Nuclear Skins and Halos in the Mean-Field Theory

Nuclei with large neutron-to-proton ratios have neutron skins, which manifest themselves in an excess of neutrons at distances greater than the radius of the proton distribution. In addition, some drip-line nuclei develop very extended halo structures. The neutron halo is a threshold effect; it appears when the valence neutrons occupy weakly bound orbits. In this study, nuclear skins and halos are analyzed within the self-consistent Skyrme-Hartree-Fock-Bogoliubov and relativistic Hartree-Bogoliubov theories for spherical shapes. It is demonstrated that skins, halos, and surface thickness can be analyzed in a model-independent way in terms of nucleonic density form factors. Such an analysis allows for defining a quantitative measure of the halo size. The systematic behavior of skins, halos, and surface thickness in even-even nuclei is discussed.Comment: 22 RevTeX pages, 22 EPS figures included, submitted to Physical Review

Updated precision measurement of the average lifetime of B hadrons

The measurement of the average lifetime of B hadrons using inclusively reconstructed secondary vertices has been updated using both an improved processing of previous data and additional statistics from new data. This has reduced the statistical and systematic uncertainties and gives \tau_{\mathrm{B}} = 1.582 \pm 0.011\ \mathrm{(stat.)} \pm 0.027\ \mathrm{(syst.)}\ \mathrm{ps.} Combining this result with the previous result based on charged particle impact parameter distributions yields \tau_{\mathrm{B}} = 1.575 \pm 0.010\ \mathrm{(stat.)} \pm 0.026\ \mathrm{(syst.)}\ \mathrm{ps.

Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

Relationship of edge localized mode burst times with divertor flux loop signal phase in JET

A phase relationship is identified between sequential edge localized modes (ELMs) occurrence times in a set of H-mode tokamak plasmas to the voltage measured in full flux azimuthal loops in the divertor region. We focus on plasmas in the Joint European Torus where a steady H-mode is sustained over several seconds, during which ELMs are observed in the Be II emission at the divertor. The ELMs analysed arise from intrinsic ELMing, in that there is no deliberate intent to control the ELMing process by external means. We use ELM timings derived from the Be II signal to perform direct time domain analysis of the full flux loop VLD2 and VLD3 signals, which provide a high cadence global measurement proportional to the voltage induced by changes in poloidal magnetic flux. Specifically, we examine how the time interval between pairs of successive ELMs is linked to the time-evolving phase of the full flux loop signals. Each ELM produces a clear early pulse in the full flux loop signals, whose peak time is used to condition our analysis. The arrival time of the following ELM, relative to this pulse, is found to fall into one of two categories: (i) prompt ELMs, which are directly paced by the initial response seen in the flux loop signals; and (ii) all other ELMs, which occur after the initial response of the full flux loop signals has decayed in amplitude. The times at which ELMs in category (ii) occur, relative to the first ELM of the pair, are clustered at times when the instantaneous phase of the full flux loop signal is close to its value at the time of the first ELM

Spectroscopy of H-bonds in acetic acid crystals at 10K

As most quantitative information on H-bonds originates from studies on vs bands (O-H ... O), we describe the shapes of these specific bands at 10 K in the acetic acid crystal CH3COOH and in the isotopic analogs CD3COOH, CH3COOD and CD3COOD. From a comparison of the integrated transition probabilities, centres of gravity and variances of the bands of these four isotopic species, we can deduce that these vs modes show, besides their fundamental anharmonic couplings with vσ (O-H ... O) and some resonant couplings, a strong anharmonicity in νs, indicating an important amplitude vibration. A complete theoretical description of the shape of these bands will require further experimental results.Nous décrivons dans cet article les résultats d'une étude sur les bandes vs (O-H ... O) dans les cristaux d'acide acétique CH3COOH à 10 K ainsi que dans ses analogues deutériés CD3COOH, CH 3COOD et CD3COOD. Ces raies sont en effet la principale source d'information quantitative sur la liaison hydrogène. Par comparaison des probabilités de transition intégrées, centres de gravité et variances de ces bandes dans les quatre composés isotopiques nous déduisons que ces modes vs ont, en plus du couplage anharmonique fondamental avec v σ (O-H ... O) et éventuellement des couplages de résonance, une anharmonicité propre, qui traduit une amplitude de vibration anormalement grande. Des mesures supplémentaires seront cependant nécessaires pour arriver à une description théorique précise de la forme de ces bandes

Localized spraying in oilseeds rape crop with a conventional boom sprayer

National audienceAs a part of ECOPHYTO plan established by the French government to reduce the use of chemical plant protection products (PPP), specific spraying equipment are needed, for example to spray only the row of the crop. Often these devices have small spray boom widths and they are very expensive. The objectives of the project “PLEVOP” (development of in-row sprayer in oleaginous crops and protein crops), proposed by the technical Institute Terres-Inovia, are to define the conditions for successful localized post-emergence spraying for the herbicide application on the row using large width devices. This work is carried out in connection with a manufacturer of agricultural equipment (the Marechal company), an agricultural cooperative (CAL) and a French public Institution of Higher Education (AgroSup Dijon). The first year, experiences were conducted on oilseed rape crops using GPS-RTK as guidance system embedded on the tractor; the second year, trials were realized on oilseed rape and sunflower using a camera interface placed on the boom as guidance system. Three weeding strategies practices are compared: "full herbicide treatment" vs. "herbicide treatment on the row + inter-row hoeing" and a "no treatment". After weed counting and identification, we evaluated the biological efficiency on weeds and the effectiveness of such operations. Moreover, working with a conventional sprayer for a localized spraying, we have developed an automatic calculator tool to help farmer to determine the required amount of herbicide and water depending on its use conditions (nozzle type, nozzle height, speed of passage, boom height, field size, etc...). Oilseed rape: First trial of localized herbicide treatment with a conventional boom sprayer Experiences were conducted in the Lorraine region in France in 2017-2018 on oilseed rape crop. Plants were treated post-emergence with an herbicide at the stage four leaves. The sprayer was equipped with GPS-RTK as guidance system and the boom width was 16m (Figure 1). The sprayer characteristics were: nozzle=110°, boom height=16cm, spray band=45cm for the full herbicide treatment and nozzle=40°, boom height=27,5cm and spray band=20cm for the localized treatment. The results of this first year of experimentation show that localized treatment and full treatment have much lower infestations than the untreated reference. On the crop row, the infestations of the "localized treatment" and "full treatment" modalities are similar, which shows that on the crop row the localized treatment is as effective as a full treatment. On the inter-row, the modality " herbicide treatment on the row then hoeing" is slightly more infested in weeds than the inter-row of the modality "full treatment", which shows that the hoeing is slightly less satisfying than the full treatment. Nevertheless, when we compare the inter-row of the modality " localized treatment on the crop row and then hoeing in the inter-row" with the inter-row of the untreated reference, we notice a hoeing efficiency that is not negligible. In the modality "full treatment", we observe that the crop row is slightly dirtier than the interrow one can possibly interpret that by an umbrella effect of the rapeseed crop during the 195 treatment. In the untreated reference, we observe that the crop row is less dirty than the interrow; this is probably due to a competitive effect of rapeseed on weeds on the row. Thus, the results of modality "localized treatment on the row then hoeing" on oilseed rape crop are encouraging. The localized treatment area with no hoeing also shows that the treatment on the crop row is not enough to have a good efficiency overall surface and that hoeing is important. That is the complementarity of chemical weeding and mechanical weeding which makes it possible to obtain the 80% efficiency observed. Figure 1: Specific spraying equipment and spraying formula used for the PLEVOP project A Decision Support Tool for localized spraying A single conventional sprayer with a large spray boom (16 m) was used for both "full treatment" and "spot treatment" strategies. In both cases, complex calculations were made to determine exactly the amounts of herbicide and water. So we had to create a decision support tool (DST) to help farmers depending on their own spraying parameters but also to provide information about the environmental benefits of a localized spraying (Treatment Frequency Index (TFI) reduction for example). As an example, considering the spray parameters described previously for both treatment (full and localized) and according a tractor speed of 10km/h, a nozzle output of 0.65l/min and using an herbicide product (2litre/ha) the results of calculation are deduced from the decision support tool. They indicate that: for the "full treatment", 86.7litre of water and 2litre of herbicide are required for a field of one hectare whereas as for the treatment on the row strategy, with a spray band of 20cm, only 0.89litre of herbicide and 86.7litre of water are required for a field of one hectare. Conclusions and Future Outlook We have tested in rapeseed crop, the use of a single conventional sprayer with a spray boom of 16m for a full and localized herbicide treatment thanks to a GPS-RKT type guidance system. The "full treatment" and "localized treatment" modalities were compared to the reference "no treatment". Results were encouraging, demonstrating that "localized treatment on the crop row then hoeing" is as efficient as "full treatment" modality. During experiences, the spraying settings had to be changed for the automatic calculations of herbicide and water quantities. The guidance system with a camera interface has to be evaluated as well. Overall, we developed a decision support tool (DST) in order to assist farmers in the volume calculations of whatever their spraying settings. Thus, environmental benefits have been added to sensitize the farmer to the positive effects of herbicide reduction. We would also like to finalize the decision support tool with an economic cost estimation. Finally, we would like to test our system on other crops (protein crops for example) and using other phytopharmaceutical products

P.1.f.007 Alexithymia in severe obese patients

International audienc

SARS-CoV-2 Genome Quantification in Wastewaters at Regional and City Scale Allows Precise Monitoring of the Whole Outbreaks Dynamics and Variants Spreading in the Population

SARS-CoV-2 is a coronavirus causing a globalized outbreak called COVID-19. SARS-CoV-2 transmission is associated with inhalation of contaminated respiratory droplets and could causes severe complications. Until today several “waves” of infections have been observed despite implementation of strict health policies. Decisions for such sanitary measures are based on population health monitoring. Unfortunately, for COVID-19, a significant proportion of individuals are asymptomatic but play a role in the virus transmission. To overcome these limitations, several strategies were developed including genome quantification in wastewater that could allow monitoring of the health status of population, since shedding of SARS-CoV-2 in patient stool is frequent. Wastewater-based epidemiology (WBE) was established and several countries implemented this approach to allow COVID-19 outbreak monitoring. In France, the OBEPINE project performed a quantitative analysis of SARS-CoV-2 in raw wastewater samples collected from major wastewater treatment plants (WWTP) since March 2020. In the greater Paris area 1101 samples (507 for five WWTP and 594 for sewer) were collected. This 16 months monitoring allows us to observe the outbreak dynamics. Comparison of WBE indicators with health data lead to several important observation; the good level of correlation with incidence rates, the average 3 days lead time, and the sensitivity (WBE change when incidence is > to 7/100000 inhabitants). We also compared the local monitoring (city level) with the regional monitoring, to help cluster identification. Moreover, variants of concern (VOC) emerged due to the selection pressure. We developed a specific RT-qPCR method targeting the deletion H69-V70 in the spike protein, using this deletion as a proxy of the B.1.1.7 presence in the wastewater. With this data we demonstrate the predominant role played by this strain in the third wave. All these results allow a better description and understanding of the pandemic and highlight the role of such WBE indicators