FRBs Lensed by Point Masses. II. The Multipeaked FRBs from the Point View of Microlensing

The microlensing effect has developed into a powerful technique for a diverse range of applications including exoplanet discoveries, structure of the Milky Way, constraints on MAssive Compact Halo Objects, and measurements of the size and profile of quasar accretion disks. In this paper, we consider a special type of microlensing events where the sources are fast radio bursts (FRBs) with ∼milliseconds (ms) durations for which the relative motion between the lens and source is negligible. In this scenario, it is possible to temporally resolve the individual microimages. As a result, a method beyond the inverse ray shooting method, which only evaluates the total magnification of all microimages, is needed. We therefore implement an algorithm for identifying individual microimages and computing their magnifications and relative time delays. We validate our algorithm by comparing to analytical predictions for a single microlens case and find excellent agreement. We show that the superposition of pulses from individual microimages produces a light curve that appears as multipeaked FRBs. The relative time delays between pulses can reach 0.1–1 ms for stellar-mass lenses and hence can already be resolved temporally by current facilities. Although not yet discovered, microlensing of FRBs will become regular events and surpass the number of quasar microlensing events in the near future when 104−5 FRBs are expected to be discovered on a daily basis. Our algorithm provides a way of generating the microlensing light curve that can be used for constraining stellar-mass distribution in distant galaxies.

EXPRESS: High-Resolution Fourier Transform Infrared (FT-IR) Spectroscopic Imaging for Detection of Lung Structures and Cancer-Related Abnormalities in a Murine Model

Label-free molecular imaging is a promising utility to study tissues in terms of the identification of their compartments as well as chemical features and alterations induced by disease. The aim of this work was to assess if higher magnification of optics in the FTIR microscope coupled with the focal plane detector (FPA) resulted in better resolution of lung structures and if the histopathological features correlated with clustering of spectral images. FTIR spectroscopic imaging was performed on paraffinized lung tissue sections from mice with optics providing a total magnification of 61× and 36×. Then, IR images were subjected to unsupervised cluster analysis and, subsequently, cluster maps were compared with hematoxylin and eosin staining of the same tissue section. Based on these results, we observed minute features such as cellular compartments in single alveoli and bronchiole, blood cells and megakaryocytes in a vessel as well as atelectasis of the lung. In the case of the latter, differences in composition were also noted between the tissue from the non-cancerous and cancerous specimen. This study demonstrated the ability of high-definition FTIR imaging to evaluate the chemical features of well-resolved lung structures that could complement the histological examination widely used in animal models of disease.

THE PHARMACOLOGICAL ACTION OF CHOLINERGIC SUBSTANCES ON NEW CORNEAL BLOOD VESSELS IN RATS

This study aimed to evaluate the existence of muscarinic receptors in the new corneal blood vessels, experimentally induced with ketamine in rat pups. The experimental model of neovascularization was performed on 15-day-old Wistar rats, in which 5 intraperitoneal injections of ketamine were administered at a dose of 150 mg/kg body weight at 5-day intervals. Examination of the reactivity of new corneal blood vessels was performed on day 45 of life. Each eye that developed neovascularization was evaluated with a Nikon stereomicroscope, coupled to a Mshot video camera, and the total magnification of the system was 400X. The vascular diameter was measured at a chosen point, the same point /points for each recording made to that eye, and the acquisition of images was performed at set time intervals, every 60 seconds for each eye to be examined, throughout the recording period. The parameters under investigation were the variations of the vascular diameter, and the processing of the obtained data was performed with the help of Microsoft Office Excel. Our results suggest that muscarinic receptors are present in the new corneal blood vessels because the administration of conjunctival instillations of acetylcholine caused statistically significant vasodilation, while atropine, a blocker of muscarinic receptors, antagonized this effect.

Weak gravitational lensing Schwarzschild-MOG black hole in plasma

This paper is devoted to study weak gravitational lensing properties around black hole surrounded plasma medium in modified gravity (MOG). We have investigated the effects of the MOG-parametr and plasma medium on the deflection angle and total magnification of the images. we have presented the comparisons of the effects of the uniform plasma, singular isothermal sphere and non-singular isothermal sphere. We have also shown that the uniform plasma effects significantly stronger than the other models of plasma medium.Through the studies of the total magnifications of images of a remote source we have shown that the effects of the MOG parameter and plasma medium are similar and the increase of the MOG parameter and plasma frequency cause to increase the total magnification. Moreover, we have explored and analyzed how the MOG effects can reflect the plasma medium providing the same values of the total magnification of images.

Vacuum Brans–Dicke theory in the Jordan and Einstein frames: Can they be distinguished by lensing?

Vacuum Brans-Dicke (BD) theory continues to receive widespread attention since it is consistent with solar and cosmological experiments. The theory can be self-consistently described in two frames, the Jordan frame (JF) and the conformally rescaled Einstein frame (EF), the transformations providing an easy passage from one frame to the other at the level of actions and solutions. While coordinate transformations do not change curvature properties, conformal transformations do change them leading to corresponding changes in the numerical values of observables. A previous article by Bhadra et al.[Formula: see text] did exemplify this change between JF and EF using the diagnostic of second-order light deflection. This important work leaves room for further improvements on two points, which we do here. First, the measurement of second-order effect faced technically unsurmountable difficulties even around the Sun, hence actually abandoned. Second, the comparison of quantitative values between JF and EF should be based on a common value of [Formula: see text] connecting the two frames. Keeping these in mind, we investigate a technically easier diagnostic, viz., the weak field lensing (WFL) and compare the quantitative changes at common [Formula: see text] to show that the two frames can indeed be distinguished by lensing experiments. Specifically, the predictions of light deflection, image position, total magnification and magnification factor are computed in the EF and compared with those recently obtained (by Gao et al.[Formula: see text]) directly in the JF BD class I solution. The use of the value of BD coupling constant [Formula: see text], suggested by the Cassini spacecraft solar experiment, reveals that an exceptionally high degree of accuracy is needed to experimentally rule out one or the other frame by means of WFL measurements.

Addition of Illuminator Fiber Optic to Produce 3 Dimension Effects in Micrographic Observation Using Upright Microscope

Microscope is one of the tools used in practicums with high intensity. The use of a microscope adjusts to the object to be observed in order to obtain optimal micrographic results. Stereo microscopes are used to observe three-dimensional objects. Upright microscopes are used to observe two-dimensional objects. This study aims to combine the two advantages of stereo microscopy that can produce three-dimensional micrography with the advantages of an upright microscope that has a high total magnification. The method used in this study is an experimental method by adding an optical fiber illuminator in the use of an upright microscope and then applying it in various observations. The conclusion of this research is the addition of an optical fiber illuminator in observations using an upright microscope can replace the function of a stereo microscope; can produce three-dimensional effects and increase magnification in Daphnia magna micrographic observations.

Inventory of Gastrointestinal Endoparasitic Worms of Skipjack Tuna (Katsuwonus pelamis) in Sibolga Waters

of endoparasitic worms in skipjack tuna (Katsuwonus pelamis) in Sibolga Waters. Sampling conducted in Debora Private Fishing Port, Sibolga for 20 fishes that object weighing 740 – 1200 gr and length within 37,2 – 41,4 cm. The identification process is carried out in the laboratory using a microscope 40x and 100x total magnification. The endoparasitic worms found are Echinorhynchus sp. (100% intestinal and 10% stomach insidences, 8,6 intensities), Acanthocephalus sp. (25% Intestinal insidences, 1,6 intensities), Rhadinorhynchus sp. (25% intestinal and 5% stomach insidences, 1,5 intensities), Leptorhynchoides sp. (25% intestinal insidences, 1 intensity), Neoechinorhynchus sp. (25% intestinal insidences, 1,4 intensities), Pomphorhynchus sp. (10% intestinal insidences, 1,5 intensities), and Apororhynchus sp. (10% intestinal insidences, 1 intensity).

The results of the research of sandstones closed porosity

The article presents the results of the study of gas inclusions in quartz grains of Donets Basin sandstones. It describes the main genetic types of inclusions, their conditions of formation, shape, size, as well as features of the transformation under the conditions of catagenesis of rocks.The presence and distinctive features of the primary and secondary inclusions were established by studying of their homogenization temperatures. Thanks to these studies, it was found that the homogenization temperature of the primary inclusions is 1.5–2 higher than for secondary ones. Also, characteristic of the primary inclusions is that they are mainly gas-liquid. In size, primary inclusions are 1.5–2 times larger than secondary ones, and on average they are 2–3 µm. Secondary inclusionsessentially consist of gas. A characteristic feature of secondary inclusions in quartz grains of the sandstones of the Donetsk Basin is that they decorate the microdeformations of these grains, thereby forming numerous Boehm stripes. The gas inclusions of Boehm strips are indicators of paleotemperature, and the Boehm strips themselves carry information about paleopressure. To calculate the volume of gas inclusions, a methodwas proposed.This method is easy to use and does not require significant financial expenses. For its implementation, standard petrographic thin sections are used, which are examined using an optical microscope with a total magnification of 1000-1200 times. Using the proposed method, the volumes of gas inclusions in quartz grains of sandstones of different substages of catagenesis were established. Considering that gas inclusions are part of closed porosity, it is proposed to conditionally subdivide closed porosityinto cement closed porosity (volume of closed pores in the cementing substance of the rock) and grain closed porosity (volume of closed pores in detrital grains of the rock). It is established that the indicator of grain closed porosity is 2-3 times higher than the indicator of cement closed porosity. The largest volumes of gas inclusions are established for the middle substage of catagenesis. Considering that rock and gas outbursts occur only at the middle substage of catagenesis, this confirms the theory about the additional effect of gas inclusions on the progress of gas-dynamic phenomena in mine opening.Also, duringthe determination of absolute porosity of rocks in laboratory conditions, it is very important to grind the rock to micron-sized fraction. This will allow opening a part of inclusions in the clastic grains of rocks, which will substantially complement the indexes of absolute porosity.

A Note on the Overall Magnification of a Gravitational Point-Source—Point-Lens System

The total magnification due to a point lens has been of particular interest as the theorem that gravitational lensing results in light amplification for all observers appears to contradict the conservation of photon number. This has been discussed several times, and various resolutions have been offered. In this note, we use a kinematic approach to provide a formula for the magnification factor for the primary image accurate to first order and valid for rays leaving the source at any trajectory. We thus determine the magnification over a sphere surrounding the system. A new result found is that while the magnification dips below unity far from the optical axis as noted by others, it returns to unity directly behind the source.