A simplified algorithm for inference by lower conditional probabilities

Abstract Thanks to the notion of locally strong coherence, the satisfiability of proper logical conditions on subfamilies of the initial domain helps to simplify inferential processes based on lower conditional assessments. Actually, these conditions avoid also round errors that, on the other hand, appear solving numerical systems. In this paper we introduce new conditions to be applied to sets of particular pairs of events. With respect to more general conditions already proposed, they avoid an exhaustive search, so that a sensible time-complexity reduction is possible. The usefulness of these rules in inferential processes is shown by a diagnostic medical problem with thyroid pathology

Self-Aligning Finger Exoskeleton for the Mobilization of the Metacarpophalangeal Joint

In the context of hand and finger rehabilitation, kinematic compatibility is key for the acceptability and clinical exploitation of robotic devices. Different kinematic chain solutions have been proposed in the state of the art, with different trade-offs between characteristics of kinematic compatibility, adaptability to different anthropometries, and the ability to compute relevant clinical information. This study presents the design of a novel kinematic chain for the mobilization of the metacarpophalangeal (MCP) joint of the long fingers and a mathematical model for the real-time computation of the joint angle and transferred torque. The proposed mechanism can self-align with the human joint without hindering force transfer or inducing parasitic torque. The chain has been designed for integration into an exoskeletal device aimed at rehabilitating traumatic-hand patients. The exoskeleton actuation the unit has a series-elastic architecture for compliant human-robot interaction and has been assembled and preliminarily tested in experiments with eight human subjects. Performance has been investigated in terms of (i) the accuracy of the MCP joint angle estimation through comparison with a video-based motion tracking system, (ii) residual MCP torque when the exoskeleton is controlled to provide null output impedance and (iii) torque-tracking performance. Results showed a root-mean-square error (RMSE) below 5 degrees in the estimated MCP angle. The estimated residual MCP torque resulted below 7 mNm. Torque tracking performance shows an RMSE lower than 8 mNm in following sinusoidal reference profiles. The results encourage further investigations of the device in a clinical scenario

Impact of antimicrobial stewardship interventions on appropriateness of surgical antibiotic prophylaxis. How to improve

Background and Objectives: Surgical Site Infections (SSIs) are the most common healthcare-associated infections and represent a major clinical problem in terms of mortality, morbidity, length of stay and overall costs. The appropriateness of Surgical Antibiotic Prophylaxis (SAP) is a key component to reduce the SSIs while the inappropriateness is a major cause of some emerging infections and selection of antibiotic resistance, therefore increasing healthcare costs. For this reasons international and national guidelines have been developed to guide clinicians in the optimal use of SAP. The The overall compliance to these guidelines is poor, with a high heterogeneity and as a consequence there is no universally recognized intervention to improve the appropriateness of SAP. The antimicrobial stewardship program is a systematic approach to improve appropriateness of antimicrobial use, to optimize the treatment of infections and to minimize the adverse effects associated with antibiotic use, like antimicrobial resistance, toxicity and costs. We describe a successfully Antimicrobial Stewardship (AMS) intervention on SAP appropriateness. Material and Methods: The prospective study was conducted at “Santa Maria” tertiary hospital in Terni, Umbria, in 12 main surgical units and was organized in three subsequent phases . The hospital defined evidence-based guidelines for optimal use of SAP, approved a new workflow to optimize the process of ordering, dispensing, administering and documenting SAP and created a satellite pharmacy in the operative block . Phase 1: we analysed 2059 elective surgical cases from January to June 2018 for 3 SAP parameters of appropriateness: indication, choice, dose. Phase 2: in July 2018 an audit was performed to analyse the result ; we reviewed 1781 elective surgical procedures from July to December 2018 looking for the same 3 SAP parameters of appropriateness. Results: The comparative analysis between phase 1 and 2 has demonstrated that the correct indication has a significant improvement (p-value 0.00128), moving from 73.63% in phase 1 to 77.82% in phase 2. The choice of antibiotic has not shown any significant improvement (p-value 0.4863) . The correct dose significantly improved (p-value< 2.2 1016 ), rising from 71.75% in phase 1 to 86.19% in phase 2. The overall compliance had a significant improvement (p-value <5.6 1012) passing from 40.21% in tphase 1 to 51.15% in phase 2. Conclusions: Our prospective study demonstrated a model of succesfully antimicrobial stewardship intervention that improves appropriateness of SAP

Complete solutions to the problem of quantisation errors arising from digital measurements of a repeated square wave signal

This report documents the complete solutions to the problem of representing the posterior distribution for the pulse width modulation of a repeated square wave signal based on digital measurements of the duration .of the on and the off components of the waves

Axiomatic characterization of partial ordinal relations

In this paper we focus on the theoretical properties of non-numerical representation of the uncertainty. As usual, this representation is realized by an ``ordinal relation'' (or, equivalently, by a ``comparative scale'') among the ``entities'' (events, alternatives or acts) of a specific problem. After giving an overview of di erent known axioms characterizing some classes of ordinal relations (and their duals), we introduce some axioms to enclose the necessary and su cient conditions for the representability of ordinal relations (defined on arbitrary finite sets of events) by the most-known uncertainty measures

Standard and nonstandard representability of positive uncertainty orderings

Axioms are given for positive comparative probabilities and plausibilities defined either on Boolean algebras or on arbitrary sets of events. These axioms allow to characterize binary relations representable by either standard or nonstandard measures (i. e. taking values either on the real field or on a hyperreal field). We also study relations between conditional events induced by preferences on conditional acts

Incoherence correction strategies in statistical matching

Several economic applications require to consider different data sources and to integrate the information coming from them. This paper focuses on statistical matching, in particular we deal with incoherences. In fact, when logical constraints among the variables are present incoherencies on the probability evaluations can arise. The aim of this paper is to remove such incoherences by using different methods based on distances minimization or least commitment imprecise probabilities extensions. An illustrative example shows peculiarities of the different correction methods. Finally, limited to pseudo distance minimization, we performed a systematic comparison through a simulation study. (c) 2012 Elsevier Inc. All rights reserved

A note on the equivalence between certain equivalent and least expected penalization criteria

In this paper we face the problem of the uniqueness of the quadratic penalty func-tion. We show an elementary case where the equivalence between certain equivalent and least expected penalization criteria reached by means of a wider class than the quadratic one. The uniqueness is obtained only imposing a symmetry condition

Non additive ordinal relations representable by lower or upper probabilities

summary:We characterize (in terms of necessary and sufficient conditions) binary relations representable by a lower probability. Such relations can be non- additive (as the relations representable by a probability) and also not “partially monotone” (as the relations representable by a belief function). Moreover we characterize relations representable by upper probabilities and those representable by plausibility. In fact the conditions characterizing these relations are not immediately deducible by means of “dual” conditions given on the contrary events, like in the numerical case

Standard and nonstandard representability of positive uncertainty orderings

summary:Axioms are given for positive comparative probabilities and plausibilities defined either on Boolean algebras or on arbitrary sets of events. These axioms allow to characterize binary relations representable by either standard or nonstandard measures (i. e. taking values either on the real field or on a hyperreal field). We also study relations between conditional events induced by preferences on conditional acts