In arid and semi-arid areas, rainfall is often characterized by a strong spatial and temporal variability. These environmental factors, combined with the sparsity of the measurement networks in ...developing countries, constitute real constraints for water resources management. In recent years, several spatial rainfall measurement sources have become available, such as TRMM data (Tropical Rainfall Measurement Mission). In this study, the TRMM 3B42 Version 7 product was evaluated using rain gauges measurements from 19 stations in the Oum-Er-Bia (OER) basin located in the center of Morocco. The relevance of the TRMM product was tested by direct comparison with observations at different time scales (daily, monthly, and annual) between 1998 and 2010. Results show that the satellite product provides poor estimations of rainfall at the daily time scale giving an average Pearson correlation coefficient (r) of 0.2 and average Root Mean Square Error (RMSE) of 10 mm. However, the accuracy of TRMM rainfall is improved when temporally averaged to monthly time scale (r of 0.8 and RMSE of 28 mm) or annual time scale (r of 0.71 and RMSE of 157 mm). Moreover, improved correlation with observed data was obtained for data spatially averaged at the watershed scale. Therefore, at the monthly and annual time scales, TRMM data can be a useful source of rainfall data for water resources monitoring and management in ungauged basins in semi-arid regions.
Residual stress has become more important than ever with the increasing performance requirement of components especially for those applied in safety-critical areas. As the machining process is ...fundamentally correlated with the acquired component properties, it is essential to fully understand the formation mechanism of residual stresses in the cutting process and its influence on the performance of the component. This paper presents results based on numerical and experimental analysis on the effect of tool geometry on thermal-mechanical load and residual stresses in orthogonal machining Inconel718 alloy. The Coupled Eulerian-Lagrangian (CEL) method is used to simulate the effect of tool geometry on temperatures, forces, equivalent plastic strains, and residual stresses. The local normal/tangential stress is introduced to determine the degree of the tensile plastic deformation induced by the tool. It is observed that a negative rake angle and a sharp edge radius tool tend to generate more compressive stress on the machined surface than the ones generated with positive rake angle tools and/or lager edge radius. Besides, an increase in flank wear produces less magnitude of compressive stress in subsurface due to a decreased local normal stress caused by increased flank contact length.
Context.
Interstellar and circumstellar ices are largely composed of frozen water. Therefore, it is important to derive fundamental parameters for H
2
O ice such as absorption and scattering ...opacities, for which accurate complex refractive indexes are needed.
Aims.
The primary goal of the work presented here is to derive ice-grain opacities based on accurate H
2
O ice complex refractive indexes at low temperatures and to assess the impact this has on the derivation of water ice column densities and porosity in space.
Methods.
We used the
optool
code to derive ice-grain scattering and absorption opacity values based on new and previously reported mid-infrared (mid-IR) complex refractive index measurements of H
2
O ice, primarily in its amorphous form, but not exclusively. Next, we used those opacities in the
RADMC-3D
code to run a radiative transfer simulation of a protostellar envelope containing H
2
O ice, which was then used to calculate water ice column densities.
Results.
We found that the real refractive index in the mid-IR of H
2
O ice at 30 K is ~14% lower than previously reported in the literature. This has a direct impact on the ice column densities derived from the simulations of embedded protostars. Additionally, we found that ice porosity plays a significant role in the opacity of icy grains and that the H
2
O libration mode can be used as a diagnostic tool to constrain the porosity level. Finally, the refractive indexes presented here allowed us to estimate a grain size detection limit of 18 μm based on the 3 μm band, whereas the 6 μm band allowed us to trace grain sizes larger than 20 μm.
Conclusions.
Based on radiative transfer simulations using new mid-IR refractive indexes, we conclude that H
2
O ice leads to more absorption of infrared light than previously estimated. This implies that the 3 and 6 μm bands remain detectable in icy grains with sizes larger than 10 μm. Finally, we also propose that the H
2
O ice libration band can be used as a diagnostic tool to constrain the porosity level of the interstellar ice, in addition to the OH dangling bond, which is now routinely used for this purpose.
Nitrogen-bearing complex organic molecules have been commonly detected in the gas phase but not yet in interstellar ices. This has led to the long-standing question of whether these molecules form in ...the gas phase or in ices. The James Webb Space Telescope (JWST) offers the sensitivity, spectral resolution, and wavelength coverage needed to detect them in ices and investigate whether their abundance ratios are similar in gas and ice. We report the first tentative detection of CH3CN, C2H5CN and the simple molecule, N2O, based on the CN-stretch band in interstellar ices toward three (HOPS 153, HOPS 370, and IRAS 20126+4104) out of the five protostellar systems observed as part of the Investigating Protostellar Accretion (IPA) GO program with JWST-NIRSpec. We also provide upper limits for the two other sources with smaller luminosities in the sample. We detect OCN− in the ices of all sources with typical CH3CN/OCN− ratios of around 1. Ice and gas column density ratios of the nitrogen-bearing species with respect to each other are better matched than those with respect to methanol, which are a factor of ~5 larger in the ices than the gas. We attribute the elevated ice column densities with respect to methanol to the difference in snowline locations of nitrogen-bearing molecules and of methanol, biasing the gas-phase observations toward fewer nitrogen-bearing molecules. Moreover, we find tentative evidence of the enhancement of OCN−, CH3CN, and C2H5CN in warmer ices; although, the formation of these molecules likely starts along with methanol in the cold prestellar phase. Future surveys combining NIRSpec and MIRI, and additional laboratory spectroscopic measurements of C2H5CN ice, are necessary for robust detection and conclusions on the formation history of complex cyanides.
Highlights • Cerebral malaria mice showed significant memory impairment. • Infected mice showed reduction of BDNF mRNA expression in the CNS. • TRKB mRNA expression was enhanced in the CNS of ...infected mice. • Inflammatory cytokine levels were increased in the hippocampus of infected mice. • Infected mice showed neurogenesis reduction and increased hippocampal cell death.
The Video Capsule Diagnostic Imaging is a technique for exploring the digestive tract, particularly the small bowel. It is indicated for any unexplained digestive bleeding or as a means of monitoring ...intestinal polyposis or inflammatory diseases. This videocapsule is not digestible, and the risk of its retention, symptomatic or not, is not negligible following an inflammatory, anastomatous or tumoral stenosis. This retention or blockage is defined by the presence of the Video Capsule in the digestive tract at least two weeks after ingestion. Surgical approach is considered effective to retrieve the retained capsule, treat the pathology responsible and prevent acute complications.
We report the case of retention of a video capsule in a young patient with severe anaemia due to inflammatory polyposis of the small bowl, whose removal required surgery to extract the capsule and resect the segment of the small intestine stenosis by the polyps.
•The video Capsule Endoscopy is the most sensitive examination for the detection of inflammatory lesions of the small bowel.•It does not currently allow a biopsy but it is indicated for unexplained or occult digestive bleeding.•Its main limitation is the risk of blockage in a stenosis with or without occlusion.•Surgical approach is considered effective to retrieve the retained capsule, and treat the pathology responsible.
ABSTRACT
The processing of H2O:CO2:CH4 (10:1:1) and H2O:CO2:CH4:NH3 (10:1:1:1) ices at 72 K by oxygen ions was studied in an attempt to simulate the physicochemical effects induced by energetic ions ...on the surface of Enceladus (or similar cold surfaces in the outer Solar System). The experiments were carried out at the Grand Accélérateur National d’Ions Lourds (GANIL) in Caen/France. The samples were irradiated with 15.7-MeV O5+ at the IRRadiation SUD (IRRSUD) beamline and with 108-keV O6+ at the Accélérateurs pour les Recherches avec les Ions de Basses Energies (ARIBE) beamline. The frozen samples were monitored by Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy (4000–650 cm−1, 2.5–15.4 μm, at 1 cm−1 resolution). The identified molecular species formed during irradiation were CO, OCN−, CH3OH, HCN, CN−, H2CO3, HNCO, HCO and CO3. The effective formation cross-sections for the synthesis of new species and the effective molecular destruction cross-sections of the parent species in the experiments with MeV ions were found to be of the order of 10−14–10−13 cm2. For the keV ion experiments, these values were of the order of 10−16–10−15 cm2. The fluence at which the sample reaches chemical equilibrium and the molecular abundances in this region (equilibrium branching ratios) were estimated. These experiments suggest that the chemical inventory on the surface of Enceladus can be influenced by the incidence of charged particles on to the moon’s surface.
Object recognition is a fundamental concept in computer vision. Object detection models have recently played a vital role in various applications, including real-time and safety-critical systems such ...as camera surveillance and self-driving cars. Scientific research has proven that object detection models are prone to adversarial attacks. Although several proposed methods exist throughout the literature, they either target white-box models or specific-task black-box models and do not generalize on other detectors. In this paper, we proposed a new adversarial attack against Blackbox-based object detectors called AT-BOD. The proposed AT-BOD model can fool the single-stage and multi-stage detectors, where we used an optimization algorithm to generate adversarial examples depending only on the detector predictions. AT-BOD model works in two diverse ways, reducing the confidence score and misleading the model to make the wrong decision or hide the object detection models. Our solution achieved a fooling rate of 97% and a false negative increase of 99% on the YOLOv3 detector, and a fooling rate of 61% false-negative increase of 57% on the Faster R-CNN detector. The detection accuracy of YOLOv3 and Faster R-CNN under AT-BOD was dramatically reduced and reached ≤1% and ≤3%, respectively.
The genus Proceratophrys Miranda-Ribeiro, 1920, frogs from the family Odontophrynidae Lynch, currently contains 41 nominal species with poorly resolved phylogenetic relationships (Frost 2019; Mângia ...et al. 2018). Molecular data from 15 and 18 Proceratophrys species support the monophyletic hypothesis of the genus (Teixeira-Jr et al. 2012; Dias et al. 2013; respectively) but do not fully resolve the phylogenetic relationship among the species. Currently, there are advertisement call parameters provided for 31 species of Proceratophrys in the literature (Ferreira et al. 2016; Andrade et al. 2018; Mângia et al. 2018; Nascimento et al. 2019). The Proceratophrys advertisement call is composed of pulsed notes, amplitude modulation, short to medium duration calls (0.05-4 s) and only one note in almost all species (see Nascimento et al. 2019 for details). Considering the importance of bioacoustics for taxonomy (Köhler et al. 2017), further descriptions of advertisement calls for the genus could also improve our understanding of the species' relationships.
Solid pseudopapillary tumor of the pancreas (SPTP) is a rare tumor of the exocrine pancreas, with undetermined etiopathogeny, which most often affects young women. The clinical and physical signs are ...non-specific and despite the progress of complementary examinations, Confirmation is usually anatomopathological. Surgical resection is the only curative treatment.
We report the case of a 17-year-old girl, consulted for a left hypochondrium mass which imaging concluded to be a corporal-caudal tumor mass of the pancreas for which a complete surgical excision was performed and whose anatomopathological study confirmed a pseudo-papillary and solid tumor of the pancreas. The positive diagnosis of SPTP remains difficult and is usually made on pathological analysis with immunohistochemical study.
Solid pseudopapillary tumor of the pancreas is a rare anatomic-clinical entity, first described by Frantz in 1959. The clinical manifestations of SPTP are not specific. Biologically, no signs are predictive of SPTP and imaging usually shows a well encapsulated mass with both solid and cystic components. The curative treatment of SPTP is exclusively surgical and consists of a complete removal of the tumor with its capsule because of its degenerative potential SPTP has a good prognosis with a recurrence rate of 10–15% and 95% survival at 5 years.
Solid pseudopapillary tumor of the pancreas is a rare tumor of the exocrine pancreas. Its evolution is slow. Preoperative diagnosis remains difficult despite the progress of complementary examinations. Surgical resection is the only curative treatment. Its prognosis remains excellent.
•Solid pseudopapillary tumor of the pancreas is an extremely rare epithelial tumor.•It is a tumor with a low malignant potential and its etiopathogeny is still uncertain.•An immunohistochemical study is essential for diagnosis, and several specific markers have been identified.•The curative treatment of pancreatic pseudopapillary solid tumor is exclusively surgical.
PDF
