Epidemics and pandemics : Covid-19 and the ‘‘drop of honey effect’’

Purpose: The aim of this paper is the use of the “drop of honey effect” to explain the spread of Covid-19. Approach/Methodology/Design: After Covid-19 appearance in Wuhan, in the Chinese province of Hubei, by December, 2019, it spread all over the world. The World Health Organization declared it as pandemic in March 11, 2020. The infection is highly contagious and made thousands of deaths around the world. Timely decisions are key for the control of the dissemination. The “drop of honey effect” results as an important framework to explain the Covid-19 spread. Findings: An opportune decision in a very initial moment could have made all the difference in the virus spread. Practical Implications: The study will contribute positively for the understanding of the importance of well-timed decisions for governments, world organizations, academia, companies and people, each one on a different dimension’s level. Originality/Value: This study presents the “drop of honey effect” as an original and very suitable framework to explain the way how the virus spread all over the world after the virus in Wuhan began to infect people.peer-reviewe

Investigation of high-order, high-resolution methods for axisymmetric turbulent jet usin ILEs

This Philosophiae Doctor thesis presents the motivation, objectives and reasoning behind the undertaken project. This research, study the capability of compressible Implicit Large Eddy Simulation (ILES) in predicting free shear layer flows, under different free stream regimes (Static and Co-flow jets). Unsteady flows or jet flows are non-uniform in structure, temperature, pressure and velocity. Turbulent mixing is of particular importance for the developing of this class of flows. As a shear layer is formed immediately downstream of the jet exhaust, an early linear instability involving exponential growth of small perturbations is introduced at the jet discharge. Beyond this development stage, in the non-linear Kelvin-Helmholtz instability region large scale vortex rings roll up, and their dynamics of formation and merging become the defining feature of the transitional shear flow into fully developed regime. This class of flows is particularly relevant to numerical predictions, as the extreme nature of the flow in question is considered as a benchmark; however, experimental data should be selected carefully as some results are controversial. To qualify the behaviour of unsteady flows, some important criteria have been selected for the analysis of the flow quantities at different regions of the flow field (average velocities, Reynolds stresses and dissipation rates). A good estimation of high-order statistics (Standard Deviation, Skewness and Kurtosis) correspond to mathematical steadiness and convergence of results. From the physical point of view, similarity analysis between jet’s wake sections reveals physical steadiness in results. Spectral analysis of the different regions of the flow field could be used as a sign that the energy cascade is correctly predicted or efficiently enough since this is where the smallest scales are usually present and which in effect require to be modelled by the different numerical schemes. Cont/d

Modelling an idle building case through SWOT analysis and fuzzy DEMATEL – a study on anti-commons

The situation of buildings degradation is very severe in many cities in the world. The case of a degraded building is studied in this article. The building becomes ruined because owners do not agree about what to do with the building and no one can use it without the consent of the others. Besides, time makes the building become with a lower value. After a long period of degradation, the question “what doing now?” is posed. Considering the situation of many degraded buildings, the present study aims to analyze a possible cause and work a situation of anti-commons concerning a building owned by several holders having each one exclusion rights. We use SWOT Analysis to build strategies for this anti-commons’ real estate case. Then Fuzzy DEMATEL model is applied to understand the relations between strategies for a final decision. Conclusions allow understanding the relations between strategies and how they influence each other to get a final decision for this problem. For our case, we recommend a concrete strategy to the owners after evaluating the preferences of the decision makers.peer-reviewe

Redescription of <i>Cercopithifilaria bainae</i> Almeida &amp; Vicente, 1984 (Spirurida, Onchocercidae) from a dog in Sardinia, Italy

Background Three species of the genus Cercopithifilaria have been morphologically and molecularly characterized in dog populations in southern Europe: Cercopithifilaria grassii (Noè, 1907), Cercopithifilaria sp. sensu Otranto et al., 2011 (reported as Cercopithifilaria sp. I), and Cercopithifilaria sp. II sensu Otranto et al., 2012. The adults of Cercopithifilaria sp. I have remained unknown until the present study. Methods The material originated from a dog from Sardinia (Italy) diagnosed with dermal microfilariae of Cercopithifilaria sp. I. The holotype and three paratypes of Cercopithifilaria bainae Almeida &amp; Vicente, 1984, described from dogs in Brazil, were studied as comparative material. A cox1 (~689 bp) and 12S (~330 bp) gene fragments were amplified and phylogenetic analysis carried out. Results The highest numbers of adult nematodes (82%) were collected in the sediment of the subcutaneous tissues of the trunk (n = 37) and forelimbs (n = 36). The morphology of the adult nematodes and microfilariae collected from the dog in Sardinia corresponded to those of C. bainae. All cox1 and 12S gene sequences showed a high homology (99-100%) with sequences from microfilariae of Cercopithifilaria sp. I. Conclusions The morphological and molecular identity of the microfilariae of C. bainae overlap those described previously as Cercopithifilaria sp. sensu Otranto et al., 2011 (=Cercopithifilaria sp. I). Therefore, the present study reports the occurrence of C. bainae in Europe, for the first time after its description and the single record in Brazil. C. bainae appears to be highly diffused in dog populations in southern Europe. The phylogenetic analyses based on cox1 and 12S do not reveal the three species of Cercopithifilaria parasitizing dogs as a monophyletic group, which suggests that they have derived independently by host switching

Transoesophageal Echocardiography for Monitoring Liver Surgery: Data from a Pilot Study

A pilot study aimed to introduce intraoperative monitoring of liver surgery using transoesophageal echocardiography (TEE) is described. A set of TEE measurements was established as a protocol, consisting of left atrial (LA) dimension at the aortic valve plane; mitral velocity flow integral, calculation of stroke volume and cardiac output (CO); mitral annular plane systolic excursion; finally, right atrial area. A total of 165 measurements (on 21 patients) were performed, 31 occurring during hypotension. The conclusions reached were during acute blood loss LA dimension changed earlier than CVP, and, in one patient, a dynamic left ventricular (LV) obstruction was observed; in 3 patients a transient LV systolic dysfunction was documented. The comparison between 39 CO paired measurements obtained by TEE and PiCCO2 revealed a statistically significant correlation (P < 0.001, r = 0.83). In this pilot study TEE successfully answered the questions raised by the anesthesiologists. Larger cohort studies are needed to address this issue

Biological compatibility between two temperate lineages of brown dog ticks, Rhipicephalus sanguineus (sensu lato)

Background: The brown dog tick Rhipicephalus sanguineus (sensu stricto) is reputed to be the most widespread tick of domestic dogs worldwide and has also been implicated in the transmission of many pathogens to dogs and humans. For more than two centuries, Rh. sanguineus (s.s.) was regarded as a single taxon, even considering its poor original description and the inexistence of a type specimen. However, genetic and crossbreeding experiments have indicated the existence of at least two distinct taxa within this name: the so-called "temperate" and "tropical" lineages of Rh. sanguineus (sensu lato). Recent genetic studies have also demonstrated the existence of additional lineages of Rh. sanguineus (s.l.) in Europe and Asia. Herein, we assessed the biological compatibility between two lineages of Rh. sanguineus (s.l.) found in southern Europe, namely Rhipicephalus sp. I (from Italy) and Rhipicephalus sp. II (from Portugal). Methods: Ticks morphologically identified as Rh. sanguineus (s.l.) were collected in southern Portugal and southern Italy. Tick colonies were established and crossbreeding experiments conducted. Morphological, biological and genetic analyses were conducted. Results: Crossbreeding experiments confirmed that ticks from the two studied lineages were able to mate and generate fertile hybrids. Hybrid adult ticks always presented the same genotype of the mother, confirming maternal inheritance of mtDNA. However, larvae and nymphs originated from Rhipicephalus sp. I females presented mtDNA genotype of either Rhipicephalus sp. I or Rhipicephalus sp. II, suggesting the occurrence of paternal inheritance or mitochondrial heteroplasmy. While biologically compatible, these lineages are distinct genetically and phenotypically. Conclusions: The temperate lineages of Rh. sanguineus (s.l.) studied herein are biologically compatible and genetic data obtained from both pure and hybrid lines indicate the occurrence of paternal inheritance or mitochondrial heteroplasmy. This study opens new research avenues and raises question regarding the usefulness of genetic data and crossbreeding experiments as criteria for the definition of cryptic species in ticks

History of scientific and academic production in mathematics education: pointing out elements for a research agenda

The aim of this paper is to list elements for the construction of an agenda for scientific and academic research in mathematics education in Brazil, under a historical perspective. In face of the urgency and the necessity for the construction of this investigative agenda, we choose to take a position that marks some initial routes, specific to the intentions of this text: the practice of history under a Foucauldian perspective, putting in evidence the production of knowledge, which is not disconnected from the dynamics of power relations; and the possible consequences resulting from the formation and action of individuals with master and doctorate degrees in mathematics education in Brazil. With this text, we expect to attract greater interest, within the field of History of Mathematics Education, for the formation and consolidation of mathematics education as a field of knowledge in the Brazilian scenario

Dynamical amplification of magnetoresistances and Hall currents up to the THz regime

Spin-orbit-related effects offer a highly promising route for reading and writing information in magnetic units of future devices. These phenomena rely not only on the static magnetization orientation but also on its dynamics to achieve fast switchings that can reach the THz range. In this work, we consider Co/Pt and Fe/W bilayers to show that accounting for the phase difference between different processes is crucial to the correct description of the dynamical currents. By tuning each system towards its ferromagnetic resonance, we reveal that dynamical spin Hall angles can non-trivially change sign and be boosted by over 500%, reaching giant values. We demonstrate that charge and spin pumping mechanisms can greatly magnify or dwindle the currents flowing through the system, influencing all kinds of magnetoresistive and Hall effects, thus impacting also dc and second harmonic experimental measurements.Comment: 19 pages, 4 figures, Supplementary Informatio

Un caso de estudio dsobre el control de servicios de TI en una empresa pequeña

This paper shows a case study related to the implementation of the financial management process in a small enterprise whose core business is not Information Technology (IT). A brief description of ITIL v3 financial management process is presented. Then, the target enterprise and its IT infrastructure are described. Finally, it shows how it has begun to implement the financial management process through IT costs accounting of the previous year, which makes the baseline, to make the IT budget for the current year

Assessing the introduction of Angolan indigenous languages in the educational system in Luanda: a language policy perspective

M.A., Faculty of Humanities, University of the Witwatersrand, 2011The aim of this study was to find out the agenda behind language policy in Angola, and in particular it assesses the introduction of the Angolan indigenous languages in the Angolan educational system in Luanda and why the chosen languages and not others, as well as providing my contribution as a teacher and researcher in the matters of educational language policy. To do so, it analysed two most relevant policy documents that provides legal support to the policy and three newspaper articles that reacted to this issue. A broad review of literature on the impact of colonial and post-colonial language ideologies in the country, including the historicity of the policy makers was done. Qualitative research tools were used to gather and analyse the data. Fifteen interviews and questionnaires were conducted to gather the views of grassroots and the policy implementers. This research was the first study in this field in Angola. The study found that Kimbundu is being also being used as a medium of instruction in Luanda where children have Portuguese as their first language which is the opposite of what the policy UNESCO’s persuasive campaign for mother-tongue education and the government claims was happening. Furthermore, the research established that there is a parallel between the Angolan colonial and post-colonial language policies. Therefore, I conclude that by doing the inverse there is a government hidden agenda behind the policy which is to preserve Portuguese colonial language ideology and maintain social discrimination on the basis of language. Hence, I recommended that the government reviewed the whole set of strategies applied to implement the policy by using more inclusive practices