe the structure and chemical composition of both conidiophore and hyphae of , a common plant pathogen. To interpret experimental data, we use density functional theory (DFT) to compute Raman tensors specific to an important fungal glycopeptide, a segment of α-chitin, and several naphthalene-based precursors of increasing complexity, which we propose play a role in the melanin synthesis pathway. Using spectral interpretations based on quantum chemical validation, we review microscopy images reconstructed for specific Raman activities and describe differences in distributions of structural components, photo-protective secondary naphthalene-based pigments, and proteins in both spores and hyphal filaments.

Diazines on graphene: adsorption, structural variances and electronic states.

We conduct quantum studies of adsorption of diazine heterocycles on graphene to discuss experimental thermodynamics of gas-phase adsorption of pyridazine, pyrimidine and pyrazine on graphitized thermal carbon black, as reported previously. Using Born-Oppenheimer molecular dynamics and density functional studies, we characterize structural and electronic tendencies of the heterocycles on graphene. The theoretical studies predict the adsorption of pyridazine, pyrazine and pyrimidine to cause electronic perturbations of dipole, quadrupole and mixed spatial characters, respectively, resulting in a red shift of the electronic components of the heterocycles to modulate graphene electronics upon admixing of diazine orbital components with the π states of the substrate.

Selective Destruction of Soluble Polyurethaneimide as Novel Approach for Fabrication of Insoluble Polyimide Films.

Polymeric coatings and membranes with extended stability toward a wide range of organic solvents are practical for application in harsh environments; on the other hand, such stability makes their processing quite difficult. In this work, we propose a novel method for the fabrication of films based on non-soluble polymers. The film is made from the solution of block copolymer containing both soluble and insoluble blocks followed by selective decomposition of soluble blocks.

Cu(Proline) Complex: A Model of Bio-Copper Structural Ambivalence.

Complexes of Cu(d) with proline may be considered a simple model to address the structural flexibility and electronic properties of copper metalloproteins. To discuss optical electronic spectra and infrared spectral responses, we use quantum chemistry applied to model systems prepared under different geometries and degree of hydration. A comparison of experimental data with calculations indicates that first explicit neighbor water clustering next to the Cu(d) complex is critical for a correct description of the electronic properties of this system.

Polymeric Membranes for Oil-Water Separation: A Review.

This review is devoted to the application of bulk synthetic polymers such as polysulfone (PSf), polyethersulfone (PES), polyacrylonitrile (PAN), and polyvinylidene fluoride (PVDF) for the separation of oil-water emulsions. Due to the high hydrophobicity of the presented polymers and their tendency to be contaminated with water-oil emulsions, methods for the hydrophilization of membranes based on them were analyzed: the mixing of polymers, the introduction of inorganic additives, and surface modification. In addition, membranes based on natural hydrophilic materials (cellulose and its derivatives) are given as a comparison.

Mapping blood biochemistry by Raman spectroscopy at the cellular level.

We report how Raman difference imaging provides insight on cellular biochemistry as a function of sub-cellular dimensions and the cellular environment. We show that this approach offers a sensitive diagnostic to address blood biochemistry at the cellular level. We examine Raman microscopic images of the distribution of the different hemoglobins in both healthy (discocyte) and unhealthy (echinocyte) blood cells and interpret these images using pre-calculated, accurate pre-resonant Raman tensors for scattering intensities specific to hemoglobins.

Determination of the Degree of Crystallinity of Poly(2-methyl-2-oxazoline).

A new method for purification of 2-methyl-2-oxazoline using citric acid was developed and living cationic ring-opening polymerization of 2-methyl-2-oxazoline was carried out. Polymerization was conducted in acetonitrile using benzyl chloride-boron trifluoride etherate initiating system. According to DSC data, the temperature range of melting of the crystalline phase of the resulting polymer was 95-180 °C.

Mixed-Gas Selectivity Based on Pure Gas Permeation Measurements: An Approximate Model.

An approximate model based on friction-coefficient formalism is developed to predict the mixed-gas permeability and selectivity of polymeric membranes. More specifically, the model is a modification of Kedem's approach to flux coupling. The crucial assumption of the developed model is the division of the inverse local permeability of the mixture component into two terms: the inverse local permeability of the corresponding pure gas and the term proportional to the friction between penetrants.

Anchoring of a hydrophobic heptapeptide (AFILPTG) on silica facilitates peptide unfolding at the abiotic-biotic interface.

A hydrophobic heptapeptide, with sequence AFILPTG, as part of a phage capsid protein binds effectively to silica particles carrying negative charge. Here, we explore the silica binding activity of the sequence as a short polypeptide with polar N and C terminals. To describe the structural changes that occur on binding, we fit experimental infrared, Raman and circular dichroism data for a number of structures simulated in the full configuration space of the hepta-peptide using replica exchange molecular dynamics.

Wide-Ranging Multitool Study of Structure and Porosity of PLGA Scaffolds for Tissue Engineering.

In this study, the nanoscale transformation of the polylactic-co-glycolic acid (PLGA) internal structure, before and after its supercritical carbon dioxide (sc-CO) swelling and plasticization, followed by foaming after a CO pressure drop, was studied by small-angle X-ray scattering (SAXS) for the first time. A comparative analysis of the internal structure data and porosity measurements for PLGA scaffolds, produced by sc-CO processing, on a scale ranging from 0.02 to 1000 μm, was performed by SAXS, helium pycnometry (HP), mercury intrusion porosimetry (MIP) and both "lab-source" and synchrotron X-ray microtomography (micro-CT).

The protealysin operon encodes emfourin, a prototype of a novel family of protein metalloprotease inhibitors.

Protealysin is a Serratia proteamaculans metalloproteinase of the M4 peptidase family and the prototype of a large group of protealysin-like proteases (PLPs). PLPs are likely involved in bacterial interaction with plants and animals as well as in bacterial pathogenesis. We demonstrated that the PLP genes in bacteria colocalize with the genes of putative conserved proteins.

The comparative analysis of the properties and structures of purine nucleoside phosphorylases from thermophilic bacterium HB27.

Two recombinant purine nucleoside phosphorylases from thermophilic bacterium HB27 encoded by genes TT_C1070 (PNPI) and TT_C0194 (PNPII) were purified and characterized. The comparative analysis of their sequences, molecular weight, enzymes specificity and kinetics of the catalyzed reaction were realized. As a result, it was determined that the PNPI is specific to guanosine while the PNPII to adenosine.

Polariton condensation and surface enhanced Raman in spherical ZnO microcrystals.

Preparation and characterization of polariton Bose-Einstein condensates in micro-cavities of high quality are at the frontier of contemporary solid state physics. Here, we report on three-dimensional polariton condensation and confinement in pseudo-spherical ZnO microcrystals. The boundary of micro-spherical ZnO resembles a stable cavity that enables sufficient coupling of radiation with material response.

Search for Electron Antineutrino Appearance in a Long-Baseline Muon Antineutrino Beam.

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events.

[New morphometric criteria in the study of pathogenesis of normal-tension glaucoma].

Introduction: Studying the factors that contribute to the disturbance of transmembrane pressure gradient is a topical task in the research of pathogenesis of normal-tension glaucoma (NTG).

Purpose: To measure and compare the thickness and depth of lamina cribrosa (LCT and LCD), as well as optic nerve subarachnoid space width (ONSASW) in patients with NTG and healthy individuals.

Material And Methods: The first group included 12 patients (23 eyes) aged from 58 to 74 years (average age 66.

Towards a solution of the inverse X-ray diffraction tomography challenge: theory and iterative algorithm for recovering the 3D displacement field function of Coulomb-type point defects in a crystal.

The theoretical framework and a joint quasi-Newton-Levenberg-Marquardt-simulated annealing (qNLMSA) algorithm are established to treat an inverse X-ray diffraction tomography (XRDT) problem for recovering the 3D displacement field function f(r - r) = h · u(r - r) due to a Coulomb-type point defect (Ctpd) located at a point r within a crystal [h is the diffraction vector and u(r - r) is the displacement vector]. The joint qNLMSA algorithm operates in a special sequence to optimize the XRDT target function {\cal F}\{ {\cal P} \} in a χ sense in order to recover the function f(r - r) [{\cal P} is the parameter vector that characterizes the 3D function f(r - r) in the algorithm search]. A theoretical framework based on the analytical solution of the Takagi-Taupin equations in the semi-kinematical approach is elaborated.

Digging deeper: structural background of PEGylated fibrin gels in cell migration and lumenogenesis.

Fibrin is a well-known tool in tissue engineering, but the structure of its modifications created to improve its properties remains undiscussed despite its importance, in designing biomaterials that ensure cell migration and lumenogenesis. We sought to uncover the structural aspects of PEGylated fibrin hydrogels shown to contribute to angiogenesis. The analysis of the small-angle X-ray scattering (SAXS) data and modeling revealed that the PEGylation of fibrinogen led to the formation of oligomeric species, which are larger at a higher PEG : fibrinogen molar ratio.