bluuebunny/crossref_metadata_2025 huggingface dataset:
H2 Rovibrational Excitation in Protoplanetary Disks and Its Effects on the Chemistry
Authors: Ruaud Maxime
Published: August 2021

The effect of H2 rovibrational excitation on the chemistry of protoplanetary disks is studied using a framework that solves for the disk physical and chemical structure and includes a detailed calculation of H2 level populations. Chemistry with rovibrationally excited H2 is found to be important for the formation of several commonly observed species in disks and this work demonstrates the need to accurately treat photon-dominated-region chemistry in disks if we are to make inferences on the chemical state of the disk during planet formation epochs. This is found to be even more critical for molecules like C2H, CN, or HCN that are commonly used to infer changes in the elemental disk C/O and N/O ratios, with implications for planetesimal formation and the composition of exoplanet atmospheres. Computed vertical column densities with the full H2 population calculation are increased by ∼1–2 orders of magnitude for molecules such as CN and HCN/HNC compared to calculations with no treatment of excited H2. For the commonly used pseudo-level approximation, the computed columns of these molecules are overestimated by a factor of ∼3–5 when compared to the full model. We further note that the computed abundance for these molecules strongly depends on the strength of the FUV photons at energies that pump H2 (i.e., 11–13.6 eV), which is not well constrained in disks, and that rate constants as a function of H2 rovibrational levels for the key reaction N + H2 → NH are needed for a more accurate assessment of CN/HCN chemistry but are currently unavailable.
Dynamical Model of the Milky Way Using APOGEE and Gaia Data
Authors: Nitschai Maria Selina , Eilers Anna-Christina , Neumayer Nadine , Cappellari Michele , Rix Hans-Walter
Published: August 2021

We construct a dynamical model of the Milky Way disk from a data set that combines Gaia EDR3 and APOGEE data throughout galactocentric radii in the range 5.0 kpc ≤ R ≤ 19.5 kpc. We make use of the spherically aligned Jeans anisotropic method to model the stellar velocities and their velocity dispersions. Building upon our previous work, our model is now fitted to kinematic maps that have been extended to larger galactocentric radii due to the expansion of our data set, probing the outer regions of the Galactic disk. Our best-fitting dynamical model suggests a logarithmic density slope of α
DM = −1.602 ± 0.079syst for the dark matter halo and a dark matter density of ρ
DM(R
⊙) = (8.92 ± 0.56syst) × 10−3
M
⊙ pc−3 (0.339 ± 0.022syst GeV cm3). We estimate a circular velocity at the solar radius of v
circ = (234.7 ± 1.7syst) km s−1 with a decline toward larger radii. The total mass density is ρ
tot(R
⊙) = (0.0672 ± 0.0015syst) M
⊙ pc−3 with a slope of α
tot = −2.367 ± 0.047syst for 5 kpc ≤ R ≤ 19.5 kpc, and the total surface density is Σ(R
⊙, ∣z∣ ≤ 1.1 kpc) = (55.5 ± 1.7syst) M
⊙ pc−2. While the statistical errors are small, the error budget of the derived quantities is dominated by the three to seven times larger systematic uncertainties. These values are consistent with our previous determination, but the systematic uncertainties are reduced due to the extended data set covering a larger spatial extent of the Milky Way disk. Furthermore, we test the influence of nonaxisymmetric features on our resulting model and analyze how a flaring disk model would change our findings.
Outflow Bubbles from Compact Binary Mergers Embedded in Active Galactic Nuclei: Cavity Formation and the Impact on Electromagnetic Counterparts
Authors: Kimura Shigeo S. , Murase Kohta , Bartos Imre
Published: August 2021

We propose a novel scenario for possible electromagnetic (EM) emission by compact binary mergers in the accretion disks of active galactic nuclei (AGNs). Nuclear star clusters in AGNs are a plausible formation site of compact-stellar binaries (CSBs) whose coalescences can be detected through gravitational waves (GWs). We investigate the accretion onto and outflows from CSBs embedded in AGN disks. We show that these outflows are likely to create outflow cavities in the AGN disks before the binaries merge, which makes EM or neutrino counterparts much less common than would otherwise be expected. We discuss the necessary conditions for detectable EM counterparts to mergers inside the outflow cavities. If the merger remnant black hole experiences a high recoil velocity and can enter the AGN disk, it can accrete gas with a super-Eddington rate, newly forming a cavity-like structure. This bubble can break out of the disk within a day to a week after the merger. Such breakout emission can be bright enough to be detectable by current soft X-ray instruments, such as Swift-XRT and Chandra.
Statistical Properties of Small-scale Linear Magnetic Holes in the Martian Magnetosheath
Authors: Wu Mingyu , Chen Yangjun , Du Aimin , Wang Guoqiang , Xiao Sudong , Peng E. , Pan Zonghao , Chen Yuanqiang , Zhang Tielong
Published: August 2021

The small-scale linear magnetic hole (LMH) is a magnetic dip with a size less than or on the order of ρ

i
(proton gyroradius), which may contribute to turbulence properties in the solar wind and other astrophysical plasmas. Based on one-month measurements of the Mars Atmosphere and Volatile EvolutioN mission, 174 small-scale LMH events in the Martian magnetosheath are used to investigate their statistical properties in this study. Our results show that small-scale linear LMHs are ubiquitous in the Martian magnetosheath, and their occurrence rate is estimated to be approximately 1.5 events per hour based on one-month observations. Compared with the ambient plasma, the averaged magnitude of the magnetic field in these holes can decrease from 6.8–3.5 nT. Nearly 66% of events have a B
min/B value in the range of (0.45, 0.75). The duration of small-scale MHs is mainly less than 0.4 s. For 90% of the events, the size along the solar wind flow is less than ρ

i
. As the rotation angle increases, the occurrence rate of small-scale LMHs decrease. However, the B
min/B, size, and duration of small-scale LMHs have no obvious dependence on their rotation angle.
Exploring the use of micro-computed tomography (micro-CT) in the taxonomy of sea cucumbers: a case-study on the gravel sea cucumber Neopentadactyla mixta (Östergren, 1898) (Echinodermata, Holothuroidea, Phyllophoridae)
Authors: Samyn Yves , Sonet Gontran , d'Acoz Cedric d'Udekem
Published: August 2021

Sea cucumber taxonomy and systematics has in the past heavily relied on gross external and internal anatomy, ossicle assemblage in different tissues, and molecular characterisation, with coloration, habitat, and geographical and bathymethric distribution also considered important parameters. In the present paper, we made these observations and techniques in detail and complemented them with the novel technique of micro-computed tomography of the calcareous ring. We investigated a single European species, the so-called gravel sea cucumber,Neopentadactyla mixta(Östergren, 1898), using recently collected material from the Chausey Islands, Normandy, France. We redescribed the species, illustrated its ossicle assemblage through scanning electron microscopy, and visualised the calcareous ring through stacking photography and through micro-CT scanning. Additionally, a DNA fragment of 955 base pairs of the 18S ribosomal RNA gene was sequenced from one specimen, which showed a high similarity with the only sequence ofN. mixtapublicly available. We completed this integrative study by providing a detailed distribution of the occurrence ofN. mixtabased on published, verifiable accounts.
Reflections of Family Nurse Practitioner Students During the COVID-19 Pandemic: A Qualitative Study
Authors: Link Tamara , Laham Kelly , Hubbell Sara , Baisden Paula
Published: August 2021

Background:

To understand family nurse practitioner (FNP) students' academic experience during the COVID-19 pandemic, faculty developed an online reflective discussion board assignment. The richness of the responses prompted faculty to gather data and analyze themes.

Method:

The purpose of this qualitative study was to explore the perspectives of FNP students regarding the impact of COVID-19 on their academic experience. Participants were asked to answer four open-ended questions in a discussion board to address the research question. Responses of consenting students were analyzed qualitatively using open, axial, and selective coding.

Results:

Four main themes emerged: worry and fear, cyclical stress, mitigation of stress, and personal growth of resilience and empathy. Students emphasized that faculty support strategies mitigated stress and anxiety.

Conclusion:

Understanding students' experience is crucial to facilitating academic success. Faculty in similar situations could better support their students through clear communication, and providing flexibility and opportunities for self-reflection.

[
J Nurs Educ
. 2021;60(8):449–452.]
Nursing Students Behind Bars
Authors: Clark Kimberly , Falk Mary
Published: August 2021

Background:

With a large incarcerated patient population in the United States, there is a unique potential for clinical learning for undergraduate nursing students with this population.

Method:

The Virginia Commonwealth University (VCU) School of Nursing and VCU Health System have created a unique partnership in which baccalaureate nursing students complete their first clinical rotation on VCU Health System's Secure Care Unit (SCU). At the conclusion of their semester, baccalaureate students assigned to the SCU for the fundamentals clinical were asked to provide feedback on their experiences.

Results:

Both challenges and positive outcomes were identified by students who completed their first clinical rotation providing care to this unique population.

Conclusion:

The formation of this relationship between the VCU School of Nursing and the VCU Health System's SCU is helping to meet patient, student, and clinical unit needs and also making a positive impact on the stakeholders involved.

[
J Nurs Educ.
2021;60(8):470–471.]
Analysis of the role of METTL5 as a hub gene in lung adenocarcinoma based on a weighted gene co-expression network
Authors: Yan Xinwang ,   Medical College of Qingdao University, Jining NO.1 People's Hospital, Qingdao, Shandong Province 266042, China, Zhao Xiaowen , Yan Qing , Wang Ye , Zhang Chunling ,   Clinical Laboratory, Qingdao Central Hospital, The Second Affiliated Hospital of Medical College of Qingdao University, Qingdao, Shandong Province 266042, China
Published: August 2021

Lung adenocarcinoma (LUAD) is a frequently diagnosed malignant tumor that is highly invasive and lethal. The prognosis of patients with LUAD still needs to be improved, as conventional treatment is remarkably well tolerated. In this study, the expression profile of LUAD in the TCGA database was used for differential expression analysis, and differential expression genes were determined to construct a weighted gene co-expression network analysis (WGCNA) for dividing and finding the gene modules with the highest correlation with tumor stage. Here, METTL5, DDX23, GPSM2, CEP95, WDCP, and METL17 were identified as hub genes. According to the relation degree, METTL5 was determined as the candidate gene in this study. Difference analysis and receiver operating characteristic (ROC) curve were applied to identify the predictive performance of METTL5 in LUAD, and Kaplan-Meier (KM) analysis showed that the prognosis of LUAD patients with high METTL5 expression was poor. Further GSEA analysis showed that high-expressed METTL5 was related to epithelial-mesenchymal transition and other pathways. Therefore, METTL5 may be involved in the occurrence and malignant progression of LUAD. The current findings provide an effective molecular target for early diagnosis of LUAD, helping monitor the malignant progression of LUAD and improve the prognosis of LUAD patients.
Unplugged Learning
Authors: Relkin Emily , Strawhacker Amanda
Published: August 2021

This chapter explores perspectives on unplugged coding and computational thinking (CT) in early childhood. Concepts, definitions, and research on unplugged learning and its relationship to computer science are considered. Several examples illustrate how young children can encounter powerful ideas of CT in both formal educational settings and in the process of everyday life. Resources are provided that aid in the identification and integration of unplugged activities into early childhood settings. Finally, the authors advocate for further research on teaching CT concepts to children that includes both coding and unplugged approaches.
Including Students With Disabilities in the Coding Classroom
Authors: Levinson Tess , Hunt Libby , Hassenfeld Ziva Reimer
Published: August 2021

This chapter discusses understandings of coding and computational thinking education for students with disabilities. The chapter describes the special education system in the United States, including limitations in how computer science education is made available to students receiving special education services. The chapter then provides a summary of research in computer science education for students with disabilities, including both high-incidence and low-incidence disabilities. A case study of a young student with a mild disability learning in a general education computational thinking program is then presented, and the implications of the case study for future research directions are discussed.
Fluorine-Free Durable Superhydrophobic Surfaces Fabricated via a Simple Spraying Method
Authors: Xu Zhi Yong , Wang Yan Yan , Tang Xing Jie , Peng Chang Si
Published: August 2021

Superhydrophobic self-cleaning surfaces are based on the surface micro/nanomorphologies and special chemical regents with low surface free energy. Such surface structures are highly susceptible to mechanical wear. Moreover, the use of fluorinated compounds is harmful to both human health and environment. Herein, a simple method based on spin coating and spraying is proposed to fabricate durable fluorine-free superhydrophobic surfaces. A glass substrate was coated with a layer of water-based paint via a simple spinning process. Due to the adhesive layer, modified SiO2 nanoparticles were strongly bonded to the glass substrate. After the coating was completely cured, the surfaces realized a water contact angle of 165.1° and maintained their water repellency after 50 abrasion cycles with sandpaper and 50 times of stripping test. No chemical reagents harmful for the environment were used.
Swelling Behaviour and Water Vapour Transmission Rates of Gellan Gum/Collagen Film Containing Gatifloxacin as Dressing Materials
Authors: Abu Bakar Aznatul Jannah , Mat Amin Khairul Anuar
Published: August 2021

In an effort to produce ideal wound dressing, gellan gum/collagen hydrogel films containing different concentrations of gatifloxacin were prepared via evaporative casting method. The films were examined in terms of physical appearances, water uptake and water vapour transmission rate (WVTR). All the films showed good physical appearances. Swelling percentages of the films were decreased, whereas WVTR values were increased as the addition of gatifloxacin was increased. Swelling percentage of gellan gum/collagen film with the lowest percentage of gatifloxacin (GG/C-GAT01) has the highest swelling ratio (2057%). Meanwhile, the WVTR value of GG/C-GAT1 has the highest WVTR value among all films which is 1245 g m-2 day-1. The formulation of GG/C films with the addition of gatifloxacin with good water absorbance and acceptable WVTRs value offered promising materials to be applied as wound dressing materials.
Activation of Transcription Factor 4 in Dendritic Cells Controls Th1/Th17 Responses and Autoimmune Neuroinflammation
Authors: Manoharan Indumathi , Swafford Daniel , Shanmugam Arulkumaran , Patel Nikhil , Prasad Puttur D , Thangaraju Muthusamy , Manicassamy Santhakumar
Published: August 2021

Dendritic cells (DCs) are professional APCs that play a crucial role in initiating robust immune responses against invading pathogens while inducing regulatory responses to the body's tissues and commensal microorganisms. A breakdown of DC-mediated immunological tolerance leads to chronic inflammation and autoimmune disorders. However, cell-intrinsic molecular regulators that are critical for programming DCs to a regulatory state rather than to an inflammatory state are not known. In this study, we show that the activation of the TCF4 transcription factor in DCs is critical for controlling the magnitude of inflammatory responses and limiting neuroinflammation. DC-specific deletion of TCF4 in mice increased Th1/Th17 responses and exacerbated experimental autoimmune encephalomyelitis pathology. Mechanistically, loss of TCF4 in DCs led to heightened activation of p38 MAPK and increased levels of proinflammatory cytokines IL-6, IL-23, IL-1β, TNF-α, and IL-12p40. Consistent with these findings, pharmacological blocking of p38 MAPK activation delayed experimental autoimmune encephalomyelitis onset and diminished CNS pathology in TCF4ΔDC mice. Thus, manipulation of the TCF4 pathway in DCs could provide novel opportunities for regulating chronic inflammation and represents a potential therapeutic approach to control autoimmune neuroinflammation.
RACK1 T50 Phosphorylation by AMPK Potentiates Its Binding with IRF3/7 and Inhibition of Type 1 IFN Production
Authors: Qin Cheng , Niu Chunxiao , Shen Zhuo , Zhang Yaolin , Liu Genyu , Hou Chunmei , Dong Jie , Zhao Min , Cheng Qianqian , Yang Xiqin , Zhang Jiyan
Published: August 2021

The receptor for activated C kinase 1 (RACK1) adaptor protein has been implicated in viral infection. However, whether RACK1 promotes in vivo viral infection in mammals remains unknown. Moreover, it remains elusive how RACK1 is engaged in antiviral innate immune signaling. In this study, we report that myeloid RACK1 deficiency does not affect the development and survival of myeloid cells under resting conditions but renders mice less susceptible to viral infection. RACK1-deficient macrophages produce more IFN-α and IFN-β in response to both RNA and DNA virus infection. In line with this, RACK1 suppresses transcriptional activation of type 1 IFN gene promoters in response to virus infection. Analysis of virus-mediated signaling indicates that RACK1 inhibits the phosphorylation of IRF3/7. Indeed, RACK1 interacts with IRF3/7, which is enhanced after virus infection. Further exploration indicates that virus infection triggers AMPK activation, which in turn phosphorylates RACK1 at Thr50. RACK1 phosphorylation at Thr50 enhances its interaction with IRF3/7 and thereby limits IRF3/7 phosphorylation. Thus, our results confirm that myeloid RACK1 promotes in vivo viral infection and provide insight into the control of type 1 IFN production in response to virus infection.
Epidural analgesia versus intravenous analgesia after minimally invasive repair of pectus excavatum in pediatric patients: a systematic review and meta-analysis
Authors: Heo Min Hee , Kim Ji Yeon , Kim Jung Hyeon , Kim Kyung Woo , Lee Sang Il , Kim Kyung-Tae , Park Jang Su , Choe Won Joo , Kim Jun Hyun
Published: August 2021

Background: Postoperative pain control after the minimally invasive repair of pectus excavatum (MIRPE) is essential, but there is a controversy about a better analgesic method between epidural and intravenous (IV) analgesia. This systematic review and meta-analysis aimed to compare the effect of epidural versus IV analgesia following MIRPE. Methods: We searched PubMed, MEDLINE, EMBASE, Cochrane Central Register, and ClinicalTrials.gov for randomized controlled trials (RCTs) dated up to 31st May 2021. The primary outcome was the area under the curve (AUC) of the weighted mean visual analog scale (VAS) after MIRPE. The secondary outcomes were postoperative nausea, operation time, total operating room time, and postoperative length of hospital stay.Results: Four RCTs involving 243 patients were finally included in this meta-analysis. The AUC of the weighted mean VAS was 343.62 in the epidural group and 375.24 in the IV group. The epidural group showed lower VAS than the IV group at 12 to 48 h after the surgery. Postoperative nausea, operation time and length of hospital stay was not different between two groups. The epidural group had a significantly longer total operating room time due to epidural catheter insertion time.Conclusions: Epidural analgesia after the MIRPE had a better analgesic effect than IV analgesia. However, IV analgesia may also be a viable option, and physicians should wisely choose analgesic modalities after MIRPE.
A study of cerebrovascular risk factors in depressive patients in old age
Authors: Bhalothia Pyare Lal , Singh Paramjeet , Mawlia Banwari Lal , Singh Sahiba , Jain Priyank
Published: August 2021

Context:

Depression in late life is more likely to be associated with multiple medical comorbidities and cognitive impairment. In old-age hypertension, hyperlipidemia and obesity have been associated with cognitive impairment and vascular depression. The severity of vascular burden has a positive correlation with the severity of depression.

Aims:

This study aimed to find the association between cerebrovascular risk factors (CVRFs) and depression in old age.

Methodology:

A cross-sectional observational study was carried out at the outpatient department (OPD) of psychiatric center, SMS Medical College and Hospital, Jaipur. The patients from the OPD who provided informed consent were the participants in this study. Two hundred cases of depressive episode or recurrent depressive episode (unipolar depression) were included in the study. The diagnosis was made as per the International Classification of Diseases-10 criteria by two psychiatrists independently. Framingham CVRF prediction tool was applied to assess vascular burden. This was followed by statistical analysis.

Results:

The mean age of participants were 68.53 years, the mean score of Hamilton Depression Rating Scale (HAM-D) was 19.10 and the mean score of CVRFs was 13.13. HAM-D score positively correlates with CVRFs score (r = 0.188 and P = 0.008).

Conclusions:

Our study contributes to the growing literature elucidating the relationship of CVRFs in depressed older adults confirming that greater vascular burden can contribute to the severity of depression in geriatric depression.
Cubulating one-relator products with torsion
Authors: Stucky Ben
Published: August 2021

We generalize results of Lauer and Wise to show that a one-relator product of locally indicable groups whose defining relator has exponent at least 4 admits a proper and cocompact action on a CAT(0) cube complex if the factors do.
Finite Element Method Based Evaluation of Bogie Bolster Design
Authors: Pokkula Rakesh , Gupta T.V.K.
Published: August 2021

The requirement of increased turn around time and higher pay-load carrying capacity, weight reduction of components and systems is having much attention in railway industry. The present paper discusses about the Finite Element Analysis (FEA) carried out using ANSYS workbench on the modified design of a bolster in light weight freight bogies. The reduction in weight transforms into higher performance leading to lower power consumption. With this present study, although the modified bolster has not undergone any significant weight reduction, but the modifications in design has lead to increase in stiffeness and reduction in stresses generated for various loading conditions. Presently, bolsters fitted with wagons in Indian Railways are in operational for 20.32t to 22.9t axle load capacities for a variety of applications. The existing and modified bolsters are analysed in static conditions for different loads which includes a vertical load on centre plate, transverse loading and side bearing loading and a comparison has been made. The results on the modified bolster has shown 11% higher bending stiffness in vertical direction at the centre and 9% higher stiffness in tranverse direction as compared to the existing bolster.
Effect of Fuel Weight Distribution on the Aeroelastic Instability of Swept Wings
Authors: Halim Abdul Karim Abd , Ali Jaffar Syed Mohamed , Sulaeman Erwin
Published: August 2021

In this work, a study has been conducted to observe the influence of fuel weight distribution on the flutter characteristics of a high aspect ratio swept wing. In this paper, B777-200 wing model having a 34º sweptback angle is used as a baseline and two other models with the swept angles of 0º (straight wing) and 30º (forward swept) are considered in this study. Aeroelastic analysis is performed ranging from sea level up to 35,000 ft and the influence of in-flight fuel management in several flight altitudes is also investigated. There are four different fuel distribution model are investigated and it was found that some fuel distribution configuration are more critical which may lead to flutter. Moreover it was found that the flight altitude significantly affects the aeroelastic instability.
Gas Tungsten Arc Welding of Stainless Steel 304 and 202 Grades for Optimum Weld Bead Width and Hardness Value
Authors: Mishra Debashis , Mangesh L.
Published: August 2021

Gas tungsten arc welding of two different stainless steel grades of 304 and 202 of 3 mm thickness is attempted through this experimentation to produce the weld joint without any weld defects. The pure argon is supplied to protect the molten weld pool from any form of contaminations. The welding factors like weld current and travel speed are chosen to prepare the welded joints. The response surface central composite experimental design is used to draw 10 numbers of welding conditions. The gas tungsten arc welded butt joint is produced in a single pass manually for complete penetration. The ranges of weld current are chosen as 86, 90, 100, 110, and 114amps. The welding speed is set as 1.54, 2.05, 4.64, 5.09, and 7.5mm/min. The welded sheets are evaluated for weld bead width which is measured with the help of a Vernier caliper. The hardness of the welded joints is also measured. The chosen factors and measured width of the weld bead and hardness value of the weld joints are analyzed by the use of different statistical terms such as R square, ANOVA analysis, lack of fit, t-test, F-test, and effect tests to state a regression expression at 95% assurance level. It is thus understood from the regression analysis that the welding current and travel speed having major influences upon the weld bead width and hardness of the welded joints. In the manual welding technique, both factors are supposed to be carefully matched by the welder otherwise the penetration depth and proper formation of weld bead width are quite difficult to obtain which further increases the total heat input leading to the degradation of mechanical properties. The current experiment is performed to get an optimum condition by optimizing the weld current and speed to get a well-formed weld bead structure by controlling the total heat input. Thus the experiment will be useful to get the desired quality gas tungsten arc welded joints which are most essential in particular for aerospace and automotive industries for various structural applications.
Effect of Tin Oxide Coatings by Spray Pyrolysis Process on Mechanical Properties of Aluminium, Brass and Mild Steel
Authors: Shunmugasundaram M. , Praveenkumar A. , Sankar L. Ponraj , Sivasankar S.
Published: August 2021

Mechanical properties of materials are enhanced by different methods to increase the usage of the materials. In this research spray pyrolysis method is employed to increase the mechanical characteristics of three different materials. The tin oxide is chosen as coated material and aluminium, brass, mild steel are selected as substrate materials. The 500nm thin film is developed over the substrate materials by spray pyrolysis. The substrate temperature are chosen as 300? C for aluminium, 400? C for brass and mildsteel. Nozzle to substrate distance is 0.4 m, substrate temperature is 300? C for aluminium and 400? C for solution concentration as 0.2 mole and solution flow rate is 1ml/min are selected for constant deposition parameters. The hardness and tensile strength result clearly shows that strength is increased by adding the coating over the surface. The material is heated above crystallization temperature and SnO2 increases the tensile and hardness strength of the materials. The triangular metrological microscope is used to examine the microstructure of non coated and coated substrate materials. The microstructural analysis is showed that the uncoated surface of the substrate material is full of rough and pores. And displays that the tin oxide coated surface of the substrates after the initial deposition disclosed a surface with a agglomeration of tin oxide in homogeneous and uniform than the uncoated substrates.
Optimisation Studies for an Efficient Aerodynamic Configuration of a Blended Wing Unmanned Aerial Vehicle
Authors: Padmanabhan M.K. , Santhoshkumar G. , Narayan Praveen , Jeevaraj N. , Dinesh M. , Vignesh S. , Rajesh S.
Published: August 2021

There are various configurations and parameters that contribute to the Design of Unmanned Aerial Vehicles for specific applications. This paper deals with an innovative design of an unmanned aerial vehicle for a specified class of UAVs that require demands such as long endurance, minimized landing space with vertical take-off and landing (VTOL) capabilities. The focal point of this design is superimposing the high endurance blended wing design into tri-copter to address these parameters. The preliminary calculations are initially performed for the blended wing VTOL vehicle based on the required payload capacity and endurance. Superimposing the tri-copter will decrease the aerodynamic efficiency of the vehicle. Computational fluid dynamics (CFD) is a branch of fluid mechanics that uses numerical methods and algorithms to solve complex problems involving fluid flow which will effectively employed to reduce the cost and time during the conceptual and preliminary design stages. CFD analysis was carried out to estimate the major parameters like lift, drag, lift coefficient (CL) and drag coefficient (CD) for various Angle of Attack (AoA) for configurations of blended wing vehicle with and without tri-copter system in the cruise condition. Thus, the vehicle design and propulsion system is effectively optimized using this drag estimation.
Experimental Analysis of Swirl Fuel Injector in Liquid Propellant Rocket Engine
Authors: Dineshkumar G. , Gowrishankar D. , Abdul Bari A.R. , Reddy Maruthi , Sivanesan Dhanushan
Published: August 2021

Fuel injector for a liquid rocket is a very important component since a small difference in its design can drastically affect the combustion efficiency. The primary function of the injector is to break the fuel up into very small droplets. The concept of this project is to perform the fuel atomization with the desired cone angle. This atomization is achieved by passing the fuel through a swirl fuel injector which is connected to the fuel tank and air compressor. Three different orifices of various diameters are designed with different cone angles. The experimental setup consists of a fuel injector with the swirler inside, which is made up of brass with two different vane angles. The air compressor is used for pressurizing the fuel through the injectors. The cold flow experiment is conducted by passing the mixture of air and fuel to get the atomization. The injector is tested with various pressures ranging from 3 to 7 bar for the two cone angles with varying orifice diameters and the different spray patterns are captured. The results are compared, tabulated and correlated with existing values.
Experimental Investigation of Aluminium Hybrid Composites Reinforced with ZnS, TiO2 and BaTiO3 Produced Through Powder Metallurgy
Authors: Rajeshkannan S. , Manikandan I. , Vigneshkumar M.
Published: August 2021

Semiconductors like ZnS, TiO2 and BaTiO3 were reinforced with Al-Al2O3 Metal Matrix Composites (MMCs) and were made through powder metallurgy in order to have high strength, high hardness and good thermal conductivity compared with conventional materials. Three MMC of test specimens were prepared with varying reinforcement ratio Al-Al2O3-ZnS(94-5-1), Al-Al2O3-TiO2(94-5-1), Al-Al2O3-BaTiO3(94-5-1) percentage by weight respectively. The hardness test has been made by using Brinell hardness testing instrument. Hardness test revealed that the addition of reinforcement TiO2, BaTiO3 increases the hardness value. However, the addition of ZnS to the Al-Al2O3 MMCs showed decrease in the hardness value. The crystal structure of the 3 composites were examined through X-Ray Diffraction (XRD) peaks.
Hardware Implementation of Two Stage Interleaved Boost Converter for Electric Vehicle Application
Authors: Suresh S. , Zahira R.
Published: August 2021

This paper deals with the design and simulation of two stage interleaved boost converter (IBC) for electric vehicle (EV) applications. The IBC is considered as a better solution among the different DC-DC topologies for EV for reducing the current ripple, power loss and the size of the components. Traditional DC-DC boost converter (BC) is not applicable for high power applications. Use of interleaving technique minimizes the voltage stress on the switching devices and to be improving the converter performance. Simulation is carried out using MATLAB/Simulink software. The prototype of two stage IBC is fabricated to test the performance. Hardware results shows that the inductor power loss is minimum at a switching frequency of 5 kHz compared to that of 10 kHz. The output power at the load end is maximum for 5 kHz switching when compared with 10 kHz switching. The study shows that the operation of IBC at 5 kHz improves the performance.
Evaluation of clinical, etiological and antimicrobial resistance profile of pediatric urinary tract infections in a secondary health care centre
Authors: Celep Gökce , Burak Özçelik Hüseyin
Published: August 2021

Background: Urinary tract infections are common during childhood. The etiologic agents and empirical antibiotics may vary due to age and geographic area.

Objectives: This study was designed to investigate the urinary tract infection pathogens, their antibiotic resistance profile and risk factors in a sample of well-child population.

Materials and Methods: This retrospective study was conducted in the pediatric clinics of a secondary health-care centre in a one-year period. The source of data was hospital and laboratory records. Toilet trained children and adolescents aged between 5-17 years old with positive urine culture were enrolled into the study. Microbiological studies were conducted ac- cording to international guidelines.

Results: During the study 3640 urine samples were analyzed and 342(9.4%) had significant growth. Gram negative en- terobacteria were the most common infectious agents. Antibiotic susceptibility tests showed low cephalosporine resistance unless ESBL was positive. Multi drug resistance was remarkable. Extended beta lactamase resistance rate was 17%. Previous history of antibiotic use before the present administration was the only significant risk factor for ESBL positivity.

Conclusion: Treating urinary tract infections may become an emerging problem soon. Unless there are risk factors, cepha- losporines are good options, but if so nitrofurantoin or carbapanems should be preferred for treatment in this population.

Keywords: Urinary tract infections; antibiotics; susceptibility.
Rational and design of SATRACD study: detecting subclinical anthracycline therapy related cardiac dysfunction in low income country
Authors: Zhang Wanzhu , Azibani Feriel , Okello Emmy , Kayima James , Walusansa Victoria , Orem Jackson , Sliwa Karen
Published: August 2021

Background: Anthracycline therapy-related cardiac dysfunction (ATRCD) is the most notorious adverse side-effect of chemotherapy. It has become a significant cardiovascular health concern for long-term cancer survivors. With the emerging concept of subclinical ATRCD and newer diagnostictools (Speckle Tracking Echocardiography (STE) and biomarkers), detecting anthracycline cardiac toxicity at an early stage has become an important step to prevent severe cardiac dysfunction and improve the cardiovascular outcome in cancer survivors. Despite the increasing population at risk in sub-Saharan Africa (SSA), there is no contemporary data in Uganda to address the burden, pathogenesis and risk factors of subclinical ATRCD. This big gap in knowledge has led to a lack of local guidelines for monitoring and management of ATRCD.

Methods: SATRACD (Detecting Subclinical Anthracycline Therapy Related Cardiac Dysfunction In Low Income Country) study is an observational prospective cohort study. Three hundred and fifty-three anthracycline naïve cancer patients will be recruited at baseline. Patients are followed up on completion of anthracycline-based chemotherapy and at 6 months after completion of anthracycline therapy. Data on demographics, cancer profile and clinical presentation will be collected at baseline. Comprehensive cardiac assessment will be performed at each visit, including electrocardiogram, conventional echo- cardiography, STE, cardiac and oxidative stress markers. We will be able to determine the incidence of subclinical and clinical ATRCD at 6 months after completion of anthracycline therapy, determine whether hypertension is a major risk factor for ATRCD, evaluate the role of conventional echocardiography parameters, and biomarkers for detecting subclinical ATRCD.

Conclusion: This SATRACD study will provide contemporary data on Ugandan cancer patients who have subclinical and clinical ATRCD, help in the development of local strategies to prevent and manage ATRCD, and improve cardiovascular outcome for Ugandan cancer survivors.

Keywords: SATRACD study; subclinical anthracycline therapy; cardiac dysfunction; low income country.
Transient bone marrow hypoplasia preceding T-Cell acute lymphoblastic leukemia: a case report
Authors: Naturinda Ernest , George Paul , Ssenyondwa Joseph , Bakulumpagi Deogratias , Lubega Joseph , Wasswa Peter
Published: August 2021

Background: Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy and is characterised by hy- perproliferation of malignant lymphocytes in the bone marrow. Rarely, ALL may be preceded by a period of pancytopenia and bone marrow hypoplasia which spontaneously recovers. This phenomenon, which has not before been described in T-cell ALL, is referred to as transient bone marrow hypoplasia.

Case presentation: A 5-year-old boy who presented with high-grade fever and generalised lymphadenopathy, was found to have pancytopenia on peripheral blood count and bone marrow hypoplasia. He was observed over a one-month period during which his bone marrow and peripheral blood counts recovered spontaneously. Symptoms recurred after 4 months and he was found to have blast infiltration of the bone marrow and diagnosed with T-cell ALL.

Conclusion: Cases of transient bone marrow hypoplasia or overt aplastic anemia with spontaneous recovery and then followed by B-cell ALL or Acute Myeloid Leukemia have been described previously in the medical literature. This is the first case of transient bone marrow hypoplasia resulting into ALL of T-cell immunophenotype. While marrow hypoplasia preceding ALL remains poorly understood, it suggests an antecedent environmental insult to lymphoid progenitors or a germline abnormality that predisposes to lymphoid dysplasia. This may provide clues to the hitherto unknown pathophysi- ological process and etiological factors that precede the majority of childhood ALL cases. This case enlightens pediatricians about the existence of such rare cases so as to periodically follow up children with pancytopenia and/or bone marrow hy- poplasia for prolonged periods even after apparent recovery.

Keywords: Pancytopenia, hypoplasia; aplastic anemia; T-cell acute lymphoblastic leukemia; case report.
Molecular study of Nucleophosmin 1(NPM1) gene in acute myeloid leukemia in Kurdish population
Authors: Obaid Othman Galawezh , Sadiq Mohammad Nawsherwan , Hameed Saeed Chiman
Published: August 2021

Background: In patients with Acute Myeloid Leukemia (AML) the most frequent acquired molecular abnormalities and important prognostic indicators is nucleophosmin-1 (NPM1) mutations. Our study aims was molecular study of Nucleop- hosmin -1 gene in Acute Myeloid Leukemia in Kurdish population.

Patients &Methods: A total of 50 patients with AML, (36) of them attended Nanakaly Hospital and (14) attended Hiwa Hospital and 30 healthy subjects as control were selected randomly, all were matched of age and gender. Polymerase chain reaction (PCR) was used for detection of NPM1 gene mutation. Three samples of PCR product for NPM1 gene mutations were sequenced, and mutations were determined by comparison with the normal NPM1 sequence NCBI (GenBank acces- sion number NM_002520).

Results: Out of 50 patients with AML, 5 (10%) of them were NPM1 gene mutation positive, and 45 (90%) were negative. The mutation were a base substitution (C to A), (G to C), (G to T), transversion mutation in addition of frame shift mutation and all mutated cases were heterozygous and retained a wild type allele.

Conclusion: Identification of NPM1 mutations in AML are important for prognostication, treatment decision and optimi- zation of patient care.

Keywords: Acute myeloid leukemia; Nucleophosmin-1 (NPM-1) gene mutation; PCR.
Circulatory microRNA expression profile for coronary artery calcification in chronic kidney disease patients
Authors: Vijayaraghavan Bhooma , Jeyamohan Sridharan , Padmanabhan Giri , Joseph Velangann Antony , Ramanathan Kumaresan
Published: August 2021

Background & Aim: Coronary artery disease (CAD) is the primary cause of mortality in patients with end stage renal disease (ESRD). MicroRNA profiling is proven as a powerful tool in the diagnosis of any disease at the molecular level. Hence, the present study aimed to profile the microRNA expression for CAD especially coronary artery calcification in CKD patients.

Materials and Methods: Two hundread patients with CKD stages 3 to 5 without dialysis and healthy controls were includ- ed in this study. All two hundred patients underwent 1024 multi sliceardiac computed tomography (CT) scan for calcium scoring. The calcium scoring more than 100 have been included in the study. We performed miRNA microarray analysis from serum samples of seven high calcium scored with CKD patients and one control patients.

Results: Seven patients have observed circulating miRNAs has significantly upregulated and downregulated when compared with control patients. mir21, mir 67, mir 390, mir 56, mir 250, mir 65 and mir 13 were up regulated and mir235, mir256, mir226, mir207, mir255, mir193 were downregulated. There was no significant difference in left ventricle function.

Conclusion: 13 microRNAs play a potential role in coronary artery calcification in CKD patients.

Keywords: CKD; CAD; microRNA; coronary artery calcification.
Nutrition education improves knowledge and BMI-for-age in Ghanaian school-aged children
Authors: A Annan Reginald , Apprey Charles , O Agyemang Godwin , M Tuekpe Diane , Asamoah-Boakye Odeafo , Okonogi Satoru , Yamauchi Taro , Sakurai Takeshi
Published: August 2021

Background: Adequate nutrition is required for growth and development in children. This study tested the effectiveness of nutrition education on knowledge and BMI-for-age (BFA) of school-aged children in the Kumasi Metropolis.

Methods: Children, aged 9-13 years old were recruited from ten randomly selected primary schools in the Metropolis. The schools were randomly allocated into 3 groups: nutrition education (3 schools), physical activity (PA) education (3 schools), both interventions (2 schools), or control (2 schools). Following a baseline nutrition and PA knowledge and status assess- ment in 433 children, twice-monthly nutrition and PA education and demonstrations were carried out for 6 months, followed by a post-intervention assessment.

Results: PA and nutrition knowledge improved in all groups (P<0.001); the highest improvement was among those who received both interventions (31.0%), followed by the nutrition education group (29.8%), and the least, the control group (19.1%). Overall, BFA improved by +0.36, from baseline (-0.26) to end of the intervention (+0.10, P<0.001). Within the groups, the nutrition group (+0.65, P<.001) had the highest improvement, then, both the intervention group (+0.27, P<0.001), the PA group (+0.23, P<0.001) and lastly, the control group (+0.18, P=0.001).

Conclusion: Nutrition education could improve knowledge and BMI-for-age in school-aged children in Ghana.

Keywords: School-aged children; nutrition education; BMI-for-age; nutrition knowledge; basic school.
Clinical description and mutational profile of a Moroccan series of patients with Rubinstein Taybi syndrome
Authors: Chafai Elalaoui Siham , Smaili Wiam , Van-Gils Julien , Fergelot Patricia , Ratbi Ilham , Tajir Mariam , Arveiler Benoit , Lacombe Didier , Sefiani Abdelaziz
Published: August 2021

Background: Rubinstein-Taybi syndrome (RSTS; OMIM 180849) is a rare autosomal dominant developmental disorder with an estimated prevalence of one case per 125,000 live births. RSTS is characterized by typical face, broad thumbs and halluces, short stature, and intellectual disability. Facial dysmorphy is characteristic with microcephaly, low frontal hairline, arched eyebrows, long eyelashes, convex profile of nose, narrow palate, and micrognathia. RSTS is mainly due to mutations or microdeletions of the CREBBP gene (about 60%) and more rarely of the EP300 gene (8%).

Objective: Clinical description and identification of mutations of patients with Rubinstein Taybi syndrome.

Methods: PCR and direct sequencing of CREBBP gene.

Results: We report here, the clinical and molecular data of a series of six Moroccan patients with a phenotype of RSTS. The molecular study of the major gene CREBBP (by Sanger Sequencing followed by CGH array, if sequence normal) revealed point mutations in five patients. For the sixth patient, CGH array revealed a microdeletion carrying the CREBBP gene. Through this work, we emphasize the importance of clinical expertise in the diagnosis, management and genetic counseling in Rubinstein Taybi syndrome.

Keywords: Rubinstein Taybi syndrome; CREBBP gene; mutation; Moroccan.
Brucellosis and its associated risk factors to humans and domestic ruminants in Kagera Ecosystem, Tanzania
Authors: Bosco Ntirandekura Jean , Eliaimringi Matemba Lucas , Iddi Kimera Sharadhuli , Bwayla Muma John , Daniel Karimuribo Esron
Published: August 2021

Background: Brucellosis is an important disease for both veterinary and public health. A study was conducted to under- stand the seroprevalence of brucellosis and its associated risk factors in pastoral areas of Kagera, Tanzania. Methods: Sera from 156 patients with malaria-like symptoms were analyzed using the commercial rapid agglutination test (specific for B.abortus and B.melitensis detection) and Fluorescence Polarization Assay (FPA). Sera from 426 cattle, 206 goats and 197 sheep were analyzed using Rose Bengal Plate (RBPT) and Competitive ELISA (c-ELISA) tests. Results: In humans, overall brucellosis, B. abortus, and B. melitensis sero-prevalences were 7.7% (95%CI: 3.8-12.2%), 1.9% (95% CI: 0.4-4.5%), and 5.8 % (95%CI: 2.6-10.6%), respectively. At animal level, seropositivity was 5.9% (95%CI: 4.0-8.6%), 2.5% (95%CI: 0.8-5.7%) and 0.5% (95%CI: 0.01-2.8%) in cattle, goats and sheep, respectively. At herd level, seropositivity was 18.2% (95%CI: 12.0-25.8%) in cattle and 6.9% (95%CI: 2.2-15.3%) in small ruminants. Brucellosis was associated with assisting in parturition without wearing protective gears (OR= 5.6; p= 0.02) in humans, herds of 50-200 animals (OR= 4.2, p= 0.01) and cattle (OR=3.5; p=0.01). The knowledge of brucellosis among pastoralists (OR=0.1; p<0.01) was a protective factor. Conclusion: Brucella infections could be occurring in pastoralists and domestic ruminants in Kagera. Community health education is necessary for the control of brucellosis in Tanzania.

Keywords: Brucellosis; pastoralists; risk factors; Tanzania.