Search results for "periodic"
showing 10 items of 769 documents
Sustained oscillations in the MAP kinase cascade.
2016
Abstract The MAP kinase cascade is a network of enzymatic reactions arranged in layers. In each layer occurs a multiple futile cycle of phosphorylations. The fully phosphorylated substrate then serves as an enzyme for the layer below. This paper focuses on the existence of parameters for which Hopf bifurcations occur and generate periodic orbits. Furthermore it is explained how geometric singular perturbation theory allows to generalize results from simple models to more complex ones.
Biotechnological Agents for Patients With Tumor Necrosis Factor Receptor Associated Periodic Syndrome-Therapeutic Outcome and Predictors of Response:…
2021
Objective: To describe the role of biotechnological therapies in patients with tumor necrosis factor receptor associated periodic syndrome (TRAPS) and to identify any predictor of complete response.Methods: Clinical, laboratory, and therapeutic data from 44 Caucasian TRAPS patients treated with biologic agents were retrospectively collected in 16 Italian tertiary Centers.Results: A total of 55 biological courses with anakinra (n = 26), canakinumab (n = 16), anti-TNF-α agents (n = 10), and tocilizumab (n = 3) were analyzed. A complete response was observed in 41 (74.5%) cases, a partial response in 9 (16.4%) cases and a treatment failure in 5 (9.1%) cases. The frequency of TRAPS exacerbation…
Vacuolated PAS-Positive Lymphocytes on Blood Smear: An Easy Screening Tool and a Possible Biomarker for Monitoring Therapeutic Responses in Late Onse…
2018
Background: Primary aim was to investigate the diagnostic value of PAS-positive vacuolated lymphocytes on blood smear in Late Onset Pompe Disease (LOPD) patients and, secondly, to evaluate its potential utility in monitoring treatment effects.Methods: We examined blood smear of 26 LOPD patients. We evaluated 10 treated and 16 untreated LOPD patients. Among the latter group, 7 patients later initiated ERT and were tested again 6 months after start. Blood smear was also sampled from 82 controls and 19 patients with other muscle glycogenoses (MGSDs). PAS staining was used to evaluate: (1) presence of lymphocytes with glycogen-filled vacuoles, (2) quantification of vacuolated lymphocytes.Result…
Back pain in a group of computer workers assessed in a physiotherapy unit
2021
BACKGROUND: Modern society work implies computer-based activities generating back pain because of prolonged sitting positions and non-ergonomic postures. OBJECTIVE: The aim of the study was to analyse the back-pain characteristics in a group of office workers in comparison with potential risk factors. METHODS: The design of the study was retrospective; a group of 109 computer workers with back pain was selected from a private physiotherapy unit between Jan 2018 - Dec 2019. Anthropometric, occupational and behaviour data, symptoms, the diagnosis on the first visit, previous medical diagnosis and specific physical activities were collected from medical records. RESULTS: The studied group (res…
Contributions to Branch-and-Price-and-Cut Algorithms for Routing Problems
2019
This article deals with new exact branch-and-price-and-cut algorithms for the solution of routing problems. Specialized methods for the pickup-and-delivery problem (PDP), the truck-and-trailer routing problem (TTRP), the periodic vehicle routing problem (PVRP) and a service network design and hub location problem (SNDHLP) are presented. We develop a new technique for the acceleration of bidirectional labeling algorithms by a dynamic choice of the merge point. Moreover, for variants of the PDP, the bidirectional labeling can be effectively applied for the first time. In the TTRP, we model the extension to a 2 days planning horizon and the consideration of a quantity-dependent transfer time. …
Branch-and-Price-and-Cut for the Periodic Vehicle Routing Problem with Flexible Schedule Structures
2019
This paper addresses the periodic vehicle routing problem with time windows (PVRPTW). Therein, customers require one or several visits during a planning horizon of several periods. The possible visiting patterns (schedules) per customer are limited. In the classical PVRPTW, it is common to assume that each customer requires a specific visit frequency and offers all corresponding schedules with regular intervals between the visits. In this paper, we permit all kinds of schedule structures and the choice of the service frequency. We present an exact branch-and-price-and-cut algorithm for the classical PVRPTW and its variant with flexible schedules. The pricing problems are elementary shortes…
The periodic rural postman problem with irregular services on mixed graphs
2019
Abstract In this paper, we deal with an extension of the rural postman problem in which some links of a mixed graph must be traversed a given number of times over a time horizon. These links represent entities that must be serviced a specified number of times in some subsets of days (or periods) of the time horizon. The aim is to design a set of minimum-cost tours, one for each day/period of the time horizon, that satisfy the service requirements. We refer to this problem as the periodic rural postman problem with irregular services (PRPP–IS). Some practical applications of the problem can be found in road maintenance operations and road network surveillance, for example. In order to solve …
Preparation and structural characterization of organotin(IV) complexes with ligands containing a hetero {N} atom and a hydroxy group or hydroxy and c…
2005
AbstractTwenty-two n-butyltin(IV) and t-butyltin(IV) complexes of ligands containing an –OH (–C@O) group or –OH and –COOHgroups and an aromatic {N} donor atom were prepared by metathetical reactions. On the basis of the FT-IR and Mo¨ssbauer spec-troscopic data, molecular structures were assigned to these compounds. The binding sites of the ligands were identified by means ofFT-IR spectroscopic measurements, and it was found that in most cases the organotin(IV) moiety reacts with the phenolic form ofthese ligands. In the complexes with –OH and –COOH functions, the –COOH group is coordinated to the organotin(IV) centres in amonodentate manner. The 119 Sn Mo¨ssbauer and the FT-IR studies suppor…
Dataa näkyvissä: Läpinäkyvyys algoritmien ja datan journalistisessa hyödyntämisessä
2021
Läpinäkyvyyden käsite on noussut keskeiseksi viestinnän, median ja politiikan tutkimuksessa sekä viestinnän ja politiikan käytäntöjen eettisessä arvioinnissa. Läpinäkyvyyttä on esitetty keinoksi ylläpitää ja kasvattaa luottamusta journalistista työtä ja sen tuotteita kohtaan interaktiivisessa media- ja viestintäympäristössä. Tiedontuotannon ja päätöksenteon perustuessa yhä enemmän dataan ja sen prosessointiin läpinäkyvyys on noussut keskeiseksi käsitteeksi myös algoritmisen päätöksenteon kohdalla. Tässä artikkelissa tarkastelemme läpinäkyvyyden roolia dataa ja algoritmeja sekä journalismia koskevassa keskustelussa ja esitämme mahdollisuuksia dataan ja algoritmeihin tukeutuvan journalismin l…
Existence de points fixes enlacés à une orbite périodique d'un homéomorphisme du plan
1992
Let f be an orientation-preserving homeomorphism of the plane such that f-Id is contracting. Under these hypotheses, we establish the existence, for every periodic orbit, of a fixed point which has nonzero linking number with this periodic orbit.