Miracle-dz/UniFAR-FTUs huggingface dataset:
Diamond-based submillimeter backward wave oscillator

Making use of fabrication technology commonly employed in the manufacture of liquid crystal and semiconductor devices, but not previously applied to vacuum devices, the diamond-based backward wave oscillator (BWO) provides a miniature, energy efficient, electronically tunable and mass producible signal source in the sub mm wavelength regime. Fabricated within a shell of chemical vapor deposited (CVD) diamond for mechanical and thermal robustness, the BWO employs a novel biplanar interdigital slow wave circuit, which will be manufactured by utilizing a process developed at Genvac. Conventional silicon fabrication technology is used to form a negative of the desired structure, which serves as a mold for the deposition of the diamond. The diamond structure is then selectively metallized. The structure is formed in two halves and then accurately positioned and bonded using techniques routinely employed in the fabrication of liquid crystal displays. The device has been modeled extensively, and designs of the slow wave circuit, electron gun and collector for operation at 300 and 600 GHz have been completed. Fabrication of the 300 GHz device is in progress. It is estimated to weigh 29 gm, and, for operation over a 10% tuning range, the minimum output power is predicted to be 18 mW.
Analysis of buried gate MESFET under dark and illumination

D.C. analysis has been carried out for a buried-gate GaAs metal semiconductor field effect transistor (MESFET) under dark and front illumination. The photovoltage I-V characteristics and the transconductance of the device have been evaluated. The results indicate very good performance of the device compared to other devices like MESFET under back illumination and MESFET with front illumination having surface gate. Thus, buried-gate optical field effect transistor (OPFET) will be highly suitable for optical communication and optical computing.
Recommendation Systems on E-Learning and Social Learning: A Systematic Review

E-learning is renowned as one of the highly effective modalities of learning. Social learning, in turn, is considered to be of major importance as it promotes collaboration between learners. For properly managing learning resources, recommender systems have been implemented in e-learning to enhance learners' experience. Whilst recommender systems are of widespread concern in online learning, it is still unclear to educators how recommender systems can improve the learning process and have a positive impact on learning. This paper seeks to provide an overview of the recommender systems proposed in e-learning between 2007 and the first part of 2021. Out of 100 initially identified publications for the period between 2007 and the first part of 2021, 51 articles were included for final synthesis, according to specific criteria. The descriptive results show that most of the disciplines involved in educational recommender systems papers have approached e-learning in a general way without putting as much emphasis on social learning, and that recommender systems based on explicit feedbacks and ratings were the most frequently used in empirical studies. The synthesis of results presents several recommender systems types in e-learning: (1) Content-based recommender systems, (2) Collaborative-filtering recommender systems, (3) Hybrid recommender systems and (4) Recommender systems based on supervised and unsupervised algorithms. The conclusions reflect on the almost lack of critical reflection on the importance of addressing recommender systems in social learning and social educational networks in particular, especially as social learning has particular requirements, the weak databases size used in some research work, the importance of acknowledging the strengths and weaknesses of each type of recommender system in an educational context and the need for further exploration of implicit feedbacks more than explicit learners’ feedbacks for more accurate recommendations.
Surround Modulation Properties of Tectal Neurons in Pigeons Characterized by Moving and Flashed Stimuli

Simple Summary Surround modulation is a basic visual attribute of sensory neurons in many species and has been extensively characterized in mammal primary visual cortex, lateral geniculate nucleus, and superior colliculus. Little attention has been paid to birds, which have a highly developed visual system. We undertook a systematic analysis on surround modulation properties of tectal neurons in pigeons (Columba livia). This study complements existing studies on surrounding modulation properties in non-mammalian species and deepens the understanding of mechanisms of figure–background segmentation performed by avians. Abstract Surround modulation has been abundantly studied in several mammalian brain areas, including the primary visual cortex, lateral geniculate nucleus, and superior colliculus (SC), but systematic analysis is lacking in the avian optic tectum (OT, homologous to mammal SC). Here, multi-units were recorded from pigeon (Columba livia) OT, and responses to different sizes of moving, flashed squares, and bars were compared. The statistical results showed that most tectal neurons presented suppressed responses to larger stimuli in both moving and flashed paradigms, and suppression induced by flashed squares was comparable with moving ones when the stimuli center crossed the near classical receptive field (CRF) center, which corresponded to the full surrounding condition. Correspondingly, the suppression grew weaker when the stimuli center moved across the CRF border, equivalent to partially surrounding conditions. Similarly, suppression induced by full surrounding flashed squares was more intense than by partially surrounding flashed bars. These results suggest that inhibitions performed on tectal neurons appear to be full surrounding rather than locally lateral. This study enriches the understanding of surround modulation properties of avian tectum neurons and provides possible hypotheses about the arrangement of inhibitions from other nuclei, both of which are important for clarifying the mechanism of target detection against clutter background performed by avians.
Deep Learning in Retinal Image Segmentation and Feature Extraction: A Review

Image recognition and understanding is considered as a remarkable subfield of Artificial Intelligence (AI). In practice, retinal image data have high dimensionality leading to enormous size data. As the morphological retinal image datasets can be analyzed in an expansive and non-invasive way, AI more precisely Deep Learning (DL) methods are facilitating in developing intelligent retinal image analysis tools. The most recently developed DL technique, Convolutional Neural Network (CNN) showed remarkable efficiency in identifying, localizing, and quantifying the complex and hierarchical image features that are responsible for severe cardiovascular diseases. Different deep layered CNN architectures such as LeeNet, AlexNet, and ResNet have been developed exploiting CNN morphology. This wide variety of CNN structures can iteratively learn complex data structures of different datasets through supervised or unsupervised learning and perform exquisite analysis for feature recognition independently to diagnose threatening cardiovascular diseases. In modern ophthalmic practice, DL based automated methods are being used in retinopathy screening, grading, identifying, and quantifying the pathological features to employ further therapeutic approaches and offering a wide potentiality to get rid of ophthalmic system complexity. In this review, the recent advances of DL technologies in retinal image segmentation and feature extraction are extensively discussed. To accomplish this study the pertinent materials were extracted from different publicly available databases and online sources deploying the relevant keywords that includes retinal imaging, artificial intelligence, deep learning and retinal database. For the associated publications the reference lists of selected articles were further investigated.
A New Method for Designing Modified Compact Microstrip LPF with Sharp Roll-Off and Wide Stopband

A new method for designing a compact microstrip lowpass filter (LPF) with wide stopband width (SBW) and sharp roll off (ROF) is presented. In the proposed designing procedure, high impedance microstrip lines are bent to achieve an LPF with compact size. Then, to compensate for the effect of bending microstrip lines, the lengths of the lines are mathematically modified. Moreover, adding a suppressing cell composed of a radial stub resonator and a butterfly stub resonator increases the SBW. Also, an elliptic filter structure is used to obtain sharp ROF. In this work, an LPF with 1.12 GHz cutoff frequency, 0.147 λg  0.133 λg filter size; where λg is the guided wavelength at cutoff frequency, the SBW equal to 13.4 GHz, and the ROF more than 201 dB / GHz, is designed, simulated and fabricated to demonstrate efficiency of the proposed method. Also, the other conventional characteristics for the fabricated LPF such as 0.3 dB insertion loss, 14.4 dB return loss, and suppression factor equal to 2.2, are in the appropriate range of their amounts.
FedVoting: A Cross-Silo Boosting Tree Construction Method for Privacy-Preserving Long-Term Human Mobility Prediction

The prediction of human mobility can facilitate resolving many kinds of urban problems, such as reducing traffic congestion, and promote commercial activities, such as targeted advertising. However, the requisite personal GPS data face privacy issues. Related organizations can only collect limited data and they experience difficulties in sharing them. These data are in “isolated islands” and cannot collectively contribute to improving the performance of applications. Thus, the method of federated learning (FL) can be adopted, in which multiple entities collaborate to train a collective model with their raw data stored locally and, therefore, not exchanged or transferred. However, to predict long-term human mobility, the performance and practicality would be impaired if only some models were simply combined with FL, due to the irregularity and complexity of long-term mobility data. Therefore, we explored the optimized construction method based on the high-efficient gradient-boosting decision tree (GBDT) model with FL and propose the novel federated voting (FedVoting) mechanism, which aggregates the ensemble of differential privacy (DP)-protected GBDTs by the multiple training, cross-validation and voting processes to generate the optimal model and can achieve both good performance and privacy protection. The experiments show the great accuracy in long-term predictions of special event attendance and point-of-interest visits. Compared with training the model independently for each silo (organization) and state-of-art baselines, the FedVoting method achieves a significant accuracy improvement, almost comparable to the centralized training, at a negligible expense of privacy exposure.
The Processivity of Telomerase: Insights from Kinetic Simulations and Analyses

Telomerases are moderately processive reverse transcriptases that use an integral RNA template to extend the 3′ end of linear chromosomes. Processivity values, defined as the probability of extension rather than dissociation, range from about 0.7 to 0.99 at each step. Consequently, an average of tens to hundreds of nucleotides are incorporated before the single-stranded sDNA product dissociates. The RNA template includes a six nucleotide repeat, which must be reset in the active site via a series of translocation steps. Nucleotide addition associated with a translocation event shows a lower processivity (repeat addition processivity, RAP) than that at other positions (nucleotide addition processivity, NAP), giving rise to a characteristic strong band every 6th position when the product DNA is analyzed by gel electrophoresis. Here, we simulate basic reaction mechanisms and analyze the product concentrations using several standard procedures to show how the latter can give rise to systematic errors in the processivity estimate. Complete kinetic analysis of the time course of DNA product concentrations following a chase with excess unlabeled DNA primer (i.e., a pulse-chase experiment) provides the most rigorous approach. This analysis reveals that the higher product concentrations associated with RAP arise from a stalling of nucleotide incorporation reaction during translocation rather than an increased rate constant for the dissociation of DNA from the telomerase.
SIMULTANEOUS SELECTION FOR HIGH YIELDING AND STABILITY OF SOME ECONOMIC KENAF CHARACTERS

The materials used for the present study consisted of fourteen kenaf genotypes (G) which were evaluated over six environments (three at Ismailia Governorate, two at Giza Governorate and one at El-Beheira Governorate) through three successive seasons (2009 to 2011). in Egypt. The analysis of variance revealed highly significant differences among genotypes, environments and G x E interaction for all studied traits, indicating a wide range of variation among genotypes, environments and these genotypes exhibited differential response to environmental conditions. The significant variance due to residual for all characters indicated that genotypes differed with respect to their stability suggesting that prediction would be difficult, which means that mean performance alone would not be appropriate. Interaction component of variance (σ 2 ge) was less than the genotypic variance (σ 2 g) for all characters. This means that genotypes differ in their genetic potential for these traits. The observed narrow range between phenotypic and genotypic coefficients of variability with high heritability in broad since for fiber percentage . Also, fiber weight per plant, technical stem length and plant height showed similar results, indicating possibility of using these three yield traits in selection criteria with giving more weight for fiber weight per plant and technical stem length for improving green stalk yield per plant in turn fiber yield. The criterion, yield stability (YS i ) statistic indicated that S.105/2 and S.113 were proved to be superior in yield and stability for all characters studied as well as three genotypes, S.96/20, Giza3 and S.8 were stable for most characters studied. Therefore, the two genotypes (S.105/2 and S.113) maintained mean performance advantage across nearly all the environments sampled by maintaining high level for the above-mentioned traits and they are recommended to be released as commercial stable high yielding cultivars and/or to be incorporated in kenaf breeding program for producing stable high yielding lines. Phenotypic correlation coefficients among green stalk weight with other related characters of kenaf, indicated that, plant height, technical stem length, and fiber percentage are the major components contributing to green stalk weight per plant. Therefore, selection for these traits will improve green stalk weight per plant and in turn fiber yield in kenaf.
Adaptability in Wireless Sensor Networks Through Cross-Layer Protocols and Architectures

Complex applications and increased sensor capabilities will help proliferate wireless sensor networks into everyday life. However, as sensor nodes are battery-operated, sensor networks will require protocols to spare every possible bit of energy. This can be accomplished through cross-layer protocol optimizations that specialize the protocols for specific application requirements. However, as researchers continue to contribute to the field of sensor networks, protocols will evolve, and more efficient work will replace older ideas. Therefore, flexibility and eased maintenance of the network will be required to make sensor networks feasible for new deployments and customers. Thus there are competing goals of energy-efficiency, achieved by specialization through cross-layer protocol design, and flexibility, achieved through modularity in a layered protocol design. My thesis shows that these competing goals can be balanced by the use of crosslayer information exchange that enables the protocols (and hence the network) to adapt to current application and network conditions. Adapting the protocols via cross-layer information exchange allows the network to make best use of the limited energy resources of the sensor nodes while maintaining required application quality of service and retaining a flexible protocol stack. In support of this thesis, we have (1) performed a case-study comparing cross-layer designs with a layered design, (2) designed and evaluated an architecture that enables the sharing of information across traditional stack boundaries, (3) proposed a solution to manage the bidirectional flow of information between middleware and the protocol stack, (4) demonstrated the advantage of allowing a sensor network middleware to exploit this cross-layer information to maximize the time when application quality of service is met, and (5) developed various techniques at the MAC layer to take advantage of the availability of this cross-layer information to extend node lifetime. With the standardization of cross-layer information exchange
Researching women and men 1996–2020: Is androcentrism still dominant?

Abstract This article assesses the balance of research concerning women and men over the past quarter century using the crude heuristic of counting Scopus-indexed journal articles relating to women or men, as suggested by their titles or abstracts. A manual checking procedure together with a word-based heuristic was used to identify whether an article related to women or men. The heuristic includes explicit mentions of women and men, implicit mentions, and a set of gender-focused health issues and medical terminology. Based on the results, more published articles now relate to women than to men. Moreover, more than twice as many articles relate exclusively to women than exclusively to men, with the ratio increasing from 2.16 to 1 in 1996 to 2.25 to 1 in 2020. Monogender articles mostly addressed primarily female health issues (maternity, breast cancer, cervical cancer) with fewer about primarily male health issues (testicular cancer, pancreatic cancer, health needs of men who have sex with men). Some articles also explicitly addressed gender inequality, such as empowering female entrepreneurs. The findings suggest that the androcentrism of early science has eroded in terms of research topics. This apparent progress should be encouraging for women researchers and society.
Use of ferric chloride contained in the rejects from the steel industry as a coagulant for the fuel washing wastewater treatment

The aim of the present study firstly the treatment of the fuel washing wastewater by a coagulation–flocculation process, using ferric chloride (FeCl3), and secondly the comparison between a commercial FeCl3 (40%) and an industrial effluent rich in FeCl3 (30%) coagulant, in terms of the coast and the pollution reduction efficiency. For these purposes, the fuel washing wastewater was subjected to a coagulation–flocculation treatment using different doses of both coagulants. The obtained results showed that the commercial coagulant exhibited better pollution removal efficiency compared to the one contained in the industrial effluent. Indeed, the commercial coagulant FeCl3 (40%) was capable to remove 92%, 96% and 88% of chemical oxygen demand (COD), nitrate and phenol, respectively, using 120 mg/L of FeCl3 (40%). Moreover, 98% and 61% of turbidity and ammonium ions, respectively, using 160 mg/L of FeCl3 (40%). While, the FeCl3 (30%) contained in the industrial effluent allowed the elimination of 98%, 67%, 56%, 91% and 82% of turbidity, COD, ammonium, nitrate and phenol, respectively. These high removal efficiencies were attained by using 90 mg/L of FeCl3 (30%). The overall data showed that the industrial effluent rich in FeCl3 can be reused due to its significant elimination efficiency and low cost for the treatment of fuel-washing wastewater.
Receiver System: Lessons Learned From Solar Two

The Boeing Company fabricated the Solar Two receiver as a subcontractor for the Solar Two project. The receiver absorbed sunlight reflected from the heliostat field. A molten-nitrate-salt heat transfer fluid was pumped from a storage tank at grade level, heated from 290 to 565 C by the receiver mounted on top of a tower, then flowed back down into another storage tank. To make electricity, the hot salt was pumped through a steam generator to produce steam that powered a conventional Rankine steam turbine/generator. This evaluation identifies the most significant Solar Two receiver system lessons learned from the Mechanical Design, Instrumentation and Control, Panel Fabrication, Site Construction, Receiver System Operation, and Management from the perspective of the receiver designer/manufacturer. The lessons learned on the receiver system described here consist of two parts: the Problem and one or more identified Solutions. The appendix summarizes an inspection of the advanced receiver panel developed by Boeing that was installed and operated in the Solar Two receiver.
Utilization of Cellulose to Its Full Potential: A Review on Cellulose Dissolution, Regeneration, and Applications

As the most abundant natural polymer, cellulose is a prime candidate for the preparation of both sustainable and economically viable polymeric products hitherto predominantly produced from oil-based synthetic polymers. However, the utilization of cellulose to its full potential is constrained by its recalcitrance to chemical processing. Both fundamental and applied aspects of cellulose dissolution remain active areas of research and include mechanistic studies on solvent–cellulose interactions, the development of novel solvents and/or solvent systems, the optimization of dissolution conditions, and the preparation of various cellulose-based materials. In this review, we build on existing knowledge on cellulose dissolution, including the structural characteristics of the polymer that are important for dissolution (molecular weight, crystallinity, and effect of hydrophobic interactions), and evaluate widely used non-derivatizing solvents (sodium hydroxide (NaOH)-based systems, N,N-dimethylacetamide (DMAc)/lithium chloride (LiCl), N-methylmorpholine-N-oxide (NMMO), and ionic liquids). We also cover the subsequent regeneration of cellulose solutions from these solvents into various architectures (fibers, films, membranes, beads, aerogels, and hydrogels) and review uses of these materials in specific applications, such as biomedical, sorption, and energy uses.
Plastic waste

Plastic pollution is an urgent global problem that threatens the entire ecosystem, causing climate change and many other consequences that humans have to bear. Therefore, citizens need to uphold their sense of responsibility, consciously change living habits, say no to single-use plastic products. Protecting the environment, limiting plastic waste is protecting ourselves.