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Towards Atomic MIMO Receivers
No full textThe advancement of Rydberg atoms in quantum information technology is driving a paradigm shift from classical radio-frequency (RF) receivers to Rydberg atomic receivers. Capitalizing on the extreme sensitivity of Rydberg atoms to external electromagnetic fields, Rydberg atomic receivers are capable of realizing more precise radio-wave measurements than RF receivers to support high-performance wireless communication and sensing. Although the atomic receiver is developing rapidly in quantum-physics domain, its integration with wireless communications is at a nascent stage. In particular, systematic methods to enhance communication performance through this integration are yet to be discovered. Motivated by this observation, we propose in this paper to incorporate Rydberg atomic receivers into multiple-input-multiple-output (MIMO) communication, a prominent 5G technology, as the first attempt on implementing atomic MIMO receivers. To begin with, we provide a comprehensive introduction on the principles of Rydberg atomic receivers and build on them to design the atomic MIMO receivers. Our findings reveal that signal detection of atomic MIMO receivers corresponds to a non-linear biased phase retrieval (PR) problem, as opposed to the linear Gaussian model adopted in classical MIMO systems. Then, to recover signals from this non-linear model, we modify the Gerchberg-Saxton (GS) algorithm, a typical PR solver, into a biased GS algorithm to solve the biased PR problem. Moreover, we propose a novel Expectation-Maximization GS (EM-GS) algorithm to cope with the unique Rician distribution of the biased PR model. Our EM-GS algorithm introduces a high-pass filter constructed by the ratio of Bessel functions into the iteration procedure of GS, thereby improving the detection accuracy without sacrificing the computational efficiency. Finally, the effectiveness of the devised algorithms and the feasibility of atomic MIMO receivers are demonstrated by theoretical analysis and numerical simulation.</p
Salidroside Improves Oocyte Competence of Reproductively Old Mice by Enhancing Mitophagy
No full textThe decline of oocyte quality with advanced maternal age has a detrimental effect on female fertility. However, there is limited knowledge of therapeutic options and their mechanisms to improve oocyte quality in reproductively older women. In this study, we demonstrated that supplementation of salidroside improves the oocyte quality of reproductively old mice. Salidroside improved the maturation, fertilization, and developmental competence of oocytes from reproductively old mice by maintaining the normal spindle/chromosome structure and mitochondrial function. Oocyte transcriptomic and micro-proteomic analysis revealed that salidroside restores oocyte quality by enhancing mitophagy in reproductively old mice. Our studies provide a new theoretical foundation for utilizing salidroside to improve oocyte quality in reproductively old females in the context of natural fertility or assisted reproduction
Long-term Radio Monitoring of the Fast X-Ray Transient EP 240315a: Evidence for a Relativistic Jet
No full textThe recent launch of Einstein Probe (EP) in early 2024 opened up a new window onto the transient X-ray sky, allowing for real-time discovery and follow-up of fast X-ray transients (FXRTs). Multiwavelength observations of FXRTs and their counterparts are key to characterize the properties of their outflows and, ultimately, identify their progenitors. Here, we report our long-term radio monitoring of EP 240315A, a long-lasting (∼1000 s) high-redshift (z = 4.9) FXRT associated to gamma-ray burst (GRB) 240315C. Our campaign, carried out with the Australian Telescope Compact Array, followed the transient’s evolution at two different frequencies (5.5 and 9 GHz) for 3 months. In the radio light curves we identify an unusual steep rise at 9 GHz, possibly due to a refreshed reverse shock, and a late-time rapid decay of the radio flux, which we interpret as a jet break due to the outflow collimation. We find that the multiwavelength counterpart of EP 240315A is well described by a model of relativistic jet seen close to its axis, with jet half-opening angle θ j ≈ 3° and beaming-corrected total energy E ≃ 4 × 1051 erg, typical of GRBs. These results show that a substantial fraction of FXRTs may be associated to standard GRBs and that sensitive X-ray monitors, such as EP and the proposed HiZ-GUNDAM and Theseus missions, can successfully pinpoint their relativistic outflows up to high redshifts.link_to_subscribed_fulltex
QuickSub: Efficient Iso-Recursive Subtyping
Full text linkMany programming languages need to check whether two recursive types are in a subtyping relation. Traditionally recursive types are modelled in two different ways: equi- or iso- recursive types. While efficient algorithms for subtyping equi-recursive types are well studied for simple type systems, efficient algorithms for iso-recursive subtyping remain understudied. In this paper we present QuickSub: an efficient and simple to implement algorithm for iso-recursive subtyping. QuickSub has the same expressive power as the well-known iso-recursive Amber rules. The worst case complexity of QuickSub is O(nm), where m is the size of the type and n is the number of recursive binders. However, in practice, the algorithm is nearly linear with the worst case being hard to reach. Consequently, in many common cases, QuickSub can be several times faster than alternative algorithms. We validate the efficiency of QuickSub with an empirical evaluation comparing it to existing equi-recursive and iso-recursive subtyping algorithms. We prove the correctness of the algorithm and formalize a simple calculus with recursive subtyping and records. For this calculus we also show how type soundness can be proved using QuickSub. All the results have been formalized and proved in the Coq proof assistant.published_or_final_versio
Interdisciplinary knowledge diffusion of educational research, 2002–2021
No full textSince considered as an independent discipline, education has become more interdisciplinary by absorbing insights from various disciplines. However, there is a gap in understanding how educational knowledge diffuses to other academic fields. Our study seeks to bridge this gap with three specific objectives: 1) Mapping the landscape of literature in the interdisciplinary knowledge diffusion process, 2) Investigating the characteristics of how educational knowledge has diffused to non-educational disciplines, and 3) Examining the non-educational topics that have referenced educational studies. We further delve into secondary disciplines within education for a more in-depth and comprehensive analysis. To achieve these aims, we reviewed primary educational literature published between 2002 and 2021 along with how these sources were cited in non-educational publications. The analysis was structured in three phases accordingly, including descriptive analysis, calculation of interdisciplinary knowledge diffusion metrics, and AI-assisted keyword identification. Our findings point to a growing interdisciplinary influence of education on other fields, as evidenced by various indicators such as the volume, distribution, breadth, diversity, and intensity of knowledge diffusion. The significance of our study lies in its novel research focus, the integration of quantitative and qualitative methodologies, and the extensive volume of publications covered.</p
Viral diversity in bats based on Sri Lankan studies - A mini review
No full textThe emergence of the COVID-19 pandemic and the recent re-emergence of Nipah virus in India has further highlighted the need for identifying animal reservoirs of emerging viral infections, including coronaviruses. Bats have been recognised as the natural reservoir for three out of the ten recent viruses of pandemic concern infecting humans, including, coronaviruses, filoviruses and heniparviruses. In the twenty-first century, there have been several spill-overs of bat-borne viruses to humans and animals. The displacement and re-distribution of bats due to de-forestation and urbanisation have facilitated these spill-overs bringing the native host into closer proximity to wild or domesticated animals and humans. In the future, emergence of pandemics due to virus spill-over is inevitable. Therefore, research on identifying the viruses in bats is of importance. In this review, we focused on reviewing available data on the viruses detected in bats in Sri Lanka using PubMed, Google Scholar and Web of Science using the search terms “Bats”, “Viruses” and “Sri Lanka”. The search strategy produced a total of 41 studies from PubMed (n=11), Google Scholar (n=19) and Web of Science (n=11). After removing duplicate articles (n=22), bat studies done elsewhere (n=10), non-bat studies (n=2) a total of 6 studies were identified as eligible for this review. Among these, three studies were on coronaviruses, two studies on lyssavirus and one study on paramyxovirus. Overall, we identify a need for further surveillance of viruses in bats in Sri Lanka.</p
Enhancing Whole-Person Care Through Mindfulness: Qualitative Insights from Patients with Parkinson’s Disease
Full text linkObjectives: Mindfulness has emerged as a promising mental health and wellness practice, but perceptions and experiences regarding its use for chronic illness care have not been well elucidated. This study explored the perceptions and experiences of people living with Parkinson’s disease on using mindfulness techniques for rehabilitation. Method: This is a qualitative descriptive study with thematic analysis. Sixty-one Chinese people with Parkinson’s disease, participating in a community-based mindfulness rehabilitation program, completed individual semi-structured interviews. Results: Three themes emerged: (1) reshaping illness experience through embodiment, (2) cultivating a sense of community through mindful engagement, and (3) fostering lasting mindfulness impact. Participants viewed mindfulness as transformative, offering psychosocial and spiritual benefits beyond physical relief. Group dynamics, mindful interactions, and culturally relevant affirmations were crucial factors in motivating participants in mindful engagement. Challenges in experiential learning highlighted the need for tailored support and resources for sustained mindfulness practice. Conclusions: The findings emphasize the transformative potential of mindfulness in empowering self-care practices through a whole-person approach. Integrating mindfulness into gerontological care is crucial to optimize holistic wellness, particularly for people with Parkinson’s disease. Efforts should focus on personalizing disease-specific mindfulness techniques, expanding mind–body experiences beyond goal-driven practice, and fostering a supportive environment for routine integration.published_or_final_versio
Estimation of trajectory of COVID-19 vaccines effectiveness against infection
Full text linkThis large-scale cohort study conducted in Hong Kong examined the time-varying protective effects of various COVID-19 vaccines and dosing regimens against the Omicron BA.1/BA.2 variants. An innovative pharmacokinetic/pharmacodynamic model was employed to estimate the trajectory of vaccine effectiveness over time. Results indicated that the maximum protection for a single dose reached 0.120 for CoronaVac and 0.171 for Comirnaty. The peak protective effectiveness for the second and third doses were observed at 0.348 and 0.522, respectively. In a 4-dose regimen, CoronaVac demonstrated a maximum protective effectiveness of 0.548, stabilizing at 0.487, while Comirnaty achieved a maximum effectiveness of 0.784, stabilizing at 0.714 six months after the administration of the last dose. The vaccine effectiveness exhibited a rising and then declining pattern, peaking approximately 1–2 months post-vaccination. Understanding waning immunity is crucial for optimizing vaccination strategies and policies as viral evolution continues. This real-world study captured changing dynamics that may differ from clinical trials with limited follow-up, providing essential evidence to guide the optimization of vaccination efforts. Ongoing monitoring of vaccine effectiveness remains critical as the viral landscape evolves. Objectives: This study aims to investigate the time-varying protective effects of various COVID-19 vaccines and dosing regimens against infections caused by the Omicron BA.1/BA.2 in Hong Kong. Methods: This territory-wide cohort study from Hong Kong combined vaccination records, confirmed COVID-19 cases, and census data from January 2022 to May 2022 to comprehensively analyze the time-varying protective effects of different COVID-19 vaccines and dosing regimens against Omicron BA.1 and BA.2 infections. A 4-parameter pharmacokinetic/pharmacodynamic model was used to estimate the trajectory of vaccine effectiveness over time. Results: Among 6.2 million adults, the maximum protective effectiveness for a single vaccine dose reached 0.120 for CoronaVac and 0.171 for Comirnaty. For the second and third doses, peak effectiveness were observed at 0.348 for CoronaVac and 0.522 for Comirnaty. Notably, a 4-dose regimen resulted in maximum protections of 0.548 for CoronaVac and 0.785 for Comirnaty, which stabilized at 0.487 and 0.714, respectively, six months following the last doses. The vaccine effectiveness exhibited a rising then declining pattern, peaking around 1–2 months post-vaccination, underscoring the importance of ongoing vaccination strategies. Conclusions: Understanding the waning of vaccine protection over time is critical for informing optimal vaccination strategies, booster schedules, and public health policies. This real-world study can capture changing dynamics that may differ from clinical trials which have more limited follow-up periods, and can provide crucial evidence to guide optimization of vaccination strategies. Ongoing monitoring of vaccine effectiveness remains crucial as the viral evolution continues.published_or_final_versio
Argon-based geochronology: Advances, limitations and perspectives
No full textGiven that K constitutes about 3 wt.% of Earth's crust and is present in most rock-forming minerals, and that Ar diffusion in minerals is temperature-dependent, Ar-based geochronology (40Ar/39Ar and K-Ar dating) can date most rocks and also reveal their thermal history. This paper reviews recent advances and longstanding limitations in 40Ar/39Ar and K-Ar geochronology, and provides perspectives into future research on Ar-based geochronometers. Over the past two decades, multi-collector noble gas mass spectrometry has witnessed remarkable advancements in both sensitivity and resolution. Successive upgrades of mass spectrometer generations have significantly enhanced the precision of Ar isotope measurements, enabling a comprehensive revision and optimization of 40Ar/39Ar dating standard minerals. To achieve high-precision 40Ar/39Ar dating and minimize inter-laboratory discrepancies, researchers are focusing on refining the potassium decay constant, developing standardized mineral separation techniques, and harmonizing irradiation and data processing protocols. These efforts are pivotal for improving the analytical precision of low-K and young samples, thereby expanding the application frontiers of 40Ar/39Ar geochronology. For in situ planetary dating, the K/Ar method currently remains the only feasible radiometric technique among radioactive isotope systems. Addressing challenges in simultaneous K and Ar measurements will facilitate streamlined acquisition of reliable datasets. Moreover, research is advancing toward a deeper understanding of Ar diffusion behavior in minerals - beyond temperature-dependent volume diffusion - to clarify its impact on 40Ar/39Ar data interpretation and geological significance. To further advance argon-based geochronology, the scientific community is committed to continuous exploration and resolution of methodological limitations inherent in these dating approaches.</p
Gamified self-regulated learning improves EFL Reading comprehension, motivation, self-regulation skills and process patterns: Quasi-experiment with process mining
No full textThis study investigates the effects of a flipped gamified self-regulated learning (SRL) approach in an English as a Foreign Language (EFL) classroom for first-year undergraduates. Using a quasi-experiment with process mining approach, 177 students were divided into two groups: a gamified experimental group (N = 91) and a non-gamified control group (N = 86). The findings revealed that the gamified SRL approach significantly improved English reading comprehension and motivation, as evidenced by enhanced intrinsic value and consistently higher voluntary task completion. Moreover, SRL skills were enhanced, as shown by survey results and high engagement with SRL strategies observed in the trace data. Process mining analyses using First-Order Markov Models further demonstrated that gamification fostered more dynamic SRL behaviors, including greater engagement with scaffolds and a stronger focus on evaluative learning strategies. These results highlight the potential of the gamified SRL approach to enhance students' SRL skills, motivation, and improve learning outcomes. This study offers actionable insights for designing effective interventions that integrate SRL scaffolds with motivational elements to support students' success in flipped learning environments. </p