Noncommutative polynomial maps

Accepté pour publication dans "Journal of Algebra and its applications"; 16 pages.Polynomial maps attached to polynomials of an Ore extension are naturally defi ned. In this setting we show the importance of pseudo-linear transformations and give some applications. In particular, factorizations of polynomials in an Ore extension over a fi nite fi eld F_q[t;S ], where S is the Frobenius automorphism, are translated into factorizations in the usual polynomial ring F_q[x]

Effect of a self-care educational intervention to improve self-care adherence among patients with chronic heart failure: a clustered randomized controlled trial in Northwest Ethiopia

Background: As the burden of cardiovascular disease increases in sub-Saharan Africa, there is a growing need for low-cost interventions to mitigate its impact. Providing self-care health education to patients with chronic heart failure (CHF) is recommended as an intervention to prevent complications, improve quality of life, and reduce financial burdens on fragile health systems. However, little is known about health education’s effectiveness at improving CHF self-management adherence in sub-Saharan Africa. Therefore the present study aimed to assess the effectiveness of an educational intervention to improve self-care adherence among patients with CHF at Debre Markos and Felege Hiwot Referral Hospitals in Northwest Ethiopia. Methods: To address this gap, we adapted a health education intervention based on social cognitive theory comprising of intensive four-day training and, one-day follow-up sessions offered every four months. Patients also received illustrated educational leaflets. We then conducted a clustered randomized control trial of the intervention with 186 randomly-selected patients at Debre Markos and Felege Hiwot referral hospitals. We collected self-reported data on self-care behavior before each educational session. We analyzed these data using a generalized estimating equations model to identify health education's effect on a validated 8-item self-care adherence scale. Results: Self-care adherence scores were balanced at baseline. After the intervention, patients in the intervention group (n = 88) had higher adherence scores than those in the control group (n = 98). This difference was statistically significant (β = 4.15, p < 0.05) and increased with each round of education. Other factors significantly associated with adherence scores were being single (β = − 0.25, p < 0.05), taking aspirin (β = 0.76, p < 0.05), and having a history of hospitalization (β = 0.91, p < 0.05). Conclusions: We find that self-care education significantly improved self-care adherence scores among CHF patients. This suggests that policymakers should consider incorporating self-care education into CHF management

The effect of hourly nursing rounds on patient satisfaction at Debre Markos Referral Hospital, Northwest Ethiopia: A non-randomized controlled clinical trial

Background: Today, implementation of hourly bedside nursing rounds is an important component of evaluating the excellence of hospitals and it is one of the strategies to increase the quality of care. Nevertheless, there has been little emphasis on the implementation of hourly nursing rounds and limited evidence is available on its effect on patient satisfaction with nursing care in Ethiopia. Hence, the objective of this study was to determine the effect of hourly nursing rounds on patient satisfaction with nursing care. Methods: A quasi-experimental nonequivalent groups study design was used to determine the effect of hourly nursing rounds on patient satisfaction with nursing care at Debre Markos Referral Hospital. A convenience sample of 104 hospitalized patients participated in this study (52 in control and 52 intervention group). The control group received the usual care in the selected units compared with the intervention group who received care with hourly nursing rounds. Patient satisfaction with nursing care scores was taken on the second and fifth days of hospitalization in both groups. Independent t-test was used to compare the statistical difference between the mean satisfaction scores of the two groups. A P-value of less than 0.05 was considered significant. Results: The result of the t-test demonstrated that patients in the intervention group had a higher satisfaction score than patients in the control group on the second day of hospitalization although it was not statistically significant (P = 0.215). However, there was a significant difference in the mean satisfaction scores on the fifth day of hospitalization (from 71.02 ± 14.37 in the control group to 79.69 ± 12.21 in the intervention group, P = 0.001). Conclusion: This study revealed that patients in the intervention group have higher satisfaction scores than the control group, providing evidence that hourly nursing rounds improve patient satisfaction with nursing care and quality of care. Therefore, policymakers (FMoH) need to consider the implementation of consistent hourly nursing rounds in our hospitals to improve patient satisfaction and overall quality of care at large. Trial registration ID: PACTR201907735468929

Factorizations of Elements in Noncommutative Rings: A Survey

We survey results on factorizations of non zero-divisors into atoms (irreducible elements) in noncommutative rings. The point of view in this survey is motivated by the commutative theory of non-unique factorizations. Topics covered include unique factorization up to order and similarity, 2-firs, and modular LCM domains, as well as UFRs and UFDs in the sense of Chatters and Jordan and generalizations thereof. We recall arithmetical invariants for the study of non-unique factorizations, and give transfer results for arithmetical invariants in matrix rings, rings of triangular matrices, and classical maximal orders as well as classical hereditary orders in central simple algebras over global fields.Comment: 50 pages, comments welcom

Drag on a Flat Plate in Low-Reynolds-Number Gas Flows

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76324/1/AIAA-4120-186.pd

Game theory of mind

This paper introduces a model of ‘theory of mind’, namely, how we represent the intentions and goals of others to optimise our mutual interactions. We draw on ideas from optimum control and game theory to provide a ‘game theory of mind’. First, we consider the representations of goals in terms of value functions that are prescribed by utility or rewards. Critically, the joint value functions and ensuing behaviour are optimised recursively, under the assumption that I represent your value function, your representation of mine, your representation of my representation of yours, and so on ad infinitum. However, if we assume that the degree of recursion is bounded, then players need to estimate the opponent's degree of recursion (i.e., sophistication) to respond optimally. This induces a problem of inferring the opponent's sophistication, given behavioural exchanges. We show it is possible to deduce whether players make inferences about each other and quantify their sophistication on the basis of choices in sequential games. This rests on comparing generative models of choices with, and without, inference. Model comparison is demonstrated using simulated and real data from a ‘stag-hunt’. Finally, we note that exactly the same sophisticated behaviour can be achieved by optimising the utility function itself (through prosocial utility), producing unsophisticated but apparently altruistic agents. This may be relevant ethologically in hierarchal game theory and coevolution

Effect of hydrogen on ground state structures of small silicon clusters

We present results for ground state structures of small Si$_{n}$H (2 \leq \emph{n} \leq 10) clusters using the Car-Parrinello molecular dynamics. In particular, we focus on how the addition of a hydrogen atom affects the ground state geometry, total energy and the first excited electronic level gap of an Si$_{n}$ cluster. We discuss the nature of bonding of hydrogen in these clusters. We find that hydrogen bonds with two silicon atoms only in Si$_{2}$H, Si$_{3}$H and Si$_{5}$H clusters, while in other clusters (i.e. Si$_{4}$H, Si$_{6}$H, Si$_{7}$H, Si$_{8}$H, Si$_{9}$H and Si$_{10}$H) hydrogen is bonded to only one silicon atom. Also in the case of a compact and closed silicon cluster hydrogen bonds to the cluster from outside. We find that the first excited electronic level gap of Si$_{n}$ and Si$_{n}$H fluctuates as a function of size and this may provide a first principles basis for the short-range potential fluctuations in hydrogenated amorphous silicon. Our results show that the addition of a single hydrogen can cause large changes in the electronic structure of a silicon cluster, though the geometry is not much affected. Our calculation of the lowest energy fragmentation products of Si$_{n}$H clusters shows that hydrogen is easily removed from Si$_{n}$H clusters.Comment: one latex file named script.tex including table and figure caption. Six postscript figure files. figure_1a.ps and figure_1b.ps are files representing Fig. 1 in the main tex