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International audience; Hydrological variations hold a significant influence over the water chemistry in the karst systems within the critical zone. In this context, the Baget Catchment (BC) was monitored at highresolution over two hydrological years. The high-frequency survey at the outlet of BC displayed multiple hydrochemical patterns in response to hydrological variations, mixing water sources, and biogeochemical processes. Among the major elements, sulfate exhibited the widest relative variation during flooding and showed a significant dilution, whereas calcium and bicarbonate revealed a chemostatic behavior as a result of carbonate dissolution in the karst. Hysteretic analysis evidenced the control of different hydrological reservoirs over the stream transport processes of dissolved elements. The concentration of dissolved organic carbon increased during the hydrograph rising limb and was controlled by surface runoff. The relationships between Ca 2+ and HCO3concentrations and stream-discharge exhibited hysteresis patterns with counterclockwise loops, unlike all other elements, due to the carbonate weathering by biogenic CO2-rich water. Finally, highfrequency sampling during storm events improved the understanding of the factors controlling the hydrochemical dynamic of the Baget stream water. The relative contributions of the karst and epikarst zones, of rainwater, as well as the role of different biogeochemical processes and the hydrological conditions were highlighted.

The transfer of sufficient immunoglobulin G (IgG) to the neonatal calf through colostrum is essential to provide the calf with immunological protection and resistance against disease. Studies on the efficiency of colstrum intake and levels of IgG absorption in calves reared with cow contact are contradictory . On-farm trials were conducted in Switzerland (CH) and France (FR) to test if (1) passive transfer of immunity from cows to calves and (2) if immune (IgG) and antimicrobial (lactoferrin content=LF) parameters in dairy cows’ milk would change by nursing. Calves’ plasma and milk from cows being milked and additionally suckled twice daily for 30 minutes after milking (CH) or between morning and evening milking (FR) was compared to milk from dairy cows only milked. In CH trials IgG content in calf serum did not differ between feeding groups at any observation point, but showed a clear change over time in form of a marked drop followed by an increase again. This was mainly due to the fact that colostrum mangement between suckling and teat bucket fed calves did not differ in these trials. In FR, the IgG concentration in calves’ serum was similar in the different groups and no interaction was observed with the week. The passive immunity transfer was adequate for most calves, except for 3, 2 and 4 calves (out of 14) in groups Control, Dam and Mixed respectively whose plasma IgG concentration was below the threshold of 10 g/L (Besser et al., 1991). The plasma IgG concentration decreased significantly from week 3 to 10 and was significantly higher in female than in male calves. In Swiss trials neither IgG content (mg/L) nor lactoferrin content (LF) in cows' milk differed between feeding regimes. While IgG considerably decreased after 3 weeks, LF content stayed constant, but was more variable in nursing cows. By contrast, in French trials milk IgG was significantly higher in Mixed-cows in week 3, compared to Control and Dam-cows. This finding is very surprising considering that in week 3, all Mixed and Dam cows were suckling their calves. Therefore, differences do not seem to be due to calves’ suckling. Further investigations need to be done in order to try to understand the French results. Also contrary to the Swiss results, milk LF concentration increased steadily from week 3 to 13 and in Week 13. Milk LF was significantly higher in Control cows compared to Dam and Mixed-cows. Again, this result is very surprising and does not seem to be related to calves’ suckling as in week 13, all calves were weaned in all groups. Here again, further investigation needs to be done in order to try to understand this result that could be linked to milk SCC, slightly higher in average in Control cows in week 13.

The increasing importance of well-controlled ordered nanostructures on surfaces represents a challenge for existing metrology techniques. To develop such nanostructures and monitor complex processing constraints fabrication, both a dimensional reconstruction of nanostructures and a characterization (ideally a quantitative characterization) of their composition is required. In this work, we present a soft X-ray fluorescence-based methodology that allows both of these requirements to be addressed at the same time. By applying the grazing-incidence X-ray fluorescence technique and thus utilizing the X-ray standing wave field effect, nanostructures can be investigated with a high sensitivity with respect to their dimensional and compositional characteristics. By varying the incident angles of the exciting radiation, element-sensitive fluorescence radiation is emitted from different regions inside the nanoobjects. By applying an adequate modeling scheme, these datasets can be used to determine the nanostructure characteristics. We demonstrate these capabilities by performing an element-sensitive reconstruction of a lamellar grating made of Si$_3$N$_4$, where GIXRF data for the O-K$\alpha$ and N-K$\alpha$ fluorescence emission allows a thin oxide layer to be reconstructed on the surface of the grating structure. In addition, we employ the technique also to three dimensional nanostructures and derive both dimensional and compositional parameters in a quantitative manner., Comment: 7 pages, 7 figures

Stream carbon fluxes are one of the major components in the global C cycle, yet the discrimination of the various sources of stream carbon remains to a large extent unclear and less is known about the biogeochemical transformations that accompany the transfer of C from soils to streams. Here, we used patterns in stream water and groundwater delta C-13 values in a small forested tropical headwater catchment to investigate the source and contribution from the soil carbon pools to stream organic and inorganic carbon behavior over seasonal scales. Stream organic carbon (DOC and POC) comes mainly from the upper rich soil organic carbon horizons and derived from total organic carbon (TOC) of biogenic source. The isotopic compositions delta C-13(TOC), delta C-13(DOC) and delta C-13(POC) of these carbon species were very close (-30 parts per thousand to -26 parts per thousand) and typical of the forested C3 vegetation. The relationship observed between DOC and log pCO(2) and delta C-13(DIC) indicated that besides the considerable CO2 evasion that occurs as DIC is transported from soils to streams, there were also other processes affecting the stream DIC pool. In-stream mineralization of DOC and mixing of atmospheric carbon had a significant influence on the delta C-13(DIC) values. These processes which varied seasonally with hydrological changes represent the main control on DOC and DIC cycling in the wet tropical milieu. The rapid turnover of carbon on hillside soils, the transformation of TOC to DOC in wetland soils and further mineralization of stream DOC to DIC favor the evasion of C, making the zone a source of carbon to the atmosphere.

In this study, grazing incidence small-angle X-ray scattering (GISAXS) is used to collect statistical information on dimensional parameters in an area of 20 mm x 15 mm on photonic structures produced by nanoimprint lithography. The photonic structures are composed of crystalline and locally quasicrystalline two-dimensional patterns with structure sizes between about 100 nm and 10 $\mu$m to enable broadband visible light absorption for use in solar energy harvesting. These first GISAXS measurements on locally quasicrystalline samples demonstrate that GISAXS is capable of showing the locally quasicrystalline nature of the samples while at the same time revealing the long-range periodicity introduced due to the lattice design. We describe the scattering qualitatively in the framework of the distorted wave Born approximation using a hierarchical model mirroring the sample design, which consists of a rectangular and locally quasicrystalline supercell which is repeated periodically to fill the whole surface. The nanoimprinted samples are compared to a sample manufactured using electron beam lithography and the distortions of the periodic and locally quasiperiodic samples are quantified statistically. Due to the high sensitivity of GISAXS to deviations from the perfect lattice, the misalignment of the crystallographic axes was measured with a resolution of 0.015{\deg}, showing distortions up to +/- 0.15{\deg} in the investigated samples.

recherche alimentaire dans une plantation de Palmiste blanc, Dictyosperma album (Bory) H. Wendl. & Drude ex Scheff., 1875. L'un d'eux a déniché à la base des premières folioles d'une palme, un orthoptère vert pomme, portant de longues antennes et d'une longueur estimée à moins de 30 mm. Il s'agit de Paradecolya inexspectata (Chopard, 1957) une espèce d'orthoptère de la famille des Tettigoniidae, endémique de La Réunion (Hugel, 2015). Signalons que le Genre Paradecolya Jin, 1992 est endémique des Mascareignes et contient deux autres taxa distribués à l'île Maurice: P. briseferiHugel, 2010 et P. expectataHugel, 2010(Jin & Keva, 1992). Si les orthoptera étaient déjà connus dans le régime alimentaire des zostérops, c'est la première fois que l'on peut identifier l'une de ses proies jusqu'à l'espèce. Enfin, nous tenons à signaler qu'à proximité d'une zone forestière indigène et protégée, une activité agricole qui respecte certains critères (non utilisation de pesticides, plantation de palmistes endémiques, conservation d'une végétation spontanée) est susceptible d'intégrerdes espèces indigènes et favorise le maintien de populations d'arthopodes patrimoniaux et d'interactions trophiques originelles. Ici, on peut remarquer le rôle salutaire de cette plantation de palmistes endémiques sur la sauterelle autochtone, au contraire des plantations d'espèces introduites comme le Camphrier, Cinnamomum camphora(L.) J.Presl, 1825, bien plus pauvres en biodiversité. Nous remercions Christophe Thébaud, Samuel Couteyen et Jacques Rochat pour leurs conseils et commentaires avisés.