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Abstract This paper is a contribution to the development of microwave plasma-based technology aimed at efficient hydrogen (H2) production from a so-called synthetic biogas, considered a mixture of methane (CH4) and carbon dioxide (CO2), which can contain up to 70% CH4. In this work, we tested the performance of a waveguide-supplied metal cylinder-based microwave plasma source (MPS) operating at 915 MHz at atmospheric pressure as a tool for the efficient production of H2 in the steam reforming of the synthetic biogas. The test showed that the steam reforming of the synthetic biogas could be carried out under a wide range of working parameters without soot formation and extinction of the microwave discharge. We found that there is a minimal H2Osteam consumption rate for a given CH4 input volume content, which ensures stable operation of the MPS (no soot). The experiments did not show that increasing the amount of H2Osteam rate above the minimal value for a given CH4 input volume content results in an increase in the H2 production rate, energy yield, CH4 conversion degree, and H2 output concentration. To describe the MPS performance, which also takes into account a factor of the utilization of the CH4 feedstock, we introduced a new parameter, called an energy–CH4 feedstock consumption yield. The best results in terms of the H2 production rate, the energy yield, and the CH4 conversion degree were 239 g[H2]/h 36.8 g[H2]/kWh, and 74.3%, respectively. This shows that the application of the steam reforming, instead of the dry reforming, resulted in a 1.5-fold increase of the H2 production rate and the corresponding energy yield.

Background: Postnatal corticosteroids (PC) are widely used in very preterm infants. International reports and national multicenter trials describe a marked variability across countries and inter-sites, in the use of PC. Few information is available on therapeutic indications and prescription characteristics of PC.Aim: The main objective of this study was to describe the exposure to PC in a large cohort of preterm infants born at less than 32 weeks of gestation, according to the prescription data of 41 tertiary-care NICUs in France. Secondary objectives were to describe therapeutic indications, day of life (DOL) of the first exposure, route of administration, duration, cumulative dose for each drug, and differences in exposure rates across centers.Methods: We conducted a prospective observational cohort analysis from January 2017 to December 2021, in 41 French tertiary-care NICUs using the same computerized order-entry system.Results: In total, 13,913 infants [birth weight 1144.8 (±365.6) g] were included. Among them, 3633 (26.1%) were exposed to PC, 21.8% by systemic and 10.1% by inhaled route. Within the study population, 1,992 infants (14.3%) received the first corticosteroid treatment in the first week of life and 1641 (11.8%) after DOL 7. The more frequent indications were prevention and/or treatment of bronchopulmonary dysplasia, and arterial hypotension. Hydrocortisone was the more often prescribed molecule. For systemic PC the first exposure occurred in mean at DOL 9.4 (±13.5), mean duration of treatment was 10.3 (±14.3) days, and the cumulative dose (expressed as the equivalent dose of hydrocortisone) was in median [IQR] 9.0 [5.5–28.8] mg/kg. For inhaled PC, the first exposure occurred in mean at DOL 34.1 (±19.7), and mean duration of treatment 28.5 (±24.4) days. The exposure rate ranged from a minimum of 5% to a maximum of 56% among centers, and significantly increased over the study period (p < 0.0001).Conclusion: In this French cohort of very preterm infants, around one patient out to five was exposed to PC during hospital stay in the NICU. The exposure occurred early, starting from the first week of life. Exposure rate widely varied among centers. Pharmacoepidemiology studies are useful to increase knowledge on corticosteroid utilization patterns in preterm infants.

This work presents experimental results on the energy efficiency in hydrogen production using atmospheric microwave plasma (915 MHz) through steam reforming of ethanol. Ethanol was chosen as a liquid hydrogen carrier due to its high hydrogen atom content, low cost, and wide availability. The experimental work began with the maximization of an energy efficiency of the used microwave plasma source. The process of maximization involved determining a position of a movable plunger that ensures the most efficient transfer of microwave energy from a microwave source to the generated plasma in the microwave plasma source. The aim of the investigations was to test the following working conditions of the microwave plasma source: absorbed microwave power P A by the generated plasma (up to 5.4 kW), the carrier gas volumetric flow rate (up to 3900 Nl/h), and the amount of the introduced ethanol vapours on the efficiency of hydrogen production (up to 2.4 kg/h). In the range of tested working conditions, the highest energy yield for hydrogen production achieved a rate of 26.9 g(H 2 )/kWh, while the highest hydrogen production was 99.3 g(H 2 )/h., (© 2024. The Author(s).)

This paper presents the results of experimental investigations of the plasma surface modification of a poly(methyl methacrylate) (PMMA) polymer and PMMA composites with a [6,6]-phenyl-C61-butyric acid methyl ester fullerene derivative (PC 61 BM). An atmospheric pressure microwave (2.45 GHz) argon plasma sheet was used. The experimental parameters were: an argon (Ar) flow rate (up to 20 NL/min), microwave power (up to 530 W), number of plasma scans (up to 3) and, the kind of treated material. In order to assess the plasma effect, the possible changes in the wettability, roughness, chemical composition, and mechanical properties of the plasma-treated samples' surfaces were evaluated by water contact angle goniometry (WCA), atomic force microscopy (AFM), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The best result concerning the water contact angle reduction was from 83° to 29.7° for the PMMA material. The ageing studies of the PMMA plasma-modified surface showed long term (100 h) improved wettability. As a result of plasma treating, changes in the samples surface roughness parameters were observed, however their dependence on the number of plasma scans is irregular. The ATR-FTIR spectra of the PMMA plasma-treated surfaces showed only slight changes in comparison with the spectra of an untreated sample. The more significant differences were demonstrated by XPS measurements indicating the surface chemical composition changes after plasma treatment and revealing the oxygen to carbon ratio increase from 0.1 to 0.4.

The specific properties of an atmospheric pressure plasma make it an attractive tool for the surface treatment of various materials. With this in mind, this paper presents the results of experimental investigations of a polycarbonate (PC) material surface modification using this new type of argon microwave (2.45 GHz) plasma source. The uniqueness of the new plasma source lies in the shape of the generated plasma-in contrast to other microwave plasma sources, which usually provide a plasma in the form of a flame or column, the new ones provides a plasma in the shape of a regular plasma sheet. The influence of the absorbed microwave power and the number of scans on the changes of the wettability and morphological and mechanical properties of the plasma-treated PC samples was investigated. The mechanical properties and changes in roughness of the samples were measured by the use of atomic force microscopy (AFM). The wettability of the plasma-modified samples was tested by measuring the water contact angle. In order to confirm the plasma effect, each of the above-mentioned measurements was performed before and after plasma treatment. All experimental tests were performed with an argon of flow rate up to 20 L/min and the absorbed microwave power ranged from 300 to 850 W. The results prove the capability of the new atmospheric pressure plasma type in modifying the morphological and mechanical properties of PC surfaces for industrial applications.

The innate immune system encodes cytosolic Nod-like receptors (NLRs), several of which activate caspase 1 processing and IL-1beta and IL-18 secretion. Macrophages respond to Salmonella typhimurium infection by activating caspase 1 through the NLR Ipaf. This activation is mediated by cytosolic flagellin through the activity of the virulence-associated type III secretion system (T3SS). We demonstrate here that Pseudomonas aeruginosa activates caspase 1 and induces IL-1beta secretion in infected macrophages. While live, virulent P. aeruginosa activate IL-1beta secretion through caspase 1 and Ipaf, strains that have mutations in the T3SS or in flagellin did not. Ipaf-dependent caspase 1 activation could be recapitulated by delivering P. aeruginosa flagellin to the macrophage cytosol. We examined the role of Naip5 in P. aeruginosa-induced caspase 1 activation by using A/J (Naip5-deficient) compared with C57BL/6 and BALB/c (Naip5-sufficient) macrophages and observed that A/J macrophages secrete IL-1beta in response to P. aeruginosa, S. typhimurium, and Listeria monocytogenes infection, as well as in response to cytosolic flagellin, but at slightly reduced levels. Thus, Ipaf-dependent detection of cytosolic flagellin is a conserved mechanism by which macrophages detect the presence of pathogens that use T3SS.

Here we present a finished sequence of human chromosome 15, together with a high-quality gene catalogue. As chromosome 15 is one of seven human chromosomes with a high rate of segmental duplication, we have carried out a detailed analysis of the duplication structure of the chromosome. Segmental duplications in chromosome 15 are largely clustered in two regions, on proximal and distal 15q; the proximal region is notable because recombination among the segmental duplications can result in deletions causing Prader-Willi and Angelman syndromes. Sequence analysis shows that the proximal and distal regions of 15q share extensive ancient similarity. Using a simple approach, we have been able to reconstruct many of the events by which the current duplication structure arose. We find that most of the intrachromosomal duplications seem to share a common ancestry. Finally, we demonstrate that some remaining gaps in the genome sequence are probably due to structural polymorphisms between haplotypes; this may explain a significant fraction of the gaps remaining in the human genome.

Chromosome 14 is one of five acrocentric chromosomes in the human genome. These chromosomes are characterized by a heterochromatic short arm that contains essentially ribosomal RNA genes, and a euchromatic long arm in which most, if not all, of the protein-coding genes are located. The finished sequence of human chromosome 14 comprises 87,410,661 base pairs, representing 100% of its euchromatic portion, in a single continuous segment covering the entire long arm with no gaps. Two loci of crucial importance for the immune system, as well as more than 60 disease genes, have been localized so far on chromosome 14. We identified 1,050 genes and gene fragments, and 393 pseudogenes. On the basis of comparisons with other vertebrate genomes, we estimate that more than 96% of the chromosome 14 genes have been annotated. From an analysis of the CpG island occurrences, we estimate that 70% of these annotated genes are complete at their 5' end.

The human genome is by far the largest genome to be sequenced, and its size and complexity present many challenges for sequence assembly. The International Human Genome Sequencing Consortium constructed a map of the whole genome to enable the selection of clones for sequencing and for the accurate assembly of the genome sequence. Here we report the construction of the whole-genome bacterial artificial chromosome (BAC) map and its integration with previous landmark maps and information from mapping efforts focused on specific chromosomal regions. We also describe the integration of sequence data with the map.

Cephalosporin C was produced by a highly productive strain of Cephalosporium acremonium under industrial production conditions by fed-batch cultivation in a 40-l stirred-tank reactor using a complex medium containing 50 g l-1 peanut flour. The influence of dissolved oxygen concentration (pO2, DOC), which was maintained at different constant levels between 5 and 40% of its saturation value, during the production phase by means of a parameter-adaptive pO2-controller, on the cephalosporin C biosynthesis, was investigated. The concentrations of cephalosporin C (CPC) and its precursors penicillin N (PEN N), deacetoxycephalosporin C (DAOC), and deacetylcephalosporin C (DAC) were monitored by on-line HPLC. The concentrations of amino acids, valine (VAL), cysteine (CYS), alpha-amino-adipic acid (alpha-AAA), the dipeptide alpha-amino-adipyl-cysteine (AC), and the tripeptide alpha-amino-adipyl-cysteinyl-valine (ACV) were determined by off-line HPLC. By reducing the pO2 in the production phase from 40 to 5% of its saturation value, the CPC concentration diminished from 7.2 to 1.1 g l-1 and the PEN N concentration increased from 2.57 to 7.65 g l-1. The DAC concentration also dropped from 3.13 to 0.42 g l-1; however, the DAOC concentration was less influenced. The concentrations of AC and ACV were also less affected. The small DOC did not lead to an accumulation of the intermediate AC and ACV during the production phase. With increasing DOC in the range of 5-20%, the maximal specific production rate, the cell mass concentration-based and the substrate-based yield coefficients for CPC increased almost linearly, and fell back for PEN N.(ABSTRACT TRUNCATED AT 250 WORDS)

Cephalosporin production by a highly productive Cephalosporium acremonium strain was carried out and optimized by fed-batch operation in a 40 l stirred tank reactor using a complex medium containing 30-120 g l-1 peanut flour. The concentrations of cephalosporin C (CPC) and its precursors: penicillin N (PEN N), deacetoxy cephalosporin C (DAOC), and deacetyl cephalosporin C (DAC) were monitored with an on-line HPLC. The concentrations of amino acids valine (VAL), cysteine (CYS), alpha-amino adipic acid (alpha-AAA), the dipeptide alpha-amino-adipyl-cysteine (AC), and the tripeptide alpha-amino-adipyl-cysteinyl-valine (ACV), were determined off-line by HPLC. The RNA content and dry weight of the sediment as well as the oxygen transfer rate (OTR) and the CO2 production rate (CPR) were used to calculate the cell mass concentration (X). The influences of peanut flour (PF) and the on-line monitored and controlled medium components: glucose (GLU), phosphate, methionine (MET) as well as the dissolved oxygen (DOC) on the cell growth, the product formation, and the pathway of cephalosporin C biosynthesis were investigated and evaluated. When the glucose fed-batch cycle was optimized and oxygen transfer limitation was avoided (DOC greater than 20% of the saturation value), high process performance (103.5 g l-1 X, 11.84 g l-1 CPC, a maximum CPC productivity of 118 mg l-1 h-1, and the whole concentration of the beta-lactam antibiotics CPC, DAC, DAOC, PEN N 17.34 g l-1) was achieved by using 100 g l-1 PF in the medium with the optimum concentration of phosphate (260-270 mg l-1) and a low glucose concentration (less than 0.5 g l-1). The cultivations with different medium concentrations demonstrated that the product formation was directly proportional to the cell mass concentration. On the average, the cell mass-based yield coefficient of CPC: YCPC/X amounted to 0.115 g CPC per g cell mass.

The influence of stirrer speed in the third preculture on the performance of penicillin V production by Penicillium chrysogenum in complex medium in a 100-l air-lift tower loop reactor was investigated. The process performance in the main culture was improved by increasing the stirrer speed from 500 to 750 rpm: the pellet size was reduced to half, the cell growth was influenced only slightly, but the production phase was extended considerably, and the final penicillin concentration was increased from 5.1 g l-1 to 10.4 g l-1.