Development and Validation of the Computational Thinking Concepts and Skills Test

Calls for standardized and validated measures of computational thinking have been made repeatedly in recent years. Still, few such tests have been created and even fewer have undergone rig- orous psychometric evaluation and been made available to re- searchers. The purpose of this study is to report our work in de- veloping and validating a test of computational thinking concepts and skills and to compare different scoring methods for the test. This computational thinking exam is intended to be used in com- puting education research as a common measure of computational thinking so that the research community will be able to make more meaningful comparisons across samples and studies. The Computational Thinking Concepts and Skills Test (CTCAST) was administered to students in several courses, evaluated and revised, and then administered to another group of students. Part of the revision included changing half of the items to a multiple-select format. The test scores using the three scoring methods were com- pared to each other and to scores on a different test of core com- puter science knowledge. Results indicate the CTCAST and the test of core computer science knowledge measure similar, but not identical, aspects of students’ knowledge and skills, and that item- level statistics vary according to the scoring method that is used. Recommendations for using and scoring the test are presented

Development and Validation of the Computational Thinking Concepts and Skills Test

Calls for standardized and validated measures of computational thinking have been made repeatedly in recent years. Still, few such tests have been created and even fewer have undergone rig- orous psychometric evaluation and been made available to re- searchers. The purpose of this study is to report our work in de- veloping and validating a test of computational thinking concepts and skills and to compare different scoring methods for the test. This computational thinking exam is intended to be used in com- puting education research as a common measure of computational thinking so that the research community will be able to make more meaningful comparisons across samples and studies. The Computational Thinking Concepts and Skills Test (CTCAST) was administered to students in several courses, evaluated and revised, and then administered to another group of students. Part of the revision included changing half of the items to a multiple-select format. The test scores using the three scoring methods were com- pared to each other and to scores on a different test of core com- puter science knowledge. Results indicate the CTCAST and the test of core computer science knowledge measure similar, but not identical, aspects of students’ knowledge and skills, and that item- level statistics vary according to the scoring method that is used. Recommendations for using and scoring the test are presented

Development and Validation of the Computational Thinking Concepts and Skills Test

Calls for standardized and validated measures of computational thinking have been made repeatedly in recent years. Still, few such tests have been created and even fewer have undergone rig- orous psychometric evaluation and been made available to re- searchers. The purpose of this study is to report our work in de- veloping and validating a test of computational thinking concepts and skills and to compare different scoring methods for the test. This computational thinking exam is intended to be used in com- puting education research as a common measure of computational thinking so that the research community will be able to make more meaningful comparisons across samples and studies. The Computational Thinking Concepts and Skills Test (CTCAST) was administered to students in several courses, evaluated and revised, and then administered to another group of students. Part of the revision included changing half of the items to a multiple-select format. The test scores using the three scoring methods were com- pared to each other and to scores on a different test of core com- puter science knowledge. Results indicate the CTCAST and the test of core computer science knowledge measure similar, but not identical, aspects of students’ knowledge and skills, and that item- level statistics vary according to the scoring method that is used. Recommendations for using and scoring the test are presented

Spin-orbit coupling control of anisotropy, ground state and frustration in 5d2 Sr2MgOsO6

The influence of spin-orbit coupling (SOC) on the physical properties of the 5d2 system Sr2MgOsO6 is probed via a combination of magnetometry, specific heat measurements, elastic and inelastic neutron scattering, and density functional theory calculations. Although a significant degree of frustration is expected, we find that Sr2MgOsO6 orders in a type I antiferromagnetic structure at the remarkably high temperature of 108 K. The measurements presented allow for the first accurate quantification of the size of the magnetic moment in a 5d2 system of 0.60(2) μB –a significantly reduced moment from the expected value for such a system. Furthermore, significant anisotropy is identified via a spin excitation gap, and we confirm by first principles calculations that SOC not only provides the magnetocrystalline anisotropy, but also plays a crucial role in determining both the ground state magnetic order and the size of the local moment in this compound. Through comparison to Sr2ScOsO6, it is demonstrated that SOC-induced anisotropy has the ability to relieve frustration in 5d2 systems relative to their 5d3 counterparts, providing an explanation of the high TN found in Sr2MgOsO6

Spin-orbit coupling control of anisotropy, ground state and frustration in 5d2 Sr2MgOsO6

The influence of spin-orbit coupling (SOC) on the physical properties of the 5d2 system Sr2MgOsO6 is probed via a combination of magnetometry, specific heat measurements, elastic and inelastic neutron scattering, and density functional theory calculations. Although a significant degree of frustration is expected, we find that Sr2MgOsO6 orders in a type I antiferromagnetic structure at the remarkably high temperature of 108 K. The measurements presented allow for the first accurate quantification of the size of the magnetic moment in a 5d2 system of 0.60(2) muB - a significantly reduced moment from the expected value for such a system. Furthermore, significant anisotropy is identified via a spin excitation gap, and we confirm by first principles calculations that SOC not only provides the magnetocrystalline anisotropy, but also plays a crucial role in determining both the ground state magnetic order and the size of the local moment in this compound. Through comparison to Sr2ScOsO6, it is demonstrated that SOC-induced anisotropy has the ability to relieve frustration in 5d2 systems relative to their 5d3 counterparts, providing an explanation of the high TN found in Sr2MgOsO6.Comment: Submitted to Scientific Report

Hormone receptor status of a first primary breast cancer predicts contralateral breast cancer risk in the WECARE study population

Abstract Background Previous population-based studies have described first primary breast cancer tumor characteristics and their association with contralateral breast cancer (CBC) risk. However, information on influential covariates such as treatment, family history of breast cancer, and BRCA1/2 mutation carrier status was not available. In a large, population-based, case-control study, we evaluated whether tumor characteristics of the first primary breast cancer are associated with risk of developing second primary asynchronous CBC, overall and in subgroups of interest, including among BRCA1/2 mutation non-carriers, women who are not treated with tamoxifen, and women without a breast cancer family history. Methods The Women’s Environmental Cancer and Radiation Epidemiology Study is a population-based case-control study of 1521 CBC cases and 2212 individually-matched controls with unilateral breast cancer. Detailed information about breast cancer risk factors, treatment for and characteristics of first tumors, including estrogen receptor (ER) and progesterone receptor (PR) status, was obtained by telephone interview and medical record abstraction. Multivariable risk ratios (RRs) and 95% confidence intervals (CIs) were estimated in conditional logistic regression models, adjusting for demographics, treatment, and personal medical and family history. A subset of women was screened for BRCA1/2 mutations. Results Lobular histology of the first tumor was associated with a 30% increase in CBC risk (95% CI 1.0–1.6). Compared to women with ER+/PR+ first tumors, those with ER-/PR- tumors had increased risk of CBC (RR = 1.4, 95% CI 1.1–1.7). Notably, women with ER-/PR- first tumors were more likely to develop CBC with the ER-/PR- phenotype (RR = 5.4, 95% CI 3.0–9.5), and risk remained elevated in multiple subgroups: BRCA1/2 mutation non-carriers, women younger than 45 years of age, women without a breast cancer family history, and women who were not treated with tamoxifen. Conclusions Having a hormone receptor negative first primary breast cancer is associated with increased risk of CBC. Women with ER-/PR- primary tumors were more likely to develop ER-/PR- CBC, even after excluding BRCA1/2 mutation carriers. Hormone receptor status, which is routinely evaluated in breast tumors, may be used clinically to determine treatment protocols and identify patients who may benefit from increased surveillance for CBC

A phase I study evaluating the pharmacokinetics, safety and tolerability of an antibody-based tissue factor antagonist in subjects with acute lung injury or acute respiratory distress syndrome

<p>Abstract</p> <p>Background</p> <p>The tissue factor (TF)-dependent extrinsic pathway has been suggested to be a central mechanism by which the coagulation cascade is locally activated in the lungs of patients with acute lung injury and acute respiratory distress syndrome (ALI/ARDS) and thus represents an attractive target for therapeutic intervention. This study was designed to determine the pharmacokinetic and safety profiles of ALT-836, an anti-TF antibody, in patients with ALI/ARDS.</p> <p>Methods</p> <p>This was a prospective, randomized, placebo-controlled, dose-escalation Phase I clinical trial in adult patients who had suspected or proven infection, were receiving mechanical ventilation and had ALI/ARDS (PaO₂/FiO₂≤ 300 mm). Eighteen patients (6 per cohort) were randomized in a 5:1 ratio to receive ALT-836 or placebo, and were treated within 48 hours after meeting screening criteria. Cohorts of patients were administered a single intravenously dose of 0.06, 0.08 or 0.1 mg/kg ALT-836 or placebo. Blood samples were taken for pharmacokinetic and immunogenicity measurements. Safety was assessed by adverse events, vital signs, ECGs, laboratory, coagulation and pulmonary function parameters.</p> <p>Results</p> <p>Pharmacokinetic analysis showed a dose dependent exposure to ALT-836 across the infusion range of 0.06 to 0.1 mg/kg. No anti-ALT-836 antibody response was observed in the study population during the trial. No major bleeding episodes were reported in the ALT-836 treated patients. The most frequent adverse events were anemia, observed in both placebo and ALT-836 treated patients, and ALT-836 dose dependent, self-resolved hematuria, which suggested 0.08 mg/kg as an acceptable dose level of ALT-836 in this patient population.</p> <p>Conclusions</p> <p>Overall, this study showed that ALT-836 could be safely administered to patients with sepsis-induced ALI/ARDS.</p> <p>Trial registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT01438853">NCT01438853</a></p