Miracle-dz/UniFAR-FTUs huggingface dataset:
Improved and Validated HPTLC Method for Quantification of Oenothein B and its Use for Analysis of Epilobium angustifolium L.

A selective and simplest possible high-performance TLC (HPTLC) method for quantification of oenothein B on the basis of the free gallic acid and total gallic acid content after acid hydrolysis has been developed and used for analysis of cultivated Epilobium angustifolium. HPTLC of aqueous extracts of E. angustifolium was performed on silica gel with benzene-methanol-acetic acid 90:16:8 (v/v), as mobile phase. Quantitative evaluation of the plate was performed at 570 nm after derivatization with 1% ethanolic FeCl3 solution. The method was validated for precision, repeatability, and accuracy. Average recovery of the active ingredient from the samples was in the range 95.43–104.57%. The calibration plots were linear in the range 440–2200 ng per band. The technique was used, for the first time, for estimation of the oenothein B content of cultivated E. angustifolium, The oenothein B content was highest at budding time (18.4–20.2 mg g−1) and decreased dramatically to 1.0 mg g−1 after flowering.
Sanitizing Effects of Fruit Waxes at High pH and Temperature on Orange Surfaces Inoculated with Escherichia coli

We determined the bactericidal activity of surface applied waxes on oranges. Effective bactericidal activity of combined alkali and heat treatments was observed on both glass slides and orange fruit surfaces. A five log reduction of Escherichia coli was attained by dipping inoculated glass slides in heated (≥50°C) alkaline ( pH 10) wax solution for 4 min. At pH 11, dipping at ≥50°C for ≥2 min achieved similar bactericidal effects. On the fruit surface, wax treatments were effective at the non-stem scar area. Thus, applied fruit waxes may be useful on raw agricultural commodities to reduce surface microbial contaminants.
Carboxyl-tailed ionic liquid promoted aqueous dispersion of multi-walled carbon nanotubes

The present work reports the dispersion of multiwalled carbon nanotubes (MWCNTs) in water using a short chain carboxyl-tailed ionic liquid (IL), 1-carboxymethyl-3-methyl imidazolium tetrafluoroborate ([cmmim][BF4]), as an IL-based hydrophilic surfactant, instead of long-chain hydrophobic ILs. MWCNTs can be dispersed effectively in the aqueous solution of [cmmim][BF4] due to their molecular structure, including one imidazolium ring head group and one carboxyl group with fewer hydrophobic chains. The resulting MWCNT suspensions are stable for more than a month, and no precipitation is observed. The transmission electron microscopy results showed that the structural integrity of MWCNTs did not deteriorate because of their dispersal in water. Ultraviolet–visible–near infrared spectral studies confirm the presence of IL molecules onto the surface of the MWCNTs. X-Ray photoelectron spectroscopy and Fourier transform Raman studies confirmed the cation–π or π–π interactions between the MWCNTs and IL molecules, which makes the suspension of MWCNTs more stable.
Synthesis and Characterization of Comb-Branched Polyelectrolytes. 1. Preparation of Cationic Macromonomer of 2-(Dimethylamino)ethyl Methacrylate by Atom Transfer Radical Polymerization

The synthesis of water-soluble macromonomers of 2-(dimethylamino)ethyl methacrylate (DMAEMA) by atom transfer radical polymerization (ATRP) was studied in detail. The survival of the unsaturated groups in the initiators during the macromonomer preparation as well as the initiator efficiency depended on the nature of initiator and type of ligand used. The kinetics of the ATRP of DMAEMA catalyzed by allyl 2-bromoisobutyrate (ABIB)/copper bromide (CuBr)/N,N,N‘,N‘,N‘ ‘-pentamethyldiethylenetriamine (PMDETA) system at different conditions indicated that the low initiator efficiency of the ATRP system could not be improved by increasing temperature or changing solvents. It was found that ABIB/CuBr/tris(2-di(butylacrylate)aminoethyl)amine (BA6-TREN) and allyl trichloroacetamide (ATCA)/CuBr/BA6-TREN gave high initiator efficiencies and excellent control over the molecular weights and molecular weight distributions in the ATRP of DMAEMA. 1H NMR studies confirmed that each polyDMAEMA chain had a polymerizable allyl.
Structural Growth Sequences and Electronic Properties of Zinc Oxide Clusters (ZnO)n (n=2-18)

The structural and electronic properties of (ZnO)n (n = 2−18) clusters are studied using gradient-corrected density-functional theory (DFT). The starting structures are generated from empirical genetic algorithm simulations or handmade constructions with chemical intuition. The lowest-energy structures of (ZnO)n are then selected from a number of structural isomers via DFT optimization. For small clusters (n = 2−7), ring structures were found to be the most stable. Three-dimensional cage and tube structures become energetically preferable for larger clusters (n = 9−18), and the competition between cage and tube structures leads to the alternative appearance of these two types of structures as global minima. The size evolution of electronic properties for zinc oxide clusters from ring toward cage or tube is discussed.
Surface structure, hydration, and cationic sites of nanohydroxyapatite: UHR-TEM, IR, and microgravimetric studies

A multi-technique study devoted to investigate the surface features of nanosized hydroxyapatite (HA) was carried out. UHR-TEM observation provided evidence that HA nanoparticles are constituted by a crystalline core, elongated in the direction of the crystallographic c-axis, coated by an amorphous layer 1−2 nm thick. By means of IR spectroscopy and microgravimetry, the amount of water and hydroxy groups on the surface was evaluated. For the as-prepared material, it was found that the first hydration layer is mainly constituted by H2O molecules interacting through a coordinative bond with Ca2+ in a 1:1 ratio, while hydroxy groups account only for ca. 20% of surface hydration species. Outgassing at increasing temperatures up to 300 °C resulted in a complete surface dehydration, accompanied by a decrease of the capability to readsorb water. Possible changes of the local structure of surface Ca2+ ions were probed by IR spectra of adsorbed CO. The combination of these data with rehydration tests suggested that.
Influence of Multiwalled Carbon Nanotubes on Mechanical, Thermal and Electrical Behavior of Polybenzoxazine-Epoxy Nanocomposites

Multiwalled carbon nanotubes (MWCNT)-reinforced polybenzoxazine-epoxy nanocomposites were prepared via the solvent method and were investigated for their thermal, thermo-mechanical, mechanical, electrical and morphological properties. Epoxy resin (DGEBA) was modified with 5, 10 and 15 wt. % of benzoxazines using 4,4′-diaminodiphenylmethane as a curing agent at appropriate conditions. Epoxy and benzoxazines-modified epoxy systems were further reinforced with 0.25, 0.50 and 0.75 wt. % of surface-modified MWCNT. MWCNT-reinforced polybenzoxazine-epoxy nanocomposites exhibited better thermal, mechanical and dielectric properties. Dispersion of MWCNT in benzoxazine-epoxy resins and nanostructure of the composites was confirmed by transmission electron microscopy analysis. GRAPHICAL ABSTRACT
Nature of second-order nonlinear optical response in phthalocyanine derivatives: a density functional theory study

Density functional theory was employed to investigate a series of phthalocyanine derivatives, discovering the limitation when the expansion of the conjugated system was employed to improve the hyper-Rayleigh scattering response coefficient. Furthermore, an unusually C\infty v-type octupolar population was found by electrostatic potential analysis. In addition, the dynamic and static hyper-Rayleigh scattering responses (bHRS) were simulated using the coupled perturbed density functional theory, showing an increasing dynamic bHRS value along with an increase in incident light energy.
Usefulness of endoscopic ultrasound-guided fine needle aspiration for splenic parenchyma in patients suspected of having primary splenic malignant lymphoma

Abstract Background and study aims The diagnosis of malignant lymphoma (ML) is sometimes difficult, especially in patients with primary splenic malignant lymphomas (psML) which have no lymph nodes capable of acting as the biopsy target. We carried out endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) for “splenic parenchyma” in patients suspected of having a psML, even without any obvious neoplastic lesions in the spleen. Patients and methods A retrospective study using medical records was conducted of eight patients suspected of having a psML that received EUS-FNA for the splenic parenchyma between January 2016 and January 2019. Data analyzed included clinical background, EUS-FNA procedure (puncture needle/route), diagnostic ability (pathological/flow cytometry [FCM]), and complications. Results EUS-FNA was performed from the stomach in all eight cases, and no patients had complications. As a result of splenic parenchymal biopsy found on EUS-FNA, 75 % of patients (6/8) were histologically diagnosed with MLs, monoclonality of B-cells was identified in all cases (8/8) with FCM, and all patients (8/8) were definitively diagnosed with psMLs. Conclusion EUS-FNA for “splenic parenchyma” is useful for patients with spML, even if they have no obvious neoplastic lesions in the spleen.
Protein Heat Capacity: An Anomaly that Maybe Never Was

Protein unfolding in aqueous solution is usually accompanied by an increase in heat capacity (ΔCp), and this has long been regarded as somewhat anomalous. However, neither the absolute heat capacities (Cp) of folded globular proteins nor the heat capacity increments upon unfolding (ΔCp) are unusual in comparison to values observed for order−disorder (melting) transitions in other organic substances. The consequences for protein stability, including cold denaturation, enthalpy−entropy compensation, and the temperature of maximum stability, may seem counterintuitive but should not be unexpected. Nevertheless, while perhaps not so anomalous as once thought, quantitative interpretation of protein heat capacity and related effects remains a theoretical challenge.
Rapid Normal Raman Spectroscopy of Sub-Ppm Oxy-Anion Solutions: The Role of Electrophoretic Preconcentration

Normal Raman spectroscopy is used as an on-line detector for capillary electrophoresis (CE) to detect sub-ppm mixtures of nitrate and perchlorate in water. Field-amplified injection, a form of sample stacking, into a running electrolyte of 0.1 M KCl increases the analyte concentration at the detection window by up to 1800 times its starting value. Raman bands of nitrate (1047 cm−1) and perchlorate (934 cm−1) are measured in a total separation time of less than 3 min, with only 1-s integration times. The Raman spectroscopy of solutions originally 1 × 10−5 M nitrate (620 ppb) and perchlorate (1 ppm) is demonstrated.
Structure of [P(CH3)4]2CuBr4 at 293 K

[P(CH 3 ) 4 ] 2 CuBr 4 cristallise dans P2 1 /b11 avec a=9,493, b=31,673, c=13,046 A, α=90,17 o , Z=8; affinement jusqu'a R=0,064. La calorimetrie differentielle a balayage montre deux transitions de phase a 193 et a 404 K, respectivement. Le groupe d'espace Pmcn et les parametres cristallins de la phase haute temperature sont aussi determines par des photographies aux rayons X en precession. La structure monoclinique est une deformation calculable de la phase orthorhombique
Systematic Comparison of Heatmapping Techniques in Deep Learning in the Context of Diabetic Retinopathy Lesion Detection

Purpose Heatmapping techniques can support explainability of deep learning (DL) predictions in medical image analysis. However, individual techniques have been mainly applied in a descriptive way without an objective and systematic evaluation. We investigated comparative performances using diabetic retinopathy lesion detection as a benchmark task. Methods The Indian Diabetic Retinopathy Image Dataset (IDRiD) publicly available database contains fundus images of diabetes patients with pixel level annotations of diabetic retinopathy (DR) lesions, the ground truth for this study. Three in advance trained DL models (ResNet50, VGG16 or InceptionV3) were used for DR detection in these images. Next, explainability was visualized with each of the 10 most used heatmapping techniques. The quantitative correspondence between the output of a heatmap and the ground truth was evaluated with the Explainability Consistency Score (ECS), a metric between 0 and 1, developed for this comparative task. Results In case of the overall DR lesions detection, the ECS ranged from 0.21 to 0.51 for all model/heatmapping combinations. The highest score was for VGG16+Grad-CAM (ECS = 0.51; 95% confidence interval [CI]: [0.46; 0.55]). For individual lesions, VGG16+Grad-CAM performed best on hemorrhages and hard exudates. ResNet50+SmoothGrad performed best for soft exudates and ResNet50+Guided Backpropagation performed best for microaneurysms. Conclusions Our empirical evaluation on the IDRiD database demonstrated that the combination DL model/heatmapping affects explainability when considering common DR lesions. Our approach found considerable disagreement between regions highlighted by heatmaps and expert annotations. Translational Relevance We warrant a more systematic investigation and analysis of heatmaps for reliable explanation of image-based predictions of deep learning models.
Photoactivity of Transparent Nanocrystalline Fe2O3 Electrodes Prepared via Anodic Electrodeposition

Highly transparent nanocrystalline α-Fe2O3 films were prepared via anodic electrodeposition using a slightly acidic aqueous medium (pH 4.1). The deposition mechanism involved oxidation of Fe2+ ions to Fe3+ ions followed by precipitation of Fe3+ ions as amorphous γ-FeOOH films. The as-deposited films were then converted to transparent nanocrystalline α-Fe2O3 films by annealing at 520 °C in air. The as-deposited and annealed films were characterized by Raman and UV−vis spectroscopy, X-ray diffraction, and scanning electron microscopy. The photoactivity of the as-deposited and annealed films was studied by measuring short-circuit photocurrents in a 60:40 solution of propylene carbonate:acetonitrile containing 0.5 M tetrabutylammonium iodide and 0.04 M iodine. Both films show n-type behavior generating anodic photocurrent. α-Fe2O3 films with various thicknesses were prepared to study the effect of film thickness on photon absorption and photocurrent. The short-circuit photocurrent of α-Fe2O3 films increased g.
Fossil Sources of Ambient Aerosol Carbon Based on 14C Measurements Special Issue of Aerosol Science and Technology on Findings from the Fine Particulate Matter Supersites Program

Organic and elemental carbonaceous material constitute significant portions of PM10 and PM2.5 mass on a global basis and are typically 35% and 10%, respectively, in urban areas of the southeastern United States. The organic portion of this is a complex mixture of primary compounds and secondary materials formed in situ from primary emissions. These materials derive from a variety of sources that are dynamically changing in time and space, making difficult the quantitative characterization of their sources. Results of measurements of the 14C content of organic aerosol particles (PM10 and TSP) sampled at Look Rock, TN are reported in this work with the aim of better estimating bounds to fossil and biogenic sources that contribute to PM mass concentrations. The fraction of fossil-derived carbon in these particles has been estimated as 1 minus the fraction of “modern” carbon, the latter by definition biologically synthesized in equilibrium with atmospheric, cosmic ray-derived 14CO2. Fossil carbon fractions vary in a wide range from less than 10 to about 60% during spring, summer, and fall seasons at this ridge-top site near the Great Smoky Mountains National Park. The implications of these findings on control strategies for the organic carbon fraction of PM2.5 mass are discussed.
Sorção e persistência da sorgoleona em um Latossolo Vermelho-Amarelo

The root exudates produced by sorghum contain a biologically active constituent known as sorgoleone. The behavior of sorgoleone in a Red-Yellow Latosol was studied. The sorption model of sorgoleone in soil was better adjusted to the Freundlich equation, through the coefficients Kf (capacity of sorption) and 1/n (linearity of the isotherm). The persistence of sorgoleone in soil and its possible degradation were also evaluated by monitoring their residues in the soil along the time. Recovery rate of sorgoleone from the soil reached 93% after 24h. It was verified that sorgoleone is strongly sorbed in the soil and its half-life is 10 days, under the experimental conditions. The presence of sorgoleone or its metabolites was not detected in the soil after 60 days.
Quantification and potential aroma contribution of β‐ionone in marine salt

A methodology for quantification of β-ionone in marine salt was developed using the headspace solid phase microextraction and gas chromatography–quadrupole mass spectrometry (HS–SPME/GC–qMS). Quantification of β-ionone was achieved by linear regression from an analytical plot of pure standard using the target ion at m/z 177 by ion extraction chromatography (IEC). HS–SPME/GC–qMS combined with IEC mode allowed quantification of trace levels (ng/l) of β-ionone in marine salt aqueous solutions. The methodology developed presented a good linearity (R2 = 0.981) for the range of concentrations used (16 a 568 ng/l) and a good reproducibility (15%), with limits of detection and quantification of 9 and 29 ng/l, respectively. This methodology was applied to marine salt from different geographical origins (Portugal, France, and Cape Verde). Estimated concentrations of β-ionone in marine salt varied from 241 to 888 ng/kg of salt. The highest values were found for Aveiro, in Portugal, and Guerande, in France, in environments surrounded by a large number of plant and algae diversity. However, in Castro Marim and Tavira (in Algarve, South of Portugal), this compound was not found. According to the odour threshold of β-ionone in water (30 ng/l), aqueous solutions with more than 100 g/l of marine salt can exhibit a violet odour. Similar conditions can occur in the ponds with higher levels of salinity of the traditional saltpans. This methodology proved to be a useful tool for screening and quantification of β-ionone, a compound shown to present potential contribution to marine salt aroma. Copyright © 2010 John Wiley & Sons, Ltd.
Contaminations Of Heavy Metals In Water And Hemichromis fasciatus Of A Waste Pit Influenced By Petroleum Activities

The concentrations of heavy metals (Zn, Cd, Cu, Pb, Ni, Fe, Mn, Co, Cr, V and Hg) in water and Hemichromis fasciatus (a piscivore) in the burrow pit constructed by Shell Petroleum Development Company were studied. Water and fish samples were collected monthly from January to December 2000. The range values (mg/l) of heavy metals in water were: Zn (0.025 – 2.91), Cd (BD – 0.044), Cu (BD – 0.106), Pb (0.001 – 0.252), Ni (BD – 0.14), Fe (0.143 – 5.204), Mn (0.025 – 0.138), Co (BD – 0.202), Cr (0.002 – 0.018), V (BD – 0.005) and Hg (BD – 0.001) while in Hemichromis fasciatus , values (mg/kg) were Zn (15.28 – 90.93), Cd (BD – 5.04), Cu (0.42 – 5.82), Pb (0.03 – 3.43), Ni (0.36 – 1.71), Fe (43.16 – 145.24), Mn (2.16 – 5.74), Co (BD – 1.63), Cr (BD – 1.61), V (BD – 0.12) and Hg (BD =below detection level). Seasonally, Cd, Cu, Pb, Mn, Co, Cr, V and Hg had higher mean values in water during the dry season while Zn, Ni and Fe were higher during the raining season. All heavy metals except Fe were higher in mean values during the dry season in H. fasciatus than during the rainy season. The mean abundance of heavy metals in H. fasciatus was Fe>Zn>Mn>Cu>Cd>Co>Pb>Ni>Cr>V. The monthly concentrations of heavy metals in H. fasciatus were far higher than those in water. The concentrations of Pb, Fe and Mn were above WHO limits for drinking water for some months while Fe and Mn values in H. fasciatus were above WHO limits for food in twelve months with Zn, Cd, Cu, Pb, Ni, Co and Cr exceeding WHO limits for some months. The findings reveal that the water and the fish ( H. fasciatus ) are contaminated and not fit for drinking and consumption by humans. Keywords : Heavy metals, water, fish, seasonality, distribution coefficients, burrow pit, Niger Delta, Nigeria. Tropical Freshwater Biology Vol. 16 (2) 2007: pp. 45-56
Density and Structure of Liquid Si-M (M=Fe, Ni, and Ge) Alloys

In order to elucidate a link between density and structure of liquid Si-M (M=Fe, Ni, and Ge) alloys, synchrotron x-ray diffraction experiments have been conducted with the use of a conical nozzle levitation technique. Liquid structure factors of the Si-Fe and the Si-Ni alloys indicate a correlation of medium range ordering with the increase of the Si content. Although the total molar volume expands with the increase of the Si content in these alloys, the concentration dependence of the average interatomic distance shows a minimum around 70 at. % Si content. On the other hand, the Si-Ge alloys shows tendency of concentration dependence as ideal mixture in both total molar volume and the average interatomic distance. These results were discussed taking into account the formation of anisotropic bonds between 3 d transition metal and Si atoms, which may induce a spatial expansion in the microscopic scale.
Traps created at the interface between the nitride and the oxide on the nitride by thermal oxidation

Traps introduced by thermal oxidation of a thin nitride film have been investigated using metal‐oxide (top‐oxide)‐nitride‐oxide‐semiconductor memory diodes. Memory properties as a function of the initial nitride thickness before thermal oxidation and the top‐oxide thickness have revealed that the newly created traps are situated mostly at the top‐oxide‐nitride interface. The density of the traps is estimated to be (1.6±0.2)×1013/cm2 independent of the initial nitride thickness and the top‐oxide thickness.
Liquid Crystal Metamaterial Absorber Spatial Light Modulator for THz Applications

A terahertz (THz) spatial light modulator implemented with metamaterial absorbers (MMAs) functionalized with isothiocyanate‐based liquid crystals (LCs) is experimentally demonstrated. The device is designed to work in reflection mode and is arranged in a 6 × 6 pixel matrix where the response of each pixel is modulated by electronically controlling the orientation of liquid crystal dimers covering the entire metamaterial absorber landscape. Experiments show that each pixel can be controlled independently and that pixelated absorption patterns can be created at will. The SLM shows an overall modulation depth of 75%. Furthermore, computational results show that losses arising from LCs impose a severe limitation on the overall performance and that consequently the modulation depth of each pixel could be improved with liquid crystal mixtures designed primarily for THz frequencies. This work demonstrates the viability of liquid crystal‐based reconfigurable metamaterials and highlights their great potential use for future state‐of‐the‐art THz devices.