bluuebunny/crossref_metadata_2025 huggingface dataset:
Bifurcations, chaos, and multistability in a nonautonomous predator–prey model with fear
Authors: Hossain Mainul , Pal Saheb , Kumar Tiwari Pankaj , Pal Nikhil
Published: December 2021

Classical predator–prey models usually emphasize direct predation as the primary means of interaction between predators and prey. However, several field studies and experiments suggest that the mere presence of predators nearby can reduce prey density by forcing them to adopt costly defensive strategies. Adoption of such kind would cause a substantial change in prey demography. The present paper investigates a predator–prey model in which the predator’s consumption rate (described by a functional response) is affected by both prey and predator densities. Perceived fear of predators leads to a drop in prey’s birth rate. We also consider both constant and time-varying (seasonal) forms of prey’s birth rate and investigate the model system’s respective autonomous and nonautonomous implementations. Our analytical studies include finding conditions for the local stability of equilibrium points, the existence, direction of Hopf bifurcation, etc. Numerical illustrations include bifurcation diagrams assisted by phase portraits, construction of isospike and Lyapunov exponent diagrams in bi-parametric space that reveal the rich and complex dynamics embedded in the system. We observe different organized periodic structures within the chaotic regime, multistability between multiple pairs of coexisting attractors with intriguing basins of attractions. Our results show that even relatively slight changes in system parameters, perturbations, or environmental fluctuations may have drastic consequences on population oscillations. Our observations indicate that the fear effect alters the system dynamics significantly and drives an otherwise irregular system toward regularity.
Birds breathe at an aerodynamic resonance
Authors: Fainstein Facundo , Geli Sebastián M. , Amador Ana , Goller Franz , Mindlin Gabriel B.
Published: December 2021

We present a dynamical model for the avian respiratory system and report the measurement of its variables in normal breathing canaries (Serinus canaria). Fitting the parameters of the model, we are able to show that the birds in our study breathe at an aerodynamic resonance of their respiratory system. For different respiratory regimes, such as singing, where rapid respiratory gestures are used, the nonlinearities of the model lead to a shift in its resonances toward higher frequency values.
Sod1 integrates oxygen availability to redox regulate NADPH production and the thiol redoxome
Authors: Montllor-Albalate Claudia , Kim Hyojung , Thompson Anna E. , Jonke Alex P. , Torres Matthew P. , Reddi Amit R.
Published: December 2021

Significance

Cu/Zn superoxide dismutase (Sod1) is a key antioxidant enzyme, and its importance is underscored by the fact that its ablation in cell and animal models results in oxidative stress; metabolic defects; and reductions in cell proliferation, viability, and lifespan. Curiously, Sod1 detoxifies superoxide radicals (O2•−) in a manner that produces an oxidant as byproduct, hydrogen peroxide (H2O2). While much is known about the necessity of scavenging O2•−, it is less clear what the physiological roles of Sod1-derived H2O2are. We discovered that Sod1-derived H2O2plays an important role in antioxidant defense by stimulating the production of NADPH, a vital cellular reductant required for reactive oxygen species scavenging enzymes, as well as redox regulating a large network of enzymes.
Nutrient availability and senescence spatially structure the dynamics of a foundation species
Authors: Bell Tom W. , Siegel David A.
Published: December 2021

Significance

Landscapes are spatially heterogeneous, and the measurement of spatial pattern is dependent upon observation scale. Understanding plant populations requires assessing their extrinsic interactions with the environment as well as intrinsic biological processes and has been difficult because of the inability to track both plant abundance and health on appropriate scales. We introduce remote sensing observations that assess the abundance and health of giant kelp, an important ecosystem-structuring species, over regional and local scales. We find that both extrinsic nutrient availability and intrinsic senescence processes regulate population dynamics but on regional and local scales, respectively. This suggests that future satellite missions will be able to assess plant abundance and health and their interactions with the environment on local to global scales.
Deepfake detection by human crowds, machines, and machine-informed crowds
Authors: Groh Matthew , Epstein Ziv , Firestone Chaz , Picard Rosalind
Published: December 2021

Significance

The recent emergence of deepfake videos raises theoretical and practical questions. Are humans or the leading machine learning model more capable of detecting algorithmic visual manipulations of videos? How should content moderation systems be designed to detect and flag video-based misinformation? We present data showing that ordinary humans perform in the range of the leading machine learning model on a large set of minimal context videos. While we find that a system integrating human and model predictions is more accurate than either humans or the model alone, we show inaccurate model predictions often lead humans to incorrectly update their responses. Finally, we demonstrate that specialized face processing and the ability to consider context may specially equip humans for deepfake detection.
Modeling for COVID-19 college reopening decisions: Cornell, a case study
Authors: Frazier Peter I. , Cashore J. Massey , Duan Ning , Henderson Shane G. , Janmohamed Alyf , Liu Brian , Shmoys David B. , Wan Jiayue , Zhang Yujia
Published: December 2021

Significance

Decisions surrounding how to safely reopen universities directly impact 7% of the US population (students, staff) and indirectly impact tens of millions more (families, communities). After witnessing large COVID-19 outbreaks among students from August 2020 to the present, universities want to provide safety while minimizing social and financial costs, despite uncertainty about vaccine hesitancy, vaccine efficacy, more transmissible variants with the potential for immune escape, and community prevalence. When the Delta variant is dominant, we find substantial risk reduction in moving student populations from mostly (75%) to fully (100%) vaccinated, in testing vaccinated students once per week even when all students are vaccinated, and in more frequent testing targeted to the most social groups of students.
A virus-specific monocyte inflammatory phenotype is induced by SARS-CoV-2 at the immune–epithelial interface
Authors: Leon Juliette , Michelson Daniel A. , Olejnik Judith , Chowdhary Kaitavjeet , Oh Hyung Suk , Hume Adam J. , Galván-Peña Silvia , Zhu Yangyang , Chen Felicia , Vijaykumar Brinda , Yang Liang , Crestani Elena , Yonker Lael M. , Knipe David M. , Mühlberger Elke , Benoist Christophe
Published: December 2021

Significance

By modeling in vitro the cross-talk between epithelial and immune cells, this work provides possible origins for the profound inflammatory perturbations that are a hallmark of COVID-19, and the relative protection of children from severe disease. The initial interaction between immune cells and epithelial cells infected with SARS-CoV-2, or transduced to express the proteins the virus encodes, elicits a specific response, not observed with other pathogenic viruses, that presages perturbations seen in patients with severe COVID-19. Thus, the severe manifestations of COVID-19 may be rooted in the very first response that it elicits from immunocytes.
Deflections of dynamic momentum flux and electron diamagnetic thrust in a magnetically steered rf plasma thruster
Authors: Imai Ryoji , Takahashi Kazunori
Published: December 2021

Two-dimensional characterization of the plasma plume is experimentally performed downstream of a magnetically steered radiofrequency plasma thruster, where the ion beam current, the ion saturation current, and the horizontal dynamic momentum flux, are measured by using the retarding field energy analyzer, the Langmuir probe, and the momentum vector measurement instrument, respectively, in addition to the previously measured horizontal thrust. The measurements show the deflections of the dynamic momentum flux including both the ions and the neutrals; the change in the direction of the dynamic momentum flux is consistent with the previously measured horizontal thrust. Furthermore, the ion saturation current profile implies that the deflected electron-diamagnetic-induced Lorentz force exerted to the magnetic nozzle contributes to the change in the thrust vector. Therefore, it is demonstrated that the deflections of both the dynamic momentum flux and the electron-diamagnetic-induced Lorentz force play an important role in the thrust vector control by the magnetic steering.
Investigation of Ni catalyst activation during plasma-assisted methane oxidation
Authors: Li Yudong , Hinshelwood Michael , Oehrlein Gottlieb S
Published: December 2021

Atmospheric pressure plasma has shown promise in improving thermally activated catalytic reactions through a process termed plasma-catalysis synergy. In this work, we investigated atmospheric pressure plasma jet (APPJ)-assisted CH4 oxidation over a Ni/SiO2
.Al2O3 catalyst. Downstream gas-phase products from CH4 conversion were quantified by Fourier transform infrared spectroscopy. The catalyst near-surface region was characterized by in-situ diffuse reflectance infrared Fourier transform spectroscopy. The catalyst was observed to be activated at elevated temperature (500 °C) if it was exposed to the APPJ operated at large plasma power. ‘Catalyst activation’ signifies that the purely thermal conversion of CH4 using catalysts which had been pre-exposed to plasma became more intense and produced consistently CO product, even if the plasma was extinguished. Without the application of the APPJ to the Ni catalyst surface this was not observed at 500 °C. The study of different exposure conditions of the activated catalyst indicates that the reduction of the catalyst by the APPJ is likely the cause of the catalyst activation. We also observed a systematic shift of the vibrational frequency of adsorbed CO on Ni catalyst when plasma operating conditions and catalyst temperatures were varied and discussed possible explanations for the observed changes. This work provides insights into the plasma-catalyst interaction, especially catalyst modification in the plasma catalysis process, and potentially demonstrates the possibility of utilizing the surface CO as a local probe to understand the plasma-catalyst interaction and shed light on the complexity of plasma catalysis.
Comprehensive study on unipolar RRAM charge conduction and stochastic features: a simulation approach
Authors: Maldonado D , Gómez-Campos F M , González M B , Roldán A M , Jiménez-Molinos F , Campabadal F , Roldán J B
Published: December 2021

An in-depth analysis of resistive switching (RS) in unipolar devices is performed by means of a new simulator based on resistive circuit breakers of different features. The forming, set and reset processes are described in terms of the stochastic formation and rupture of conductive filaments (CFs) of several branches in the dielectric. Both, the electric field and temperature dependencies are incorporated in the simulation. The simulation tool was tuned with experimental data of devices fabricated making use of the Ni/HfO2/Si stack. The variability and the stochastic behavior are characterized and reproduced correctly by simulation to understand the physics behind RS. Reset curves with several current steps are explained considering the rupture of different branches of the CF. The simulation approach allows to connect in a natural manner to compact modeling solutions for the devices under study.
Performance recovery of plasma actuators in wet conditions
Authors: Lilley Alexander James , Roy Sarthak , Michels Lucas , Roy Subrata
Published: December 2021

Plasma actuators have been extensively studied for flow control applications over the past two and a half decades. While these studies have been traditionally focused on characterizing their performances as flow control devices, the performance of plasma actuators under adverse conditions such as dew or light rain remains to be less explored. This paper seeks to study the effects of water adhesion from droplets directly sprayed on to a plasma actuator using thrust recovery as the performance metric. It was found in all tests that wet actuators quickly recover plasma glow, before gradually regaining performance comparable to the dry actuator. The measured thrust for the wet actuator after 5 s of operation recovered by 46% and 42% of the thrust of the dry actuator for 50.0–62.5 g m−2 and 125–150 g m−2 of sprayed water droplets, respectively. At 22.5 kVpp and 14 kHz, the highest thrust recovery was recorded at 84% of that of the dry actuator after 80 s of operation. For 17.5 kVpp and 14 kHz the wet thrust recovered by 79%, while for 22.5 kVpp and 10 kHz the wet thrust recovered by 68% of their dry counterpart in 80 s. For 17.5 kVpp and 14 kHz, the thrust almost fully recovered in comparison to the dry actuator after about 290 s of operation. These results indicate that both applied voltage and operating frequency plays a critical role in the performance recovery while the latter may have a stronger influence. Performance recovery for a wet serpentine shaped plasma actuator is also included for general applicability. The power data in all cases show that wet actuators consume more power which with time gradually approach the dry actuator power data. This is because during the initial stages of operation, the rolling mean current of the wet actuator is higher than the dry actuator even though the ionization spikes of dry actuator is stronger.
Solutions of Schrodinger equation and thermodynamic properties of Iodine and Scandium Fluoride molecules based on Formula method
Authors: Njoku I J , Onyenegecha C P , Okereke C J , Omugbe E , Onyeocha E
Published: December 2021

The study presents the thermodynamic properties of the Iodine and Scandium Fluoride molecules with molecular Deng-Fan potential. The bound state energy solution of the radial Schrodinger equation is obtained via the formula method. The partition function and other thermodynamic properties are evaluated via the Poisson summation approach. The numerical values of energy of the I2 and ScF molecules are found to be in agreement with results obtained from other methods in the literature. The results further show that the partition function decreases, and then converges to a constant value as temperature increases.
Histological analysis of tattoo removal by water cavitation bubbles and jet formation using Nd: YAG and nanosecond laser pulses
Authors: Hamoudi Walid K. , Al-keedi Janan M. , Hassan Susan I. , Abdulhameed Noor R. , Mustafa Muna B.
Published: December 2021

Background: For efficient laser tattoo removal, photodisruption of tissue can ensure a very powerful means to shutter ink granules. At very high laser intensity level, photodisruption dominates and selective photothermolysis will have secondary effect in clearing the tattoo ink. Lower laser fluence is all what to trigger non-linear photons absorption and the generation of exploding cavitation bubbles that can tremendously hammer the ink granules.

Subjects, materials, and methods: Three domestic white rabbits; each received simultaneous injections of a color pigment tattoo under general anesthesia, followed by a single session of (1064) Q.S Nd: YAG nanosecond laser pulses for tattoo removal.

Results and Discussion: Spectroscopic properties of black, dark brown and red tattoo inks were studied. Near threshold laser fluence was selected to select the optimum conditions for obtaining scar-free treatment. Histological images of the biopsies, taken after thirty days of laser treatment of black, dark brown and red tattoos showed a marked reduction in pigment granules size with no appearance of hyperplasia or inflammatory cells. Coexistence of macrophages was suggested to be responsible for actively phagocytizing the laser-dispersed tattoo fragments.

Conclusion: skin biopsies have demonstrated ink granules local redistribution. Photodisruption at 1064nm laser effectively targeted black and dark brown tattoo pigments by the generation of cavitation bubbles. The weaker laser light absorption of red pigments at 1064nm only showed tattoo clearance when using 532nm wavelength.
Evolution of a Polydisperse Ensemble of Ellipsoidal Crystals with Fluctuating Growth Rates in Supercooled Melts
Authors: Nikishina M.A.
Published: December 2021

In this paper, an analytical solution to the model of the evolution of ellipsoidal crystals with fluctuating growth rates at the intermediate step of bulk phase transition is presented. A complete system of integrodifferential equations describing the problem was derived and analytically solved using the Laplace integral method. The kinetics of supercooling removal in melts has been found. The particle-volume distribution function represents a pike-shaped curve decreasing its maximum with time. It is demonstrated the differences in the distribution function for ellipsoidal and spherical crystals.
The Variation Effect of Mg-doped NPs Prepared by Sol-Gel Method on its Structural Properties and Biological Activities
Authors: Ahmed Duha S. , Ali Noor Q. , Taha Ali A.
Published: December 2021

In this paper, we reported the synthesis of NiO NPs and Mg doped-NiO NPs using the facile sol-gel method. Besides, the influence of the variation of Mg dopant on the structural, morphological and optical properties of the prepared Mg-NiO NPs was studied. The synthesized Mg-NiO NPs nanoparticles were characterized by X-Ray Diffraction Analysis (XRD), Energy Dispersive X-ray Spectroscopy (EDS), Fourier-Transform Infrared Spectroscopy (FTIR), Field-Emission Scanning Electron Microscopy (FE-SEM), and UV-Vis spectrophotometer. The X-ray diffraction confirmed the formation of the cubic structure of Mg doped-NiO NPs after doping with the magnesium. The increase in the crystal size was observed with the increase in the concentration of the Mg dopant element. The FESEM images reveal the formation of nickel oxide through the appearance of spherical clusters, while the hybrids appear as wrinkled surface covered with spherical particles of magnesium. The UV-Vis spectrum showed a shift towards shorter wavelengths with an increase in the concentration of the Mg dopant element due to the quantum confinement effect. The hemolysis activity study showed that NiO NPs had a low hemolysis percentage of 1.47% and increased with increasing concentration. While, increasing of the RBC hemolysis (5.9%) after NiO doped with Mg. The antibacterial activity was studied againstS. aureusandP. aeruginosabacteria, and indicated the highest growth inhibition zones of Mg-doped NiO NPs as compared with NiO NPs against ofStaphylococcus aureusandPseudomonas aeruginosa, respectively.
The effect of left ventricle ischemia severity on cardiac performance appeared on ejection fraction using radioactive TC 99m MIBI in comparison with echocardiography
Authors: Mohammed M K , Essa S I
Published: December 2021

Ischemic heart disease is a major causes of heart failure. Heart failure patients have predominantly left ventricular dysfunction (systolic or diastolic dysfunction, or both). Acute heart failure is most commonly caused by reduced myocardial contractility, and increased LV stiffness. We performed echocardiography and gated SPECT with Tc99m MIBI within 263 patients and 166 normal individuals. Left ventricular end systolic volume (LVESV), left ventricular end diastolic volume (LVEDV), and left ventricular ejection fraction (LVEF) were measured. For all degrees of ischemia, there was a significant difference between ejection fraction values measured by SPECT and echocardiography, and there were no significant differences among end systolic volume and end diastolic volume value calculated by two methods for all cases.

The mean value for EDV (ECHO)/EDV (SPECT) was 1.07 ± 0.31 for degree (1, 2); in the degree 3 the mean value was 1.02 ± 0.08, and 1.005 ± 0.07 for degree 4.

The mean value for ESV (ECHO)/ESV (SPECT) was 1.08 ± 0.34 for degree (1, 2); while 1.03 ± 0.12, 1.021 ± 0.128 for degree 3 and 4 respectively.

This study was showed a good relation between left ventricular size and ejection fraction measured by SPECT with Tc99m, and echocardiography.
Study the radioactive concentration for soil samples contaminated with depleted uranium in Al-Nahrawan site at Baghdad governorate using high purity germanium detector
Authors: Essa B. H. , Siyah M.A. , Al-Mashhadani A.H.
Published: December 2021

This study is investigating the radioactivity in soil samples at the Al-Nahrawan site. The radiation survey appears there are 3000 square meters area are contaminated with DU in AL-Nahrawan site identified using Geiger–Müller (GM) for radiation survey and gamma spectrometry for 52 soil samples analysis taken from AL-Nahrawan site at different depths (0-70) cm and different locations. The results of gamma analysis using high-purity germanium show that the ratio between 235U/238U is less than 0.00720 (neutral ratio), and it has different values from 0.002-0.00588, and the average value of radioactive nuclides concentration for (238U, 235U and 40K) are (76019.61, 259.55 and 147.5) Bq/kg respectively, these values are higher than the (BG) radioactive concentration levels in Iraq for (238U and 235U) isotopes, and the analysis of 40K concentration appeared in the acceptable limits. The health effects of depleted uranium in the human body it is exposed to many health troubles through the entry of uranium oxide particles.
Laser induced plasma of cadmium oxide: structural, morphological and optical properties
Authors: Hussein Tamara S. , Ahmed Ala F.
Published: December 2021

In this study, the effect of grafting with Iron (Fe) ratios (0.1, 0.3 and 0.5) on the structural and optical properties of cadmium oxide films (CdO) was studied, as these films were prepared on glass bases using the method of pulse laser deposition (PLD). The crystallization nature of the prepared films was examined by X-ray diffraction technique (XRD), which showed that the synthesis of the prepared films is polycrystalline, and Atomic Force Microscope (AFM) images also showed that the increased vaccination with Iron led to an increase in the crustal size ratio and a decrease in surface roughness, The absorption coefficient was calculated and the optical energy gap for the prepared thin films. It was found the absorption decreases and the energy gap decreases with the increase of doping ratio.
Impact of CNT Concentrations on Structural, Morphological and Optical Properties of ZnO: CNT Nano composite Films
Authors: Abd - Alsada A.S. , Alias M. F. A.
Published: December 2021

In this study, zinc oxide: carbon nanotube (ZnO: CNT) nano composite films with varying CNT concentrations (0,3,5,10, and 15) wt percent were generated utilizing the pulsed laser deposition (PLD) procedure on clean glass substrates at room temperature. The impact of CNT concentration on the structural, morphological, and optical features of ZnO: CNT nano thin films as deposited was examined. X-ray diffraction was used to evaluate the structure of the generated ZnO: CNT thin films, while an atomic force microscope was used to explore the morphological features of the nano films (AFM) and field emission scan electron microscopy (FESEM). The optical properties of prepared thin films were characterized and studied using UV-VIS-NIR spectrophotometer. The structures of prepared ZnO: CNT with different concentration of CNT thin films were polycrystalline. ZnO: CNT nano thin films were synthesized in hexagonal phase and the dominate orientation is (101). The crystallite sizes are 32 and 26 nm for (101) and (100)) planes for ZnO and ZnO: 15% CNT nano films respectively. These crystallite size are decreased with increasing CNT (0, 3,5,10 and 15) wt. %. The lowest grain size can be shown for ZnO, while the largest grain size can be seen in ZnO: CNT nano thin with 15% concentration, whereas FESEM micrographs displayed a typically rough, pronounced microstructure, with surface protrusions. The energy gap (Eg) of ZnO: CNT nano thin film with various concentrations is computed. The result analysis shows that Eg decreased with increasing CNT weight concentration. This type of behaviors make the prepared films are good candidate for broad range of applications such as optoelectronic and display devices.
2.4 GHz Microstrip Patch Antenna for S-Band Wireless Communications
Authors: Abdulhussein Alaa M. , Khidhir Ali H. , Naser Ahmed A.
Published: December 2021

For any wireless communication, the antenna plays a very important role. The request for this technology is reduced antenna size, weight, and cost with a low profile, high performance, and low return loss (RL). To meet these requirements, the microstrip patch antenna (MPA) can be used. This research represents the design and manufacture of the MPA for the 2.4 GHz applications with very low RL and perfect voltage standing wave ratio (VSWR). Computer simulation technology (CST) studio is used to design and simulation. The proposed MPA is fabricated on flame retardant (FR-4) material as a substrate. The results show that the MPA is capable to deal with RL of -38.86 dB at the frequency of 2.393 GHz with a bandwidth (BW) of 58 MHz and VSWR of 1.02. The volume of the antenna is 75.85 × 57.23 × 1.6mm3.
Theoretical investigation of the density and the heat capacity of [EMIM][BF4] and its MWCNTs ionanofluids: Effect of temperature and MWCNTs concentration
Authors: Hasen H.M. , Abdulmajeed B. A.
Published: December 2021

The density and specific heat capacity is an important parameter for heat transfer fluids (HTFs) specially which used for cooling or heating purposes. In this study the density of ethyle methyl imidazolium tetrafluoro borate ionicliquids ([EMIM][BF4]) measured experimentally. In addition, the density (ρ) and the specific heat capacity (Cp) of the ionanofluid (INF) were calculated theoretically. The studied INF composed of multi-walled carbon nanotubes (MWCNTs) dispersed in the ionicliquid (IL) [EMIM][BF4] in the concentrations (0.5%, 1%, 3%, 5%, 7% and 9%). Scanning electron microscopy and differential scanning calorimetry measured for the used MWCNTs. The density and the specific heat capacity of pure [EMIM][BF4] and its INFs were plotted versus temperature in a graphs. The results show that the density of [EMIM][BF4] and its INFs decreased linearly with temperature. The density increased by 0.243%-3.968% for 0.5%-9% MWCNTs concentration in INFs, reaching maximum value of 1.329 g.cm-3 at 20 °C. In contrast the specific heat capacity of [EMIM][BF4] and its INFs increased linearly with temperature with an enhancement of about 0.417%-7.99% for 0.5%-9% concentration of MWCNTs reaching maximum value of 1.812 J/g.K at 358.15K with 9%MWCNT concentration. That’s mean the addition of MWCNT cause increasing both of the density and the specific heat capacity of INF.
Synthesis of Polyaniline–Cerium Oxide Nanocomposite for Photodetector Application
Authors: Hassen Maryam M. , MJbrahim Isam
Published: December 2021

In this paper nanocomposites materials of Polyaniline (PAni) nano-fiber (NFs) and Cerium oxide (CeO2) nanoparticles (NPs) were prepared by two method; hydrothermal and chemical method respectively. The spin coating method was used to prepare PAni and Pani/CeO2on Si and glass substrates and then screened with XRD, FE-SEM, UV-Vis and as-prepared thin-film photodetectors. The X-ray diffraction pattern of all the prepared films showed the presence of crystalline nature. It was found that the PAni/CeO2films have a cubic crystal structure.. FESEM results proved that the PAni film prepared have nanofiber like structure, while the PAni/CeO2films proved that CeO2NPs fully caped with PAni nanofiber. The UV-Vis spectra showed peaks of PAni 340nm, 651nm and PAni/CeO2320nm, 620 nm and in the energy gap it is noticed that the band gap value decreases as the CeO2 ratios increases where the maximum values of energy gap of B-band and Q-band (1.65 – 2.74) eV. The maximum sensitivity values of the photoconductive detectors were observed at PAni/CeO2(2 vol.%) nanoparticles deposited on n-Si substrate which were approximately (2696.5%, 946.15%, 1402.2%, 1613.9%3837.9%, and 2700%) for wavelengths 360, 465, 510, 595,660 and 965 nm respectively.
Optical Emission Spectroscopic Analysis of Plasma Parameters in Cadmium by Nd: YAG laser Technique
Authors: Tawfeeq Uday H. , Abbas Ahmed K. , Aadim Kadhim A.
Published: December 2021

In this work, optical emission spectroscopy (OES) was used to estimate the parameters of plasma electron temperature (Te), electron density (ne), plasma frequency (fp), Debye length (λD), and Debye number (ND). Understanding how an energy pulsed laser affects these variables is also important. Irradiation of pure cadmium using an Nd: YAG laser pulse with a wavelength(1064)nm and energy ranging from (200-600)millijoules, of frequency (6) Hz. The spectrum of laser-induced plasma was detected under atmospheric pressure. It was discovered that when the energy of the laser pulse rises, the intensity of the CdI and CdII lines increases.
Concentration of heavy metals in the drinking water of Kut city - Iraq and their impact on health
Authors: Al-Yasiri Mohammad Yahya R , Al-Attabi Hadi Dwaich Z.
Published: December 2021

The quality of drinking water is related to the state of the water supply networks, pollution, and contamination of drinking water with contaminants of both anthropogenic and natural origin. Water samples were collected from 22 different waterworks in Kut, Iraq, and heavy metal concentrations (Pb, Ni, and Zn) were analyzed. In various parts of the city, 22 sampling sites were pre-defined. The results indicated that heavy metal concentrations in water samples did not surpass WHO guidelines (World Health Organization).
The Effect of Working Gases Mixing Ratios on the Synthesis and Characteristics of TiO2/SiO2 Nanocomposite via Closed-Field unbalanced DC Magnetron Co-Sputtering Technique
Authors: Mutesher N. H.
Published: December 2021

The objective of this research is to study the influence of deposition parameters such as gases mixing ratio O2/Ar on the structural and optical properties of the TiO2/SiO2 nanocomposite films synthesized using closed field unbalanced dc magnetron co-sputtering technique. The nanocomposite thin films were characterized using x-ray diffraction (XRD) to determine the phase structure, and Fourier transform infrared (FTIR) spectroscopy to investigate Si-O-Si, Ti-O and Si–O–Ti. functional groups. The UV-VIS. absorption spectra of the synthesized films reveal that the indirect energy band gap was found to be 2.75 eV. The mixing ratio of Oxygen and Argon (O2/Ar) gases has a pronounced controlling effect on the structural and optical properties of such nanocomposite.
Radon concentration measurement in water reservoirs for some areas of north Baghdad by RAD7
Authors: Khalaf Salah Q. , Hussien Hayder S.
Published: December 2021

Radon is a naturally occurring, odorless, colorless, radioactive, tasteless, and noble gas. Radon concentrations have been measured by the usage of alpha spectroscopy (RAD-7). The RAD-7 measuring process is based on detecting alpha particles produced from the disintegration of radon and its products using a solid-state alpha detector (usually silicon), and then converting alpha radiation directly to an electrical signal. The radioactivity of radon gas was measured in forty-two samples from reservoir water for different areas north of Baghdad utilizing a RAD7 detector. This study proved that the high value of radon concentrations was less than the permissible limit as recorded by the World Health Organization.
Effect of Adding Nanoparticles Ag2O on Mechanical Properties and Thermal Conductivity of PMMA/ Polypropylene Fiber Composites
Authors: Yassien Hussien. A. , Jubier Najwa J.
Published: December 2021

In this research, mechanical properties (hardness, impact strength, comparison strength) and thermal conductivity are examined for PMMA/polypropylene fiber composites reinforced with a different weight fraction of Ag2O nanoparticles (0%,0.05%,0.1%,0.15%,0.2%,0.25 and 0.3%). Samples prepared by Hand Lay-Up Moulding method at room temperature according to the international standard dimensions for each test, results showed a noticeable improvement in the values of mechanical properties and thermal conductivity with increasing the weight fraction of the silver oxide nanoparticles.
Structure, Morphology and Optical Properties of SnO2Nanoparticle Synthesized via Ultrasonic Spray Pyrolysis Technique: Effect of CuO Doping Concentration
Authors: Abdullah H.D. , Al-Taay H.F. , Khalaf M. K. , Oleiwi H. F. , Rahma A. J.
Published: December 2021

Tin oxide (SnO2) and doped with various concentrations of copper oxide (CuO) of (3, 5, and 7%) nanoparticles were synthesized via a simple, cost-effective, and nontoxic ultrasonic spray pyrolysis technique on glass substrates. Crystalline structure, surface morphology of the SnO2pure and SnO2:CuO, films have been studied by Field Emission Scanning Electron Microscopy (FESEM), Atomic Force Microscope (AEM) and X-Ray Diffraction (XRD). The effect of CuO doping on the electrical properties of SnO2films was investigated using Hall effect measurments. The optical properties of the prepared films have been characterized by Ultraviolet-visible spectrophotometer. High distribution densily and good growth SnO2and SnO2: CuO nanoparticles on the substrate with an average particles size ranged from 30 to 110 nm. The crystalling and grain size were changed according to the CuO doping ratio. There is a redshift within the UV-Vis spectra was observed with an increasing CuO ratio of (3, 5 and 7%)
Simulation and Numerical Modelling of CIGSSe-Based Solar Cells by AFORS-HET
Authors: Aswad Ammar J. , Hassan Nadeem K. , Ahmed Adnan R.
Published: December 2021

A general equation to determine properties of penternary solar cell based on Cu (In, Ga) (Se, S) 2 (CIGSSe) with a double buffer layer ZnS/Zn0.8Mg0.2O(ZMO) were derived. Numerical analysis of a (CIGSSe) solar cell with a double buffer layer ZnS/ZMO, CdS free absorber layer, were investigated using the AFORS-HET software simulation. Taking into consideration the effect of thickness and doping concentration for the CIGSSe absorption layer, ZnS buffer layer and ZnO:B(BZO) window layer on the electron transport, short circuit current density (Jsc) and open circuit voltage (Voc); numerical simulation demonstrated that the changes in band structure characteristics occurred. The solar energy conversion efficiency is 28.34%, the filling factor is 85.59%, the open circuit voltage is 782.3 mV, the short circuit current is 42.32 mA. then we take the range of the gradient between the ratio of x and y for the absorption layer, and the best result of Voc, Jsc, FF, Eff equal (838.7 mV, 40.94 mA/cm2, 86.23%, 29.61%) respectively at x= 0, y= 0.26.
Hydrophilic properties of nano-structure silicate synthesis by sol-gel-dipping technique
Authors: Ali Falah H
Published: December 2021

Nano-structure SiO2 was prepared in this work by use Sol-Gel method. Then, studying optical and structural properties of SiO2, the absorption spectrum was determined in UV region, while nano-structure and morphology was investigated by XRD and AFM respectively. The particle size measured by use AFM Analysis which about (55.12 nm).super hydrophilic was gotten after 1 hour of UV irradiation for the prepared SiO2 thin-film.
Fabrication of Wear Resistance Ni/SiC nano composite Coating by Electro co-deposition
Authors: Salam N , Jaleel M A.
Published: December 2021

In this paper, we succeeded in obtaining a Ni/SiC nano composite coating using conventional electro deposition by adding different amount of SiC nanoparticles to a nickel-watt bath to be co-deposited. The effect of electro deposition conditions was studied by changing the amount of SiC nanoparticles in the nano composite, and the deposition current density which affects on the participation of SiC nanoparticles in the coating. The morphology and mechanical properties of the electrodeposited nano-composite were studied. The wear behavior of the nano-composite coatings was evaluated on a ball-on-disk test. It was found that the increased micro hardness and wear resistance of the nano-composite coatings increased with increasing content of the SiC nano-particulate in bath.
Studying the effect of diesel Power Generator noise on the publicity in Ramadi city
Authors: Farhan Ahmed Obeed , Salman Raid Khider , Farhan S.S.
Published: December 2021

The current study including investigating the effect of noise pollution produced by the diesel power generators on the public health, in one of Al-Ramadi districts. The measurements were taken using decibel meters within different distances and directions from the power station. The study showed that the noise levels are too high for the residential buildings, especially for the regions in which buildings are stacked together or distributed in a way that the sound wave is improved through the eco caused by this distribution.
Biosynthesis and Characterization of ZnO: Ag2O Nanocomposite for Antifungal Efficacy
Authors: Fayyadh Ali Abdullah , Jaduaa Alzubaidy Muneer H.
Published: December 2021

In this study, biosynthesis zinc and silver oxide nanocomposite (Bs-ZANc) were prepared using an eco-friendly biological synthesis method using silver nitrate, zinc nitrate hexahydrate, and Lawsonia inermis (Henna) plant extract with four different concentrations; (0.1, 0.2, 0.3, and 0.4) molar. The detailed characterization of Bs-ZANc was performed using Grazing X-ray diffraction technique (G-XRD), Field Emission Scanning Electron Microscope (FE-SEM), X-ray energy dispersive spectroscopy (EDX), Zeta Potential (Z.P.), and Dynamic Light Scattering (DLS). In addition to studying the spectroscopic properties using Fourier transform infrared spectroscopy (FTIR). The result showed good inhibitory efficiency of Bs-ZANc against some types of fungal such as; Penicillium spp., Aspergillus spp., and Candida Albicans. Further, a comparison was made between Bs-ZANc and Lawsonia inermis (Henna) plant extract only regarding antfungal efficacy.
Green synthesis of iron oxide nanoparticles (Fe2O3) using saffron extract
Authors: AL-Husseini A H , Sih B T , Al-Araji A M
Published: December 2021

In this study, iron oxide nanoparticles were prepared using saffron plant extract, and the prepared particles were diagnosed using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray resolution (EDX), infrared spectroscopy (FTIR) and ultraviolet-visible spectroscopy (UV–Vis). This method falls within the green chemistry, an environmentally friendly method and at a lower cost than other methods
Synthesis and characterization of nickel nanoparticles formed by solution cold plasma jet
Authors: Abdulhadi Omar O. , Rahmman Ibrahim A. AA. , Obaid A. S.
Published: December 2021

In this work, nickel nanoparticles were prepared from nickel chloride solution using the liquid phase plasma reduction technique. A cold plasma jet was used for this purpose. The variation of the concentrations 0.5mM, 1mM and 2 mM and was used to study optimal condition of nickel nanoparticles formation. A concentration of 1 ml was observed to be the best, by using UV-Vis spectroscopy and Field emission scanning electron microscopy (FESEM). The optimum concentration was used to formation nanoparticles solution with variation the exposure time of cold plasma jet at (5 min, 10 min, 15 min ) respectively. The results shown by UV-Vis spectroscopy the nanoparticle peaks produced by surface plasmon absorption were observed around 365-375 nm according the discharge time of cold plasma. The nanoparticles were spherical homogenous as observed by Field emission scanning electron microscopy (FESEM) which also shown the average particle size about 25nm, and by dynamic light scattering (DLS) and also zeta potential (ZP) measurements were observed non-aggregated in the long term, the particles are very stable colloid, also no visible aggregation have been seen on the prepared samples in this concentration (1mM). In contrast to other concentrations which showed a nonhomogeneous morphology and aggregated. X-ray Diffraction (XRD) showed that NiNPs have a face-centered cubic (FCC) structure with a crystalline size of around 12.5 nm, and also Inductively Coupled Plasma mass Spectrometry (ICP-mass) were used to characterize the prepared samples.
Evaluation of Paromomycin Loaded Chitosan Nanoparticles and Oxidative Stress Activities against Entamoeba Histolytica
Authors: Hamad Hanaa Kamil
Published: December 2021

This investigation was carried out to estimate the antiparasitic potential of chitosan nanoparticles loaded with paromomycin against Entamoeba histolytica infected. After rats inoculated orally in a dose 103 viable cysts for acute infection; then treated with paromomycin, chitosan nanoparticles as a single or combined therapy given for seven days. Stool examination revealed a significant decrease in the number of Entamoeba histolytica cysts in all treated infected rats compared with infected non-treated. Combined treatment provided better results than single treatment. The best effect was observed in the group of rats treated with chitosan nanoparticles loaded with paromomycin. Also, the oxidative stress markers Glutathione (GSH) and Lipid Peroxide (Malondialdehyde) (MDA) were assessed in liver tissue homogenate. The current work is the first time of using chitosan nanoparticles loaded with paromomycin as therapeutic agents against experimental amoebiasis. It was shown that the highest degree of effectiveness attained by the synergistic action of paromomycin and chitosan nanoparticles as was indicated by lower parasite count and GSH, MDA concentration.
Green Synthesis and Characterization of Gold Nanoparticles from Malus viridisand Capsicum annuum as AnticancerAgent
Authors: Abdulwahed Sh.H. , Alias M. F. A. , MohammedHasan Z. Y.
Published: December 2021

Gold nanoparticles (AuNPs) were synthesied by eco friendly method (green method) through the reduction of aqueous chloroauric acid (HAuCl4.4H2O) solution using apple and pepper (Malusviridis and capsicum annuum) peels extract as a reducing and stabilizing agent. AuNPs were characterized using various instrumental techniques including energy dispersive spectroscopy (EDS), Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), Atomic force microscope (AFM), field emission scanning electron microscopy (FESEM) ultraviolet-visible spectroscopy (UV-Vis), and Zeta-Potential. The synthesized AuNPs was used against breast cancer cell line MCF-7 to compare their biological effect as anticancer agent. Results showed that the AuNPs formed with both plants had a physical charastaristics differ from each other, even in their effects on cancerous cells, where the inhibition rate of AuNPs synthesized using apple (Malusviridis) peel extrac has larger values than Capsicum annuum. The AuNPs formed from synthesized using both plants showed an acceptable stability.
Study the surface morphology and the chemical composition of NiPc:NiO nanocomposite thin films
Authors: Qassim A A , Sadeq A N
Published: December 2021

The synthesis of organic and inorganic thin films based on nickel phthalocyanine (NiPc) and nickel oxide NiO nanoparticles. the thin films prepared by spin coating technic. The volume of the solution dropped on each slide is 50 micro liter at room temperature. Nanocomposites thin films NiPc:NiO with different percentage 1:0 75:25, 50:50, 25:75 and 0:1 are analysed using FESEM and EDX. The study of morphology and chemical composition of the synthesized thin films revealed the formation of NiPc in the form of rods and nickel oxide similar to spherical clusters. The EDX spectra revealed the appearance of oxygen in a high percentage in some samples, perhaps as a result of the chemical and physical adsorption. This is the first study on the combination and description of NiPc:NiO nanocomposite.
Thermochromic and opacity behaviors in vanadium dioxide nanofilms: a theoretical study
Authors: Shallal Ikhlas H , Abdul-Ameer Nidhal M , Abdul-Hasan Shaymaa Q , Abdulrida Moafak C
Published: December 2021

Vanadium dioxide nanofilms are one of the most essential materials in electronic applications like smart windows. Therefore, studying and understanding the optical properties of such films is crucial to modify the parameters that control these properties. To this end, this work focuses on investigating the opacity as a function of the energy directed at the nanofilms with different thicknesses (1–100) nm. Effective mediator theories (EMTs), which are considered as the application of Bruggeman’s formalism and the Looyenga mixing rule, have been used to estimate the dielectric constant of VO2 nanofilms. The results show different opacity behaviors at different wavelength ranges (ultraviolet, visible, and infrared). The results depict that the highest opacity of the insulating phase is achieved at the ultraviolet region and it reduces for the metal phase. Besides, the results demonstrate that the opacity possesses a redshift during the changes at the three phases. Regarding the infrared region, the lowest opacity value is achieved at the insulator phase and it increases to the highest value at the metal phase. In the visible region, the opacity behavior remains similar in the three phases. It is worth noting that the lowest opacity is found for thinner nanofilm. Since both the refractive index and the extinction index are among the most essential optical constants, hence, both of them were compared with the experiment results, and an excellent agreement is achieved between them.
Novel use of a sequential standardized oral board exam to assess PGY1 resident progression
Authors: O’Mara Keliana , Holder Martina , Lagasse Carrie , Lemon Stephen J
Published: December 2021

Purpose

A standardized oral board exam was created to longitudinally assess postgraduate year 1 (PGY1) pharmacy residents in key domains.

We provide a descriptive review of a novel oral board exam administered quarterly to our PGY1 pharmacy residents. Preceptors from our core rotations (internal medicine/infectious diseases, adult critical care, oncology, pediatrics, and administration/health policy and outcomes) developed questions based on situations commonly encountered by PGY1 residents to assess residents’ communication; the content of their response, assessment, and plan; and coachability. Over the 4-year history of this assessment, scoring has matured to consider whether a resident has or has not met or has exceeded expectations for a PGY1 resident at a given stage in their training. Our comprehensive feedback and action planning approach included residents’ self-assessment, feedback from the exam committee, development and implementation of a customized training plan for execution, and dissemination to our preceptors. Systematically assessing our PGY1 residents with this innovative method provided a process for tracking their performance and served as a baseline for those who completed additional training at our institution.

Conclusion

A standardized quarterly oral board exam was developed to identify residents’ strengths and areas for improvement at established periods during the PGY1 residency training program. This standardized assessment, paired with individualized action plans and open communication with key stakeholders, stimulated development in residents’ performance, communication, and interpersonal skills. We aim to expand this system’s application to identify predictors of success for candidates we interview for our postgraduate training programs.