Magneto-transport properties of monolayer borophene in perpendicular magnetic field: influence of electron-phonon interaction

The magneto-transport properties of a borophene monolayer in a perpendicular magnetic field B are studied via calculating the conductivity tensor and resistance under electron-optical phonon interaction by using the linear response theory. Numerical results are obtained and discussed for some specific parameters. The magnetic field-dependent longitudinal conductivity shows the magneto-phonon resonance effect that describes the transition of electrons between Landau levels by absorbing/emitting an optical phonon. The Hall conductivity increases first and then decreases with the magnetic field strength. Also, the longitudinal resistance increases significantly with increasing temperature, which shows the metal behaviour of the material. Practically, the observed magneto-phonon resonance can be applied to experimentally determine some material parameters, such as the distance between Landau levels and the optical phonon energy

NIKA2 observations of dust grain evolution from star-forming filament to T-Tauri disk: Preliminary results from NIKA2 observations of the Taurus B211/B213 filament

To understand the evolution of dust properties in molecular clouds in the course of the star formation process, we constrain the changes in the dust emissivity index from star-forming filaments to prestellar and protostellar cores to T Tauri stars. Using the NIKA2 continuum camera on the IRAM 30~m telescope, we observed the Taurus B211/B213 filament at 1.2\,mm and 2\,mm with unprecedented sensitivity and used the resulting maps to derive the dust emissivity index $\beta$. Our sample of 105 objects detected in the $\beta$ map of the B211/B213 filament indicates that, overall, $\beta$ decreases from filament and prestellar cores ($\beta \sim 2\pm0.5$) to protostellar cores ($\beta \sim 1.2 \pm 0.2$) to T-Tauri protoplanetary disk ($\beta < 1$). The averaged dust emissivity index $\beta$ across the B211/B213 filament exhibits a flat ($\beta \sim 2\pm0.3$) profile. This may imply that dust grain sizes are rather homogeneous in the filament, start to grow significantly in size only after the onset of the gravitational contraction/collapse of prestellar cores to protostars, reaching big sizes in T Tauri protoplanetary disks. This evolution from the parent filament to T-Tauri disks happens on a timescale of about 1-2~Myr.Comment: to appear in Proc. of the mm Universe 2023 conference, Grenoble (France), June 2023, published by F. Mayet et al. (Eds), EPJ Web of conferences, EDP Science

NIKA2 observations of dust grain evolution from star-forming filament to T-Tauri disk: Preliminary results from NIKA2 observations of the Taurus B211/B213 filament

To understand the evolution of dust properties in molecular clouds in the course of the star formation process, we constrain the changes in the dust emissivity index from star-forming filaments to prestellar and protostellar cores to T Tauri stars. Using the NIKA2 continuum camera on the IRAM 30 m telescope. we observed the Taurus B211/B2I3 filament at 1.2 mm and 2 mm with unprecedented sensitivity and used the resulting maps to derive the dust emissivity index β. Our sample of 105 objects detected in the β map of the B211/B213 filament indicates that, overal. β decreases from filament and prestellar cores (β ~ 2 ± 0.5) to protostellar cores (β ~ 1.2 ± 0.2) to T-Tauri protoplanetary disk (β < I). The averaged dust emissivity index β across the B211/B2I3 filament exhibits a flat (β ~ 2 ± 0.3) profile. This may imply that dust grain sizes are rather homogeneous in the filament, start to grow significantly in size only after the onset of the gravitational contraction/collapse of prestellar cores to protostars, reaching big sizes in T Tauri protoplanetary disks. This evolution from the parent filament to T-Tauri disks happens on a timescale of about 1-2 Myr

Vision, challenges and opportunities for a Plant Cell Atlas

With growing populations and pressing environmental problems, future economies will be increasingly plant-based. Now is the time to reimagine plant science as a critical component of fundamental science, agriculture, environmental stewardship, energy, technology and healthcare. This effort requires a conceptual and technological framework to identify and map all cell types, and to comprehensively annotate the localization and organization of molecules at cellular and tissue levels. This framework, called the Plant Cell Atlas (PCA), will be critical for understanding and engineering plant development, physiology and environmental responses. A workshop was convened to discuss the purpose and utility of such an initiative, resulting in a roadmap that acknowledges the current knowledge gaps and technical challenges, and underscores how the PCA initiative can help to overcome them.</jats:p

Sociodemographic Factors Associated with Request for Labor Epidural Analgesia in a Tertiary Obstetric Hospital in Vietnam

This study is aimed at examining the sociodemographic factors associated with the utilization of labor epidural analgesia at a large obstetric and gynecology hospital in Vietnam. This was a cross-sectional study of women who underwent vaginal delivery in September 2018 at the Hanoi Obstetrics and Gynecology Hospital. The utilization of epidural analgesia during labor was determined. Univariate and multivariate regression models were applied to evaluate the association between patient demographic and socioeconomic factors and request for labor epidural analgesia. A total of 417 women had vaginal deliveries during the study period. 207 women utilized epidural analgesia for pain relief during labor, and 210 did not. Parturients older than 35 years of age (OR 2.84, 95% CI 1.11-8.17), multiparous women (OR 2.8 95% CI 1.85-4.25), women living from an urban area, women with higher income (OR 6.47, 95% CI 2.59-19.23), and women with higher level of education were more likely to utilize labor epidurals. Factors related to a parturient request for epidural analgesia during labor at our tertiary obstetric hospital included age greater than 35 years, multiparity, and high income and education levels. Educational outreach to women about the benefits of epidural analgesia can target women who do not share these demographic characteristics

Use of the new dynamic cone penetrometer for the study of soil liquefaction along the Kupa River, Petrinja area (Croatia)

Voir également : https://irsn.hal.science/hal-04414299v1International audienceDuring the Petrinja earthquake sequence in December 2020, numerous liquefied sand ejections came to the surface along the Kupa, Sava and Glina rivers in Quaternary alluvial sediments. In October 2022, we performed field investigation in the epicentral area, involving geotechnical and geophysical techniques, at different sites with sand ejecta or lateral spreading along the Kupa river. Geotechnical soundings were carried out with variable energy dynamic cone penetrometer. We used both Light Dynamic Penetrometer (DPL-Panda) and its Super Heavy version (DPSH-Grizzly), to evaluate the soil characteristics and to specify the geometries of the various subsurface sedimentary layers. This paper presents one of the ground site models based on DPL and DPSH tests along with Electrical Resistivity Tomography (ERT) profiles. The resulting models will contribute to a better understanding of mechanical characteristics of soils and their potential to liquef

Preliminary results of geotechnical and geophysical investigations on sites with liquefaction occurrences in the greater Petrinja area after the 2020 earthquake

Voir aussi : https://irsn.hal.science/hal-04414348vInternational audienceThe occurrence of extensive liquefaction during the 2020 Petrinja earthquake in the epicentral area raises many questions, notably the geometries of sedimentary bodies in depth. In the fluvial plains of the Kupa, Glina and Sava rivers, many lines of sand ejecta and cracks at the surface are subparallel to the riverbanks in convex meanders and would reveal buried sand point bars below a thick layer of silts. In order to highlight the different structures and estimate their mechanical properties, geotechnical and geophysical investigations were carried out at different sites along the Kupa river in the Petrinja epicentral area. This work presents the approach adopted for both the site selection and the study methods. Then, we show some preliminary results as well as the perspectives of further studies on liquefied layers

Comparing Catastrophic Costs: Active vs. Passive Tuberculosis Case Finding in Urban Vietnam

Active case finding (ACF) is a strategy that aims to identify people with tuberculosis (TB) earlier in their disease. This outreach approach may lead to a reduction in catastrophic cost incurrence (costs exceeding 20% of annual household income), a main target of WHO’s End TB Strategy. Our study assessed the socio-economic impact of ACF by comparing patient costs in actively and passively detected people with TB. Longitudinal patient cost surveys were prospectively fielded for people with drug-sensitive pulmonary TB, with 105 detected through ACF and 107 passively detected. Data were collected in four Vietnamese cities between October 2020 and March 2022. ACF reduced pre-treatment (USD 10 vs. 101, p p p = 0.001) and use of coping strategies (28.6% vs. 45.7%, p = 0.004). However, catastrophic cost incurrence was high at 52.8% and did not differ between cohorts. ACF did not significantly decrease indirect costs, the largest contributor to catastrophic costs. ACF reduces costs but cannot sufficiently reduce the risk of catastrophic costs. As income loss is the largest driver of costs during TB treatment, social protection schemes need to be expanded