A Case Study of Online Instructors and Their Quest for Greater Interactivity in Their Courses: Overcoming the Distance in Distance Education

The purpose of this study was to explore the attitudes and experiences of seven online instructors in Teacher Education (three from the United States, four from Israel) pertaining to the deliberate efforts they make to build interaction into their web-based classes to support learning. In the tradition of cooperative inquiry, the use of purposive sampling and a semi-structured interview protocol provided the best opportunity to describe, rather than explain, the perspectives of these instructors who are currently teaching online and developing within the medium. Participants expressed the need to establish quality interactions throughout their distance courses, yet acknowledged barriers they perceive in attaining desired levels of human relationship. They also discussed the importance of collaboration, caring, and context when creating and teaching courses in an online environment

Radiative cooling in collisionally and photo ionized plasmas

We discuss recent improvements in the calculation of the radiative cooling in both collisionally and photo ionized plasmas. We are extending the spectral simulation code Cloudy so that as much as possible of the underlying atomic data is taken from external databases, some created by others, some developed by the Cloudy team. This paper focuses on recent changes in the treatment of many stages of ionization of iron, and discusses its extensions to other elements. The H-like and He-like ions are treated in the iso-electronic approach described previously. Fe II is a special case treated with a large model atom. Here we focus on Fe III through Fe XXIV, ions which are important contributors to the radiative cooling of hot, 1e5 to 1e7 K, plasmas and for X-ray spectroscopy. We use the Chianti atomic database to greatly expand the number of transitions in the cooling function. Chianti only includes lines that have atomic data computed by sophisticated methods. This limits the line list to lower excitation, longer wavelength, transitions. We had previously included lines from the Opacity Project database, which tends to include higher energy, shorter wavelength, transitions. These were combined with various forms of the g-bar approximation, a highly approximate method of estimating collision rates. For several iron ions the two databases are almost entirely complementary. We adopt a hybrid approach in which we use Chianti where possible, supplemented by lines from the Opacity Project for shorter wavelength transitions. The total cooling including the lightest thirty elements differs significantly from some previous calculations

A Higher-Order Generalized Singular Value Decomposition for Comparison of Global mRNA Expression from Multiple Organisms

The number of high-dimensional datasets recording multiple aspects of a single phenomenon is increasing in many areas of science, accompanied by a need for mathematical frameworks that can compare multiple large-scale matrices with different row dimensions. The only such framework to date, the generalized singular value decomposition (GSVD), is limited to two matrices. We mathematically define a higher-order GSVD (HO GSVD) for N≥2 matrices , each with full column rank. Each matrix is exactly factored as Di = UiΣiVT, where V, identical in all factorizations, is obtained from the eigensystem SV = VΛ of the arithmetic mean S of all pairwise quotients of the matrices , i≠j. We prove that this decomposition extends to higher orders almost all of the mathematical properties of the GSVD. The matrix S is nondefective with V and Λ real. Its eigenvalues satisfy λk≥1. Equality holds if and only if the corresponding eigenvector vk is a right basis vector of equal significance in all matrices Di and Dj, that is σi,k/σj,k = 1 for all i and j, and the corresponding left basis vector ui,k is orthogonal to all other vectors in Ui for all i. The eigenvalues λk = 1, therefore, define the “common HO GSVD subspace.” We illustrate the HO GSVD with a comparison of genome-scale cell-cycle mRNA expression from S. pombe, S. cerevisiae and human. Unlike existing algorithms, a mapping among the genes of these disparate organisms is not required. We find that the approximately common HO GSVD subspace represents the cell-cycle mRNA expression oscillations, which are similar among the datasets. Simultaneous reconstruction in the common subspace, therefore, removes the experimental artifacts, which are dissimilar, from the datasets. In the simultaneous sequence-independent classification of the genes of the three organisms in this common subspace, genes of highly conserved sequences but significantly different cell-cycle peak times are correctly classified

Renin–Angiotensin–Aldosterone System inhibitors in patients with Covid-19

No abstract available

Urban turism perception and recommendation in Mexico City and Lima

Mexico City and Lima both have great cultural and historical value as they developed close to major pre-Columbian civilizations. When comparing their urban attractiveness factors, they present differences and similarities that need to be understood at a theoretical level. The study has practical implications as tourism officials and managers in each of these two cities can draw inspiration from the best practices of the other city. The method is quantitative, and the exploratory factorial analysis technique was used to reduce the variables in a group of factors. The results indicate that the different aspects of the cities? tourism attractiveness can be categorized into four factors: the nucleus, the tourist ecosystem, MICE & shows, and related services. A comparison of the two cities? Kruskal?Wallis test scores shows significant differences in terms of three variables: monuments and historic sites, museums and art galleries, and shops and commercial services

Cosmopolitanism in a Globalized World: An Interdisciplinary Perspective

In this chapter, we develop a conceptual framework for cosmopolitanism as an individual-level phenomenon situated at the intersection of the moral, political, and sociocultural perspectives. The framework explicates the interrelations between macrolevel dynamics and individual experiences in a globalized world. We conceptualize cosmopolitanism as an individual disposition manifested and enacted through identities, attitudes, and practices. We also highlight the diversity of individuals who can be considered cosmopolitans, including those who may not possess the classic cosmopolitan CV. Finally, the chapter explores the implications of cosmopolitanism for global organizations and global leadership

On the Connection Between Metal Absorbers and Quasar Nebulae

We establish a simple model for the distribution of cold gas around L* galaxies using a large set of observational constraints on the properties of strong MgII absorber systems. Our analysis suggests that the halos of L* galaxies are filled with cool gaseous clouds having sizes of order 1kpc and densities of ~10^{-2} cm^{-3}. We then investigate the physical effects of cloud irradiation by a quasar and study the resulting spectral signatures. We show that quasar activity gives rise to (i) extended narrow-line emission on ~100kpc scales and (ii) an anisotropy in the properties of the absorbing gas arising from the geometry of the quasar radiation field. Provided that quasars reside in halos several times more massive than those of L* galaxies, our model predictions appear to be in agreement with observations of narrow emission-line nebulae around quasars and the recent detections of ~100kpc cold gaseous envelopes around those objects, suggesting a common origin for these phenomena. We discuss the implications of our results for understanding absorption systems, probing quasar environments at high redshifts, and testing the quasar unification scheme.Comment: 15 pages, 13 figures (ApJ submitted

Radiative Cooling in Collisionally Ionized and Photoionized Plasmas

We discuss recent improvements in the calculation of the radiative cooling in both collisionally ionized and photoionized plasmas. We are extending the spectral simulation code CLOUDY so that as much as possible of the underlying atomic data are taken from external data bases, some created by others and some developed by the CLOUDY team. This paper focuses on recent changes in the treatment of many stages of ionization of iron, and discusses its extensions to other elements. The H- and He-like ions are treated in the isoelectronic approach described previously. Fe II is a special case treated with a large model atom. Here we focus on Fe III through Fe XXIV, ions which are important contributors to the radiative cooling of hot (T ∼ 105–107 K) plasmas and for X-ray spectroscopy. We use the Chianti atomic data base to greatly expand the number of transitions in the cooling function. Chianti only includes lines that have atomic data computed by sophisticated methods. This limits the line list to lower excitation, longer wavelength, transitions. We had previously included lines from the Opacity Project data base, which tends to include higher energy, shorter wavelength, transitions. These were combined with various forms of the ‘g-bar’ approximation, a highly approximate method of estimating collision rates. For several iron ions the two data bases are almost entirely complementary. We adopt a hybrid approach in which we use Chianti where possible, supplemented by lines from the Opacity Project for shorter wavelength transitions. The total cooling including the lightest 30 elements differs from some previous calculations by significant amounts