65 research outputs found
Exploring the ethical dilemmas of afro-centric social media use through agent-based modeling: A review
Social media (SM) has become indispensable for individuals and workplaces/organizations in Africa and beyond. Therein, ethical concerns are posed due to the inability to create virtual boundaries (VM), the intractability of guidelines for managers and other unintended risks/consequences. Operations research was used for modeling ethical concerns but have been defeated due to reasons of several ethical values and various assessment criteria for stakeholders. Consequently, this review paper initially x-rays the import of ethical dilemmas in older studies so as to conceive a strategy characterized by engaging stakeholders that utilize SM via Agent-Based Modeling (ABM), in such a manner that ethics can be evaluated. Additionally, it presented the rudiments of social media ABM explorations and the peculiarities of Africa. Finally, the review provided a suitable methodology and sheds light on the possible challenges of ABM implementation. Besides the benefit of increased patronage, the agent technology may also constitute a pedagogical tool for learning ethical behavior. Moreover, it is our hope that with the involvement of experts of related disciplines in Africa, attendant theories are formalized and used for building agent models that allows ethical decision making, weighing of pros and cons, analyzing differences and dimensions inherent in VM creation
Thermal Conversion of Guanylurea Dicyanamide into Graphitic Carbon Nitride via Prototype CNx Precursors
Guanylurea dicyanamide, [(H2N)C(-O)NHC(NH2)2][N(CN)2], has been synthesized by ion exchange reaction in aqueous solution and structurally characterized by single-crystal X-ray diffraction (C2/c, a = 2249.0(5) pm, b = 483.9(1) pm, c = 1382.4(3) pm, β = 99.49(3)°, V = 1483.8(5) × 106 pm3, T = 130 K). The thermal behavior of the molecular salt has been studied by thermal analysis, temperature-programmed X-ray powder diffraction, FTIR spectroscopy, and mass spectrometry between room temperature and 823 K. The results were interpreted on a molecular level in terms of a sequence of thermally induced addition, cyclization, and elimination reactions. As a consequence, melamine (2,4,6-triamino-1,3,5-triazine) is formed with concomitant loss of HNCO. Further condensation of melamine yields the prototypic CNx precursor melem (2,6,10-triamino-s-heptazine, C6N7(NH2)3), which alongside varying amounts of directly formed CNxHy material transforms into layered CNxHy phases without significant integration of oxygen into the core framework owing to the evaporation of HNCO. Thus, further evidence can be added to melamine and its condensation product melem acting as “key intermediates” in the synthetic pathway toward graphitic CNxHy materials, whose exact constitution is still a point at issue. Due to the characteristic formation process and hydrogen content a close relationship with the polymer melon is evident. In particular, the thermal transformation of guanylurea dicyanamide clearly demonstrates that the formation of volatile compounds such as HNCO during thermal decomposition may render a large variety of previously not considered molecular compounds suitable CNx precursors despite the presence of oxygen in the starting material
Structural matters in HTSC; the origin and form of stripe organization and checker boarding
The paper deals with the controversial charge and spin self-organization
phenomena in the HTSC cuprates, of which neutron, X-ray, STM and ARPES
experiments give complementary, sometimes apparently contradictory glimpses.
The examination has been set in the context of the boson-fermion, negative-U
understanding of HTSC advocated over many years by the author. Stripe models
are developed which are 2q in nature and diagonal in form. For such a geometry
to be compatible with the data rests upon both the spin and charge arrays being
face-centred. Various special doping concentrations are closely looked at, in
particular p = 0.1836 or 9/49, which is associated with the maximization of the
superconducting condensation energy and the termination of the pseudogap
regime. The stripe models are dictated by real space organization of the holes,
whereas the dispersionless checkerboarding is interpreted in terms of
correlation driven collapse of normal Fermi surface behaviour and response
functions. The incommensurate spin diffraction below the resonance energy is
seen as in no way expressing spin-wave physics or Fermi surface nesting, but is
driven by charge and strain (Jahn-Teller) considerations, and it stands
virtually without dispersion. The apparent dispersion comes from the downward
dispersion of the resonance peak, and the growth of a further incoherent
commensurate peak ensuing from the falling level of charge stripe organization
under excitation.Comment: 49 pages with 8 figure
Causal and associational language in observational health research: A systematic evaluation.
This is the final version. Available from Oxford University Press via the DOI in this record. Data, data analysis code, and materials are available on
the Open Science Framework project https://osf.io/jtdaz/.We estimated the degree to which language used in the high profile medical/public health/epidemiology literature implied causality using language linking exposures to outcomes and action recommendations; examined disconnects between language and recommendations; identified the most common linking phrases; and estimated how strongly linking phrases imply causality. We searched and screened for 1,170 articles from 18 high-profile journals (65 per journal) published from 2010-2019. Based on written framing and systematic guidance, three reviewers rated the degree of causality implied in abstracts and full text for exposure/outcome linking language and action recommendations. Reviewers rated the causal implication of exposure/outcome linking language as None (no causal implication) in 13.8%, Weak 34.2%, Moderate 33.2%, and Strong 18.7% of abstracts. The implied causality of action recommendations was higher than the implied causality of linking sentences for 44.5% or commensurate for 40.3% of articles. The most common linking word in abstracts was "associate" (45.7%). Reviewers' ratings of linking word roots were highly heterogeneous; over half of reviewers rated "association" as having at least some causal implication. This research undercuts the assumption that avoiding "causal" words leads to clarity of interpretation in medical research.Marie Skłodowska-Curie grantAustralian Research CouncilNational Institute of Mental HealthNational Institute of Mental HealthNational Institute of Biomedical Imaging and BioengineeringNational Center for Advancing Translational Sciences UCLA Clinical Translational Science InstituteBloomberg American Health InitiativeKaren Toffler Charity Trus
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