Mathematical model for osteosarcoma progression and treatments

Cancer is a complex disease where every tumor has its own characteristics, and thus different tumors may respond differently to the same treatments. Osteosarcoma, which is a rare type of cancer with poor prognosis, is especially characterized by its high heteogeneity. Therefore, it is important to study the progression of osteosarcoma tumors in different groups of patients with distinct characteristics. The immune system has been reported to play an important role in the development of various cancers with some immune cells having anti-tumor effects and others having pro-tumor effects. With recent advances in digital cytometry methods, which are techniques to estimate the fractions of various cell types from gene expression data of a bulk of cells, it became possible to obtain relative abundance of immune cells in tumors. In this project, we review common digital cytometry methods, compare their performances and report the best method. We apply this best performing digital cytometry method to estimate abundance of immune cells in osteosarcoma tumors, and perform clustering using the estimated immune fractions to find groups of tumors with distinct immune compositions. We then model the growth of osteosarcoma tumors in each group while taking into account the interactions between immune cells and cancer cells. Lastly, we investigate the effects of adding chemotherapy on the progression of osteosarcoma, find the optimal chemotherapy dosages for tumors in each cluster, and compare the behaviors of immune and cancer cells under several conditions such as different treatment regimens and various treatment start times

Comparing leadership internationally: challenges and reflections

This paper is a co-written paper by five MA Education students at the University of Northampton and James Underwood, Principal Lecturer at the University of Northampton and a PhD student at the University of Cambridge. We are all currently engaged in research that involves comparing aspects of education in the UK with another nation. The research that we are each personally undertaking addresses a range of topics. These all relate to an aspect of education leadership ranging from student leadership to school and university management. There is one common underlying research question which underpins all the studies which is: in what ways has comparison between nations been a valid approach to understanding education and leadership? This question is addressed successively via our individual stories in this paper. This paper is linked to a paper presented in May 2015 at the University of Cambridge entitled: “Breaking boundaries as writers, researchers and me-searchers, the challenges and rewards of completing an MA as a community of practice.” In which we discussed in depth our experience as a research community. This paper has therefore also been informed by a distinct perspective on the nature of Masters’ level study

On the Convergence to a Global Solution of Shuffling-Type Gradient Algorithms

Stochastic gradient descent (SGD) algorithm is the method of choice in many machine learning tasks thanks to its scalability and efficiency in dealing with large-scale problems. In this paper, we focus on the shuffling version of SGD which matches the mainstream practical heuristics. We show the convergence to a global solution of shuffling SGD for a class of non-convex functions under over-parameterized settings. Our analysis employs more relaxed non-convex assumptions than previous literature. Nevertheless, we maintain the desired computational complexity as shuffling SGD has achieved in the general convex setting.Comment: The 37th Conference on Neural Information Processing Systems (NeurIPS 2023

Co-doping red-emitting Sr2Si5N8:Eu2+ into yellow-emitting phosphor-packaging for enhancing the optical properties of the 8500 K remote-phosphor packaging wleds

In the last decades, WLEDs attract more and more consideration in both academic and industrial purposes because of its advantages such as fast response time, environment friendliness, small size, long lifetime, and high efficiency. In this research, by doping the red-emitting Sr2Si5N8:Eu2+ phosphor particles into yellow-emitting YAG:Ce phosphor-packaging, a new recommendation for enhancing the optical properties (color uniformity, color rendering index, and lumen output) of the 8500 K remote-phosphor packaging WLEDs is presented, investigated, and demonstrated. By using Mat Lab and Light Tools software based on Mie Theory, the obtained results show that the optical properties of the 8500 K remote-phosphor packaging WLEDs significantly depended on Sr2Si5N8:Eu2+ concentration. The results have provided a potential practical recommendation for manufacturing remote-phosphor W-LEDs.Web of Science1341034102

THE PRICE OF NON-COOPERATION IN RESERVATION-BASED BANDWIDTH SHARING PROTOCOLS

ABSTRACTIn reservation-based bandwidth sharing protocols, the base station relies on the stations’ requests to allocate time slots to them. Like most  other protocols, reservation-based protocols were designed with the assumption that all stationsrespect the rules of the protocols. However, as mobile devices are becoming more intelligent andprogrammable, they can selfishly optimize their operations to obtain a larger share of commonbandwidth. Here, we study reservation-based bandwidth sharing protocols considering the existence of selfish stations through game-theoretic perspectives. We show that this game admits a Nash  equilibrium. Then, we prove the inefficiency of the Nash equilibrium. Game-theoretical analysis shows that local optimization in the bandwidth sharing problem with conflicted interests does not lead to any global optimization.Keywords. Nash equilibrium, Repeated game, Reservation-based

DIMENSIONS OF TRUST IN THE ACCEPTANCE OF INTER-ORGANIZATIONAL INFORMATION SYSTEMS IN NETWORKS: TOWARDS A SOCIO-TECHNICAL PERSPECTIVE

In the context of collaborative networks, networked inter-organizational information systems (IOIS) play a major role by providing a shared virtual space for the informal exchange of semi-structured or unstructured knowledge. Since IT support is seen as crucial for the whole network endeavor, the perspective of system acceptance becomes important. However, discussing IS adoption at the interorganizational level brings trust into the story. Building upon socio-technical theory, this study seeks to understand the role of two dimensions of trust in the acceptance of networked IOIS. A theoretical model is developed and subsequently tested with a sample of 121 German network organizations. Network trust reveals to be important for the perceived usefulness of the system, as the main benefit comes from members’ participation. Trust in technology shows to be an even more relevant determinant for the attitude towards the system. We suggest that future adoption studies should pay more attention on the interplay of both the social- as well as the technical-relations

SYNTHESIZING AND INTEGRATING RESEARCH ON IT-BASED VALUE CO-CREATION: A META-ANALYSIS

Recently, competition has shifted from the firm to the network level. Following this path, a growing stream in IT value research has emerged, aiming to understand how multiple firms create value through joint IT resources and capabilities. Despite the efforts made thus far, there are inconsistencies regarding construct definitions and divergent empirical findings. In this paper, we synthesize and integrate the body of knowledge on IT-based value co-creation. Drawing on the relational view, we first synthesize the existing empirical findings. The results of a meta-analysis of 72 studies encompassing 33,732 observations underline the importance of four sources of IT value: IT-based inter-organizational assets, IT-based knowledge sharing, IT-based complementary capabilities, and IT-based governance. A further moderator meta-analysis integrates divergent empirical findings in the literature. We find that objective measures dampen the relationship between inter-organizational IT and business value, while process-level measures and IT capabilities strengthen it. Moreover, we find evidence for higher value impacts in developing countries and an influence of inter-organizational relationship types. This study contributes by clarifying the IT-business value relationship and offers insights into sources of inconsistencies in IT-based value co-creation studies. By doing so, this paper lays a foundation for future research and theory development

Synthesizing and Integrating Research on IT-Based Value Cocreation: A Meta-Analysis

IT value research has witnessed growing interest in the use of joint IT resources and capabilities following recent shifts in market competition from the firm to the network level. Despite research efforts in this domain, there remain substantial inconsistencies in the IT value cocreation literature regarding the effect of interorganizational IT on business value and the role of methodological and contextual factors. Drawing on the resource-based view and the relational view of the firm, we conducted a meta-analysis to synthesize and integrate the body of knowledge of IT-based value cocreation. Our analysis of 80 studies, encompassing 21,843 observations, highlights the value-generating effect of four interorganizational IT capabilities: IT-based relation-specific assets, IT-based knowledge sharing, IT-based complementary capabilities, and IT-based governance. Insights from our preliminary meta-analysis reveal that contradictory findings are driven by the conceptualization of IT variables as interorganizational IT resources. A further moderator meta-analysis explains divergent empirical findings in the literature. We find that the use of relational-level value and perceptual measures, use of single respondents, and the context of developing countries and supply chain and networked interdependencies result in larger estimates of business value. In contrast, the use of network-level, firm-level, and objective measures; use of matched-pair approaches; and the context of developed countries and pooled interdependencies result in smaller estimates. Overall, this paper provides clarity and structure to the current understanding of the research field by providing explanations for inconsistent findings as well as a foundation for future research and theory development

Regression of murine lung tumors by the let-7 microRNA.

MicroRNAs (miRNAs) have recently emerged as an important new class of cellular regulators that control various cellular processes and are implicated in human diseases, including cancer. Here, we show that loss of let-7 function enhances lung tumor formation in vivo, strongly supporting the hypothesis that let-7 is a tumor suppressor. Moreover, we report that exogenous delivery of let-7 to established tumors in mouse models of non-small-cell lung cancer (NSCLC) significantly reduces the tumor burden. These results demonstrate the therapeutic potential of let-7 in NSCLC and point to miRNA replacement therapy as a promising approach in cancer treatment