Reflectance Values Research Articles

Analyzing GOES-R ABI BRDF-adjusted EVI2 time series by comparing with VIIRS observations over the CONUS

The Advanced Baseline Imager (ABI) instruments onboard the Geostationary Operational Environmental Satellite-R series (GOES-R) provide new opportunities to expand their applications in global terrestrial ecology and environmental sciences. It offers a 5–15 min temporal resolution and 0.5–1 km spatial resolution that greatly benefit those environmental applications where spatial resolution can be compromised in favor of more frequent imagery. However, ABI captures reflected radiation at varying sun positions throughout the day, causing significant diurnal variations. The varying off-nadir view across ABI full disk presents further challenges for generating comparable and consistent vegetation observations, such as the two-band Enhanced Vegetation Index (EVI2). To address these challenges, three Bidirectional Reflectance Distribution Function (BRDF) models (RossThick-LiSparse-Reciprocal (RTLSR), Walthall, and Tian models) are examined to generate high-quality BRDF-adjusted EVI2 based on GeoNEX GOES-16 ABI surface reflectance. The ABI BRDF retrievals are then systematically compared to the corresponding VIIRS (Visible Infrared Imaging Radiometer Suite) Nadir BRDF-Adjusted Reflectance (NBAR) products (VNP43 V001) retrieved from RTLSR model. The viewing geometry effects are further analyzed over various land cover types using time series analysis, Pearson Correlation Coefficients (PCC), and Relative Difference (RD) between ABI and VIIRS high-quality time series inversions. The results indicate that the RTLSR model fits well the diurnal ABI observed reflectance and EVI2 values (even for the hot-spot phenomena), and outperforms the Walthall and Tian models for generating ABI high-quality BRDF retrievals with consistently low Root Mean Square Error (RMSE<0.02) and Weight of Determination (WoD < 0.5) across the CONUS. The annual proportion of ABI high-quality BRDF retrievals with a 3-day moving window using the RTLSR model is spatially and statistically comparable to that of VIIRS NBAR with a 16-day retrieval period. Compared to the time series of high-quality VIIRS NBAR EVI2, the BRDF adjusted ABI EVI2 time series still show considerable impacts of view zenith angles over evergreen forest, shrubland, and savanna pixels. However, such impacts are not significant over spatially homogeneous pixels such as cropland and deciduous forests. These results emphasize the need for BRDF correction when considering the impact of off-nadir observations from geostationary satellites on vegetation monitoring. They also demonstrate the advantages of geostationary satellites in capturing rapid changes in greenness trajectories.

The Dependence of the Child as a Value for Reflection on Peace in Light of the Concept of the Pedagogical Relationship—Inspired by the Thought of Max Van Manen and Lennart Vriens

Problematyka podjęta w przedstawionej pracy jest ściśle związana z rozwojem idei relacji pedagogicznej, zajmującej szczególnie ważne miejsce w zainteresowaniach badawczych współczesnych przedstawicieli pedagogiki fenomenologicznej na świecie takich jak Max van Manen, Tone Saevi czy Carina Henricsson. Przywołani badacze w szczególnie istotny sposób inspirują się tradycją badawczą tzw. Szkoły w Utrechcie oraz koncepcją „phenomenology of practice”, którą rozwinął uczeń Martinusa Langevelda, Max van Manen. Łączy ich wpływ Emmanuela Levinasa, a rozwijana przez nich koncepcja relacji pedagogicznej w centrum swojej etycznej perspektywy stawiają zatem zależność i kruchość dziecka oraz odpowiedzialność dorosłego. Problematyka heteronomii w relacji pedagogicznej odsłania swoje ogromne znaczenie dla rozwijanej w perspektywie fenomenologicznej i egzystencjalnej pedagogicznej problematyki pokoju. Druga część artykułu koncentruje się na kilku inspiracjach płynących z badań Lennarta Vriensa, który prowadził badania nad żywym doświadczeniem dziecka w odniesieniu do wychowania dla pokoju&#x0D; Wyniki przeprowadzonej analizy wyraźnie wskazują na ogromną potrzebę podejmowania dalszej refleksji nad tym czym dla dziecka jest doświadczenie pokoju i jakiej wiedzy etyczno - pedagogicznej naprawdę potrzebujemy, by budować pokój. Każdy z nas indywidualnie jako osoba - i jako wspólnota.

Maceral composition, coal quality and depositional environments of the middle Permian Ukhaakhudag coal deposit, South Mongolia

The Ukhaakhudag coal deposit is located c. 560 km SSE of the city of Ulaanbaatar in the northeastern sector the South Gobi Basin. The coal-bearing strata is part of the middle Permian Tavantolgoi Formation. This study aims to determine the coal petrographic composition and depositional environments of five coal seams in the lower part of the deposit based on petrographic and chemical analyses of 106 composite samples. Vitrinite ranges from 12 to 64 vol.%, and inertinite varies between 9 and 68 vol.%. Liptinite ranges from 1 to 7 vol.%. Microlithotype analyses indicate that coals are primarily vitrinertite, few coals are classified as trimaceralic microlithotypes duroclarite and clarodurite. The inorganic fraction in the studied coals is mainly composed of clay, small amounts of silica, carbonate, and pyrite minerals. The vitrinite random reflectance values of the samples vary between 0.93-1.16 %. Volatile matter content varies from 26.10 to 41.48 wt.% (dry ash free basis). Ash, moisture, and sulfur contents vary between 11.20-44.76 wt.%, 1.63-6.03 wt.% and 0.49-1.67 wt.%, (air dried basis) respectively. Based on random vitrinite reflectance values and volatile matter content, the studied coals are classified as coking (Ch4), fat (Ch5), 1/3 coking (Ch6), gas fat (Ch7) based on the Mongolian system and medium to high volatile bituminous coal when using the ASTM system. The Gelification Index and Tissue Preservation Index of the studied samples suggest most seams accumulated in wet forest swamps with a high tree density. The Middle Permian peats from this location accumulated in mostly alternate oxic and anoxic mire conditions. The climate was drier during the peat accumulation of Seam 0, but it became warmer, and humidity increased starting from Seam 3 accumulation.

A tectono-thermal perspective on the petroleum generation, accumulation and preservation in the southern Ordos Basin, North China

The southern Ordos Basin has excellent petroleum exploration prospects. However, the tectono-thermal history and the controls on petroleum generation, accumulation and preservation conditions in southern basin are unclear. In this study, we analyzed the present geothermal field, paleo-geothermal gradient, maturity of the hydrocarbon source rocks, uplift and cooling process and tectono-thermal evolution history. In the study area, for the Ordovician, Permain and the Triassic strata, the present temperature is low (30−70 °C) in the southeastern area but high (80−140 °C) in the northwestern area. The paleo-geothermal gradient varied from 24 °C/km to 30 °C/km with a heat flow of 58–69 mW/m2 (i.e., a medium-temperature basin). The paleo-temperatures are higher than the present temperatures and the maximum paleo-temperatures controlled the thermal maturity of the source rocks. The vitrinite reflectance (Ro) values of the Triassic strata are >0.7% and the thermal maturity reached the middle-mature oil generation stage. The Ro values of the Permian-Ordovician strata are >1.8% and the thermal maturity reached the over-mature gas generation stage. The southern Ordos Basin has experienced the multiple tectonic events at the Late Ordovician Caledonian (452 Ma), Late Triassic (215 Ma), Late Jurassic (165−160 Ma), End-Early Cretaceous (110−100 Ma) and Cenozoic (since 40 Ma). A large-scale tectono-thermal event occurred at the End-Early Cretaceous (110−100 Ma), which was controlled by lithospheric extension, destruction and thinning. This event led to the highest paleo-temperatures and thermal maturities and coeval with the peak period of petroleum generation and accumulation. The southern Ordos Basin has undergone rapid and large-scale uplift since the Late Cretaceous due to expansion of the northeastern margin of the Tibetan Plateau, uplift of the Qinling orogenic belt and thrust faulting in the Liupanshan tectonic belt. The southern Ordos Basin experienced tectonic overprinting that was strong in the south and weak in the north. The strongest overprinting occurred in the southwestern part of the basin. The large-scale uplift, denudation and faulting led to oil and gas loss from reservoirs. The petroleum generation, accumulation and preservation in the southern Ordos Basin were affected by deep lithospheric structures and the tectono-thermal evolution. This work provides a novel tectono-thermal perspective on the petroleum generation, accumulation and preservation condition of the southern Ordos Basin.

Fossil charcoal from the Upper Triassic Karamay Formation in the Junggar Basin, NW China, and its geological implications

Fossil charcoal can provide important evidence for understanding the ancient forest fires and predicting changes in vegetation, paleoclimate and paleoenvironment throughout geological history. In this research, a systematic study was conducted on fossil charcoal from the Upper Triassic Karamay Formation in the Junggar Basin, NW China. The charred wood is secondary xylem, pycnoxylic and homoxyleous, composed of tracheids and parenchymatous rays. Based on their anatomical features, the charcoal fossils are identified as Protophyllocladoxylon sp. The presence of well-preserved macroscopic charcoal fossils, along with carbonized leaves, suggests that these fossils were formed as a result of local surface fires. Based on the analysis of the mean random reflectance (Romean) values of charcoal from the Karamay Formation, the estimated temperature range for the production of the charcoal is between 407.49 °C and 369.17 °C. This temperature range aligns with the typical temperatures associated with surface fires, indicating that the fires in this region during the Late Triassic were of low intensity and occurred under relatively low temperatures. The presence of fossil charcoal in Junggar Basin suggests that the paleoatmospheric oxygen level in northwest China during Late Triassic was above 13% or 15%, which is the minimum required for sustained burning of natural wildfires. This finding is in accordance with the paleoatmospheric oxygen concentration models on the basis of variations in inertinite content and Phanerozoic wildfire history combined with the phosphorus cycle. The abundant presence of fossil charcoal herein suggests a humid and warm climate with intermittent droughts in the Late Triassic Junggar Basin.

Uncertainty analysis of IceCube instrument to enhance accuracy of specific surface area measurements

The specific surface area (SSA) is a measure of the snow microstructure and can be determined using an instrument called IceCube. IceCube measures the reflectance from surface of a snow sample with a 1310 nm infrared laser. In this study, the uncertainties associated with IceCube measurements of SSA were analyzed in two locations: Sodankylä, Finland and Queen Maud Land, Antarctica. The study tests the repeatability of the measurements by measuring several samples from the same height of a homogenous snowpack. Additionally, snow samples were rotated to find minimum and maximum reflectance values to test the uncertainty related to the direction of the sample under the laser. The study also observed the uncertainty related to potential melting of the sample in warm conditions due to slow measurement process. The study resulted that the highest uncertainty is related to the sampling process. Overall, this study provides insights into the uncertainties associated with IceCube measurements of SSA, which will improve the precision and reliability of future measurements.

Comparison of Commercial Reflectometers for Solar Mirrors

The important in-field characterization of solar mirror reflectance can be performed by a variety of commercial portable reflectometers. In this study the most common commercially available reflectometers are evaluated in a campaign comparing different reflector materials, covering a wide range of realistic reflectance and specularity values. Where possible, measurements are compared to reference values measured with laboratory equipment. In general, good agreement between measurements is detected for highly specular mirrors (average deviation 0.005±0.004) and methods for improvement are proposed when deviations are detected. Important differences between measurements are found for less specular reflectors, which are caused by the disparity of the measurement parameters of the devices. These differences confirm that detailed knowledge about the device characteristics is important, to be able to correctly interpret and utilize gained results, especially for soiled and degraded mirrors.

Production of monoclonal antibody against tylosin and tilmicosin with homogeneous cross-reactivity and its application in lateral flow immunoassay.

To avoid false negative results due to the low cross-reactivity rate (CR) in rapid immunoassay, a group-specific antibody with homogeneous CR toward target compounds is needed for accuracy. In this study, tylosin (TYL) and tilmicosin (TM) were selected as model molecules. Firstly, two-dimensional similarity, electrostatic potential energy, spatial conformation and charge distribution of the haptens TYL-CMO, TYL-6-ACA, TYL-4-APA, TYL-CHO and DES-CMO and target compounds of TYL and TM were obtained using Gaussian 09W and Discovery Studio. The optimal hapten was DES-CMO because it is the most similar to TYL and TM. Subsequently, the mAb 14D5 cell line was obtained with IC50 values of 1.59 and 1.72ng/mL for TYL and TM, respectively, and a CR of 92.44%. Finally, amorphous carbon nanoparticles (ACNPs) were conjugated with mAb 14D5 to develop an accurate lateral flow immunoassay (LFA) for detection of TYL and TM by the reflectance value under natural light. The recoveries of TYL and TM ranged from 77.18 to 112.04% with coefficient of variation < 13.43%. The cut-off value in milk samples was 8ng/mL, and the limits of detection were 11.44, 15.96, 22.29 and 25.53μg/kg for chicken muscle, bovine muscle, porcine muscle and porcine liver samples, respectively, and the results being consistent with HPLC-UV. The results suggest that the developed LFA is accurate and potentially useful for on-site screening of TYL and TM in milk and animal tissue samples.

Impact of Soiling Physicochemistry on Mirrors With CSP Applications at the Plataforma Solar Del Desierto De Atacama, Chile

The context of global economic instability and armed conflicts has caused fossil fuels to reach unprecedented levels. In this sense, Concentrating Solar Power (CSP) technology has proven to be an excellent option to diversify the energy matrix dependent on fossil fuels, especially in places where there is a good quality solar resource, such as desert areas. These good qualities can be overshadowed by local phenomena such as soiling that can affect the viability of a project. In this paper, the effect of soiling on CSP mirrors installed in a cold desert climate in the Atacama Desert, Chile, is presented. During the 202 days (continuous) of outdoor exposure, atmospheric parameters such as humidity and temperature, as well as reflectance were evaluated daily. At the end of the experiment, the chemical composition of the material deposited on the mirror surface was analyzed by scanning electron microscopy (SEM) and elemental analysis (EDX). The characterization of the material detected the presence of Gypsum (soluble salt), which was shown to have the ability to cement the deposited material. The atmospheric parameters showed that the relative humidity at the site can exceed 60%, sufficient values to solubilize the Gypsum, producing the cementation process. The reflectance values showed that the effect of the cemented material, for 202 days of exposure, can reach a 47% loss of its reflective capacity. This means that the longer the exposure time, the greater the effect of the cementation and the more energy will be needed to clean the mirrors.

First-principles investigation of structural, electronic, and optical properties of cubic halide perovskite RbSrI3

In this article, the structural, electronic, and optical properties of lead-free cubic halide perovskite RbSrI3 are investigated by the first principles method that employs the density functional theory (DFT). This study implements the full potential linearized augmented plane wave (FP-LAPW) method with the generalized gradient approximation of Perdew-Burke-Ernzerhof (PBE-GGA) as the exchange-correlation potential. The structural stability of the compound is calculated using the Murnaghan equation of state, and the band structure calculations show the presence of a wide indirect bandgap of 3.32 eV. The optical response of the compound over the energy spectrum of 0–12 eV is studied and the compound exhibits good reflectance of 30.73 % at 7.66 eV and absorption of 112.45 × 104 cm−1 at 11.74 eV in the ultraviolet region. The values of reflectivity R(ω) and absorption coefficient α(ω) indicate that the compound shows potential in the fabrication of UV-related optoelectronic devices.

First-principles calculations to investigate the physical properties of lead-free double perovskites Cs2AgXCl6 (X=P, Co, As, Cd) for optoelectronic applications

In this work, we have been systematically studied the structural, electronic, optical, mechanical, and thermodynamic properties of double perovskite Cs2AgXCl6 (X= P, Co, As, Cd) by adopting first-principles calculations based on density functional theory (DFT). We found that the determined lattice parameters are in good agreement with the previously reported study, which are 7.518558 Å, 7.491051 Å, 7.370192 Å, and 7.517199 Å for Cs2AgAsCl6, Cs2AgCdCl6, Cs2AgCoCl6, and Cs2AgPCl6, respectively. The negative result of formation energy (ΔHf) indicates that these compounds are thermodynamically stable and can be experimentally synthesized. The electronic energy band structure indicates that Cs2AgXCl6 (X=P, Co, As, Cd) compounds are semiconductor behavior with the band gap (Eg) of 1.047 eV, 1.085 eV, 1.205 eV, and 2.074 eV for Cs2AgPCl6, Cs2AgCoCl6, Cs2AgAsCl6, and Cs2AgCdCl6, respectively. Electronic properties suggest that carrier transport is enhanced in Cs2AgXCl6 (X=P, Co, As, Cd) because of holes and electrons' small effective mass. Furthermore, optical properties suggest that these compounds have high absorption coefficients and low reflectivity values in the visible region. The structural and thermodynamic stability, the obtained energy band gap, tunable optical properties, and interesting thermodynamic properties indicate that Cs2AgXCl6 (X=P, Co, As, Cd) is a potential candidate in photovoltaic and optoelectronic applications.

Integrated 3D geological analysis of hydrocarbon maturation and migration in rift basins: Insights from the Niger Chad Basin

This study presents a comprehensive analysis of hydrocarbon maturation and migration in rift basins, with a particular focus on the Niger Chad Basin. The research employs advanced geological techniques, including 3D modelling, to provide essential insights. The use of 3D modelling techniques enhances the reliability of source rock data by accurately predicting vitrinite reflectance (Ro) and temperature values. This validation highlights the crucial importance of robust source rock characterization in hydrocarbon exploration. The role of fault systems in hydrocarbon drainage and accumulation is a prominent finding, with large-scale intra-basinal faults directing basin dynamics effectively. The timing of hydrocarbon generation relative to seal formation emerges as a pivotal factor affecting oil trapping, emphasizing the temporal aspects of petroleum system elements. The Madama Sandstone Formation plays a dual role as a reservoir rock and conduit for oil transmission, underscoring its significance in the hydrocarbon system. Its extensive lateral spread facilitates hydrocarbon drainage, revealing valuable insights into rift basin dynamics. In the future, further research should delve into the intricate interactions within rift basin systems, focusing on fault systems, source rocks, and reservoir rocks. Investigating the influence of lateral lithostratigraphic heterogeneity on hydrocarbon migration pathways is essential. Moreover, applying 3D modelling techniques to diverse rift basins worldwide will broaden our understanding of hydrocarbon maturation and migration, facilitating more precise resource assessments and exploration strategies. This research advances informed decision-making in hydrocarbon exploration and production.

Photometric correction of images obtained from Chandrayaan-2 Imaging Infra-Red Spectrometer (IIRS) data

India’s second mission to the Moon, Chandrayaan-2, carried one of the most advanced imaging spectrometers ever sent to image a planetary surface – the IIRS (Imaging Infra-Red Spectrometer) – a 250 band spectrometer developed at the Space Applications Centre (SAC), ISRO, India. In this study, IIRS data between 800 and 2000 nm have been used to derive photometrically corrected reflectance from calibrated radiance data supplied by ISRO’s online archive (Pradan) of Chandrayaan-2 data. Additionally, the photometric properties of three IIRS bands (950, 1500, and 1700 nm) have been studied in detail. Since the images obtained by IIRS are at different viewing geometry orientations, the purpose of performing a photometric correction on IIRS images is to re-project each pixel to a standard viewing geometry of incidence angle, i = 30°, emission angle, e = 0° and, phase angle, α = 30°. In order to correct the lunar limb darkening effect, a combination of the Lommel-Seeliger function and McEwen’s model was used. In addition, topographic data from the merged Digital Elevation Model of Lunar Reconnaissance Orbiter – Lunar Orbiter Laser Altimeter (LRO-LOLA) and SELENE Terrain Camera (TC) were utilized to remove effects from local topography. A photometric function was then applied on four images captured by IIRS which were included in the first public release of data in August 2021. Radiance and reflectance (obtained after implementing photometric correction on IIRS images) values were compared with L1 and L2 M3 (Moon Mineralogy Mapper) data from Chandrayaan-1. It was found that although IIRS images are much darker than M3, corrected IIRS reflectance images had a much smaller variation in terms of reflectance values with M3. Moreover, the associated spectral reddening and reflectance values are within range when compared with data from other lunar missions. In addition, the reflectance spectra derived from the corrected IIRS images have been plotted for each image. However, the spectra exhibit significantly deeper absorptions than their corresponding M3 data for the same pixel. Phase functions derived from three bands have a good correlation with the reflectance values and phase angles. Consequently, this function can be applied to all IIRS images as and when more data are released to the public.

Organic petrology and geochemistry of the Devonian-Mississippian bakken formation, Williston Basin, North Dakota

The Devonian–Mississippian (D–M) black shales of the Bakken Formation are of interest as a hydrocarbon source due to their high total organic carbon (TOC; 2.2–17.4%) content. The Upper and Lower Members of the Bakken Fm. are shallow marine (100–150 m) sequences. Thirty samples were selected for maceral identification, kerogen typing, and solid bitumen reflectance (SBRo) based on TOC content and down-core spacing. The shales contain alginite, bituminite, abundant solid bitumen (SB), and minor amounts of inertinite. Solid bitumen increases in quantity with increasing thermal maturity. Pyrolysis (85 samples) provided S1 (avg. 8.0 mg HC/g rock), S2 (avg. 24.3 mg HC/g rock), hydrogen index (HI; avg. 201 mg HC/g TOC), oxygen index (OI; avg. 7 mg CO2/g TOC), and Ro (0.60–1.03%) calculated from Tmax. Plots of HI vs. OI and HI vs. Tmax (°C) were used to assess kerogen type but are not consistently in agreement with the petrographic assessment. Some samples from more thermally mature cores plot as Type III (vitrinite) kerogen instead of Type II (alginite and bituminite) kerogen, the latter confirmed through petrographic observations of lower maturation samples. This is largely due to increased SB in more thermally mature samples (Ro = 0.83–1.03%), as SB is known to have a lower HI content than Type II kerogen. Petrographic data show more alginite and bituminite (19–55%) in the thermally less mature samples (Ro = 0.60–0.83%) compared to more dispersed SB (67–86%) and less alginite and bituminite (<1%) in the more thermally mature samples (Ro = 0.89–1.01%).Early research on the Bakken Fm. reported lower than expected vitrinite reflectance values and attributed them to vitrinite “suppression”. The scarcity of vitrinite and abundance of SB suggest that early work likely reported reflectance on SB. Recent attempts to assess the thermal maturity of the Bakken black shales have converted SBRo to vitrinite reflectance equivalence (VRE). However, there are multiple SB populations present in these shales and it is not always clear which SB populations were included, possibly contributing to error. In the current study, only smooth, homogenous SB was measured (0.68–1.14% SBRo) and VRE values calculated (0.54–1.49%) to assess thermal maturity from the basin margin to the depocenter; inclusion of measurements on granular, heterogeneous SB (14–21 vol%), which are ~53% lower than those for smooth, homogenous SB (3–12 vol%), results in lower mean reflectances, especially in more mature samples. Vitrinite reflectance equivalent data calculated using the D–M New Albany Shale equation of Liu et al. (2019) agrees with liptinite fluorescence and Rock-Eval Ro, whereas VRE based on the D–M Woodford Shale equation of Cardott and Comer (2021) does not. This suggests the importance of applying VRE equations from similar formations both in terms of thermal history, as well as kerogen type and age. Results from SBRo, Rock-Eval Ro, VRE, and observations of alginite fluorescence indicate that samples from the current study range from the early oil window into the condensate, wet gas zone.

Using Remote Sensing Vegetation Indices for the Discrimination and Monitoring of Agricultural Crops: A Critical Review

The agricultural sector is currently confronting multifaceted challenges such as an increased food demand, slow adoption of sustainable farming, a need for climate-resilient food systems, resource inequity, and the protection of small-scale farmers’ practices. These issues are integral to food security and environmental health. Remote sensing technologies can assist precision agriculture in effectively addressing these complex problems by providing farmers with high-resolution lenses. The use of vegetation indices (VIs) is an essential component of remote sensing, which combines the variability of spectral reflectance value (derived from remote sensing data) with the growth stage of crops. A wide array of VIs can be used to classify the crops and evaluate their state and health. However, precisely this high number leads to difficulty in selecting the best VI and their combination for specific objectives. Without thorough documentation and analysis of appropriate VIs, users might find it difficult to use remote sensing data or obtain results with very low accuracy. Thus, the objective of this review is to conduct a critical analysis of the existing state of the art on the effective use of VIs for the discrimination and monitoring of several important agricultural crops (wheat, corn, sunflower, soybean, rape, potatoes, and forage crops), grasslands and meadows. This data could be highly useful for all the stakeholders involved in agricultural activities. The current review has shown that VIs appear to be suitable for mapping and monitoring agricultural crops, forage crops, meadows and pastures. Sentinel-1 and Sentinel-2 data were the most utilized sources, while some of the frequently used VIs were EVI, LAI, NDVI, GNDVI, PSRI, and SAVI. In most of the studies, an array of VIs needed to be employed to achieve a good discrimination of crops or prediction of yields. The main challenges in using VIs are related to the variation of the spectral characteristics during the vegetation period and to the similarities of the spectral signatures of various crops and semi-natural meadows. Thus, further studies are needed to establish appropriate models for the use of satellite data that would prove to have greater accuracy and provide more relevant information for the efficient monitoring of agricultural crops.

Bazı Ekmeklik ve Makarnalık Buğday Çeşitlerinde Sarı Pas Hastalığının Fenolojik Dönemlere göre Hastalık-Verim İlişkisinin Çok Bantlı (Hiperspektral) Veriler Kullanılarak Araştırılması

The aim of this study was to evaluate the severity of yellow rust in different phenological periods by &#x0D; subjecting bread (Bayraktar 2000, Demir 2000, Eser and Kenanbey) and durum (Çeşit-1252, Eminbey, Kızıltan 91 and Mirzabey 2000) wheat varieties to different spore doses (0%, 25%, 50% and 100%) under controlled epidemic conditions. The research was conducted in Yenimahalle, Ankara, Turkey during the 2018-2019 growing season. In the study, the morphological changes in yellow rust severity were determined at different phenological developmental stages of the test materials with the reflectance values obtained by using handheld spectroradiometer in different spore dose applications during the period from tillering to stalk emergence. These reflectance values were converted into vegetation index values expressed by mathematical formulae and used in determining yield estimates. Considering the results obtained, it was determined that the spectral indices calculated especially in the early flowering period (25 May 2019, Feekes 10.5.1) were effective in yield estimation for all bread varieties except Kenanbey variety (15 June 2019, Feekes 10.5.4). It was determined that the spectral band region of 25 May 2019 (Feekes 10.5.1), which includes all indices determined to predict yield in all bread and durum varieties and which is the beginning of flowering, was effective. In grain yield estimation, it was determined that there was a decrease in the correlation values of the spectral indices starting from the early flowering period (Feekes 10.5.1) towards the grain setting period (Feekes 10.5.3) and milk maturity period &#x0D; (Feekes 10.5.4). When the correlations between these index values and yield values were examined, it was &#x0D; determined that prominent phenological periods and high correlation indices could be calculated for these periods. Nowadays, with the use of optical sensor technology instead of traditional disease surveillance methods, the way has paved the way for the development of new approaches for early, fast and accurate yield estimation as a result of the verification of images taken by unmanned aerial vehicles on which multispectral and hyperspectral cameras are located with ground data using artificial intelligence and deep learning techniques.

Effect of shear strain on the electronic and optical properties of Al-doped stanane.

The quasi-metallic properties of stanene limit its prospects in optoelectronic devices. Based on first-principles calculations, a systematic study is conducted on the tuning effects of surface hydrogenation and Al atom doping on the electronic and optical properties of stanene. Surface hydrogenation serves as an ideal way to open the forbidden band of stanene, and Al atom doping further increases hydrogenated stanene (stanane) band gap to 0.460eV. Deformation has a minor impact on the stability of the stanane-Al structure, while shear strain can effectively modulate the band gap engineering of the doped system, reducing the band gap value from 0.460 to 0.170eV. Deformation induces a redshift in the absorption peak and reflectance, also slowing down the rate of decrease in the absorption coefficient, and enhancing the peak value of light reflectance, which is positively correlated with the degree of shear strain. These findings hold promise for expanding the potential application of monolayer stanane in semiconductor devices. All calculations are performed using CASTEP module in Materials Studio based on the density functional theory (DFT). The Perdew-Burke-Ernzerhof (PBE) generalized gradient approximation (GGA) is employed to describe the exchange-correlation energy (Perdew et al., Phys Rev Lett 77(18), 1996). We construct models for both stanene and stanane. The original unit cell of stanene has two Sn atoms, while stanane consists of two Sn atoms and two H atoms, and expand them to a 3 × 3 × 1 supercell with a vacuum layer of 20Å in height to prevent interlayer coupling. After convergence testing, the plane-wave cutoff energy is set to 450eV, and the energy convergence threshold is set to 1 × 10-5eV. The maximum residual stress for each atom is set to 0.01eV/Å. Brillouin zone sampling is performed using a 6 × 6 × 1k-point mesh based on the Monkhorst-Pack method (Monkhorst and Pack, Phys Rev B 13(12), 1976). The k-point accuracy of the density of states and optical properties is 9 × 9 × 1. All calculations are performed using the more advanced OTFG ultrasoft pseudopotential, and structural relaxations are performed using supercells to ensure that the model is fully relaxed. We use the HSE06 functional to calculate the energy band structures of stanane-Al deformed to 0%, 4%, and 8%, resulting in band gap values of 1.465eV, 1.368eV, and 1.016eV, respectively. These values are significantly higher than those obtained using the PBE functional (0.460eV, 0.397eV, and 0.170eV). However, the shapes and trends of the band structures obtained from both PBE and HSE06 calculations are similar. Additionally, the calculation time needed by HSE06 is greatly longer than PBE, which exceeds the capabilities of our computer hardware, and cannot support all subsequent calculations. To investigate the influence of deformations on the variation of band gap values and to conserve computational resources, the subsequent calculations in this study use the PBE functional.

Machine Learning in the Hyperspectral Classification of Glycaspis brimblecombei (Hemiptera Psyllidae) Attack Severity in Eucalyptus

Assessing different levels of red gum lerp psyllid (Glycaspis brimblecombei) can influence the hyperspectral reflectance of leaves in different ways due to changes in chlorophyll. In order to classify these levels, the use of machine learning (ML) algorithms can help process the data faster and more accurately. The objectives were: (I) to evaluate the spectral behavior of the G. brimblecombei attack levels; (II) find the most accurate ML algorithm for classifying pest attack levels; (III) find the input configuration that improves performance of the algorithms. Data were collected from a clonal eucalyptus plantation (clone AEC 0144—Eucalyptus urophilla) aged 10.3 months old. Eighty sample evaluations were carried out considering the following severity levels: control (no shells), low infestation (N1), intermediate infestation (N2), and high infestation (N3), for which leaf spectral reflectances were obtained using a spectroradiometer. The spectral range acquired by the equipment was 350 to 2500 nm. After obtaining the wavelengths, they were grouped into representative interval means in 28 bands. Data were submitted to the following ML algorithms: artificial neural networks (ANN), REPTree (DT) and J48 decision trees, random forest (RF), support vector machine (SVM), and conventional logistic regression (LR) analysis. Two input configurations were tested: using only the wavelengths (ALL) and using the spectral bands (SB) to classify the attack levels. The output variable was the severity of G. brimblecombei attack. There were differences in the hyperspectral behavior of the leaves for the different attack levels. The highest attack level shows the greatest distinction and the highest reflectance values. LR and SVM show better accuracy in classifying the severity levels of G. brimblecombei attack. For the correct classification percentage, the RL and SVM algorithms performed better, both with accuracy above 90%. Both algorithms achieved F-score values close to 0.90 and above 0.8 for Kappa. The entire spectral range guaranteed the best accuracy for both algorithms.

Reflections of nursing students on the care of the person's dignity at the end of life: A qualitative study

BackgroundThe education of nursing students not only implies transmitting knowledge and clinical skills, but also values, attitudes, and behaviours. In healthcare, it is considered essential to respect and preserve the dignity of people. This is even more important in palliative care, where the fragility of people makes them potentially vulnerable. There is limited knowledge regarding the conceptualization and experience of nursing students and human dignity in palliative care. AimTo describe how 5th-year nursing students conceptualise and experience human dignity, while caring for people with terminal illness. DesignQualitative descriptive design, with thematic content analysis as per Graneheim and Lundman. SettingA palliative care centre for people on low incomes with terminal illnesses which no longer respond to curative treatments. ParticipantsA total of 11 fifth-year nursing students who completed their professional practice in a palliative care unit. MethodsData collection was conducted through guided online reflections via reflective journaling between April and November 2020. The study protocol was reviewed and approved by the Scientific Ethical Committee within the educational institution (CEC2021065). ResultsFour thematic categories were identified (1) Concept of dignity; (2) Dignity: an essential element in the relationship with others, (3) Instances when the dignity of the person is not considered; (4) The value of reflection on dignity in clinical practice. ConclusionDignity is one of the main values recognized in the person. Dignity should be promoted in the education of future nursing professionals, particularly with people who are in the final stage of life, where fragility and vulnerability it is more palpable.

Synthesis of High Near-Infrared Reflective Black Pigment Based on YMn2O5

Y(Mn0.95M0.05)2O5 (M = Al, Fe, Ga, Ti, and Zr) samples were synthesized via a sol–gel method using citric acid to find a new near-infrared (NIR) reflective black pigment. Among these samples, the optical reflectance of Y(Mn0.95Fe0.05)2O5 and Y(Mn0.95Ga0.05)2O5 in the near-infrared region was found to be larger than that of YMn2O5. Then, the concentration of the dopant (Fe or Ga) was changed between 0 and 15%, and the resulting UV–Vis–NIR reflectance spectra were measured. As a result, the optical reflectance of the Fe-doped samples decreased in the near-infrared region, while that of the Ga-doped samples increased. Accordingly, Y(Mn1−xGax)2O5 (0 ≤ x ≤ 0.20) samples were synthesized, and the crystal structure, particle size, optical properties, and color of the samples were characterized. The single-phase samples were obtained in the composition range of 0 ≤ x ≤ 0.15, and the lattice volume decreased with increasing Ga3+ concentration. Optical absorption below 850 nm was attributed to the charge transfer transition between O2p and Mn3d orbitals, and the absorption wavelength of Y(Mn1−xGax)2O5 shifted to the shorter wavelength side as the Ga3+ content increased, because of the decrease in the Mn3+ concentration. Although the sample color became slightly reddish black by the Ga3+ doping, the solar reflectance in the near-infrared region reached 47.6% at the composition of Y(Mn0.85Ga0.15)2O5. Furthermore, this NIR reflectance value was higher than those of the commercially available products (R &lt; 45%).