Synthesis and characterization of novel polymeric organic–inorganic complex framework based on sodium 2,4-dioxo-6-aryl-3-oxa-bicyclo[3.1.0]hexane-1,5-dicarboxylate (SDAOBDC) with three-dimensional hybrid networks

Synthesis and characterization of novel polymeric organic–inorganic complex based on sodium 2,4-dioxo-6-aryl-3-oxa-bicyclo[3,1,0]hexane-1,5-dicarboxylate with three-dimensional hybrid networks were reported. The polymeric complex was crystallizing in the triclinic, space group P1. As determined by X-ray single-crystal analysis, in this compound each Na ion is coordinated by six O atoms: two from different carbonyl oxygen atom of carboxylic acid groups, two from bridged carbonyl oxygen atom of carboxylic acid groups, one from the carbonyl oxygen atom of cyclic anhydride and one from water molecule. The structure characterization was done by means of IR, ¹H, ¹³C NMR, UV–Vis spectroscopies, Tg, flame photometry and X-ray crystallographic analysis.     

Evaluation of the antioxidant and antibacterial properties of ethanol extracts from berries,leaves and stems of Hedera pastuchovii Woron. ex Grossh

This study was designed to examine the total phenolic and flavonoid contents, radical scavenging and antibacterial activity of the ethanolic extracts from leaves, berries and stems of Hedera pastuchovii Woron. ex Grossh. The berry extract, which contained the highest phenolic and flavonoid compounds, showed an appreciable DPPH^√ scavenging ability in comparison with leaf and stem extracts. The various extracts exhibited moderate to good activity against both Gram-negative and Gram-positive bacteria, and the effectiveness of leaf extract was higher for all tested bacteria.     

The effect of the low Reynolds number k-e turbulence models on simulation of the enhanced and deteriorated convective heat transfer to the supercritical fluid flows

One of the most important challenges in mathematical modeling of convective heat transfer to the turbulent flow of a supercritical fluid is the turbulence modeling. The turbulence modeling, like other aspects of the supercritical fluid flows, seems to be high affected by the large variations of the fluid properties which needs to be further investigated. A two dimensional CFD code has been developed and used in this study to examine a number of the low Reynolds number k-e turbulence models. Both flow conditions corresponding to the heat transfer enhancement and deterioration have been studied. The results appear to be quite sensitive to the choice of the turbulence model, especially in the deteriorated regime of heat transfer. The turbulence model assisting the two-dimensional numerical model of the present study to best fit the experiments has been determined for both cases of the enhanced and deteriorated heat transfer. That is while the jump in the wall temperature occurring in the deteriorated regime of heat transfer is over- predicted by the present numerical code regardless of the turbulence model used.     

Lensless imaging for simultaneous microfluidic sperm monitoring and sorting

5.3 million American couples of reproductive age (9%) are affected by infertility, among which male factors account for up to 50% of cases, which necessitates the identification of parameters defining sperm quality, including sperm count and motility. In vitro fertilization (IVF) with or without intra cytoplasmic sperm injection (ICSI) has become the most widely used assisted reproductive technology (ART) in modern clinical practice to overcome male infertility challenges. One of the obstacles of IVF and ICSI lies in identifying and isolating the most motile and presumably healthiest sperm from semen samples that have low sperm counts (oligozoospermia) and/or low sperm motility (oligospermaesthenia). Microfluidic systems have shown potential to sort sperm with flow systems. However, the small field of view (FOV) of conventional microscopes commonly used to image sperm motion presents challenges in tracking a large number of sperm cells simultaneously. To address this challenge, we have integrated a lensless charge-coupled device (CCD) with a microfluidic chip to enable wide FOV and automatic recording as the sperm move inside a microfluidic channel. The integrated system enables the sorting and tracking of a population of sperm that have been placed in a microfluidic channel. This channel can be monitored in both horizontal and vertical configuration similar to a swim-up column method used clinically. Sperm motilities can be quantified by tracing the shadow paths for individual sperm. Moreover, as the sperm are sorted by swimming from the inlet towards the outlet of a microfluidic channel, motile sperm that reach the outlet can be extracted from the channel at the end of the process. This technology can lead to methods to evaluate each sperm individually in terms of motility response in a wide field of view, which could prove especially useful, when working with oligozoospermic or oligospermaesthenic samples, in which the most motile sperm need to be isolated from a pool of small number of sperm.     

Influence of flow on longevity of superhydrophobic coatings

Previous studies have demonstrated the capability of superhydrophobic surfaces to produce slip flow and drag reduction, which properties hold considerable promise for a broad range of applications. However, in order to implement such surfaces for practical utilizations, environmental factors such as water movement over the surface must be observed and understood. In this work, experiments were carried out to present a proof-of-concept study on the impact of flow on longevity of polystyrene fibrous coatings. The time-dependent hydrophobicity of a submerged coating in a pressure vessel was determined while exposing the coating to a rudimentary wall-jet flow. Rheological studies were also performed to determine the effect of the flow on drag reduction. The results show that the longevity of the surface deteriorates by increasing the flow rate. The flow appears to enhance the dissolution of air into water, which leads to a loss of drag reduction.     

B-decay signatures of warped top-condensation

We point out that the light radion ?   in a recently proposed Warped Top-Condensation Model (WTCM), can provide distinct signatures in b→s?$b\to s?$, where the on-shell ? can decay with displaced vertices. We find that some of the parameter space of these models is constrained by B-meson and astrophysical data. Future B-decay measurements can lead to the discovery of the WTCM.     

Spinning particles in Schwarzschild–de Sitter space–time

After considering the reference case of the motion of spinning test bodies in the equatorial plane of the Schwarzschild space–time, we generalize the results to the case of the motion of a spinning particle in the equatorial plane of the Schwarzschild–de Sitter space–time. Specifically, we obtain the loci of turning points of the particle in this plane. We show that the cosmological constant affect the particle motion when the particle distance from the black hole is of the order of the inverse square root of the cosmological constant.     

Unified origin for baryonic visible matter and antibaryonic dark matter

We present a novel mechanism for generating both the baryon and dark matter densities of the Universe. A new Dirac fermion X carrying a conserved baryon number charge couples to the standard model quarks as well as a GeV-scale hidden sector. CP-violating decays of X, produced nonthermally in low-temperature reheating, sequester antibaryon number in the hidden sector, thereby leaving a baryon excess in the visible sector. The antibaryonic hidden states are stable dark matter. A spectacular signature of this mechanism is the baryon-destroying inelastic scattering of dark matter that can annihilate baryons at appreciable rates relevant for nucleon decay searches.     

Synthesis,Characterization, and Evaluation of Antibacterial and Antioxidant Activities of Novel Benzoxazinones and Benzoxathiinones

In this work, the new benzoxazinones and benzoxathiinones were synthesized from reaction of alkyl X‐phenylpropiolates and aminophenol (or 2‐mercaptophenol) in the presence of triphenylphosphine. Their antibacterial activities were studied against Gram‐positive bacteria and Gram‐negative bacteria using the disc diffusion method. The obtained results showed that these compounds are more effective against Gram‐positive bacteria than against Gram‐negative bacteria. Also, evaluation of antioxidant activity of the obtained products showed that they have high to excellent antioxidant activity (79.2–93.6%).