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This article discusses student difficulties in grasping concepts from linear algebra. Using an example from an interview with a student, we propose changes that might positively impact student understanding of concepts within a problem-solving context. In particular, we illustrate barriers to student understanding and suggest technological interventions to address these barriers. [ABSTRACT FROM PUBLISHER]

Our purpose in this paper is to report on an observational study to show how students think about the links between the graph of a derived function and the original function from which it was formed. The participants were asked to perform the following task: they were presented with four graphs that represented derived functions and from these graphs they were asked to construct the original functions from which they were formed. The students then had to walk these graphs as if they were displacement–time graphs. Their discussions were recorded on audio tape and their walks were captured using data logging equipment and these were analysed together with their pencil and paper notes. From these three sources of data, we were able to construct a picture of the students’ graphical understanding of connections in calculus. The results confirm that at the start of the activity the students demonstrate an algebraic symbolic view of calculus and find it difficult to make connections between the graphs of a derived function and the function itself. By being able to ‘walk’ an associated displacement time graph, we propose that the students are extending their understanding of calculus concepts from symbolic representation to a graphical representation and to what we term a ‘physical feel’. [Copyright &y& Elsevier]

Explores the impression of mathematics and mathematician on middle school students in the United States. Concern of mathematics teachers to the impressions of students; Necessity for an increased knowledge of teachers to the role of mathematicians; Conduct of research on the Internet.

This paper describes a research project that had two goals: (1) to design and develop a tool with which to investigate pupils' images of mathematicians; and (2) to use the device to compare those images held by lower secondary pupils (ages 12–13) in five countries. We report that with small cultural differences certain stereotypical images of mathematicians are common to pupils in all of these countries and these images indicate that for pupils of this age mathematicians and the work that they do are, for all practical purposes, invisible. [ABSTRACT FROM AUTHOR]

Abstract: Background: This article examines the incidence of venous thromboembolism (VTE) in combat wounded, identifies risk factors for pulmonary embolism (PE), and compares the rate of PE in combat with previously reported civilian data. Methods: A retrospective review was performed of all U.S. military combat casualties in Operation Enduring Freedom and Operation Iraqi Freedom with a VTE recorded in the Department of Defense Trauma Registry from September 2001 to July 2011. The Military Amputation Database of all U.S. military amputations during the same 10-y period was also reviewed. Demographic data, injury characteristics, and outcomes were evaluated. Results: Among 26,634 subjects, 587 (2.2%) had a VTE. This number included 270 subjects (1.0%) with deep venous thrombosis (DVT), 223 (0.8%) with PE, and 94 (0.4%) with both DVT and PE. Lower extremity amputation was independently associated with PE (odds ratio [OR], 1.70; 95% confidence interval [CI], 1.07–2.69). A total of 1003 subjects suffered a lower extremity amputation, with 174 (17%) having a VTE. Of these, 75 subjects (7.5%) were having DVT, 70 (7.0%) were having PE, and 29 (2.9%) were found to have both a DVT and a PE. Risk factors found to be independently associated with VTE in amputees were multiple amputations (OR, 2; 95% CI, 1.35–3.42) and above the knee amputation (OR, 2.11; 95% CI, 1.3–3.32). Conclusions: Combat wounded are at a high risk for thromboembolic complications with the highest risk associated with multiple or above the knee amputations. [Copyright &y& Elsevier]

This article examines the connections of linear algebra concepts in a first course at the undergraduate level. The theoretical underpinnings of this study are grounded in the constructivist perspective (including social constructivism), Vernaud's theory of conceptual fields and Pirie and Kieren's model for the growth of mathematical understanding. In addition to the existing techniques for analysing concept maps, two new techniques are developed for analysing qualitative data based on student-constructed concept maps: (1) temporal clumping of concepts and (2) the use of adjacency matrices of an undirected graph representation of the concept map. Findings suggest that students may find it more difficult to make connections between concepts like eigenvalues and eigenvectors and concepts from other parts of the conceptual field such as basis and dimension. In fact, eigenvalues and eigenvectors seemed to be the most disconnected concepts within all of the students' concept maps. In addition, the relationships between link types and certain clumps are suggested as well as directions for future study and curriculum design. [ABSTRACT FROM AUTHOR]

Background: E39, an HLA‐A2‐restricted, immunogenic peptide derived from the folate‐binding protein (FBP), is overexpressed in multiple malignancies. We conducted a phase I/IIa trial of the E39 + GM‐CSF vaccine with booster inoculations of either E39 or E39′ (an attenuated version of E39) to prevent recurrences in disease‐free endometrial and ovarian cancer patients(pts). Here, we present the final 24‐month landmark analysis. Patients and methods: HLA‐A2 + patients receiving E39 + GM‐CSF were included in the vaccine group (VG), and HLA‐A2‐ pts (or HLA‐A2 + patients refusing vaccine) were followed as the control group (CG). VG group received 6 monthly inoculations as the primary vaccine series (PVS) and were randomized to receive either E39 or E39′ booster inoculations. Demographic, safety, immunologic, and disease‐free survival (DFS) data were collected and evaluated. Results: Fifty‐one patients were enrolled; 29 in the VG and 22 in the CG. Fourteen patients received <1000 μg and 15 received 1000 μg of E39. There were no clinicopathologic differences between VG and CG or between dose groups. E39 was well tolerated. At the 24 months landmark, DFS was 55.5% (VG) vs 40.0% (CG), P = 0.339. Patients receiving 1000 μg and boosted patients also showed improved DFS (P < 0.03). DFS was improved in the 1000 μg group after treatment of primary disease (90.0% vs CG:42.9%, P = 0.007), but not in recurrent patients. In low‐FBP expressing patients, DFS was 100.0% (1000 μg), 50.0% (<1000 μg), and 25.0% (CG), P = 0.029. Conclusions: This phase I/IIa trial reveals that E39 + GM‐CSF is safe and may be effective in preventing recurrence in high‐risk ovarian and endometrial cancer when optimally dosed (1000 μg) to FBP low patients being treated for primary disease. [ABSTRACT FROM AUTHOR]

In this randomized phase Ib trial, we tested combining the E39 peptide vaccine with a vaccine created from E39’, an attenuated version of E39. Patients with breast or ovarian cancer, who were disease-free after standard of care therapy, were enrolled and randomized to one of three arms. Arm EE received six E39 inoculations; arm EE’ received three E39 inoculations followed by three E39’; and arm E’E received three E39’ inoculations, followed by three E39. Within each arm, the first five patients received 500 μg of peptide and the remainder received 1000 μg. Patients were followed for toxicity, and immune responses were measured. This initial analysis after completion of the primary vaccination series has confirmed the safety of both vaccines. Immune analyses suggest incorporating the attenuated version of the peptide improves immune responses and that sequencing of E39 followed by E39’ might produce the optimal immune response. Trial Registration: NCT02019524 [ABSTRACT FROM AUTHOR]

Introduction Tumor vaccines use various strategies to generate immune responses, commonly targeting generic tumor-associated antigens. The tumor lysate, particle-loaded, dendritic cell (TLPLDC) vaccine is produced from DC loaded with autologous tumor antigens, creating a patient-specific vaccine. Here, we describe initial phase I/IIa trial results. Methods This trial includes patients with any stage solid tumors, ECOG ≤1, and >4 months life-expectancy. A personalized vaccine is created using 1 mg of tumor and 120 ml blood (to isolate DC). Primary vaccination series (PVS) is four monthly inoculations. Patients are followed per standard of care (SOC). Endpoints include safety and tumor response (RECIST v1.1). Results 44 patients were enrolled and vaccinated consisting of 31 late stage patients with residual/measurable disease, and 13 disease-free patients after SOC therapies. While 4 patients progressed before completing the PVS, 12/31 (39%) demonstrated clinical benefit (2 complete responses, 4 partial responses, 6 stable disease). In the adjuvant setting, 46% of late stage patients remain disease free at a median of 22.5 months. Conclusions The TLPLDC vaccine is scalable, generates a personalized DC vaccine, and requires little autologous tumor tissue and few DC. The vaccine is safe, with primarily grade 0–2 toxicities, and nearly 40% clinical benefit rate in varied tumors, warranting further study. Trial Registration: ISRCTN81339386, Registered 2/17/2016. [ABSTRACT FROM AUTHOR]