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The capacity of marine sponges to cope with environmental changes is often attributed to the specific composition of their bacterial communities. In this study, we assessed the bacterial microbiome of two dominant sponges, Rhabdastrella globostellata (Rg) and Hyrtios erectus (He), living in the Bouraké lagoon (New Caledonia), where abiotic conditions daily fluctuate according to the tide. Sponge specimens, sediment and seawater samples were collected at 2–3 m depth. The bacterial communities were assessed using 16S rRNA metabarcoding, and variations between the two sponges were compared using PCA biplots. Chloroflexi was the dominant phyla in both He and Rg with an average relative abundance of 41.2% and 53.2%, respectively, while it was absent in sediment and seawater. Among the phylum Chloroflexi, SAR202 clade was dominant in both sponges, reaching an average relative abundance of 53.2% (He) and 78.7% (Rg). Principal component analysis (PCA) was used to identify the main variables driving the bacterial community structure in both sponges. The results indicated that the bacterial community structure in both sponges was strongly associated with Chloroflexi (70.9% of the phyla variance) and SAR202 clade (86.6% of the clade variance). The high relative abundance of the phylum Chloroflexi and the SAR202 clade observed in this study is the highest reported so far in the literature in marine sponges. Such a high relative abundance of these bacteria could suggest their involvement in the well-being of sponges in the extreme environmental conditions of Bouraké.

During the last decade, the world faced record-breaking giant fires as observed in Australia and California, a trend that is expected to increase in the forthcoming years due to climate change (Palinkas, 2020; Sharples et al., 2016; van Oldenborgh et al., 2021). In addition to their large ecological impacts, wildfires are more and more regarded for their potential threat to human health through air pollution (Xu et al., 2020). However, water pollution resulting from wildfires represents an underestimated pathway for wildfires-induced health risk (Abraham et al., 2017). This latter impact is related to the heat generated by wildfires that can propagate towards several centimeters in the soil and transform/destroy soil components. In addition to weakening soil physical stability, such transformation/destruction can change the speciation of potentially toxic elements (PTEs) that are associated with these soil components, leading to enhanced mobility towards waterways (Abraham et al., 2017; Terzano et al., 2021). One notable PTE is chromium, which is naturally present in soils mostly as trivalent Cr(III), but can represent an environmental and health issue when occurring as hexavalent Cr(VI). Recent studies reported Cr(III) oxidation to Cr(VI) upon laboratory-heating of Cr(III)-doped Fe-oxyhydroxides (Burton et al., 2019a; 2019b). Besides, Cr(III) oxidation to Cr(VI) upon controlled heating was also demonstrated for different types of soils (Burton et al., 2019b; Rascio et al., 2022; Thery et al., 2023). All these considerations suggest a significant effect of wildfires on Cr(III) oxidation to Cr(VI) in soils, with a possible influence on Cr mobility that could further impact freshwater quality. This risk of freshwater Cr(VI) pollution is expected to particularly concern ultramafic catchments because of the related occurrence of Cr-rich soils.We have tried to address this question by performing laboratory-heating of several soils types (Ferralsols, Cambisols and Vertisols) developed on various geological settings (ultramafic, mafic and volcano-sedimentary) in New Caledonia, a French overseas territory which is a good representative of wildfires-threatened tropical ultramafic catchments (Toussaint, 2020). The results obtained revealed a significant influence of soil heating on Cr(III) oxidation to Cr(VI), followed by an enhanced Cr(VI) mobility, in all soil types. However, the magnitude of Cr(III) to Cr(VI) oxidation and Cr mobility depended on the actual nature of the soil, Ferralsols showing the highest Cr(VI) release compared to Cambisols and Vertisols. These differences were further interpreted on the basis of the changes in Cr speciation (including redox) induced by laboratory-heating of the investigated soils, as revealed by synchrotron-based X-ray absorption spectroscopy analyses. Finally, a simple risk assessment relying on the hypothesized concentration of suspended particulate matter (SPM) issued from burned soils in the related waterways allowed to emphasize a risk of wildfires-induced freshwater Cr(VI) pollution for ultramafic catchments composed of Ferralsols (Thery et al., 2023). Beyond the single case of New Caledonia, the results of this study point to the need to foster collaborative studies in order to further evaluate this risk of wildfires-induced freshwater Cr(VI) pollution at tropical ultramafic catchments on a global scale.

The present study focused on the characterization of 10

Nickel (Ni)-tolerant ectomycorrhizal Pisolithus albus was isolated from extreme ultramafic soils that are naturally rich in heavy metals. This study aimed to identify the specific molecular mechanisms associated with the response of P. albus to nickel. In presence of high concentration of nickel, P. albus Ni-tolerant isolate showed a low basal accumulation of nickel in its fungal tissues and was able to perform a metal efflux mechanism. Three genes putatively involved in metal efflux were identified from the P. albus transcriptome, and their overexpression was confirmed in the mycelium that was cultivated in vitro in the presence of nickel and in fungal tissues that were sampled in situ. Cloning these genes in yeast provided significant advantages in terms of nickel tolerance (+ 31% Ni EC50) and growth (+ 83% u) compared with controls. Furthermore, nickel efflux was also detected in the transformed yeast cells. Protein sequence analysis indicated that the genes encoded a P-type-ATPase, an ABC transporter and a major facilitator superfamily permease (MFS). This study sheds light on a global mechanism of metal efflux by P. albus cells that supports nickel tolerance. These specific responses to nickel might contribute to the fungal adaptation in ultramafic soil. (Resume d'auteur)

International audience; Ectomycorrhizal fungi (ECM) isolates of Pisolithus albus (Cooke and Massee) from nickel-rich ultramafic topsoils in New Caledonia were inoculated onto Acacia spirorbis Labill. (an endemic Fabaceae) and Eucalyptus globulus Labill. (used as a Myrtaceae plant host model). The aim of the study was to analyze the growth of symbiotic ECM plants growing on the ultramafic substrate that is characterized by high and toxic metal concentrations i.e. Co, Cr, Fe, Mn and Ni, deficient concentrations of plant essential nutrients such as N, P, K, and that presents an unbalanced Ca/Mg ratio (1/19). ECM inoculation was successful with a plant level of root mycorrhization up to 6.7%. ECM symbiosis enhanced plant growth as indicated by significant increases in shoot and root biomass. Presence of ECM enhanced uptake of major elements that are deficient in ultramafic substrates; in particular P, K and Ca. On the contrary, the ECM symbioses strongly reduced transfer to plants of element in excess in soils; in particular all metals. ECM-inoculated plants released metal complexing molecules as free thiols and oxalic acid mostly at lower concentrations than in controls. Data showed that ECM symbiosis helped plant growth by supplying uptake of deficient elements while acting as a protective barrier to toxic metals, in particular for plants growing on ultramafic substrate with extreme soil conditions. Isolation of indigenous and stress-adapted beneficial ECM fungi could serve as a potential tool for inoculation of ECM endemic plants for the successful restoration of ultramafic ecosystems degraded by mining activities.

The design, simulation and implementation of a dedicated Class-E driver for inductive power transfer is presented. Whereas focus is placed on wireless endoscopy, other upper body monitoring applications can be powered simultaneously. The driver is developed to generate a sinusoidal current signal through a coil, for the generation of an alternating magnetic field at 1 MHz with a field intensity of about 300 μT. The volume within the coil, implemented in a Helmholtz configuration, wherein this magnetic field is guaranteed, allows to cover a volume up to ∼0.2 m 3 . This is an improvement by a factor of 20 compared to previous work [1] and sufficiently large to cover the full upper body of patients. The magnetic field thereby generated, is adequate to provide up to 300 mW of power to previously developed capsules, in all possible orientations. Patient safety and solutions to reduce parasitic influences are addressed briefly.

The design, fabrication and integration of capacitive void fraction sensors for microfluidic applications in silicon microchannels of 100 μm wide and 500 μm deep are described. Microfabrication steps such as electrode deposition, glass dicing and drilling and the anodic bonding process are elucidated. A read-out circuit was designed to convert capacitive input signals into a large-swing analog output signal. The signal processing algorithm is discussed. Measurements showing the variation of the output signal in function of the gas content in the air/water-mixture that was pumped through the microchannels are presented. ispartof: pages:643-646 ispartof: Procedia Engineering vol:47 pages:643-646 ispartof: Eurosensors location:Kraków, Poland date:9 Sep - 12 Sep 2012 status: published

International audience; This study focuses on the chemotaxis, colonization and rice growth promoting ability of indole acetic acid (IAA) and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase-producing rhizobacteria Rhizobium leguminosarum bv. trifolii SN10, previously isolated from root nodules of Trifolium alexandrium L. We show here that R. leguminosarum bv. trifolii SN10 promote the growth of four different rice varieties grown in India in terms of biomass, root branching and N content. In addition, using scanning electron microscopy and viable cell counts, we provide evidence that the bacteria successfully colonize the root surface of the rice variety which showed maximum growth promotion upon inoculation. Not only this, R. leguminosarum bv. trifolii SN10 exhibit a strong chemotaxis response towards the rice seed and root exudates despite the presence of a bacteriostatic phenolic compound, 7-hydroxycoumarin (umbelliferone). Further, R. leguminosarum bv. trifolii SN10 secretion of phytohormones such as IAA and ACC deaminase suggest the potential of the plant growth promoting rhizobacteria to be used as biofertilizer to enhance rice crop production in the subcontinent.

This paper introduces the BladderPill: an in vivo sensor system which is inserted into the bladder cavity through minimal invasive cystoscopy. It allows the autonomous monitoring and logging of the internal bladder pressure. Prototype circuits have been realized and tested in various layouts, to gradually approach the final pill-shaped form, measuring 40 mm in length and 5 mm in diameter. Constructed out of off-the-shelf components and embedded into silicone as a protective encapsulation, a low-cost flexible implant is created. The circuits fit on a double-sided flex measuring 4.2 mm × 18 mm and consume on average 350 μ A. Operation for over 24 h is thus assured on a 13 mAh lithium cell with a diameter of 3 mm.

A system is presented that monitors two of the most vital physiological parameters integrated in a wearable textile garment. Emphasis is put on the selection of sensing systems that are mechanically robust to suit the use in clothing. One application is with newborns suffering from an elevated risk for Sudden Infant Death Syndrome (SIDS). Heart and breathing rate are measured by sensing systems implemented on flexible substrates, integrated onto textile. Breathing rate is assessed by extracting accelerometer signals, which can also be used to detect the posture of the baby. The accelerometers have an accuracy of 1 mg and consume less than 2 mA, interface circuit included. Heart rate is assessed through ECG measurement with dry electrodes and a three-stage differential amplifier with a CMRR of 106 dB at 50 Hz. The system operates on a flexible 3.7 V battery and sends its acquired data wirelessly (at 2.4 GHz with a bandwidth of 770 Hz) to a computer, which processes and visualises the two parameters. Processing involves filtering and peak detection algorithms to extract the breathing and heart rate in Matlab. Because the presented work focuses on the two most important vital signs, the system already proves more robust than common home monitoring SIDS applications, typically focusing on a single parameter. Moreover, the use of accelerometers enables a safe and hermetic packaging technique that excludes unwanted interference.

This paper presents the design and implementation of an advanced system on flexible and stretchable technology. The technology platform consists of a matrix of flexible non-stretchable functional islands linked together by a net of elastic interconnections. Several technologies have been developed and tested in the design of simplified demonstrators before studying the design of an advanced system. The target system is a wireless battery charger which supplies power and supports bidirectional data transfer during recharge. The system is intended to serve as a general purpose platform for biomedical parameter monitoring and the design is focused on the embedding in clothes. ispartof: Sensors and Actuators A, Physical vol:156 issue:1 pages:79-87 ispartof: location:GERMANY, Dresden status: published

A system was designed on flexible substrates to measure two of the most important physiological parameters in human life: breathing rhythm and ECG. A promising feature is the adoption of accelerometers to quantify the breathing cycle. The realised designs were placed on a T-shirt and tested on adults, keeping in mind the parameter variability when used with infants. Data is sent to a computer wirelessly for analysis. Future work includes the integration of the system with an earlier developed wireless battery charger, to ultimately create a textile integrated, fully silicone embedded, infant monitoring system for all vital functions.

A miniature battery powered internal bladder pressure monitoring system is presented, implantable through minimal invasive catheterisation. Prototype circuitry and battery fit into a flexible cylindrical pill measuring o 5 mm x 40 mm. The device is intended for off-line monitoring of behaviour and evolution of bladder pressure under normal life circumstances. No external devices are mandatory during examination, ensuring maximal ‘unawareness’ of the system for the patient. Power is distributed from a pin-type o 3 mm lithium cell. The sensor interface was calibrated in a dedicated test-chamber. Finally the circuitry was assembled and successfully tested on two Kapton foils measuring 4.2 x 18 mm2.

Nickel (Ni)-tolerant ectomycorrhizal Pisolithus albus was isolated from extreme ultramafic soils that are naturally rich in heavy metals. This study aimed to identify the specific molecular mechanisms associated with the response of P. albus to nickel. In presence of high concentration of nickel, P. albus Ni-tolerant isolate showed a low basal accumulation of nickel in its fungal tissues and was able to perform a metal efflux mechanism. Three genes putatively involved in metal efflux were identified from the P. albus transcriptome, and their overexpression was confirmed in the mycelium that was cultivated in vitro in the presence of nickel and in fungal tissues that were sampled in situ. Cloning these genes in yeast provided significant advantages in terms of nickel tolerance (+ 31% Ni EC50) and growth (+ 83% μ) compared with controls. Furthermore, nickel efflux was also detected in the transformed yeast cells. Protein sequence analysis indicated that the genes encoded a P-type-ATPase, an ABC transporter and a major facilitator superfamily permease (MFS). This study sheds light on a global mechanism of metal efflux by P. albus cells that supports nickel tolerance. These specific responses to nickel might contribute to the fungal adaptation in ultramafic soil.

Eight Frankia-Gymnostoma nitrogen-fixing symbioses endemic to New Caledonia were studied using a range of techniques including molecular typing of Frankia , infectivity/effectivity and host spectrum of the isolates. The study was conducted on 128 Frankia isolates from the eight Gymnostoma species. The RFLP analysis of the rRNA 16S-23S ITS allowed us to cluster the strains in four groups. Symbiotic characterization of the four groups failed to reveal any host specificity both in term of infectivity or effectivity. The characteristics of the strains were those of Eleagnaceae -infective Frankia strains. Co-inoculation of two Gymnostoma species with mixtures of strains evidenced 11 % of mixed RFLP profiles. In such controlled conditions, this was interpreted as co-infections. This work evidenced original features of these Gymnostoma isolates: (i) they were closer to Eleagnaceae -infective Frankia than Casuarina -infective Frankia ; (ii) closer to atypical Frankia from Casuarina ; (iii) poorly host-specific; and (iv) they had a tendency of co-infection. They could represent a primitive group of Frankia able to survive in a wide range of habitats.

The fungus Pisolithus albus forms ectomycorrhizal (ECM) associations with plants growing on extreme ultramafic soils, which are naturally rich in heavy metals such as nickel. Both nickel-tolerant and nickel-sensitive isolates of P. albus are found in ultramafic soils in New Caledonia, a biodiversity hotspot in the Southwest Pacific. The aim of this work was to monitor the expression of genes involved in the specific molecular response to nickel in a nickel-tolerant P. albus isolate. We used pyrosequencing and quantitative polymerase chain reaction (qPCR) approaches to investigate and compare the transcriptomes of the nickel-tolerant isolate MD06-337 in the presence and absence of nickel. A total of 1,071,375 sequencing reads were assembled to infer expression patterns of 19,518 putative genes. Comparison of expression levels revealed that 30% of the identified genes were modulated by nickel treatment. The genes, for which expression was induced most markedly by nickel, encoded products that were putatively involved in a variety of biological functions, such as the modification of cellular components (53%), regulation of biological processes (27%) and molecular functions (20%). The 10 genes that pyrosequencing analysis indicated were induced the most by nickel were characterized further by qPCR analysis of both nickel-tolerant and nickel-sensitive P. albus isolates. Five of these genes were expressed exclusively in nickel-tolerant isolates as well as in ECM samples in situ, which identified them as potential biomarkers for nickel tolerance in this species. These results clearly suggest a positive transcriptomic response of the fungus to nickel-rich environments. The presence of both nickel-tolerant and nickel-sensitive fungal phenotypes in ultramafic soils might reflect environment-dependent phenotypic responses to variations in the effective concentrations of nickel in heterogeneous ultramafic habitats.

International audience; Crotalaria are plants of the Fabaceae family whose nodulation characteristics have been little explored despite therecent discovery of their unexpected ability to be efficiently nodulated in symbiosis with bacteria of the genusMethylobacterium. It has been shown that methylotrophy plays a key role in this unusual symbiotic system, as it isexpressed within the nodule and as non-methylotroph mutants had a depleting effect on plant growth response.Within the nodule, Methylobacterium is thus able to obtain carbon both from host plant photosynthesis and frommethylotrophy. In this context, the aim of the present study was to show the histological and cytological impacts ofboth symbiotic and methylotrophic metabolism within Crotalaria podocarpa nodules. It was established that ifCrotalaria nodules are multilobed, each lobe has the morphology of indeterminate nodules but with a differentanatomy; that is, without root hair infection or infection threads. In the fixation zone, bacteroids display a sphericalshape and there is no uninfected cell. Crotalaria nodulation by Methylobacterium displayed some very unusualcharacteristics such as starch storage within bacteroid-filled cells of the fixation zone and also the complete lysis ofapical nodular tissues (where bacteria have a free-living shape and express methylotrophy). This lysis could possiblyreflect the bacterial degradation of plant wall pectins through bacterial pectin methyl esterases, thus producingmethanol as a substrate, allowing bacterial multiplication before release from the nodule.

International audience; In New Caledonia, a hot spot of biodiversity, plants from the Cyperaceae family are mostly endemic and considered pioneers of the nickel-rich natural serpentine ecosystem. The aim of the study was to highlight the mycorrhizal status of these Cyperaceae and to bring new insights into the role of this symbiosis in plant tolerance to ultramafic soils. Nine Cyperaceae species were studied and presented evidence of root colonization by arbuscular mycorrhizas (AMs), with frequencies ranging from 8% to 57%. The highest level of AM colonization was observed in plants from the endemic dominant genus Costularia. Molecular evidence demonstrated the presence of Glomus species inside the roots. In a controlled greenhouse assay, AM inoculation of Costularia comosa grown under ultramafic conditions significantly enhanced plant growth, with an increase in biomass by up to 2.4-fold for shoots and 1.2-fold for roots, and also reduced nickel content in roots by 2.5-fold, as compared with the controls. All these data support our hypotheses (i) that a relationship exists between the mycorrhizal status of Cyperaceae and their habitat, and (ii) that AM have a positive role in plant tolerance to ultramafic soils (mineral nutrition and metal tolerance), suggesting the use of these pioneer plants with AM management as potential tools for nickel mine site rehabilitation in New Caledonia.; En Nouvelle-Calédonie, un point chaud de la biodiversité, les plantes appartenant à la famille des Cypéracées sont principalement endémiques et sont considérées comme pionnières de l’écosystème naturel de la serpentine riche en nickel. Cette étude visait à éclaircir le statut mycorhizien de ces Cypéracées et d’apporter un nouvel aperçu de rôle de cette symbiose dans la tolérance des végétaux aux sols ultrabasiques. Neuf espèces de Cypéracées ont été étudiées et la colonisation des racines par des mycorhizes arbusculaires (MA) a été mise en évidence avec des fréquences variant de 8 % à 57 %. Le niveau de MA le plus élevé a été noté chez les plantes du genre endémique dominant Costularia. Les données moléculaires ont démontré la présence de Glomus sp. à l’intérieur des racines. Lors d’un essai en serre contrôlée, l’inoculation de MA chez Costularia comosa cultivée en conditions ultrabasiques a significativement accru la croissance des plants, avec une augmentation de la biomasse des pousses de 2,4 fois et des racines de 1,2 fois, réduisant aussi le contenu en nickel des racines de 2,5 fois, tout cela par rapport au contrôle. Toutes ces données plaident en faveur de l’hypothèse (i) d’une relation entre le statut en mycorhize des Cypéracées et leur habitat, et (ii) du rôle positif des MA dans la tolérance aux sols ultrabasiques (nutrition minérale et tolérance aux métaux), suggérant que ces plantes pionnières parallèlement à la gestion des MA puissent constituer des outils potentiels de réhabilitation des sites miniers de nickel en Nouvelle-Calédonie.

International audience; Ectomycorrhizal (ECM) Pisolithus albus (Cooke & Massee), belonging to the ultramafic ecotype isolated in nickel-rich serpentine soils from New Caledonia (a tropical hotspot of biodiversity) and showing in vitro adaptive nickel tolerance, were inoculated to Eucalyptus globulus Labill used as a Myrtaceae plant-host model to study ectomycorrhizal symbiosis. Plants were then exposed to a nickel (Ni) dose-response experiment with increased Ni treatments up to 60 mg kg (- 1) soil as extractable Ni content in serpentine soils. Results showed that plants inoculated with ultramafic ECM P. albus were able to tolerate high and toxic concentrations of Ni (up to 60 mu g g (- 1)) while uninoculated controls were not. At the highest Ni concentration tested, root growth was more than 20-fold higher and shoot growth more than 30-fold higher in ECM plants compared with control plants. The improved growth in ECM plants was associated with a 2.4-fold reduction in root Ni concentration but a massive 60-fold reduction in transfer of Ni from root to shoots. In vitro, P. albus strains could withstand high Ni concentrations but accumulated very little Ni in its tissue. The lower Ni uptake by mycorrhizal plants could not be explained by increased release of metal-complexing chelates since these were 5- to 12-fold lower in mycorrhizal plants at high Ni concentrations. It is proposed that the fungal sheath covering the plant roots acts as an effective barrier to limit transfer of Ni from soil into the root tissue. The degree of tolerance conferred by the ultramafic P. albus isolates to growth of the host tree species is considerably greater than previously reported for other ECM. The primary mechanisms underlying this improved growth were identified as reduced Ni uptake into the roots and markedly reduced transfer from root to shoot in mycorrhizal plants. The fact that these positive responses were observed at Ni concentrations commonly observed in serpentinic soils suggests that ultramafic ecotypes of P. albus could play an important role in the adaptation of tree species to soils containing high concentrations of heavy metals and aid in strategies for ecological restoration.

Monitoring the breathing rhythm of infants during sleep can be life saving. But today, most monitoring systems lack patient comfort. In this paper an innovative biomedical monitoring system with textile integrated sensors is developed and tested. Monitoring breathing activity is used as a case study, yet, the platform is extendable by an architecture that can contain up to twenty modular sensor channels, divided in several sensor islands. It is therefore useful for all kinds of (biomedical) applications. Flexible carriers for the electronic circuit lead to better textile integration and more wearing comfort. Quantification of breathing rhythm and volume is performed by accelerometers. These breathing signals are calculated on the basis of the technique that the angle of the gravitation vector in the coordinate systems of the accelerometers changes, because of movement of the abdomen. Differential use of two accelerometers makes this measurement insensitive for movement and posture. The comparison of these signals with a spirometer yields promising results.

Bladder pressure monitoring devices have been a topic of great interest for the past two decades. Three devices developed at ESAT-MICAS in this time are reviewed, showing the evolution of these devices. Two of these devices are diagnostic tools small enough to be inserted into the bladder cavity through minimal invasive cystoscopy. The third device is a long term bladder pressure monitoring implant that, if used to drive an artificial sphincter muscle, forms a urological pacemaker that could diminish or rule out urinary incontinence. After a summary of the three devices, recent results are presented from one of the diagnostic tools.

Contact: philippe.jourand@ird.fr; International audience; Isolates of ectomycorrhizal Pisolithus albus were sampled from both ultramafic and volcano-sedimentary soils in New Caledonia, a tropical hotspot of biodiversity, to investigate the relationships between genetic diversity and edaphic constraint through tolerance to nickel (Ni). Carpophore description, spore morphology and phylogenetic analysis based on internal transcribed spacer (ITS) rDNA sequences confirmed that all isolates belong to P. albus and are closely related to other Australasian specimens. Using molecular tools, ITS-restriction fragment length polymorphism and amplified fragment length polymorphism markers, we showed the existence of two distinct genetic clusters within P. albus: ultramafic and volcano-sedimentary. Mycelia response to Ni toxicity supports such a population structure. Pisolithus albus from ultramafic soils included isolates with a high diversity of in vitro Ni tolerance, with both Ni-tolerant isolates (average Ni EC(50) at 575 mu M) and Ni-sensitive isolates (average Ni EC(50) at 37 mu M). In contrast, all isolates from volcano-sedimentary soils were found to be Ni sensitive (average Ni EC(50) at 32 mu M). We highlight that (1) P. albus population from ultramafic soils of New Caledonia are genetically structured in ecotype, and that (2) Ni tolerance among ultramafic isolates suggests an adaptive physiological response to Ni toxicity.

This paper presents the design, implementation and measurements of a spirometer based on differential pressure sensing. A system which fulfills the last medical standard specifications has been designed exploiting the Venturi tube principle. A fully operating prototype has been tested, and data have been subsequently analyzed. Air flows up to 14 L/s can be measured with an accuracy of 0.2 L/s. Data acquisition software and user interface were developed.

Aerobic photosynthetic bacteria possess the unusual characteristic of producing different classes of carotenoids. In this study, we demonstrate the presence of two distinct crt gene clusters involved in the synthesis of spirilloxanthin and canthaxanthin in a Bradyrhizobium strain. Each cluster contains the genes crtE, crtB, and crtI leading to the common precursor lycopene. We show that spirilloxanthin is associated with the photosynthetic complexes, while canthaxanthin protects the bacteria from oxidative stress. Only the spirilloxanthin crt genes are regulated by light via the control of a bacteriophytochrome. Despite this difference in regulation, the biosyntheses of both carotenoids are strongly interconnected at the level of the common precursors. Phylogenetic analysis suggests that the canthaxanthin crt gene cluster has been acquired by a lateral gene transfer. This acquisition may constitute a major selective advantage for this class of bacteria, which photosynthesize only under conditions where harmful reactive oxygen species are generated.

An electronic device was fabricated consisting of 2 flexible electronic circuit islands, interconnected by a 7 cm long elastic interconnection, which could be elongated for at least 50%. This interconnection was based on gold conductor tracks following a 2-D spring pattern, embedded in a biocompatible silicone elastomer. The complete device was embedded in the same silicone elastomer. An in vitro cytotoxicity extraction test, executed on small test-samples in accordance with the ISO 10 993-1 guidelines, revealed that the applied silicone encapsulation to these samples functioned as a good seal for at least 8 days.

In the frame of the Flemish Community funded project Bioflex we developed and fabricated an implant for short term (< 7 days) bladder pressure monitoring, and diagnosis of incontinence. This implant is soft and flexible to prevent damaging the bladder’s inner wall. It contains a standard flexible electronic circuit connected to a battery, which are embedded in surface treated silicone to enhance the biocompatibility and prevent salt deposition. This article describes the fabrication of the pill and the results of preliminary cytotoxicity tests. The electronic design and its tests, implantation and the result of the in-vivo experimentation will be presented in other articles.