Mobile phone use and temporal skin heat sensation

International audienceEpidemiological investigation of mobile phone (MP) users reported symptoms of discomfort feeling, warmth behind/around or on the ear and heat sensation of the cheek. These symptoms may be due to thermal insulation, conduction of the heat produced in the phone by the battery currents and running of the radiofrequency (RF) electronic circuits, and electromagnetic field (EMF) energy absorbed by the user's head. Using a Luxtron 790 fiberoptic thermometer we measured the temperature of the temporal skin due to GSM 1800 MHz MP radiated power (125 mW). We suppressed the EMF exposure by switching the RF signal from the antenna to a 50 O load. The ambient air temperature was 23°C and the MP was held in the normal position of use for 30 minutes to reach the thermal steady state. With a switched off MP, the increase in skin temperature was statistically significant 1.88°C. When MP was switched on, the increase was 2.93°C in reception mode, 3.29°C in emission mode without load and 3.31°C in emission mode with load. The temperature difference with or without load was not significant (tl7 = 0.707; p = 0.489), which means that the contribution of EMF absorption to skin heating is negligible. The result suggests that the heat sensations reported by the MP users are exclusively caused by thermal insulation and heat conduction from MP associated with long calling time

Thyroïde accessoire ectopique : une observation clinique inhabituelle: Ectopic accessory thyroid gland: an unusual case report

The Ectopic accessory thyroid is a rare embryologic malformation defined as the presence of thyroid tissue outside of its normal position. The coexistence between an accessory thyroid and a thyroid gland in its normal position is exceptional. We report a case of an elderly patient who underwent a surgery for a heteromultinodular goiter with incidental intraoperative discovery of an ectopic accessory thyroid nodule in the anterior mediastinum. L’ectopie thyroïdienne est une malformation embryologique rare qui est une présence de tissu thyroïdien en dehors de sa position normale, la thyroïde accessoire avec une glande thyroïde en place est exceptionnelle. Nous rapportons un cas d’une patiente âgée opérée pour un goitre hétéromultinodulaire avec découverte fortuite per-opératoire d’un nodule thyroïdien accessoire ectopique dans le médiastin antérieur

Fistule cholécysto-biliaire dans le cadre de syndrome de Mirizzi: Cholecysto-biliary fistula in the context of Mirizzi syndrome

Le syndrome de Mirizzi est une étiologie rare de l’ictère rétentionnel suite à une compression de la voie biliaire principale par un calcul enclavé dans le collet vésiculaire ou dans le canal cystique, cette compression peut évoluer vers l’érosion de la paroi du canal hépatique commun et provoquer la formation d’une fistule cholécysto-biliaire. Son diagnostic préopératoire repose sur l’imagerie et surtout la cholangio-IRM, mais la découverte per opératoire de ces dégâts biliaires nécessite une prise en charge chirurgicale appropriée. Nous rapportons le cas d’une patiente de 42 ans, opérait pour un syndrome de Mirizzi et dont l’exploration chirurgicale découvrait une large fistule cholécysto-biliaire traitait par un drainage externe par un drain de kehr et une cholécystectomie antérograde avec suites post opératoires favorables. Mirizzi syndrome is a rare etiology of retentional jaundice caused by a compression of the bile duct by an enclaved stone in the gallbladder neck or in the cystic duct. This compression may progress to erosion of the wall of the common hepatic duct and lead to the formation of a cholecystic-biliary fistula. Its preoperative diagnosis is based on imaging and especially cholangio-MRI, but the peroperative discovery of this biliary damage requires appropriate surgical management. We report the case of a 42-year-old patient, operated for Mirizzi syndrome and whose surgical exploration discovered a large cholecysto-biliary fistula treated by external drainage through a kehr drain and an anterograde cholecystectomy with favourable postoperative follow-up

A combined study of heat and mass transfer in an infant incubator with an overhead screen

The main objective of this study is to investigate the major physical processes taking place inside an infant incubator, before and after modifications have been made to its interior chamber. The modification involves the addition of an overhead screen to decrease radiation heat losses from the infant placed inside the incubator. The present study investigates the effect of these modifications on the convective heat flux from the infant’s body to the surrounding environment inside the incubator. A combined analysis of airflow and heat transfer due to conduction, convection, radiation and evaporation has been performed, in order to calculate the temperature and velocity fields inside the incubator before and after the design modification. Due to the geometrical complexity of the model, Computer-Aided Design (CAD) applications were used to generate a computer-based model. All numerical calculations have been performed using the commercial Computational Fluid Dynamics (CFD) package FLUENT, together with in-house routines used for managing purposes and User-Defined Functions (UDFs) which extend the basic solver capabilities. Numerical calculations have been performed for three different air inlet temperatures: 32, 34 and 36ºC. The study shows a decrease of the radiative and convective heat losses when the overhead screen is present. The results obtained were numerically verified as well as compared with results available in the literature from investigations of dry heat losses from infant manikins

Thermal skin damage and mobile phone use

International audienceMobile phone "cell phone" use has dramatically increased over th last decade, but doubts remain over its safety. Epidemiological investigation of mobile phone (MP) users reported symptoms of discomfort feeling, warmth behind/around or on the ear and heat sensation of the cheek. These symptoms may be due to thermal insulation, conduction of the heat produced in the phone by the battery currents and running of the radiofrequency (RF) electronic circuits, and electromagnetic field (EMF) energy absorbed by the user's head. Using a Luxtron 790 fiberoptic thermometer we measured the temperature of the temporal skin due to GSM 1800 MHz MP radiated power (125 mW). To perform a sham exposure, we suppressed the EMF exposure by switching the RF signal from the antenna to a 50 Ohms load. The ambient air temperature was 23°C, the relative humidity was 50 +- 10 %, the air flow rate in the room was 0.01 m.s-1 (natural convection) and the MP was held in the normal position of use "cheek position" (CENELEC Standard 50361) for 30 minutes to reach the thermal steady state. With a switched off MP, the increase in skin temperature was statistically significant 1.88°C. When MP was switched on, the increase was 2.93°C in reception mode, 3.29°C in emission mode without load and 3.31 °C in emission mode with load. The temperature difference with or without load was not significant (t = 0.707; p = 0.489), which means that the contribution of EMF absorption to skin heating is negligible. The highest temperature increases detected during these experiments (TSkin = 37.1°C ~ core temperature) are in the environmental range and are lower than those physiologically experienced by the surface skin during hot summer days. No skin damage by thermal insuit is experienced for Tskin < 44°C, whereby a pain sensation replaces the feeling of temperature elevation in humans. This local skin temperature increase will cause thermoregulation responses. The skin blood vessels will be dilated and skin will be wet. The result suggests that the heat sensations reported by the MP users are exclusively caused by thermal insulation and heat conduction from MP associated with long calling time. No thermal skin damage can be suspected using MP in normal use

Intérêt de la bandelette urinaire dans le dépistage des bactériuries asymptomatiques chez le patient diabétique.

Objectifs: Le patient diabétique est prédisposé aux infections urinaires souvent asymptomatiques ou de symptomatologie atypique. Il était question dans cette étude, de mettre le point sur l’apport de la bandelette urinaire dans l’exclusion des bactériuries asymptomatiques chez ces sujets. Patients et méthodes : Les prélèvements urinaires de 427 malades externes (247 hommes, 180 femmes, moyenne d’âge : 59 ans), consultant entre mai et octobre 2012 ont été étudiés par examen cytobactériologique des urines (ECBU) et par bandelette réactive urinaire. Les résultats des bandelettes urinaires ont été confrontés aux données des ECBU au moyen de l’analyse statistique des performances diagnostic (sensibilité, spécificité, valeurs prédictives, rapports de vraisemblance). De plus, une estimation du ratio cout-efficacité était réalisée. Résultats : L’étude a enregistré 39 infections (9 %) parmi lesquelles quatre bandelettes faussement négatives. En cas de négativité des deux tests : leucocytes estérases et nitrites, la valeur prédictive négative a été de 98% [IC 95 % : 96,9–99,5]. Le ratio cout-efficacité incrémental est estimé à 852,7 DH par bactériurie asymptomatique dépistée. Conclusion : La bandelette urinaire est performante dans le dépistage des bactériuries asymptomatiques chez le sujet diabétique. En plus, de considérables économies peuvent être réalisées. Il a été donc décidé de supprimer l’ECBU systématique en faveur du dépistage par bandelette urinaire