Sun-induced canopy chlorophyll fluorescence in both the red (FR) and far-red (FFR) regions was estimated across a range of temporal scales and a range of species from different plant functional types ...using high resolution radiance spectra collected on the ground. Field measurements were collected with a state-of-the-art spectrometer setup and standardized methodology. Results showed that different plant species were characterized by different fluorescence magnitude. In general, the highest fluorescence emissions were measured in crops followed by broadleaf and then needleleaf species. Red fluorescence values were generally lower than those measured in the far-red region due to the reabsorption of FR by photosynthetic pigments within the canopy layers. Canopy chlorophyll fluorescence was related to plant photosynthetic capacity, but also varied according to leaf and canopy characteristics, such as leaf chlorophyll concentration and Leaf Area Index (LAI). Results gathered from field measurements were compared to radiative transfer model simulations with the Soil-Canopy Observation of Photochemistry and Energy fluxes (SCOPE) model. Overall, simulation results confirmed a major contribution of leaf chlorophyll concentration and LAI to the fluorescence signal. However, some discrepancies between simulated and experimental data were found in broadleaf species. These discrepancies may be explained by uncertainties in individual species LAI estimation in mixed forests or by the effect of other model parameters and/or model representation errors. This is the first study showing sun-induced fluorescence experimental data on the variations in the two emission regions and providing quantitative information about the absolute magnitude of fluorescence emission from a range of vegetation types.
This study investigates the possibility of monitoring carbon fixation of a terrestrial ecosystem from high spectral resolution field spectroscopy measurements. Canopy radiance spectra were collected ...under clear sky conditions using high resolution spectrometers which made it possible to estimate sun-induced chlorophyll fluorescence at the oxygen absorption band O
2-A located at 760
nm (
F
760) as well as spectral vegetation indices. Spectral observations were collected in a rice field monitored with an eddy covariance (EC) flux tower measuring the net ecosystem exchange (NEE) of the crop.
Estimation of gross ecosystem productivity (GEP) from remotely sensed data was based on the widely used light-use efficiency model (LUE), which states that carbon uptake is a function of the photosynthetically active radiation absorbed by vegetation (APAR) and light-use efficiency (
ɛ) which represents the conversion efficiency of energy to fixed carbon.
Hyperspectral data were used to derive both the APAR and the
ɛ term. Different versions of the LUE model were formalized and tested with EC fluxes during two growing seasons. We started using a LUE model in which
ɛ is held constant and remote sensing data are used to estimate APAR. We then investigated the improvements in GEP modelling provided by the partitioning between photosynthetic (PV) and non-photosynthetic (NPV) components of vegetation in APAR estimation, holding
ɛ constant. The use of spectral indices related to APAR
PV instead of APAR resulted in an improvement in midday GEP estimation of about 50% with respect to the basic LUE model, average root mean square error in cross-validation (RMSE
cv) of the model class from 9.69 to 4.49
μmol CO
2
m
−2
s
−1. Afterwards, we tested the use of the apparent fluorescence yield (Fy
*
760) and the scaled Photochemical Reflectance Index (sPRI) to derive
ɛ. Modelling
ɛ further improved the estimation of GEP up to an RMSE
cv of 3.81
μmol CO
2
m
−2
s
−1 using Fy
*
760 and the MERIS terrestrial chlorophyll index (MTCI) and 3.67
μmol CO
2
m
−2
s
−1 using sPRI and
F
760 to estimate
ɛ and APAR
PV, respectively.
The twin satellites Sentinel-3 (S3A/B) with Ocean and Land Colour Imager (OLCI) sensors, with a spatial resolution of 300 m, and a revisiting time of 1-2 days, and the twin satellites Sentinel-2 ...(S2A/B) with MultiSpectral Instrument (MSI) instrument, with a spatial resolution up to 10 m, offer a special opportunity to monitor at both small and large scale, phytoplankton phenology and variation at small time (OLCI) and at small spatial scale (MSI). The aim of this study was to contribute to further testing on MSI imagery, for retrieving chlorophyll-a (chl-a) concentration, proxy of phytoplankton abundance, in inland waters. Since OLCI has higher revisiting frequency and multiple matchups with MSI, it was also examined as a surrogate for MSI. A common image-processing scheme for both sensors was applied in the two large Italian lakes Garda (oligo-mesotrophic) and Trasimeno (eutrophic). Results showed good performances, both in retrieving atmospherically corrected Remote Sensing Reflectance, and, from this last derived, chl-a concentration maps. Very good accordance was assessed between simultaneous OLCI and MSI derived chl-a maps, both in terms of magnitude, and spatial distribution, despite the fact variations in concentration at small scale were better retrieved by MSI imagery.
Hereditary angioedema (HAE) is characterized clinically by recurrent acute skin swelling, abdominal pain, and potentially life-threatening laryngeal edema. Three forms of HAE have been described. The ...classic forms, HAE types I and II, occur as a consequence of mutations in the C1-inhibitor gene. In contrast to HAE types I and II, HAE type III has been observed exclusively in women, where it appears to be correlated with conditions of high estrogen levels—for example, pregnancy or the use of oral contraceptives. A recent report proposed two missense mutations (c.1032C→A and c.1032C→G) in F12, the gene encoding human coagulation factor XII (FXII, or Hageman factor) as a possible cause of HAE type III. Here, we report the occurrence of the c.1032C→A (p.Thr328Lys) mutation in an HAE type III–affected family of French origin. Investigation of the F12 gene in a large German family did not reveal a coding mutation. Haplotype analysis with use of microsatellite markers is compatible with locus heterogeneity in HAE type III. To shed more light on the pathogenic relevance of the HAE type III–associated p.Thr328Lys mutation, we compared FXII activity and plasma levels in patients carrying the mutation with that of healthy control individuals. Our data strongly suggest that p.Thr328Lys is a gain-of-function mutation that markedly increases FXII amidolytic activity but that does not alter FXII plasma levels. We conclude that enhanced FXII enzymatic plasma activity in female mutation carriers leads to enhanced kinin production, which results in angioedema. Transcription of F12 is positively regulated by estrogens, which may explain why only women are affected with HAE type III. The results of our study represent an important step toward an understanding of the molecular processes involved in HAE type III and provide diagnostic and possibly new therapeutic opportunities.
Flow velocities were measured on the Plator rock glacier in the Central Italian Alps using a correlation image analysis algorithm on orthophotos acquired by drones between the years 2016 and 2020. ...The spatial patterns of surface creep were then compared to the Bulk Creep Factor (BCF) spatial variability to interpret the rock glacier dynamics as a function of material properties and geometry. The rock glacier showed different creep rates in the rooting zone (0.40–0.90 m/y) and in the frontal zone (>4.0 m/y). Close to the rock glacier front, the BCF assumed the highest values, reaching values typical of rock glaciers experiencing destabilisation. Conversely, in the rooting zone the small rates corresponded to lowest BCFs, about five times smaller than in the frontal zone. The Plator rock glacier revealed a substantial advancement from 1981 to 2020 and distinct geomorphological features typical of rock glaciers exhibiting destabilising processes. Given the fast-moving phase, the advancement of both the front line and the front toe of the rock glacier, and the contrasting spatial distribution in the BCFs, the Plator could be considered a destabilised rock glacier.
Lithium-sulfur technology is a strong candidate for the future generation of batteries due to its high specific capacity (1675 mAh g-1), low cost, and environmental impact. In this work, we propose a ...facile and solvent-free microwave synthesis for a composite material based on doped (sulfur and nitrogen) reduced graphene oxide embedded with zinc sulfide nanoparticles (SN-rGO/ZnS) to improve the battery performance. The chemical-physical characterization (XRD, XPS, FESEM, TGA) confirmed the effectiveness of the microwave approach in synthesizing the composite materials and their ability to be loaded with sulfur. The materials were then thoroughly characterized from an electrochemical point of view (cyclic voltammetry, galvanostatic cycling, Tafel plot, electrochemical impedance spectroscopy, and Li2S deposition test); the SN-rGO/ZnS/S8 cathode showed a strong affinity towards polysulfides, thus reducing their loss by diffusion and improving redox kinetics, allowing for faster LiPSs conversion. In terms of performance, the composite-based cathode increased the specific capacity at high rate (1 C) from 517 to 648 mAh g-1. At the same time, more stable behavior was observed at 0.5 C with capacity retention at the 750th cycle, where it was raised from 32.5% to 48.2%, thus confirming the beneficial effect of the heteroatomic doping process and the presence of zinc sulfide nanoparticles.
The aim of this study is to test a series of methods relying on hyperspectral measurements to characterize phytoplankton in clear lake waters. The phytoplankton temporal evolutions were analyzed ...exploiting remote sensed indices and metrics linked to the amount of light reaching the target (EPAR), the chlorophyll-a concentration (Chl-aOC4) and the fluorescence emission proxy. The latter one evaluated by an adapted version of the Fluorescence Line Height algorithm (FFLH). A peculiar trend was observed around the solar noon during the clear sky days. It is characterized by a drop of the FFLH metric and the Chl-aOC4 index. In addition to remote sensed parameters, water samples were also collected and analyzed to characterize the water body and to evaluate the in-situ fluorescence (FF) and absorbed light (FA). The relations between the remote sensed quantities and the in-situ values were employed to develop and test several phytoplankton primary production (PP) models. Promising results were achieved replacing the FA by the EPAR or FFLH in the equation evaluating a PP proxy (R2 > 0.65). This study represents a preliminary outcome supporting the PP monitoring in inland waters by means of remote sensing-based indices and fluorescence metrics.
Student training requires specific laboratories for vaccination practice, which are usually limited, and even professionals' continuing education regularly lacks proper care. Thus, new methodologies, ...concepts, and technologies, such as software-based simulations, are in highly demand.
This work aims to develop a 3D virtual environment to support teaching activities in the vaccination room. The software-based simulation must contribute positively to teaching considering a variable set of scenarios.
We applied the design science research method to guide the work. First, the concepts and opportunities were raised, which we used to build the simulation (ie, the proposed technological artifact). The development was assisted by a specialist, in which we sought to create a vaccination room according to Brazilian standards. The artifact evaluation was achieved in 2 stages: (1) an evaluation to validate the design with experts through the Delphi method; and (2) a field evaluation with nursing students to validate aspects of usability (System Usability Scale SUS) and technology acceptance and use (Unified Theory of Acceptance and Use of Technology version 2).
We built the simulation software using the Unity game engine. An additional module was also developed to create simulation scenarios and view the students' performance reports. The design evaluation showed that the proposed solution is adequate. Students' evaluations confirm good usability (SUS score of 81.4), besides highlighting Performance Expectation as the most positively influential factor of Behavioral Intention. Effort Expectancy is positively affected by younger users. Both evaluation audiences cited the high relevance of the proposed artifact for teaching. Points for improvement are also reported.
The research accomplished its goal of creating a software-based simulation to support teaching scenarios in the vaccination room. The evaluations still reveal desirable improvements and user behavior toward this kind of technological artifact.
Recent data suggest that robotic platform has become the most accessible minimal invasive surgery even for surgeons without previous training in laparoscopy. Laparoscopic partial nephrectomy (LPN) is ...a well-stablished procedure, however, with high level of complexity and long learning curve that limit its use.
To describe safety, efficiency and learning curve of a single surgeon without previous experience in LPN to reach "TRIFECTA" at robot-assisted partial nephrectomy (RAPN).
This is a retrospective study, with prospective data collection of 101 patients submitted to RAPN by a single surgeon. In order to analyze the learning curve, sample was chronologically divided in two phases: first phase: P1: 50 first patients, second phase: P2: 51 subsequent patients. TRIFECTA was defined as: ischemia time lower than 25 minutes, negative surgical margin and absence of severe complications (Clavien >2).
Mean age of patients was 54 years (SD=11.85), median tumor size was 32mm (SD=17) and surgery was performed with zero ischemia time in 33.6% of patients (29.8% at P1 and 40.9% at P2). Demographic data of patients were similar between both groups, except tumor size (P1=27.5mm vs. P2=35.3mm; p=0.02) and body mass index (BMI) (P1=26.6kg/m2 vs. P2=29kg/m2; p=0.03). Rate of bleeding, surgical time, presence of positive margin and peri-operatory surgical complications were similar in both phases. TRIFECTA was higher in P2 in relation to P1 (P1: 58% vs. P2: 87.8%; p=0.002) and median time of hot ischemia was significantly lower at P2 (P1: 17.3 vs. P2: 11.7; p=0.02). At multivariate analysis independent factors related to TRIFECTA included: chronological phase (OR 10.74; 95% IC: 1.63-70.53; p=0.013) and tumor size (OR 0.95; 95% IC: 0.91-0.99; p=0.024).
RAPN seems to be safe and efficient with good functional and oncological results (TRIFECTA) since the beginning. Experience improvement was related to treatment of larger tumors, higher proportion of patients with zero ischemia and higher rate of TRIFECTA.
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