bluuebunny/crossref_metadata_2025 huggingface dataset:
Dielectric constant of thin film graphitic carbon nitride (g-C3N4) and double dielectric Al2O3/g-C3N4
Authors: Patra Purna Chandra , Mohapatra Y. N.
Published: March 2021

Graphitic carbon nitride (g-C3N4), a highly stable wide bandgap material, is yet to be evaluated for thin-film applications in devices since its basic electrical properties are not understood. We study its vacuum-deposited thin film form, and in combination with Al2O3, in sandwiched devices using capacitance–voltage (C-V) and current–voltage (I-V) characteristics over a wide range of temperatures and frequencies. The dielectric constant of g-C3N4 alone is between 7 and 8 for frequencies 100 Hz to 100 kHz, but it is almost double at 14–16 when used in conjunction with a thin layer of Al2O3. The increased dielectric constant is attributed to additional polarization at the interface of the two dielectrics. The leakage current density is of the order of 10–7 A/cm2 and shows slight asymmetry. The mechanisms of current transport are mainly space charge limited at fields higher than 5 × 105 V/cm. We attribute the small but significant difference between forward and reverse bias to the presence of the negative sheet charge at the interface between the two dielectrics. The interfacial charge density is estimated to be 1011 cm−2.
Antibiotic prescribing patterns of general practice registrars for infective conjunctivitis: a cross-sectional analysis
Authors: Cherry Marcus D. , Tapley Amanda , Quain Debbie , Holliday Elizabeth G. , Ball Jean , Davey Andrew , van Driel Mieke L. , Fielding Alison , Spike Neil , FitzGerald Kristen , Magin Parker
Published: March 2021

ABSTRACT INTRODUCTION Over-prescription of antibiotics for common infective conditions is an important health issue. Infective conjunctivitis represents one of the most common eye-related complaints in general practice. Despite its self-limiting nature, there is evidence of frequent general practitioner (GP) antibiotic prescribing for this condition, which is inconsistent with evidence-based guidelines. AIM To investigate the prevalence and associations of GP registrars’ (trainees’) prescription of antibiotics for infective conjunctivitis. METHODS We performed a cross-sectional analysis of the Registrar Encounters in Clinical Training (ReCEnT) ongoing prospective cohort study, which documents GP registrars’ clinical consultations (involving collection of information from 60 consecutive consultations, at three points during registrar training). The outcome of the analyses was antibiotic prescription for a new diagnosis of conjunctivitis. Patient, registrar, practice and consultation variables were included in uni- and multivariable logistic regression analyses to test associations of these prescriptions. RESULTS In total, 2333 registrars participated in 18 data collection rounds from 2010 to 2018. There were 1580 new cases of infective conjunctivitis (0.31% of all problems). Antibiotics (mainly topical) were prescribed in 1170 (74%) of these cases. Variables associated with antibiotic prescription included patients’ Aboriginal or Torres Strait Islander status, registrar organisation of a follow up (both registrar and other GP follow up), and earlier registrar training term (more junior status). DISCUSSION GP registrars, like established GPs, prescribe antibiotics for conjunctivitis in excess of guideline recommendations, but prescribing rates are lower in later training. These prescribing patterns have educational, social and economic consequences. Further educational strategies may enhance attenuation of registrars’ prescribing during training.
Revealing lineage-related signals in single-cell gene expression using random matrix theory
Authors: Nitzan Mor , Brenner Michael P.
Published: March 2021

Significance

Single-cell technologies are rapidly advancing, allowing us to gauge the heterogeneity and structure of cellular communities, tissues, and full organisms. The correlations between genes and between cells within such systems can reveal patterns of regulatory interactions, physical structure, and temporal progression of cells along biological processes. However, it is generally a challenge to identify and tease apart these mixed signals within the noisy, high-dimensional single-cell data. Here, we show it is possible to detect a signature for lineage in the covariance spectrum of single-cell data, predict how it will change with developmental time, and predict how it can be extended to examine the spatial structure of a tissue.
The evolution of altruism through war is highly sensitive to population structure and to civilian and fighter mortality
Authors: Dyble Mark
Published: March 2021

Significance

Many evolutionary theorists have suggested that the human capacity for altruism was forged in war, with cohesive and altruistic groups outcompeting their selfish neighbors. Assessing this “parochial altruism” hypothesis relies largely on computational modeling. Here, I reexamine a well-known model that explores the coevolution of altruism and war. As well as clarifying the importance of factors such as the lethality of war to fighters and civilians, the results show that the evolution of altruism in this model relies on a degree of genetic differentiation between groups that exceeds that seen among hunter-gatherers. Furthermore, when the model produces a more realistic population structure, altruism does not evolve, casting doubt on the plausibility of the parochial altruism hypothesis.
Behavioral responses across a mosaic of ecosystem states restructure a sea otter–urchin trophic cascade
Authors: Smith Joshua G. , Tomoleoni Joseph , Staedler Michelle , Lyon Sophia , Fujii Jessica , Tinker M. Tim
Published: March 2021

Significance

Ecological processes that enhance or dampen the likelihood of shifts between top-down (i.e., predator-driven) and bottom-up (i.e., resource-driven) forcing underpin community regulation, functioning, and stability. Here, we demonstrate how the behavioral response of an apex predator to changes in prey behavior and condition (i.e., energetic profitability) can dramatically alter the strength of top-down forcing and enhance the role (or relative contribution) of bottom-up community regulation, depending on the spatial organization of diverse ecosystem states. These results highlight the role of consumer and predator trait-mediated responses to resource mosaics that are common throughout the natural world and enhance understanding of reciprocal feedbacks between top-down and bottom-up forcing on the regional stability of ecosystems.
A conserved Ctp1/CtIP C-terminal peptide stimulates Mre11 endonuclease activity
Authors: Zdravković Aleksandar , Daley James M. , Dutta Arijit , Niwa Tatsuya , Murayama Yasuto , Kanamaru Shuji , Ito Kentaro , Maki Takahisa , Argunhan Bilge , Takahashi Masayuki , Tsubouchi Hideo , Sung Patrick , Iwasaki Hiroshi
Published: March 2021

Significance

A DNA double-strand break (DSB) can be repaired accurately by homologous recombination. The Mre11-Rad50-Nbs1 (MRN) complex is responsible for initiating homologous recombination by degrading 5′-ended DNA strand, where its activation by the Ctp1 cofactor plays a pivotal role. Here, by using purified fission yeast proteins, we show that two major elements comprise MRN activation. First, phosphorylation of Ctp1 promotes the physical interaction between MRN and Ctp1. Second, the C terminus of Ctp1 activates nucleolytic processing of DSB ends. In the latter case, a small peptide comprising only 15 amino acids from the Ctp1 C terminus is sufficient to activate MRN. Our results elucidate the core elements underlying MRN activation by Ctp1.
Expansions of adaptive-like NK cells with a tissue-resident phenotype in human lung and blood
Authors: Brownlie Demi , Scharenberg Marlena , Mold Jeff E. , Hård Joanna , Kekäläinen Eliisa , Buggert Marcus , Nguyen Son , Wilson Jennifer N. , Al-Ameri Mamdoh , Ljunggren Hans-Gustaf , Marquardt Nicole , Michaëlsson Jakob
Published: March 2021

Significance

Respiratory diseases are leading causes of death worldwide. However, the local immune cell composition in the human lung and individual outliers within the population still remain largely undescribed. We here identify adaptive-like NK cell expansions with tissue-resident traits in lung and blood in approximately 20% of individuals. This particular NK cell subset, which differed from adaptive-like CD16
+
blood NK cells, was hyperresponsive to target cell stimulation. Individuals with such in vivo-primed, expanded NK cells will likely experience a different course of acute lung disease such as viral infections. Furthermore, we believe that target cell-hyperresponsive tissue-resident NK cells represent a future tool in the treatment of lung cancer.
The pentapeptide-repeat protein, MfpA, interacts with mycobacterial DNA gyrase as a DNA T-segment mimic
Authors: Feng Lipeng , Mundy Julia E. A. , Stevenson Clare E. M. , Mitchenall Lesley A. , Lawson David M. , Mi Kaixia , Maxwell Anthony
Published: March 2021

Significance

Pentapeptide-repeat proteins, such as MfpA and Qnr proteins, have an intriguing right-handed quadrilateral β-helical fold that gives rise to an elongated roughly cylindrical structure that resembles the shape of a double-stranded DNA helix. It has been speculated that these proteins, particularly those that interact with bacterial DNA gyrase, act as DNA mimics, competing with DNA to fulfil their functions. Until now there has been no direct evidence for this. Using enzymology and X-ray crystallography, we show the mycobacterial MfpA appears to act as a mimic of the transported (T) DNA segment during the gyrase supercoiling cycle, protecting the enzyme from fluoroquinolone antibiotics. These data suggest a mechanism to limit fluoroquinolone efficacy.
Enhanced cytarabine-induced killing in OGG1-deficient acute myeloid leukemia cells
Authors: Owen Nichole , Minko Irina G. , Moellmer Samantha A. , Cammann Sydney K. , Lloyd R. Stephen , McCullough Amanda K.
Published: March 2021

Significance

Acute myeloid leukemia (AML) patients whose cancers are classified as either the RUNX1-RUNX1T1 fusion subtype or the CBFB-MYH11 fusion subtype share the common characteristic of significantly decreased levels of mRNA transcripts encoding the DNA repair enzyme
OGG1
. While these two subtypes consistently correlate with the best prognosis for improved relapse-free and overall survival, the molecular basis for relating enhanced survival to low OGG1 has not been established. To identify the basis for this subtype-specific therapeutic efficacy, we demonstrate the mechanism through which the unique combination of the diminution in OGG1 activity and cytarabine treatment confers preferential cell killing, thereby identifying OGG1 as a novel therapeutic target for AML patients with normal or increased levels of OGG1.
Therapy for Argentine hemorrhagic fever in nonhuman primates with a humanized monoclonal antibody
Authors: Zeitlin Larry , Cross Robert W. , Geisbert Joan B. , Borisevich Viktoriya , Agans Krystle N. , Prasad Abhishek N. , Enterlein Sven , Aman M. Javad , Bornholdt Zachary A. , Brennan Miles B. , Campbell Lioudmila , Kim Do , Mlakar Neil , Moyer Crystal L. , Pauly Michael H. , Shestowsky William , Whaley Kevin J. , Fenton Karla A. , Geisbert Thomas W.
Published: March 2021

Significance

Despite the relatively high disease burden of arenaviruses in South America and Africa, there are currently no Food and Drug Administration-approved drugs for use in preventing or treating any arenavirus infection. Currently, the sole clinically validated treatment option for Argentine hemorrhagic fever (AHF), caused by Junin virus (JUNV), is administration of immune plasma. While the relative success associated with this treatment supports passive immunotherapy interventions, the recent expansion of mAbs used in a clinical setting for infectious diseases offer a highly specific, consistently potent, and generally safe alternative to immune plasma. Here we show that a humanized mAb is highly efficacious in guinea pig and nonhuman primate models of AHF.
Structure of
Arabidopsis
CESA3 catalytic domain with its substrate UDP-glucose provides insight into the mechanism of cellulose synthesis
Authors: Qiao Zhu , Lampugnani Edwin R. , Yan Xin-Fu , Khan Ghazanfar Abbas , Saw Wuan Geok , Hannah Patrick , Qian Feng , Calabria Jacob , Miao Yansong , Grüber Gerhard , Persson Staffan , Gao Yong-Gui
Published: March 2021

Significance

Cellulose is the most abundant biopolymer on Earth and has many potential industrial applications, such as renewable energy and sustainable materials. Here we report the apo and UDP-glucose (UDP-Glc)–bound crystal structures of the catalytic domain of
Arabidopsis thaliana
CESA3. Our results offer a structural basis for how the substrate UDP-Glc and a metal ion, Mn
2+
, which is required for cellulose synthesis, are coordinated in plant CESAs. Furthermore, our structure reveals that CESAs may form homodimers through interactions between specific beta strands that likely aid in the early stages of CESA complex formation.
Life expectancy in adulthood is falling for those without a BA degree, but as educational gaps have widened, racial gaps have narrowed
Authors: Case Anne , Deaton Angus
Published: March 2021

Significance

Without a 4-y college diploma, it is increasingly difficult to build a meaningful and successful life in the United States. We explore what the BA divide has done to longevity, focusing on a measure of expected years lived between ages 25 and 75. In the richest large country in the world, with frontier medical technology, expected years lived between 25 and 75 declined for most of a decade for men and women without a 4-y degree, even prior to the arrival of COVID-19. For those with and without a BA, racial divides narrowed by 70% between 1990 and 2018, while educational divides more than doubled for both Black and White people.
ALS2 regulates endosomal trafficking, postsynaptic development, and neuronal survival
Authors: Kim Joohyung , Kim Sungdae , Nahm Minyeop , Li Tsai-Ning , Lin Hsin-Chieh , Kim Yeongjin David , Lee Jihye , Yao Chi-Kuang , Lee Seungbok
Published: March 2021

Mutations in the human ALS2 gene cause recessive juvenile-onset amyotrophic lateral sclerosis and related motor neuron diseases. Although the ALS2 protein has been identified as a guanine-nucleotide exchange factor for the small GTPase Rab5, its physiological roles remain largely unknown. Here, we demonstrate that the Drosophila homologue of ALS2 (dALS2) promotes postsynaptic development by activating the Frizzled nuclear import (FNI) pathway. dALS2 loss causes structural defects in the postsynaptic subsynaptic reticulum (SSR), recapitulating the phenotypes observed in FNI pathway mutants. Consistently, these developmental phenotypes are rescued by postsynaptic expression of the signaling-competent C-terminal fragment of Drosophila Frizzled-2 (dFz2). We further demonstrate that dALS2 directs early to late endosome trafficking and that the dFz2 C terminus is cleaved in late endosomes. Finally, dALS2 loss causes age-dependent progressive defects resembling ALS, including locomotor impairment and brain neurodegeneration, independently of the FNI pathway. These findings establish novel regulatory roles for dALS2 in endosomal trafficking, synaptic development, and neuronal survival.
Organization of cooperation in fractal structures
Authors: Peng Dan , Li Ming
Published: March 2021

It is known that the small-world structure constitutes sufficient conditions to sustain cooperation and thus enhances cooperation. On the contrary, the network with a very long average distance is usually thought of as suppressing the emergence of the cooperation. In this paper we show that the fractal structure, of which the average distance is very long, does not always play a negative role in the organization of cooperation. Compared to regular networks, the fractal structure might even facilitate the emergence of cooperation. This mainly depends on the existence of locally compact clusters. The sparse inter-connection between these clusters constructs an asymmetric barrier that the defection strategy is almost impossible to cross, but the cooperation strategy has a not too small chance. More generally, the network need not to be a standard fractal, as long as such structures exist. In turn, when this typical structure is absent, the fractal structure will also suppress the emergence of the cooperation, such as the fractal configuration obtained by diluting a random tree-like network. Our findings also clarify some contradictions in the previous studies, and suggest that both removing and inserting links from/into a regular network can enhance cooperation.
The determinant of slip plane and volume potential of landslide mass using resistivity data in Air Kuning Batu Merah, Ambon City
Authors: Souisa M , Sapulete S M , Isnawati
Published: March 2021

To reduce the risk of landslides and to be aware of areas that have the potential for further landslides, detailed measurements of these zones are required. Measurements were made to identify a sliding plane below the surface using the geoelectric resistivity method of the Wenner-Schlumberger configuration. The resistivity data from the interpretation results are used to determine slip plane’s slope and the potential for landslide masses. The research location is on steep hills in Air Kuning Batu Merah, Ambon City. The results showed that the slope angles for line-1 were 4.20 degrees, line-2 was 17.60 degrees, line-3 ranged from (22.80 - 23.20) degrees, and line-4 was 21.80 degrees. Furthermore, the estimated volume potential of landslide mass based on the cross-section of subsurface resistivity is 3,063.88 m3. With an indication of a landslide field, the slope has the potential for a subsequent landslide if affected by external and internal factors.
Design of PM2.5 and PM10 measuring instruments for analysis of air pollution distribution patterns in the dramaga area based on internet of things
Authors: Satria H , Soekirno S
Published: March 2021

Particulate Matter (PM) is the main material commonly used to show the degree of air pollution. PM material has an impact on human health and the visibility of the atmosphere. Standard gravimetric measurements and current commercial instruments for field measurements are still expensive and limited at several points in Indonesia. In this research, a low cost PM2.5 and PM10 measuring instrument was designed, with the application of the Internet of Things (IoT) to support real-time monitoring. This instrument can be used to increase the spatial and temporal resolution of PM data. The system uses the ZH03A which has a correlation of 0.8936 in PM2.5 and 0.8873 in PM10 through comparison with standard instrument. Sensor data is processed by a data logger which is connected to the internet via the ESP8266 module. This module has sent data to the database with 0% data loss on testing and sent to display the actual PM2.5 and PM10 values in a website. The results showed a negative correlation on temperature and positive correlation on humidity. The measurement system has recorded the distribution patterns of PM coming from the northwest of Dramaga.
Study of seawater intrusion in coastal aquifer using total dissolved solid, conductivity and salinity measurement in Labuhan Kertasari Village, West Sumbawa
Authors: Hilmi A , Ulfa A M , Wijaya A , Hadimi L I
Published: March 2021

Indonesia is an archipelagic country that has a larger ocean area than land, many people live in coastal areas and still experience difficulties in obtaining springs that can be used for their daily needs. This study was conducted to see the extent of seawater intrusion into a coastal aquifer in Labuhan Kertasari Village. The method of measuring Total Dissolved Solids, Conductivity, and Salinity is used in studying seawater intrusion into a coastal aquifer. Coastal aquifer samples were taken from open wells and boreholes belonging to residents which are actively used on a daily basis. Analysis of the relationship between TDS, conductivity and, salinity used simple linearity analysis, and distribution mapping using surfer 8. The highest TDS concentration, conductivity, and salinity were 5770 ppm; 8700 MS/cm; and 4600 ppm on the S8. While the TDS concentration, conductivity, and salinity were the lowest consecutively were 836 ppm; 1258 MS/cm; 700 ppm on S26. In general, the coastal aquifer in residents’ wells has experienced various intrusions and has decreased at a distance from the shoreline.
Development a practicum tools to measure the speed of the air using Arduino Uno Microcontroller
Authors: Indrasari W , Rustana C E , Zulfikar
Published: March 2021

This study aims to produce practicum tools that can measure the speed of the air. This tool uses the HC-SR04 ultrasonic sensor module as a sound wave transmitter and uses the Arduino UNO as a control system. The research method used is ADDIE. After the product has been developed, it is evaluated by conducting a validation test. Based on validation results, this practicum tool’s suitability has also been validated by the media expert. The following is the score achieved from each of the indicators, distance and time measurement score was 75%, appearance of practicum tool data was 100%, and clarify the concept was 75%. Therefore, the practicum tools as learning media to measure the air’s speed are fit for use.
Analysis of the radiation parameters of pumice constituent compounds using XCOM
Authors: Wirawan R , Qomariyah N , Ardianto T , Kurniawidi D W
Published: March 2021

In this study, analysis of radiation parameters (linear attenuation coefficient, mean free path and half value layer) of pumice constituent compounds was carried out. Analyzes were done on the compounds of Al2O3, Fe2O3, SiO2, CaO, K2O and Na2O with a theoretical approach using the XCOM program for gamma photon energies 57Co (0.122 MeV; 0.1365 MeV), 133Ba (0.356 MeV), 54Mn (0.835 MeV), 137Cs (0.662 MeV), 60Co (1.173 MeV; 1.333 MeV), 65Zn (1.1155 MeV), 22Na (0.511 MeV; 1.275 MeV) and 40K (1.461 MeV). The results show that the Fe2O3 compound has the largest linear attenuation coefficient, while the largest for MFP and HVL is Na2O among other compounds.
Ultrasonic Method as a Tool for Geotechnical Parameters Estimation at Proposed Engineering Site/Western Iraq
Authors: Al-Awsi Munther D. , Khorshid Salman Z. , Ahmed Muaiad T.
Published: March 2021

The objective of the present research is to confirm the possibility of ultrasonic methods as geophysical tool for the estimating of geotechnical parameters for engineering purposes. Thirty seven (37) rock samples were collected at different depths of borehole drilled at the study area, and both primary and secondary waves velocity (Vp and Vs) were measured in laboratory. To evaluate the rock competence as foundation material for engineering works, some important geotechnical parameters including Poisson’s ratio(σ), Stress Ratio(Si), Material index(Im), Concentration index(Ic), and Density gradient( Di) were calculated. The obtained results demonstrate that the first surface layer is characterized by incompetent to fairly competent materials, the second layer (Anah Formation) is characterized by alternation of the moderately competent ( limestone) with thin incompetent (coralline limestone) layer, while the third layer (Baba Formation ) which composed of dolamatic limestone is characterized by good geotechnical parameters, reflect good competent rocks representing more suitable rocks as foundation layer for civil engineering constructions at the investigated site. The results also confirm the efficiency of ultrasonic method in estimating and assessing the geotechnical parameters of rock samples in pre-construction studies.
A Certain Conditions on Some Rings Give P.P.Ring
Authors: Abed Majid Mohammed , Al-Sharqi Faisal , Zail Saad H.
Published: March 2021

Many new results were obtained in this paper about P.P. ring. Semi-primitive ring R with (dcc) on principal-ideal P is always P.P.ring. Also, St-G-P.P. ring R is given to answer new question; is B-rings are P.P. ring. Also regular and Von Neumann regular rings are introduced to find a relationship between P.P. ring and these kind of the rings.
(β, α)-Fuzzy Magnified Translations of AT-algebra
Authors: Hameed Areej Tawfeeq , Malik Nada Hadi
Published: March 2021

Magnified translation of fuzzy AT-subalgebras and fuzzy AT-ideals on AT-algebras are discussed. Relations among magnified translations, them are investigated.
Effect of Molecular Weight on Electro – Optic Switching Times of Liquid Crystal Polymer Doped with Ceo2 Nanoparticles
Authors: Hussein Alaa A. , Al-Ammar Khalid
Published: March 2021

Nonlinearity liquid crystal cell which doped with Ferroelectric nanoparticles characters studied in this paper according to their eclectic absorption. Polysiloxin series with side chain liquid polymers used with side chain polymers and molecular weight ran This study consternate on polymers electro. optic characteristic with various molecular weights by using the mesogenic units and a stable polysiloxane. Suspension sensitivity or Electro-visual response to the mark of the used electric field, a real character to electric liquid crystals. The addition of CeO2, nanoparticles to polymer rise dielectric anisotropy and minimize response times. It observed that the voltages raised with molecular weight rising, and when intensity value rise, we gain voltage operating. Spectrometer used infrared measurements to locate the orientational order parameters,

(

S

¯

)

for liquid crystals with a side series. The orientational order parameters

(

S

¯

)

rely on temperature with various molecular weights and the threshold voltage.
A Study of Preparing Samples of Hydroxyapatite with Different Densities Using Charcoal Powder
Authors: Saeed Ghazi K. , Essa Abbas F , Said Saja Abdul-Ammer
Published: March 2021

The powder of hydroxyapatite with the chemical formula Ca10(PO4)6(OH)2was prepared locally from cow bones in the hexagonal crystal phase, and this was confirmed through the X-ray diffraction system. The proportions that formed the prepared hydroxyapatite were confirmed through the X-ray fluorescence system and found the ratio of calcium oxide to phosphorous oxide is 1.718. The hexagonal phase of the prepared hydroxyapatite was also stabilized ( fixed ) for the samples before and after the heat treatment. Some physical and mechanical properties were also conducted for the prepared samples. It was found that it is possible to prepare samples of different densities by adding different proportions of carbon (charcoal) percentage to the prepared hydroxyapatite.
Solving the Nonlinear Monotone Equations by Using a New Line Search Technique
Authors: Hashim K. H. , Hashim L H , Dreeb N k , Shiker Mushtak A. K.
Published: March 2021

In this work a new technique of line search is proposed to solve the nonlinear monotone equations. For this purpose we combine a modified line search rule with monotone technique. The new proposed algorithm can decrease the CPU time, the number of iterations and the functions evaluations and can increase the efficiency of the approach. The global convergence result of the recommended procedures is established under some standard conditions. Preliminary numerical results indicate that the proposed algorithm are interesting and remarkably promising.
Model Parameterization for Coherent Manipulation in Spin Current through FM-QD1-QD2-FM
Authors: Najdi M. A. , Al-Mukh J. M. , Jassem H. A.
Published: March 2021

In this work, model parameterization for coherent manipulation, for serially coupled double quantum dots embedded between ferromagnetic leads (FM-QD1-QD2-FM), is presented. Theoretical model based to the non-equilibrium Green’s function approach is considered. Since the spin current and its spin channels are formulated incorporating the spin polarization and the type of spin configuration on the leads. Our model incorporates the inter-dot hopping, the intra-dot Coulomb correlation, the spin exchange energy and the coupling interactions between the quantum dots and leads. The results concerned to the parallel configuration at strong inter-dot coupling regime shows the preferable coherent state for spin down electrons only at relatively high polarization. While, for weak coupling regime and antiparallel configuration, the decoherent state is dominating. Interesting results have been concluded by calculating the molecular energy levels of the quantum dots. In all our calculations the same spin polarization on the leads is considered. The case of different spin polarization on the lead is also investigated but no unprecedented features are concluded as active region is symmetric.
A New Shifted Conjugate Gradient Method”Based”on Shifted Quasi-Newton Condition
Authors: Jameel Marwan S , Abdullah Zeyad M , Fawzi Firas A , Hassan Basim A
Published: March 2021

In this article, the shifted quasi-Newton condition used to suggest a new shifted conjugate gradient method (CGM). The method of Idea and Zhang’s et al had been compounding to introduce a modren shifted conjugate gradient method (NSCGM). The propose style based on a hybrid the CGM with a shifted quasi-Newton conditions in which generate descent search direction. The global convergence properties will be hold by the proposed method. The proposed method obtained encourage results that compared with other methods in the literatures.
A Stochastic Differential Equations Model for Internal COVID-19 Dynamics
Authors: Kareem Ahmed M. , Al-Azzawi Saad Naji
Published: March 2021

In this article, we analyze stochastic differential equations model for internal coronavirus (COVID-19) dynamics. The stochastic differential equations model are expressed using the Ito’s formula. The Environmental stochasticity in this dynamical model is presented via parameters disturbance which is the standard method in the stochastic differential equations(SDEs) in the population modeling. We than prove that this model decided in this paper have a unique global positive solution because this is fundamental in any population dynamics model. The main aim of this paper, we formulate the interaction of coronavirus COVID-19 with host cells and presented the conditions required in order to the COVID-19 to die out. And this results also illustrated by computer simulation.
On the Bridge Between Computational Results Of New Line Search Technique
Authors: Al-Shimari Nofl Sh. , Jumaa Basim Rabaa , Al-Jilawi Ahmed Sabah.
Published: March 2021

The goal of this paper is to find a better linesearch technique and different combinations of optimization and linesearch algorithms. Line searchtechnique on the off chance that it looks for the base of a descent direction vector that, when processed iteratively with a sensible advance size.
Optimization of Poly (vinyl chloride) Surface Modification with an Aromatic Schiff Base-Ni (II) Complex as Photostabilizer
Authors: Hadi Angham G. , Saddam Nahlah Salman , Ahmed Dina S. , Yousif Emad
Published: March 2021

Though PVC is one of the most common synthetic polymers that differ from their analogues in low molecular weight alkyl halides in that they do not readily demonstrate the effects of simple nucleation. Chlorine removal is preferred in many condensation reaction situations, and the creation of the following double bond guarantees dark colored products. The chemical adaptation of poly (vinyl chloride) (PVC) with new functional thiol compound has been reported. A homogenous blend has been inserted to nickel chloride; the polymeric film were exposed to ultraviolet light for 300 hours. The structural changes in the modified film were observed by FTIR spectroscopy and losing in weight; the morphology of surface has been examined by optical microscope.
Map of Mode Hopping Associated with Modulated Laser Diode Under Feedback and Injection
Authors: Abbas Rasha Salah , Hemed Ayser A.
Published: March 2021

A new simple technique for narrow-linewidth and wavelength-tunable laser is experimentally satisfied. The technique is based on employing nonlinearities arise with laser feedback and injection. The main effect observed and controlled is the mode hopping (MH) within other nonlinearities. In this situation mixed optoelectronical feedback (OEFB) and optical injection from another identical type laser simultaneously, plays the role of controller. These results show that no need of using a Fiber Bragg Grating. As a well-known alternative technique used earlier to build a tunable laser. The map of validity for this effect and parameters affecting the laser output are all investigated. This technique enhances modulation index for the slave laser to be 100% and employs mode hoping generated in it for tuning output lasing frequency. This is by controlling either master laser detuning or injection strength or both. Also, by controlling slave laser optoelectronic feedback time delay (by a variable RF attenuator) or (and) nonlinear contribution for this by introducing a nonlinear function into the detected signal. Bidirectional (mutual) and unidirectional injection systems are experimented. In the first system both lasers multi-lasing in general synchronization manner, while in the last system, injector (master) laser stays immune from slave dynamics.
An Application Comparison of Two Poisson Models on Zero Count Data
Authors: Hashim L. H. , Hashim K. H. , Shiker Mushtak A. K.
Published: March 2021

Counting data (including zero counts) appear in a variety of applications, so counting models have become popular in many fields. In statistical fields, count data can be defined as observation types that use only non-negative integer values. Sometimes researchers may Counts more zeros than the expected. You may describe Excess zero as Zero-Inflation, excess zeros cause over-dispersion. So, the objective of this paper is use zero-inflated regression models (Poisson Regression model, Zero-Inflated Poisson (ZIP), and Zero-Altered Poisson (ZAP)) to analyse rainfall data and select the best model that deal with these type of data. It has been shown through the study and practical application that the advantage and quality of the Zero-Altered Poisson Regression (ZAPR) where the Zero-Altered Poisson regression model was the best count data model for our data, Although it is hard to distinguish Zero-Inflated Poisson (ZIP) regression model, it is better than Poisson regression model.
Low-Cost Pressure Sensors Fabricated from Novel Polymeric Nanocomposites
Authors: Jalil Hussien Huda Abdul , Kadhim Raheem G. , Hashim Ahmed
Published: March 2021

Nanocomposites (NCs) can be used in several fields, for example, solar cells, biosensors, diodes, antibacterial, transistors…etc. In this paper,(poly (ethylene oxide)-polyvinylpyrrolidone-silicon oxide nanoparticles-manganese dioxide nanoparticles) NCs have been manufactured for pressure sensors with low weight, high sensitivity and lowcost. The nanocomposites were made up of various concentrations of poly (ethylene oxide) (PEO)-polyvinyl pyrrolidone (PVP)-silicon dioxide nanoparticles (SiO2 NPs) and manganese dioxide nanoparticles (MnO2 NPs). The electrical conductivity and dielectric properties of the nanocomposite are studied at room temperature. The dielectric properties of the NCs are examined in the frequency range (100 Hz–5 MHz). The AC electrical conductivity, dielectric constant, and dielectric losses increase with the weight percentages of MnO2 NPs. The dielectric constants and dielectric losses decrease when a frequency increases. The A. C electrical conductivity increases with the concentration of MnO2 NPs and the frequency. The nanocomposite was tested for the pressure sensors application in the pressure range (80–160) bar. The experimental results show that the electric capacitance of nanocomposites samplesis increased, as the pressure increases. Also, the electric capacitance of NCs increases with an increase in the weight percentages of MnO2 NPs. The NCs has a high sensitivity to pressure.
The Bifurcation Analysis and Persistence of the Food Chain Ecological Model with Toxicant
Authors: Majeed Azhar Abbas , Kadhim Atheer Jawad
Published: March 2021

In this work, the occurrence conditions of both local Bifurcation and persistence were studied, Saddle-node bifurcation appears near fourth point, near the first point, the second point and the third point a transcritical bifurcation occurred but no pitchfork bifurcation happened near any of the four equilibrium points. In addition to study conditions for Hopf-bifurcation near positive stable point that is the fourth point. Besides discuss persistence occurrence as globally property of the food chain of three species include prey, first predator and top predator with impact of toxin in all species and harvesting effect on the predator’s only. Numerical results for the set of hypothetical of parameters come to confirm our analytical results about illustration the occurrence of local bifurcation and persistence of this model.
A Systematic Review of Data Aggregation Techniques in Wireless Sensor Networks
Authors: Idan Saeedi Iman Dakhil , Al-Qurabat Ali Kadhum M.
Published: March 2021

A Wireless Sensor Network (WSN) consists of a number of sensor nodes which can sense, communicate, and store data, and it has a battery capacity. Data aggregation can be defined as a procedure applied for the elimination of redundant transmissions, and it provides fused information to the base stations, that in turn improve the energy effectiveness and increases the life span of energy constrained WSNs. The current article presents a systematic review of data aggregating schemes in flat and hierarchical WSNs, which are compared in light of different factors, including the node heterogeneity, mobility of aggregator nodes, and types of networks and algorithms. By comparing these remarkable techniques, a set of aspects are suggested to be dealt with in future works. Index words: Data aggregation, WSNs, network lifetime, Flat Network, Hierarchical network.
The Implementation of the Trapezoidal Fuzzy Number toward the Solution of the A Fuzzy Inventory Model with Shortages
Authors: Iswarya T. , Karpagavalli SG.
Published: March 2021

In this paper, fuzzy inventory model with shortages has been considered. Trapezoidal fuzzy number with Weibull distribution is used to fuzzify the data of an inventory model. All the parameters used in the inventory model is converted to trapezoidal fuzzy numbers using function principle. We find the estimate of the total inventory cost by defuzzifing the trapezoidal fuzzy numbers using the the graded mean integration. The optimum total cost for the inventory model is found.
Radiological Risk Assessment of Oil waste in the Oilfields at Zubair district of Basrah
Authors: Khudheir Mohammed
Published: March 2021

The specific activities of natural radionuclides in several samples were collected from the areas that exposed to triple-aggression which is Zubair province at Basrah governorate exactly. Those samples were studied and that concentrations calculated by using Gamma spectrometry system based on HpG detector with efficiency 40% was used for analysis of NORM. Then radiological risk of the natural radioactivity was estimated for study area that caused from exist the radionuclides in surface soil and water samples. The results have been revealed the contamination that occurring in some sites of Zubair district belonging to the natural radioactive material. Activity concentrations in Bq/kg of 238U, 232Th, and 40K with mean values of 95.8 Bq/kg, 31.6 Bq/kg, and 482.18 Bq/kg respectively. The outcome of soil samples were appeared higher values when compared with international calibrations. Whereas the results of Gamma absorbed dose (nGry/h), the exposure dose rate (µR/h) have mean values non-detected like; 52.5, 12.8 respectively, where under the international average by UNSCEAR 2008. Since the Radium equivalent activity (Ra-eq) has value 295.8 Bq/kg is higher than the standardizations.
Unmanned Aerial Vehicle (UAV) Application for Updating of Urban Database
Authors: Trung Le Van , Nhat Nguyen Huu , Nhut Mai Cong
Published: March 2021

This paper describes a new approach for urban land use management by using Unmanned Aerial Vehicles (UAV). Experimental result covers 121 ha (1.21 km2) at Binh Tho ward, Thu Duc district of the Ho Chi Minh city and shows that UAV technology is most suitable and cost effective for cadastral mapping and updating the database with high accuracy. In this research, 36 GCPs (Ground Control Points) and 2433 parcel boundaries (GIS data) were used to compare the achieved accuracy of UAV method in which 10381 orthophoto imageries produced had a resolution of 1.8 cm (with flying altitude 70 m) to be used to inform urban database. This technology opens a new way that is most suitable and cost effective for small areas, where digital maps and 3D models need to be produced in a short period of time with high data quality and accuracy. There are no significant barriers to imbed the technology at the local level and it can speed up the process of updating database in developing the Spatial Data Infrastructure (SDI) of the smart city.
Sustainable Urban Drainage System Model for The Nhieu Loc – Thi Nghe Basin, Ho Chi Minh City
Authors: Dung Le Thi , Phu Vo Le , Lan Nguyen Hoang My , Tien Nguyen Thi Cam , Hiep Luu Dinh
Published: March 2021

In recent years, Ho Chi Minh City has been faced with stark challenges in urban flooding affected by the impact of climate change in associated with the rapid urbanization and unadequate urban planning. Although many flood mitigation solutions were invested and implemented such as upgrading drainage systems, transport infrastructure, flood control pumps, etc. the problem remains unsolved and even worse. The purpose of this study is to propose a calculation model of the sustainable urban drainage system (SuDS) integrated with of GIS and remote sensing technology to assess and predict flooding degree in a specific basin in HCMC. Further, the results of this calculation model are just a pre-testing and pre-simulation of the proposed model for future studies on the application of sustainable urban drainage techniques, including rainwater harvesting, green roofs, urban green space and pervious pavement.
Developing Integrated Index for Evaluating the Urban Natural Environmental Quality from Remote Sensing Technology
Authors: Phuong Dinh Thi Kim , Ha Nguyen Ngan , Han Tham Thi Ngoc , Van Tran Thi
Published: March 2021

Environmental quality (EQ) has always been paid more attention in big cities, where urbanization is on the rise because it greatly affects urban natural ecosystems and people’s health. The paper presents the results of applying Landsat satellite images to evaluate the Natural Environmental Quality (NEQ) from the integrated index NEQI (Natural Environmental Quality Index) through the calculation of biophysical variables, including vegetation index NDVI, water surface index NDWI, construction index NDBI and land surface temperature LST. The study area is the north of Ho Chi Minh City (HCMC), divided into 3 sub-regions for analysis, including 13 old inner-city districts, 6 new inner-city districts, and 4 suburban districts. The results showed that there is a difference in NEQI between inner and suburban areas. Low NEQI is concentrated in urban areas with high urbanization rate, industrial zones, areas with large impervious surface areas and low greenery density. In the suburbs, in contrast, NEQ is better than in the inner city. If considering by the acquisited time of two satellite images in February of 2005 and 2020, the NEQ of the study area showed signs of decreasing and gradually expanding area from the inner city to the suburbs. Particularly in the suburbs, due to the urbanization process in recent years, there are spontaneous and unplanned development areas, so NEQ has changed towards a decrease. The results of the study can be used to support urban environmental planning and management.
Assessment of meteorological drought in the Vietnamese Mekong delta in period 1985-2018
Authors: Quang C N X , Hoa H V , Giang N N H , Hoa N T
Published: March 2021

Drought is one of a major natural disaster that causes tremendous damage to the ecological environment and social-economic in the Vietnamese Mekong Delta (VMD). Drought characteristics are invaluable knowledge for better management of water resources and agriculture production, especially under climate change context. This study investigated the spatiotemporal trend, intensity, duration, and frequency of meteorological droughts over VMD by using the Standardized Precipitation Evaporation Index (SPEI). The SPEI at multiple time scales (3, 6 and 12 months) are determined by using the monthly precipitation and temperature data between 1985 and 2018 obtained from ten meteorological stations in VMD namely Ba Tri, Cang Long, Soc Trang, Bac Lieu, Rach Gia, Ca Mau, Chau Doc, Can Tho, Cao Lanh, and My Tho. SPEI detected ten extreme drought events from 1985-2018 that matches with the historical extreme drought events reported in VMD. It means SPEI could be a useful indicator to support for drought management and mitigation in the future. The extreme drought event from October 2013 to September 2016 was the highest intensity and most prolonged duration from 1985-2018. The El Niño is considered to strongly influence on extreme drought events in VMD as all extreme drought events are highly associated with El Niño periods. The intensity, duration and frequency of drought events increased from 1985 to 2018. Drought events are more severe in VMD in recent years. Extreme drought also tends to cover for over VMD region. Adaption measures are essential to cope with drought disaster, especially in the agricultural and aquacultural sectors.
Mapping Land use/land cover using a combination of Radar Sentinel-1A and Sentinel-2A optical images
Authors: Nguyen T T H , Chau T N Q , Pham T A , Tran T X P , Phan T H , Pham T M T
Published: March 2021

The current study used a combination of Sentinel-1A (SE-1A) radar and Sentinel-2A (SE-2A) optical images in mapping land use/land cover (LULC) in Dak Nong province in 2018. The Random Forest (RF) algorithm was adopted to digitally categorize Landsat images into LULC maps according to ten different LULC classes included: evergreen forest, semi-evergreen forest, deciduous forest, plantation, rubber, industrial plants, crop land, residential area, water surface and others. The results indicated an overall accuracy (OA) and kappa coefficient of 81.40%, Kappa = 0.79, respectively. Based on the results of classified image, a 2018 LULC map of the study area was simulated. Accordingly, the natural forests account for 34.27% of the total area of the province, distributed scattered in districts. In which, the evergreen forest occupies the highest area with more than 166.600 ha, equivalent to 74.54% of the total natural forest area, and concentrated in the high mountain areas. Non-forest covers occupy more than 63% area of Dak Nong province. The industrial and agricultural cropland indicated a high area in the study area with a rate of 34.82% and 11.38%, respectively. This shows a strong development in the scale of industrial and agricultural crops in the study area. The objective information on current land use/land cover in this study can serve as the basis for policymakers to orient the local forest resource sustainability strategies. Besides, the study also shows that the use of a combination of Sentinel-1A radar and Sentinel-2A optical image to classify and construct the LU/LC map is a high-efficiency research direction.