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Process variations and physical defects can degrade the performance of a circuit, or even drastically affect its operation. It is therefore essential to verify the performance of each circuit produced in order to ensure the quality of manufactured devices shipped to the customers. This is the role of the testing process. This process represents a significant part of the total cost of an IC, especially for analog and RF circuits, whose performance must be measured with sophisticated and expensive test equipment. In order to reduce testing costs, one attractive solution is to adopt an indirect test strategy, which consists in measuring parameters that require only low-cost test resources and correlating these measurements, called Indirect Measurements (IMs), with the device specifications. This correlation is generally established using machine-learning algorithms during an initial learning phase. Then, during the production testing phase, every new device is evaluated using only the low-cost indirect measurements. While the indirect test strategy seems attractive, its deployment in an industrial context is viable only if sufficient test quality can be achieved. In this thesis, we have developed a methodology that permits to assist and guide the test engineer in its practical choices for an efficient implementation. Different aspects have been explored, such as the use of different types of regression models, the definition of pertinent metrics to evaluate the test efficiency, or the proposition of an original adaptive test flow in order to trade-off test quality and test cost. We have also proposed an adaptation of the indirect test strategy allowing to perform on-line monitoring of the device performance within its application. All results presented in this thesis have been evaluated using industrial test data on various case studies, which fully support the developed innovations.; Les variations de processus et les défauts physiques peuvent dégrader les performances d'un circuit, voire affecter considérablement son fonctionnement. Il est donc essentiel de vérifier les performances de chaque puce fabriquée afin de garantir la qualité des circuits envoyés aux clients. C'est le rôle du processus de test. Ce processus représente une part importante du coût total d'un circuit intégré, en particulier pour les circuits analogiques et RF dont les performances doivent être mesurées à l'aide d'un équipement de test sophistiqué et coûteux. Afin de réduire les coûts de test, une solution intéressante consiste à adopter une stratégie de test indirect, qui consiste à mesurer des paramètres ne nécessitant que des ressources de test peu coûteuses, et à corréler ces mesures indirectes avec les performances du circuit. Cette corrélation est généralement établie à l'aide d'algorithmes de machine-learning au cours d'une phase d'apprentissage initiale. Ensuite, pendant la phase de test de production, chaque nouveau circuit est évalué en utilisant uniquement les mesures indirectes peu coûteuses. Si cette stratégie de test indirect semble attrayante, son déploiement dans un contexte industriel n'est viable que si la qualité des tests est suffisante. Dans cette thèse, nous avons développé une méthodologie qui permet d'assister et de guider l'ingénieur de test dans ses choix pratiques pour une mise en œuvre efficace. Différents aspects ont été explorés, tels que l'utilisation de différents types de modèles de régression, la définition de métriques pertinentes pour évaluer l'efficacité des tests, ou la proposition d'un flot de test adaptatif original permettant de réaliser un compromis entre la qualité et le coût du test. Nous avons également proposé une adaptation de la stratégie de test indirect en vue d'un contrôle en ligne des performances du dispositif dans son application. Tous les résultats présentés dans cette thèse ont été évalués en utilisant des données de tests industrielles sur différents circuits RF, soutenant pleinement les innovations développées.

WOS:000423082000003 PubMed: 29264899 Introduction: This study evaluates the relationship between disease activity and neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in patients with chronic plaque psoriasis. Methods: Clinical and biochemical data were retrieved through retrospective examination of patients' and healthy subjects' medical records. NLR and PLR values were calculated from the hemogram results. This study included 46 patients (25 males, 21 females; 36.58 +/- 9.82 years) diagnosed with chronic plaque psoriasis and a control group of 46 healthy volunteers (21 males, 25 females; 34.02 +/- 8.41 years). Results: NLR and PLR were significantly elevated in patients with chronic plaque psoriasis (p = 0.0001 and p = 0.003, respectively). PASI was positively correlated with NLR, PLR, and serum CRP levels (r = 0.313, p = 0.034; r = 0.394, p = 0.017; r = 0.359, p = 0.014, respectively). Conclusion: NLR and PLR are low-cost tests that can be used to determine the severity of current systemic inflammation in patients with chronic plaque psoriasis.

AIM: To develop a fast, low-cost diagnostic strategy to identify single point mutations in highly variable genomes such as hepatitis C virus (HCV). METHODS: In patients with HCV infection, resistance-associated amino acid substitutions within the viral quasispecies prior to therapy can confer decreased susceptibility to direct-acting antiviral agents and lead to treatment failure and virological relapse. One such naturally occurring mutation is the Q80K substitution in the HCV-NS3 protease gene, which confers resistance to PI inhibitors, particularly simeprevir. Low-cost, highly sensitive techniques enabling routine detection of these single point mutations would be useful to identify patients at a risk of treatment failure. LightCycler methods, based on real-time PCR with sequence-specific probe hybridization, have been implemented in most diagnostic laboratories. However, this technique cannot identify single point mutations in highly variable genetic environments, such as the HCV genome. To circumvent this problem, we developed a new method to homogenize all nucleotides present in a region except the point mutation of interest. RESULTS: Using nucleotide-specific probes Q, K, and R substitutions at position 80 were clearly identified at a sensitivity of 10% (mutations present at a frequency of at least 10% were detected). The technique was successfully applied to identify the Q80K substitution in 240 HCV G1 serum samples, with performance comparable to that of direct Sanger sequencing, the current standard procedure for this purpose. The new method was then validated in a Catalonian population of 202 HCV G1-infected individuals. Q80K was detected in 14.6% of G1a patients and 0% of G1b in our setting. CONCLUSION: A fast, low-cost diagnostic strategy based on real-time PCR and fluorescence resonance energy transfer probe melting curve analysis has been successfully developed to identify single point mutations in highly variable genomes such as hepatitis C virus. This technique can be adapted to detect any single point mutation in highly variable genomes. Sí

This paper presents an efficient, low-cost, built-in test (BIT) circuit for radio frequency differential low noise amplifiers (DLNAs). The BIT circuit detects amplitude alterations at the outputs of the DLNA, due to parametric or catastrophic faults, and provides a single digital Pass/Fail indication signal. A triple modular redundancy approach has been adopted for the BIT circuit design to avoid possible yield loss in case of a malfunctioning test circuitry. The technique has been evaluated on a typical CMOS RF DLNA and simulation results are presented. Ieee Transactions on Circuits and Systems I-Regular Papers