Dusty space plasma diagnosis using temporal behavior of polar mesospheric summer echoes during active modification

The objective of this paper is to study the effect of different plasma and dust parameters on Polar Mesospheric Summer Echoes (PMSE) temporal behavior after turn-on and turn-off of radio wave heating and to use these responses to diagnose the properties of the dust layer. The threshold radar frequency and dust parameters for the enhancement or suppression of radar echoes after radio wave heating turn-on are investigated for measured mesospheric plasma parameters. The effect of parameters such as the electron temperature enhancement during heating, dust density, dust charge polarity, ion-neutral collision frequency, electron density and dust radius on the temporal evolution of electron irregularities associated with PMSE are investigated. The possible diagnostic information for various charged dust and background plasma quantities using the temporal behavior of backscattered radar power in active experiments is discussed. The computational results are used to make predictions for PMSE active modification experiments at 7.9, 56, 139, 224 and 930MHz corresponding to existing radar facilities. Data from a 2009 VHF (224 MHz) experiment at EISCAT is compared with the computational model to obtain dust parameters in the PMSE

Altered Immune Responses in Mice After Receiving Nicotine-pulsed Mesenchymal Stem Cell-conditioned Medium

Introduction: Previous investigations have documented that nicotine-pulsed mesenchymalstem cells (MSCs) can induce an anti-inflammatory phenotype in some immune cells in vitro.This study aimed to assess the effects of nicotine-pulsed MSCS in the function of immunecells, macrophages, and lymphocytes of mice receiving these cels.Materials and Methods: Bone marrow-derived MSCs (1.5×106) were seeded in a T75flaskand incubated with 0, .1, .5, or 1 μM nicotine until the cells reached 90% confluency.Afterwards, immunophenotyping change, vitality, concentration of TGF-β, IL-10, and IDOlevels of the MSC-conditioned medium were examined. Correspondent to in vitro results, theC57BL/6 mice intravenously received 400 μL of the conditioned medium of MSCs (CM),conditioned medium of nicotine (.5 μM)-pulsed MSCs (CMN), or medium. After 12 h, thelymphocytes, neutrophils, and peritoneal macrophages of the mice were isolated and theirfunction was evaluated ex vivo.Results: The least effective dose concentration of nicotine that led to an anti-inflammatoryenvironment by the MSC-conditioned medium was 0.5 μM. Nicotine at this concentrationprompted a higher level of TGF-β, IDO concentration in the conditioned medium. However,this concentration did not affect the MScs’ markers expressions or MScs’ vitality. T lymphocytesisolated from the mice receiving CMN showed a significant decrease in proliferation rate. Theratio of the IFN-γ gene expression to IL-4 gene expression in splenocytes was significantlyreduced in the mice receiving CMN compared to the mice receiving CM. The neutral reduptake, respiratory burst, and nitric oxide production of the peritoneal macrophage onlydecreased in the mice treated with CMN. These factors also decreased in neutrophils isolatedfrom mice receiving CM or CMN. However, these decreases were more prominent in the micetreated with CMN.Conclusion: Treatment of MSCs by nicotine may be a promising strategy to enhance theimmunomodulatory properties of these cells

Global simulations of multi-frequency hf signal absorption for direct observation of middle atmosphere temperature and composition

This paper presents the first numerical study on a new concept for the direct measurement of D-region absorption in the high-frequency (HF) band. Numerical simulations based on the Appleton-Hartree and Garrett equations of refractive index are presented. Electron temperature as a result of HF radio pumping of the ionosphere is included in the calculations using proper numerical formulation. Both O- and X-mode radio wave polarizations are taken into consideration. A global map of HF absorption in the northern hemisphere is calculated. Detailed calculations of HF radio wave absorption as it propagates through the lower atmosphere are presented. The effect of several parameters on the amount of absorption is calculated. The best frequencies to be used for the purpose of this study are discussed. A machine learning model is developed and the capability of the model in estimation of D and E-region constituents includes N2, O, O2, as well as T and Ne is examined. Such a technique can also lead to global mapping of HF absorption and improve OTHR (over-the-horizonradar) performance

Modulation of polar mesospheric summer echoes (PMSEs) with high-frequency heating during low solar illumination

Polar mesospheric summer echo (PMSE) formation is linked to charged dust/ice particles in the mesosphere. We investigate the modulation of PMSEs with radio waves based on measurements with EISCAT VHF radar and EISCAT heating facility during low solar illumination. The measurements were made in August 2018 and 2020 around 20:02 UT. Heating was operated in cycles with intervals of 48 s on and 168 s off. More than half of the observed heating cycles show a PMSE modulation with a decrease in PMSE when the heater is on and an increase when it is switched off again. The PMSE often increases beyond its initial strength. Less than half of the observed modulations have such an overshoot. The overshoots are small or nonexistent at strong PMSE, and they are not observed when the ionosphere is influenced by particle precipitation. We observe instances of very large overshoots at weak PMSE. PMSE modulation varies strongly from one cycle to the next, being highly variable on spatial scales smaller than a kilometer and timescales shorter than the timescales assumed for the variation in dust parameters. Average curves over several heating cycles are similar to the overshoot curves predicted by theory and observed previously. Some of the individual curves show stronger overshoots than reported in previous studies, and they exceed the values predicted by theory. A possible explanation is that the dust-charging conditions are different either because of the reduced solar illumination around midnight or because of long-term changes in ice particles in the mesosphere. We conclude that it is not possible to reliably derive the dust-charging parameters from the observed PMSE modulations

Global simulations of multi-frequency HF signal absorption for direct observation of middle atmosphere temperature and composition

The model used in the publication for Global simulations of multi-frequency HF signal absorption for direct observation of middle atmosphere temperature and composition This paper presents the first numerical study on a new concept for the direct measurement of D-region absorption in the HF band. Numerical simulations based on the Appleton–Hartree and Garrett equations of refractive index are presented. Electron temperature as a result of HF radio pumping of the ionosphere is included in the calculations using proper numerical formulation. Both O- and X-mode radio wave polarizations are taken into consideration. A global map of HF absorption in the northern hemisphere is calculated. Detailed calculations of HF radio wave absorption as it propagates through the lower atmosphere are presented. The effect of several parameters on the amount of absorption is calculated. The best frequencies to be used for the purpose of this study are discussed. A machine learning model is developed and the capability of the model in estimation of D and E-region constituents includes $N_2$, $O$, $O_2$, as well as $T$ and $N_e$ is examined. Such a technique can also lead to global mapping of HF absorption and improve OTHR (over-the-horizon-radar) performance

Soil evolution along an alluvial-loess transect in the Herat Plain, western Afghanistan

Afghanistan is located in the Eurasian loess belt, however, there is little information on the soils in the area. Loess has covered the Herat Plain in western Herat City, Afghanistan. Despite the diversity of landform and parent material, there is no information on the soil and landform evolution in this area. The objectives of this study were to identify the soils along a transect of different landforms in the Herat Plain and determine the role of geomorphic processes on the soil and landform evolution. Five pedons from an alluvial fan, the depression between alluvial fan and piedmont plain, saline and non-saline piedmont plains, and the flood plain of the Hariroud River, were sampled. Then, the physical-chemical properties, mineralogy, and micromorphology of the samples were determined. Results showed that the soil parent material in the piedmont plain is loess, whereas, in the flood plain it is a combination of loess and river alluvial sediments. Calcification, lessivage, salinization, and gleization are the most important pedogenic processes. The calcification and lessivage appear to be the result of a wetter climate during the late Quaternary, whereas the present topography causes the gleization and salinization. Clay coatings on carbonate nodules and iron nodules are abundant pedofeatures in the Btk (argillic-calcic) horizon. Iron oxides nodules are common in the soils of the flood plain. The formation of palygorskite in both alluvial-and loess-derived soils implies the onset of aridity and the trend of increase in environmental aridity in the region. It seems that after the formation of a well developed paleosol on the alluvial fan in a more humid climate in the past, the piedmont plain has been covered by loess deposits, and the calcification, gleization, and salinization cause the formation of weakly developed surficial soils. This study highlights the role of the late Quaternary climatic changes on the evolution of landforms and soils in western Afghanistan

The effect of morphine administration on structure and ultrastructure of uterus in pregnant mice

Background: Maternally administered opiates such as morphine represent a serious human health problem. Opioid abuse may have unfavorable effects on reproductive organs. Objective: The present study evaluates on the effects of morphine on structure and ultrastructure of uterus in BALB/c mice. Materials and Methods: Forty BALB/c pregnant mice were divided into four groups: two experimental (I and II), one sham and one control group. 5 mg/kg and 10 mg/kg morphine were injected via intra-peritoneal (IP) route, daily (during 15 days) in group I and II animals, respectively. The same volume of saline was administrated in sham group. Control group did not receive any treatment. At 15th day of gestation (E15), the pregnant mice were sacrificed and their uterus was removed. Following histochemical staining, the samples were studied using light and transmission electron microcopies. Results: In experimental groups, some apoptic sites with polymorphic inflammatory infiltration and congestion of vessels were observed. The rate of polymorphic inflammatory infiltration and apoptic sites were 60% and 70% in experimental groups I and II, respectively. Also, the rate of vessel congestion in the experimental groups (I and II) was 70%. The ultrastructural study showed the nuclear membranes of endometrial epithelial cell was torn, convoluted, and a distance between nuclei and irregular chromatin was observed in both experimental groups. There were no signs of structural abnormalities in other groups. Conclusion: Morphine administration causes histological and cytological lesions that may be responsible for endometrial alterations in laboratory animals

Wheeler's Family and Euphrates College

Ankara : İhsan Doğramacı Bilkent Üniversitesi İktisadi, İdari ve Sosyal Bilimler Fakültesi, Tarih Bölümü, 2017.This work is a student project of the The Department of History, Faculty of Economics, Administrative and Social Sciences, İhsan Doğramacı Bilkent University.by Feyzullahoğlu, Burcu

Conformity of Nursing Clinical Courses with Nursing Job Responsibilities in Tabriz University of Medical Sciences

Introduction: One of the problems of nursing education is the conformity of clinical training with nursing job responsibilities. Therefore, the purpose of this study was to assess the conformity of clinical courses of nursing students with nursing job responsibilities from the perspective of temporary employed nurses in Tabriz University of Medical Sciences. Methods: This descriptive study was conducted in 2015. All temporary employed nurses working in 5 teaching hospitals of Tabriz were selected through census method. The sample size was equal to the whole population (145 people). All of the subjects except those who were absent for more than a month in the center were included in the study. Data were collected by a valid and reliable researcher-made questionnaire to assess the conformity of 9 clinical courses. Scores were coded as 1 (very low), 2 (low), 3 (high) and 4 (very high). Descriptive statistics were used to analyze the data. Results: The conformity rates of the nursing clinical courses with clinical responsibilities were 89.69% for nursing principles and skills, 74.48% for community health nursing, 88.03% for health status evaluation, 68.54% for maternity and newborn health, 80.79% for pediatric nursing, 72.13% for medical-surgical nursing, 77.11% for critical care nursing, 77.68% for emergencies and disasters nursing, 77.68 and 75.41% for mental health nursing. These rates were evaluated at very high and high levels. Conclusion: For higher conformity of the courses with the clinical responsibilities of the curriculum, it is recommended that nursing education planners should comprehensively review and revise the syllabus and clinical learning model

Investigation of Salt and precipitating agent effect on the specific surface area and compressive strength of alumina catalyst support

Nowadays, catalyst supports are extensively used to decrease the costs and increase the contact surface area in chemical reactions. Specific surface area, compressive strength, pore volume and pore size are some of the most important characteristics of a catalyst support. In this work, Sol-gel and peptization methods were applied to produce alumina catalyst support. Also the roles of aluminum salts and precipitating agents on the specific surface area and compressive strength of alumina catalyst support were investigated. In addition, various additives and common methods in the increasing surface area, compressive strength and adjusting the porosity and pore size are used in this study. The results show that using caustic soda as precipitating agent and aluminum chloride salt yields catalyst supports with the best compressive strength. Also, using aluminum nitrate and ammonia as precipitating agent produced alumina catalyst support with the highest specific surface area