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Integrating Scientific Argumentation to Improve Undergraduate Writing and Learning in a Global Environmental Change Course
We present a strategy for using scientific argumentation in an early undergraduate laboratory course to teach disciplinary writing practices and to promote critical thinking, knowledge transformation, and understanding of the scientific method. The approach combines targeted writing instruction; data analysis and interpretation; formulation of a hypothesis; and construction of an argument. Students submit and receive feedback on two drafts of two different argumentation essays, providing the opportunity for guided practice. Each written argument is intended to draw on several weeks' course material, including short lectures, discussions, readings, and problem sets. Thus our aim with these writing assignments is to help students synthesize content and concepts, deepening their learning. We have found that this inquiry-based approach to writing engages students in course material, and significantly improves both writing and learning. We observed the greatest improvement among students with the lowest initial scores, suggesting that lower-achieving students benefitted disproportionately from this approach. Students have responded positively to the use of writing in the course, many stating on course evaluations that this is the first time they have received instruction in scientific writing. They have also pointed to a greater 'big-picture' understanding of the course gained through writing. We describe the course and our curriculum, and provide suggestions for implementation as well as rubrics used to evaluate problem sets and student argumentation essays.
Quantum discord is Bohr’s notion of non-mechanical disturbance introduced to counter the Einstein–Podolsky–Rosen argument
By rigorously formalizing the Einstein–Podolsky–Rosen (EPR) argument, and Bohr’s reply, one can appreciate that both arguments were technically correct. Their opposed conclusions about the completeness of quantum mechanics hinged upon an explicit difference in their criteria for when a measurement on Alice’s system can be regarded as not disturbing Bob’s system. The EPR criteria allow their conclusion–incompleteness–to be reached by establishing the physical reality of just a single observable q (not of both q and its conjugate observable p), but I show that Bohr’s definition of disturbance prevents the EPR chain of reasoning from establishing even this. Moreover, I show that Bohr’s definition is intimately related to the asymmetric concept of quantum discord from quantum information theory: if and only if the joint state has no Alice-discord, she can measure any observable without disturbing (in Bohr’s sense) Bob’s system. Discord can be present even when systems are unentangled, and this has implications for our understanding of the historical development of notions of quantum nonlocality. -- Highlights: •Both the EPR argument, and Bohr’s reply, were technically correct. •Their opposed conclusions came from different criteria for disturbance. •Bohr’s criterion works against even the simplified (one-variable) EPR argument. •Bohr’s criterion for disturbance is intimately related to quantum discord. •This illuminates the historical development of notions of quantum nonlocality.
Assessing the perception and reality of arguments against thermal waste treatment plants in terms of property prices
Highlights: • Previous research studies have shown that EfW facilities negatively impact the local house prices. • In this study property prices surrounding 3 operational EfW plants were analysed. • No significant negative effect on property prices due to an incinerator was found. - Abstract: The thermal processing of waste materials, although considered to be an essential part of waste management, is often sharply contested in the UK. Arguments such as health, depletion of resources, cost, noise, odours, traffic movement and house prices are often cited as reasons against the development of such facilities. This study aims to review the arguments and identify any effect on property prices due to the public perception of the plant. A selection of existing energy from waste (EfW) facilities in the UK, operational for at least 7 years, was selected and property sales data, within 5 km of the sites, was acquired and analysed in detail. The locations of the properties were calculated in relation to the plant using GIS software (ArcGIS) and the distances split into 5 zones ranging from 0 to 5 km from the site. The local property sale prices, normalised against the local house price index, were compared in two time periods, before and after the facility became operational, across each of the 5 zones. In all cases analysed no significant negative effect was observed on property prices at any distance within 5 km from a modern operational incinerator. This indicated that the perceived negative effect of the thermal processing of waste on local property values is negligible.
Charge density waves in disordered media circumventing the Imry-Ma argument
Two powerful theoretical predictions, Anderson localization and the Imry-Ma argument, impose significant restrictions on the phases of matter that can exist in the presence of even the smallest amount of disorder in one-dimensional systems. These predictions forbid electrically conducting states and ordered states respectively. It was thus remarkable that a mechanism to circumvent Anderson localization relying on the presence of correlated disorder was found, that is also realized in certain biomolecular systems. Here, in a similar manner, we show that the Imry-Ma argument can be circumvented, resulting in the formation of stable ordered states with discrete broken symmetries in disordered one dimensional systems. We then investigate other mechanisms by which disorder can destroy an ordered state.
Connections between Student Explanations and Arguments from Evidence about Plant Growth
We investigate how students connect explanations and arguments from evidence about plant growth and metabolism—two key practices described by the Next Generation Science Standards. This study reports analyses of interviews with 22 middle and high school students postinstruction, focusing on how their sense-making strategies led them to interpret—or misinterpret—scientific explanations and arguments from evidence. The principles of conservation of matter and energy can provide a framework for making sense of phenomena, but our results show that some students reasoned about plant growth as an action enabled by water, air, sunlight, and soil rather than a process of matter and energy transformation. These students reinterpreted the hypotheses and results of standard investigations of plant growth, such as van Helmont's experiment, to match their own understanding of how plants grow. Only the more advanced students consistently interpreted mass changes in plants or soil as evidence of movement of matter. We also observed that a higher degree of scaffolding during some of the interview questions allowed mid-level students to improve their responses. We describe our progress and challenges developing teaching materials with scaffolding to improve students’ understanding of plant growth and metabolism.
Persuasive Influence Detection: The Role of Argument Sequencing
Automatic detection of persuasion in online discussion is key to understanding how social media is used. Predicting persuasiveness is difficult, however, due to the need to model world knowledge, dialogue, and sequential reasoning. Here, we focus on modeling the sequence of arguments in social media posts using neural models with embeddings for words, discourse relations, and semantic frames. We demonstrate significant improvement over prior work in detecting successful arguments. We also present an error analysis assessing novice human performance at predicting persuasiveness.
Hazard Categorization Reduction via Nature of the Process Argument
This paper documents the Hazard Categorization (HC) and Critical Safety Evaluation (CSE) for activities performed using an Inspection Object (IO) in excess of the single parameter subcritical limit of 700 g of U-235. By virtue of exceeding the single parameter subcritical limit and the subsequent potential for criticality, the IO HC is initially categorized as HC2. However, a novel application of the nature of the process argument was employed to reduce the IO HC from HC2 to less than HC3 (LTHC3). The IO is composed of five separate uranium metal plates that total no greater than 3.82 kg of U-235 (U(20)). The IO is planned to be arranged in various configurations. As the IO serves as a standard for experimentation aimed at establishing techniques for detection of fissionable materials, it may be placed in close proximity to various reflectors, moderators, or both. The most reactive configurations of the IO were systematically evaluated and shown that despite the mass of U-235 and potential positioning near various reflectors and moderators, the IO cannot be assembled into a critical configuration. Therefore, the potential for criticality does not exist. With Department of Energy approval, a Hazards Assessment Document with high-level (facility-level) controls on the plates negates the potential for criticality and satisfies the nature of the process argument to reduce the HC from HC2 to LTHC3.
A non-perturbative argument for the non-abelian Higgs mechanism
The evasion of massless Goldstone bosons by the non-abelian Higgs mechanism is proved by a non-perturbative argument in the local BRST gauge. -- Highlights: •The perturbative explanation of the Higgs mechanism (HM) is not under mathematical control. •We offer a non-perturbative proof of the absence of Goldstone bosons from the non-abelian HM. •Our non-perturbative proof in the BRST gauge avoids a mean field ansatz and expansion.
Local Group timing argument and virial theorem mass estimators from cosmological simulations
ABSTRACT We identify Local Group (LG) analogues in the IllustrisTNG cosmological simulation, and use these to study two-mass estimators for the LG: One based on the timing argument (TA) and one based on the virial theorem (VT). Including updated measurements of the Milky Way-M31 tangential velocity and the cosmological constant, we show that the TA mass estimator slightly overestimates the true median LG-mass, though the ratio of the TA to the true mass is consistent at the approximate 90 per cent c.l.. These are in broad agreement with previous results using dark matter-only simulations. We show that the VT estimator better estimates the true LG-mass, though there is a larger scatter in the virial mass to true mass ratio relative to the corresponding ratio for the TA. We attribute the broader scatter in the VT estimator to several factors, including the predominantly radial orbits for LG satellite galaxies, which differs from the VT assumption of isotropic orbits. With the systematic uncertainties we derive, the updated measurements of the LG mass at 90 per cent c.l. are $4.75_{-2.41}^{+2.22} \times 10^{12}$ M⊙ from the TA and $2.0_{-1.5}^{+2.1} \times 10^{12}$ M⊙ from the VT. We consider the LMC’s effect on the TA and VT LG mass estimates, and do not find exact LMC–MW–M31 analogues in the Illustris simulations. However, in LG simulations with satellite companions as massive as the LMC, we find that the effect on the TA and VT estimators is small, though we need further studies on a larger sample of LMC–MW–M31 systems to confirm these results.
RECONCILING AGN-STAR FORMATION, THE SOLTAN ARGUMENT, AND MEIER’S PARADOX
We provide a theoretical context for understanding the recent work of Kalfountzou et al. showing that star formation is enhanced at lower optical luminosity in radio-loud quasars. Our proposal for coupling the assumption of collimated FRII quasar-jet-induced star formation with lower accretion optical luminosity also explains the observed jet power peak in active galaxies at higher redshift compared to the peak in accretion power, doing so in a way that predicts the existence of a family of radio-quiet active galactic nuclei associated with rapidly spinning supermassive black holes at low redshift, as mounting observations suggest. The relevance of this work lies in its promise to explain the observed cosmological evolution of accretion power, jet power, and star formation in a way that is both compatible with the Soltan argument and resolves the so-called “Meier Paradox.”.
An argument for using anaerobes as microbial cell factories to advance synthetic biology and biomanufacturing
Anaerobes thrive in the absence of oxygen and are an untapped reservoir of biotechnological potential. Therefore, bioprospecting efforts focused on anaerobic microbial diversity could rapidly uncover new enzymes, pathways, and chassis organisms to drive biotechnology innovation. Despite their potential utility, anaerobic fermenters are viewed as inefficient from a biochemical perspective because their metabolisms produce fewer ATP (~2) per molecule of glucose processed than heterotrophic respirers (~32–38 ATP). While aerobes excel at ATP generation, they are often less efficient than anaerobes at processes that compete with ATP generation for cellular resources. This perspective highlights how anaerobic adaptations are advantageous for synthetic biology and biomanufacturing applications through the engineering of microbial cell factories. We further highlight emerging applications of anaerobic bioprocessing, including the use of anaerobic metabolisms for lignocellulosic bioprocessing, human and environmental health, and value-added bioproduction.
May reversible water uptake/release by hydrates explain the thermal expansion of cement paste? ÔÇö Arguments from an inverse multiscale analysis
Quasi-instantaneous thermal expansion of cement pastes is governed by the relative humidity (RH) within their air-filled pores and by the decrease/increase of this internal RH resulting from a temperature decrease/increase. The latter effect is traced back to quasi-instantaneous water uptake/release by cement hydrates, using microporomechanics and a three-scale representation of mature cement pastes. Partially saturated gel and capillary pores are considered to be connected and spherical, with radii following exponential distributions. The Mori-Tanaka scheme provides the scale transition from effective pore pressures to eigenstrains at the cement paste level. This modeling approach, together with considering mass conservation of water, allows for downscaling macroscopic thermal expansion coefficients, so as to identify the molecular water uptake/release characteristics of the hydrates. The latter characteristics are mixture-independent, as shown by their use for predicting the thermal expansion coefficients of different mature cement pastes, with w/c-ratios ranging from 0.50 to 0.70.
What Is the Optimal Treatment of Large Brain Metastases? An Argument for a Multidisciplinary Approach
Purpose: Single-modality treatment of large brain metastases (>2 cm) with whole-brain irradiation, stereotactic radiosurgery (SRS) alone, or surgery alone is not effective, with local failure (LF) rates of 50% to 90%. Our goal was to improve local control (LC) by using multimodality therapy of surgery and adjuvant SRS targeting the resection cavity. Patients and Methods: We retrospectively evaluated 97 patients with brain metastases >2 cm in diameter treated with surgery and cavity SRS. Local and distant brain failure (DF) rates were analyzed with competing risk analysis, with death as a competing risk. The overall survival rate was calculated by the Kaplain-Meier product-limit method. Results: The median imaging follow-up duration for all patients was 10 months (range, 1-80 months). The 12-month cumulative incidence rates of LF, with death as a competing risk, were 9.3% (95% confidence interval [CI], 4.5%-16.1%), and the median time to LF was 6 months (range, 3-17 months). The 12-month cumulative incidence rate of DF, with death as a competing risk, was 53% (95% CI, 43%-63%). The median survival time for all patients was 15.6 months. The median survival times for recursive partitioning analysis classes 1, 2, and 3 were 33.8, 13.7, and 9.0 months, respectively (p = 0.022). On multivariate analysis, Karnofsky Performance Status ({>=}80 vs. <80; hazard ratio 0.54; 95% CI 0.31-0.94; p = 0.029) and maximum preoperative tumor diameter (hazard ratio 1.41; 95% CI 1.08-1.85; p = 0.013) were associated with survival. Five patients (5%) required intervention for Common Terminology Criteria for Adverse Events v4.02 grade 2 and 3 toxicity. Conclusion: Surgery and adjuvant resection cavity SRS yields excellent LC of large brain metastases. Compared with other multimodality treatment options, this approach allows patients to avoid or delay whole-brain irradiation without compromising LC.
A simple argument that small hydrogen may exist
This paper discusses a possible existence of small hydrogen, which may have been created during the Big Bang before formation of normal hydrogen.
Scaling arguments for a plasma experiment relevant to an interplanetary coronal mass ejection
We present the design of a plasma experiment scaled to be relevant to an interplanetary coronal mass ejection (ICME) traveling from the Sun to the Earth. The experiment would launch a compact torus of plasma (the scaled analog of the coronal mass ejected by the Sun) into a magnetized background plasma (the scaled analog of the interplanetary medium, the diffuse magnetized plasma that fills the Solar System). We present the complete process of scaling the ICME system to a laboratory experiment: beginning with the ICME features that we aim to replicate with a laboratory experiment, explaining how these desired features are translated into specific design constraints, and presenting a set of experimental parameters that meet those constraints. We find that the experiment would be possible with plasma conditions typically achieved in large-scale facilities such as the Big Red Ball at the University of Wisconsin or the LArge Plasma Device at the University of California, Los Angeles.
An argument for weakly magnetized, slowly rotating progenitors of long gamma-ray bursts
Using binary evolution with Case-C mass transfer, the spins of several black holes (BHs) in X-ray binaries (XBs) have been predicted and confirmed (three cases) by observations. The rotational energy of these BHs is sufficient to power up long gamma-ray bursts (GRBs) and hypernovae (HNe) and still leave a Kerr BH behind. However, strong magnetic fields and/or dynamo effects in the interior of such stars deplete their cores from angular momentum preventing the formation of collapsars. Thus, even though binaries can produce Kerr BHs, most of their rotation is acquired from the stellar mantle, with a long delay between BH formation and spin up. Such binaries would not form GRBs. We study whether the conditions required to produce GRBs can be met by the progenitors of such BHs. Tidal-synchronization and Alfvén timescales are compared for magnetic fields of different intensities threading He stars. A search is made for a magnetic field range that allows tidal spin up all the way in to the stellar core but prevents its slow down during differential rotation phases. The energetics for producing a strong magnetic field during core collapse, which may allow for a GRB central engine, are also estimated. An observationally reasonable choice of parameters is found (B ≲ 10{sup 2} G threading a slowly rotating He star) that allows Fe cores to retain substantial angular momentum. Thus, the Case-C mass-transfer binary channel is capable of explaining long GRBs. However, the progenitors must have low initial spin and low internal magnetic field throughout their H-burning and He-burning phases.