Designing Indicators for a Placement Test: Drawbacks and Affordances

One of the greatest challenges when it comes to assessment is the lack of clarity in the objectives or, to make it worse, the absence of objectives whatsoever for what results the curriculum, course, or the test instrument wishes to achieve. According to Raupp and Reichle (2003), this kind of information usually exists as expectations pushing the examiner to transform expectations, general goals or poorly stated objectives into measurable objectives. Raupp and Reichle (2003) emphasize that very precise indicators need to be written or selected to measure whether or not the course/curriculum objectives proposed were achieved. However, this job becomes rather challenging when objectives are not clearly stated or are too vague. Indicators, then, ideally, resonate curricular goals, teaching methodologies, and testing. If one of these components is not well calibrated or is dissonant with the others, the whole assessment process is jeopardized (CEFRL, 2007). Indicators for placement testing, then, need to be carefully written or selected so that they can reflect an intended proficiency level as well as the school’s curricular goals, teaching methodologies, and testing procedures (Brown, 2004; Richards, 2009). At the Federal University of Espírito Santo’s Language Center (CL), the discontentment of instructors and coordination staff with the lack of reliability, validity and practicality with the CL’s placement test motivated debates and work on the refinement of the indicators used for the referred exam. Through a literature review and with a practical example from a language center in Brazil, this paper addresses how teachers/practitioners can make informed decisions to write or select their own indicators for placement testing and, therefore, monitor the progress of their students and/or the success or pitfalls of their classes/programs/curricula and plan for possible welcome changes

CBmeter- a new medical device for early screening of metabolic diseases

Type 2 diabetes mellitus (T2DM) is a highly prevalent disease worldwide which is asymptomatic in about 44% of patients being critical to search for new ways of early diagnosis. Recent studies have demonstrated that the etiology of this disease may be associated with alterations in the function of the carotid body (CB), a chemosensor organ located within the bifurcation of the carotid artery. In animal models of metabolic syndrome it was observed that the CBs are overactivated, underlying diseases such as obesity, hypertension and T2DM. This discovery provided a new paradigm in the neuroendocrinology field, suggesting that diagnostic function of the CBs has predictive value for the development of metabolic diseases. Despite this fact, it is not common in clinical practice to look at the CBs as organs associated with endocrine dysfunction and we believe this is probably due to the nonexistence of a user-friendly, portable medical device that diagnosis the function of the CBs.info:eu-repo/semantics/publishedVersio

Growth, structural change and technological capabilities Latin America in a comparative perspective

Countries differ in terms of technological capabilities and complexity of production structures.According to that, countries may follow different development strategies: one based onextracting rents from abundant endowments, such as labor or natural resources, and the otherfocused on creating rents through intangibles, basically innovation and knowledgeaccumulation. The present article studies international convergence and divergence, linkingstructural change with trade and growth through a North South Ricardian model. The analysisfocuses on the asymmetries between Latin America and mature and catching up economies.Empirical evidence supports that a shift in the composition of the production structure in favorof R&D intensive sectors allows achieving higher rates of growth in the long term andincreases the capacity to respond to demand changes. A virtuous export-led growth requireslaggard countries to reduce the technological gap with respect to more advanced ones. Hence,abundance of factor endowments requires to be matched with technological capabilitiesdevelopment for countries to converge in the long term.

Residual biomass characterization and evaluation of its influence on pyrolysis processes

Biomass is extensively accepted as one of the main potential sources for sustainable and renewable generation of fuels, chemicals and other carbon-based materials. Many advantages are reported using biomass as an energy source, such as being a non-polluting alternative and its carbon neutrality. Numerous processes can be used to convert biomass, and namely the pyrolysis process is a renewable, economical, and efficient way to produce chemicals and/or energy. Therefore, pyrolysis is an available technology for biomass conversion into energy. It consists of a thermal decomposition process with the absence of oxygen, converting biomass into 3 fractions: biochar (solid fraction), bio-oil (liquid fraction) and gases. Hence, pyrolysis is a recognized industrial process for biomass energy and chemical conversion. The bio-oil and biochar can be used as a fuel and as fertilizer respectively, and the gases can be recycled back into the process. Biomass samples were characterized by proximate analysis, determining fixed carbon, moisture, volatiles and ashes composition, and by ultimate analyses, determining the content of C, H, N, S and O. The content of hemicellulose, lignin and cellulose was also determined. The methodologies are described elsewhere [1-3] and all characterizations were performed on a dry basis. Pyrolysis tests were performed in a fixed-bed vertical pyrolysis oven, with a maximum temperature of 500 to 700C, variable heating rate up to 50C/min, retention time of 0.5 h, and N2 flow of 20 mL/min. The bio-oil and biochar were qualitatively characterized using FTIR and the products distribution was analyzed in relation to the biomass samples previous characterizationThis work is funded by the Portuguese Foundation of Science and Technology (FCT) within the framework of the SUBe Project, ref.: PCIF/GVB/0197/2017. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CIMO (UIDB/00690/2020 and UIDP/00690/2020) and SusTEC (LA/P/0007/2021).info:eu-repo/semantics/publishedVersio

Biomass characterization and pyrolysis towards bio-oil production

One of the greatest challenges humanity has to deal with nowadays is climate change. An important strategy to mitigate climate change is replacing fossil fuels with renewable sources of energy [1]. Biomass is considered one of the world's most promising renewable energy sources, mainly due to its nearly endless availability. Worldwide, each year plants convert approximately 125 gigatons of carbon from atmosphere into biomass, which is equivalent to almost 300 million tons of oil per day [2]. There are many advantages in using biomass as an energy source, namely its carbon neutrality and being a non-polluting source. In this context, the main technologies for fuel and/or energy production from biomass are pyrolysis, gasification, or combustion.This work is funded by the Portuguese Foundation of Science and Technology (FCT) within the framework of the SUBe Project, ref.:PCIF/GVB/0197/2017.info:eu-repo/semantics/publishedVersio

Evaluation of temperature on the pyrolysis of residual biomass

One of the greatest challenges humanity has to deal with nowadays is climate change. In this context, residual biomass is considered a critical potential source for its mitigation, as biomass is a renewable, sustainable and nearly endless available source for the generation of fuels, chemicals and other carbon-based materials. Due to its carbon neutrality, residual biomass is being widely studied, and one of the main technologies for fuel and/or energy production are pyrolysis, gasification, or combustion [1]. Among technologies for biomass conversion, pyrolysis is widely used. It consists of a thermal decomposition process in an atmosphere without oxygen, to convert biomass into biochar, bio-oil and gases, generating no waste during the process [2]. The complexity of biomass pyrolysis arises from the difference in the decomposition of the biomass components combined with the several parameters encompassed on the pyrolysis process. The reaction mechanisms and reaction rates depend on the thermal processing conditions and reactor designs, among those the pyrolysis temperature significantly influences the distribution and properties of the productsThis work is funded by the Portuguese Foundation of Science and Technology (FCT) within the framework of the SUBe Project, ref.: PCIF/GVB/0197/2017. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CIMO (UIDB/00690/2020 and UIDP/00690/2020) and SusTEC (LA/P/0007/2021).info:eu-repo/semantics/publishedVersio

Evaluation of heating rate on the pyrolysis of residual biomass for biochar production

Biochar is a carbon-rich solid product of biomass thermal conversion, which contains several properties for a wide range of applications that promote the attention of industries and researchers. The porous structure of char particles enables its application as soil fertilizer, adsorbent, catalyst, among others [1]. In this context, biomass is a critical resource, as it can be used for biochar production at the same time produce renewable energy, being able to mitigate climate change phenomena. There are many advantages to using biomass as an energy source, namely its carbon neutrality and being a nonpolluting source. In this context, the main technologies for fuel and/or energy production from biomass are pyrolysis, gasification, or combustion [2]. Among technologies for biomass conversion, pyrolysis is widely used, consisting of a thermal decomposition process in absence of oxygen, to convert biomass into biochar, bio-oil and gases, generating no waste during the processThis work is funded by the Portuguese Foundation of Science and Technology (FCT) within the framework of the SUBe Project, ref.: PCIF/GVB/0197/2017. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CIMO (UIDB/00690/2020 and UIDP/00690/2020) and SusTEC (LA/P/0007/2021).info:eu-repo/semantics/publishedVersio

Hydrodynamic theories for a system of weakly self-interacting classical ultra-relativistic scalar particles: microscopic derivations and attractors

We derive and investigate several hydrodynamic formalisms that emerge from a system of classical, ultra-relativistic scalar particles self-interacting via a quartic potential. The specific form of the total cross-section enables the analytical computation of all transport coefficients that appear in Navier-Stokes (NS), Bemfica-Disconzi-Noronha-Kovtun (BDNK), and second-order transient hydrodynamic theories. We solve all these formalisms in a Bjorken flow scenario and show that NS and BDNK theories display unphysical features when gradients become sufficiently large. This implies that these hydrodynamic approaches may not be suitable to describe the early stages of heavy ion collisions.Comment: 30 pages, 8 figure

Hydrodynamic theories for a system of weakly self-interacting classical ultra-relativistic scalar particles: causality and stability

We investigate the causality and stability of three different relativistic dissipative fluid-dynamical formulations emerging from a system of classical, ultra-relativistic scalar particles self-interacting via a quartic potential. For this particular interaction, all transport coefficients of Navier-Stokes, Bemfica-Disconzi-Noronha-Kovtun and second-order transient theories can be computed in analytical form. We first show that Navier-Stokes theory is acausal and unstable regardless of the matching conditions. On the other hand, BDNK theory can be linearly causal and stable for a particular set of matching choices that does not contain the so-called exotic Eckart prescription. In particular, using the Li\'enard-Chipart criterion, we obtain a set of sufficient conditions that guarantee the stability of the theory. Last, second-order transient hydrodynamic theory in Landau matching is shown to be linearly causal and stable.Comment: 21 pages, 5 figure

Triad: Trusted Timestamps in Untrusted Environments

We aim to provide trusted time measurement mechanisms to applications and cloud infrastructure deployed in environments that could harbor potential adversaries, including the hardware infrastructure provider. Despite Trusted Execution Environments (TEEs) providing multiple security functionalities, timestamps from the Operating System are not covered. Nevertheless, some services require time for validating permissions or ordering events. To address that need, we introduce Triad, a trusted timestamp dispatcher of time readings. The solution provides trusted timestamps enforced by mutually supportive enclave-based clock servers that create a continuous trusted timeline. We leverage enclave properties such as forced exits and CPU-based counters to mitigate attacks on the server's timestamp counters. Triad produces trusted, confidential, monotonically-increasing timestamps with bounded error and desirable, non-trivial properties. Our implementation relies on Intel SGX and SCONE, allowing transparent usage. We evaluate Triad's error and behavior in multiple dimensions