NEARBY INTERACTING GALAXY PAIRS: DYNAMICS AND IONIZED GAS PROPERTIES

Galaxy merging is an important process in galaxy formation and evolution throughout the cosmic time. Mergers are expected to play a significant role in galaxy mass assembly and transformation of galaxy morphology. In this work, we study inter- acting pairs of galaxies in a relatively early stage of the merging process, after they first pass by each other but before they coalesce into a single galaxy. At this stage, interacting disk galaxies display peculiar morphologies, often induced by the strong gravitational tidal field experienced during the first passage. These peculiar features can be utilized to constrain the encounter parameters of the merging galaxies, such as time since first passage, and pericentric separation (Toomre & Toomre, 1972; Hi- bbard & Mihos, 1995; Barnes & Hibbard, 2009). Moreover, in the early stages of galaxy mergers the individual galaxies are still clearly separated making it possible to investigate the chain of physical processes that are caused by the interaction. This includes starbursts or active galactic nuclei (AGNs) triggered by the infall of gas into the cores (Mihos & Hernquist, 1996; Hopkins & Quataert, 2011), and the shocks that are produced by feedback from starbursts and AGNs (Cox et al., 2006b; Narayanan et al., 2008; Rich et al., 2015), or by collision of gaseous clouds in the interstellar medium (ISM) of the two disks as they pass through each other (Struck, 1997). We develop a novel automated method for modeling the dynamics of equal mass galaxy mergers that puts meaningful constraints on the system’s encounter parameters. In order to understand the systematics of the measured encounter parameters, we test our method against an independent set of galaxy merger simulations with known initial conditions. For a controllable subset of these tests, our automated method recovers parameters such as merger stage and initial disk orientations within 3σ of the correct value. We explore the effects of using different kinematic tracers on the inferred encounter parameters by applying our method to HI and Hα velocity maps of a well-studied galaxy merger system in the nearby Universe, NGC 4676 a.k.a the Mice galaxies. We show for the first time that constraints on the encounter parameters derived from HI and Hα kinematics are consistent suggesting that Hα velocity maps can also be used for dynamical modeling. In total we observe a sample of 22 galaxy mergers in this work. Nineteen of them have morphological indicators similar to the Mice galaxies (separate cores and strong tidal features), and the other three are recently coalesced systems where cores are united, but outskirts are still disturbed. We use SparsePak integral field unit (IFU) (Bershady et al., 2004) on the WIYN telescope at Kitt Peak National Observatory (KPNO) to observe the Hα emission over the entire visible regions of these galaxies, including faint tidal tails. Relatively high spectral resolution of our data allows us to investigate multiple kinematic components in the emission lines. We separate Hα emission of photo-ionized HII regions from shocked gas, measure the velocity maps of HII regions, and discuss the fraction and spatial distribution of shocks and their power source. We apply our dynamical modeling method on equal mass systems in our sample and obtain the first ever constraints on the encounter parameters of one of them. We find a trend between shocked gas fraction and the projected separation between the galaxies in pairs, similar to Rich et al. (2015). In our sample of interacting pairs, for the first time, we also find a trend between shocked gas fraction and the light ratio (mass ratio). These trends suggest that in most of the observed systems the gravitational tidal impulse at the time of the first passage is the dominant origin of shocks. Also for the first time, we investigate the correlation between shocked gas fraction and encounter parameters from dynamical modeling. We find that time until coalescence and pericentric separation are both strongly anti-correlated with the amount of shocks. However, larger statistical sample is required for understanding the physical details and timing of shock production during galaxy mergers. Clean separation of shocks from star forming regions also improves the accuracy of star formation rate measurements in merging galaxies. Large ongoing and upcoming IFU galaxy surveys such as MaNGA (Bundy et al., 2015) will provide spatially resolved spectra of large numbers of galaxies including many galaxy mergers. Tools and techniques developed for this thesis project are required steps for better utilization of these valuable datasets

Formulation and Evaluation of Lorazepam Orally Disintegrating Tablet

Introduction: oral dosage forms are the safest, the most convenient and the most economical method of drug delivery system in the pharmaceutical industry but, in geriatric and pediatric patients who have swallowing difficulty and in the emergency situations, we need the fastest therapeutic effects on conventional oral drug delivery because  of time issue. To troubleshoot? such problems a new dosage form known as orally disintegrating tablets (ODT) can be useful and more effective. Lorazepam is  a benzodiazepine drug that stimulates GABA receptor and is used in the prevention of panic attack, management of anxiety disorders, treatment of status epilepticus andetc. Based on these details, ODT form of Lorazepam can be helpful for geriatric and pediatric patients and also handling emergency situations. Methods and Results: In this study, various formulations were designed and prepared by using direct compression method. All of our formulations contained 2 mg of Lorazepam as API. We used 3 differences bulking agents (mannitol, lactose, avicel) and the percentages of disintegrating agent (5%, 10%, 15% of crosscarmelose).then, for examining our formulations and choosing the best formulation we carried out or conducted physicochemical tests like flowability of powder, tablet appearance, thickness, uniformity of weight, hardness, friability and disintegration time. Finally, one of these formulations (lactose as bulking agent and 10% crosscarmelose as disintegrating agent) which showed optimum physicochemical properties was selected for further studies. Conclusions:  regarding our study and literatures, we attempted to evaluate a novel formulation of Lorazepam ODT. physicochemical test results showed this formulation  ideal for developing new dosage forms of Lorazepam for resolving some of the patient's problems

An Investigation into the Effect of Various Penetration Enhancers on Percutaneous Absorption of Piroxicam

Abstract Achieving a desirable percutaneous absorption of drug molecule is a major concern in formulating dermatological products. The use of penetration enhancers could provide a successful mean for this purpose. The aim of this study was to evaluate the effect of incorporating a few common penetration enhancers (in different concentrations) into a 0.5% w/w piroxicam (model drug) gel formulation, on the permeability rate of drug through rat abdominal skin in vitro. For this purpose various concentrations of oleic acid (OA), urea (UR), lecithin (LEC) and isopropyl myristate (IPM) were used as the penetration enhancer. In order to investigate the effect of penetration enhancers used in this study on the permeability rate of piroxicam through sections of excised rat skin, Franz-type diffusion cells were employed. The receptor phase was constantly stirring 0.9% w/v sodium chloride solution at 32°C. At set intervals up to 8h, 5ml samples were removed from the receptor compartment and the amount of piroxicam permeated through the skin calculated by determining the UV absorbance of drug at 353 nm. Results show that among the penetration enhancers used, the use of OA at a concentration of 1.0% w/w had the greatest effect on the permeability rate of piroxicam, and produced the highest enhancement ratio among all the penetration enhancers examined. The other penetration enhancers used were found to have a far smaller effect on the permeability rate of piroxicam through rat skin. The enhancement ratio of the penetration enhancers used in the formulation of piroxicam gel were found to increase in the order of OA>> IPM > LEC > UR

The Effect of Elaeagnus angustifolia L. Cream on Radiation-Induced Skin Reactions in Women with Breast Cancer; A Preliminary Clinical Trial: Running title?????

Radiotherapy, a highly effective way to destroy breast cancer, causes skin adverse effects. A considerable amount of studies have been conducted to find a way to alleviate or relieve dermal adverse effects of radiation. The aim of this study was to observe the clinical effect of Elaeagnus angustifolia L. cream to treat radiotherapy-induced skin destruction in breast cancer patients.Thirty two patients suffering from different stages of radiotherapy-induced skin reactions were evaluated in a double-blind randomized study; 16 patients in the treatment group received Elaeagnus angustifolia cream, while the other 16 patients, served as control group.Two weeks after the treatment, patients in Elaeagnus angustifolia group showed significantly lower skin reaction grade compared with placebo group. The attitude of the patients of Elaeagnus angustifolia group about dryness, itching, pain, burning, blisters and sores was significantly improved after two weeks of treatment.Elaeagnus angustifolia cream may effectively reduce the radiotherapy-induced dermal injury

How Reactivation of SARS-CoV-2 in Astronauts with Dysregulated Immune Systems Can Negatively Affect the Odds of Success in Future Space Missions

We have previously reported that during future space missions the risk of severe COVID-19 infection will be a cardinal issue that needs careful attention. Our studies show that even with the most reliable pre-mission screening and quarantine strategies, astronauts with a latent (hidden, inactive, or dormant) SARS-CoV-2 infection might be sent to space. Given this consideration, an asymptomatic individual with dormant SARS-CoV-2 infection may successfully pass all the pre-launch medical tests. Then during a space mission such as a journey to Mars or beyond, when the immune system of these astronauts starts to weaken, the dormant infection may progress to a severe infection that possibly affects the chance of the mission’s success. The effects of microgravity and the elevated space radiation are two key factors that should be evaluated. Furthermore, the limited size of the spacecraft, the proximity of crew members during flight operations, spacecraft atmospheric composition, limited exercise capability, effects of viral response to space radiation, and uncertainty in the likelihood of the virus to mutate and evolve during a space mission merit additional study

Evaluating the Strength of a Hypothesis on How Terrestrial Organisms Overcame the Loss of Water’s Protective Shield

Evaluating the Strength of a Hypothesis on How Terrestrial Organisms Overcame the Loss of Water’s Protective Shield Evaluating the Strength of a Hypothesis on How Terrestrial Organisms Overcame the Loss of Water’s Protective Shield Evaluating the Strength of a Hypothesis on How Terrestrial Organisms Overcame the Loss of Water’s Protective Shield Evaluating the Strength of a Hypothesis on How Terrestrial Organisms Overcame the Loss of Water’s Protective Shiel

shRNA-mediated downregulation of α-N-Acetylgalactosaminidase inhibits migration and invasion of cancer cell lines

Objective(s): Extracellular matrix (ECM) is composed of many kinds of glycoproteins containing glycosaminoglycans (GAGs) moiety. The research was conducted based on the N-Acetylgalactosamine (GalNAc) degradation of ECM components by α-N-acetylgalactosaminidase (Nagalase) which facilitates migration and invasion of cancer cells. This study aims to investigate the effects of Naga-shRNA downregulation on migration and invasion of cancer cell lines. Materials and Methods: In this study, MCF-7 cell line (human mammary carcinoma cell line) and A2780 (human ovarian carcinoma cell line) were used. The level of normalized Naga expression and Nagalase protein were evaluated by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay/western blotting, respectively. Migration and invasion were determined using transwell assays, and statistical analysis was carried out by ANOVA test. Results: Response to transduction by shRNA compared to the control group, migrative and invasive properties of the transfected cells were significantly inhibited. Conclusion: These results indicate that Nagalase may have an important role in migration and invasion of cancer cells and can be considered as a candidate for further studies

An investigation on the effect of alcoholic and aqueous extracts of Dorema aucheri (Bilhar) on some pathogenic bacteria in vitro

       Dorema aucheri is a plant that grows in Iran. In Persian it is called (Bilhar). This experimental study was carried out at Ferdowsi University of Mashhad in 2014. After collection and preparation of aqueous and ethanolic extracts of Dorema aucheri (Bilhar), The antibacterial activity of ethanolic and aqueous extracts of Bilhar was evaluated against 7 laboratory strains of microorganisms, including 4 Gram positive (Staphylococcus aureus, Streptococcus pyogenes, Bacillus cereus and Bacillus subtilis) and 3 Gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa and Proteus vulgaris). Its effects against human pathogen microorganism were determined using “Spreading of the Extract on Medium Surface” and “Disk Agar Diffusion Method”, Minimal Inhibitory Concentration (MIC) and Minimum Lethal Concentration (MLC) were determined for this extract. Collected data were analyzed by SPSS software using one-way ANOVA. The zone of inhibition for the ethanolic extract varied from 8 mm for P. aeruginosa to 24 mm for S. pyogenes and from 7 mm for P. aeruginosa to 19 mm for S.pyogenes in the aqueous extract. The minimum inhibitory concentration (MIC) of the extracts ranged between 2 mg/ml and 64 mg/ml while the minimum lethal concentration (MLC) ranged between 4 mg/ml and 256 mg/ml. Among of tested strains, P. aeruginosa has maximum MIC and MBC. 30 and 40 mg/mL Concentrations of Redcurrant have significant antimicrobial effect on bacteria. Antibacterial effect of extracts was decreased with decrease of extract concentration in disk. According to result, ethanolic extract of Dorema aucheri have antimicrobial effect on growth of all of the strains exposed analyzes and antimicrobial effect of that was maximum on Gram-positive bacterum of S. pyogenes. P. aeruginosa showed the highest level of resistance against the aqueous and ethanolic Bilhar extracts. The present study demonstrated that the ethanol leaf extract of Dorema aucheri hold an excellent potential as an antibacterial agent.

Analysis of different signal peptides for the secretory production of Ama r 2 in gram-positive systems (Lactococcus lactis)

Prokaryotic systems have been considered the most affordable and simplest hosts which are being employed to express recombinant proteins such as allergens; nevertheless, without appropriate signal peptide (SP), these systems cannot be used for secretory proteins. Recently, a lot of effort has been put into assessing the potential of gram-positive strains such as lactic acid bacteria for new applications in the production of heterologous proteins. Ama r 2 is a respiratory allergen from Amaranthus retroflexus, whose recombinant production in the probiotic host could be introduced as a specific and effective way to rapid diagnosis and immunotherapy of this allergy. Consequently, the production of this recombinant protein using the prokaryotic system, requires a suitable SP to protect disulfide bonds and to prevent misfolding. This study was designed to predict the best SPs for the expression of Ama r 2 protein in Lactococcus lactis as the host. In this study, 42 signal sequences were selected from SP databases and the most important features of them were evaluated. First, n, h and c regions of the SPs and their probabilities were investigated by signalP software version 4.1. Then, their physicochemical properties were evaluated by Portparam and SOLpro. Moreover, the secretion sorting and sub-cellular localization sites were evaluated by PRED-TAT and ProtcompB software programs. The results revealed that yjgB, entC2 (Entrotoxine type C-2), ent B (Entrotoxine type), blaZ (Beta lactamase), dex (number 21), blm (Beta lactamase 2), dex (Dextranase; number 20) and number 26 were introduced theatrically as the best SPs to express Ama r 2 in Lactococcus lactis

Sensitivity to Antibiotics of Bacteria Exposed to Gamma Radiation Emitted from Hot Soils of the High Background Radiation Areas of Ramsar, Northern Iran

Background: Over the past several years our laboratories have investigated different aspects of the challenging issue of the alterations in bacterial susceptibility to antibiotics induced by physical stresses. Objective: To explore the bacterial susceptibility to antibiotics in samples of Salmonella enterica subsp. enterica serovar Typhimurium (S. typhimurium), Staphylococcus aureus, and Klebsiella pneumoniae after exposure to gamma radiation emitted from the soil samples taken from the high background radiation areas of Ramsar, northern Iran. Methods: Standard Kirby-Bauer test, which evaluates the size of the zone of inhibition as an indicator of the susceptibility of different bacteria to antibiotics, was used in this study. Results: The maximum alteration of the diameter of inhibition zone was found for K. pneumoniae when tested for ciprofloxacin. In this case, the mean diameter of no growth zone in non-irradiated control samples of K. pneumoniae was 20.3 (SD 0.6) mm; it was 14.7 (SD 0.6) mm in irradiated samples. On the other hand, the minimum changes in the diameter of inhibition zone were found for S. typhimurium and S. aureus when these bacteria were tested for nitrofurantoin and cephalexin, respectively. Conclusion: Gamma rays were capable of making significant alterations in bacterial susceptibility to antibiotics. It can be hypothesized that high levels of natural background radiation can induce adaptive phenomena that help microorganisms better cope with lethal effects of antibiotics