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Background: Peripheral Nerve Stimulation (PNS) is an established therapy for chronic neuropathic pain of peripheral origin, typically following nerve injury. However, there is a paucity of Randomized Controlled Trials (RCTs) demonstrating the therapeutic benefits of PNS. The goals of the current study (COMFORT Study) are to document the safety and efficacy of the Nalu Neurostimulation in a PNS RCT, compared to conventional medical management (CMM). Methods/Design: This is a prospective, multicenter, RCT evaluating the treatment of neuropathic pain with PNS therapy. One of the following four regions will be targeted for treatment: low back, shoulder, knee or foot/ankle. Consented subjects will undergo a baseline evaluation, after which they are randomized 2:1 (PNS+CMM arm to CMM arm). Subjects randomized to PNS+CMM arm will undergo a trial implant period using best clinical practices. Subjects who pass the trial phase, by showing a ≥ 50% reduction in pain relative to baseline, will receive the permanent implant. All subjects receiving a permanent implant will be followed for a total of 36 months. At the 3-month primary end point, subjects in CMM arm will be given the option to crossover into PNS+CMM arm, beginning with a trial implant. The study duration is expected to be 5.5 years from first enrollment to last follow-up of last subject and subsequent study closure. Adverse events will be captured throughout the study. Discussion: The COMFORT study, described here, has the potential to demonstrate the efficacy and safety of the Nalu Neurostimulation System in the treatment of peripheral neuropathy. Results of this study will be the first Level-I evidence, out to 36 months, validating the use of this PNS system in the treatment of chronic pain. This study is designed to enroll the largest cohort, to date, of subjects comparing PNS+CMM vs CMM alone. Plain Language Summary: Peripheral nerve stimulation (PNS) has been used for decades to treat neuropathic pain of peripheral origin. This therapy typically involves the placement small (~1 mm diameter) cylindrical electrodes (leads) near the nerve(s) in question, which is then followed by the delivery mild electrical pulses to the target, thereby blocking the pain signal from reaching the central nervous system. Despite the clinical success of this approach, there are few randomized controlled trials (RCTs) demonstrating PNS efficacy in the treatment of peripheral neuralgia/neuropathy. This may be, in large part, due to a paucity of PNS devices that are small enough to deliver this therapy at multiple locations in the extremities and the torso. For example, most implantable pulse generators (IPGs) range in size from 14 to 40 cm3 in volume. The purpose of this RCT is to demonstrate the safety and efficacy of an externally powered micro-IPG (< 1.5 cm3 in volume), in the delivery of PNS to treat peripheral neuropathic pain. Active Arm subjects will receive therapy with the micro-IPG and continue to use conventional medical management (CMM); Control Arm subjects will be treated with CMM only. The primary endpoint is the responder rate at 3-months, in both arms, defined as the percentage of subjects with ≥ 50% pain reduction from baseline following implantation of the micro-IPG. Control Arm subjects will be given the option to crossover to the Active Arm at 3-months. Study subjects in both arms are followed out to 36 months. [ABSTRACT FROM AUTHOR]

Introduction We evaluated risk factors for biochemical recurrence (BCR) after robot-assisted radical prostatectomy (RARP) based on our department database. Material and methods Patients who underwent RARP between 2018 and 2020 were identified and included in our retrospective study. Patients who received neoadjuvant treatment, patients with positive lymph nodes, salvage prostatectomies, and patients with missing data were excluded. BCR was defined as PSA ≥0.2 ng/ml. Parameters that were investigated were the International Society of Urological Pathologists (ISUP) score, stage, and positive surgical margins (PSM) as they were reported in the pathology report. A subgroup analysis based on the tumour stage was performed. Results A total of 414 patients were included in the analysis. Seventy-seven of them experienced BCR. Based on multivariable analysis, ISUP grade was a strong predictor for BCR with odds ratio (OR): 2.86 (CI: 1.49–5.65; p = 0.002), OR: 5.90 (CI: 1.81–18.6; p = 0.003), OR: 4.63 (CI: 1.79–11.9; p = 0.001) for ISUP grade 3, 4, 5, respectively. Regarding tumour stage, pT2 and pT3a did not show any significant difference in predicting BCR (p = 0.11), whereas pT3b stage was a predictor for BCR with OR: 6.2 (CI: 2.25–17.7; p < 0.001). In the subgroup analysis for 206 patients with pT2 disease, ISUP group and PSM were predictors for BCR. On the other hand, when patients with pT3 disease were inspected, the only parameter that was predictive of BCR was pT3b disease (OR: 4.68, CI: 1.71–13.6; p = 0.003). ISUP grade, the extent of T3 disease, and the extent and ISUP grade of surgical margins were not predictors of BCR. Conclusions The most important risk factors for BCR after RARP are ISUP grade and tumour stage. In pT2 disease, PSM is a significant predictor of BCR, along with high ISUP grade. The substage pT3b can be considered a predictor of BCR in pT3 cases. [ABSTRACT FROM AUTHOR]

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Remote attestation is a technology for establishing trust in a remote computing system. Copland is a domain-specific language for specifying attestation protocols that operate in diverse, layered measurement topologies. In this work, we formally define and verify the Copland Virtual Machine for executing Copland protocols alongside a dual generalized appraisal procedure. Together these components provide a principled pipeline to execute and bundle arbitrary Copland-based attestations, then unbundle and evaluate the resulting evidence for measurement content and cryptographic integrity. All artifacts are implemented as monadic, functional programs in the Coq proof assistant and verified with respect to the Copland reference semantics. Finally, we leverage formal properties of component implementations and their surrounding security architecture to aid in the design and analysis of attestation scenarios in the context of an active adversary attempting to subvert attestation. These components lay the foundation for a verified end-to-end attestation stack. [ABSTRACT FROM AUTHOR]

Our team has developed a model-based systems engineering environment that integrates formal methods at all levels of system design. Our methodology and tools enable systems engineers to address cybersecurity concerns early in the development of complex high-assurance systems. [ABSTRACT FROM AUTHOR]

Remote attestation consists of generating evidence of a system's integrity via measurements and reporting the evidence to a remote party for appraisal in a form that can be trusted. The parties that exchange information must agree on formats and protocols. We assert there is a large variety of patterns of interactions among appraisers and attesters of interest. Therefore, it is important to standardize on flexible mechanisms for remote attestation. We make our case by describing scenarios that require the exchange of evidence among multiple parties using a variety of message passing patterns. We show cases in which changes in the order of evidence collection result in important differences to what can be inferred by an appraiser. We argue that adding the ability to negotiate the appropriate kind of attestation allows for remote attestations that better adapt to a dynamically changing environment. Finally, we suggest a language-based solution to taming the complexity of specifying and negotiating attestation procedures. [ABSTRACT FROM AUTHOR]

This work examines the use of model checking techniques to verify system-level security properties of a collection of interacting virtualmachines. Specifically, we examine how local access control policies implemented in individual virtual machines and a hypervisor can be shown to satisfy global access control constraints. The SAL model checker is used to model and verify a collection of stateful domains with protected resources and local MAC policies attempting to access needed resources from other domains. The model is described along with verification conditions. The need to control state-space explosion is motivated and techniques for writing theorems and limiting domains explored. Finally, analysis results are examined along with analysis complexity. [ABSTRACT FROM AUTHOR]

A continuing challenge for software designers is to develop efficient and cost-effective software implementations. Many see software reuse as a potential solution; however, the cost of reuse tends to outweigh the potential benefits. The costs of software reuse include establishing and maintaining a library of reusable components, searching for applicable components to be reused in a design, as well as adapting components toward a proper implementation. In this paper, we introduce SPARTACAS, a framework for automating specification-based component retrieval and adaptation that has been successfully applied to synthesis of software for embedded and digital signal processing systems. Using specifications to abstractly represent implementations allows automated theorem-provers to formally verify logical reusability relationships between specifications. These logical relationships are used to evaluate the feasibility of reusing the implementations of components to implement a problem. Retrieving a component that is a complete match to a problem is rare. It is more common to retrieve a component that partially satisfies the requirements of a problem. Such components have to be adapted. Rather than adapting components at the code level, SPARTACAS adapts the behavior of partial matches by imposing interactions with other components at the architecture level. A subproblem is synthesized that specifies the missing functionality required to complete the problem; the subproblem is used to query the library for components to adapt the partial match. The framework was implemented and evaluated empirically, the results suggest that automated adaptation using architectures successfully promotes software reuse, and hierarchically organizes a solution to a design problem. [ABSTRACT FROM AUTHOR]

This paper describes a formal framework developed using the Prototype Verification System (PVS) to model and verify distributed simulation kernels based on the Time Warp paradigm. The intent is to provide a common formal base from which domain specific simulators can be modeled, verified, and developed. PVS constructs are developed to represent basic Time Warp constructs. Correctness conditions for Time Warp simulation are identified describing causal ordering of event processing and correct rollback processing. The PVS theorem prover and type-check condition system are then used to verify all correctness conditions. In addition, the paper discusses the framework's reusability and extensibility properties in support of specification and verification of Time Warp extensions and optimizations. [ABSTRACT FROM AUTHOR]

Introduces a heterogeneous systems-level modeling language supporting predictive design analysis. Design methodology of the model-based approach; Definition of system properties; Projection of design information from one domain to another. INSETS: Rosetta in Action.;Related Work..

In this paper we present a mechanism for making specification-based component retrieval more efficient by limiting the amount of theorem proving required at query time. This is done by using a classification scheme to reduce the number of specification matching proofs that are required to process a query. Components are classified by assigning features that correspond to necessary conditions implied by the component specifications. We show how this method of feature assignment can be used to approximate reusability relationships between queries and library components. The set of possible classification features are formally defined, permitting automation of the classification process. The classification process itself is made efficient by using a specialized theorem proving tactic to prove feature implication. The retrieval mechanism was implemented and evaluated experimentally using a library of list manipulation components. The results indicate a better response time than existing formal approaches. The approach provides higher levels of consistency and automation than informal methods, with comparable retrieval performance. [ABSTRACT FROM AUTHOR]

Synthesis of pragmatic systems from high-level specifications requires representation and application of both functional requirements and constraints. This work presents a language for representing requirements and constraints in VHDL design representations and a prototype care-based synthesis system. VSPEC is an annotation language for VHDL developed to support axiomatic representation of requirements for system synthesis. VSPEC descriptions serve as synthesis goals and verification criteria. A prototype case-based synthesis system is also presented that uses VSPEC requirements as goal statements and descriptions of potential solutions. This prototype system demonstrates how synthesis can be performed at the systems level and how constraints can be used to implement a simple concurrent engineering process. [ABSTRACT FROM PUBLISHER]

This article discusses the development of the Rosetta programming language for use in the system-level design of electronics. The elaboration of the semantics of this language by the Institute of Electrical and Electronic Engineers Inc. Computer Society (IEEE) P1699 Rosetta Working Group is described. The challenges of incorporating information on performance constraints and heterogeneous domain characteristics in the development of so-called system-on-chips (SoCs) are described. The characteristics of Rosetta, which is a heterogeneous, declarative, and formal language for engineering SoCs is noted. The development of the facet and domain based definition systems for this language is explored.

Relative cross sections for m-fold photoionization (m = 1,..., 5) of Fe3+ by single-photon absorption were measured employing the photon-ion merged-beams setup PIPE at the PETRA III synchrotron light source operated at DESY in Hamburg, Germany. The photon energies used spanned the range of 680–950 eV, covering both the photoexcitation resonances from the 2p and 2s shells, as well as the direct ionization from both shells. Multiconfiguration Dirac–Hartree–Fock (MCDHF) calculations were performed to simulate the total photoexcitation spectra. Good agreement was found with the experimental results. These computations helped to assign several strong resonance features to specific transitions. We also carried out Hartree–Fock calculations with relativistic extensions taking into account both photoexcitation and photoionization. Furthermore, we performed extensive MCDHF calculations of the Auger cascades that result when an electron is removed from the 2p and 2s shells of Fe3+. Our theoretically predicted charge-state fractions are in good agreement with the experimental results, representing a substantial improvement over previous theoretical calculations. The main reason for the disagreement with the previous calculations is their lack of inclusion of slow Auger decays of several configurations that can only proceed when accompanied by de-excitation of two electrons. In such cases, this additional shake-down transition of a (sub)valence electron is required to gain the necessary energy for the release of the Auger electron. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editors discuss various papers within the issue from the "15th Institute of Electrical and Electronics Engineers (IEEE) International Conference on Automated Software Engineering" that took place in Grenoble, France in September 2000.