Ray Analysis Research Articles

A label free nanosensing platform for the detection of cervical cancer through analysis of ultratrace DNA hybridization

BackgroundCervical cancer is a major health problem caused by human papillomavirus (HPV) infection which affects more than 500,000 women every year worldwide. Majority of the cases occur in less developed countries since there are lack of availability of effective screening methods for diagnosis. Therefore, a fast, accurate and early detection platform is developed for HPV detection. The current study describes a sensitive, specific, easy and a cost-effective label free DNA based electrochemical biosensor for HPV-16 detection. MethodologyDetection of HPV-16 is performed by an electrochemical platform coated with chitosan capped gold nanoparticles (ccAuNPs). These nanoparticles were characterized using Ultraviolet–visible (UV–vis) analysis, Fourier Transfer Infrared Ray analysis (FT-IR) and Transmission Electron Microscope (TEM). The probe DNA (PDNA) was then immobilized onto the nanoparticle modified electrode and hybridized with target DNA (TDNA). The electrochemical analysis was done at each step of modification using cyclic voltammetry (CV) and square wave voltammetry (SWV). ResultsThe biosensor responds to TDNA concentration range from 1 pM to 1 μM and the limit of detection is 1 pM with the sensitivity of 0.39 mA pM−1. This proposed biosensor achieved good performance of the PDNA/ccAuNPs modified ITO electrode. ConclusionsThe results illustrate that the developed nanotechnology-based electrochemical DNA biosensor provides very low detection limit in picomolar level. It also exhibited excellent selectivity and stability, which is important for potential applications in the onsite analysis of HPV-16 and in medical diagnosis.

Comparative study of zirconomer versus equia fil on surface microhardness and remineralization (An in vitro study).

Aim: This research was designed to evaluate the effect of different types of glass ionomer restorations(GIC) on Surface microhardness and Remineralization of dentin. Materials and methods: Three of (GIC) (medifil, equia fil and zirconomer) were used.A total number of 32 human premolar teeth were used in this study. Standardized two class V cavities, one on the buccal and other on lingual surface of each tooth were prepared.The teeth were sectioned mesio-distally to get (64) then divided into three equal main groups (n=21) according to the restorative materials, group (M): medifil group (E): equia fil group and (Z): zirconomer group. Each group was further subdivided into three equal divisions (n=7) according to the storage times; one day (S1), one month (S2) and three months (S3). The specimens were sectioned longitudinally along to produce two blocks. One part was mounted in epoxy resin for microhardness testing, and the other for energy dispersive x -ray analysis(EDX).Specimens were stored in artificial saliva for one day, one month and three months .A microhardness tester was used to measure the Vickers hardness number (VHN).Results:It was found that the highest mean value of surface micro hardness and remineralization was recorded for medi fil group, while the lowest mean value was recorded for equia fil group. Pair-wise there is no-significant between one month and three month storage. Conclusion: all (GIC) restorations show remineralization to tooth structures also zirconomer over powered by conventional (GIC) because its high fluoride release finally equia fil show increase remineralization with time.

Trajectory Analysis of Galactic Cosmic Rays Invading into the Heliosphere

Abstract The trajectories of galactic cosmic-ray protons invading the heliosphere are investigated by using numerical simulations. A time stationary global heliosphere is first reproduced by using a high-resolution MHD simulation. Then, motions of a number of test particles (protons) distributed in the virtual heliosphere are numerically solved. When the initial particle Lorentz factor is 10 (∼10 GeV), the motions of particles are strongly affected by small-scale heliospheric structures reflecting the small gyroradii of the particles. Particles can enter the heliosphere from many parts (nose, flank, and tail) of the heliopause. Once they have entered, they expand in the region where the magnetic field is locally weak, such as the heliopause and the heliospheric current sheet. On the other hand, particles have difficulty invading upstream of the termination shock. We found a variety of invading particle trajectory patterns such as current sheet drift, polar drift, spiral motion, shock drift, and Fermi-like acceleration. In the latter two, particles are accelerated. When the initial particle Lorentz factor is 1000 (∼1 TeV), the particles are insensitive to the small-scale structures of the heliosphere due to their large gyroradii. Some particles show eccentric motions due to resonant interaction with the large-scale eddy in the heliotail. Some other particles passing by the heliosphere are mirror reflected due to the bottleneck structure of interstellar magnetic field surrounding the heliosphere and return back to enter the heliosphere.

Fatty acids and elemental composition changes in honey bee workers (Apis mellifera) irradiated with gamma radiation

The effect of gamma radiation on the whole body contents of fatty acids and elemental composition were investigated for honey bee workers Apis mellifera. The data indicated that the quantities of fatty acids and elemental composition within the whole body of the workers of A. mellifera were affected significantly especially at the dose of 20 rad. Data obtained indicated that the palmitic (C16:0), oleic (C18:1) and linolic (C18:2) acids increased when workers irradiated with 20 rad. Analysis of the 7 elements; Mg, P, K, Ca, Fe, Cu and Zn were detected by energy dispersive X- ray analyzer by using (EDX). The most dominant elements in control workers were K followed by P; the Fe occupied the last order. In irradiated adult workers with 20 rad, K recorded a higher percentage than its control. In the same dose (20 rad), the total heavy metals Copper + Zink (Cu + Zn) decreased from 19.81% to 14.8%.

Experimental signatures of a new dark matter WIMP

The WIMP proposed here yields the observed abundance of dark matter, and is consistent with the current limits from direct detection, indirect detection, and collider experiments, if its mass is GeV/c 2. It is also consistent with analyses of the gamma rays observed by Fermi-LAT from the Galactic center (and other sources), and of the antiprotons observed by AMS-02, in which the excesses are attributed to dark matter annihilation. These successes are shared by the inert doublet model (IDM), but the phenomenology is very different: the dark matter candidate of the IDM has first-order gauge couplings to other new particles, whereas the present candidate does not. In addition to indirect detection through annihilation products, it appears that the present particle can be observed in the most sensitive direct-detection and collider experiments currently being planned.

Novel Products of Nitrosation of a Series of Trihydroxybenzene Derivatives and Their Complexation with Cu(II), Cd(II) and Fe(III): Synthesis, Characterization, and Theoretical Modeling

AbstractThree novel bis‐ and trinitroso compounds derived from 1,3,5‐trihydrohybenzene (phloroglucinol), 2,4,6–trihydroxy benzoic acid, and 2,4,6‐trihydroxyacetophenone were isolated, their spectral characteristics, ionization constants and thermodynamic parameters of dissociation process were calculated. The comparison of the stability of nitroso and hydroxylimino tautomeric forms was performed by DFT calculations. Nine complexes of the ligands with Cu(II), Cd(II), and Fe(III), were isolated and studied by elemental analyses, X Ray analysis and spectroscopic methods. According to the crystal structure determination, the Cd complex with the phloroglucinol based ligand exists in the form of a binuclear compound. The QTAIM Bader topological analysis indicated that the binuclearity of the Cd complex is due to strong interatomic interactions between Cd atoms with bifurcate carbonyl groups of the ligands and strong H‐interactions involving coordinated and lattice water molecules. The equilibria of reactions of complex formation of the organic species with Cu2+, Cd2+, and Fe3+ was studied by spectrophotometric titration, and the composition of the complexes in solutions and their stability constants were calculated. The ability of the isolated organics to remove metal cations from the aqueous solutions was studied in the pH interval 3–6 and the rate of Cu2+ removal from aqueous solutions was found close to 100 %.

Inhibitive Efficiency of Zinc Organo Amino Phosphate for The Corrosion of α-Brass in 0.5 M Sulphuric Acid Solution.(Dept.M)

A study has been made to investigate the mechanism of dezincification and elelctrochemical behaviour 70/30 brass in sulphuric acid in absence and presence of Zinc Organa Amino Phosphate (ZOAP) inhibitor using the weight loss method, solution analysis and electrochemical technique. Attacked surfaces were analyzed by optical metallography and X -ray analysis. Results showed that 20 AP inhibitor is able to minimize the rate of dezincification due to the formation of a C4H6 (NH2)4 Zn3 (P3 O10)2. 9H2O complex compound on the metal surface.

Superposed Epoch Analysis of Galactic Cosmic Rays and Solar Wind based on ACE Observations During Two Recent Solar Minima

Abstract Based on galactic cosmic ray (GCR) and plasma observations from the ACE spacecraft, in this work, we analyze the relation between the GCR counts and the solar wind parameters during two recent two solar minima (for the years 2007.0–2009.0, and 2016.5–2018.5) by means of the superposed epoch analysis (SEA) method. The results indicate that GCRs are strongly modulated by the co-rotating interaction regions (CIRs) in the solar wind, and that the occurrences of stream interfaces (SIs) between fast and slow solar wind are correlated with a depression in GCR counts. The so-called “snow plow” effect of GCR variation prior to SI crossing appears during the first solar minimum, and the GCR counts decrease after the crossing, corresponding to a sudden drop in the diffusion coefficient at the SIs. The gradient of GCR counts shows that the transport efficiency of GCRs is low (high), relative to slow (fast) solar wind. However, during the second solar minimum, we see a completely opposite scenario; the “snow plow” effect is not observed, and GCR transport becomes faster in slow solar wind, and slower in fast solar wind. In addition, heliospheric current-sheet crossings also correlate with GCR counts. Particles drift along the current sheet, then accumulate in a pileup structure, where diffusion and drift effects may be balanced. It is found that the drift effect rivals the diffusion and convection on the GCR transport at 1 au during the two solar minima.

Measurement of γ rays from 6LiF tile as an inner wall of a neutron-decay detector

A neutron lifetime measurement conducted at the Japan Proton Accelerator Research Complex (J-PARC) is counting the number of electrons from neutron decays with a time projection chamber (TPC). The γ rays produced in the TPC cause irreducible background events. To achieve the precise measurement, the inner walls of the TPC consist of 6Li-enriched lithium-fluoride (6LiF) tiles to suppress the amount of γ rays. In order to estimate the amount of γ rays from the 6LiF tile, prompt gamma ray analysis (PGA) measurements were performed using germanium detectors. We reconstructed the measured γ-ray energy spectrum using a Monte Carlo simulation with the stripping method. Comparing the measured spectrum with a simulated one, the number of γ rays emitted from the6LiF tile was (2.3+0.7−0.3) × 10−4 per incident neutron. This is 1.4+0.5−0.2 times the value assumed for a mole fraction of the 6LiF tile. We concluded that the amount of γ rays produced from the 6LiF tile is not more twice the originally assumed value.

Catalytic Cracking of Furfural Extract-40 over Ni/HY-Zeolite Catalyst

Modifying of HY/Zeolite is by loading nickel for applying catalyst in thermal catalytic cracking of furfural extract-40 from the lubricating base oil unit. The study involved the characterizing of HY-zeolite and promoted catalyst with nickel by X-ray diffraction analysis, Scanning electron microscopy (SEM), BET (Brunauer, Emmett, and Teller), and infrared ray analyses FTIR. The catalytic thermal cracking tubular reactor with a fixed bed with two type catalysts; HY/zeolite and Ni HY/zeolite, individually at a temperature of 580oC with LHSV 5h-1 was investigated. The results indicated that increase the conversion of catalytic cracking of furfural extract-40 also increases the yield of useful petroleum products and decreases the coke depsite on the Ni HY-Zeolite catalyst.

Catalytic Cracking of Furfural Extract-40 over Ni/HY-Zeolite Catalyst

Modifying of HY/Zeolite is by loading nickel for applying catalyst in thermal catalytic cracking of furfural extract-40 from the lubricating base oil unit. The study involved the characterizing of HY-zeolite and promoted catalyst with nickel by X-ray diffraction analysis, Scanning electron microscopy (SEM), BET (Brunauer, Emmett, and Teller), and infrared ray analyses FTIR. The catalytic thermal cracking tubular reactor with a fixed bed with two type catalysts; HY/zeolite and Ni HY/zeolite, individually at a temperature of 580oC with LHSV 5h-1 was investigated. The results indicated that increase the conversion of catalytic cracking of furfural extract-40 also increases the yield of useful petroleum products and decreases the coke depsite on the Ni HY-Zeolite catalyst.

New Schiff Base as Selective and Sensitive Detection of Copper Ions in Aqueous Solvent

AbstractDetection of metals in aqueous solution is advantageous in the field of food, nutrition and drug chemistry. Hence, a new sensor was designed for the selective and sensitive detection of Cu2+ ions in the aqueous media. Herein, Schiff base L=(E)‐N′‐((1H‐indol‐2‐yl)methylene)isonicotinohydrazide acts as a sensor which consist of isaniazid and indole moiety connected with azomethine linkage. Single crystal X ray analysis along with other spectroscopic methods was used to confirm the structure of the synthesized ligand. Theoretical calculations were performed which gave satisfactory correlation with experimental results. A naked eye color change from colorless to yellow was observed upon addition of Cu(II) ions in synthesized Schiff base sensor. UV‐Visible absorption spectroscopy was used for the further sensing experiments and a red shift of 63 nm was observed only in the case of Copper ions in a pH range of 6–8, this confirms the selective nature of Schiff base sensor towards the Cu2+ ions. Negligible interference of other metal ions in the sensing of copper ions was confirmed by interference study.Calculated limit of detection for copper detection in aqueous media was 0.05 μM. To check the practical applications of the studied Schiff base as a chemosensor, test strips test was also performed.

Design of a resonant Luneburg lens for surface acoustic waves

In this work we employ additive manufacturing to print a circular array of micropillars on an aluminium slab turning its top surface into a graded index metasurface for surface acoustic waves (SAW). The graded metasurface reproduces a Luneburg lens capable of focusing plane SAWs to a point. The graded index profile is obtained by exploiting the dispersion properties of the metasurface arising from the well-known resonant coupling between the micropillars (0.5 mm diameter and variable length ∼3 mm) and the surface waves propagating in the substrate. From the analytical formulation of the metasurface’s dispersion curves, a slow phase velocity mode is shown to arise from the hybridisation of the surface wave with the pillar resonance. This is used to compute the radial height profile corresponding to the refractive index given by Luneburg’s equation. An initial validation of the lens design, achieved through ray theory, shows that ray trajectories have a strong frequency dependence, meaning that the lens will only work on a narrow band. An ultrasonic experiment at 500 kHz where plane SAWs are generated with a piezoelectric transducer and a laser scanner measures the out of plane displacement on the metasurface, validates the actual lens performance and the manufacturing technique. Finally, comparison between the ray analysis and experimental results offers insight into the behaviour of this type of metasurface especially in the proximity of the acoustic bandgaps and highlights the possibility for acoustic shielding.

Qualitative and quantitative assessment of the potential effect of cigarette smoking on enamel of human smokers’ teeth

ObjectiveThis study aimed to examine the potential changes in enamel surface of human smokers’ teeth. Materials and methodsForty extracted permanent, human, noncarious anterior teeth were used in this study. Half of these teeth were obtained from heavy smokers, while the other half of teeth were collected from nonsmokers (control teeth). The teeth were then subjected for scanning electron microscopic examination together with energy dispersive X ray and micro-hardness analysis to evaluate the qualitative and quantitative effect of smoking respectively. ResultsSEM of smokers’ teeth showed variable degrees of destruction from small areas of demineralization as holes and pits to destruction and deterioration of the organizational pattern of the rod substance. Moreover, areas of defective remineralization were detected. The microhardness, calcium and phosphorus weight % significantly decreased whereas the Ca/P ratio was significantly increased. ConclusionCigarette smoking adversely affected the ultrastructure and mechanical properties of enamel and even hindered the normal remineralization process thus cigarette smoking cessation should be promoted in the dental office daily practices.

Evaluation of Nickel Catalysts Supported in Dry Methane Reform Aiming at Hydrogen Production/Case of Supports: SiO2, La2O3 MCM-41, and Al2O3

The importance of biogas was evidenced by the dry reforming reaction using a nickel catalyst supported: Al 2 O 3 , SiO 2 , MCM 41 and La 2 O 3 . The catalysts were characterized using electron scanning microscopy, Chemisorption, BET, X- Ray analysis. The reaction was conducted in a quartz reactor, atmospheric pressure and at temperatures of 500, 600 and 700 o C. The catalysts showed different conversions in syngas with the change of temperature, and H 2 /CO ratio variable. The nickel catalyst supported on alumina showed the most activity in the three reaction temperatures. The conversion of supported nickel catalysts, in the examined temperatures, decreased in the following order: Ni/Al 2 O 3 ˃ Ni/La 2 O 3 ˃ NiSi/O 2 ˃ Ni/MCM41. The Ni/Al 2 O 3 and Ni/MCM-41 catalysts showed H 2 /CO greater than one at all temperatures. DOI: http://dx.doi.org/10.17807/orbital.v12i3.1495

Up‐and‐down journeys: The making ofLatinAmerica's uniqueness for the study of cosmic rays

In 1942, American Nobel Prize-winning physicist Arthur Compton pointed out that, “Because in this field of cosmic ray studies certain unique advantages are given by their geographical position, this field of physics has been especially emphasized in South America.” This paper seeks to interrogate the making of Latin America's uniqueness with respect to cosmic-ray research through an analysis that considers Compton's geographical argument, but also goes beyond it, referring to the interactions of nature, knowledge, practices, scientific communities, and diplomacy. To begin with, it highlights the place-based strategies and practices associated with cosmic-ray research. Once research in the field at different altitudes demonstrated that cosmic rays traveled from outer space to the Earth surface, their nature was scrutinized by expeditions that covered broad vertical and horizontal expanses. The study of cosmic rays in Latin America displayed the mobilization of that strategy, which reinforced the reliability of certain sites located at high altitudes and close to the geomagnetic equator in projected investigations. Moreover, such analysis of cosmic rays involved research practices in the field, the emergence of (local, regional, or international) research traditions, and the creation of spaces of knowledge at different scales. By centering on the interaction of knowledge and place, this paper shows that an exploration of the “up-and-down journeys” of cosmic-ray research in Latin America expands our understanding of the geographies and practices of 20th-century physics.

Method for Estimating Optimal Position of S-Band Relay Station through Path Loss Analysis in an Outdoor Environment

This article investigates a novel estimation method to optimize the position of a relay station of the S-band telemetry system in outdoor environments. To determine an optimal relay station position, complex terrain surface and buildings near the Naro Space Center are included in the EM (Electromagnetic) simulation. The optimal relay station position is then determined using the estimation method by comparing the path losses from the rocket to the main station and some candidate positions of the relay station. To better understand the path loss, the ray analysis is also conducted, and the result demonstrates that once the rocket altitude to be covered by the relay station is determined, it is possible to find the optimum position of the relay station.

Analysis of Scattering Rays and Shielding Efficiency through Lead Shielding for 0.511 MeV Gamma Rays Based on Skin Dose

Analysis of Scattering Rays and Shielding Efficiency through Lead Shielding for 0.511 MeV Gamma Rays Based on Skin Dose

Metallurgical and mechanical properties of SiC/ B4C reinforced with aluminum composites synthesized by mechanical alloying

In advanced engineering dynamic environment applications demands in high performance and new composite materials. The hybrid composite materials are satisfying the recent engineering application demands and also improve the particular unique properties of composite materials. In present work, investigate the mechanical and metallurgical characterizations of composite materials fabricated by powder metallurgy pressure die casting process for various weight percentage of Silicon carbide (SiC), Boron carbide (B4C) reinforced with aluminum. The main objective of the paper is to improve the metallurgical and hardness properties of aluminum matrix composite materials. The Scanning Electron Microscopy (SEM) and Energy Dispersive X- RAY (EDX) analysis used to identify the humongous dispersion of hybrid composite. The hardness test was performed and it was found that the hybrid composite materials had produced the superior than base aluminum

A complex interdependence of thermal conductivity and lubricity of two solid lubricants to control the tribo-performance of PAEK based composites

In this work, a series of four composites was developed by incorporation of two solid lubricants (SLs) (total amount 20 wt % and added in a complementary manner) viz. graphite (well known for thermal conductivity as well as good lubricity) and PTFE (Poly tetra fluoroethylene) (well known for excellent lubricity, but poor thermal conductivity) into PAEK (Poly aryl ether ketone) reinforced with short glass fibres. It was of interest to investigate how these two SLs work together, especially when with increasing contents of PTFE, thermal conductivity (TC) of the composites would decrease and lubricity should increase. The composites were characterized for density, TC and mechanical properties. Tribo-testing was done by varying load, velocity and against mild steel counterface. The composites showed very low wear rates (K0 ≈ 10−16 m3/Nm) and ultra-low coefficient of friction (μ ≈ 0.03). With increase in PTFE contents, wear resistance and also TC decreased indicating TC was a dominating parameter to control the wear of composites. Worn surfaces were studied with scanning electron microscopy (SEM), energy dispersive X ray analysis (EDAX), Raman spectroscopy, XPS (X-ray photoelectron spectroscopy) and wettability analysis to understand the wear mechanisms.