Northern Illinois University

About: Northern Illinois University is a education organization based out in DeKalb, Illinois, United States. It is known for research contribution in the topics: Large Hadron Collider & Population. The organization has 8818 authors who have published 20008 publications receiving 632341 citations. The organization is also known as: NIU.

ATLAS b-jet identification performance and efficiency measurement with tt¯ events in pp collisions at √s = 13 TeV

Abstract: The algorithms used by the ATLAS Collaboration during Run 2 of the Large Hadron Collider to identify jets containing b-hadrons are presented. The performance of the algorithms is evaluated in the s ...

Structural and magnetic phase diagrams of La 1-x Sr x MnO 3 and Pr 1-y Sr y MnO 3

Abstract: The nuclear and magnetic structures and properties of ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{MnO}}_{3}$ with $0.45l~xl~1$ and ${\mathrm{Pr}}_{1\ensuremath{-}y}{\mathrm{Sr}}_{y}{\mathrm{MnO}}_{3}$ $(0.58l~yl~1)$ were investigated using neutron powder diffraction, resistivity and magnetic measurements. In this paper, we present the full magnetic and structural phase diagram for ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{MnO}}_{3}$ and a partial phase diagram for ${\mathrm{Pr}}_{1\ensuremath{-}y}{\mathrm{Sr}}_{y}{\mathrm{MnO}}_{3}.$ At low temperatures, we observe a series of structural phase transitions evolving as a function of increasing x as follows: orthorhombic $\mathrm{Pbn}\stackrel{\ensuremath{\rightarrow}}{m}\mathrm{rhombohedral}$ $R3\ifmmode\bar\else\textasciimacron\fi{}\stackrel{\ensuremath{\rightarrow}}{c}\mathrm{orthorhombic}$ $\mathrm{Fmm}\stackrel{\ensuremath{\rightarrow}}{m}\mathrm{tetragonal}$ $I4/mc\stackrel{\ensuremath{\rightarrow}}{m}\mathrm{cubic}$ $\mathrm{Pm}3\ifmmode\bar\else\textasciimacron\fi{}m.$ At higher temperatures, the orthorhombic Fmmm structural region disappears. We also identify four magnetic states (FM, A, C, and G type) evolving as a function of increasing x. The magnetic and nuclear structural transitions coincide for samples with $0.8l~xl~0.95.$ In the $0.5l~xl~0.9$ region, resistivity and magnetic measurements show a substantial hysteresis near ${T}_{N}.$ This hysteresis of a few K is indicative of a first order antiferromagnetic transition in good agreement with the neutron diffraction results. Our data also suggest the existence of a strong competition between the ferromagnetic and A-type states for $x\ensuremath{\sim}0.5,$ and between the C- and G-type states for $x\ensuremath{\sim}0.95.$ A similar behavior is observed for ${\mathrm{Pr}}_{1\ensuremath{-}y}{\mathrm{Sr}}_{y}{\mathrm{MnO}}_{3}.$

Feedback repression of polyamine transport is mediated by antizyme in mammalian tissue-culture cells.

Abstract: Antizyme, a spermidine-induced protein that binds and stimulates ornithine decarboxylase degradation, is now shown also to mediate the rapid feedback inhibition of polyamine uptake into mammalian cells. Using a cell line (HZ7) transfected with truncated antizyme cDNA, and mutant ornithine decarboxylase cell lines, we demonstrate that this newly discovered action of antizyme is distinct from its role in modulating polyamine biosynthesis.

Is Pedagogical Content Knowledge (PCK) Necessary for Reformed Science Teaching?: Evidence from an Empirical Study

Abstract: This study tested a hypothesis that focused on whether or not teachers’ pedagogical content knowledge (PCK) is a necessary body of knowledge for reformed science teaching. This study utilized a quantitative research method to investigate the correlation between a teacher’s PCK level as measured by the PCK rubric (Park et al. 2008) and the degree to which his/her classroom is reform-oriented as measured by RTOP (Sawada et al. 2002). Data included 33 instructional sessions of photosynthesis and heredity videotaped with 7 high school biology teachers. Each session was given a score on both the PCK rubric and RTOP by two independent raters. Results indicate that PCK score is significantly related to RTOP score in terms of both total score (r = .831, p < .01) and sub-component scores (ranging from r = .616 to .805, p < .01). Implications for science teacher education and future research are discussed.

Trust Matters: Examining the Role of Source Evaluation in Students' Construction of Meaning Within and Across Multiple Texts

Abstract: Students obtain information from a variety of sources that vary with respect to their trustworthiness. And, while the trustworthiness of a source ought to influence the weight and position that the information in a document plays in students' overall comprehension of a topic, there is little empirical evidence of this relationship. In this study, the authors examine whether source evaluation is related to single or cross-document comprehension. Participants read seven texts on global warming that varied on important source characteristics. The authors found that both trustworthiness ratings of the most reliable documents and the use of document type as rating criteria independently predicted comprehension. The authors also found both similarities and differences between source evaluation regarding a science topic compared to history topics. Several possible mechanisms for the observed relationship between source evaluation and comprehension when students use multiple texts are discussed. يحصل الطلبة على معلومات من مصادر متنوعة تختلف من حيث مصداقيتها. ومع أن مصداقية المصدر ينبغي أن تؤثر في وزن المعلومة وموقفها في النص بالنسبة لاستيعاب الطلبة الموضوع فإنه ليس هناك براهين تجريبية لتثبت هذه العلاقة. وفي هذه الدراسة نتقصى إذا كان تقييم المصدر يتعلق باستيعاب وثيقة منفردة ووثائق متشابكة. لقد قرأ المشاركون سبعة نصوص عن الاحتباس الحراري وكل نص يختلف عن الآخر من حيث خصائص المصدر المهمة. لقد وجدنا أن كلا تصانيف مصداقية الوثائق الأكثر ثقة واستعمال نوع الوثيقة كمقياس تصنيفي قد تنبآ الاستيعاب على حدة. ووجدنا أيضا تشابهات واختلافات بين تقييم المصدر بشأن مقارنة موضوع علمي بمواضيع تاريخية. لقد تم النقاش عن عدة آليات محتملة للعلاقة الملحوظة بين تقييم المصدر والاستيعاب حين يستخدم الطلبة نصوصا متنوعة. 学生从各种来源得到可信度高低不同的资料。虽然资料来源的可信度会影响学生对所得资料的重要性和观点与角度的衡量，从而影响他们对某一课题资料的整体理解；可是这种关系的经验研究证据却很少。在本研究中，我们考查资料来源评估是否与单一文件和跨文件的阅读理解相关。参加者阅读七篇有关全球变暖的资料文件，而其重要来源特征却有所不同。研究结果显示，最可靠文件的可信度评级和以文件种类作为评级标准，均可以独立预测阅读理解能力。研究结果亦显示，学生在阅读科学和历史课题时，对资料来源可信度的评估有相同地方，也有差异的地方。本文讨论几种可能的机制，以解释学生阅读多种文本时，对资料来源的评估与阅读理解能力之间的关系。 Les etudiants trouvent l'information dans toutes sortes de sources dont le degre de fiabilite est variable. Et, alors que la fiabilite du document influe sans doute sur le poids et la position que l'information qu'il contient joue dans la comprehension generale du theme etudie, on dispose de peu de donnees empiriques a ce propos. Nous examinons dans cette etude si l'evaluation de la source est liee a la comprehension d'un seul document isole ou de plusieurs documents. Les participants ont lu sept textes sur le rechauffement global qui variaient selon d'importantes caracteristiques de la source. Nous avons trouve que les evaluations de la fiabilite des documents les plus fiables, tout comme l'utilisation d'un type de document comme critere d'evaluation, permettent de predire la comprehension de facon independante. Nous avons aussi trouve a la fois des similitudes et des differences entre l'evaluation de la source d'un theme de science et d'un theme d'histoire. La discussion porte sur les divers mecanismes possibles de la relation observee entre l'evaluation de la source et la comprehension quand les etudiants utilisent plusieurs textes. Ученики получают информацию из разнообразных, не всегда надежных источников. Понятно, что заслуживающий доверия источник должен играть более значительную роль при освоении темы, однако на деле так происходит не всегда. В этом исследовании проверялось, является ли оценка того или иного источника результатом сравнения нескольких документов или источник оценивается на основе лишь одного документа. Участники исследования прочитали семь текстов о глобальном потеплении, взятые из различных источников. Выяснилось, что на их восприятие независимо друг от друга влияли два параметра: степень доверия к источнику, сформированная на основе нескольких документов, и тип документа как таковой. Мы также определили сходства и различия между оценкой источников, связанных с историей и естественными науками. В статье обсуждаются возможные механизмы для оценивания надежности информации при работе с текстами из разных источников. Los estudiantes obtienen informacion de varias fuentes cuya fiabilidad varia. Y, aunque la fiabilidad de una fuente deberia influenciar el peso y el papel que la informacion de tal documento debe desempenar en la comprension general del asunto, hay poca evidencia empirica de tal asociacion. En este estudio, nos preguntamos si la evaluacion de fuentes tiene alguna asociacion con la comprension de documentos sencillos y documentos contrarios. Los participantes leyeron siete textos sobre el calentamiento global. Las fuentes de estos textos diferian en aspectos importantes. Se descubrio que tanto el indice de fiabilidad de los documentos mas fidedignos como el uso de la clase de documento como indice de criterio podian predecir por si solos la comprension. Tambien se encontraron diferencias y similitudes entre la evaluacion de las fuentes de material cientifico comparado a los de historia. Se discuten varios mecanismos posibles para la asociacion observada entre la evaluacion de las fuentes y la comprension cuando los estudiantes usan varios textos.