The Effectiveness of Science Teachers’ Use of Scientific Inquiry in Distance Learning During the Spread of the COVID-19 Pandemic in Jordanian Public Schools

The advent of the coronavirus pandemic has disrupted several sectors including education, in general, and Science education. Consequently, we have had to look for creative alternatives and solutions compatible with our educational ambitions and objectives guaranteeing the continuity and efficacy of science education. This study aimed to investigate the efficacy of science teachers’ utilization of scientific inquiry in distance learning under the novel coronavirus pandemic in Jordan-based public schools. Adopting the quantitative approach, the researchers of this study used a questionnaire comprehending (30) consistent items, pre-checked for validity and reliability, subdivided into four themes: Significance of Scientific Inquiry, Extent of Cross-lesson Inquiry Instruction, Challenges of Inquiry Instruction, and Inquiry Improvability in Distance Science Education. The study population comprised a simple random sample of (500) participating men and women teachers from the Northern Educational District under the Ministry of Education in Jordan during the second semester of 2020/2021. Study data were analyzed using SPSS. According to study findings, the efficacy of science teachers’ utilization of scientific inquiry in distance learning under the novel coronavirus pandemic in Jordan-based public schools was rated as moderate averaging (3.36). Besides, study findings showed that there was a high level of agreement on the challenges encountered by science teachers upon science inquiry instruction and that Science teachers’ points of view differed relative to the variables of gender (for males) and teaching experience (for the under-5 years of experience category of men and women Science teachers). Nonetheless, there were no statistically significant differences amongst teachers relative to the educational qualification variable. The study recommended that Science teachers ought to utilize scientific inquiry in science instruction and that similar studies ought to be conducted for other subjects such as Math

The adoption of bitcoins technology: The difference between perceived future expectation and intention to use bitcoins: Does social influence matter?

Bitcoin is a decentralized system that tries to become a solution to the shortcomings of fiat and gold-based currencies. Considering its newness, the adoption level of bitcoin is yet understood. Hence, several variables are proposed in this work in examining user perceptions regarding performance expectancy, effort expectancy, trust, adoption risk, decentralization and social influence interplay, with the context of user’s future expectation and behavioral intentions to use bitcoins. Data were gathered from 293 completed questionnaire and analised using AMOS 18. The outcomes prove the sound predictability of the proposed model regarding user’s future expectations and intentions toward bitcoins. All hypotheses were supported, they were significantly affecting the dependent variables. Social influence was found as the highest predictor of behavioral intention to negatively utilize bitcoins. The significant impact of social influence, adoption risk and effort expectancy which affect behavioral intention to use bitcoins the most, are demonstrated in this study. Bitcoins should thus, present an effective, feasible and personalized program which will assist efficient usage among users. Additionally, the impacts of social influence, adoption risk and perceived trust on behavioral intention to utilize new technology were compared, and their direct path was tested together, for the first time in this context

Spatial Modulation or Spatial Multiplexing for mmWave Communications?

In this paper, two large scale (LS)–multiple–input multiple–output (MIMO) systems and their performance over 3D statistical outdoor millimeter wave (mmWave) channel model are considered and thoroughly analyzed. Namely, spatial multiplexing (SMX) and spatial modulation (SM) systems are considered. The performance of both systems in terms of average bit error ratio (ABER) and channel capacity are derived and studied. Obtained results divulge that SM can achieve higher theoretical capacity than SMX system. Further, SMX system is shown to offer better ABER and mutual information performance as compared to SM system for the same system configuration. Yet, SM demonstrate significant energy efficiency (EE) enhancement for large scale number of transmit antennas.© 2019 Springer. ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering.fi=vertaisarvioitu|en=peerReviewed

Taxifolin prevents cisplatin nephrotoxicity by modulating Nrf2/HO-1 pathway and mitigating oxidative stress and inflammation in mice

Cisplatin (CIS) is an effective chemotherapeutic agent used in the treatment of several malignancies. The clinical use of CIS is associated with adverse effects, including acute kidney injury (AKI). Oxidative stress and inflammation are key events in the development of CIS-induced AKI. This study investigated the protective effect of taxifolin (TAX), a bioactive flavonoid with promising health-promoting properties, on CIS-induced nephrotoxicity in mice. TAX was orally given to mice for 10 days and a single dose of CIS was injected at day 7. Serum blood urea nitrogen (BUN) and creatinine were elevated, and multiple histopathological alterations were observed in the kidney of CIS-administered mice. CIS increased renal malondialdehyde (MDA), nitric oxide (NO), nuclear factor-kappaB (NF-κB) p65, tumor necrosis factor (TNF)-α, and interleukin (IL)-1β, and decreased cellular antioxidants in mice. TAX remarkably prevented kidney injury, ameliorated serum BUN and creatinine, and renal MDA, NO, NF-κB p65, and pro-inflammatory cytokines, and boosted antioxidant defenses in CIS-administered mice. TAX downregulated Bax and caspase-3, and upregulated Bcl-2. These effects were associated with upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) expression and heme oxygenase (HO)-1 activity in CIS-administered mice. In conclusion, TAX prevented CIS-induced AKI by mitigating tissue injury, oxidative stress, inflammation, and cell death. The protective efficacy of TAX was associated with the upregulation of Nrf2/HO-1 signaling

On the Error Performance of Non-orthogonal Multiple Access Systems

Unlike orthogonal multiple access schemes, non-orthogonal (NOMA) ones have arisen as an appealing solution to meet the requirements of the upcoming era of massive connectivity. In NOMA schemes, users are allowed to restrainedly interfere. Therefore, NOMA's ability to serve a number of users more than the number of available orthogonal channels has attracted tremendous research efforts in its different performance aspects. However, its error rate performance has not been sufficiently addressed yet. The currently available derived bit error rate (BER) formulas are either assuming ordered users based on their instantaneous channel gains or fit for special cases only. In this paper, assuming that the users are ordered in terms of the average channel gain and considering arbitrary number of users and modulation order, the average pairwise error probability (PEP) of downlink NOMA systems under Nakagami-m fading channels is derived. Both detection rules, maximum likelihood and successive interference cancellation, have been considered. The derived average PEP is then used to obtain the asymptotic diversity gain and an upper bound on BER using union bounding technique. Simulation results validate the accuracy of the derived formulas over different setups.Qatar National Research FundScopu

A downlink index-modulation based nonorthogonal multiple access scheme

Massive connectivity and spectral efficiency are among the main defining terms of the future communications era. Therefore, revolutionary technologies are required to keep up with the connectivity and spectrum demands. Non-orthogonal multiple access (NOMA) and Index modulation (IM) techniques have emerged as promising candidates to satisfy the spectral efficiency and capacity demands. In this paper, a novel downlink multiple access scheme, called IM-NOMA, is proposed reaping the advantages of both NOMA and IM. In IM-NOMA, the bit block to be sent to each user is divided into two sub-blocks. While the first sub-block is modulated, the second sub-block determines a subset from the available set of channels to carry the modulated symbol. As in power-domain NOMA, the base station (BS) superimposes the modulated symbols carried by the same frequency carrier after a proper power allocation. In such, spectral efficiency is boosted by the extra bits carried by the indexes of the used carriers and the error performance is improved by spreading the users' signals in power domain as well as diversifying the symbols of each user over multiple channels. An upper bound on the average BER is derived in a closed form expression under maximum likelihood (ML) detection method and Rayleigh fading channel. Simulation results show a significant improvement in the BER of the proposed IM-NOMA as compared to the conventional NOMA scheme.Qatar National Research FundScopu

A Novel Downlink IM-NOMA Scheme

In the next generations of communication systems, resources' scarcity devolves to a more critical point as a consequence of the expected massive number of users to be served. Furthermore, the users' contradicting requirements on quality of service forces the network to behave in a dynamic way in terms of the multiple access orchestration and resource assignment between users. Hence, the linear relation between the number of served users and the required (orthogonal or semi-orthogonal) resources in the orthogonal multiple access (OMA) schemes is no longer sufficient. As promising candidates, Non-orthogonal multiple access (NOMA) schemes and index modulation (IM) techniques are emerging to satisfy the ever-increasing connectivity demands and spectral efficiency. In this article, a novel IM-based NOMA downlink scheme, termed as IM-NOMA, is proposed, where the base station (BS) selects a channel or more to serve each user based on the IM concept and the corresponding power level is allocated based on the NOMA concept. At the users' ends, maximum likelihood and successive interference cancellation (SIC) detection methods are considered and their error rate, outage probability and computational complexity are studied. Simulation results confirm the advantage of the proposed IM-NOMA scheme and that it can outperform the conventional NOMA system.Scopu

Low Complexity Constellation Rotation-based SIC Detection for IM-NOMA Schemes

With the expected explosive growth in the user density in wireless networks, recent works have investigated the integration of index modulation (IM) with multiple access schemes, namely the non-orthogonal multiple access (NOMA) scheme. IM-based NOMA schemes have shown appealing advantages in terms of error performance and power efficiency. However, the advantages come with higher detection complexity as an inherited disadvantage of applying IM. In this paper, we propose a constellation rotation-based approach to reduce the detection complexity of the successive interference cancellation (SIC) algorithm. Specifically, we assume two orthogonal constellations to be utilized for transmission. Hence, the introduced rotated-constellations result in orthogonality in the users' signals space which reduces the inter-user interference domains. Therefore the SIC detection complexity is reduced as well. The proposed approach is shown to have a 50% average reduced complexity as compared to classical SIC. Numerical simulations show a significant improvement in terms of error performance as compared to IM-NOMA scheme.Qatar National Research FundScopu

Performance Analysis of Index Modulation Based Multiple Access under Imperfect Channel Estimation

Future generations of wireless communication systems are expected to serve a large number of users with different quality of service requirements. Given the limited spectrum resources, the current multiple access schemes will not be able to fulfill these requirements. The recently proposed Index Modulation based Multiple Access (IMMA) has shown a significant improvement in the performance of uplink transmission as compared to other conventional multiple access schemes in terms of the achievable bit error rate (BER) and the number of served users. As such, it holds great potential in replacing the current multiple access schemes. In this paper, the performance of the IMMA scheme is analyzed under the assumption of the imperfect channel estimation. The average BER is derived in a closed form expression where the impact of the channel estimation error is included. Analytical results are provided to validate the Monte Carlo simulations where a close match is shown over a pragmatic range of signal-to-noise-ratio.Scopu