6 research outputs found

    High-Resolution SMAP-Derived Root-Zone Soil Moisture Using an Exponential Filter Model Calibrated per Land Cover Type

    Get PDF
    Root-zone soil moisture (RZSM) plays a key role for most water and energy budgets, as it is particularly relevant in controlling plant transpiration and hydraulic redistribution. RZSM data is needed for a variety of different applications, such as forecasting crop yields, improving flood predictions and monitoring agricultural drought, among others. Remote sensing provides surface soil moisture (SSM) retrievals, whose key advantage is the large spatial coverage on a systematic basis. This study tests a simple method to retrieve RZSM estimates from high-resolution SSM derived from SMAP (Soil Moisture Active Passive). A recursive exponential filter using a time constant τ is calibrated per land cover type, which uses as an intermediate step a long-term ISBA-DIF (Interaction Soil Biosphere Atmosphere—Diffusion scheme) dataset over an area located in Catalonia, NE of Spain. The τ values thus obtained are then used as an input to the same recursive exponential filter, to derive 1 km resolution RZSM estimates from 1 km SMAP SSM, which are obtained from the original data by downscaling to a 1 km resolution, through the DISPATCH (DISaggregation based on a Physical and Theoretical scale CHange) methodology. The results are then validated with scaled in situ observations at different depths, over two different areas, one representative of rainfed crops, and the other of irrigated crops. In general, the estimates agree well with the observations over the rainfed crops, especially at a 10 cm and 25 cm depth. Nash–Sutcliffe (NS) scores ranging between 0.33 and 0.58, and between 0.37 and 0.56 have been found, respectively. Correlation coefficients for these depths are high, between 0.76 and 0.91 (10 cm), and between 0.71 and 0.90 (25 cm). For the irrigated sites, results are poorer (partly due to the extremely high heterogeneity present), with NS scores ranging between −2.57 and 0.16, and correlations ranging between −0.56 and 0.48 at 25 cm. Given the strong correlations and NS scores found in the surface, the sensitivity of the filter to different τ values was investigated. For the rainfed site, it was found, as expected, with increasing τ, increasing NS and correlations with the deeper layers, suggesting a better coupling. Nevertheless, a strong correlation with the surface (5 cm) or shallower depths (10 cm) observed over certain sites indicates a certain lack of skill of the filter to represent processes which occur at lower levels in the SM column. All in all, a calibration accounting for the vegetation was shown to be an adequate methodology in applying the recursive exponential filter to derive the RZSM estimates over large areas. Nevertheless, the relative shallow surface at which the estimates correlate in some cases seem to indicate that an effect of evapotranspiration in the profile is not well captured by the filter.This research was funded by the Torrres Quevedo program of the Spanish Science Ministry, MICINN (grant number PTQ-16-08766)

    Smos based high resolution soil moisture estimates for desert locust preventive management

    No full text
    International audienceThis paper presents the the first attempt to include soil moisture information from remote sensing in the tools available to desert locust managers. The soil moisture requirements were first assessed with the users. The main objectives of this paper are: i) to describe and validate the algorithms used to produce a soil moisture dataset at 1 km resolution relevant to desert locust management based on DisPATCh methodology applied to SMOS and ii) the development of an innovative approach to derive high (100 m) resolution soil moisture products from Sentinel-1 in synergy with SMOS data. For the purpose of soil moisture validation, 4 soil moisture stations where installed in desert areas (one in each user country). The soil moisture 1km product was thoroughly validated and its accuracy is amongst the best available soil moisture products. Current comparison with in-situ soil moisture stations shows good values of correlation (R > 0.7) and low RMSE (below 0.04 m(3) m(-3)). The low number of acquisitions on wet dates has limited the development of the soil moisture 100m product over the Users Areas. The Soil Moisture product at 1km will be integrated into the national and global Desert Locust early warning systems in national locust centres and at DLIS-FAO, respectively

    Cleft Palate and Aortic Dilatation as Clues for Loeys-Dietz Syndrome

    Get PDF
    Loeys-Dietz syndrome (LDS) is a rare autosomal-dominant disorder of the connective tissue with some typical vascular findings, skeletal manifestations, craniofacial features, and cutaneous findings with a wide phenotypic spectrum. Six different genes are involved in LDS and the diagnosis is based on the identification of a heterozygous pathogenic variant in TGFBR1, TGFBR2, SMAD3, TGFB2, TGFB3, or SMAD2 in children with suggestive findings. These genes distinguish LDS into six classes (LDS1-LDS6, respectively). Delay in diagnosis of Loeys-Dietz syndrome may be associated with an adverse prognosis due to a very high augmented risk of early complications such as aortic or vascular rupture. The present report describes a case of an early diagnosis of LDS in a neonate with cleft soft palate and aortic root dilatation

    Is acidemia at birth a risk factor for functional gastrointestinal disorders?

    No full text
    Functional gastrointestinal disorders (FGIDs) are common in early childhood. It has been demonstrated that neonatal acidemia at delivery can lead to significant neonatal morbidity. The primary aim of this study was to evaluate the relationship between acidemia at birth and the development of FGIDs, as regurgitation, colic, and constipation, in term infants. Term newborns born at the Foggia University Hospital, Italy during the year 2020 were included in the study. As per routine clinical practice, a cord blood gas analysis on a blood sample drawn from the umbilical artery (UA) of each infant immediately after birth was performed, and Apgar score was recorded. One year after birth, each infant's parents were interviewed through a phone call to investigate development of FGIDs, feeding practices, and morbidities. During the study period, 1574 term newborns met the inclusion criteria. The prevalence of infantile colic, regurgitation, and constipation was higher in infants with low UA pH (colic 51.5% vs. 25.4%, p <0.001; regurgitation 30.6% vs. 15.2%, p <0.001; constipation 24.6% vs. 16.0%, p = 0.015), with infants having moderate-severe acidemia facing the highest risk for all the examined FGIDs. In binary logistic regression analyses, UA pH and perinatal antibiotic exposure proved to be independently associated with the later diagnosis of each FGID.Conclusion: Newborns with acidemia at birth appear to face a higher risk of FGIDs in infancy. Avoiding low cord blood pH should continue to be the goal for obstetricians, while enhanced long-term surveillance for infants who experienced birth acidemia should be required

    Idiopathic neonatal hemoperitoneum presented as scrotal hematoma: it’s a diagnostic challenge?

    No full text
    Background: Idiopathic hemoperitoneum in the newborn is an entity very rarely encountered in clinical practice. Case presentation: A case of scrotal hemorrhage (SH) associated with intrabdominal hemorrhaging and acute anemia is presented. Indications for early surgery included a massive scrotal hematoma, rapid onset of severe anemia, and unknown etiology. Conclusion: Clinical and diagnostic approaches in a case of neonatal scrotal hematoma should be given careful consideration as abdominal in origin, and a pre-operative computed tomography (CT) scan or magnetic resonance image (MRI) in addition to an abdominal/scrotal ultrasound should be added as part of the diagnostic work-up

    Midgut volvulus and meconium peritonitis induced non-immune hydrops

    Get PDF
    Meconium peritonitis (MP) is a rare cause of nonimmune hydrops and only few of those cases have been reported in literature. Here is to report on a case of FH secondary to perforated midgut volvulus and MP with special interest in the discussion of pathophysiology and clinical strategies. We report on a preterm male neonate diagnosed with FH at 29th week of gestational age (WGA) and EXIT at 30 WGA. In addition, he presented with abdominal mass, respiratory distress syndrome and hypoglycemia. Emergent endotracheal intubation and mechanical ventilation rescued the baby. All maternal and infant viral panel, Toxoplasmosis, Sars-Covid 2 and indirect/direct coombs tests were negative. . At laparotomy, we found a midgut volvulus interesting nearly all the jejunum but sparing the ileum which appeared hypoplastic. One of intestinal loop was completely perforated with diffuse MP. Distal to the first jejunal loop, the jejunum appeared necrotic and then resected with bowel exteriorization (terminal jejunostomy and ileostomy). The postoperative course was complicated by worsening of respiratory distress, acute tubular necrosis and renal failure unresponsive to medical therapy and fatal outcome. In conclusion, we believe that hydrops secondary to midgut volvulus and meconium peritonitis has its own pathophysiological and clinical characteristics that make this disease at high risk of unfavourable outcome when compared with prenatal cases of midgut and/or meconium peritonitis without hydrops
    corecore