Newest Methods and Approaches to Enhance the Performance of Optical Frequency-Domain Reflectometers.

In this review, we summarize the latest advances in the design of optical frequency-domain reflectometers (OFDRs), digital signal processing, and sensors based on special optical fibers. We discuss state-of-the-art approaches to improving metrological characteristics, such as spatial resolution, SNR, dynamic range, and the accuracy of determining back reflection coefficients. We also analyze the latest achievements in the OFDR-based sensors: the accuracy of spatial localization of the impact, the error in detecting temperatures, deformation, and other quantities, and the features of separate measurement of various physical quantities.

Azithromycin resistance in Escherichia coli and Salmonella from food-producing animals and meat in Europe.

Objectives: To characterize the genetic basis of azithromycin resistance in Escherichia coli and Salmonella collected within the EU harmonized antimicrobial resistance (AMR) surveillance programme in 2014-18 and the Danish AMR surveillance programme in 2016-19.

Methods: WGS data of 1007 E. coli [165 azithromycin resistant (MIC > 16 mg/L)] and 269 Salmonella [29 azithromycin resistant (MIC > 16 mg/L)] were screened for acquired macrolide resistance genes and mutations in rplDV, 23S rRNA and acrB genes using ResFinder v4.

An Optical Frequency Domain Reflectometer's (OFDR) Performance Improvement via Empirical Mode Decomposition (EMD) and Frequency Filtration for Smart Sensing.

We describe a method for reducing the cost of optical frequency domain reflectometer (OFDR) hardware by replacing two reference channels, including an auxiliary interferometer and a gas cell, with a single channel. To extract useful information, digital signal processing methods were used: digital frequency filtering, as well as empirical mode decomposition. It is shown that the presented method helps to avoid the use of an unnecessary analog-to-digital converter and photodetector, while the OFDR trace is restored by the equal frequency resampling (EFR) algorithm without loss of high resolution and with good measurement repeatability.

Improved mitochondrial coupling as a response to high mass-specific metabolic rate in extremely small mammals.

Mass-specific metabolic rate negatively co-varies with body mass from the whole-animal to the mitochondrial levels. Mitochondria are the mainly consumers of oxygen inspired by mammals to generate ATP or compensate energetic losses dissipated as the form of heat (proton leak) during oxidative phosphorylation. Consequently, ATP synthesis and proton leak thus compete for the same electrochemical gradient.

Aminoglycoside nephrotoxicity.

The main constraints to the administration of aminoglycosides (AG) are risks of nephrotoxicity and ototoxicity, which can lead to renal and vestibular failure. AG accumulation in the kidney may be related to the dosing schedule. As a result, administration of larger doses on a less frequent basis may reduce the drug accumulation in the renal cortex.

[PK/PD modeling of aminoglycoside nephrotoxicity].

Aminoglycosides are bactericidial antibiotics with a serum concentration-dependent activity. They are mainly eliminated by the kidneys and the main difficulty arising in clinical use is their uptake by the renal cortex which leads to nephrotoxicity. An ototoxicity is also reported.

[Toxicity and anti-tumour efficacy of oxaliplatin on Glasgow osteosarcoma induced in mice: a mathematical model].

To study time-scheduled regimens in the treatment of tumours by cytotoxic drugs delivered by IV injection, we propose a mathematical model of the action of a chemotherapy on the population of tumoral cells on the one hand, on a population of fast renewing healthy cells on the other hand. We chose for model parameter identification the treatment by oxaliplatin of Glasgow Osteosarcoma in mice.

Aminoglycoside dosages and nephrotoxicity: quantitative relationships.

Objective: To develop a model that relates the probability of occurrence of nephrotoxicity to the cumulative area under the curve (AUC) of amikacin serum concentration.

Design And Patients: This was a retrospective study of two groups of patients in whom nephrotoxicity was observed after administration of amikacin. The first group consisted of patients treated with once-daily administration (ODA) [n = 13].

Aminoglycoside nephrotoxicity: modeling, simulation, and control.

The main constraints on the administration of aminoglycosides are the risks of nephrotoxicity and ototoxicity, which can lead to acute, renal, vestibular, and auditory toxicities. In the present study we focused on nephrotoxicity. No reliable predictor of nephrotoxicity has been found to date.

Contribution of a mathematical modelling approach to the understanding of the ovarian function.

The biological meaning of folliculogenesis is to free fertilisable oocytes at the time of ovulation. We approached the study of the control of follicular development at the level of follicular granulosa cells, on the experimental as well as mathematical modelling grounds. We built a mathematical model allowing for the processes of proliferation, differentiation and apoptosis.

Time-patterned drug administration: insights from a modeling approach.

The physiological effects of a drug depend not only on its molecular structure but also on the time-pattern of its administration. One of the main reasons for the importance of temporal patterns in drug action is biological rhythms--particularly those of circadian period. These rhythms affect most physiological functions as well as drug metabolism, clearance, and dynamic processes that may alter drug availability and target cell responsiveness with reference to biological time.

Mathematical model of FSH-induced cAMP production in ovarian follicles.

During the terminal part of their development, ovarian follicles become totally dependent on gonadotropin supply to pursue their growth and maturation. Both gonadotropins, follicle-stimulating hormone (FSH) and luteining hormone (LH), operate mainly through stimulatory G protein-coupled receptors, their signal being transduced by the activation of the enzyme adenylyl cyclase and the production of second-messenger cAMP. In this paper, we develop a mathematical model of the dynamics of the coupling between FSH receptor stimulation and cAMP synthesis.

An illuminative example of nonlinear identification.

The parameter identification of a nonlinear system is often difficult to handle. Through the study of a particular nonlinear system with a limit cycle, corresponding to a biological system with an endogenous rhythm, we show that it is useful to take into account additional algebraic or geometric features of the system to achieve parameter identification.

Period shift induction by intermittent stimulation in a Drosophila model of PER protein oscillations.

PER protein circadian oscillations in Drosophila have been described by Goldbeter according to a five-dimensional model that includes the possibility of genetic mutation described by changing one parameter, the maximum degradation rate of the PER protein. Assuming that, in a mutant Drosophila this parameter is unreachable, we modify another parameter, the translation rate between the mRNA and the nonphosphorylated form of PER protein, by periodic intermittent activation or inhibition. We show how such a modification, simulated in the model by a periodic, on/off, piecewise constant stimulation (which increases or decreases this parameter) allows the entrainment of oscillations exactly at, or close to, a desired period.

Shift of a limit cycle in biology: From pathological to physiological homeostasia@f|.

Biological systems may show homeostatic behaviors that are similar to the ones of forced dynamic systems with a stable limit cycle. For a large class of dynamic systems, it is shown that a shift of a pathological limit cycle over the physiological limit cycle can never be executed by means of a control with a desired periodicity. The above statement shows that the only possibility is to reduce as much as possible the dimensions of a small residual limit cycle.

Nonlinear adaptive control of adrenal-postpituitary imbalances and identifiability analysis.

Adrenal-postpituitary imbalances express pathological evolutions of the nonlinear biological oscillator due to hormonal coupling between adrenocortical hormones and vasopressin. This system, based on agonistic-antagonistic equilibration, can be represented by a nonlinear model to be controlled in the pathological case, in order to reach a physiological state. The modeling introduced by E.

[Physiopathological approach to pathological hyperlactatemia in the diabetic patient. Value of blood metformin].

Type B lactic acidosis, or pathological hyperlactatemia (PHL), is defined by an arterial lactate level greater than 5 mmol X l-1. It is a known and severe complication of diabetes mellitus treated with biguanide hypoglycaemic agents, particularly phenformin which was taken off the French pharmaceutical market in 1977. Metformin, which remains the only biguanide hypoglycaemic agent currently prescribed in France, may also lead to this complication.

[Acute choriocapillaris occlusion in pregnancy and puerperium. Toxemias, thrombotic microangiopathies].

Six cases of gravidic toxemia (4) and thrombotic thrombocytopenic purpura (Moschowitz's disease) in puerperium with choriocapillaris occlusion, were examined. At the acute stage, the vision is improved, ophthalmoscopy of the fundus revealed cystlike bullous exudative subretinal with retinal detachment, yellowish spots (of retinal pigment epithelium) and often minimal localized arteriolar narrowing. The evolution included retina application pigmentary disturbances and Elschnig's spots.

[Acute edema of the lung in eclampsia].

In 6 cases of eclampsia in the course of pre and post-partum, we could observe neurological disorders associated with acute pulmonary oedema with acute respiratory distress occurring 5 to 72 hours after the first convulsive crisis. Hemodynamic check-up provided various results: 3 cases corresponded to A.P.

[Air embolus after Caesarean section (author's transl)].

This is case history of a primigravid woman on whom Caesarean section was carried out in normal conditions for fetal distress, the patient being placed in Trendelenburg position. After the abdomen had been closed there was a sudden collapse with cyanosis, right bundle branch block and then coma with hypertonicity, hyperreflexia and transitory hemiplegia. The only possible diagnosis that could be made was of air embolus following Caesarean section in the light of many investigations that were carried out and the improvement under hyperbaric oxygen treatment and the very irregular progress of the neurological symptoms.