Miracle-dz/UniFAR-FTUs huggingface dataset:
Optimal Estimation of the Roughness Coefficient and Friction Factor of a Pipeline

This work addresses the estimation of two interrelated parameters of the fluid flow in pipes. First, a numerical and experimental evaluation of some proposed methods to compute the friction factor in turbulent regime is presented. Special attention is given to an explicit solution obtained through the Lambert W-function. Subsequently, a method to estimate the roughness coefficient using nonlinear optimization techniques is proposed, which then allows determining the friction factor from it. Numerical tests were performed for a wide range of operating points of a pipeline. In order to validate the proposed approach, experimental analysis was carried out on a pipeline pilot-plant. The results show the applicability and effectiveness of the proposed method.
Crystal structure of 3,3′-(E)-diazene-1,2-diylbis{4-[(3,4-dinitro-1H-pyrazol-1-yl)-NNO-azoxy]-1,2,5-oxadiazole}

The crystal structure of a novel high-energy density material 3,3′-(E)diazene-1,2-diylbis{4-[(3,4-dinitro-1H-pyrazol-1-yl)-NNO-azoxy]-1,2,5-oxadiazole} (C10H2N18O12) was determined and refined using laboratory powder diffraction data. The title compound crystallizes in space group P21/c with a = 9.5089(3) Å, b = 11.6331(4) Å, c = 10.6270(3) Å, β = 116.2370(12), V = 1054.43(6) Å3. The asymmetric unit contains half of the molecule. The molecular conformation contains a weak intramolecular hydrogen bond C–H⋯O–N, both nitro groups are disordered, and the structure is dominated by weak O⋯π and O⋯O contacts.
The Protective Effects of Melatonin on the Monocrotophos and Quinalphos Induced Oxidative DNA Damage in Rats

Organophosphate pesticides are widely used in agriculture and household for pest control and consequently have been a major cause of toxicity in farmers and others especially in India. The present study was carried out to evaluate the ability of two pesticides: monocrotophos (MCP) and quinalphos (QNP) to generate oxidative stress and to explore the possible protective effects of melatonin in combating the caused stress. The purpose of the study was to find a suitable agent which could reduce the toxic symptoms generated due to acute as well as chronic exposure of monocrotophos and quinalphos. We studied the potential of MCP and QNP to generate oxidative stress and subsequent oxidative damage to DNA in the rat tissues and lymphocytes. Oxidative stress was measured by quantitating the levels of reactive oxygen species (ROS), total antioxidant capacity, accumulation of lipid peroxidation end products while DNA oxidation was measured by the modified comet assay using the bacterial repair enzymes, formamidopyrimidine glycosylase (Fpg) and endonuclease III (Endo III) in the liver, brain and lymphocytes of rats given for two days and subchronic exposure of MCP and QNP, both separately and in combination. The results showed that both acute and subchronic pesticide exposure, separately and in combination, lead to the generation of oxidative stress. Extensive oxidative damage of both purine and pyrimidine bases was observed in liver, brain and lymphocytes of rats given exposure with MCP or QNP, separately or in combination. MCP was found to be more toxic than QNP as highest DNA damage was observed in this group of rats. The combined exposure of MCP and QNP does not potentiate each other’s action. However, co-treatment of melatonin, a well established antioxidant, decreased the oxidative stress and damage caused to the DNA.
A novel vehicle tracking and speed estimation with varying UAV altitude and video resolution

ABSTRACT In this paper, a novel vehicle tracking and speed estimation method based on aerial videos is developed. The main objective of this research is to investigate how depth features of a vehicle extracted from aerial videos by a wide residual network could be used to realize accurate tracking for estimating the speed of the vehicle. The salient characteristics of the proposed method are: (1) Traffic analysis and robust vehicle detection are possible by virtue of the use of deep neural networks. (2) Employing the state-of-the-art object detector, namely the You Only Look Once (YOLO) network, a tracking-by-detection method is then designed to detect and track vehicles. (3) The error rate of data association is reduced by associating the tracking process with a vehicle re-identification algorithm whereby the motion features are combined with depth features of the vehicle. (4) Considering the varying Unmanned Aerial Vehicle (UAV) altitude and video resolution, a novel exponential mapping model of the vehicle speed from the pixel space to the real world is presented. The accuracy of speed estimation is effectively improved by employing the least squares algorithm to fit the measurement data. Simulation results and comparative studies with the state-of-the-art methods demonstrate superior performance of the proposed approach for vehicle tracking and speed estimation.
Avatar-Mediated Communication in Social VR: An In-depth Exploration of Older Adult Interaction in an Emerging Communication Platform

While HCI researchers have begun designing personalised VR experiences for older adults, there has been limited research examining the use of social VR - where users interact via avatars in a virtual environment. Avatar-mediated communication (AMC) is a crucial component of the social VR experience, but older users’ experience with AMC is poorly understood. We conducted a five-month study with 16 older adults evaluating a co-designed social VR prototype. Results show that AMC in social VR was seen as medium that supported introverted users to express themselves and was viewed as offering advantages when discussing sensitive topics. Our study provides new insights into how older adults view AMC in social VR as a communication medium and we contribute six design reflections, based on our results, that highlight the steps that can be taken to ensure that AMC in social VR can meet the communication needs of older users.
Synthesis And Characterization of N-((6-methylpyridin-2-yl)carbamothioyl)thiophene-2-carboxamide and Its Co(II), Ni(II) and Cu(II) Complexes: Calculation of Molecular Orbitals, Antioxidant and Antitumor Activities

N-((6-methylpyridin-2-yl)carbamothioyl)thiophene-2-carboxamide, C 12 H 11 N 3 OS 2 (HL)and its Co(II), Ni(II) and Cu(II) complexes (ML 2 type) have been synthesized and characterized by elemental analysis, FT-IR , 1 H-NMR and HR-MS methods. In addition, HL was characterized by single crystal X-ray difraction method. The HL crystallizes in the monoclinic crystal system with P 1 2 1 / c 1 space group, Z =4, a=7.2326(8) A, b=18.3492(16) A, c=9.7724(9) A. The [ML 2 ] complex structures were optimized using B97D/TZVP level. Molecular orbitals of HL ligand was calculated at the same level. Antioxidant activity of the complexes were measured by using the DPPH and ABTS assays. Anticancer activity of the complex were studied MTT assay in MCF-7 breast cancer cells.
[The "protein-machine" concept and its consequences].

: Analysis is presented of the concept "protein-machine" and implying consequences, both of theoretical and experimental character. The approach "protein-machine" is compared with other approaches--"coherent excitation", "molecular dynamics" and "limited diffusion". In terms of the approach "protein-machine" valuable information inserted in the biological macromolecule and determining its functions is taken into account. It reflects the biological specificity and at the same time removes mystic shadow from this concept.
Map Merging with Suppositional Box for Multi-Robot Indoor Mapping

For the map building of unknown indoor environment, compared with single robot, multi-robot collaborative mapping has higher efficiency. Map merging is one of the fundamental problems in multi-robot collaborative mapping. However, in the process of grid map merging, image processing methods such as feature matching, as a basic method, are challenged by low feature matching rate. Driven by this challenge, a novel map merging method based on suppositional box that is constructed by right-angled points and vertical lines is proposed. The paper firstly extracts right-angled points of suppositional box selected from the vertical point which is the intersection of the vertical line. Secondly, based on the common edge characteristics between the right-angled points, suppositional box in the map is constructed. Then the transformation matrix is obtained according to the matching pair of suppositional boxes. Finally, for matching errors based on the length of pairs, Kalman filter is used to optimize the transformation matrix. Experimental results show that this method can effectively merge map in different scenes and the successful matching rate is greater than that of other features.
Preparation of a New Granular Acid-Activated Neutralized Red Mud and Evaluation of Its Performance for Phosphate Adsorption

A new granular acid-activated neutralized red mud (AaN-RM) was successfully prepared with powdered AaN-RM, powdered straw, and hydroxypropyl methylcellulose (HPMC) for effective phosphate adsorption. The maximum phosphate adsorption capacity of granular AaN-RM reached 86.69 mg/g, which was much higher than that previously reported. Its excellent phosphate adsorption capacity was mainly attributed to high specific surface area caused by complex mineralogy of iron and aluminum and addition of powdered straw. The mass ratio of different ingredients, sintering temperature, and time affected the characteristics of granular AaN-RM greatly. When the mass ratio of powdered straw increased from zero to 33%, the total pore volume of granular AaN-RM increased from 0.0056 to 0.0375 cm3/g; however, the effective chemical compositions reduced when the addition of powdered straw was too high. With increasing the sintering temperature and time, the polymerizability of granular AaN-RM was significantly improved, but a too.
ESR studies of kerogen conversion in shale pyrolysis

We have used Electron Spin Resonance (ESR) observations of the carbon radicals occurring in thermally treated shale samples to trace the transformation of shale kerogen. The objective of the work is to provide some feeling for the sequence of transformations which occur within the organic matrix during thermal treatment. We observe significant increases in the carbon radical density with more severe thermal treatments, accompanied by a fall in the magnitude of the g-value and linewidth of the radicals. These results reflect progressive carbon radical generation during thermal transformations.
On pre-emptive vehicle stability control

Future vehicle localisation technologies enable major enhancements of vehicle dynamics control. This study proposes a novel vehicle stability control paradigm, based on pre-emptive control that considers the curvature profile of the expected path ahead in the computation of the reference direct yaw moment and braking control action. The additional information allows pre-emptive trail braking control, which slows down the vehicle if the predicted speed profile based on the current torque demand is deemed incompatible with the reference trajectory ahead. Nonlinear model predictive control is used to implement the approach, in which also the steering angle and reference yaw rate provided to the internal model are varied along the prediction horizon, to account for the expected vehicle path. Two pre-emptive stability control configurations with different levels of complexity are proposed and compared with the passive vehicle, and two state-of-the-art nonlinear model predictive stability controllers, one with and one without non-pre-emptive trail braking control. The performance is assessed along obstacle avoidance tests, simulated with a high-fidelity model of an electric vehicle with in-wheel motors. Results show that the pre-emptive controllers achieve higher maximum entry speeds – up to ∼34% and ∼60% in high and low tyre-road friction conditions – than the formulations without preview.
No‐reference quality assessment of dynamic sports videos based on a spatiotemporal motion model

This paper proposes an approach to improve the performance of no‐reference video quality assessment for sports videos with dynamic motion scenes using an efficient spatiotemporal model. In the proposed method, we divide the video sequences into video blocks and apply a 3D shearlet transform that can efficiently extract primary spatiotemporal features to capture dynamic natural motion scene statistics from the incoming video blocks. The concatenation of a deep residual bidirectional gated recurrent neural network and logistic regression is used to learn the spatiotemporal correlation more robustly and predict the perceptual quality score. In addition, conditional video block‐wise constraints are incorporated into the objective function to improve quality estimation performance for the entire video. The experimental results show that the proposed method extracts spatiotemporal motion information more effectively and predicts the video quality with higher accuracy than the conventional no‐reference video quality assessment methods.
Electrochemical investigation of 2-[8-hydroxyquinoline-5-yl)azo]benzo[$c$]cinnoline on a platinum electrode in dimethysulfoxide

2-[8-hydroxyquinoline-5-yl)azo]benzo[c]cinnoline was synthesized for the first time and shown to possess electrochromic characteristic, i.e. changing color during the forward and back electrolysis at --1.35 V and 0.00 V, respectively, in DMSO medium. Therefore, the electrochemical investigation of this compound appears to be worthwhile. The electrochemical reduction of 2-[8-hydroxyquinoline-5-yl)azo]benzo[c]cinnoline was investigated by cyclic voltammetry, controlled potential electrolysis, and chronoamperometry techniques in the presence of 0.10 mol L$^{-1}$ tetrabutylammonium tetrafluoroborate in dimethyl sulfoxide at platinum electrode. 2-[8-Hydroxyquinoline-5-yl)azo]benzo[c] cinnoline displays three sharp cathodic peaks and three anodic peaks in the cyclic voltammogram. The diffusion coefficients and the number of electrons transferred were calculated by using an ultramicroelectrode and platinum electrode. The number of transferred electrons was found to be one for each peak. The standard heterogeneous rate constant for reduction was calculated by the Klingler--Kochi technique. The electrochemical reduction mechanism of 2-[8-hydroxyquinoline-5-yl)azo]benzo[c]cinnoline was also investigated by using various electrochemical techniques, such as bulk electrolysis, and spectroscopic methods, like electron spin resonance spectroscopy. Bulk electrolysis results also provided evidence for each peak belonging to reduction of one electron, two of which were confirmed by electron spin resonance spectroscopy. This new chemical is found to be an electrochromic substance.
Discordance of the Repeat GeneXpert MTB/RIF Test for Rifampicin Resistance Detection Among Patients Initiating MDR-TB Treatment in Uganda

Abstract Background The Global Laboratory Initiative (GLI) guidelines recommend repeat for GeneXpertMTB/RIF (XpertMTB/RIF) in patients with a low pretest probability of rifampicin resistance (RR). Methods This was a cross-sectional study using results of sputum specimens collected from participants screened for the STREAM 2 trial. We recruited all patients with XpertMTB/RIF RR-TB detected who were referred for RR/multidrug-resistant (MDR) TB treatment initiation at Mulago National Referral Hospital, Kampala, between September 2017 and October 2019. At baseline, smear microscopy, repeat XpertMTB/RIF, Xpert Ultra, and MTBDRplus assays were done on sputum specimens. Culture-based drug susceptibility testing (DST) was performed on discordant specimens. We analyzed the prevalence and factors associated with discordance between initial and repeat XpertMTB/RIF RR and false XpertMTB/RIF RR. False XpertMTB/RIF RR was defined as no RR detected by any of Xpert Ultra, LPA, or culture DST (reference comparator). Results A total of 126/130 patients had repeat XpertMTB/RIF results, of whom 97 (77.0%) had M. tuberculosis detected, 81 (83.5%) had RR detected, and 1 (1.0%) had RR indeterminate. The prevalence of discordant XpertMTB/RIF RR was 15/96 (15.6%), whereas false XpertMTB/RIF RR prevalence was 10/96 (10.4%). Low–bacillary load sputum specimens were more likely to have discordant XpertMTB/RIF RR and false XpertMTB/RIF RR results (adjusted odds ratio [aOR], 0.04; 95% CI, 0.00–0.37; P = .01; aOR, 0.02; 95% CI, 0.01–0.35; P = .01, respectively). Conclusions Our findings show a high false-positive rifampicin resistance rate in low–TB burden patients, which calls for repeat testing in order to prevent unnecessary prescription of anti-MDR-TB therapy.
Partial characterization of Prunus Necrotic Ringspot Virus on apple in EGYPT 

A severe isolate of Prunus necrotic ringspot virus (PNRSV) was isolated from apple orchards in the vicinity of Nubaria city, Beheira governorate, Egypt. Infected-apple trees showed chlorotic, necrotic ringspots, and shoot holes on leaves. Severely infected- trees withered, became useless, and were removed causing severe economic losses. Reverse transcriptase (RT) polymerase chain reaction (PCR), RT-PCR, using degenerate primer pair for the coat protein (CP) gene of Ilarvirus amplified products similar to those produced from peach and apricot isolates of PNRSV-infecting stone fruits). Dot blotting immuno-binding assay (DBIA showed a positive reaction between PNRSV-infected apple sap and an Egyptian antiserum for PNRSV. Purified preparation from infected leaves, using the electro-elution technique yielded nucleoprotein, which had Amax and Amin at 260 and 240 nm respectively. Electron microscopy examination showed spherical virions with ca. 26 nm in diameter.
Non-destructive assessment of pigments in apple fruit and carrot by laser-induced fluorescence spectroscopy (LIFS) measured at different time-gate positions

Laser-induced fluorescence spectroscopy (LIFS) was non-destructively applied to apple fruit and carrot for determining changes in fruit and vegetable pigment contents. These changes were provoked by storing the products at low (0°C for carrots, 4°C for apples) or room (20°C) temperature. The samples were excited by short laser pulses emitting at 337 nm, and recordings of fluorescence spectra were carried out directly on the tissue surface and in fruit extracts in a wavelength range from 350 to 820 nm. Because of the different life-times of the excited state of the molecules of interest, spectra were taken with time-resolved readings to enable/allow separating overlaid fluorescence signals. The polyphenol content of apples was measured using high-performance liquid chromatography.It was found that changes in fluorescence intensity in the blue-green wavelength range can be attributed to variations in fruit polyphenol content. PLS calibration models were built and resulted in high correlation coefficients between LIFS data and polyphenol contents in apples, e.g. R=0.99 for caffeic acid. Furthermore, chlorophyll degradation during storage became visible in the red fluorescence of apple fruit. Furthermore, stored carrots showed increasing fluorescence intensities changes in the blue wavelength area. This might be due to diminishing quenching and reabsorption effects of the decreasing content of carotenoids, which are non-fluorescent molecules. These results show the potential use of LIFS for the rapid and non-destructively assessment of fruit and vegetable pigments such as carotenoids, chlorophylls and polyphenols which are considered as indicators to monitor the product quality along the entire supply chain.
EPA: The effective pipeline architecture for CNN accelerator with high performance and computing efficiency based on FPGA

Thanks to the great developments of the latest Field Programmable Gate Array (FPGA), the performance bottleneck of Deep Learning hardware accelerators has been converted to computing ability. In this paper, a novel FPGA‐based Convolutional Neural Network (CNN) Accelerator architecture, named the Effective Pipeline Architecture (EPA) is proposed to optimize the resource usage for the implementation of the CNN calculation. As the unique storage strategies, which contain many creative designing details, are adopted and optimized for different CNN models and layers, great DSP computing efficiency can be achieved in the fine‐grained pipeline. Moreover, compared with the traditional architectures, through the kernel combination and data scheduling, twice throughput for the general matrix multiplication is realized in a great many parallel DSP48E resources. As a result, the realization of Yolov2‐Tiny achieves 873 Giga Operations Per Second (GOPS) by 902 DSPs with 67 Frames Per Second (FPS), and the computing efficiency in most layers can even reach more than 90%, which improves the calculation performance and efficiency comparing with the previous designs, and is significant to meet the increasing computing requirement.
Quaternization reaction of some N, N-dimethylalkylamines with benzyl chloride

The parameters which influence the quatemization reaction of some N,N-dimethylalkylamines of RN(CH 3 ) 2 , type (R = octyl, decyl, dodecyl, tetradecyl and hexadecyl) with benzyl chloride were studied. By thermogravimetric analyses, the kinetic parameters, the reaction order, "n", and the activation energy, "Ea", of the thermal decomposition of the quaternary salts prepared in this study, were established.
Metaheuristic to Optimize Computational Convergence in Convection-Diffusion and Driven-Cavity Problems

This work presents an optimization proposal to better the computational convergence time in convection-diffusion and driven-cavity problems by applying a simulated annealing (SA) metaheuristic, obtaining optimal values in relaxation factors (RF) that optimize the problem convergence during its numerical execution. These relaxation factors are tested in numerical models to accelerate their computational convergence in a shorter time. The experimental results show that the relaxation factors obtained by the SA algorithm improve the computational time of the problem convergence regardless of user experience in the initial low-quality RF proposal.
Machine learning and automatic selection of attributes for the identification of Chagas disease from clinical and sociodemographic data

Objective: evaluate the potential use of machine learning and the automatic selection of attributes in discrimination of individuals with and without Chagas disease based on clinical and sociodemographic data. Method: After the evaluation of many learning algorithms, they have been chosen and the comparison between neural network Multilayer Perceptron (MLP) and the Linear Regression (LR) was done, seeking which one presents the best performance for prediction of the Chagas disease diagnosis, being used the criteria of sensitivity, specificity, accuracy and area under the ROC curve (AUC). Generated models were also compared, using the methods of automatic selection of attributes: Forward Selection, Backward Elimination and genetic algorithm. Results: The best results were achieved using the genetic algorithm and the MLP presented accuracy of 95.95%, 78.30% sensitivity, and specificity of 75.00% and AUC of 0.861. Conclusion: It was proved to be a very interesting performance, given the nature of the data used for sorting and use in public health, glimpsing its relevance in the medical field, enabling an approximation of prevalence that justifies the actions of active search of individuals Chagas disease patients for treatment and prevention.