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Background and study aims: The long-term comprehensive prognosis of chronic hepatitis C after direct-acting antiviral (DAA) therapy is unclear. This study aimed to investigate the prognosis and incidence of immunological and oncological complications after DAA therapy. Patients and methods: The study included a total of 1461 patients who received DAA therapy in our university hospital and affiliated hospitals between September 3, 2014 and September 30, 2018. Results: The incidence rates of total malignancies in overall or female patients after DAA therapy were significantly greater than expected in the corresponding general population. The same was true for lung malignancies. Predictive risk factors associated with the occurrence and recurrence of hepatic malignancies after DAA therapy in patients with sustained virological response were cirrhosis and insulin use, protein induced by vitamin K absence or antagonist-II level, and albumin-bilirubin score, respectively. Eight (0.5%) patients were diagnosed with autoimmune diseases after starting DAA therapy. Importantly, the attending physician considered a possible causal relationship between DAA therapy and these autoimmune diseases in five cases (four rheumatoid arthritis and one membranoproliferative glomerulonephritis). The 5-year overall survival rate was 91.6%. The most frequent primary cause of death was malignancy in 41 (60.2%) patients, including 25 with hepatic malignancies. Lung and colorectal cancers were the next most common. Conclusions: Given that the incidence of total and lung cancers might increase and DAA-related autoimmune diseases might emerge after DAA therapy, we should be alert for the development of these diseases as well as hepatic malignancies.

In this work, the successful preparation of the multilayer Titanium doped diamond-like carbon/Ti (Ti-DLC/Ti) films deposited on low-carbon steel (CS) using hybrid magnetron sputtering (MS) and plasma-enhanced chemical vapor deposition methods has been reported. The Ti and Ti-DLC films were alternately deposited on the CS substrate of up to 4 stacks with an average deposition rate of 16.4±1.7 nm/min and 15.1±1.5 nm/min, respectively, yielding a total thickness of up to 1703 nm. Raman spectroscopic analysis revealed a gradual increase in the I D/I G ratio with an increase in Ti layer numbers. Both XPS and NEXAFS results indicate an increase in the C-sp 2 content by increasing the number of Ti layer, which may influence on the hardness reduction. The adhesive properties were found to be improved by adding the number of Ti interlayers between the CS substrate. Moreover, the thicker multilayer films exhibit progressive homogeneity resulting in better corrosion resistance.

Nickel oxide (NiO)-decorated titanium dioxide (TiO2) heterojunction photodetectors were prepared by two-step anodization. Surface scattering of NiO particles was successfully controlled by varying second-step anodizing voltage, with substantially less clustering of NiO particles on the TiO2 nanotubes (NTs) observed as the voltage increased. Fabricated photodetectors exhibited higher sensitivity to UV light as NiO surface dispersion increased. Electronic bandgap of TiO2 and that of NiO was determined as ~ 3.35 eV and ~ 3.80 eV, respectively. Introduction of NiO particles on well-ordered TiO2 NTs narrowed the bandgap of TiO2, and the difference between work functions of TiO2 and NiO produced sufficient built-in electric field to separate the electron–hole pairs. This led to an enhanced performance of NiO/TiO2 heterojunction photodetectors, which showed high values of responsivity (86 A/W), external quantum efficiency (292%), and detectivity (2.2 × 1010 Jones) under 365 nm UV light illumination. The valence and conduction band offsets at the interface of the NiO/TiO2 heterojunction were determined as ~ 1.54 eV and ~ 1.99 eV, respectively.

Accurate and simultaneous multiposition near-field measurements are essential to study the time-dependent local dynamics, including heat and carrier transfer. The existing passive long-wavelength infrared (LWIR) scattering-type scanning near-field optical microscopy (s-SNOM) systems with a single probe cannot perform precise near-field measurements of the heat or carrier transporting process at the nanoscale level. Therefore, in this study, we developed a passive LWIR s-SNOM system with two probes. To test the effectiveness of the proposed passive LWIR dual-probe s-SNOM system, each probe was precisely controlled using a shear-force feedback system, and the mechanical interference between the probes was used to monitor the distance between the probes. We achieved simultaneous near-field measurements at two different positions 500 nm apart using the proposed passive LWIR dual-probe s-SNOM system. The simultaneously detected near-field signals from two different points were extracted individually, making this technique an effective nanoscale analysis tool for local carrier dynamics.

To suppress excessive gate voltage swings during switching, a resistance is normally used to limit the charging rate of the gate capacitance (C G ). Modern solutions, such as segmented gate drivers, can be used to dynamically control the gate resistance R G to minimize ringing while maintaining the fast-switching speed of the transistor. The timing or dynamic pattern of the gate resistance is critical in the optimization of the device and circuit performance. Traditionally, this gate drive pattern is obtained via a trial-and-error or iterative procedure. This paper proposes a method to automatically determine the timing intervals by monitoring the gate signal (V GATE ) through slope sensing with analog filter and subsequent mixed-signal processing. The output timing indicator (T SEG ) is then fed back to the segmented gate driver IC to achieve automatic adjustments of the dynamic driving pattern. The proposed system is able to determine the optimum T SEG for dynamic gate driving. For the SiC power MOSFET used in our testing, segmented R G driving between 2.5 and 10 Ω does not hinder the switching speed, while keeping the undershoot of the SiC module to be within 1 V or 5% of the total applied gate voltage.

Light-sensitive capacitance variation of Bi0.95La0.05FeO3 (BLFO) ceramics has been studied under violet to UV irradiation. The reversible capacitance enhancement up to 21% under 405 nm violet laser irradiation has been observed, suggesting a possible degree of freedom to dynamically control this in high dielectric materials for light-sensitive capacitance applications. By using ultraviolet photoemission spectroscopy (UPS), we show here that exposure of BLFO surfaces to UV light induces a counterintuitive shift of the O2p valence state to lower binding energy of up to 243 meV which is a direct signature of negative electronic compressibility (NEC). A decrease of BLFO electrical resistance agrees strongly with the UPS data suggesting the creation of a thin conductive layer on its insulating bulk under light irradiation. By exploiting the quantum capacitance model, we find that the negative quantum capacitance due to this NEC effect plays an important role in this capacitance enhancement

In this work, electronic structure variations of MoS2 under violet laser irradiation and potassium evaporation have been studied by angle-resolved photoemission spectroscopy (ARPES). By exposing violet laser on the fresh MoS2 surface, we found the shift of valence band to the higher binding energy of 140±10 meV. This behavior can be described by the optical excitation where electrons in the valence band are temporary pumped to the conduction band edge. By using potassium evaporation, the shift of valence band of 280±20 meV to higher binding energy as well as the emerging of conduction pockets at K point which are a result of electron donation from alkali metals. Another shift of valence band up to 40±10 meV have been observed after irradiating violet laser on the doped sample. The schematic band diagram which can be described the chemical shifts based on experimental ARPES data has been proposed. By using transport measurement, a variation of MoS2 electrical resistance under light irradiation supports the nonequilibrium electron donation induced by optical excitation.

Organic-inorganic hybrid perovskite could potentially be used to create field-effect transistors (FETs) with high field-effect mobility. However, the energy level mismatch at the deep valence band maximum perovskite-contact junction and morphological defects greatly limit the charge transport in the thin film. In this work, we demonstrated charge injection can be improved by introducing Nafion as a surface modifier on top of the Indium tin oxide. Incorporating poly (9-vinylcarbazole) PVK into a quasi-one-dimensional precursor solution induced preferential vertically orientated nanopillars as revealed by synchrotron-based two-dimensional grazing incident X-ray diffraction. This simultaneously reduced the grain boundaries and improved pin-hole free films. As a result, maximum hole mobility of 0.012 cm2/Vs was achieved with a reduction in the hysteresis. Our work demonstrated the dependence of FETs performance on the injection barrier and perovskite nanopillar microstructure.

Light-sensitive capacitance variation of Bi0.95La0.05FeO3 (BLFO) ceramics has been studied under violet to UV irradiation. The reversible capacitance enhancement up to 21% under 405 nm violet laser irradiation has been observed, suggesting a possible degree of freedom to dynamically control this in high dielectric materials for light-sensitive capacitance applications. By using ultraviolet photoemission spectroscopy (UPS), we show here that exposure of BLFO surfaces to UV light induces a counterintuitive shift of the O2p valence state to lower binding energy of up to 243 meV which is a direct signature of negative electronic compressibility (NEC). A decrease of BLFO electrical resistance agrees strongly with the UPS data suggesting the creation of a thin conductive layer on its insulating bulk under light irradiation. By exploiting the quantum capacitance model, we find that the negative quantum capacitance due to this NEC effect plays an important role in this capacitance enhancement

A Chopper-type Marx modulator is being developed to drive a 10 MW L-band multi-beam klystron for the international linear collider at the High Energy Accelerator Research Organization (KEK). Twenty units are connected in series to provide the klystron with a −120 kV, 140 A, 1.65 ms pulse at a repetition rate of 5 pps. This paper describes the present status of the Chopper-type Marx modulator being developed at KEK.

Toxoplasma is a common parasite worldwide that mainly affects the brain, lungs and eyes. Although toxoplasmic encephalitis is a lethal disease without treatment, past case reports show most patients with systemic lupus erythematosus who developed toxoplasmic encephalitis were misdiagnosed and treated as neuropsychiatric systemic lupus erythematosus, which led to unfavorable outcomes. We herein describe a case of disseminated toxoplasmosis affecting all the above organs with atypical symptoms, which developed with exacerbation of systemic lupus erythematosus. She had initially manifested with retinochoroiditis without vitritis, mild cognitive impairment and an isolated lung mass. These are completely different from the classic symptoms of toxoplasmosis that have been reported in patients with HIV infection and/or those after hematopoietic transplantation. Our case, together with previously reported cases, suggests the manifestation of toxoplasmosis that develops in systemic lupus erythematosus patients can be different from that seen in conventional cases and varies between individual patients. Our case highlights both the difficulty in and the importance of diagnosing toxoplasmosis in patients with systemic lupus erythematosus and provides helpful information to identify this rare, devastating, yet treatable disease.

Japanese cuisine is now popular worldwide, and consumption of raw fish has thus increased at sushi bars and Japanese restaurants outside Japan. Anisakiasis, also known as herring-worm disease, is caused by ingesting larval nematodes in raw seafood and is a common illness in Japan. However, due to the rising popularity of Japanese food, gastroenterologists outside Japan need to be familiar with this disease.We treated 158 patients presenting with acute gastrointestinal manifestations caused by anisakiasis from April 1991 to April 2000. One or more nematodes were removed endoscopically within 48 h of presentation in 44% of these patients, which resulted in prompt resolution of symptoms. Major endoscopic findings were gastric ulcer accompanied by hemorrhage, erosion, redness, and edema of the gastric mucosa in areas penetrated by larvae and other areas.Endoscopy was valuable for the diagnosis and treatment of anisakiasis. We recommend endoscopy in suspected cases of anisakiasis. Moreover, it is desirable to combine complementary tests such as immunological tests/IgE measurement. As the popularity of Japanese cuisine increases, reports of anisakiasis are likely to be more frequent in countries other than Japan.

Interferometric Synthetic Aperture Radar (InSAR) technique is able to detect a slope deformation around landslide (e.g., Singhroy et al., 2004; Une et al., 2008; Riedel and Walther, 2008; Sato et al., 2014). Geospatial Information Authority (GSI) of Japan has been performing the InSAR analysis regularly by using ALOS/PALSAR data and ALOS-2/PALSAR-2 data throughout Japan. There are a lot of small phase change sites except for crustal deformation with earthquake or volcano activity in the InSAR imagery. Most of the phase change sites are located in landslide area. We conducted field survey at the 10 sites of those phase change sites. As a result, we identified deformation of artificial structures or linear depressions caused by mass movement at the 9 sites. This result indicates that InSAR technique can detect on the continual deformation of landslide block for several years. GSI of Japan will continue to perform the InSAR analysis throughout Japan. Therefore, we will be able to observe and monitor precursory slope deformation around landslide areas throughout Japan.

The seizure threshold 2 (SZT2) gene encodes a large, highly conserved protein that is associated with epileptogenesis. In mice, Szt2 is abundantly expressed in the central nervous system. Recently, biallelic SZT2 mutations were found in 7 patients (from 5 families) presenting with epileptic encephalopathy with dysmorphic features and/or non-syndromic intellectual disabilities. In this study, we identified by whole-exome sequencing compound heterozygous SZT2 mutations in 3 patients with early-onset epileptic encephalopathies. Six novel SZT2 mutations were found, including 3 truncating, 1 splice site and 2 missense mutations. The splice-site mutation resulted in skipping of exon 20 and was associated with a premature stop codon. All individuals presented with seizures, severe developmental delay and intellectual disabilities with high variability. Brain MRIs revealed a characteristic thick and short corpus callosum or a persistent cavum septum pellucidum in each of the 2 cases. Interestingly, in the third case, born to consanguineous parents, had unexpected compound heterozygous missense mutations. She showed microcephaly despite the other case and previous ones presenting with macrocephaly, suggesting that SZT2 mutations might affect head size.

Japan Atomic Energy Agency (JAEA) has been conducting manufacturing feasibility trials of the toroidal field coil structures since 2009. Their feasibility was confirmed; however, since the structures were welded by using a one-side welding method, welding deformation was much larger than expected. By using a double-side welding method and optimizing the welding sequence, welding deformation can be minimized. Therefore, JAEA conducted full-scale trial manufacturing of basic segments to optimize the double-side welding sequence. After optimization, welding deformation was reduced. As a result, the double-side welding method will be used to manufacture the toroidal field coil structures as a manufacturer's selection.

ITER toroidal field coil (TFC) structures are large welding structures composed of coil case and support structures made of heavy thick high strength and high toughness stainless steels. Japan Atomic Energy Agency plans to apply narrow gap Tungsten Inert Gas (TIG) welding with FMYJJ1 (0.03C–10Mn–12Cr–14Ni–5Mo–0.13N) which is full austenitic stainless filler material. In order to evaluate effect of base material thickness and combinations of base material on tensile properties, tensile tests were performed at room temperature, 77 K and 4 K by using tensile specimens taken from 200 mm thickness welded joints of two combinations of base materials and 40 mm thickness welded joints of four combinations of base materials. As the results, it was confirmed that there were no large distribution of yield and tensile strength along the thickness of welded joints of 200 mm thickness and yield and tensile strengths of welded joints were decreased with decreasing of C + N contents of base material.

An artificial peroxidase with thermal tolerance and high catalytic activity has been successfully prepared by mutagenesis of an electron transfer protein, cytochrome c552 from Thermus thermophilus. The mutant enzymes were rationally designed based on the general peroxidase mechanism and spectroscopic analyses of an active intermediate formed in the catalytic reaction. Stopped flow UV-vis spectroscopy and EPR spectroscopy with a rapid freezing sample technique revealed that the initial double mutant, V49D/M69A, which was designed to reproduce the peroxidase mechanism, formed an active oxo-ferryl heme intermediate with a protein radical predominantly localized on Tyr45 during the catalytic reaction. The magnetic power saturation measurement obtained from EPR studies showed little interaction between the oxo-ferryl heme and the tyrosyl radical. Kinetics studies indicated that the isolated oxo-ferryl heme component in the active intermediate was a possible cause of heme degradation during the reaction with H2O2. Strong interaction between the oxo-ferryl heme and the radical was achieved by replacing Tyr45 with tryptophan (resulting in the Y45W/V49D/M69A mutant), which was similar to a tryptophanyl radical found in active intermediates of some catalase-peroxidases. Compared to the protein radical intermediates of V49D/M69A mutant, those of the Y45W/V49D/M69A mutant showed higher reactivity to an organic substrate than to H2O2. The Y45W/V49D/M69A mutant exhibited improved peroxidase activity and thermal tolerance.

An artificial peroxidase with thermal tolerance and high catalytic activity has been successfully prepared by mutagenesis of an electron transfer protein, cytochrome c552 from Thermus thermophilus. The mutant enzymes were rationally designed based on the general peroxidase mechanism and spectroscopic analyses of an active intermediate formed in the catalytic reaction. Stopped flow UV-vis spectroscopy and EPR spectroscopy with a rapid freezing sample technique revealed that the initial double mutant, V49D/M69A, which was designed to reproduce the peroxidase mechanism, formed an active oxo-ferryl heme intermediate with a protein radical predominantly localized on Tyr45 during the catalytic reaction. The magnetic power saturation measurement obtained from EPR studies showed little interaction between the oxo-ferryl heme and the tyrosyl radical. Kinetics studies indicated that the isolated oxo-ferryl heme component in the active intermediate was a possible cause of heme degradation during the reaction with H2O2. Strong interaction between the oxo-ferryl heme and the radical was achieved by replacing Tyr45 with tryptophan (resulting in the Y45W/V49D/M69A mutant), which was similar to a tryptophanyl radical found in active intermediates of some catalase-peroxidases. Compared to the protein radical intermediates of V49D/M69A mutant, those of the Y45W/V49D/M69A mutant showed higher reactivity to an organic substrate than to H2O2. The Y45W/V49D/M69A mutant exhibited improved peroxidase activity and thermal tolerance.

Japan Atomic Energy Agency (JAEA), acting as the Japan Domestic Agency (JADA) in the ITER project is responsible for the procurement of 9 Toroidal Field (TF) coil winding packs (WPs), structures for 19 TF coils (including one spare), and assembly of the WPs and the coil structures for 9 TF coils [1] . The TF Coil structures which support large electromagnetic force generated in TF coils under the cryogenic temperature (about 4 K), are very large welded structures composed of a coil case and structural attachments made of high strength and high toughness stainless steel. JAEA has been performing welding trials for heavy thickness materials since 2008 and is planning fabrication of full-scale mock-ups of main sub-components (1 set for the inboard side and 1 set for the outboard side) in 2011 in order to investigate the technical issues for manufacturing the TF coil structures. This paper presents the results of welding trials and the status of full scale mock-ups fabrication to confirm the validity of welding technology and manufacturing design before fabricating the actual products.

The Japan Atomic Energy Agency (JAEA) is responsible for the procurement of 9 TF coils as the Japanese Domestic Agency in the ITER project. Small- and full-scale trials are being performed to demonstrate and optimize fabrication procedures before starting production of the TF coils. JAEA is carrying out the conductor winding and insulation/impregnation trials in advance of the other trials because they represent key processes in TF coil manufacture. Mechanical tests of the conductors are performed to ascertain their bending behavior during winding. The commissioning of tooling for the one-third scale winding already is complete. The winding test was conducted using a specially developed winding head which resulted, based on mechanical test results, in achieving a curvature of the bent conductor in line with expectations. Impregnation trials using the acrylic and metallic model were performed to demonstrate the impregnation procedure and the applicability of bonded glass–polyimide tape, which is expected to facilitate the winding of the insulation tape around the conductor. Results demonstrate the suitability of the bonded glass–polyimide tape for the impregnation procedure.

The Japan Atomic Energy Agency (JAEA) has the responsibility to procure 25% of the ITER Toroidal Field Coil conductors as the Japanese Domestic Agency (JADA) in the ITER project. The TF conductor is a circular shaped, cable-in-conduit conductor, composed of a cable and a stainless steel conduit (jacket). The outer diameter and maximum length of the TF conductor are 43.7 mm and 760 m, respectively. JAEA started to produce strand, cables and jacket sections and to construct a conductor manufacturing (jacketing) facility in 2008. Following preparation in December 2009 of the jacketing facility, the dummy cable, the jacket sections and fabrication procedures, such as welding, cable insertion, compaction and spooling, JAEA manufactured a 760 m long Cu dummy conductor for process qualification. Into the 760 m long Cu dummy conductor jacketing, JAEA successfully inserted the cable with a maximum force of 32 kN. The outer diameter of the cross section of the spooled conductor was 43.7 ± 0.15 mm, which complies with the ITER target requirement of 43.7 ± 0.3 mm. Following qualification of all manufacturing processes, JAEA has started to fabricate superconducting conductors for the TF coils.

Nitrogen oxides (NOx) are one of the air pollutants that cause acid rain. Although utilization of catalysts is a typical established method of treatment to remove NOx, the catalyst is expensive so that the total cost of treatment is high. The efficient treatments using pulsed power, which utilize the pulse streamer discharges, have been studied. We have brought the nanosecond pulsed power to the NOx treatment. More efficient treatment is expected with the high electric fields with a nanosecond pulse width. In using the nanosecond pulsed power, the issue of design and modification of reactors configuration becomes important. Coaxial reactors consisting of wire-cylinder electrodes are adopted here and three types of electrical connecting methods between a generator and reactor chambers and gas tubing methods were investigated. The deposited energy density of 150 J/L yielded approximately 100% NO removal ratio for initial NO gas of 100 ppm. The three types of electrical connections were parallel, straight and serial. The parallel and straight connections yielded a higher removal ratio and efficiency in this experiment. Distribution of voltage in the reactors affects the removal ratio and efficiency since the production and development of streamer discharges depends of the amplitude of voltage. While propagating voltage pulses will decay in the reactors, reflections of voltage pulse at the open end of the reactors multiply the voltage distribution. Although impedance matching between the pulsed power generator and the reactors should be important, a multiplication of the transparent voltage pulse into the reactors by mismatching may improve the treatment.

The critical current of a cable-in-conduit conductor (CICC) for an ITER TF coil was measured using the SULTAN test facility. It was found that a non-uniform current distribution was established due to a non-uniform joint resistance. To evaluate the critical current performance accurately, we used a solder-filled joint. To study the effect of this solder-filled joint on the current distribution, we used a lumped circuit model and a distributed circuit model for the conductor and the joint, respectively, and combined the two to develop a new analysis model. This enabled us to solve the distributed circuit equation using only a few iterations, resulting in considerable reduction of the calculation time. Simulation results showed that, although the current distribution was non-uniform due to the ramping current, it improved at the current sharing temperature. This indicated that the solder-filled joint effectively improved the current distribution.

The superconducting properties of Nb3Sn strands are very sensitive to strain. Measuring internal strain of Nb3Sn in Cable-In-Conduit Conductors (CICC) is important for evaluating the superconducting performance of CICC. Internal strain can be determined by neutron diffraction measurement using Takumi of J-PARC. Neutron diffraction measurement becomes a strong tool for evaluating directly the internal strain of Nb3Sn in CICC.

The Japan Atomic Energy Agency (JAEA) developed ITER TF Nb3Sn conductors that fulfill ITER requirements and has commenced fabricating the conductors to be used in the ITER TF coils. As a qualification of conductor fabrication, two full-size conductor samples, named as JATF4, were prepared and tested by the SULTAN facility at CRPP in Switzerland. Temperature sensors and voltage taps were attached on the three meter-long conductor samples to measure the current sharing temperature (Tcs). Measurements were performed at the beginning of the testing campaign, during cyclic test, and at the end of the campaign following a warm up and cool down. The Tcs values electrically assessed by the agreed procedure at outer magnetic fields of 10.78 T initially were 6.5 K and 6.2 K, and then 6.1 K and 6.0 K at the end of the campaign for each conductor, respectively. These results demonstrate that the conductors have a sufficient Tcs margin to satisfy the ITER TF conductor criterion of 5.7 K, and conductor fabrication is qualified. Details of the test results are presented and discussed.

To detect the invasiveness of exotic plants and their effects on native species, the distribution patterns of exotics and natives were examined in the metropolitan city of Sapporo (1,121 km2), northern Japan, by flora lists for 53 districts. The urbanization history has two phases, after the 1868 Meiji Restoration, and after the 1945 World War II End. We analyzed the plant distribution patterns digitized by flora list recorded 45 years after the World War II. The distribution was compared with life forms, immigration ages and environmental factors by numerical analyses. The findings are: (1) Exotics immigrated to the whole areas for short term, and the distribution patterns were determined more by social and economic factors, in particular population density, than by physical factors, such as elevation and geology. (2) Life form is related to the distribution of exotics; viz. annual exotics establish intensively in urbanized areas but do not exclude natives, while perennial exotics, in particular, immigrated before World War II are widespread. To restrict exotics, therefore, prompt treatment to new perennial exotics before becoming biologically invasive plants is important for conserving natural flora. (3) However, the number of exotics increased with the number of natives, showing that the exotics have not significantly deteriorated native flora in the present. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

RESUME Notre pays, qui possede d’importantes ressources d’eaux souterraines et superficielles, a su conduire au service de la nation une politique equilibree dans le domaine des eaux de consommation humaine. Il s’est appuye pour cela sur les recommandations edictees par l’Organisation Mondiale de la Sante, les Directives Europeennes les plus recentes, les Lois et les Codes necessaires ainsi que, plus recemment, sur les lois issues du « Grenelle de l’Environnement » et des Plans-Nationaux-Sante-Environnement 1 et 2. Il s’est dote egalement d’instances de gouvernance appropriees. Ce rapport confirme tout d’abord la necessite d’ameliorer et de preserver la qualite des ressources en eau en vue du developpement durable et de poursuivre les efforts entrepris pour ameliorer a la fois le traitement des eaux usees et la qualite de l’eau de consommation, grâce a l’evolution constante des recherches et des innovations techniques dans ces domaines ainsi que le developpement de l’assurance qualite. Les differentes caracteristiques des eaux de consommation humaine : eaux minerales naturelles, eaux de source conditionnees et eaux de distribution publique sont precisees. Ces dernieres font l’objet d’explications sur leur gestion, leur origine, leur transport, leurs modalites de production et les controles de qualite auxquels elles sont assujetties. La qualite de l’eau de consommation humaine, qui est definie sur la base de normes considerees comme des limites de qualite pour certaines et des references de qualite pour d’autres, fait l’objet de precisions qui ont ete associees a d’importants problemes de sante publique. Les recherches dans ce domaine sont essentielles. La communication sur l’eau doit etre etablie en toute transparence. Le prix de l’eau de distribution publique merite une explication simple necessaire a une bonne communication. Ce rapport evoque egalement dans son dernier chapitre les problemes de l’eau au niveau mondial en insistant sur les difficultes de nombreux pays du monde tropical et intertropical, dans ce domaine essentiel pour l’equilibre du monde

Aims: To identify genes cluster for thermophilin 1277 produced by Streptococcus thermophilus SBT1277. Methods and Results: To identify genes for thermophilin 1277 production, the chromosomal DNA region surrounding the structural gene, tepA, was sequenced using a primer-walking method. The thermophilin 1277 biosynthesis gene locus (tep )i s a9 AE9-kb region, which consists of at least ten open reading frames (ORFs) in the following order: tepAMTFEGKRI and ORF4. Homology analysis showed high similarity to genes involved in bovicin HJ50 production by Streptococcus bovis HJ50. tepI encodes a novel, small, positively charged hydrophobic peptide of 52 amino acids, which contains a putative transmembrane segment. By heterologous expression in Lactococcus lactis ssp. cremoris MG1363, the TepI-expressing strain exhibited at least 1AE3 times higher resis