bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel mutation in perforin gene causing familial hemophagocytic lymphohistiocytosis type 2 in an Egyptian infant: case report
Authors: Almalky Mohamed , Saleh Safaa H. A. , Baz Eman Gamal , Fakhr Ahmed Elsadek
Published: June 2020

Background

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of pathological immune activation characterized by clinical signs and symptoms of extreme inflammation. It results from the uninhibited proliferation and activation of cells of the macrophage lineage and leads to the production of excess amounts of pro-inflammatory cytokines. The familial form of HLH disease is due to mutations in several genes necessary for natural killer (NK) cell and T cell granule-mediated cytotoxic function. These genes are involved in sorting, trafficking, docking, and fusion of cytotoxic granules containing granzymes A and B and perforin to the cell membrane of the target cell (using the proteins LYST, AP-3 complex, Rab27a, Munc 13–4, Munc 18–2, syntaxin 11). Defect in any of those proteins results in defective cytotoxicity. Consequently, genes included in these steps play valuable roles in the pathogenesis of familial HLH disease including perforin (PRF1) gene in which defect causes familial HLH type 2 (FHL2).

Case presentation

A 2-year-old boy suffered from hepatosplenomegaly and fever. He fulfilled the required criteria for the diagnosis of HLH according to HLH-2004 diagnostic criteria. We screened the patient for the presence of mutations in the coding exons and of PRF1 gene by PCR amplification of genomic DNA followed by direct sequencing of the PCR products. We report a novel homozygous deletion/insertion frameshift mutation in PRF1 gene (M28393: exon 2: c.536delAinsCG p.F178fs). We treated him with HLH 2004 protocol of treatment and showed a remarkable response with resolution of fever and decrement in the size of hepatosplenomegaly.

Conclusions

Our study discovered a novel frameshift mutation in PRF1 gene in an infant with HLH disease, and it is the first report of this type of mutation in Egyptian patients with this disease.
Menstrual Pattern, Reproductive Hormones, and Transabdominal 3D Ultrasound in 317 Adolescent Girls
Authors: Assens Maria , Dyre Liv , Henriksen Louise Scheutz , Brocks Vibeke , Sundberg Karin , Jensen Lisa Neerup , Pedersen Anette Tønnes , Main Katharina M
Published: June 2020

Context

The knowledge of normal variation of reproductive hormones, internal genitalia imaging, and the prevalence of gynecological disorders in adolescent girls is limited.

Objective

The study aimed to describe reproductive parameters in postmenarchal girls from the general population including the frequency of oligomenorrhea, polycystic ovary syndrome, and use of hormonal contraception.

Design

The Copenhagen Mother-Child Cohort is a population-based longitudinal birth cohort of 1210 girls born between 1997 and 2002.

Setting

University hospital.

Participants

A total of 317 girls were included, with a median age of 16.1 years and time since menarche of 2.9 years.

Main Outcome Measure(s)

Tanner stage, height, weight, age at menarche, menstrual cycle length and regularity, ovarian/uterine volume, and number of follicles were recorded. Serum concentrations of FSH, LH, anti-Müllerian hormone (AMH), inhibin B, estradiol, testosterone, SHBG, androstenedione, dehydroepiandrosterone sulfate, 17-OH-progesterone, and IGF-1 were measured.

Results

Twenty girls (6.3%) had oligomenorrhea and differed significantly in serum androgens and AMH, age at and time since menarche from girls with regular cycles. Twenty-seven girls were classified with PCOS (8.5%) and had significantly higher 17-OH-progesterone, estradiol, AMH, LH, and age at menarche than the reference group. Girls on oral contraception had significantly higher serum SHBG concentrations and lower serum concentrations of all hormones except AMH and IGF-1. Ovarian follicles 2 to 29.9 mm correlated positively with serum AMH (P < 0.0001).

Conclusions

Most 16-year-old girls had regular menstrual cycles, normal reproductive hormones, and uterine and ovarian ultrasound. Serum AMH reflected ovarian follicle count and may be a useful biomarker of ovarian reserve.
Trophoblast H2S Maintains Early Pregnancy via Regulating Maternal-Fetal Interface Immune Hemostasis
Authors: Wang Banqin , Xu Tonghui , Li Yan , Wang Wenfu , Lyu Chunzi , Luo Dan , Yang Qiuhong , Ning Nannan , Chen Zi-Jiang , Yan Junhao , Chen Dong-bao , Li Jingxin
Published: June 2020

Context

Dysregulated immune hemostasis occurs in unexplained recurrent spontaneous abortion (URSA). Synthesized by cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE), hydrogen sulfide (H2S) promotes regulatory T-cell differentiation and regulates immune hemostasis; yet, its role in URSA is elusive.

Objective

To determine if H2S plays a role in early pregnancy and if dysregulated H2S signaling results in recurrent spontaneous abortion.

Design

First trimester placenta villi and decidua were collected from normal and URSA pregnancies. Protein expression was examined by immunohistochemistry and immunoblotting. Human trophoblast HTR8/SVneo and JEG3 cells were treated with H2S donors; HTR8/SVneo cells were transfected with CBS ribonucleic acid interference (RNAi) or complementary deoxyribonucleic acid. Cell migration and invasion were determined by transwell assays; trophoblast transcriptomes were determined by RNA sequencing (RNA-seq). Wild-type, CBS-deficient, and CBA/J × DBA/2 mice were treated with CBS and CSE inhibitors or H2S donors to determine the role of H2S in early pregnancy in vivo.

Results

CBS and CSE proteins showed cell-specific expressions, but only CBS decreased in the villous cytotrophoblast in URSA versus normal participants. H2S donors promoted migration and invasion and MMP-2 and VEGF expression in human placenta trophoblast cells that contain SV40 viral deoxyribonucleic acid sequences (HTR8/SVneo) and human placenta trophoblast cells (JEG3 cells), similar to forced CBS expression in HTR8/SVneo cells. The CBS-responsive transcriptomes in HTR8/SVneo cells contained differentially regulated genes (ie, interleukin-1 receptor and prostaglandin-endoperoxide synthase 2) that are associated with nuclear factor-κB-mediated inflammatory response. In vivo, dysregulated CBS/H2S signaling significantly increased embryonic resorption and decidual T-helper 1/T-helper 2 imbalance in mice, which was partially rescued by H2S donors.

Conclusion

CBS/H2S signaling maintains early pregnancy, possibly via regulating maternal-fetal interface immune hemostasis, offering opportunities for H2S-based immunotherapies for URSA.
Effects of Potassium or Sodium Supplementation on Mineral Homeostasis: A Controlled Dietary Intervention Study
Authors: Humalda Jelmer K , Yeung Stanley M H , Geleijnse Johanna M , Gijsbers Lieke , Riphagen Ineke J , Hoorn Ewout J , Rotmans Joris I , Vogt Liffert , Navis Gerjan , Bakker Stephan J L , de Borst Martin H
Published: June 2020

Context

Although dietary potassium and sodium intake may influence calcium-phosphate metabolism and bone health, the effects on bone mineral parameters, including fibroblast growth factor 23 (FGF23), are unclear.

Objective

Here, we investigated the effects of potassium or sodium supplementation on bone mineral parameters.

Design, setting, participants

We performed a post hoc analysis of a dietary controlled randomized, blinded, placebo-controlled crossover trial. Prehypertensive individuals not using antihypertensive medication (n = 36) received capsules containing potassium chloride (3 g/d), sodium chloride (3 g/d), or placebo. Linear mixed-effect models were used to estimate treatment effects.

Results

Potassium supplementation increased plasma phosphate (from 1.10 ± 0.19 to 1.15 ± 0.19 mmol/L, P = 0.004), in line with an increase in tubular maximum of phosphate reabsorption (from 0.93 ± 0.21 to 1.01 ± 0.20 mmol/L, P < 0.001). FGF23 decreased (114.3 [96.8-135.0] to 108.5 [93.5-125.9] RU/mL, P = 0.01), without change in parathyroid hormone and 25-hydroxy vitamin D3. Fractional calcium excretion decreased (from 1.25 ± 0.50 to 1.11 ± 0.46 %, P = 0.03) without change in plasma calcium. Sodium supplementation decreased both plasma phosphate (from 1.10 ± 0.19 to 1.06 ± 0.21 mmol/L, P = 0.03) and FGF23 (from 114.3 [96.8-135.0] to 108.7 [92.3-128.1] RU/mL, P = 0.02). Urinary and fractional calcium excretion increased (from 4.28 ± 1.91 to 5.45 ± 2.51 mmol/24 hours, P < 0.001, and from 1.25 ± 0.50 to 1.44 ± 0.54 %, P = 0.004, respectively).

Conclusions

Potassium supplementation led to a decrease in FGF23, which was accompanied by increase in plasma phosphate and decreased calcium excretion. Sodium supplementation reduced FGF23, but this was accompanied by decrease in phosphate and increase in fractional calcium excretion. Our results indicate distinct effects of potassium and sodium intake on bone mineral parameters, including FGF23.

Clinical Trial Registration number

NCT01575041
Mechanistic Causes of Reduced Cardiorespiratory Fitness in Type 2 Diabetes
Authors: Abushamat Layla A , McClatchey P Mason , Scalzo Rebecca L , Schauer Irene , Huebschmann Amy G , Nadeau Kristen J , Liu Zhenqi , Regensteiner Judith G , Reusch Jane E B
Published: June 2020

Type 2 diabetes (T2D) has been rising in prevalence in the United States and worldwide over the past few decades and contributes to significant morbidity and premature mortality, primarily due to cardiovascular disease (CVD). Cardiorespiratory fitness (CRF) is a modifiable cardiovascular (CV) risk factor in the general population and in people with T2D. Young people and adults with T2D have reduced CRF when compared with their peers without T2D who are similarly active and of similar body mass index. Furthermore, the impairment in CRF conferred by T2D is greater in women than in men. Various factors may contribute to this abnormality in people with T2D, including insulin resistance and mitochondrial, vascular, and cardiac dysfunction. As proof of concept that understanding the mediators of impaired CRF in T2D can inform intervention, we previously demonstrated that an insulin sensitizer improved CRF in adults with T2D. This review focuses on how contributing factors influence CRF and why they may be compromised in T2D. Functional exercise capacity is a measure of interrelated systems biology; as such, the contribution of derangement in each of these factors to T2D-mediated impairment in CRF is complex and varied. Therefore, successful approaches to improve CRF in T2D should be multifaceted and individually designed. The current status of this research and future directions are outlined.
Telomere Length Changes in Children With Cushing Disease: A Pilot Study
Authors: Tatsi Christina , Flippo Chelsi , Faucz Fabio R , Sinaii Ninet , Stratakis Constantine A
Published: June 2020

Context

Changes in telomere length (TL) have been linked to certain diseases. Studies on the effect of cortisol on TL have not led to conclusive results.

Objective

To determine whether TL is affected in pediatric patients with Cushing disease (CD) through an exploratory study.

Design

We studied 10 pediatric patients [mean age: 13.3 (2.6) years, 7 females], diagnosed and treated successfully for CD. TL was measured before and approximately 1 year after treatment. TL was compared with controls adjusting for age, and associations with disease characteristics were assessed.

Results

Adjusting for age, total lymphocyte TL of patients did not differ from controls during active disease (P = 0.13) but was shorter than controls at follow-up (P = 0.031). Total lymphocyte TL during active CD and at follow-up did not correlate with markers of hypercortisolemia. There was strong inverse correlation between TL during active disease and at follow-up with triglyceride levels at active disease (adjusted [Adj] R2 = 0.64; P = 0.02 and Adj R2 = 0.5; P = 0.036, respectively), suggesting that the higher the triglycerides, the shorter the TL in patients with CD. The change of TL between active disease and follow-up was positively correlated with systolic blood pressure (Adj R2 = 0.76; P = 0.006).

Conclusions

In this pilot study, TL is shorter in children with hypercortisolemia, a difference that becomes detectable only after cure of CD. Triglycerides and blood pressure appear to be factors that are associated with TL in these patients. Further studies are required to confirm these results.
Water crisis - beyond the destruction
Authors: Bakas T. , Papadimitriou Ι. , Argyri P.
Published: June 2020

A major issue related to the environment, is namely the lack of water and in general the reduction of clean water supplies over time, mostly in our days due to climate change. Through the projection of scientific data, we want to raise the issue and above all to make people feel the importance of the situation. Then, under the context of awareness raising, we present suggested solutions that we have found to solve this serious problem. We also need to add our own solution for an economical method of water desalination and purification. This will reduce the feeling of water scarcity without however being a definitive solution.
A produção simbólica dos desastres naturais: composições, seleções e recortes
Authors: Marchezini Victor
Published: June 2020

Desastres podem ser compreendidos como processos em que subjaz uma produção simbólica sempre construída por agentes em disputa pelo monopólio da visão oficial. Palavras e imagens são usadas pelos agentes para enunciar o que se constitui como ordem e desordem, para conformar uma dada visão sobre o desastre, definindo uma seleção do tempo real e o que vem a se constituir como a realidade. O objetivo deste artigo é analisar esse processo de produção simbólica do desastre a partir de uma seleção de reportagens e imagens dos saques ocorridos durante as inundações e deslizamentos na região do Vale do Itajaí/SC em novembro de 2008. Palavras-chave: Poder simbólico. Mídia. Desastres.
LiveSankey: Advanced Web Visualization in Data Intelligence Multi Domain Contexts
Authors: Conejero José M. , Preciado Juan Carlos , Prieto Alvaro E. , Rodriguez-Echeverria Roberto , Sánchez-Figueroa Fernando
Published: June 2020

In the last years, the growing volumes and sources of data has made Big Data technologies to become mainstream. In that sense, techniques like Data Visualization are being used more and more to group large amounts of data in order to transform them into useful information. Nevertheless, these techniques are currently included in Business Intelligence approaches to provide companies and public organizations with helpful tools for making decisions based on evidences instead of intuition. The Sankey diagram is an example of those complex visualization tools allowing the user to graphically trace meaningful relationships in large volumes of data. However, this type of diagram is usually static so they must be continuously and manually rebuilt on top of massive multivariable environments whenever decision makers need to evaluate different options and they do not allow to establish conditions over the data shown. This paper presents LiveSankey, an approach to automatically generate dynamic Sankey Diagrams allowing users to filter the data shown. As a result, multiple conditions may be established over the data used and the corresponding diagram can be dynamically rebuilt.
A Human-centric and Environment-aware Testing Framework for Providing Safe and Reliable Cyber-Physical System Services
Authors: Ko In-Young , Baek KyeongDeok , Kwon Jung-Hyun , Lira Hernan , Moon HyeongCheol
Published: June 2020

The functions, capabilities, and effects produced by the application services of cyber physical systems (CPS) are usually consumed by users performing their daily activities in a variety of environmental conditions. Thus, it is critical to ensure that those systems neither interfere with human activities nor harm the users involved. In this paper, we propose a framework for testing and verifying the safety and reliability of CPS services from the perspectives of CPS environments and users. The framework provides an environmentaware testing method by which the efficiency of testing CPS services can be improved by prioritizing CPS environments and by applying machinelearning techniques. The framework also includes a metric by which we can automate the test of the most effective services that deliver effects from physical devices to users. Additionally, the framework provides a computational model that assesses mental workloads to test whether a CPS service can cause cognitive depletion or contention problems for users. We conducted a series of experiments to show the effectiveness of the proposed approaches for ensuring the safety and reliability of CPS application services during the development and operation phases.
A Testability and Observability Framework to Assure Traceability Requirements on System of Systems
Authors: Trujillo Leticia Morales , González Miguel Ángel Olivero , Mayo Francisco José Domínguez , García Julián Alberto García , Risoto Manuel Mejías
Published: June 2020

The advance in the digital world has caused a growth of complexity in innovation. Traditional approaches to innovation, based on reductionism, face greater difficulties. That is why we have witnessed the growth of those known as System of Systems (SoS). There is a wide variety of methodologies and domains of application in the literature to form framed solutions in the context of SoS, but there is no unified consensus for its use and even less when it comes to agile environments of continuous integration and deployment in which traceability requirements are critical. In recent years, the need to have traceability software that continuously records and monitors the trace of the entities that interact with it has become an essential feature. In addition, over the years there has been evidence of errors caused by poor traceability control. Therefore, this document presents an agile framework that aims to guarantee the traceability of a SoS from the early stages. This framework unifies the discovery, development and operations, providing full coverage in the conformation of the solution. Finally, we present a case study as future work, which is based on the application of our framework on smart laboratories for assisted reproduction.
Testing of Goods Controlling Device Based on Satellite Systems
Authors: AKHMEDOV Daulet , YERYOMIN Denis , ZHAXYGULOVA Dinara , KALIYEVA Rimma , AFANASYEV Igor , TOKAREV Nikolay
Published: June 2020

This article is devoted to reviewing the results of testing an electronic security seal. The electronic security seal is one of the main parts of Intelligent Transportation System Transit, intended to control the integrity and movement of cargo section of a carrier vehicle by means of the satellite navigation system, mobile cellular communication system and satellite communication system. The electronic security seal operates as remote, autonomous, outdoor used device, installed on the hinges of the cargo compartment doors. In this regard, the development of the electronic security seals is followed by tests to verify the desired characteristics and sustainability together with the resistance to external influences factors. Technical and operating characteristics of the electronic security seal were checked. Tests of the electronic security seal on resistance to such climatic factors as temperature and humidity were carried out. Tests of the electronic security seal on resistance to mechanical influences (vibration, mechanical shock) were performed.
Trajectory assessment and optimisation in the context of small launcher design
Authors: ONEL Alexandru-Iulian , CHELARU Teodor-Viorel
Published: June 2020

The paper presents a mathematical model that can be used to quickly define a nominal trajectory for the studied small launcher configuration. The tool developed based on the proposed mathematical model can be used separately for trajectory assessments or it can be integrated in a multidisciplinary optimisation algorithm for a preliminary small launcher design, together with the trajectory optimisation for a maximum orbital performance.
Use of Multi-Objective Optimization Technique (Taguchi-GRA Approach) in Dry Hard Turning of Inconel 625
Authors: PADHY Chinmaya , SINGH Pariniti
Published: June 2020

Current developments in manufacturing industries consider developing a suitable optimization technique for achieving improved machining performance. This study investigates the optimum values of machining parameters required namely –cutting speed (v), feed rate (f) and depth-of-cut (d) during dry hard turning of Inconel 625 with the aim of enhancing the productivity by minimizing surface roughness (Ra), cutting force (Fc), whereas maximizing material removal rate(MRR). This kind of multi-response process variable (MRP) problems usually known as multi-objective optimizations (MOOs) are solved with the help of Taguchi- Grey Relational Approach (T-GRA). Thus, here is a study conducted to apply Taguchi and Grey relational analysis to optimize multiple performance characteristics during dry hard turning of Inconel -625. As a result, the attained process variables, viz., cutting speed (60 m/min), feed rate (0.3 mm/rev), depth- of- cut (0.25mm) lead to value of optimum response variables –mean cutting force (340 N), surface roughness (0.998 μm) and material removal rate (0.786 mm3/min). In this setup, PVD coated carbide tool inserts were used for dry hard machining (turning) operation.
Performance estimation of Twin Propeller in Unmanned Aerial Vehicle
Authors: PRASAD G.
Published: June 2020

The article deals with the experimental investigation of the thrust performance of a twin propeller used in a typical Unmanned Aerial Vehicle. The propeller is fabricated and tested using low speed subsonic wind tunnel to study the performance characteristics. The results obtained show better performance compared to conventional propellers. The presence of twin propeller has increased the stall characteristics at low Reynolds number. The results indicate a substantial increase in thrust generation of up to 25 percent. The payload carrying capacity and handling quality will improve using this technique during pandemic to spray disinfectants. The results obtained provide an alternate design for future propellers applications. Further it is observed that the endurance of the Unmanned Aerial Vehicle can be reduced considerably, by few alternate solution.
Meta-heuristic optimization of copper friction stir weldments
Authors: RAJU L. Suvarna , VENU Borigorla
Published: June 2020

This work focused on the optimization of process parameters, which may result in increasing mechanical properties of copper weldments. The different tool pin profiles such as plain taper cylindrical, taper cylindrical with threaded, triangular, square, pentagonal and hexagonal having constant shoulder diameters were used to fabricate the weldments. The experiments were conducted at different levels of tool rotational speed and weld speeds using six different tool pin profiles. The experimental results revealed that the defect free weldments could be obtained by using different tool pin profiles. From the investigation, it was found the weldments made by using a square (SQ) tool pin profile resulted in better mechanical properties compared to other tool pin profiles. Objective functions are developed for the mechanical properties in terms of input parameters. The input parameters of an SQ tool pin profile were optimized using a metaheuristic optimization based algorithm named teaching learning based optimization (TLBO) technique to improve mechanical properties. The TLBO suggests a combination of 900 rpm of tool rotation speed and 40 mm/min weld speed for better properties.
Computational Flow Field Analysis around a Single Wrap-around Fin
Authors: SHARMA Nayhel , NAGI Gurteg Singh , CHAUDHARY Hrishabh , SAINI Palak , KUMAR Rakesh
Published: June 2020

A flow field aerodynamic analysis using Computational Fluid Dynamics (CFD) model of a single wrap around fin is performed at 0° angle of attack and its flow visualizations are presented in this paper for a subsonic to supersonic Mach range. A comparative study is performed by utilizing two WAF geometries aligned in opposite directions and with different edges (Sharpened and Blunt). The aerodynamic characterization has been conducted using a realizable κ-ϵ turbulence model utilizing a high-quality mesh to understand the nuances of the flow around the curved fin structure. The quantities of interest are the computed aerodynamic coefficients which have been validated with their precursors. By investigating the contours of the pressure coefficient and the relative Mach number, the flow phenomenon in the vicinity of the curved fin can be understood in a finer way.
VIGV Angle Optimization for Subsonic Axial Flow Compressor
Authors: SINGH Prabhat , CHAND Dharmahinder Singh
Published: June 2020

Long-term performance of an axial-flow compressor by the scheduling of inlet guide vanes at off-design conditions has been studied in this paper. The compressors are used in various industries and in aviation sectors for different operations at different climatic conditions; due to diverse climatic conditions the compressor is unable to give good performances as expected. At the design conditions, the results show that the variations in total pressure loss coefficient, volume flow rate, pressure ratio, and others like thermodynamics, aerodynamic properties are different at different stagger angles of 15°, 30° and 45°. BladeGen tools were used to design the inlet guide vanes for the investigations. The performance parameters of the axial flow compressor were analyzed by using ANSYS CFX and were validated using the analytical method. The objective of this study is to minimize the total pressure loss coefficient and improve the aerodynamic characteristics of an inlet guide vanes at different stagger angles and hence reduce the overall fuel consumption. The outcomes of this work give an improved insight into the efficient use of a VIGV in axial flow compressor.
The Extension of a Method of Risk Analysis from Aeronautics to Medicine. Application to Endoscopic Surgery
Authors: Corneliu BERBENTE Corneliu BERBENTE , TURBATU Dumitru
Published: June 2020

The 6-4-3-5 method of risk analysis from Aeronautics is adapted and extended to Medicine with emphasis on Endoscopic Surgery. The new main risk factors are identified and the corresponding risk severity is evaluated. In the complete method “6”represents the number of persons in the evaluating team,“4” gives the used weights 1; 2; 3; 4; “3” is the number of variants required to each person from the evaluating team and “5” indicates the time for evaluation (five minutes). The risk is defined as a product between the probability of an event and the event severity, S, taking one of the values 1; 2; 3; 4. The value S = 1 represents the normal case and S = 4 corresponds to the maximum damage, for example, dead people resulting in one aviation accident. Three more simple variants are also given.
Rising Significance of the Air Force in Current Unpredictable Security Environment
Authors: IVANČÍK Radoslav , NEČAS Pavel
Published: June 2020

This paper is a continuation of the ongoing research of authors whose, within the framework of interdisciplinary scientific research, deal with various aspects of ensuring the security and defence of the Slovak Republic and states that are members of the North Atlantic Alliance and the European Union. In their research, the authors point out a deterioration of the global and regional security environment, the growth of symmetrical and asymmetric security threats, the continued deterioration of the security situation in some regions, and negative consequences for the level of security and defence of states and their citizens. In order to contribute to the development of security and military science, the issue of the Air Forces and their extraordinary importance in guaranteeing comprehensive security and defence of the state and simultaneously ensuring collective defence in cooperation with the allies from NATO and EU is addressed and widely elaborated.
The Influence of Geometry on Failure Modes of Countersunk Bolted Hybrid Joints
Authors: COMAN Calin-Dumitru
Published: June 2020

This paper presents a numerical study for the influence of geometry on the damage initiation and growth in the CFRP (Carbon Fiber Reinforced Polymer) laminated plate of the hybrid metal-composite countersunk bolted joints. A detailed 3D finite element model incorporating material and friction-based contact full nonlinearities is developed to investigate the geometry effects on the failure modes of the hybrid metal-composite bolted joints. The material model for CFRP joint counterpart integrates nonlinear shear response for unidirectional laminae, Hashin-type failure criteria and strain-based continuum degradation rules which were developed using the UMAT user subroutine in MSC. Patran-Nastran (MSC. Software Corporation Inc.) commercial software. Experiments were conducted in order to validate the nonlinear progressive damage analysis (PDA) results on the failure modes of the joints with countersunk bolts. The numerical and experimental results showed that the joint geometry parameter defined by the ratio between the plates width and hole diameter has an important influence in designing phase of a reliable bolted joint and its effects on damage initiation and failure modes were quite accurately predicted by the numerical model, which proved to be computational efficient and could predict damage mechanisms in hybrid metal-composite countersunk bolted joints.
Influence of Nozzle Type, Divergence Angle and Area Ratio on Impulse of Pulse Detonation Engine
Authors: DHAMA Sanjeev Kumar , JINDAL T. K. , MANGAL S. K.
Published: June 2020

The influence of nozzle geometry on the impulse produced by the single cycle Pulse detonation engine (PDE) was experimentally investigated. For each experiment the nozzles were attached at the end of the engine. The impulse produced by the pulse detonation engine was calculated from the measured thrust. The thrust measurement was done by sliding the engine on the central bar of the thrust stand. The main structure of the basic PDE has a detonation tube with one terminal closed, a Schelkin spiral used as deflagration to detonation device, and a thrust stand to support the structure. Stoichiometric acetylene and oxygen mixture were used as detonation mixture. Various nozzles with a range of divergent angle and area ratios were tested. The calculations of the impulse were made from the thrust pulse for the duration it lasted. The effect of the type of nozzle, divergent angle and area ratio were observed. The bell shaped nozzle with large angle of divergence produced maximum specific impulse of 80 Sec with 20° divergence angle and area ratio of 6.942; maximum impulse was produced by the bell shaped nozzle with a small area ratio of 2.969 and 10° divergence angle. The maximum total impulse obtained was 1200 N-sec.
Rapeseed oil additivated with hexagonal boron nitride
Authors: IONESCU Traian Florian , SORCARU Adrian-Alin , GUGLEA Dionis , CRISTEA George Catalin , GEORGESCU Constantin , DELEANU Lorena
Published: June 2020

This paper presents the influence of hexagonal boron nitride (hBN) as additive in refined rapeseed oil in different mass concentration of 0.25%wt, 0.5%wt and 1%wt on the tribological parameters, obtained on a four-ball machine. The test parameters were load: 100 N, 200 N and 300 N and the rotational speed 1000 rpm, 1400 rpm and 1800 rpm, corresponding to the following sliding speed, 0.38 m/s, 0.53 m/s and 0.69 m/s, respectively. The average particle size of hBN is 14 nm. For the tested ranges of the parameters, the additivation of rapeseed oil with hBN does not improve the friction coefficient, but the wear rate of WSD seems to be less sensitive for the more severe regimes when the vegetal oil is additivated.
Aerodynamic and Experimental Analysis of Bio-mimic corrugated dragonfly aerofoil
Authors: KHAN Md Akhtar , PADHY Chinmaya
Published: June 2020

In this work, experimental and computational approach is used to understand the corrugation attitude of a bio-inspired dragonfly mimicked corrugated airfoil at low Reynolds number varying from 15000 to 75000 to understand the advantages of pleated corrugated airfoil. The CFD analysis is carried out on the 2-dimensional bio-mimetic corrugated ‘Pantala flavescens’ dragonfly forewing to predict the aerodynamic characteristics of the corrugated dragonfly aerofoil with varying angle of attack from 0° to 8°. The computational analysis of the wing profile is done using the ANSYS-19 ICEM CFD and FLUENT software. For the experimental test, the model is printed in 3-D printer machine and tested in subsonic Wind Tunnel at different speeds and different angle of attacks using a wind tunnel 6-component balance. The computational simulation reveals the exemplary results of the pleated airfoil (corrugated aerofoil) with new design constraints. Finally, the computational result is validated with experimental results.
Seeing through multimode fibers with real-valued intensity transmission matrices
Authors: Zhao Tianrui , Ourselin Sebastien , Vercauteren Tom , Xia Wenfeng
Published: June 2020

Image transmission through multimode optical fibers has been an area of immense interests driven by the demand for miniature endoscopes in biomedicine and higher speed and capacity in telecommunications. Conventionally, a complex-valued transmission matrix is obtained experimentally to link the input and output light fields of a multimode fiber for image retrieval, which complicates the experimental setup and increases the computational complexity. Here, we report a simple and high-speed method for image retrieval based on our demonstration of a pseudo-linearity between the input and output light intensity distributions of multimode fibers. We studied the impact of several key parameters to image retrieval, including image pixel count, fiber core diameter and numerical aperture. We further demonstrated with experiments and numerical simulations that a wide variety of input binary and gray scale images could be faithfully retrieved from the corresponding output speckle patterns. Thus, it promises to be useful for highly miniaturized endoscopy in biomedicine and spatial-mode-division multiplexing in telecommunications.
A crop tree release variant of precommercial thinning using a backpack mounted chain saw
Authors: Soucy Michel , Béland Martin
Published: June 2020

Although crop tree release (CTR) in hardwood stands is an accepted variant of precommercial thinning (PCT), the lack of an affordable and feasible method hinders its adoption. CTR implies selecting between 150 and 500 trees ha when trees are between 7 and 12 m high and cutting only stems competing with the target crop trees. We performed a field trial of a CTR variant of PCT in a 27.8 ha hardwood stand using a backpack mounted chain saw. A detailed time study was performed to document the trial over 13 days. Compared to conventional PCT performed earlier in the life of a stand, precommercial crop tree release required cutting larger stems, which showed to be feasible and productive using a backpack mounted chain saw. Productivity varied between 0.22 to 0.47 ha h during the trial, Although productivity could vary with stand characteristics and worker, this proof of concept trial demonstrates some of the potential uses that this new saw configuration offers and sets the basis for an eventual larger scale deployment of this treatment.â1â1
New Bounds for the Stochastic Knapsack Problem
Authors: Kumar Ekesh
Published: June 2020

The knapsack problem is a problem in combinatorial optimization that seeks to maximize the objective function \(\sum_{i = 1}^{n} v_ix_i\) subject to the constraints \(\sum_{i = 1}^{n} w_ix_i \leq W\) and \(x_i \in \{0, 1\}\), where \(\mathbf{x}, \mathbf{v} \in \mathbb{R}^{n}\) and \(W\) are provided. We consider the stochastic variant of this problem in which \(\mathbf{v}\) remains deterministic, but \(\mathbf{x}\)is an \(n\)-dimensional vector drawn uniformly at random from \([0, 1]^{n}\). We establish a sufficient condition under which the summation-bound condition is almost surely satisfied. Furthermore, we discuss the implications of this result on the deterministic problem.
Trial Interventions in ABCA4- Retinopathy
Authors: Al Breiki Majid
Published: June 2020

Abstract: Inherited retinal diseases collectively are one of the leading causes of visual impairment worldwide. ABCA4 retinopathy is the most common inherited retinal disease. In the last few years, there are many advances in the understanding of this disease, which led to many interventional trials with promising results at the moment. This paper is going to present a brief background up to date knowledge in the context of the disease pathophysiology, the main mechanisms involved in this disease and related diseases, and different approaches of the intervention trials. I will be using a literature review to highlight the main structural, physiological, chemical, functional characteristics of ABCA4 transporter physiology. This will be followed by a brief discussion about pathophysiology. Next, analysing, extracting and comparing different interventional options and presenting the current clinical trials for each will be done. This paper expected to discusses and rationally compare between different treatment trials approaches their advantages over others and challenges. A sensible, possible application from current trials from different diseases with similar pathogenesis and possible research opportunities will be discussed.
‘El PISA preescolar’: Un nuevo paradigma para la evaluación de los alumnos y alumnas de educación infantil
Authors: Sofou Efstratia , Jiménez Ramírez Magdalena
Published: June 2020

EEste artículo tiene como objetivo revisar, discutir y criticar el Estudio Internacional de Aprendizaje Temprano y Bienestar Infantil (IELS) de la OCDE, como una nueva evaluación internacional estandarizada para la educación infantil, que se vislumbra como un PISA a nivel preescolar. El artículo analiza el discurso dominante de la calidad en educación infantil en las nuevas políticas globales que sugieren lo que es mejor para la infancia y ofrece una revisión del trabajo previo de la OCDE en el campo de la educación infantil. Presentamos las principales críticas sobre el proyecto IELS y sus posibles consecuencias, su impacto en la política y en la práctica educativa. En las conclusiones del artículo destacamos que si bien es necesaria la investigación en el ámbito de la educación infantil para identificar los desafíos pendientes, el IELS no es la mejor manera por cuanto conforma parte de una red mundial de medición en expansión y conlleva el peligro de tratar los hallazgos producidos por método cuantitativos como una representación de la realidad, sin someterla a preguntas e interpretaciones diversas en cada contexto nacional.
A RESSIGNIFICAÇÃO DO RUBÁI EM MICHELINY VERUNSCHK
Authors: Benites de Moraes Paulo Eduardo , Wanderley Milena Karina De Souza
Published: June 2020

A proposta deste trabalho é discutir a ressignificação do rubái na obra Geografia íntima do deserto (2003), de Micheliny Verunschk. Este gênero poético fora consagrado pelo poeta persa Omar Khayám, e em um poema de Micheliny Verunschk nota-se a retomada desta estrutura poética. Busca-se demonstrar que, para além da intertextualidade com o erotismo do poeta persa, a recriação de Verunschk dá ênfase à subjetividade e à intimidade. Neste sentido, ampliam-se os sentidos possíveis de leitura e esta nova ressignificação cria um discurso literário dissonante.Palavras-chave: Subjetividade; tradição; ressignificação; discurso dissonante.
Alternative Splicing Regulation of Anthocyanin Biosynthesis in Camellia sinensis var. assamica Unveiled by PacBio Iso-Seq
Authors: Chen Lijiao , Shi Xingyun , Nian Bo , Duan Shuangmei , Jiang Bin , Wang Xinghua , Lv Caiyou , Zhang Guanghui , Ma Yan , Zhao Ming
Published: June 2020

Although the pathway and transcription factor regulation of anthocyanin biosynthesis in tea plants [Camellia sinensis (L.) O. Ktze] are known, post-transcriptional regulation mechanisms involved in anthocyanin accumulation have not been comprehensively studied. We obtained the full-length transcriptome of a purple cultivar (‘Zijuan’) and a normal green cultivar (‘Yunkang 10#) of C. sinensis var. asssamica (Masters) showing different accumulation of anthocyanins and catechins through PacBio isoform sequencing (Iso-Seq). In total, 577,557 mapped full-length cDNAs were obtained, and 2,600 average-length gene isoforms were identified in both cultivars. After gene annotations and pathway predictions, we found that 98 key genes in anthocyanin biosynthesis pathways could have undergone alternative splicing (AS) events, and identified a total of 238 isoforms involved in anthocyanin biosynthesis. We verified expression of the C4H, CHS, FLS, CCOM, F3′5’H, LAR, PAL, CCR, CYP73A13, UDP75L12, UDP78A15/UFGT, UDP94P1, GL3, MYB113, ANR, ANS, F3H, 4CL1, CYP98A3/C3H, CHI, DFR genes and their AS transcripts using qRT-PCR. Correlation analysis of anthocyanin biosynthesis and gene expression results revealed that C4H1, FLS1, PAL2, CCR2, UDP75L122 and MYB113-1 are crucial AS transcripts for regulating anthocyanin biosynthesis in C. sinensis var. assamica. Our results reveal post-transcriptional regulation of anthocyanin biosynthesis in tea plants, and provide more new insights into the regulation of secondary metabolism.
Intervenciones farmacológicas para el tratamiento de la Enfermedad por Coronavirus (COVID-19)
Authors: Huaroto Fabiola , Reyes Nora , Huamán Karen , Bonilla Catherine , Curisinche-Rojas Maricela , Carmona Gloria , Gutierrez Ericson , Caballero Patricia
Published: June 2020

Varios fármacos han sido propuestos como alternativas terapéuticas para COVID-19. Se efectuó una búsqueda sistematica en MEDLINE (vía PubMed) hasta el 20 de marzo de 2020, con el fin de identificar la evidencia disponible sobre intervenciones farmacológicas para tratamiento específico de COVID-19. 947 publicaciones fueron identificadas y 15 estudios seleccionados: 3 ensayos clínicos, 5 series de casos y 7 reportes de casos. La calidad de la evidencia procedente de ensayos clínicos fue evaluada según la metodología GRADE. La evidencia existente para hidroxicloroquina, favipiravir y lopinavir/ritonavir procede de ensayos clínicos que reportan resultados favorables para los dos primeros fármacos en tanto que no se observó ningún beneficio al adicionar lopinavir/ritonavir al tratamiento estándar. Sin embargo, debido a las limitaciones metodológicas, la evidencia es de muy baja certeza para hidroxicloroquina y de baja certeza para favipiravir y lopinavir/ritonavir. Respecto al uso de arbidol interferón, o el uso combinado de estos con lopinavir/ritonavir, la evidencia es limitada ya que deriva de serie de casos o reporte de casos con resultados no determinantes. No se identificaron estudios que permitan determinar la eficacia y seguridad de intervenciones farmacológicas frente a COVID-19.
Esperar a la evidencia antes de tratar a casos leves de COVID-19
Authors: Pecho-Silva Samuel , Navarro-Solsol Ana Claudia , Arteaga-Livias Kovy , Panduro-Correa Vicky
Published: June 2020

Con mucho interés hemos leído el artículo especial recientemente publicado en la revista que usted dirige (1) en el cual los autores sugieren el uso de hidroxicloroquina (HC) o cloroquina (CQ) para el tratamiento de casos leves de Covid-19 en la comunidad. Hemos revisado las 39 referencias que citan los autores sin poder encontrar alguna que se refiera al tratamiento de casos leves de Covid-19. La tabla 1 muestra las referencias citadas que son estudios clínicos con HC o CQ en casos moderados/severos de Covid-19. En la carta de Gao (2) se menciona que 100 pacientes de varios ensayos clínicos vienen recibiendo CQ con éxito; sin embargo, esa información preliminar no puede ser corroborada. En la serie de casos de Gautret (3) el 90% de pacientes tratados con HQ presentaron un aclaramiento viral al final del estudio. Hay un reporte de Chen (4) que está disponible en la web, que no ha sido revisado por pares, ni se conoce la revista que lo ha aceptado.
Drought and the Sacramento–San Joaquin Delta, 2012–2016: Environmental Review and Lessons
Authors: Durand John , Bombardelli Fabian , Fleenor William , Henneberry Yumiko , Herman Jon , Jeffres Carson , Leinfelder-Miles Michelle , Lusardi Robert , Manfree Amber , Medellín-Azura Josué , Milligan Brett , Moyle Peter , Lund Jay
Published: June 2020

This paper reviews environmental management and the use of science in the Sacramento–San Joaquin Delta during California’s 2012–2016 drought. The review is based on available reports and data, and guided by discussions with 27 agency staff, stake-holders, and researchers. Key management actions for the drought are discussed relative to four major drought water management priorities stated by water managers: support public health and safety, control saltwater intrusion, preserve cold water in Shasta Reservoir, and maintain minimum protections for endangered species. Despite some success in streamlining communication through interagency task forces, conflicting management mandates sometimes led to confusion about priorities and actions during the drought (i.e., water delivery, the environment, etc.). This report highlights several lessons and offers suggestions to improve management for future droughts. Recommendations include use of pre-drought warnings, timely drought declarations, improved transparency and useful documentation, better scientific preparation, development of a Delta drought management plan (including preparing for salinity barriers), and improved water accounting. Finally, better environmental outcomes occur when resources are applied to improving habitat and bolstering populations of native species during inter-drought periods, well before stressful conditions occur.
Introduction of Bluefin Killifish (Lucania goodei) into the Sacramento–San Joaquin Delta
Authors: Mahardja Brian , Goodman Andrew , Goodbla Alisha , Schreier Andrea , Johnston Catherine , Fuller Rebecca , Contreras Dave , McMartin Louanne
Published: June 2020

Biological invasion by non-native species has been identified as one of the major threats to native fish communities worldwide. The fish community of San Francisco Estuary is no exception, as the estuary has been recognized as one of the most invaded on the planet and the system has been impacted significantly by these invasions. Here, we summarize the introduction and probable establishment of a new species in the Sacramento–San Joaquin Delta, the Bluefin Killifish (Lucania goodei), as discovered by the US Fish and Wildlife Service Delta Juvenile Fish Monitoring Program (DJFMP). The DJFMP has conducted a large-scale beach seine survey since 1976, and it is the longest-running monitoring program in the San Francisco Estuary that extensively monitors the shallow-water nearshore habitat. Possibly introduced as discarded aquarium fish within the vicinity of the Delta Cross Channel, Bluefin Killifish is a close relative of the Rainwater Killifish (Lucania parva), another non-native fish species that has been present in the San Francisco Estuary system for decades. Studies in their native range suggest that Bluefin Killifish will fill a similar niche to Rainwater Killifish, albeit with a more freshwater distribution. The potential ecological impact of Bluefin Killifish remains unclear in the absence of additional studies. However, we have been able to track the spread of the species within the Sacramento–San Joaquin Delta through the existence of long-term monitoring programs. Our findings demonstrate the value of monitoring across various habitats for the early detection and proactive management of invasive species.