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Convalescent plasma is used to treat COVID-19. There are theoretical concerns about the impact of pro-coagulant factors in convalescent plasma on the coagulation cascade particularly among patients with severe COVID-19. The aim of this study was to evaluate the coagulation profile of COVID-19 convalescent plasma. Clotting times and coagulation factor assays were compared between fresh frozen plasma, COVID-19 convalescent plasma, and pathogen-reduced COVID-19 convalescent plasma. Measurements included prothrombin time, activated partial thromboplastin time, thrombin time, fibrinogen, D-dimer, von Willebrand factor activity, von Willebrand factor antigen, coagulation factors II, V, VII–XII, protein S activity, protein C antigen, and alpha-2 plasmin inhibitor. Clotting times and coagulation factor assays were not different between COVID-19 convalescent plasma and fresh frozen plasma, except for protein C antigen. When compared to fresh frozen plasma and regular convalescent plasma, pathogen reduction treatment increased activated partial thromboplastin time and thrombin time, while reducing fibrinogen, coagulation factor II, V, VIII, IX, X, XI, XII, protein S activity, and alpha-2 plasmin inhibitor. The coagulation profiles of human COVID-19 convalescent plasma and standard fresh frozen plasma are not different. Pathogen reduced COVID-19 convalescent plasma is associated with reduction of coagulation factors and a slight prolongation of coagulation times, as anticipated. A key limitation of the study is that the COVID-19 disease course of the convalesced donors was not characterized. [ABSTRACT FROM AUTHOR]

Successful therapeutics and vaccines for coronavirus disease 2019 (COVID-19) have harnessed the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Evidence that SARS-CoV-2 exists as locally evolving variants suggests that immunological differences may impact the effectiveness of antibody-based treatments such as convalescent plasma and vaccines. Considering that near-sourced convalescent plasma likely reflects the antigenic composition of local viral strains, we hypothesize that convalescent plasma has a higher efficacy, as defined by death within 30 days of transfusion, when the convalescent plasma donor and treated patient were in close geographic proximity. Results of a series of modeling techniques applied to approximately 28,000 patients from the Expanded Access to Convalescent Plasma program (ClinicalTrials.gov number: NCT04338360) support this hypothesis. This work has implications for the interpretation of clinical studies, the ability to develop effective COVID-19 treatments, and, potentially, for the effectiveness of COVID-19 vaccines as additional locally-evolving variants continue to emerge. Regional differences in SARS-CoV-2 variants may affect treatment outcome. Here, the authors show that near-sourced convalescent plasma has higher efficacy, as defined by death within 30 days of transfusion, than plasma sourced more than 150 miles away. [ABSTRACT FROM AUTHOR]

Abstract Purpose The present investigation evaluated the validity and reliability of carotid-toe PWV (ctPWV) as a non-intrusive measure of systemic arterial stiffness in healthy young adults. Methods The Validity Trial examined the association and agreement between cfPWV and ctPWV in 33 adults (24 ± 2 years; 14 females), while the Reliability Trial assessed the variability in cfPWV and ctPWV in 13 adults (22 ± 2 years; 5 females) over repeat visits. Proximal pulse waves were acquired (applanation tonometry) from the left common carotid (CCA) for both measures, while distal pulse waves were acquired from the left femoral artery (applanation tonometry) and the second left toe (pulse oximeter) for cfPWV and ctPWV, respectively. Results cfPWV (5.3 ± 0.7, 3.9–6.5 m/s) and ctPWV (5.4 ± 0.5, 4.6–6.3 m/s) demonstrated a moderate-to-strong positive linear correlation (r = 0.79, P < 0.01) and a strong intra-class correlation (ICC; ICC = 0.86, P < 0.01). The Bland–Altman plot demonstrated agreement between cfPWV and ctPWV with no fixed bias (0.1 m/s, ± 2SD: −0.8 to 0.9 m/s, P > 0.05) and all data points falling within ±2 SD of the mean difference between measures. cfPWV and ctPWV demonstrated reliability across visits as evidenced by low coefficients of variation (cfPWV: 3.4 ± 2.6%, ctPWV: 2.6 ± 2.5%) and strong ICCs (cfPWV: ICC = 0.91, ctPWV: ICC = 0.84, both P < 0.01). Conclusions Through comparison with cfPWV, this study provides evidence to suggest that ctPWV yields a valid and reliable index of arterial stiffness in healthy young adults. Highlights • Carotid-toe pulse wave velocity (PWV) exhibited agreement with carotid-femoral PWV. • Carotid-toe PWV demonstrated within-subject reproducibility across days. • Carotid-toe PWV represents a valid index of arterial stiffness in healthy individuals. [ABSTRACT FROM AUTHOR]

A major aspect of the power of a historically based science story derives from its ability to cultivate interest in the reader or listener. In this paper, we review the research on interest originating from diverse scholarly areas and apply it to the understanding, construction, and effective use of science stories in both formal and informal learning environments. Significantly, the raising of interest in science addresses the vital concern of declining engagement with school science, which might be thought of as a decline in interest. Prototype stories and methods to incorporate them are included. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to discuss and apply the notion of romantic understanding by outlining its features and its potential role in science education, to identify its features in the story of Nikola Tesla, and to describe an empirical study conducted to determine the effect of telling such a story to Grade 9 students. Elaborated features of the story are the humanization of meaning, an association with heroes and heroic qualities, the limits of reality and extremes of experience, a sense of wonder, and a contesting of conventions and conventional ideas. The study demonstrates the learning benefits of encouraging a romantic understanding through a story that is structured explicitly around the identified features, in this instance in the context of the production and transmission of alternating current electricity. Quantitative and qualitative analyses of journal entries showed that the group of students who were encouraged to understand the concept of alternating current romantically (the experimental group) became more involved with both the content and the context of the story than a comparison group of students who were taught the concept explicitly, without a context (the control group). The students in the experimental group also performed statistically better on a science-content test taken 1 week and again 8 weeks after the indicated teaching intervention. This finding, along with the content analyses of students' journals, provided evidence of romantic understanding of the science content for those students who listened to the Tesla story. [ABSTRACT FROM AUTHOR]

The literature on the pedagogical aspects of the photoelectric effect as used in the undergraduate student laboratory shows that little research has been done in this area. Our current study is an analysis of the instructions in 38, electronically published laboratory manuals for the photoelectric effect. The analyses were based on history and philosophy of science criteria that we had developed for evaluating the presentation of the photoelectric effect in introductory, university-physics textbooks. The results show that writers of laboratory instructions do not pay sufficient attention to the relevant background for the photoelectric effect. In our study, none of the instructions achieved a score of excellent, only 5% were scored as satisfactory, and only 7% mentioned the various aspects contained in our criteria. These results for our analysis of laboratory instructions are significantly less favorable than those achieved for physics textbooks in our previous study. Based on our work, we recommend that several historical aspects be included in all laboratory instructions for the photoelectric effect. [ABSTRACT FROM AUTHOR]

The forest on Blue Mountain, near Lehigh Gap, has been injured by emissions from two historical zinc (Zn) smelters in Palmerton, PA, located at the northern base of the mountain. The uppermost mineral soil and lower litter from sites along a transect, just south of the ridgetop, contained from 64 to 4400 mg/kg Zn. We measured forest metrics at 15 sampling sites to ascertain how forest structure, species composition and regeneration are related to soil concentrations of Zn, the probable principal cause of the injury. Understanding how ecotoxicological injury is related to soil Zn concentrations helps us quantify the extent of injury to the ecosystem on Blue Mountain as well as to generalize to other sites. The sum of canopy closure and shrub cover, suggested as a broadly inclusive measure of forest structure, was decreased to half at approximately 2060 mg/kg Zn (102 mg/kg Sr(N0)-extractable Zn). Tree-seedling density was decreased by 80% (from 10.5/m to 2.1/m) at a much lower concentration: 1080 mg/kg Zn (59 mg/kg Sr(N0)-extractable Zn). Changes in species composition and richness were not as useful for quantifying injury to the forest. Phytotoxicity, desiccation from exposure, and a gypsy moth infestation combined to form a barren area on the ridgetop. Liming the strongly acid Hazleton soils at the sites would partially ameliorate the observed phytotoxicity and should be considered in planning restoration. [ABSTRACT FROM AUTHOR]

The photoelectric effect is commonly used as the introductory topic for the study of quantum physics. However, a literature review reveals that besides various weaknesses and errors in the presentation of the history of the photoelectric effect, textbook presentations also contain incorrect presentations of the work function and the photon concept. In this paper, I present, in story form, five key episodes of the history of the photoelectric effect that are necessary for its accurate and adequate portrayal: (a) the discovery of the photoelectric effect, (b) the characterization of and initial explanation for the photoelectric effect, (c) Einstein's revolutionary paper on the light quantum and its explanation for the photoelectric effect, and his, eventually, receiving the Nobel Prize despite not having his hypothesis accepted, (d) Millikan's experimental verification of Einstein's photoelectric equation despite not accepting Einstein's hypothesis, and (e) Compton's measurements and his theoretical explanation which produced the ultimate acceptance of Einstein's hypothesis. The story, entitled 'The Birth of the Photon Concept,' has been tested in a classroom setting and is proposed as an essential component in the process of developing sound instructional materials. [ABSTRACT FROM AUTHOR]

History of science can be used to bring scientific concepts to school science in a way that humanizes the protagonists and provides an appropriate context. The authors have researched the 1909 meeting of the British Association for the Advancement of Science (BAAS) in Winnipeg, a significant event in the city's history that has remained largely unexplored until now, despite the existence of the original documents. The Mathematics and Physical Science Division of the BAAS met in Wesley College, which is now the University of Winnipeg. The meeting took place with much fanfare and public attention, especially with the attendance of the prominent scientists Rutherford, Thomson, Hahn, and Millikan, all of whom were or would become Nobel Laureates. Prominent themes relating to this meeting will be discussed in this paper. [ABSTRACT FROM AUTHOR]

Although various reasons have been proposed to explain the potential effectiveness of science stories to promote learning, no explicit relationship of stories to learning theory in science has been propounded. In this paper, two structurally analogous models are developed and compared: a structural model of stories and a temporal conceptual change model of learning. On the basis of the similarity of the models, as elaborated, it is proposed that the structure of science stories may promote a re-enactment of the learning process, and, thereby, such stories serve to encourage active learning through the generation of hypotheses and explanations. The practical implications of this theoretical analogy can be applied to the classroom in that the utilization of stories provides the opportunity for a type of re-enactment of the learning process that may encourage both engagement with the material and the development of long-term memory structures. [ABSTRACT FROM AUTHOR]

The authors of this paper portray the perspective of Professor Leon Cooper, a theoretical physicist, Nobel laureate, active researcher, and physics textbook author, on teaching science and on the nature of science (NOS). The views presented emerged from an interview prepared by the authors and responded to in writing by Professor Cooper. Based on the gathered data and the subsequent interpretation of it, the authors identified several educational implications and drew the following conclusions: (a) science should be taught within an historical perspective; (b) textbook authors generally have an empiricist epistemology which makes their presentation of science difficult to understand; (c) an historical perspective inevitably involves comparing, contrasting, and scrutinizing different historical accounts of the same events; (d) varying interpretations of observations do not undermine the objective nature of science; (e) new ideas in physics comprise an imposed vision of the world, and these ideas are then slowly accepted by the scientific community; (f) the current view in any science is almost always a mixture of data, hypotheses, theoretical ideas, and conjectures; (g) since experiments are difficult to perform and understand, scientists rely on their presuppositions to guide the integration of data, theory, and conjectures; (h) inconsistencies in the construction of theories can facilitate new theoretical ideas; and (i) case studies based on various experiments show that scientists use intuition which is guided by facts, conjectures, and speculations. [ABSTRACT FROM AUTHOR]

The Millikan oil drop experiment has been characterized as one of the ‘most beautiful’ physics experiments of all time and, certainly, as one of the most frustrating of all the exercises in the undergraduate physics laboratory. A literature review reveals that work done on addressing student difficulties in performing the oil drop experiment has, to date, not achieved a significant measure of success. The historical background of the oil drop experiment is well established in the literature from the perspective of historians of science, but not so from the perspective of teachers and students of science. A summary of historical details surrounding the original experiment suitable for use in revising the instructional approach is presented. Both Millikan and his graduate student, Fletcher, are featured with the view to emphasizing details that humanize the protagonists and that are likely to raise student interest. The issue of the necessary reliance on presuppositions in doing speculative research is raised, both from the historical account and from the insights of university physics students who heard the historical account and performed the experiment. Difficulties current students have in performing the experiment are discussed from the perspective of Hodson (Stud Sci Educ 22:85–142, 1993) framework and the students’ own observations. Last, further historical materials are outlined that may be used to encourage student insight into the fundamental nature of electricity. It is proposed that these aspects are essential as a basis for identifying and addressing student difficulties with the Millikan oil drop experiment. [ABSTRACT FROM AUTHOR]

Science educators are beginning to establish a theoretical and methodological foundation for constructing and using stories in science teaching. At the same time, it is not clear to what degree science stories that have recently been written adhere to the guidelines that are being proposed. The author has written a story about Louis Slotin, which deals with the beginnings of radiation protection, to serve as a case study. In this paper, the story is dissected and evaluated with the view to begin to establish a method of literary criticism for science stories. In addition, student responses to the story are investigated and interpreted. [ABSTRACT FROM AUTHOR]

Science curriculum outcomes at the middle school level are typically associated with the decontextualized science found in textbooks and teacher resources. However, the typical middle years classroom with a single teacher is an ideal setting for an integrated approach to learning science in the context of social studies, language arts, art, and other subject areas. In this paper, we describe the first phase of a three-phase integrated curriculum project. The curriculum uses an historical perspective, narratives, and a student-centred approach to create materials that integrate the Grade 5 Science weather cluster with the Grade 5 Social Studies unit on the Canadian fur trade. Risk factors that contribute to inadequate science teaching and learning are identified and several protective factors that contribute to teacher efficacy are advanced. [ABSTRACT FROM AUTHOR]

Many educators today advocate the use of historical narratives as one of a number of possible contexts for teaching science. However, several pedagogical and epistemological issues arise when implementing narratives in the classroom. In this paper, we are interested in expanding our view of narrative, specific to integrating the history of science and science teaching, and we extend our argument beyond simple anecdotal references to recognise the benefits of the historical narrative in a variety of ways. At the same time, we address pedagogical concerns by broadening perceptions of the manner and contexts in which narratives can be developed so as to include imaginative and manipulative elements that provide interactive experiences for students that are more conducive to implementation by science teachers. Several practical examples are presented as illustrations of historical narratives with imaginative and manipulative elements that by design facilitate a more meaningful implementation in the science classroom. [ABSTRACT FROM AUTHOR]

The use of historically based stories to teach science has both theoretical and practical support. This paper outlines how the historically based story may be utilized effectively in the classroom and, as an illustration of this, presents the story of Lord Kelvin’s role in the laying of the first trans-Atlantic communications cable during the period from 1857 to 1866. Expected and observed classroom benefits that accrue from this approach are summarized. The paper concludes with an outline of a program of research which incorporates the development of historically based stories. [ABSTRACT FROM AUTHOR]

Our objective in this paper is to clarify the contextual approach in science education and to suggest appropriate uses of history in the science classroom from early years through post secondary education. We present a description of the variety of approaches by which teachers and educators may include the history of science in science instruction. This is followed by five sections in which historical approaches appropriate for early years, middle years, senior years, college, and university level learning are discussed. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including the teaching of chemistry, storytelling strategy in teaching electromagnetism, and the British Association for the Advancement of Science meeting in Winnipeg, Manitoba in 1909.

To ensure food security in the face of population growth, decreasing water and land for agriculture, and increasing climate variability, crop yields must increase faster than the current rates. Increased yields will require implementing novel approaches in genetic discovery and breeding. Here we demonstrate the potential of field-based high throughput phenotyping (HTP) on a large recombinant population of rice to identify genetic variation underlying important traits. We find that detecting quantitative trait loci (QTL) with HTP phenotyping is as accurate and effective as traditional labor-intensive measures of flowering time, height, biomass, grain yield, and harvest index. Genetic mapping in this population, derived from a cross of an modern cultivar (IR64) with a landrace (Aswina), identified four alleles with negative effect on grain yield that are fixed in IR64, demonstrating the potential for HTP of large populations as a strategy for the second green revolution. [ABSTRACT FROM AUTHOR]

With reciprocal rearing experiments, we tested the hypothesis that adaptive differences in host-use traits among soapberry bug populations have a genetic basis. These experiments were conducted with two host races from Florida, an 'ancestral-type' one on a native host plant species and a 'derived' one on a recently introduced plant species (colonized mainly post-1950), on whose seed crops this insect depends for growth and reproduction. Compared to the native host species, the introduced host produces larger seed crops over a much briefer annualperiod. Its seeds are also significantly higher in lipids and lower in nitrogen. The bug populations exhibit greater juvenile survivorship on their 'home' hosts; that is, the derived population survives better on seeds of the introduced host than does its ancestral-type counterpart, and vice versa. Regardless of the rearing host, populations from the introduced host lay much smaller eggs, and fecundity measures show a more complex pattern than does survivorship: the ancestral-type population produces eggs at the same rate on each host, while thederived population is less fecund on the native host and exhibits enhanced fecundity on the introduced host. These results indicate that the population differences are evolved rather than host-induced. Theyappear to be adaptive responses to host differences in the spatial and temporal distribution of seed availability and nutritional quality, and show that increased performance on the alien host has evolved with surprising speed and magnitude, with concomitant reductions in performance on the original host. [ABSTRACT FROM AUTHOR]