Algorithmic Explanations: an Unplugged Instructional Approach to Integrate Science and Computational Thinking.

Computing has become essential in modern-day problem-solving, making computational literacy necessary for practicing scientists and engineers. However, K-12 science education has not reflected this computational shift. Integrating computational thinking (CT) into core science courses is an avenue that can build computational literacies in all students. Integrating CT and science involves using computational tools and methods (including programming) to understand scientific phenomena and solve science-based problems. Integrating CT and science is gaining traction, but widespread implementation is still quite limited. Several barriers have limited the integration and implementation of CT in K-12 science education. Most teachers lack experience with computer science, computing, programming, and CT and therefore are ill-prepared to integrate CT into science courses, leading to low self-efficacy and low confidence in integrating CT. This theoretical paper introduces a novel instructional approach for integrating disciplinary science education with CT using unplugged (computer-free) activities. We have grounded our approach in common computational thinking in STEM frameworks but translate this work into an accessible pedagogical strategy. We begin with an overview and critique of current approaches that integrate CT and science. Next, we introduce the Computational Thinking through Algorithmic Explanations (CT-AE) instructional approach. We then explain how CT-AE is informed by constructionist writing-to-learn science theory. Based on a pilot implementation with student learning outcomes, we discuss connections to existing literature and future directions.

Comparison of alfalfa plants overexpressing glutamine synthetase with those overexpressing sucrose phosphate synthase demonstrates a signaling mechanism integrating carbon and nitrogen metabolism between the leaves and nodules.

Alfalfa, like other legumes, establishes a symbiotic relationship with the soil bacteria, Sinorhizobium meliloti, which results in the formation of the root nodules. Nodules contain the bacteria enclosed in a membrane-bound vesicle, the symbiosome where it fixes atmospheric N2 and converts it into ammonia using the bacterial enzyme, nitrogenase. The ammonia released into the cytoplasm from the symbiosome is assimilated into glutamine (Gln) using carbon skeletons produced by the metabolism of sucrose (Suc), which is imported into the nodules from the leaves. The key enzyme involved in the synthesis of Suc in the leaves is sucrose phosphate synthase (SPS) and glutamine synthetase (GS) is the enzyme with a role in ammonia assimilation in the root nodules. Alfalfa plants, overexpressing SPS or GS, or both showed increased growth and an increase in nodule function. The endogenous genes for the key enzymes in C/N metabolism showed increased expression in the nodules of both sets of transformants. Furthermore, the endogenous SPS and GS genes were also induced in the leaves and nodules of the transformants, irrespective of the transgene, suggesting that the two classes of plants share a common signaling pathway regulating C/N metabolism in the nodules. This study reaffirms the utility of the nodulated legume plant to study C/N interaction and the cross talk between the source and sink for C and N.

Cardiorespiratory fitness in survivors of cervical, endometrial, and ovarian cancers: The Cooper Center Longitudinal Study.

BACKGROUND: Cardiorespiratory fitness (CRF), a strong predictor of mortality, is impaired among cancer patients. There is limited data, however, regarding CRF levels in women diagnosed with gynecologic cancers. METHODS: We compared CRF among ovarian, endometrial, and cervical cancer cases (n=89) to age-matched controls (n=89) in the Cooper Center Longitudinal Study (CCLS). CRF was evaluated by a maximal treadmill exercise tolerance test using a modified-Balke protocol. Conditional logistic regression was used to test for case-control differences in cardiorespiratory fitness, after controlling for age and body mass index, and adhering to the matched pairs design. RESULTS: The mean ages of cancer cases and controls were 50.9 years and 51.1 years, respectively (p=0.81). Peak METs (1 MET=3.5 mL kg(-1)min(-1)) were 9.2 ± 2.0 in cancer cases compared to 10.0 ± 2.2 in controls (p=0.03). When stratifying by type of cancer, peak METs were 8.9 ± 2.2, 8.4 ± 1.9, 9.5 ± 2.0 for patients with ovarian, endometrial, and cervical cancer, respectively. A gynecological cancer diagnosis was associated with greater odds of having 1-MET lower CRF compared to controls (OR 1.31, 95% CI: 1.05-1.64, p=0.018), after controlling for age and BMI. CONCLUSION: Gynecologic cancer survivors were more likely to have a 1-MET lower CRF than controls. Given a 1-MET change in CRF is associated with a significant, we advocate for more robust research regarding CRF in gynecologic cancer patients.

Impact of concurrent overexpression of cytosolic glutamine synthetase (GS1) and sucrose phosphate synthase (SPS) on growth and development in transgenic tobacco.

MAIN CONCLUSION: The outcome of simultaneously increasing SPS and GS activities in transgenic tobacco, suggests that sucrose is the major determinant of growth and development, and is not affected by changes in N assimilation. Carbon (C) and nitrogen (N) are the major components required for plant growth and the metabolic pathways for C and N assimilation are very closely interlinked. Maintaining an appropriate balance or ratio of sugar to nitrogen metabolites in the cell, is important for the regulation of plant growth and development. To understand how C and N metabolism interact, we manipulated the expression of key genes in C and N metabolism individually and concurrently and checked for the repercussions. Transgenic tobacco plants with a cytosolic soybean glutamine synthetase (GS1) gene and a sucrose phosphate synthase (SPS) gene from maize, both driven by the CaMV 35S promoter were produced. Co-transformants, with both the transgenes were produced by sexual crosses. While GS is the key enzyme in N assimilation, involved in the synthesis of glutamine, SPS plays a key role in C metabolism by catalyzing the synthesis of sucrose. Moreover, to check if nitrate has any role in this interaction, the plants were grown under both low and high nitrogen. The SPS enzyme activity in the SPS and SPS/GS1 co-transformants were the same under both nitrogen regimens. However, the GS activity was lower in the co-transformants compared to the GS1 transformants, specifically under low nitrogen conditions. The GS1/SPS transformants showed a phenotype similar to the SPS transformants, suggesting that sucrose is the major determinant of growth and development in tobacco, and its effect is only marginally affected by increased N assimilation. Sucrose may be functioning in a metabolic capacity or as a signaling molecule.

Cardiorespiratory fitness in breast cancer patients: a call for normative values.

BACKGROUND: There is emerging evidence that adjuvant treatments for breast cancer negatively impact cardiorespiratory fitness (CRF) or Vo2max, a key predictor of cardiovascular risk. Although a number of studies have measured CRF in breast cancer patients, there is currently limited data regarding expected CRF values in this patient population. Given that CRF is a poor prognostic sign and recently highlighted as a key measure to standardize by the American Heart Association, we sought to review the available literature on CRF among breast cancer patients. METHODS AND RESULTS: We identified 27 clinical trials and observational studies measuring Vo2max in the pre- and post-adjuvant treatment setting for breast cancer. We compared Vo2max before to Vo2max after adjuvant therapy and compared Vo2max in female breast cancer patients with Vo2max in healthy controls. CONCLUSIONS: We found that CRF was substantially lower in women with a history of breast cancer compared with healthy women and this was most pronounced among breast cancer patients in the post-adjuvant setting. We conclude that knowledge of normative CRF values is critical to tailor appropriately timed exercise interventions in breast cancer patients susceptible to low CRF and subsequent cardiovascular risk.