A Theoretical Framework for Effective Online Learning

A key, overarching goal for any committed educator is to ensure that the learner has a meaningful and memorable learning experience while achieving the desired learning outcomes. In this paper it is argued that in order to achieve such a goal, a strategy needs to be put in place that is capable of providing students with a fully integrated, all-encompassing learning environment. The reasoning, simply, is that learning will not necessarily emanate from one specific source and when it happens, it will occur through different means, for different people. One of the great strengths of the online learning space is that, harnessing the power of the various information and communication technologies (ICTs), there is greater scope for catering for individual learning needs. With this in mind, the paper puts forward a framework that comprises a number of overlapping \u27sub-environments\u27 which, together, provide the scaffolding considered essential for the construction of a truly holistic learning environment. To illustrate how this framework for effective online learning can be operationalised, the authors refer to the case of Universitas 21 Global, an institution which offers completely online programs to post-graduate students in more than 40 countries around the world

Spin Dynamics of Planets in Resonant Chains

About a dozen exoplanetary systems have been discovered with three or more planets participating in a sequence of mean-motion resonances. The unique and complex architectures of these so-called "resonant chains" motivate efforts to characterize their planets holistically. In this work, we perform a comprehensive exploration of the spin-axis dynamics of planets in resonant chains. Planetary spin states are closely linked with atmospheric dynamics and habitability and are thus especially relevant to resonant chains like TRAPPIST-1, which hosts several temperate planets. Considering a set of observed resonant chains, we calculate the equilibrium states of the planetary axial tilts ("obliquities"). We show that high obliquity states exist for $\sim60\%$ of planets in our sample, and many of these states can be stable in the presence of tidal dissipation. Using case studies of two observed systems (Kepler-223 and TOI-1136), we demonstrate how these high obliquity states could have been attained during the initial epoch of disk-driven orbital migration that established the resonant orbital architectures. We show that the TRAPPIST-1 planets most likely have zero obliquities, with the possible exception of planet d. Overall, our results highlight that both the orbital and spin states of resonant chains are valuable relics of the early stages of planet formation and evolution.Comment: Accepted for publication in Ap

Particle-in-cell experiments examine electron diffusion by whistler-mode waves: 1. Benchmarking with a cold plasma

Using a particle-in-cell code, we study the diffusive response of electrons due to wave particle interactions with whistler-mode waves. The relatively simple configuration of field-aligned waves in a cold plasma is used in order to benchmark our novel method, and to compare with previous works that used a different modelling technique. In this boundary-value problem, incoherent whistler-mode waves are excited at the domain boundary, and then propagate through the ambient plasma. Electron diffusion characteristics are directly extracted from particle data across all available energy and pitch-angle space. The ‘nature’ of the diffusive response is itself a function of energy and pitch-angle, such that the rate of diffusion is not always constant in time. However, after an initial transient phase, the rate of diffusion tends to a constant, in a manner that is consistent with the assumptions of quasilinear diffusion theory. This work establishes a framework for future investigations on the nature of diffusion due to whistler-mode wave-particle interactions, using particle-in-cell numerical codes with driven waves as boundary value problems

Myristica lowiana Phytochemicals as Inhibitor of Plasmid Conjugation in Escherichia coli

Hexane extract and methanol fraction from the stem bark of Myristica lowiana specifically and significantly inhibited the conjugal transfer of the IncW plasmid R7K, a plasmid which harbors ampicillin-, streptomycin-, and spectinomycin-resistant genes. The transfer of this plasmid via the conjugative pilli of Escherichia coli was reduced by 76.5 ± 2.0% and 79.0 ± 1.2% by hexane extract and methanol fraction of M. lowiana, respectively. The hexane extract exhibited significant anti-conjugant activity at a non-cytotoxic concentration of 100 mg/L as assessed against adult human dermal fibroblast cells. The hexane extract and methanol fraction were screened using phytochemical tests, NMR spectroscopy, IR spectroscopy, and high-resolution electrospray ionization mass spectrometry (HRESIMS) and were found to contain terpenoids, sterols, and fatty acids

MAP Kinase-Interacting Kinases—Emerging Targets against Cancer

Mitogen-activated protein kinase (MAPK)-interacting kinases (Mnks) regulate the initiation of translation through phosphorylation of eukaryotic initiation factor 4E (eIF4E). Mnk-mediated eIF4E activation promotes cancer development and progression. While the phosphorylation of eIF4E is necessary for oncogenic transformation, the kinase activity of Mnks seems dispensable for normal development. For this reason, pharmacological inhibition of Mnks could represent an ideal mechanism-based and nontoxic therapeutic strategy for cancer treatment. In this review, we discuss the current understanding of Mnk biological roles, structures, and functions, as well as clinical implications. Importantly, we propose different strategies for identification of highly selective small molecule inhibitors of Mnks, including exploring a structural feature of their kinase domain, DFD motif, which is unique within the human kinome. We also argue that a combined targeting of Mnks and other pathways should be considered given the complexity of cancer

International Comparison of Tertiary Education Systems

This report is designed to review high performing tertiary systems internationally (Germany, Norway, the United Kingdom, Korea, Singapore and New Zealand) and compare these systems to Australia. This review highlights best practice in international tertiary education systems as well as system weaknesses by considering the following criteria for each country of interest: Tertiary education system performance, including participation, attainment, labour market outcomes, and public and private returns for tertiary education; The national context, including the shape of the broader education system, and relevant demographic and economic characteristics; The structure of tertiary education systems, including linkages between higher education and vocational education and training; Tertiary education qualifications, types of institutions and admissions requirements; Governance, accreditation and quality assurance; and Funding. The report also includes an investigation of tertiary governance structures and considerations as they relate to the interaction between VET and higher education sectors. Findings from the report are intended to inform the Commonwealth Department of Education’s tertiary education policy and improve understanding of critical attributes demonstrated by high performing tertiary systems to support the work of the Australian Universities Accord panel

On the design of sparse but efficient structures in operations

It is widely believed that a little flexibility added at the right place can reap significant benefits for operations. Unfortunately, despite the extensive literature on this topic, we are not aware of any general methodology that can be used to guide managers in designing sparse (i.e., slightly flexible) and yet efficient operations. We address this issue using a distributionally robust approach to model the performance of a stochastic system under different process structures. We use the dual prices obtained from a related conic program to guide managers in the design process. This leads to a general solution methodology for the construction of efficient sparse structures for several classes of operational problems. Our approach can be used to design simple yet efficient structures for workforce deployment and for any level of sparsity requirement, to respond to deviations and disruptions in the operational environment. Furthermore, in the case of the classical process flexibility problem, our methodology can recover the k-chain structures that are known to be extremely efficient for this type of problem when the system is balanced and symmetric. We can also obtain the analog of 2-chain for nonsymmetrical system using this methodology. This paper was accepted by Yinyu Ye, optimization. </jats:p

Disruption risk mitigation in supply chains: The risk exposure index revisited

A novel approach has been proposed in the literature using the time-to-recover (TTR) parameters to analyze the risk-exposure index (REI) of supply chains under disruption. This approach is able to capture the cascading effects of disruptions in the supply chains, albeit in simplified environments; TTRs are deterministic, and at most, one node in the supply chain can be disrupted. In this paper, we propose a new method to integrate probabilistic assessment of disruption risks into the REI approach and measure supply chain resiliency by analyzing the worst-case conditional value at risk of total lost sales under disruptions. We show that the optimal strategic inventory positioning strategy in this model can be fully characterized by a conic program. We identify appropriate cuts that can be added to the formulation to ensure zero duality gap in the conic program. In this way, the optimal primal and dual solutions to the conic program can be used to shed light on comparative statics in the supply chain risk mitigation problem. This information can help supply chain risk managers focus their mitigation efforts on critical suppliers and/or installations that will have a greater impact on the performance of the supply chain when disrupted.Accepted versio

Updated Parameters and a New Transmission Spectrum of HD 97658b

Recent years have seen increasing interest in the characterization of sub-Neptune-sized planets because of their prevalence in the Galaxy, contrasted with their absence in our solar system. HD 97658 is one of the brightest stars hosting a planet of this kind, and we present the transmission spectrum of this planet by combining four Hubble Space Telescope transits, 12 Spitzer/IRAC transits, and eight MOST transits of this system. Our transmission spectrum has a higher signal-to-noise ratio than those from previous works, and the result suggests that the slight increase in transit depth from wavelength 1.1–1.7 μm reported in previous works on the transmission spectrum of this planet is likely systematic. Nonetheless, our atmospheric modeling results are inconclusive, as no model provides an excellent match to our data. Nonetheless, we find that atmospheres with high C/O ratios (C/O ≳ 0.8) and metallicities of ≳100× solar metallicity are favored. We combine the mid-transit times from all of the new Spitzer and MOST observations and obtain an updated orbital period of P = 9.489295 ± 0.000005, with a best-fit transit time center at T₀ = 2456361.80690 ± 0.00038 (BJD). No transit timing variations are found in this system. We also present new measurements of the stellar rotation period (34 ± 2 days) and stellar activity cycle (9.6 yr) of the host star HD 97658. Finally, we calculate and rank the Transmission Spectroscopy Metric of all confirmed planets cooler than 1000 K and with sizes between 1 R⊕ and 4 R⊕. We find that at least a third of small planets cooler than 1000 K can be well characterized using James Webb Space Telescope, and of those, HD 97658b is ranked fifth, meaning that it remains a high-priority target for atmospheric characterization