Background: In May 2007, a recently enhanced microbiological surveillance system reported 3 cases of Mycobacterium tuberculosis (TB) complex bacteremia among neonates from Nakhon Phanom province. An investigation was conducted to confirm the etiology and identify risk factors. Methods: We reviewed the medical records of the patients and their mothers, and observed vaccination, blood collection and laboratory procedures. Family members and health-care workers were screened with chest x-ray for TB disease. Repeat physical examination and chest x-ray were performed on the case-patients. Biochemical analysis and genotyping were performed on one available isolate Results: The 3 neonates were born to HIV-negative mothers in the same hospital April 2006 - March 2007; each received BCG vaccination within 24 hours of birth. Vaccines were from 3 different lots but were administered by the same nurse. Each neonate was discharged within 24 hours and returned to the hospital for routine hypothyroid screening 48 h later. At follow-up, each patient exhibited jaundice and two had fever. All were re-hospitalized and had hemocultures collected. Symptoms resolved and all were discharged without complication after 2–5 days. Isolates identified as M. tuberculosis complex were recovered from each patient's hemoculture after incubation for 28–32 days. Subsequent interviews and testing found no active TB cases among patients' mothers and close contacts. The neonates had normal chest x-rays, negative repeat hemocultures, and appeared healthy at the time of investigation. Genotyping of the only available isolate recovered from the initial hemocultures confirmed M. bovis BCG. Conclusion/interventions: We report the first 3 cases of transient BCG bacteremia after vaccination in otherwise healthy neonates in Thailand. Clinical implications of BCG bacteremia are unclear. As mycobacterial hemoculture is relatively new in this setting, further analysis and investigation are necessary to understand the scope and significance of BCG bacteremia.

The chemical composition of heavy liquids (b.p.>180°C) obtained by co-pyrolysis of polyolefins/wood biomass mixtures in autoclave conditions under inert atmosphere was investigated by FTIR, 1H NMR, GC-MS, high performance TLC combined with densitometry techniques. The preliminary separation of heavy liquids into different fractions by open LC and TLC methods had been used. Some perspectives of polymer and biomass thermal conversion during co-pyrolysis process were discussed.

The copyrolysis of wood biomass–polyolefins was carried out in a rotating autoclave. At 400°C, more than 50% (in mass) of final products are found in the liquid phase for a 1:1 (in mass) mixture. The obtained liquids are separated in a distillable liquids fraction and in an extracted liquids fraction. The first fraction can be fully characterised by gas chromatography/mass spectrometry. Only olefins, paraffins and some aromatics (benzene, toluene and xylene), issued from the polymers, are found in this fraction. The origin of the polymer plays the most important role in the chemical composition of this fraction. Some interactions with the solid issued from thermal degradation of the biomass are evidenced, for example by the presence of 2-alkenes with 3n carbon atoms. In the heavy liquids fraction, more than 80% (in mass) of the products are heavy olefins or paraffins. Schematically, we can explain the results of the copyrolysis experiments by: the biomass, whatever its origin, leads to solid, water and gas; polymer leads to liquid and gaseous olefins and paraffins; at a temperature lower than 400°C, the biomass reacts and during the pyrolysis at 400°C the formed solid evolves to act as a radical donor; assisted by radicals from biomass, polymer chain scission leads to the production of the light liquids; if the presence of biomass has an influence on the chemical composition of final products (particularly the light liquids fraction) their origin has, in general, only a limited effect.

The thermal behaviour of wood biomass and synthetic polymer mixtures was studied in a rotating autoclave. Beech wood, pine wood, cellulose, hydrolytic lignin, medium density polyethylene, isotactic and atactic polypropylene were selected as starting materials. The effects of reaction conditions, biomass and polymers’ origins on the degree of mixture conversion as well as on the yields of liquid and gaseous products were established and discussed. A preliminary thermogravimetric investigation has shown that biomass is thermally degraded at a lower temperature than the studied polyolefins. As described in the literature, independent thermal behaviors were, in all cases, observed for each component of biomass/plastic mixtures (1:1 weight ratio). Co-pyrolysis of the different types of natural and synthetic polymer mixtures in an inert atmosphere has led to high yield of light distillate fraction and benzene soluble products. The optimum temperature for biomass/plastic mixture conversion which corresponds to the maximum yield of light liquids was 400°C. The origins of both biomass and plastic had significant influences on the co-pyrolysis products’ distribution. In some cases non-additive effects were observed. This effect, generally, took place at biomass/plastic ratio lower then 1 (weight ratio) and resulted in high yields of distillate liquid fraction.

Two alternative methods, based on Thin-Layer Chromatography (TLC) with Fluorescence Scanning Densitometry have been developed for characterization of heavy liquids from copyrolysis of different kinds of biomass and plastics in autoclaves under inert atmosphere.

The part I of this work discusses the potentialities and limits of the in situ spectroscopic analysis of cellulose by Diffuse Reflectance Infrared Fourier Transform in an environment device. In this paper, we describe: the in situ evolutions of cellulose from 25 to 270°C under N 2 or air; the evolution of a partially thermolyzed cellulose residue during thermal treatment from 25 to 450°C and finally the oxidation in air of a cellulose char at 300°C. We observe a limited evolution of the cellulose below 270°C. Only some carbonyle groups issued from rearrangement of cellulose chains are formed. The thermal treatment of the thermolyzed residue leads to a progressive aromatization of the solid between 270 and 450°C. The oxidation in air induces the formation of oxygenated groups (carbonyles, carboxylic acids, lactones) and proceeds by reaction on both aliphatic and aromatic sites. Some dehydration of carboxylic groups to anhydrides are observed.

The main topic of this work is the diffusion behaviour in a standard polyimide film of current use (Kapton), under and out of irradiation, of metallic coatings with different reactivity (Cu, Ni, Ti) deposited by sputtering. The analysis of diffusion profiles has been performed by backscattering spectrometry in association with cross-sectional electron microscopy, which allow to connect the diffusion behaviour to the microscopic structure of the metal/Kapton interface. Generally speaking, the study under thermal annealing shows the importance of peculiarities of commercial polymers. In particular, incorporated additives are liable to modify their surface characteristics and, as a consequence, diffusion. So, unlike observations in model polyimides, we show that even weakly reactive metals do not diffuse into the polymer. Besides, there exists an energy threshold of Ar+ used for sputtering, above which Cu layers become very stable and so come up to industrial requirements. The study under irradiation gives evidence for Cu diffusion under heavy ions irradiation, resulting in 15 nm mean radius spherical clusters inside the modified polymer. This fast diffusion is interpreted as a consequence of injection of metal atoms by nuclear collisions into the polymer and diffusion as a concomitant effect of temperature. This study provides also the opportunity to show dramatic radiation-induced effects in Kapton, more particularly a large modification of mechanical (observed by nanoindentation) and optical properties with the loss of more volatile elements (H, N, O).

An algorithm has been developed in order to determine by Rutherford backscattering spectrometry (RBS) the characteristic parameters of laterally non-uniform targets as a complement to the more qualitative information obtained by microscopy. It allows access to the statistical distribution of the non-uniform property of the sample, which can be represented in the form of a histogram and used for further simulation. The applicability and sensitivity of this method are discussed on the basis of two practical examples. The reliability of the results is checked by comparison with SEM and TEM observations. The possibility of extending the application of the method to other types of lateral non-uniformity and other techniques of ion beam analysis is also discussed.

Copper and titanium layers deposited on a polyimide film (Kapton) have been studied under two adverse conditions: annealing and irradiation. Metals were deposited by sputtering at room or elevated temperatures (from 251 to 410 degrees C). Rutherford backscattering spectrometry and cross-sectional transmission electron microscopy studies have shown copper layer unwetting for annealing temperatures below the Kapton glass transition temperature (T-g approximate to 360 degrees C). We have observed copper cluster formation on the polyimide surface by surface diffusion that impedes the diffusion in depth. When the annealing temperature is above T-g, copper clusters formation occurs together with immersion under polyimide surface until 80 nm depth. The microscopy study of a copper layer deposited at room temperature shows the evolution of copper/Kapton interface after an irradiation by 300 keV krypton ions at a fluence of 3 x 10(16) ions/cm(2). We observe a large modification of the polymer surface up to 500 nm in depth, as compared with the nonirradiated surface, with a succession of more contrasting blocks at the surface. RES, EDS and ERD analyses indicate the modified polymer layer is impoverished in oxygen, nitrogen and hydrogen, which seems to confirm the formation of new carbonaceous materials. Electron microscopy shows clearly the presence of spherical copper clusters inside the modified film with an average size (10 nm radius) that agrees with the known existence of voids in Kapton. The copper distribution observed by microanalysis is in agreement with the quantitative results that we obtain by RES. Our studies of oxidized titanium layers have shown that, contrarily to copper layers, the oxidized titanium/Kapton systems do not experience changes after irradiation and annealing neither above T-g nor below T-g.