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Feasibility checking is a step in manufacturing system engineering for verifying the normalization and effectiveness of a manufacturing system associated with a specific configuration of resources and processes. It enables factory operators to predict problems before operational time, thus preventing equipment and machinery accidents and reducing labor waste in physically organizing the shop floor. In Industry 4.0, feasibility checking becomes even more critical since emerging challenges, such as mass personalization, require reconfiguring work cells quickly and flexibly on demand. Regarding this need, digital twin technologies have emerged as an ideal candidate for practicing feasibility checking. Indeed, they are tools used to implement digital representations of manufacturing entities that can constitute a digital environment and context. Factory operators can test a manufacturing process within a digital environment in different contexts before the execution with physical resources. This approach currently receives significant attention from the manufacturing community; however, there is still a lack of sharing experiences to implement it. Thus, this paper contributes a methodology to engineer a digital environment and context for a manufacturing work cell using AAS digital twins and physics-based 3D digital twins technologies. Technically, this methodology is a specific case of N-DTs, a general methodology for engineering heterogeneous digital twins. The product assembly line case study, also presented in this paper, is a successful experiment applying the above contributions. The two methodologies and the case study can be helpful references for both public and private sectors to deploy their feasibility-checking frameworks and deal with heterogeneous digital twins in general.

Sensor-based digital systems for Instrumentation and Control (I&C) of nuclear reactors are quite complex in terms of architecture and functionalities. A high-level framework is highly required to pre-evaluate the system’s performance, check the consistency between different levels of abstraction and address the concerns of various stakeholders. In this work, we integrate the development process of I&C systems and the involvement of stakeholders within a model-driven methodology. The proposed approach introduces a new architectural framework that defines various concepts, allowing system implementations and encompassing different development phases, all actors, and system concerns. In addition, we define a new I&C Modeling Language (ICML) and a set of methodological rules needed to build different architectural framework views. To illustrate this methodology, we extend the specific use of an open-source system engineering tool, named Eclipse Papyrus, to carry out many automation and verification steps at different levels of abstraction. The architectural framework modeling capabilities will be validated using a realistic use case system for the protection of nuclear reactors. The proposed framework is able to reduce the overall system development cost by improving links between different specification tasks and providing a high abstraction level of system components.

Objective: To describe temporal profile of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) in patients with definite, relapsing multiple sclerosis (MS)., Background: Peripheral demyelinating neuropathy has been rarely reported in association with central nervous system demyelinating disorder indistinguishable from MS., Methods: In addition to usual diagnostic studies for CIDP and MS in all 5 patients, we studied proximal segments of nerves using deep tendon reflex latency measurements of biceps reflex, patellar reflex, and ankle reflex., Results: All patients with MS subsequently (4-22 years) developed definite CIDP. Two of these patients developed multiple cranial nerve and spinal root enhancement on subsequent imaging without new intraparenchymal enhancement after a diagnosis of CIDP. The deep tendon reflex latencies were prolonged at more than 2 sites in all patients. Cerebral spinal fluid protein increased (70 +/- 19 to 144.8 +/- 17.4 mg/dL, P = 0.0001) at time of diagnosis of CIDP. Clinical improvement was observed in all patients after intravenous immunoglobulin therapy., Conclusions: When patients with MS develop CIDP, manifestations of central and peripheral disease involvement seem to respond to intravenous immunoglobulin. These cases suggest that there may be common antigenic targets in central and peripheral nervous system in this subset of patients.

Small-fiber neuropathy (SFN) is diagnosed on the basis of clinical features and specialized tests of small-fiber function because standard nerve conduction studies are normal. Thus, the objective of this study was to determine the value of deep tendon reflex (DTR) latency measurement in the diagnosis of SFN in patients with preserved DTR on clinical examination. We prospectively examined electromyographic reflexes from the biceps brachii [biceps brachii reflex (BR)], patellar [patellar reflex (PR)], and ankle [ankle reflex (AR)] using a manually operated electronic reflex hammer attached to electromyography machine and recorded by means of surface electrodes in 18 patients with SFN and 38 controls. Intra- and inter-evaluator reliability was good (intraclass correlation coefficient: 0.80-0.91, p < 0.01). In controls, the latencies at all sites were correlated to the height (R= 0.6, p < 0.01). Compared with controls, in patients with SFN, the mean latency in milliseconds was prolonged at all sites (BR: 12.8 +/- 1.6 vs. 8.9 +/- 1.9, p < 0.01; PR: 23.0 +/- 5.8 vs. 17.4 +/- 2.4, p < 0.01; and AR: 34.5 +/- 4.8 vs. 30.0 +/- 2.4, p < 0.01). The sensitivity [61.1% (95% CI: 51-94.9)] and specificity [92% (95% CI: 73-97.3)] of BR latency were roughly equal to those of PR and AR. We conclude that DTR latencies were significantly abnormal in the majority of the patients with SFN, suggestive of subclinical involvement of large myelinated fibers. DTR latency measurement is a reproducible, valuable, sensitive tool in the evaluation of mild subclinical involvement of large fibers.

Primary hyperhidrosis is a neurogenic disorder of unknown cause characterized by excessive sweating in the palmar surface of the hands, armpits, groin and feet. In the course of a therapeutic trial for primary hyperhidrosis, 62 % of patients reported a positive family history. Examination of these pedigrees demonstrated a sibling recurrence risk of lambdas = 29-48 and an offspring recurrence risk of lambdao = 41-68 indicating that hyperhidrosis can be an inherited condition. The pattern of inheritance suggests an autosomal dominant mode of transmission with incomplete disease penetrance.

Background: Brain magnetic resonance (MR) imaging offers the potential for objective criteria in the differential diagnosis of multiple system atrophy with predominant parkinsonism (MSA-P) and Parkinson disease (PD), since it frequently shows characteristic abnormalities in patients with MSA-P and is believed to be normal in patients with PD., Objective: To determine concordance between clinical and MR imaging-based diagnoses of MSA-P and PD., Design: Two neuroradiologists identified and rated striatal and infratentorial abnormalities in 39 brain MR images and assigned a diagnosis of PD, MSA-P, or MSA with additional marked cerebellar ataxia (MSA-C)., Setting: Academic medical center., Patients: Thirty-nine patients with parkinsonism, including 21 with a clinical diagnosis of PD, 14 with MSA-P, and 4 with MSA-C., Results: All patients with MSA and 14 (67%) of 21 patients with PD had some abnormality on brain MR imaging. Brainstem atrophy was seen in patients with MSA-P and MSA-C. Putaminal atrophy was seen only in MSA-P. Putaminal hypointensity and lateral slitlike hyperintensity were seen in both PD and MSA-P but were always mild in PD. Cerebellar abnormalities, seen in all patients with MSA-C and 11 patients with MSA-P, were also identified in 6 patients with PD, albeit always rated as mild. Nonconcordance between clinical and radiological diagnosis occurred in 2 patients with PD, 5 with MSA-P, and 1 with MSA-C., Conclusion: Since several features on brain MR imaging are seen only in MSA-P, a simple diagnostic algorithm may improve the MR imaging diagnosis of MSA-P and PD.

Orthostatic intolerance is occasionally reported by patients with syringomyelia and is usually attributed to vestibular symptoms or neurogenic orthostatic hypotension. Postural tachycardia syndrome has not been previously described in syringomyelia. A patient with long-standing syringomyelia and a Chiari type I anomaly developed disabling "panic-like" attacks associated to orthostatic intolerance five years after posterior fossa decompression and shunting of the syrinx. A head-up tilt test showed an early phase of postural orthostatic tachycardia followed by progressive arterial hypotension and bradycardia as seen in neurally mediated syncope. A magnetic resonance imaging scan showed a collapsed syrinx from the 3rd cervical to the 12th thoracic vertebra without syringobulbia. Fludrocortisone and beta-blockers led to resolution of symptoms. Partial sympathetic denervation of the legs in syringomyelia might explain the occasional occurrence of postural tachycardia syndrome. Postural tachycardia syndrome may be included as a possible cause of orthostatic symptoms in syringomyelia patients.