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The wide implementation of different regional anesthesia techniques is also actual in pediatric anesthesiology. Using modern methods of regional anesthesia (RA) and modern local anesthetics is a new level in development of pediatric anesthesiology. This article is about advantages of regional pediatric anesthesia in intra- and post-surgery pain management and analgesia. We analyse the techniques of spinal and epidural anesthesia, as well as their varieties such as unipolar spinal block and caudal anesthesia, compare their advantages and disadvantages. Some more techniques such as paravertebral block, TAP-block are considered as an alternative to epidural anesthesia. Methods and possibilities of ilioinguinal, iliohypogastric and TAP-blocks are also mentioned here. The use of the above-mentioned methods allows to reduce the use of narcotic analgesics and hypnotics and, as a consequence, reduces their systemic effects on the child’s body. These methods are safer for use, since they allow you to plan a safe anesthetic for each child and minimize complications., Широкое внедрение различных методов регионарной анестезии не могло обойти и детскую анестезиологию. Использование современных методик РА и новых местных анестетиков является, бесспорно, новой ступенью развития детской анестезиологии. В данной статье мы хотим осветить преимущества регионарной анестезии у детей, как для интра-, так и для постоперационного обезболивания. Рассмотрим методики выполнения, преимущества и недостатки спинальной и эпидуральной анестезии, а также их разновидности, такие как униполярный спинальный блок и каудальная анестезия, соответственно. Паравертебральный блок и ТАР-блок как альтернативы эпидуральной анестезии. А также методики и возможности применения илиоингвинального, илиогипогастрального и ТАР-блоков. Использование вышеназванных методик позволяет уменьшить использование наркотических анальгетиков, гипнотиков и соответственно снизить их системное воздействие на организм ребенка., Широке впровадження різноманітних методів регіонарної анестезії не могло оминути й дитячу анестезіологію. Використання сучасних методик РА та нових місцевих анестетиків є, безперечно, новою сходинкою розвитку дитячої анестезіології. У даній статті ми хочемо висвітлити переваги регіонарної анестезії у дітей як для інтра-, так і для постопераційного знечулення. Розглянемо методики виконання, переваги й недоліки спінальної та епідуральної анестезії, а також їхні різновиди, такі як уніполярний спінальний блок та каудальна анестезія, відповідно; паравертебральний блок і ТАР-блок як альтернативи епідуральній анестезії; а також методики та можливості застосування іліоінгвінального, іліогіпогастрального і ТАР-блоків. Використання вищеназваних методик дозволяє зменшити використання наркотичних анальгетиків, гіпнотиків та відповідно знизити їх системний вплив на організм дитини.

We lay out the thesis that modern supersonic air transportation has the best chance of realization by commencing with small aircraft. A possible implementation path is described with reference to the Aerion AS2 supersonic business jet. Further, the paper entails an overview on the economic and operational challenges of supersonic airliners.

3d metal K-shell X-ray absorption spectra of perovskites with the composition La1-xCaxCoO3-delta (x=0, 0.2, 0.4, 0.5, 0.6, 0.8), La1-xSrxCoO3-delta (x=0, 0.1, 0.2, 0.3, 0.4, 0.5) and La1-xSrxFeO3-delta (x=0, 0.2, 0.4, 0.5, 0.6, 0.8) are compared on the basis of pre-edges, white line features and extended fine structures. The measurements were performed at 300 K and for La1-xCaxCoO3-delta also at temperatures as low as 10-20 K. Going to low-temperature the measurements indicate an increase in t(2g)* and a decrease in e(g)* orbital occupancy, which is most accentuated in the LaCoO3 sample. Virtually no Co K-edge shift was observed for the La1-xCaxCoO3-delta and La1-xSrxCoO3-delta compounds and the Co-O distances are also not significantly reduced when La3+ is partially substituted by Ca2+ or Sr2+. From the pre-edge features of these perovskites we are tended to conclude that the t(2g)* orbitals are less, and the e(g)* orbitals are more occupied with increasing x in the Ca and Sr substituted compounds, whereas the total d-electron density is not changing. These results indicate that cobalt prefers a valence state of 3(+) in these Co perovskites. This could also be confirmed with iodometric titrations. The Fe perovskites behave differently. In contrast to the Co perovskites, for La1-xSrxFeO3-delta perovskites the Fe K-edge is shifted, the pre-edge features intensity is increasing and the Fe-O bond length is decreasing with increasing x. The valence states of the iron in the La1-xSrxFeO3-delta perovskites in fact increase as much as x increases. (C) 2011 Elsevier Inc. All rights reserved.

Es wird uber einen Patienten mit einer konstitutionellen Deletion am kurzen Arm von Chromosom 4 [del(4)(p16)] und den typischen klinischen Symptomen des Wolf-Hirschhorn-Syndroms (WHS; OMIM # 194190), wie Hypertelorismus, zeltformiger Mund, tief sitzende Ohren, valvulare Aortenstenose, Hodendysplasie und Hypospadie, berichtet. Die psychomotorische Entwicklung wurde durch eine ausgepragte muskulare Hypotonie, beidseitige Innenohrschwerhorigkeit und BNS-Epilepsie kompliziert. Da eine fruhkindliche BNS-Epilepsie laut Literatur bei bisher etwa 50 von 300 Patienten mit WHS beschrieben wurde, sollte das Wolf-Hirschhorn-Syndrom in die Differenzialdiagnose von fruhkindlichen Epilepsiesyndromen, die mit zusatzlichen Dysmorphiezeichen einhergehen, miteinbezogen werden.

We used thermogravimetric hydrogen reduction and iodometric titration to determine the bulk valence state of cobalt in Co-perovskites containing surface carbonate hydroxide or hydroxyl groups. It could be shown that thermogravimetric hydrogen reduction experiments are very sensitive to volatile surface groups, but due to their volatility, they can be specified and the bulk valence state of cobalt can still be deduced from these experiments. The iodometric titration is less sensitive to small volatile surface impurities, but precaution has to be taken that oxygen or iodine does not escape from the solution during dissolution of the sample. Best results were obtained if the sample was titrated during dissolution in a closed argon floated titration apparatus. We tested the two methods using LaCoO3 perovskite as a sample with a known valence state. Both methods delivered satisfactory results, and the valence state could be determined with an accuracy of better than 1%.

The ion exchange occurring between a poly(vinylferrocene) (PVF) film and the bathing solution during the oxidation−reduction process was studied by probe beam deflection (PBD) in aqueous and nonaqueous media. In nonaqueous media the results for different electrolyte salts indicate that anions are exchanged. In aqueous media, the ion exchange is strongly affected by the anion present in the solution. In tetrafluoroborate and hexafluorophosphate solutions, cation exchange is observed while in toluenesulfonate solution anion exchange in observed. In perchlorate and trifluoromethanesulfonate solutions a mixed mechanism involving cation and anion exchange is observed. Expulsion of cations precedes anion insertion on oxidation. The ion flux is not affected by the pH (in the range from 1 to 7) or the electrolyte concentration (between 0.1 and 4 M). The kind of ion exchanged appears to correlate with the type of interaction (attractive or repulsive) between redox centers inside the film seen from voltammogram sha...

For the development of a long-lived, electrically rechargeable zinc–air battery the structure and wettability of pasted zinc electrodes were optimized. Pasted zinc electrodes containing 1 to 10% cellulose but having almost the same nominal capacities were prepared and tested in zinc/oxygen cells. The effect of discharge rate on cell voltage and delivered capacity, as well as the maximum power, were measured. Furthermore, cell charge–discharge behaviour and cycle life were examined. After different times of operation, the porosity and the pore size distribution of the pasted zinc electrodes were measured by means of mercury porosimetry. The cycle life and peak power drain capability of the Zn/oxygen battery could be substantially improved by the addition of 10wt% cellulose to the pasted zinc electrode.

A bipolar filter press-type electrically rechargeable Zn/O2 battery has been developed. Reticulated copper foam served as substrate for the zinc deposit on the anodic side, and La0.6Ca0.4CoO3-catalysed bifunctional oxygen electrodes were used on the cathodic side of the cells. The 100cm2 unit cell had an open circuit voltage of 1.4V (O2) in moderately alkaline electrolyte. The open circuit voltage and the peak power measured for a stack containing seven cells were sim 10V and sim 90W, respectively. The current-potential behaviour was determined as a function of the number of bipolar cells, and the maximum discharge capacity was determined at different discharge rates.

The measured cyclic voltammogram of a polyacetylene-coated electrode bathed in an electrolyte solution was simulated numerically for various scan rates. The model used accounts for a modified Butler-Volmer-type heterogeneous kinetics at the electrode surface including a lateral interaction term which effects the observed hysteresis behavior. Within the polymer an electron flux obeying Ohm`s law as well as electrolyte diffusion and migration is considered and Poisson`s equation holds for electroneutrality. Donnan partition kinetics describes the flux and potential at the interface between the polymer and diffusion layer. Electrolyte diffusion is considered in the diffusion layer. Much effort has been invested in conducting polymers in order to develop a rechargeable polymer battery.

International audience; Morphology control of the active layer in bulk hetero junction devices is essential for obtaining high-energy conversion efficiency. For poly(3-hexylthiophene) (P3HT)-[6-6]-phenyl-C"6"1-butyric acid methyl ester (PCBM) based organic photovoltaic cells, the low performance is assigned to the formation of PCBM aggregates, whose process has not been clearly established. In this work, we have investigated P3HT:PCBM composite films, which were prepared by dissolving the mixture in co-solvents of chlorobenzene and toluene of different proportions. The solvents have been chosen for their close boiling points and for their different polarities, which impact on the solubility of organic components. Optical (absorption, photoluminescence), surface (Atomic Force Microscopy, X-ray photoelectron spectroscopy) and structural (X-ray diffraction) characterization techniques have been performed on blend films prepared by co-solvents. The result analysis has clearly pointed out the key role of the PCBM solubility on the film organization. Conversely, the regioregularity of P3HT would not influence the film morphology when using dominant chlorobenzene solvents but strongly affected it when using dominant toluene solvents.

The effect of counterion type on the ac impedance and linear sweep voltammetry response of a film consisting of Os(bpy) 2 (bpy indicates 2,2'-bipyridal) coordinatively bound in PVP (poly(4-vinylpyridine)) was investigated. Four acids were used at 0.1 M in the aqueous bathing electrolytes: hydrochloric, perchloric, trifluoroacetic, and toluenesulfonic. Analysis of the mobile ion concentrations in the film showed that protons were rejected from the film via Donnan exclusion, mating anions and hopping electrons the only two charge carriers. Ac impedance spectra revealed that, even with the largest counterion studied, ion transport was much faster than electron hopping

Proton exchange membranes were prepared by simultaneous radiation grafting of styrene onto Teflon-FEP films and subsequent sulfonation. Degrees of grafting from 13 to 52% were obtained. FTIR-ATR in combination with FTIR measurements show a homogeneous distribution of polystyrene across the grafted film. Water uptake after swelling in boiling water and specific conductivity of the sulfonated membranes were determined. The strong decrease in specific resistivity with increasing degree of grafting is due to an increasing proton mobility, reflected by an increasing hydration of the sulfonic acid groups. For degrees of grafting higher than 30% specific resistivity values at low as 2 Ω-cm (20°C) are measured, compared with a value of 12 Ω-cm for Nafion 117 membranes.

Metal/air batteries provide high specific energy and consist of inexpensive and environmentally benign materials. They have begun to penetrate the market of portable power sources and offer great promise for transportation applications. In this review, we first discuss the basic aspects of metal/air batteries, then concentrate on the Zn/air system as the most promising metal/air battery. The Zn/air systems have important advantages due to the excellent electrochemical properties of metallic zinc, which include a high overpotential towards hydrogen evolution. This implies that Zn/air batteries with aqueous electrolytes can be electrically recharged, that zinc from spent batteries can be regenerated by electrolysis in aqueous systems, and that mechanically rechargeable Zn/air batteries (arrangements resembling fuel cells) can be realized with aqueous electrolytes. Advances in the development of Zn/air battery components are reviewed and the state of the art of electrically and mechanically rechargeable Zn/air systems is described in detail. An overview of industrial developments in zinc/air battery systems and the nominal performance of available products is included. Practical specific energies in the range of 90–120 Wh kg−1 have been reported for electrically rechargeable Zn/air batteries, about twice as much for mechanically rechargeable systems. Significant progress has been made concerning the cyclability of the electrically rechargeable Zn/air system, by utilizing pasted zinc electrodes and graphitized carbon for the bifunctional oxygen diffusion electrodes. Cycle lives in the range of 200–450 cycles have been achieved. Keywords: metal/air batteries; zinc/air batteries; zinc electrodes; pasted zinc electrodes; zinc slurry electrodes; oxygen electrodes; oxygen diffusion electrodes; bifunctional oxygen electrodes; catalysts/ oxygen electrodes; catalysts

Electron hopping in redox polymer-modified electrodes requires coincident ion movement to maintain electroneutrality, and transport effects can arise due to either process. In this paper, the equation for diffusion/migration by electron hopping is used with the classical Nernst-Planck equation for mobile ionic species to rigorously model the ac impedance response of a redox-site-containing polymer attached to an electrode and bathed by a binary aqueous electrolyte. The theory also includes the effect of polymer redox-site interactions. Donnan exclusion is assumed, permitting only one mobile ion in the film

Rechargeable zinc–air batteries are promising power sources that use inexpensive and environmentally benign materials. The high specific charges of zinc and oxygen electrodes offer the possibility to design batteries with exceptionally high specific energy. In addition, zinc–air batteries are aqueous nonhazardous systems, which is an important issue for many applications. This review discusses the basic aspects of rechargeable zinc–air batteries, recent advances in the development of battery components, and the state-of-the-art of rechargeable zinc–air battery systems. Energy efficiency and the cycle life at high power still require improvement. On the contrary, cycle lives of several hundred cycles with 60% energy efficiency have been demonstrated at low power, and practical specific energies in the range of 90–120 Wh kg−1 have been achieved. Unfortunately, rechargeable zinc–air batteries are not yet available commercially.

The increasing contribution of dispersed and renewable energy sources (DER) to the peak power balance of up to 60 % and the goals of the European Community for the year 2010 require innovative approaches in order to maintain the sustainability of the power supply. Sustainability in this context requires that DER significantly support system services like frequency control, power balance, voltage control or supply restoration after failures. For this, remote information exchange with the respective DER units will become necessary. Consequently, interoperable and scaleable communication solutions play a key role for sustainability in power systems with an increasing share of DER The "network for energy and communication" (NEaC) which was founded by the German Federal Ministry of Education and Research, is a consortium that elaborates requirements, specifications, systems, standards and related technologies for inter-networked DERs. A communication network with diverse physical communication media is considered for a typical medium/low voltage network with industrial, commercial, rural and household customers each with typical load profiles. A variety of DER units like wind power plants, fuel cells, photovoltaic plants or CHP units is considered. It is demonstrated how an optimized communication network, complying with technical and economical requirements, can be realized. NEaC strongly supports international standards and shows that IEC 61850 fulfils all related selection criteria for DER communication systems.

Although AML cells are highly sensitive to cytotoxic agents the majority of AML patients relaps after conventional chemotherapy due to the persistence of minimal residual disease. Leukemia cell derived dendritic cells (DCs) generated by in vitro differentiation of AML cells may be useful for anti-leukemia vaccination strategies.

International audience

From 1981 to 1988, 138 patients with hiatal hernia were treated surgically at our centre. Twenty-one (mean age 76.6 years, 17 women, four men) had an associated intrathoracic gastric volvulus. Eleven patients (mean age 73.2 years), of whom eight were asymptomatic, had an elective procedure. Ten patients (mean age 80.3 years) had emergency surgery, six for acute complications of the volvulus (five cases of strangulation and one of perforated ulcer) and four because of other, unrelated causes of acute abdomen. There were four deaths after operation, all in the emergency surgery group. Four other patients had significant morbidity, all in the emergency group. In the elective cases, all hernias were easily reduced. In one emergency case a gastrotomy was necessary for decompression, and in another gastrectomy was necessary because of gastric gangrene. Our results indicate the need for elective intervention when intrathoracic gastric volvulus is first diagnosed.

Aluminium alloys were tested in Al/O2 cells with strongly acidic electrolytes containing minor amounts of chloride ions. The faradaic efficiency, the maximum discharge capacity and the peak power of various Al/O2 cells were evaluated. The temperature dependence of the faradaic efficiency was measured for an Al/O2 cell over the temperature range from 15 to 50°C. With a zinc-containing aluminium alloy, a faradaic efficiency of 84% and a cell voltage of 1.6 V at open circuit and 0.7 V at 100 mA cm−2 could be reached. The highest peak power 120 mW cm−2, was obtained with an Al-Zn/Sn alloy. On the basis of the solubility of the anode products in the electrolyte, a limiting specific energy of 70 Wh kg−1 was estimated. The cell voltage depends on the Al-alloys and on the catalyst used in the oxygen electrode. The cell voltage could be increased by about 200 mV when replacing the Pt-catalysed oxygen electrode with a noble-metal-free (CoCAA/DCD) electrode.

A filter-press-type Al/O2 battery with bipolar assembly of the electrodes was developed. The current-voltage curves and power output of monopolar and of bipolar batteries containing one to four cells were measured in alkaline (4 m NaOH and 7.5 M KOH) and acidic (3 m H2SO4 + 0.041 m HCl) electrolytes. The unit cell had an open circuit voltage of 1.85 V in alkaline media and 1.3 V in acidic media. The single bipolar unit delivered a maximum power of about 7.5 W (75 mW cm−2) at 0.7 V. The stack (four cells) had a maximum power of 30 W in 4 m NaOH and 35 W in 3 m H2S04 + 0.04 m HCl. The power output of the bipolar stack determined experimentally for different external loads could be described using the model of an electric equivalent circuit.

Eleven patients underwent left transthoracic reoperation for recurrence of hiatus hernia after previous surgical treatment. A left thoracic approach was chosen because of three cases of major obesity, three patients with multiple previous laparotomies, three recurrences of para-esophageal hernia, three associated dyskinetic disorders of lower esophagus. Ten patients underwent a Belsey Mark IV procedure with three myotomies of lower esophagus and one pyloroplasty. One patient underwent a Collis-Belsey procedure. Operative mortality was zero. Every patient had been followed up with a mean of 31 months. Ten patients have a good result. One patient had a massive recurrence of gastroesophageal reflux after Belsey Mark IV which led to a duodenal diversion 18 months later. Although the abdominal approach allows easier dissection of lower esophagus and complementary procedures to the lower esophagus. Results are as good as those of the abdominal approach.

We performed a two-step polymerase chain reaction (PCR) to detect bcr-abl-specific mRNA in 440 peripheral blood and/or bone marrow samples of 30 chronic myeloid leukemia (CML) patients (mean 15, range 2-50 samples) following non T-cell-depleted allogeneic (n = 28) or syngeneic (n = 2) bone marrow transplantation (BMT). Median follow-up after BMT is 40 months (range 2-116 months), the median observation time 29 months (range 2-40 months). In 15 patients (50%), bcr-abl-specific mRNA could be detected following BMT. Bcr-abl positivity was rare in patients who were in hematological remission for at least 40 months (2/11). In five patients, PCR positivity was observed only once; all five patients are in complete hematological remission. Ten patients showed bcr-abl specific mRNA in two or more consecutive samples. Hematological relapse occurred in five of the latter patients. Bcr-abl positivity preceded hematological relapse in all cases. Bcr-abl positivity was detected more frequently in patients without graft-versus-host disease (GVHD) (11/15), than in patients with GVHD (4/15) (p0.02). Our data indicate that transient bcr-abl positivity is not usually followed by hematological relapse, while patients, who are positive in serial samples have a high risk of relapse.

Short and long term results of 52 derivative-surgical procedures (43 choledocho-duodenal and 9 hepatico-jejunal with 45 latero-lateral and 7 termino-lateral approaches) were examined. The procedures were performed on patients with benign bilio-digestive conditions: 46 cases of lithiasis, 2 of which were sump syndromes after latero-lateral derivations, and 6 cases of chronic pancreatitis. Several patients were in poor pre-operative condition, which may have influenced postoperative mortality rates (6%). Morbidity was 15 per cent. Four patients (8%) without anastomotic stenosis had infections of the hepatobiliary system within four years of choledochoduodenostomy. In some cases of benign bilio-digestive lesions, derivative surgery is the procedure of choice, being preferable to endoscopic sphincterotomy. In derivative surgery, a termino-lateral approach has better results than a latero-lateral approach. Furthermore, due to the risk of stasis following a choledochoduodenostomy, a hepaticojejunostomy may be preferable.

We report a series of 12 kidneys harvested from 8 brain-dead patients with unstable haemodynamic condition after in situ renal cooling using the double balloon technique. Material and technique are described. The outcome of the renal grafts is known at 3 and 12 months: 92 percent of the renal grafts were functioning at 3 months and 87 percent at 12 months. The mean serum creatinine level of the recipients with functioning graft was 135 mumol/l at 3 months and 113 mumol/l at 12 months. These results suggest that the in situ renal cooling technique makes it possible to obtain kidneys under unstable haemodynamic conditions.

Pathogeny of thoracic esophageal diverticuli, divided into parabronchial and epiphrenic, appears to have been modified by development of functional esophageal motility measurement. We present 23 patients with epiphrenic diverticuli and 3 with parabronchial diverticuli (15 male and 11 female with a mean age of 61 years). Twenty-four underwent surgery: 4 isolated diverticulectomy, 7 diverticulectomy and associated myotomy, 5 myotomy alone, 3 antireflux procedure alone. Three patients required esophagectomy for carcinoma in a diverticulum, for a huge diverticulum adherent to the inferior pulmonary vein. One patient presenting with perforation of a carcinomatous diverticulum in the pleura was treated with pleurotomy and has died. No fistula has been notified. Long term results had been analysed with a mean follow up of 4 years. Special attention has been reported on development of gastro-esophageal-reflux. The finding of a thoracic diverticulum requires evaluation by barium swallow, fibroscopy and functional test which should indicate the operation required. Long term analysis should include functional manometric evaluation and a pHanalysis as long term results are reduced by the appearance of gastro-esophageal-reflux.

A model of deterministic and stochastic behaviour of electrode—electrolyte interface where electroactive species are strongly adsorbed is presented. It leads to the current—voltage curve, the electrochemical impedance and the electrochemical noise. An experimental study of an electrode coated with a thin film of redox polymer shows a good agreement between the model predictions and the experimental data, and leads to an experimental confirmation of the Fluctuation—Dissipation theorem (Nyquist theorem) for this system at thermodynamic equilibrium. The kinetic parameters are deduced from the impedance.

In a coordinated research programme sponsored by the Internation Atomic Energy Agency, the frequencies of chromocomal aberrations induced in peripheral blood lymphocytes (in vitro) by 250 kV X-rays at low doses (0.4, 1, 2, 3, 5, 10 and 30 rad) were determined. Blood from 2 donors was used to conduct one master experiment at these dose levels. The culture time used was 48 h and all samples including the controls were processed according to a standard protocol. The coded slides were scored by investigators from 10 participating laboratories. The main results are the following: (1) the frequencies of all types of chromosome aberrations at 0.4 rad are significantly lower than the control values; (2) there is no increase in the frequencies of dicentrics up to 2 rad and in those of terminal deletions up to 5 rad; (3) the mean frequencies of all aberrations considered together are not significantly different from one another at 1,2 and 3 rad ( P = 0.05); and (4) over the entire dose range the dose-effect relationship is clearly non-linear. A fit of these data to a linear quadratic model ( E ( D ) = c + αD + βD 2 ) showed that the observed total aberration frequencies at doses 1,2,3 and 5 rad are below the curve defined by the model. The deviations can be explained by an altered kinetics of aberration production at very low doses probably due to DNA repair mechanisms operating in these cells.

Al/Cl2 cells were built using a coaxial cylindrical cell arrangement with cylindrical porous graphite chlorine electrodes and 99.5% Al anodes (cylindrical rods). The electrolyte used was a slightly acidic aqueous NaCl solution containing small amounts of In3+ and Hg2+ as additives. The cells have an open-circuit voltage of 2.6 V and a maximum power density of 55mW cm−2 at a cell voltage of 1.6V with a Faradaic efficiency of 65–70%. A battery consisting of seven cells connected in parallel delivered a maximum power of about 15W.

The activity of aluminum chloride dissolved in molten LiClKCl eutectic has been determined by emf measurements of an Al/Cl 2 cell (AlCl 3 formation cell) containing the ternary system as the electrolyte. The temperature range examined was 350–500°C. The concentration range of dissolved AlCl 3 has an upper limit where the system separates into two phases. Good theoretical estimates were obtained for the partial pressures of the components in the vapor phase in equilibrium with the melt when simple thermodynamic assumptions were used as a starting point. These results were compared with a number of values determined experimentally in the ternary system and with values deduced from results obtained for LiClAlCl 3 and KClAlCl 3 binary systems.

A modified enrichment-serology (MES) procedure was used to reduce the time necessary for salmonella analysis. Naturally contaminated samples of soy products were preenriched in 1% proteose peptone for 6 h at 37 degrees C followed by inoculation into tetrathionate broth for 18 h at 37 degrees C. Two drops of the tetrathionate sample were inoculated into M broth. After incubation at 37 degrees C for 6 h, 0.85 ml of the mixture was formolized, and 0.1 ml of polyvalent H antiserum was added. After incubation in water bath at 50 degrees C for 1 h, the appearance of a typical floccular flagellar precipitate was observed in tubes positive for salmonellae. Over 3,000 samples were subjected to standard biochemical and serological procedures, and the results were compared with those of the MES method with a 96.7% correlation. Eleven of the samples (0.3%) were false-negative with the MES procedure, and 3% were false-negative with the U.S. Food and Drug Administration Bacteriological Analytical Manual procedure. The 3% negative samples by this latter procedure were subsequently found to be positive by the MES procedure. The MES procedure reduced the time required for salmonella analysis from 4 days to 32 h.

The reaction Cl2+2e ⇔ 2Cl− has been studied by transient electrochemical techniques on a vitreous carbon electrode in fused alkali chlorides. Two regimes have been detected: for small overpotentials the electrode response obeys the classical laws of linear diffusion, for larger overpotentials the electrode behaviour involves the gas coming from the bubbles. A model is presented to describe these mechanisms. Four steps are considered: dissolution of chlorine around a gas bubble, diffusion in the electrolyte, charge transfer and chloride ion migration. The first step is always rapid. The influence of the three other steps is examined. It is indicated that the largest part of the reaction occurs near the triple contact interface. At the very extremity of the tip, charge transfer is the primary limiting factor: it is considered that over a distance of a few atomic diameters the mass transport is very rapid. At the largest distances the diffusion of dissolved chlorine constitutes the main limiting factor. The ohmic drop due to the electrical resistance of the electrolyte remains small. The influence of the interfacial tension and of the shape of the bubbles are predicted. The non-stationary situation is also examined in order to take into account the size variation of the gas bubbles during transient conditions.