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This paper deals with the joint construction of knowledge by the teacher and the students in a physics classroom. It is focused on the status of epistemic certainty/uncertainty of knowledge. The same element of knowledge can be introduced as possible and thus uncertain and then evolve towards a status of epistemic certainty; the status of other elements can do the reverse. The evolution of a certainty/uncertainty status reflects the evolution of the shared knowledge in the classroom. The study of this evolution is based on a previous analysis of the evolution of knowledge in a classroom during a teaching sequence of mechanics at grade 10. From this analysis two notions were selected and the evolution of the elements of knowledge associated was analyzed in terms of epistemic certainty/uncertainty. The results show how the emergence of new epistemic questions depends on the nature and status of student's prior knowledge; in other terms, new epistemic uncertainty emerges from epistemic certainty.

Despite successful introduction of NK-based cellular therapy in the treatment of myeloid leukemia, the potential use of NK alloreactivity in solid malignancies is still elusive. We performed a phase I clinical trial to assess the safety and efficacy of in situ delivery of allogeneic NK cells combined with cetuximab in liver metastasis of gastrointestinal origin. The conditioning chemotherapy was administrated before the allogeneic NK cells injection via hepatic artery. Three escalating doses were tested (3.106, 8.106 and 12.106 NK cells/kg) following by a high-dose interleukin-2 (IL-2). Cetuximab was administered intravenously every week for 7 weeks. Nine patients with liver metastases of colorectal or pancreatic cancers were included, three per dose level. Hepatic artery injection was successfully performed in all patients with no report of dose-limiting toxicity. Two patients had febrile aplasia requiring a short-term antibiotherapy. Grade 3/4 anemia and thrombopenia were also observed related to the chemotherapy. Objective clinical responses were documented in 3 patients and among them 2 occurred in patients injected with cell products harboring two KIR ligand mismatches and one in a patient with one KIR ligand mismatch. Immune monitoring revealed that most patients presented an increase but transient of IL-15 and IL-7 cytokines levels one week after chemotherapy. Furthermore, a high expansion of FoxP3+regulatory T cells and PD-1+ T cells was observed in all patients, related to IL-2 administration. Our results demonstrated that combining allogeneic NK cells transfer via intra-hepatic artery, cetuximab and a high-dose IL-2 is feasible, well tolerated and may result in clinical responses.

Bronchiolitis obliterans syndrome (BOS), the main manifestation of chronic lung allograft dysfunction, leads to poor long-term survival after lung transplantation. Identifying predictors of BOS is essential to prevent the progression of dysfunction before irreversible damage occurs. By using a large set of 107 samples from lung recipients, we performed microarray gene expression profiling of whole blood to identify early biomarkers of BOS, including samples from 49 patients with stable function for at least 3 years, 32 samples collected at least 6 months before BOS diagnosis (prediction group), and 26 samples at or after BOS diagnosis (diagnosis group). An independent set from 25 lung recipients was used for validation by quantitative PCR (13 stables, 11 in the prediction group, and 8 in the diagnosis group). We identified 50 transcripts differentially expressed between stable and BOS recipients. Three genes, namely POU class 2 associating factor 1 (POU2AF1), T-cell leukemia/lymphoma protein 1A (TCL1A), and B cell lymphocyte kinase, were validated as predictive biomarkers of BOS more than 6 months before diagnosis, with areas under the curve of 0.83, 0.77, and 0.78 respectively. These genes allow stratification based on BOS risk (log-rank test p

The present study investigated the impact of study-test similarity on face recognition by manipulating, in the same experiment, the expression change (same vs. different) and the task-processing context (inclusion vs. exclusion instructions) as within-subject variables. Consistent with the dual-process framework, the present results showed that participants performed better on the inclusion task than on the exclusion task, with no response bias. A mid-frontal FN400 old/new effect and a parietal old/new effect were found in both tasks. However, modulations of the ERP old/new effects generated by the expression change on recognized faces differed across tasks. The modulations of the ERP old/new effects were proportional to the degree of matching between the study face and the recognition face in the inclusion task, but not in the exclusion task. The observed modulation of the FN400 old/new effect by the task instructions when familiarity and conceptual priming were kept constant indicates that these early ERP correlates of recognition depend on voluntary task-related control. The present results question the idea that FN400 reflects implicit memory processes such as conceptual priming and show that the extent to which the FN400 discriminates between conditions depends on the retrieval orientation at test. They are discussed in relation to recent controversies about the ERP correlates of familiarity in face recognition. This study suggests that while both conceptual and perceptual information can contribute to the familiarity signal reflected by the FN400 effect, their relative contributions vary with the task demands. (Contains 3 tables and 3 figures.)

In this paper, we account for a way of modeling classroom practices from a didactic point of view in the case of the teaching of physics. Then we draw certain proposals for a comparative analysis of school practices. Our modeling is based on a pragmatic approach of classroom practices. In a first step, the Theory of joint action in didactics is succinctly introduced in connection with several other theoretical choices concerning learning, knowledge and the necessity of different temporal scales. In a second step, the methodological tools of modeling are introduced with some examples of analyzes that illustrate the links between theoretical framework and methodological tools. These tools are aligned with certain research questions related to classroom practices. Two types of tools are proposed: one, at the mesoscopic level, allows to structure a series of sessions of a teaching sequence; the other, at the microscopic level, allows to analyze the pieces of knowledge at stake in the classroom discourses. In the conclusion, we draw some proposals for a comparative analysis based on the theoretical and methodological framework presented, in particular the comparison of time scales and units of analysis at the meso and microscopic level.

During Dec-2013, a chikungunya virus (CHIKV) outbreak was first detected in the French-West Indies. Subsequently, the virus dispersed to other Caribbean islands, continental America and many islands in the Pacific Ocean. Previous estimates of the attack rate were based on declaration of clinically suspected cases.Individual testing for CHIKV RNA of all (n = 16,386) blood donations between Feb-24th 2014 and Jan-31st 2015 identified 0·36% and 0·42% of positives in Guadeloupe and Martinique, respectively. The incidence curves faithfully correlated with those of suspected clinical cases in the general population of Guadeloupe (abrupt epidemic peak), but not in Martinique (flatter epidemic growth). No significant relationship was identified between CHIKV RNA detection and age-classes or blood groups. Prospective (Feb-2014 to Jan-2015; n = 9,506) and retrospective (Aug-2013 to Feb-2014; n = 6,559) seroepidemiological surveys in blood donors identified a final seroprevalence of 48·1% in Guadeloupe and 41·9% in Martinique. Retrospective survey also suggested the absence or limited "silent" CHIKV circulation before the outbreak. Parameters associated with increased seroprevalence were: Gender (M>F), KEL-1, [RH+1/KEL-1], [A/RH+1] and [A/RH+1/KEL-1] blood groups in Martiniquan donors. A simulation model based on observed incidence and actual seroprevalence values predicted 2·5 and 2·3 days of asymptomatic viraemia in Martiniquan and Guadeloupian blood donors respectively.This study, implemented promptly with relatively limited logistical requirements during CHIKV emergence in the Caribbean, provided unique information regarding retrospective and prospective epidemiology, infection risk factors and natural history of the disease. In the stressful context of emerging infectious disease outbreaks, blood donor-based studies can serve as robust and cost-effective first-line tools for public health surveys.

In literature, several processes have been suggested to describe conceptual changes being undertaken. However, a few parts of studies analyse in great detail which students' learning processes are involved in physics classes during teaching, and how they are used. Following a socio-constructivist approach using tools coming from discourse analysis, we suggest studying three processes of students' learning: (1) establishing links between ideas, (2) increasing the domain of applicability of ideas, or (3) decreasing the domain of applicability of ideas. Our database consists of video data and written worksheets of two students at the upper-secondary school level (Grade 10 [15-year-old students]) during a one-month teaching sequence about gas. Based on semiotic resources contained in oral and written language, we reconstruct in great detail all the ideas about gas expressed by both students during the entire teaching sequence. Our analysis deals with (1) how learning processes are identified based on the ideas expressed by students, and (2) how the three learning processes are used by the two students during teaching. Our results show that during the teaching sequence: (1) the emergence of the networks of three ideas is supported by networks of two ideas expressed previously by students; (2) both students express more networks of two ideas than networks of three ideas; (3) the process "increasing the domain of applicability" of an idea or a network of ideas is very often involved; and (4) the process "decreasing the domain of applicability" of an idea or network of ideas is rarely used by them. (Contains 10 figures, 3 tables, and 3 notes.)

We screened plasma samples (minipools of 96 samples, corresponding to 53,234 blood donations) from France that had been processed with solvent–detergent for hepatitis E virus RNA. The detection rate was 1 HEV-positive sample/2,218 blood donations. Most samples (22/24) from viremic donors were negative for IgG and IgM against HEV.

Introduction: Adopting a conceptual change perspective yields information not only about the organization of students' conceptions and the mechanisms behind their changes, but also about the most effective teaching interventions for promoting conceptual change. In experimental science, modelling constitutes a basic activity for acquiring and using scientific concepts, and a key method for eliciting conceptual change. The aim of this study was to investigate how modelling activities can elicit conceptual changes concerning the notion of energy. Method: 40 students aged 16-17 years, working in pairs had to construct symbolic representations of three materially present experiments ("Battery-bulb", "Falling object" and "Rising object") drawing on a simple model that introduced them to the properties of energy. In order to track changes in their cognitive processes, we defined a number of specific modelling categories. Results: Results showed that students implemented increasingly complex cognitive processes to solve the three problems. Modelling activities enhance the ability to process the material world and the world of theories and models simultaneously, even when there is no isomorphism between the two. Discussion: The modelling activities we administered to students promoted efficient learning, insofar as the conceptual change mechanism was put in place. Solving the three problems allowed students to draw on their prior knowledge but also to develop new knowledge about the material and theoretical worlds. They acquired the ability to process representations simultaneously from concrete and conceptual worlds and to move freely between them, despite their lack of isomorphism. (Contains 1 figure and 4 tables.)

Design-based research, and particularly its theoretical status, is a subject of debate in the science education community. In the first part of this paper, a theoretical framework drawn up to develop design-based research will be presented. This framework is mainly based on epistemological analysis of physics modelling, learning and teaching hypotheses. It includes grand theories, a specific theory that following Cobb, Confrey, diSessa, Lehrer, and Schauble is a "humble theory" in the sense that it does "real work", and tools for design. In the second part, we will show how this specific theory and its tools led designers to develop teaching resources in the case of a teaching sequence on mechanics (Grade 10). We will explain how the components of the specific theory and tools guide the design at different levels; the conceptual structure of the teaching sequence, the chronology of the activities, the various choices of the type of activity and their wording. This presentation makes the bases of designing teaching resources explicit and therefore allows for scientific debate. (Contains 15 figures, 2 tables, and 3 notes.)

This commentary on Roth, Lee, and Hwang's paper aims at analysing their theoretical approach in terms of its object of study, and the aspects that are brought to the fore, like the cultural activity of conversation, and those that are overshadowed, like the role of the material world and its perception on learning. This analysis, developed on the basis of a pragmatic approach that combines theoretical frameworks, leads to a debate about the relevant components of teaching-learning situations according to the theoretical approaches, and the extent to which, due to the complexity of the studied phenomena, some theoretical frameworks are complementary or concurrent.

O ensaio coloca várias interrogações sobre as relações entre arte e cartografia examinando procedimentos cartográficos em mapas de artistas contemporâneos. Ao investigar as regiões efêmeras e intersticiais nos mapas, o artista cartógrafo se interessa pela inadequação intrínseca à cartografia, dada pela impossibilidade de coincidência entre os mapas e seus objetos de representação. Seus mapas revelam o processo de fabricação imaginária próprio à cartografia em espaços usados e atuais.

This article challenges three predominant narratives on educational globalization--"educational restructuring," "educational institutionalism," and "educational multilateralism"--and shows how they have largely failed to propose alternatives to the neoliberal order. I connect two disparate literatures--on educational globalization and anti-globalization social movements--to argue that the alternative globalization movement performs global citizenship education through critical pedagogy, cognitive justice, and decolonizing methodologies. To arrive at a multi-layered model of citizenship, what is needed is not only critical pedagogy, but a fundamental critique of the cognitive injustice inherent within the hegemonic neoliberal ideology by re-asserting the diversity of value systems and restoring subjugated knowledges through alternative methodologies. Drawing upon my participant observation at the 2003 anti-G8 Summit in France and anti-World Trade Organization meeting in Mexico, as well as the fourth World Social Forum in India, I propose a new research program on global educational justice. (Contains 2 tables and 17 notes.)

This contribution presents a tool elaborated from a theoretical framework linking epistemological, learning and didactical hypotheses. This framework lead to design teaching sequences from a socio-constructivist perspective, and is based on the role of models in physics or chemistry, and on the role of students' initial knowledge in learning processes. This tool, formatted as a 'grid', is applied to one example in physics (optics, grade 11), and to one example in chemistry (conductivity, grade 11). Both these examples are taken from the important activity our team has developed from several years, in collaboration with upper secondary school science teachers, in order to design teaching sequences and experiment them in real classrooms.

Currently in France, there is an evolution of the teaching theme of energy that takes greater account of society debates. This affects the disciplinary knowledge and situations involved in teaching, and raises questions about how theorizing the design of resources. The design theory developed in the case of disciplinary teaching, around the triangle Knowing-Teaching-Learning, must be adapted. The social background of the theme led us to consider non-disciplinary knowledge, to transpose the general issues into more specific questions then into situations to be studied. The article presents theoretical design tools for the "energy challenge". The analysis of the theme allows us to offer a teaching sequence aimed at reconciling society issues and learning.

Este estudio de caso se sitúa en el ámbito de la formación inicial de maestros. Examina cómo profesores de física-química analizan extractos de videos de alumnos, grabadas en una clase durante una actividad de investigación científica. Los extractos seleccionados para esta formación permiten estudiar los conocimientospuestos en práctica por los alumnos y el desarrollo de diferentes fases de su razonamiento.Los datos analizados para este estudio se sacaron durante una sesión de formacióny los constituyen grabaciones videos de dos equipos de dos profesores así como su producción escrita. Los resultados de este estudio permiten seguir la evolución de la postura de sendos profesores y muestran una evolución global de ésta al pasar de la evaluación al análisis y la comprensión de los intercambios entre los alumnos

Describes the results of a study on the similarities and differences in laboratory tasks used in science education at upper secondary school and university level in the three main science subjects in seven European countries. Some differences are noted between the science subjects and educational levels, but the dominant impression of the analysis is of similarity across educational levels, science subjects, and countries. (Author/MM)

Analyzes the evolution of the French physics curricula and experiments from the beginning of the century to the present. Shows the strong coherence of the aspects of energy presented through teaching content and experiments. (DDR)

Discusses the articulation between teaching and learning, how to differentiate them, and how to establish relations between them as it pertains to aspects of knowledge. Aims to develop teaching situations more relevant to learning. Teaching is associated with knowledge to be taught, knowledge sequencing, and teaching situations. Learning is characterized by stages and learners' cognitive processes. Contains 38 references. (Author/PVD)

Compares collaborative problem solving by learners sitting side-by-side with computer-mediated learning at a distance. Three aspects are studied: high school students' problem- solving strategies and interpretation of the teaching situation; their use of components of the situation; and the cognitive processes involved in understanding domain knowledge, energy in physics. (Author/LRW)

• Systematic review of the impact of plasma donation frequency on donor health. • Data from 4 observational and 2 experimental studies were included. • Very high-frequency donation (twice per week) may decrease IgG and ferritin levels. • Conclusions are hindered by small sample sizes and methodological limitations. • Additional high-quality studies are needed to determine a safe donation frequency threshold. Most plasma used for manufacturing plasma-derived medicinal products (PDMPs) such as albumin, immunoglobulin (Ig), and clotting factors is obtained from source plasma collected via plasmapheresis, the majority of which is contributed by the United States (US). While the demand for PDMPs continues to rise, it remains unclear whether high-frequency plasmapheresis, such as the twice-weekly plasma donation allowed in the US, may have any (long-term) adverse health effects on the donor. To investigate the frequency at which plasma can be donated without harm to the donor, the current systematic review explores the impact of plasma donation frequency on cardiovascular health, protein depletion, and adverse events in healthy plasma donors. We asked the following research question: What is the impact of plasmapheresis frequency (Intervention) on the safety or health (Outcome) of healthy donors (Population)? Six databases (PubMed, Embase, Web of Science, CINAHL, the Cochrane Library, and Transfusion Evidence Library), 2 clinical trial registries (ICTRP and clinicaltrials.gov), and the PROSPERO database were searched. Four observational and 2 experimental studies were included. The results showed that very high-frequency donation (twice per week) may result in a clinically relevant decrease in ferritin and bring IgG levels below the lower threshold of 6 g/l. However, the evidence is of low to very low certainty, and solid conclusions are hindered by the healthy donor effect and methodological limitations of the included studies. To determine a safe threshold donation frequency that minimizes any possible harmful effect on the donor, more high-quality prospective cohort studies and experimental studies are needed. We should expedite such studies to support recommendations, as conclusive evidence confirming or refuting the safety of maximum allowed donation frequencies is lacking. Donor protection is essential, given that healthy donors receive no direct medical benefit from donating plasma. [ABSTRACT FROM AUTHOR]

Thiosuccinimide-linked antibody-drug conjugates (ADCs) are susceptible to drug loss over time due to a retro-Michael reaction, which can be prevented by selecting stable conjugation positions or hydrolysis of the thiosuccinimide. Here, we investigate pyrrolobenzodiazepine (PBD) ADC drug-linkers equipped with N-phenyl maleimide functionality for stable thiol conjugation via thiosuccinimide hydrolysis. Two PBD drug-linker formats (enzyme-cleavable and non-cleavable) were evaluated following site-specific conjugation to an engineered cysteine incorporated at position T289, which is known to be unstable for N-alkyl maleimide conjugates. N-phenyl maleimide PBDs conjugated to antibodies with similar efficiencies as N-alkyl maleimide PBDs and enhanced thiosuccinimide hydrolysis for N-phenyl maleimide PBDs was confirmed by mass spectrometry, capillary isoelectric focusing, and a SYPRO Orange dye binding assay. All of the PBD ADCs were highly potent in vitro regardless of maleimide- or linker-type, exhibiting low pM EC50 values. Thiol conjugation to N-phenyl maleimide PBD minimized the retro-Michael reaction in both rat and mouse serum. However, cleavage of the valine-alanine dipeptide in mouse serum for ADCs containing cleavable drug-linker led to drug loss regardless of maleimide type, which impacted ADC potency in tumor growth inhibition studies that were conducted in mouse models. Therapeutic improvement in mouse tumor models was realized for ADCs prepared with non-cleavable PBD drug-linkers that were conjugated through N-phenyl maleimide, where a stronger tumor growth inhibition (TGI) response was achieved when compared to the analogous N-alkyl maleimide drug-linker ADC. Altogether, our findings highlight the stability and efficacy benefits of N-phenyl maleimide functionality for ADCs that are produced with thiol-maleimide conjugation chemistry.

Kazakhstan is the location of some of the most important Gulag heritage from the Soviet period of domination. However, commemoration, conservation and interpretation of Gulag sites is at best partial, visitation low and the attitude to this element of Kazakh history is ambiguous. This paper considers key heritage sites and museums in Kazakhstan and a qualitative case study approach is adopted based on a combination of interviews with twenty-four key stakeholders involved in the development and operation of Gulag tourism. Direct observations and qualitative document analysis of the major national Gulag museums and other important Gulag heritage sites was also undertaken. This research questions the orthodoxy inherent in the supposed attraction of dark tourism sites and seeks to ascertain why domestic and international visitation remains low given the scale and importance of the Gulag narrative. [ABSTRACT FROM AUTHOR]

Relevant aspects in the advances in transfusion medicine using gene therapy are related in this report.