Time-course effects of human recombinant luteinizing hormone on porcine Leydig cell specific differentiated functions

Polymerase chain reaction (PCR)-based assays were developed to detect virulent Rhodococcus equi in transtracheal aspirate samples from sick foals showing respiratory signs. An oligonucleotide primer pair from the sequence of the virulence-associated 15- to 17-kDa antigen gene of the virulence plasmid in virulent R. equi was used to amplify a 564 bp region by PCR, and the result was confirmed by Southern blot hybridization. No positive reaction was seen in DNA from 13 different microorganisms typically found in the respiratory tract. In tracheal aspirates seeded with virulent R. equi, a visible band could detect 10 to 10(2) bacteria per PCR assay (10(3) to 10(4)/ml of the aspirate). Virulent R. equi was demonstrated in 31 of 42 transtracheal aspirates by culture and colony blot analysis, whereas a positive PCR result was observed in only 12 of the 31 culture positive samples. To prevent false-negative results, two methods were developed: a nested PCR and a PCR in combination with enrichment cultures of aspirates in the selective medium to increase the number of bacteria to 10(4)/ml or more. All of the PCR-negative and culture-positive samples were positive by the two methods. These results indicated that PCR-based assays provide a specific and sensitive means to detect virulent R. equi in tracheal aspirates of foals, and they are more rapid than the routine culture procedures for the diagnosis of R. equi pneumonia in foals.     

“Sweet Spots” in Moderate Inversion for MOSFET Squarer Transconductors

Two "sweet spots" are analytically identified to enable MOSFET squarer differential transconductors to efficiently operate in moderate inversion. Measurements at low frequencies demonstrate the practicality of using moderate inversion when input signals are limited to about 200 mV_pk-pk. At the first sweet spot, very low distortion of significantly less than 0.5% total harmonic distortion is possible. For comparison, the sweet spot for the third harmonic is shown for the linear differential transconductor. This brief also discusses the effect of the variations in threshold voltage on the location of the sweet spots, and demonstrates that this sensitivity can be greatly reduced using an appropriate biasing circuit. The proposed approach is of particular interest for low voltage and low current squarer transconductance applications.     

LIFETIME PREDICTION ON Cr-Mo-V AND 316L STEELS UNDER THERMAL AND MECHANICAL CYCLING

The thermal-mechanical fatigue resistance of a Cr-Mo-V steel and a 316L steel under combined complex mechanical strain and temperature cycling has been evaluated. The applicability to thermal-mechanical lifetime prediction of several isothermal fatigue damage concepts is investigated. From a designer viewpoint, some predictions are well acceptable, in particular with the Degallaix thermal activation model for which a recent development is reported.     

Etude et réalisation de diviseurs de fréquence analogiques à diode à avalanche

In this paper the potential interest of analog avalanche diode frequency dividers is demonstrated. Their fundamental operation principle relies on the use of an idler signal. Experiments performed on avalanche diode frequency dividers with division ratios of 2, 3 and 4 in the centimeter wave range have pointed out the possibility of wide instantaneous bandwidth and interestingrf conversion efficiencies.     

A two chips set — full parallel process for framing equipment in sdh compatible radiolinks

ccitt has standardised a new synchronous interface named sdh (Synchronous Digital Hierarchy). Considering the importance of transmission-medium compatibility between radio and optical fibre systems, Alcatel Telspace has developed sdh based digital radio systems. In order to provide a direct access to all the section overhead bytes (soh) in the stm-1 frame and the insertion/extraction of radio overhead bytes for media specific usage, two cmos integrated circuits were designed, operating in a parallel process at 40 MHz data rate, in order to respect a full transparency criterion, necessary for a short synchronisation time on the whole radio link.     

Filtre correcteur de phase pour égaliseurs sous-optimaux

We propose a receiver structure intended for high bit rate transmissions. In order to ensure a good compromise between performance and complexity, the receiver is composed of a transversal phase- corrective filter followed by an equaliser, which takes only partially the channel impulse response into account. We propose a non-iterative technique to adjust the filter tap coefficients, based on the cepstral properties of a minimum phase response. The performance of the filter is evaluated and shown by simulating a transmission system including a multipath mobile radio channel, the filter and a dfse equaliser (decision feedback sequence estimator).     

A genetic algorithm for vehicle routing with backhauling

In this paper, a greedy route construction heuristic for a vehicle routing problem with backhauling is described. This heuristic inserts customers one by one into the routes using a fixed a priori ordering of customers. Then, a genetic algorithm is used to identify an ordering that produces good routes. Numerical comparisons are provided with an exact algorithm and with other heuristic approaches.     

To robotize chemistry laboratories. An example of organic synthesis: 2-Boc-amino-N-hydroxy-3-phenyl-propionamide

The paper describes the development of periodic modules used for the peptide synthesis of hydroxamic acid. A powder conveyor using the principle of positive weighing distribution is described. Purification is provided using automatic filtration and a liquid- liquid extraction module separation device. Device quality is improved using failure mode and effects analysis.     

GC sniffing analysis: olfactive intensity measurement by two methods

The intensity perceived by sniffing after GC elution of six volatile compounds was measured by ten judges using two pieces of apparatus: a PC mouse which is moved on a 60-cm length scale and a rheostat apparatus which measures the finger span. The choice of the components mixed was influenced by purity, elution time, presence in food and known Steven's slopes. The histograms obtained by summing the responses (determined by measuring the areas under the peaks) of ten people show no significant differences between the two pieces of apparatus. Histograms realised in parallel by Charm analysis with three other judges showed great differences between subjects. However, the mean of the three Charm analysis histograms was very similar to those histograms obtained with the two previously described pieces of apparatus. The same concentrations of ethyl butyrate, 3-methyl butanoic acid and 2,3,5-trimethyl pyrazine had the greatest odour intensity and thiophene, 2,6-dimethyl pyrazine and acetophenone had the lowest odour intensity.