New York Institute of Technology

About: New York Institute of Technology is a education organization based out in Vancouver, British Columbia, Canada. It is known for research contribution in the topics: Population & Cloud computing. The organization has 1504 authors who have published 2435 publications receiving 64307 citations. The organization is also known as: NYIT & New York Institute of Technology, NYIT.

Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

Abstract: In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure flux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation, it is imperative to target by gene knockout or RNA interference more than one autophagy-related protein. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways implying that not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular assays, we hope to encourage technical innovation in the field.

Making knowledge the basis of a dynamic theory of the firm

Abstract: Knowledge is too problematic a concept to make the task of building a dynamic knowledge-based theory of the firm easy. We must also distinguish the theory from the resource-based and evolutionary views. The paper begins with a multitype epistemology which admits both the pre- and subconscious modes of human knowing and, reframing the concept of the cognizing individual, the collective knowledge of social groups. While both Nelson and Winter, and Nonaka and Takeuchi, successfully sketch theories of the dynamic interactions of these types of organizational knowledge, neither indicates how they are to be contained. Callon and Latour suggest knowledge itself is dynamic and contained within actor networks, so moving us from knowledge as a resource toward knowledge as a process. To simplify this approach, we revisit sociotechnical systems theory, adopt three heuristics from the social constructionist literature, and make a distinction between the systemic and component attributes of the actor network. The result is a very different mode of theorizing, less an objective statement about the nature of firms ‘out there’ than a tool to help managers discover their place in the firm as a dynamic knowledge-based activity system.

Recursively generated B-spline surfaces on arbitrary topological meshes

Abstract: This paper describes a method for recursively generating surfaces that approximate points lying-on a mesh of arbitrary topology. The method is presented as a generalization of a recursive bicubic B-spline patch subdivision algorithm. For rectangular control-point meshes, the method generates a standard B-spline surface. For non-rectangular meshes, it generates surfaces that are shown to reduce to a standard B-spline surface except at a small number of points, called extraordinary points. Therefore, everywhere except at these points the surface is continuous in tangent and curvature. At the extraordinary points, the pictures of the surface indicate that the surface is at least continuous in tangent, but no proof of continuity is given. A similar algorithm for biquadratic B-splines is also presented.

Knowledge and the firm: Overview

Abstract: The explosion of interest in knowledge and its management reflects the trend towards ‘knowledge work’ and the Information Age, and recognition of knowledge as the principal source of economic rent The papers in this Special Issue represent an attempt by strategy scholars (and some outside our traditional field) to come to terms with the implications of knowledge for the theory of the firm and its management They are the product of a convergence of several streams of research which have addressed management implications of knowledge, including the management of technology, the economics of innovation and information, resource-based theory, and organizational learning At the theoretical level, knowledge-centered approaches of Penrose, Arrow, Hayek and others have been enriched by contributions from evolutionary economists (notably Nelson and Winter) and epistemologists (notably M Polanyi) At the empirical level, research into innovation and its diffusion originated by Mansfield, Griliches and others has been extended through studies which investigate tacit as well as explicit knowledge, and explore knowledge transfer within as well as across firms

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)

Abstract: In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.