Search results for "Linear relation"
showing 10 items of 35 documents
Radiance-based NIRv as a proxy for GPP of corn and soybean
2020
Abstract Substantial uncertainty exists in daily and sub-daily gross primary production (GPP) estimation, which dampens accurate monitoring of the global carbon cycle. Here we find that near-infrared radiance of vegetation (NIRv,Rad), defined as the product of observed NIR radiance and normalized difference vegetation index, can accurately estimate corn and soybean GPP at daily and half-hourly time scales, benchmarked with multi-year tower-based GPP at three sites with different environmental and irrigation conditions. Overall, NIRv,Rad explains 84% and 78% variations of half-hourly GPP for corn and soybean, respectively, outperforming NIR reflectance of vegetation (NIRv,Ref), enhanced vege…
Patterns Comparison Between Gome-2 Sun-Induced Fluorescence and Msg Gross Primary Production
2018
A comparison between maximum monthly MSG gross primary production (GPP) estimates with the sun-induced chlorophyll fluorescence (SIF) product from the Global Ozone Monitoring Experiment-2 (GOME-2) over Europe and Africa is presented as an indirect validation of MSG GPP estimates. The maximum daily GPP value for each month is derived from daily MSG GPP, which takes full advantage of the SEVIRI/MSG products from the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) delivered by the Satellite Application Facility for Land Surface Analysis (LSA SAF). A linear relationship found between both products over savanna, grasslands and forests at high latitudes evidence…
Antimicrobial Chemotherapy has a Linear Relationship to the Proportion of Gram-Negative Isolates from Pediatric Burn Wounds.
2018
Wound infection in burns is a relevant cause of morbidity and mortality in children. We aimed to determine the relationship between antibacterial chemotherapy and Gram-negative burn wound colonization and infection. All children admitted to the pediatric intensive care unit for burn trauma from June 1, 2005 to January 31, 2013 were included. We obtained 141 wound samples, of which 88 (65.7%) showed growth of Gram-positive bacteria. Treatment with antimicrobial chemotherapy was necessary in 23 (31.1%) patients. The proportion of Gram-negative isolates seems to increase linear from 12.5% (95% confidence interval (CI): 4.4%-28.7%) without antibacterial chemotherapy to 36.8% (95% CI: 25.5%-49.6…
Dependence of plasma pH on oxygen saturation
1969
Abstract The influence of haemoglobin oxygenation on the pH value of the blood plasma of healthy adolescents was investigated at 38°C by varying the parameters CO2 pressure, Hb concentration and buffer bases. A total of 5000 measurements gave the following results: 1. 1. The pHs difference between oxygenated and deoxygenated blood increases with diminishing CO2 pressure and with increasing Hb concentration. There is a linear relation between the pHs changes and the O2 saturation of the haemoglobin. 2. 2. Quantitatively these relationships can be expressed by the following equation: δpHs = (8 − pH ox − log 0.03 Pco 2 ) · [Hb] 225 · (100 − So 2 100 where ΔpHs is the pHs difference between par…
A radiometric and petrographic approach to risk assessment at Alte Madonie Mounts region (Sicily, Italy)
2013
The main goal of this work was to assess the radiological hazard at Alte Madonie Mounts region (north-central Sicily, Italy) in response to rumours of an increase in the incidence of cancer in this area. A correlation between the natural radionuclide contents and the petrographic features of the soil and rock samples was also evaluated. A total of 41 samples of selected soils and rocks were collected, powdered, dried and sealed in 'Marinelli' beakers for 20 d prior to measurement to ensure that a radioactive equilibrium between (226)Ra and (214)Bi had been reached. A gamma-ray spectrometer was used to quantify the radioactivity concentrations. To determine (238)U and (232)Th activities, the…
Comparison between direct and predicted maximal oxygen uptake measurement during cycling.
2013
Predicted maximal oxygen uptake (VO2max) measurements are based on the assumption of linear relationship between heart rate or power output and oxygen consumption during various intensities. To develop more reliable predicted test for soldiers, the purpose of the present study was to compare the results of direct measurements of VO2max to respective predicted values in cycling (military fitness test). The predicted mean (+/- SD) peak oxygen uptake (VO2peak) value was 45.2 +/- 7.7 mL kg(-1) min(-1) during first week, whereas the respective direct value was 44.8 +/- 8.5 mL kg(-1) min(-1). During the ninth week, the predicted and measured mean (+/-SD) VO2max values were 47.4 +/- 6.7 mL kg(-1) …
Feasibility, reproducibility, and reliability for the T*2 iron evaluation at 3 T in comparison with 1.5 T
2012
This study aimed to determine the feasibility, reproducibility, and reliability of the multiecho T * 2 Magnetic resonance imaging technique at 3 T for myocardial and liver iron burden quantification and the relationship between T * 2 values at 3 and 1.5 T. Thirty-eight transfusion-dependent patients and 20 healthy subjects were studied. Cardiac segmental and global T * 2 values were calculated after developing a correction map to compensate the artifactual T * 2 variations. The hepatic T * 2 value was determined over a region of interest. The intraoperator and interoperator reproducibility for T * 2 measurements at 3 T was good. A linear relationship was found between patients' R (1000/T * …
Gelchromatographie. 8. Mitt.: Vernetzte copolymere des vinylacetats
1969
Die Eigenschaften von vernetzten Copolymeren des Vinylacetats wurden in Abhangigkeit von den Herstellungsbedingungen gepruft. Als Vernetzungsmittel dienten Divinyladipat und Butandiol-(1.4)-divinylather. Mit homogen-vernetzten Gelen konnen Ausschlusmolekulargewichte bis etwa 4000 erzielt werden: zwischen dem spezifischen Gelbettvolumen und dem Ausschlusmolekulargewicht besteht eine lineare Beziehung. Die heterogen-vernetzende Copolymerisation des Vinylacetats in Gegenwart verschiedener inerter Verdunnungsmittel fuhrt zu Gelen mit Ausschlusmolekulargewichten uber 106. Die vernetzten Copolymeren wurden durch ihre scheinbare Dichte, durch die Aufnahme von Losungs- und Fallungsmitteln, durch di…
A more reliable relation between Angström and Linke atmospheric turbidity parameters
1989
Abstract This work analyses the correlation between Angstrom and Linke atmospheric turbidity parameters (β and T ) which are commonly used in studies about the atmosphere's behaviour since they efficaciously monitor a point turbidity state and model the aerosol attenuation of solar radiation. Starting from the usual linear relation β = a + bT , a more reliable one is here derived by hourly data of three coastal locations with typical Mediterranean meteoclimatic characteristics, for values of the experimental ratios of diffuse and global solar radiation ⩽0.3. The expression found notably differs from the starting one as shown by the time variable.
Ratio of UV to global broad band irradiation in Valencia, Spain
1999
This paper presents the results of an analysis of 6 years of measurements of UV and broad band irradiation values in Valencia, Spain. Hourly and daily integrated UV irradiance, ITUV, measured by a TUVR Eppley radiometer, and global irradiance IT from a Kipp-Zonen CM-11 pyranometer, were highly correlated, with ITUV/IT percentages varying from 2.9% to 3.5% for hourly values and from 2.9% to 3.4% for daily values. If a general linear relation ITUV=mIT is considered, the correlation coefficient r is always greater than 0.96 for hourly values and 0.91 for daily values. However, the relation between ITUV/IT and the clearness index kT is poorly correlated, although improved results, with less dep…