The Effects of Differentiated Mathematics Rotations on Basic Facts

The purposes of this research were to examine the effects of differentiated mathematics rotations on student achievement, in the area of addition and subtraction fact fluency to ten, and how mathematics rotations influenced students’ feelings towards mathematics. The study was conducted over a six-week period in a first-grade classroom in a Midwestern state. Data collection methods included student feedback, addition assessments, subtraction assessments, and teacher observational checklist. The results of the study indicated an overall increase in both addition and subtraction fact fluency and students expressed more positive feelings towards mathematics. Both teacher researchers will continue to use mathematic rotations as the main framework in their classrooms to increase student achievement and continue to create more positive feelings towards mathematics. Further research topics include the effects of mathematics rotations on other mathematics standards and the effects of mathematics rotations throughout all grade levels

Wer weiß was? – Digitale Privatsphäre und App-Literacy aus Nutzerperspektive

Der zügellose Konsum mobiler Applikationen wird in der Literatur unter anderem mit theoretischen Konstrukten wie dem Privatsphäre-Paradox erklärt. Da diese theoretische Grundlage die Perspektive der Nutzer und deren spezifische Vorbildung vollkommen außer Acht lässt, adressiert der Artikel die App-Literacy der Nutzer um zu ergründen, ob sich Nutzer im Umgang mit Privatsphäre paradox verhalten. Anhand einer qualitativen empirischen Studie wird die spezifische Bildung der Nutzer bestimmt und anhand einer Inhaltsanalyse gezeigt, dass die Nutzer die durch mobile Applikationen drohenden Privatsphäre-Gefahren aufgrund ihrer zu niedrigen App-Literacy nicht einschätzen können und sich somit nicht paradox verhalten. Der Artikel zeigt, dass Nutzer Angebote mobiler digitaler Ökosysteme zwar ausgiebig in Anspruch nehmen, die daraus entstehenden Gefahren jedoch nicht kennen und somit auch nicht einschätzen und bewerten können

Differential interaction of glimepiride and glibenclamide with the β-cell sulfonylurea receptor I. Binding characteristics

Glimepiride is a novel sulfonylurea drug for treatment of non-insulin-dependent diabetes mellitus with higher blood sugar lowering efficacy in diabetic patients than glibenclamide raising the question whether this characteristics is in line with different binding of glimepiride and glibenclamide to the β-cell sulfonylurea receptor. Scatchard plot analysis of [3H]sulfonylurea binding to membranes isolated from rat β-cell tumors and (RINm5F) insulinoma cells and to RINm5F cells demonstrated that glimepiride has a 2.5–3-fold lower affinity than glibenclamide. This corresponded well to the 8–9-fold higher koff and 2.5–3-fold higher kon rates of glimepiride compared to glibenclamide as revealed by the dissociation and association kinetics of [3H]sulfonylurea binding and the Kd values calculated thereof. In agreement, the concentrations required for half-maximal displacement of [3H]sulfonylurea bound to β-cell membranes were significantly higher for glimepiride compared to glibenclamide. However, the binding affinity of glimepiride measured by both equilibrium binding and kinetic binding studies upon solubilization of β-cell tumor membranes and RINm5F cell membranes increased up to the value for glibenclamide. This was primarily based on a drastic decrease of the dissociation rate constant of glimepiride whereas the kinetics of glibenclamide binding remained largely unaffected upon solubilization. These data suggest that the Kd value alone is not sufficient for characterization of a sulfonylurea drug, since the kinetic binding parameters may also determine its acute blood sugar lowering efficacy

Tetrahydrouridine Inhibits Cell Proliferation through Cell Cycle Regulation Regardless of Cytidine Deaminase Expression Levels

Tetrahydrouridine (THU) is a well characterized and potent inhibitor of cytidine deaminase (CDA). Highly expressed CDA catalyzes and inactivates cytidine analogues, ultimately contributing to increased gemcitabine resistance. Therefore, a combination therapy of THU and gemcitabine is considered to be a potential and promising treatment for tumors with highly expressed CDA. In this study, we found that THU has an alternative mechanism for inhibiting cell growth which is independent of CDA expression. Three different carcinoma cell lines (MIAPaCa-2, H441, and H1299) exhibited decreased cell proliferation after sole administration of THU, while being unaffected by knocking down CDA. To investigate the mechanism of THU-induced cell growth inhibition, cell cycle analysis using flow cytometry was performed. This analysis revealed that THU caused an increased rate of G1-phase occurrence while S-phase occurrence was diminished. Similarly, Ki-67 staining further supported that THU reduces cell proliferation. We also found that THU regulates cell cycle progression at the G1/S checkpoint by suppressing E2F1. As a result, a combination regimen of THU and gemcitabine might be a more effective therapy than previously believed for pancreatic carcinoma since THU works as a CDA inhibitor, as well as an inhibitor of cell growth in some types of pancreatic carcinoma cells

Growth and Production of Shiitake Mushrooms on Lignocellulosic Waste Materials

Shiitake mushrooms have not previously been cultivated on a large scale in South Dakota. This research project was, therefore, conducted to generate baseline information about the growth and mushroom production potential of L. edodes on agricultural and forestry residues available in the state. It was anticipated that this information could then be used as a basis upon which further research projects could be designed, with the ultimate goal of establishing a shiitake mushroom production industry in South Dakota. In order to accomplish this goal of defining the baseline metabolic requirements and characteristics of L. edodes, the project addressed five main questions: 1. What are the general morphological characteristics and growth rates of different strains of L. edodes on various agar media? 2. What media and environmental conditions are best suited for maintaining shiitake culture collections at this facility? 3. What liquid media provides the best submerged culture growth of L. edodes? 4. Can shiitake mushrooms be produced on substrate materials found in South Dakota? 5. Can shiitake production be used as an aid in biodegradation of waste materials? Answers to these questions were based on, and developed from, the data gathered in the three phases of this experiment