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A non-standing characteristic of directly imaged spin-waves in confined micrometer-sized ultrathin Permalloy (Ni 80 Fe 20) structures is reported along with evidence of the possibility to alter the observed state by modifications to the sample geometry. Using micromagnetic simulations, the presence of the spin-wave modes excited in the Permalloy stripes along with the quasi-uniform modes was observed. The predicted spin-waves were imaged in direct space using time resolved scanning transmission X-ray microscopy, combined with a ferromagnetic resonance excitation scheme (STXM-FMR). STXM-FMR measurements revealed a non-standing characteristic of the spin-waves. Also, it was shown by micromagnetic simulations and confirmed using STXM-FMR results that the observed characteristic of the spin-waves can be influenced by the local magnetic fields in different sample geometries.

We present the element-specific and time resolved visualization of uniform ferromagnetic resonance excitations of a Permalloy (Py) disk-Cobalt (Co) stripe bilayer microstructure. The transverse high frequency component of the resonantly excited magnetization is sampled in the ps regime by a combination of ferromagnetic resonance (FMR) and scanning transmission X-ray microscopy (STXM-FMR) recording snapshots of the local magnetization precession of Py and Co with nanometer spatial resolution. The approach allows us to individually image the resonant dynamic response of each element, and we find that angular momentum is transferred from the Py disk to the Co stripe and vice versa at their respective resonances. The integral (cavity) FMR spectrum of our sample shows an unexpected additional third resonance. This resonance is observed in the STXM-FMR experiments as well. Our microscopic findings suggest that it is governed by magnetic exchange between Py and Co, showing for the Co stripe a difference in relative phase of the magnetization due to stray field influence., (© 2022. The Author(s).)

(1) Background: Pediatric sarcoidosis is a rare and mostly severe disease. Very few pediatric series with a prolonged follow-up are reported. We aimed to evaluate the evolution of pediatric sarcoidosis in adulthood. (2) Material and methods: Patients over 18-years-old with a pediatric-onset sarcoidosis (≤15-year-old) who completed at least a three-year follow-up in French expert centers were included. Clinical information at presentation and outcome in adulthood were studied. (3) Results: A total of 52 patients were included (34 prospectively in childhood and 18 retrospectively in adulthood), with a mean age of 12 (±2.7) at diagnosis. The median duration time of follow-up was 11.5 years (range 3-44.5). Relapses mostly occurred during treatment decrease (84.5%), others within the three years after treatment interruption (9.1%), and rarely when the disease was stable for more than three years (6.4%). Sarcoidosis was severe in 11 (21.2%) in adulthood. Patients received a high corticosteroid cumulative dose (median 17,900 mg) for a median duration of five years (range 0-32), resulting in mostly mild (18; 35.3%) and rarely severe (2; 3.8%) adverse events. (4) Conclusions: Pediatric-onset sarcoidosis needed a long-term treatment in almost half of the patients. Around one fifth of pediatric-onset sarcoidosis patients had severe sarcoidosis consequences in adulthood., Competing Interests: F.C.-A. is the PI of an academic study of the efficacy of infliximab in extrapulmonary sarcoidosis. T.A. reports personal fees from Chiesi, other from Vital Aire, other from Astrazeneca, other from Boehringer Ingelheim, outside the submitted work. D.V. reports personal fees from Roche, personal fees from Boehringer Ingelheim, outside the submitted work. N.N. reports grants from Société de pneumologie pédiatrique et d’allergologie (France), outside the submitted work. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. All others authors declared no direct conflict of interest related to the present work.

Strong unidirectional anisotropy in bulk polycrystalline B20 FeGe has been measured by ferromagnetic resonance spectroscopy. Such anisotropy is not present in static magnetometry measurements. B20 FeGe exhibits inherent Dzyaloshinskii-Moriya interaction, resulting in a nonreciprocal spin-wave dispersion. Bulk and micron sized samples were produced and characterized. By X-band ferromagnetic resonance spectroscopy at 276 K ± 1 K, near the Curie temperature, a distribution of resonance modes was observed in accordance with the cubic anisotropy of FeGe. This distribution exhibits a unidirectional anisotropy, i.e. shift of the resonance field under field inversion, of K UD  = 960 J/m 3  ± 10 J/m 3 , previously unknown in bulk ferromagnets. Additionally, more than 25 small amplitude standing spin wave modes were observed inside a micron sized FeGe wedge, measured at 293 K ± 2 K. These modes also exhibit unidirectional anisotropy. This effect, only dynamically measurable and not detectable in static magnetometry measurements, may open new possibilities for directed spin transport in chiral magnetic systems.

Spin wave logic circuits using quantum oscillations of spins (magnons) as carriers of information have been proposed for next generation computing with reduced energy demands and the benefit of easy parallelization. Current realizations of magnonic devices have micrometer sized patterns. Here we demonstrate the feasibility of biogenic nanoparticle chains as the first step to truly nanoscale magnonics at room temperature. Our measurements on magnetosome chains (ca 12 magnetite crystals with 35 nm particle size each), combined with micromagnetic simulations, show that the topology of the magnon bands, namely anisotropy, band deformation, and band gaps are determined by local arrangement and orientation of particles, which in turn depends on the genotype of the bacteria. Our biomagnonic approach offers the exciting prospect of genetically engineering magnonic quantum states in nanoconfined geometries. By connecting mutants of magnetotactic bacteria with different arrangements of magnetite crystals, novel architectures for magnonic computing may be (self-) assembled.

Microbial communities are the driving force behind the degradation of contaminants like aromatic hydrocarbons in groundwater ecosystems. However, little is known about the response of native microbial communities to contamination in pristine environments as well as their potential to recover from a contamination event. Here, we used an indoor aquifer mesocosm filled with sandy quaternary calciferous sediment that was continuously fed with pristine groundwater to study the response, resistance and resilience of microbial communities to toluene contamination over a period of almost two years, comprising 132days of toluene exposure followed by nearly 600days of recovery. We observed an unexpectedly high intrinsic potential for toluene degradation, starting within the first two weeks after the first exposure. The contamination led to a shift from oxic to anoxic, primarily nitrate-reducing conditions as well as marked cell growth inside the contaminant plume. Depth-resolved community fingerprinting revealed a low resistance of the native microbial community to the perturbation induced by the exposure to toluene. Distinct populations that were dominated by a small number of operational taxonomic units (OTUs) rapidly emerged inside the plume and at the plume fringes, partially replacing the original community. During the recovery period physico-chemical conditions were restored to the pristine state within about 35days, whereas the recovery of the biological parameters was much slower and the community composition inside the former plume area had not recovered to the original state by the end of the experiment. These results demonstrate the low resilience of sediment-associated groundwater microbial communities to organic pollution and underline that recovery of groundwater ecosystems cannot be assessed solely by physico-chemical parameters., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Clostridium difficile causes antibiotic-associated diarrhoea and pseudomembranous colitis. The main virulence factors of C. difficile are the toxins A (TcdA) and B (TcdB). A third toxin, called binary toxin (CDT), can be detected in 17% to 23% of strains, but its role in human disease has not been clearly defined. We report six independent cases of patients with diarrhoea suspected of having C. difficile infection due to strains from toxinotype XI/PCR ribotype 033 or 033-like, an unusual toxinotype/PCR ribotype positive for CDT but negative for TcdA and TcdB. Four patients were considered truly infected by clinicians and were specifically treated with oral metronidazole. One of the cases was identified during a prevalence study of A(-)B(-)CDT(+) strains. In this study, we screened a French collection of 220 nontoxigenic strains and found only one (0.5%) toxinotype XI/PCR ribotype 033 or 033-like strain. The description of such strains raises the question of the role of binary toxin as a virulence factor and could have implications for laboratory diagnostics that currently rarely include testing for binary toxin.

We describe a 17-year-old patient presenting perimyocarditis as the initial manifestation of the adult-onset Still's disease. Corticotherapy was rapidly successful but induced major acute hepatitis in relation with Epstein-Barr virus reactivation. After 1 year, even if the global outcome is favourable, a slightly lowered ejection fraction still persists. Former case reports and differential diagnosis with reactive haemophagocytic syndrome would be discussed.

There are many similarities between mycobacteriosis, in particular, tuberculosis, and sarcoidosis such as predominant intrathoracic localisation (even if all organs and tissues may be concerned), great variability of phenotypic expression, and granulomatous inflammatory reaction, caseous necrosis not being an absolute criterion of tuberculosis. Moreover, microbial (or mycobacterial?) agents may play a role in the pathogenesis of sarcoidosis which remains a diagnosis of exclusion particularly in atypical cases. The authors report a case of a non-immunocompromised female patient who presented, simultaneously, isolated axillary tubercular adenitis and neuro-sarcoidosis without any other localisation. This case illustrates the difficulty to distinguish between both of these two diseases and thus to choose an adequate treatment when diagnosis is not proven. Moreover, our patient (human leucocyte antigen B27 positive) presented symptoms of spondylarthritis which also may have a nosological link with tuberculosis or sarcoidosis.

In recent years, compound specific isotope analyses (CSIA) have developed into one of the most powerful tools for the quantification of in situ biodegradation of organic contaminants. In this approach, the calculation of the extent of biodegradation of organic contaminants in aquifers is usually based on the Rayleigh equation, and thus neglects physical transport processes such as dispersion that contribute to contaminant dilution in aquifers. Here we combine compound specific isotope analyses with a conservative transport model to study the attenuation of aromatic hydrocarbons at a former gasworks site. The conservative transport model was first used to simulate concentration reductions caused by dilution at wells downgradient of a BTEX source. In a second step, the diluted concentrations, together with the available stable carbon isotope ratios and carbon fractionation factors for benzene, toluene and o-xylene were applied in the Rayleigh equation to quantify the degree of biodegradation at each of those wells. At the investigated site, where other attenuation processes such as sorption and volatilisation were proven to be negligible, the combined approach is recommended for benzene, which represents a compound for which the effect of biodegradation is comparable to or less than the effect of dilution. As demonstrated for toluene and o-xylene, the application of the Rayleigh equation alone is sufficient if dilution can be proved to be insignificant in comparison to biodegradation. The analysis also suggests that the source width and the position of the observation wells relative to the plume center line are significantly related to the degree of dilution.

Fractionation of stable carbon isotopes upon degradation of trichlorobenzenes was studied under aerobic and anaerobic conditions. Mineralization of 1,2,4-trichlorobenzene by the aerobic strain Pseudomonas sp. P51 which uses a dioxygenase for the initial enzymatic reaction was not accompanied by a significant isotope fractionation. In contrast, reductive dehalogenation by the anaerobic strain Dehalococcoides sp. strain CBDB1 revealed average isotope enrichment factors (eta) between -3.1 and -3.7 for 1,2,3- and 1,2,4-trichlorobenzene, respectively. The significant isotope fractionation during reductive dehalogenation would allow tracing the in situ biodegradation of halogenated benzenes in contaminated anoxic aquifers, whereas the lack of isotope fractionation during aerobic transformation limits the use of this approach in oxic environments.

A concept to assess in situ biodegradation of organic contaminants in aquifers is presented. The alteration of the carbon isotope composition of contaminants along the groundwater flow path indicates microbial degradation processes and can be used as an indicator for in situ biodegradation. The Rayleigh equation was applied to calculate the percentage of the in situ biodegradation (B[%]) using the change in the isotopic composition of contaminants (Rt/R0) along the ground water flow path and a kinetic carbon isotope fractionation factor (alphaC) derived from defined biodegradation experiments in the laboratory. When the groundwater hydrology is known and a representative source concentration (C0) for a groundwater flow path can be determined, the extent of in situ biodegradation can be quantified.

Anaerobic cometabolic conversion of benzothiophene was studied with a sulfate-reducing enrichment culture growing with naphthalene as the sole source of carbon and energy. The sulfate-reducing bacteria were not able to grow with benzothiophene as the primary substrate. Metabolite analysis was performed with culture supernatants obtained by cometabolization experiments and revealed the formation of three isomeric carboxybenzothiophenes. Two isomers were identified as 2-carboxybenzothiophene and 5-carboxybenzothiophene. In some experiments, further reduced dihydrocarboxybenzothiophene was identified. No other products of benzothiophene degradation could be determined. In isotope-labeling experiments with a [(13)C]bicarbonate-buffered culture medium, carboxybenzothiophenes which were significantly enriched in the (13)C content of the carboxyl group were formed, indicating the addition of a C(1) unit from bicarbonate to benzothiophene as the initial activation reaction. This finding was consistent with the results of earlier studies on anaerobic naphthalene degradation with the same culture, and we therefore propose that benzothiophene was cometabolically converted by the same enzyme system. Groundwater analyses of the tar-oil-contaminated aquifer from which the naphthalene-degrading enrichment culture was isolated exhibited the same carboxybenzothiophene isomers as the culture supernatants. In addition, the benzothiophene degradation products, in particular, dihydrocarboxybenzothiophene, were significantly enriched in the contaminated groundwater to concentrations almost the same as those of the parent compound, benzothiophene. The identification of identical metabolites of benzothiophene conversion in the sulfate-reducing enrichment culture and in the contaminated aquifer indicated that the same enzymatic reactions were responsible for the conversion of benzothiophene in situ.

Primary features of hydrogen and carbon isotope fractionation during toluene degradation were studied to evaluate if analysis of isotope signatures can be used as a tool to monitor biodegradation in contaminated aquifers. D/H hydrogen isotope fractionation during microbial degradation of toluene was measured by gas chromatography. Per-deuterated toluene-d(8) and nonlabeled toluene were supplied in equal amounts as growth substrates, and kinetic isotope fractionation was calculated from the shift of the molar ratios of toluene-d(8) and nondeuterated toluene. The D/H isotope fractionation varied slightly for sulfate-reducing strain TRM1 (slope of curve [b] = -1.219), Desulfobacterium cetonicum (b = -1.196), Thauera aromatica (b = -0.816), and Geobacter metallireducens (b = -1.004) and was greater for the aerobic bacterium Pseudomonas putida mt-2 (b = -2.667). The D/H isotope fractionation was 3 orders of magnitude greater than the (13)C/(12)C carbon isotope fractionation reported previously. Hydrogen isotope fractionation with nonlabeled toluene was 1.7 and 6 times less than isotope fractionation with per-deuterated toluene-d(8) and nonlabeled toluene for sulfate-reducing strain TRM1 (b = -0.728) and D. cetonicum (b = -0.198), respectively. Carbon and hydrogen isotope fractionation during toluene degradation by D. cetonicum remained constant over a growth temperature range of 15 to 37 degrees C but varied slightly during degradation by P. putida mt-2, which showed maximum hydrogen isotope fractionation at 20 degrees C (b = -4.086) and minimum fractionation at 35 degrees C (b = -2.138). D/H isotope fractionation was observed only if the deuterium label was located at the methyl group of the toluene molecule which is the site of the initial enzymatic attack on the substrate by the bacterial strains investigated in this study. Use of ring-labeled toluene-d(5) in combination with nondeuterated toluene did not lead to significant D/H isotope fractionation. The activity of the first enzyme in the anaerobic toluene degradation pathway, benzylsuccinate synthase, was measured in cell extracts of D. cetonicum with an initial activity of 3.63 mU (mg of protein)(-1). The D/H isotope fractionation (b = -1.580) was 30% greater than that in growth experiments with D. cetonicum. Mass spectroscopic analysis of the product benzylsuccinate showed that H atoms abstracted from the toluene molecules by the enzyme were retained in the same molecules after the product was released. Our findings revealed that the use of deuterium-labeled toluene was appropriate for studying basic features of D/H isotope fractionation. Similar D/H fractionation factors for toluene degradation by anaerobic bacteria, the lack of significant temperature dependence, and the strong fractionation suggest that analysis of D/H fractionation can be used as a sensitive tool to assess degradation activities. Identification of the first enzyme reaction in the pathway as the major fractionating step provides a basis for linking observed isotope fractionation to biochemical reactions.

Anaerobic degradation of 2-methylnaphthalene was investigated with a sulfate-reducing enrichment culture. Metabolite analyses revealed two groups of degradation products. The first group comprised two succinic acid adducts which were identified as naphthyl-2-methyl-succinic acid and naphthyl-2-methylene-succinic acid by comparison with chemically synthesized reference compounds. Naphthyl-2-methyl-succinic acid accumulated to 0.5 microM in culture supernatants. Production of naphthyl-2-methyl-succinic acid was analyzed in enzyme assays with dense cell suspensions. The conversion of 2-methylnaphthalene to naphthyl-2-methyl-succinic acid was detected at a specific activity of 0.020 +/- 0.003 nmol min(-1) mg of protein(-1) only in the presence of cells and fumarate. We conclude that under anaerobic conditions 2-methylnaphthalene is activated by fumarate addition to the methyl group, as is the case in anaerobic toluene degradation. The second group of metabolites comprised 2-naphthoic acid and reduced 2-naphthoic acid derivatives, including 5,6,7,8-tetrahydro-2-naphthoic acid, octahydro-2-naphthoic acid, and decahydro-2-naphthoic acid. These compounds were also identified in an earlier study as products of anaerobic naphthalene degradation with the same enrichment culture. A pathway for anaerobic degradation of 2-methylnaphthalene analogous to that for anaerobic toluene degradation is proposed.

Anaerobic naphthalene degradation by a sulfate-reducing enrichment culture was studied by substrate utilization tests and identification of metabolites by gas chromatography-mass spectrometry. In substrate utilization tests, the culture was able to oxidize naphthalene, 2-methylnaphthalene, 1- and 2-naphthoic acids, phenylacetic acid, benzoic acid, cyclohexanecarboxylic acid, and cyclohex-1-ene-carboxylic acid with sulfate as the electron acceptor. Neither hydroxylated 1- or 2-naphthoic acid derivatives and 1- or 2-naphthol nor the monoaromatic compounds ortho-phthalic acid, 2-carboxy-1-phenylacetic acid, and salicylic acid were utilized by the culture within 100 days. 2-Naphthoic acid accumulated in all naphthalene-grown cultures. Reduced 2-naphthoic acid derivatives could be identified by comparison of mass spectra and coelution with commercial reference compounds such as 1,2,3, 4-tetrahydro-2-naphthoic acid and chemically synthesized decahydro-2-naphthoic acid. 5,6,7,8-Tetrahydro-2-naphthoic acid and octahydro-2-naphthoic acid were tentatively identified by their mass spectra. The metabolites identified suggest a stepwise reduction of the aromatic ring system before ring cleavage. In degradation experiments with [1-(13)C]naphthalene or deuterated D(8)-naphthalene, all metabolites mentioned derived from the introduced labeled naphthalene. When a [(13)C]bicarbonate-buffered growth medium was used in conjunction with unlabeled naphthalene, (13)C incorporation into the carboxylic group of 2-naphthoic acid was shown, indicating that activation of naphthalene by carboxylation was the initial degradation step. No ring fission products were identified.