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Modeling and design of CMOS ultra-high-frequency (UHF) voltage multipliers are presented. These circuits recover power from incident radio frequency (RF) signal and supply battery less UHF RF identification (RFID) transponders. An analytical model of CMOS UHF voltage multipliers is developed. It permits to determine the main design parameters in order to improve multiplier performance. The design of this kind of circuits is then greatly simplified and simulation time is reduced. Thanks to this model, a voltage multiplier is designed and implemented in a low-cost electrically erasable programmable read-only memory compatible CMOS process without Schottky diodes layers. Measurements results show communication ranges up to 5 m in the U.S. standard.

SUMMARY We solve by a finite difference method a system of simultaneous non-linear partial differential equations which modelizes the transfer of heat and mass when a fluid evaporates from the hot wall and condenses on the cold wall of an upright rectangular cavity. The need to verify a certain condition associating the physical parameters of the fluid for the existence of steady state solutions is proved.

Since 2003 we have tested the use of benthic foraminiferal faunas as bio-indicators of highly biodegradable oil-based drill fluids and cuttings. In this paper we present data for 4 sites off western Africa (Angola, Congo and Gabon), with water depths varying from 30 to 670 m. A very similar faunal response to environmental perturbation is found in these different environmental settings. In the close vicinity of the oil drill mud and fluids disposal, the combination of lowered bottom water oxygenation, the presence of toxic compounds and a general ecosystem enrichment leads to strongly impoverished faunas. More sensitive taxa become very rare in these areas. Moderately impacted sites are characterized by high to very faunal densities, and a strong dominance of opportunistic taxa, that are favored by the increased amount of organic matter in the benthic environment, resulting from the introduction of hydrocarbons. Beyond 500 m of the disposal sites, the faunas progressively become similar to the natural faunas; the relative frequency of opportunistic and stress-tolerant taxa drops to background values. Two foraminiferal indices are proposed that allow a quantitative evaluation of the impact of the oil drilling activities. A first foraminiferal index, that is based on the cumulative percentage of opportunistic and stress-tolerant taxa, is very effective in continental shelf settings. Severely polluted sites contain more than 70% index species, moderately impacted area between 50 and 70%. In slightly to non impacted sites, the percentage of index species drops from 50 to 20%. A shallow, 30 m deep, area in front of the Ogooué estuary reveals a high percentage of marker species at all investigated stations. This elevated percentage is caused by the presence of naturally eutrophicated conditions due to the supply of important amounts of nutrients and continental organic matter by river outflow. In this a particular setting, oil exploration activities appear to have only a minor environmental impact. At the 670 m deep upper slope site, the impacted stations are characterized by the progressive disappearance of the taxa that are most sensitive to ecosystem perturbation. The cumulative percentage of these taxa strongly decreases at the most impacted areas, which provides a very useful additional quantitative monitoring tool. The present data show that foraminiferal faunas are extremely powerful in monitoring the environmental impact of oil exploration activities. In the near future, the proposed foraminiferal indices will be tested in other areas, and the selected marker species will be formalized for different types of environmental settings, with different water depths and climatic conditions.

This paper presents a study and an optimization of a diode voltage multiplier including antenna matching problems. Results on this multiplier designed in a 0.18?m CMOS process are shown. It can power a RFID integrated circuit at a distance of 10 m with an efficiency of 30%. In this paper a simple analytical model of the complete tag including antenna and chip is presented. This model allows explaining results on crucial points of voltage multiplier design method. A test chip is designed and realized in collaboration with ST Microelectronics. Many measures are then realized and present good agreement with simulation results.

Blood cadmium level was determined in 29 nontreated hypertensive male subjects and 29 controls. All were individually matched for sex, age, and smoking habits. No differences were found between hypertensives (3.3 +/- 0.4 ng/ml) and normotensives (2.6 +/- 0.4 ng/ml).

Resume A propos de deux cas d'allergie respiratoire a la penicilline chez des preparateurs en pharmacie, et de deux cas chez des infirmieres, sont envisagees les consequences medicales et legales de cette affection. Il s'agit d'une maladie professionnelle a declaration obligatoire : s'il est deconseille d'admettre a ces postes de travail des sujets prediposes, cette mesure est insuffisante et doit etre associee a une plus grande attention portee aux problemes d'hygiene professionnelle. L'asthme par allergie a la penicilline peut parfaitement guerir a la suite d'un simple changement d'emploi. Mais l'un de nos malades se plaint d'une dyspnee qui meritera d'etre appreciee comme invalidite permanente partielle. L'allergie a la penicilline est rarement isolee et d'autres tests d'allergie immediate sont frequemment positifs : dans l'une de nos observations, l'arret du contact avec la penicilline a reduit considerablement les crises d'asthme, mais celles-ci n'ont ete supprimees que par un traitement complementaire de desensibilisation aux pneumallergenes domestiques, c'est dire la difficulte d'un diagnostic etiologique qui devra se baser avant tout sur des arguments cliniques. Les tests cutanes a la penicilline sont incertains et peuvent etre dangereux. Dans un cas, le test s'est montre negatif alors que l'evolution clinique etait absolument caracteristique. Dans un autre cas au contraire, le test fut exagerement intense, aggrave d'une crise d'asthme severe. Il faut insister sur le danger encouru par un sujet allergique a la penicilline et soumis sans precaution au cours d'une maladie intercurrente a un traitement pourtant bien banal par cet antibiotique ; tout sujet allergique a la penicilline doit etre prevenu qu'il risque, par simple ingestion de cette drogue, des accidents parfois mortels.

Hypoglycaemia occurred in two patients treated with perhexiline maleate. The responsibility of the medication is discussed in each case. Blood insulin levels were increased. Blood perhexiline levels decreased very rapidly in the first patient, though much more slowly in the second.

The value of electroencephalographic recordings during eserine treatment for overdosage with anticholinergics is discussed, based on the results obtained in 6 cases. The results were spectacular in three cases, and a partial improvement was noted in one other case (suicide attempts with overdoses of atropine compounds), but only a slight effect was observed in two patients (with overdose of neuroleptics). Three points have to be underlined concerning the E.E.G. recordings: --eserine did not cause supplementary E.E.G. changes;--with eserine, the paroxystic abnormalities observed during overdoses of atropine compounds and amitriptyline rapidly disappear;--with mixed overdoses (atropine, barbiturates, or minor tranquillizers), eserine has no effect against non-anticholinergic products. Therapy with eserine, however, is still limited in its indications because of its short period of activity, its side-effects, and the possible risks of cardiac or convulsant complications.

Out of 84 patients with colchicine poisoning hospitalised between 1966 and 1976, 11 died during the first 72 hours. Amongst the 73 survivors, 20 showed signs of marrow aplasia between the 3rd and 6th days, lasting on average 4 days. The average amount of colchicine ingested by these patients was 0.5 to 0.8mg/5g. Marrow aplasia was associated with: -- infectious episodes in all cases, -- haemorrhage in 50%, -- dilution hyponatraemia in 25% (but in 50 % of patients if those in renal failure are excluded), -- regressive polyneuropathy in 10 % of cases, -- secondary alopoecia in all cases, -- weight loss of more than 10 % of initial weight in 60 %. Two patients died as a result of septicaemia. This mortality rate of 10 per cent despite the brief duration of the aplasia and the absence of underlying haematological disease would appear to be related to the susceptibility of these poisoned patients to endogenous secondary infections, essentially intestinal in origin.

Transient episodes of the syndrome of inappropriate anti-diuresis developped in two severe colchicine poisonings. These are the first cases reported. On patient also developped a reversible periphal neuropathy. The similarity of such accidents with vicristine neuro-toxicity is emphasized.

The authors report on a case of lethal lactate acidosis during acute metformine and barbiturate poisoning. The study of energetic substrates and glucoregulation hormones demonstrated a blockade of hepatic gluconeogenesis.

Clinical, immunological, and functional investigations were conducted to study possible specific factors involved in the etiology of asthma in adults. The authors emphasize the frequency of positive skin, radio-immunologic and bronchial provocation tests for domestic pneumallergens in patients with common asthma, even those over 40 years of age. These cases improve in a protected environment and may benefit from immunotherapy. In patients with clinical manifestations suggesting possible occupational etiological factors the same tests can be used to diagnose the presence of a wide variety of vegetable or animal allergens. Tests involving exposing the bronchi to various chemical compounds used during working conditions (antibiotics, plastic precursors, metals, hair preparations) show that there exists a wide variety of causes. Systematic search for etiological factors is essential when investigating asthma in adults.

The authors present 16 cases of multifocal tuberculosis observed over a period of five years on a general medical unit. These cases almost all occurred in immigrants. (14 out of 16) with at least 2 localisations in 9 of them and sometimes 3 or more. The viscera usually affected were, in order, the liver, the lymph nodes, the lungs and pleura, the joints. They emphasise the mildness of the clinical symptoms, the rareness of lung involvement and, on the contrary, the constancy of hepatic involvement so that needle biopsy of the liver is essential in diagnosis.

During last 7 years, 13 cases of acute ethylene glycol poisoning have been observed with 4 fatal outbreaks. All cases--except one--were accidental. Six patients had drunk a mixture of antifreeze in water as they were lost in a desert. A patient who had taken 970 ml of ethylene glycol survived. In one case, death was due to irreversible brain damage; two other fatalities occurred from cardiorespiratory distress. CNS involvement was noticed in 8 cases and acute renal failure-constantly controlled-occurred in 9 patients. Post mortem examination has shown bi-refringent calcium oxalate crystals in both kidney and brain. Specific treatment with ethanol has been performed in 3 cases with ingestion of large amounts of toxic who were seen before definitive renal lesions have occurred. Emphasis is placed in symptomatic treatment including gastric lavage, extrarenal epuration and conservative management.