Miracle-dz/UniFAR-FTUs huggingface dataset:
Inhibitory effect of soil humic compounds on the proteolytic enzyme pronase

Neutralized solutions of soil humic acids inhibit the proteolytic activity of the enzyme pronase when tested against a variety of substrates. Protein hydrolysis was less sensitive than hydrolysis of dipeptide derivatives; 50% inhibition of benzyloxycarbonylglycylleucine hydrolysis was achieved with concentrations of humic acids as low as 1-2 µg/ml or less than 10-5M, on a carboxyl group basis. Humic acids, extracted from soils with different crop histories, showed only slight differences in their effectiveness as inhibitors of pronase activity. Their inhibitory power was comparable with that of other high molecular weight polyanions, e.g. polyacrylic acid and polycondensates derived from p-benzoquinone and catechol. Alginic acid was a relatively poor inhibitor. Preincubation of humic acids for various periods with either pronase or substrate (albumin or benzyloxycarbonylglycylleucine) had little or no effect on the subsequent inhibition of enzymic activity. However, inhibition is decreased by increasing substrate concentrations, following preincubation of humic acids and pronase. Both observations are consistent with a reversible inhibitory mechanism. Kinetic studies demonstrate that humic acids inhibit pronase activity towards albumin and N-benzyloxycarbonyl dipeptides by effectively reducing the affinity of pronase for the substrate, i.e. by increasing the Km value for the reaction. With benzoylarginine amide and benzoylarginine ethyl ester as substrates, the reaction velocity is lowered due to a reduction of the maximum velocity of the system. Both effects may possibly be explained by a conformational change in the enzyme structure due to combination with the humic acid molecules.
Moving target localization in noncoherent distributed MIMO radar systems using range and range rate measurements

This paper considers the problem of moving target localization in noncoherent distributed multiple-input multiple-output (MIMO) radar systems by using the bistatic range and range rate measurements. We propose a weighted least squares (WLS) method to estimate the target position and velocity, and then use the semidefinite programming (SDP) method to improve the accuracy of the WLS estimation by relaxing the constraints that exist in the WLS solution. Simulation results are included to show the performance of the proposed algorithm. It is shown that the proposed method can reach the Cramer-Rao lower bound (CRLB) in a range of moderate measurements noise, and the proposed algorithm is robust to some special geometries, in which the two-step weighted least squares-based (2SWLS-based) methods will be failed.
The effect of Banana Xanthomonas Wilt on beer-banana value chains in central Uganda: An exploratory study

Purpose - – Beer-bananas in Central Uganda are important for smallholder farmers’ livelihoods, especially for those that process the banana into beer and spirits. The purpose of this paper is to understand how actors in the beer-banana value chain are affected and how they are managing disease has become an important issue since the outbreak of the bacterial banana disease Xanthomonas Wilt. Design/methodology/approach - – The authors conducted an exploratory study focusing on producers of beer-bananas; brewers and non-brewers, and on retailers in Central Uganda and in Kampala. The authors conducted surveys with these value chain actors and we used baseline data, collected through a household survey in the project sites. Findings - – Results showed that Banana Xanthomonas Wilt (BXW) has drastically reduced productivity of beer-banana systems, resulting in reduced sales volumes of beer-bananas and processed products and consequently reduced incomes. Application of disease control measures was generally higher among those farmers that brew. Research limitations/implications - – This being an exploratory study, the samples for the different value chain actors were rather small. Future research should address: product quality and opportunities for differentiation; effects of beer-banana processing on rural communities; adoption of BXW control measures. Originality/value - – Beer-bananas are often neglected in research; this paper shows that is unfounded since beer-banana production and processing are important for many people’s livelihood. More insight into what motivates farmers to control the disease is essential to protect these people’s livelihoods.
Etude du transfert d’eau et de solutés dans un sol à nappe superficielle drainée artificiellement

La comprehension des mecanismes de transport de solutes dans un milieu poreux variablement sature tel que les sols a nappe drainee par tuyaux enterres, est essentielle afin de repondre aux interrogations concernant l'impact de ces systemes sur la qualite des eaux de surface. L'approche choisie repose sur des experiences de tracage realisees en regime permanent sur modele physique de sol au laboratoire, permettant un controle des conditions initiales et aux limites. La premiere partie de la these est dediee aux etudes monodimensionnelles, afin de caracteriser la zone non saturee du sol. Nous avons utilise une colonne de sol (1*0,15 m²) et un modele physique de grande taille (1*2*0,5 m3), remplis tous deux d'un sol sablo-limoneux. Les traceurs utilises sont le H218O et le Cl-. La deuxieme partie du travail traite le cas des ecoulements bidimensionnels, realisees uniquement sur le modele physique. Deux scenarios ont ete choisis : un solute apporte en surface et un solute residant dans le sol. Seul le Cl- a alors ete utilise comme traceur. Le transport de solutes a ete etudie par un suivi in situ (sondes de conductivite electrique) ainsi qu'a l'exutoire du systeme. L'analyse des courbes d'elution obtenues pour les etudes monodimensionnelles a permis l'identification des mecanismes de transport et le calcul des parametres de transport pertinents (par resolution inverse). Pour les experiences bidimensionnelles, il a ete observe une heterogeneite des champs de vitesses, avec une zone proche du drain ou le lessivage est rapide et une zone proche de l'interdrain ou le solute progresse a faible vitesse. Dans le cas du solute residant dans le sol, les courbes d'elution (concentration et conductivite electrique) au drain montrent un palier stable puis une diminution de forme « exponentielle » jusqu'a atteindre les concentrations du niveau de base. La migration du solute dans le cas d'un pulse apporte en surface du sol est singulier. La courbe d'elution en sortie du drain presente deux modes : (i) un premier mode sous forme d'un pic, (ii) et le deuxieme sous forme d'un palier constant de concentration. Ces resultats experimentaux ont ete confrontes a la modelisation mecaniste (code HYDRUS-2D), utilisant les parametres de transport obtenus dans les etudes monodimensionnelles. L'utilisation d'une deuxieme methode, le suivi de particules (approche lagrangienne), nous a permis d'obtenir le cheminement de l'eau et le temps de transfert des particules dans le sol.
Wave energy focusing to subsurface poroelastic formations to promote oil mobilization

S U M M A R Y We discuss an inverse source formulation aimed at focusing wave energy produced by ground surface sources to target subsurface poroelastic formations. The intent of the focusing is to facilitate or enhance the mobility of oil entrapped within the target formation. The underlying forward wave propagation problem is cast in two spatial dimensions for a heterogeneous poroelastic target embedded within a heterogeneous elastic semi-infinite host. The semi-infiniteness of the elastic host is simulated by augmenting the (finite) computational domain with a buffer of perfectly matched layers. The inverse source algorithm is based on a systematic framework of partial-differential-equation-constrained optimization. It is demonstrated, via numerical experiments, that the algorithm is capable of converging to the spatial and temporal characteristics of surface loads that maximize energy delivery to the target formation. Consequently, the methodology is well-suited for designing field implementations that could meet a desired oil mobility threshold. Even though the methodology, and the results presented herein are in two dimensions, extensions to three dimensions are straightforward.
Incidence rate of first‐time symptomatic urinary tract infection in children under 6 years of age

A retrospective population‐based study was performed to describe the incidence rate of first time symptomatic urinary tract infection in children under 6 y of age. A total number of 299 children was identified during the 20‐month study period in a population of 20 000 girls and 21 000 boys. The cumulative incidence rate during the first 6y of life was 6.6% for girls and 1.8% for boys. The annual incidence rate in girls of urinary tract infection/1000 at risk was between 9 and 14 for each of the six 1‐y age intervals. In girls, the proportion of febrile urinary tract infection was high during the infant year, while girls older than 2 y most often had non‐febrile infection. For infant boys, the incidence rate and the proportion of febrile urinary tract infection were comparable to that of girls, while after the first year of life urinary infection of any kind was rare, with an incidence rate of 1–2/1000 at risk.
Reprocessing and Characterization of Long-duration Tremor Signals from a Hydraulic-fracture Treatment in Western Canada

The Hoadley flowback microseismic experiment (HFME) was undertaken commencing August 2012 for long-term passive seismic monitoring in a open-hole multistage hydraulic fracture treatment in the Glauconitic member (Hoadley gas field, central Alberta). The scientific goals of this project were to document and develop a geomechanical model for microseismic activity associated with flowback and production stages of development of a tight-gas reservoir. About 1650 events were located during the two-day hydraulic fracture treatment program. The distribution of microseismicity revealed a relatively complex fracture pattern. The objectives of this study are twofold. First, complete reprocessing of the raw microseismic data has been undertaken using in-house software, with the goal of improving the understanding of the relationship between source type (shear versus tensile) and the treatment parameters. The second goal is to characterize long-duration tremor-like events that occurred episodically during and after treatment. These events are interpreted as activation of slow slip on pre-existing fractures. Two of these tremor-like events occurred during the postpumping period after the second day of treatment; they both exhibit frequency characteristics that are consistent with a slowly cascading rupture process.
Two's Company, Three's a Crowd: Experimental Evaluation of the Evolutionary Maintenance of Trioecy in Mercurialis annua (Euphorbiaceae)

Trioecy is an uncommon sexual system in which males, females, and hermaphrodites co-occur as three clearly different gender classes. The evolutionary stability of trioecy is unclear, but would depend on factors such as hermaphroditic sex allocation and rates of outcrossing vs. selfing. Here, trioecious populations of Mercurialis annua are described for the first time. We examined the frequencies of females, males and hermaphrodites across ten natural populations and evaluated the association between the frequency of females and plant densities. Previous studies have shown that selfing rates in this species are density-dependent and are reduced in the presence of males, which produce substantially more pollen than hermaphrodites. Accordingly, we examined the evolutionary stability of trioecy using an experiment in which we (a) indirectly manipulated selfing rates by altering plant densities and the frequency of males in a fully factorial manner across 20 experimental plots and (b) examined the effect of these manipulations on the frequency of the three sex phenotypes in the next generation of plants. In the parental generation, we measured the seed and pollen allocations of hermaphrodites and compared them with allocations by unisexual plants. In natural populations, females occurred at higher frequencies in denser patches, a finding consistent with our expectations. Under our experimental conditions, however, no combination of plant densities and male frequencies was associated with increased frequencies of females. Our results suggest that the factors that regulate female frequencies in trioecious populations of M. annua are independent of those regulating male frequencies (density), and that the stable co-existence of all three sex phenotypes within populations is unlikely.
Possible causes for a negative shift in the stable carbon isotope ratio before, during and after the end-Permian mass extinction in Meishan, South China

A 2–4‰ negative shift of δ13C has been reported from many Permian/Triassic (P/Tr) boundary sections around the world. Our carbon isotopic measurements of bulk carbonate and organic matter from the Meishan section, South China show that a –3‰ shift of δ13C spanned ∼30 ka over the end-Permian mass extinction. Carbon isotopic excursions (δ13Ccarb, δ13Corg) coupled with Δ13C (=δ13Ccarb–δ13Corg), marine kerogen %, 87Sr/86Sr of siliciclastics and total organic carbon show geochemical signals underwent six geochemical variation zones (GVZ) over the P/Tr transition. Of these, GVZ 1 corresponds to the lower–middle parts of Bed 24e-1, GVZ 2 to the upper part of Bed 24e-1, GVZ 3 to Beds 24e-2, 24e-3, 25-2 and 25-2, GVZ 4 to Bed 25-3, GVZ 5 to Bed 26, and GVZ 6 to Beds 27–29. A −1‰ shift of δ13C within ∼13 ka before the main extinction was probably generated by possible dissociation of methane hydrate by warming. Subsequent mixing of anoxic stratified ocean led to another −1‰ shift of δ13C within ∼5 ka during the extinction. The −1‰ shift of δ13C within ∼13 ka after the main extinction has probably resulted from massive denudation of soil and sediments caused by the collapse of forests and possible dissociation of methane hydrate at the end of the Permian. Furthermore, a dramatic drop of Δ13C values from 29–30‰ in Bed 24e-3 to 25‰ in Bed 25 indicates an abrupt proliferation of phototrophic sulfur bacteria immediately after the main episode of the end-Permian mass extinction. The Δ13C value increases to 29–30‰ in Bed 26 again, and this is probably due to massive denudation of soil and sediment caused by the collapse of forests between 0 and 27 ka after the main extinction, as revealed by negative shift of δ13C. Low Δ13C value recorded in Beds 27–29 indicates that phototrophic sulfur bacteria may have thrived again and lasted more than 150 ka after the main extinction in the low-latitude Paleo-Tethys.
Traveltimes for global earthquake location and phase identification

SUMMARY Over the last three years, a major international effort has been made by the Sub-Commission on Earthquake Algorithms of the International Association of Seismology and the Physics of the Earth's Interior (IASPEI) to generate new global traveltime tables for seismic phases to update the tables of Jeffreys & Bullen (1940). The new tables are specifically designed for convenient computational use, with high-accuracy interpolation in both depth and range. The new iasp91 traveltime tables are derived from a radially stratified velocity model which has been constructed so that the times for the major seismic phases are consistent with the reported times for events in the catalogue of the International Seismological Centre (ISC) for the period 1964–1987. The baseline for the P-wave traveltimes in the iasp91 model has been adjusted to provide only a small bias in origin time for well-constrained events at the main nuclear testing sites around the world. For P-waves at teleseismic distances, the new tables are about 0.7s slower than the 1968 P-tables (Herrin 1968) and on average about 1.8–1.9 s faster than the Jeffreys & Bullen (1940) tables. For S-waves the teleseismic times lie between those of the JB tables and the results of Randall (1971). Because the times for all phases are derived from the same velocity model, there is complete consistency between the traveltimes for different phases at different focal depths. The calculation scheme adopted for the new iasp91 tables is that proposed by Buland & Chapman (1983). Tables of delay time as a function of slowness are stored for each traveltime branch, and interpolated using a specially designed tau spline which takes care of square-root singularities in the derivative of the traveltime curve at certain critical slownesses. With this representation, once the source depth is specified, it is straightforward to find the traveltime explicitly for a given epicentral distance. The computational cost is no higher than a conventional look-up table, but there is increased accuracy in constructing the traveltimes for a source at arbitrary depth. A further advantage over standard tables is that exactly the same procedure can be used for each phase. For a given source depth, it is therefore possible to generate very rapidly a comprehensive list of traveltimes and associated derivatives for the main seismic phases which could be observed at a given epicentral distance.
Star Formation in NGC 5194 (M51a): The Panchromatic View from GALEX to Spitzer

Far-ultraviolet to far-infrared images of the nearby galaxy NGC 5194 (M51a), from a combination of space-based (Spitzer, GALEX, and Hubble Space Telescope) and ground-based data, are used to investigate local and global star formation and the impact of dust extinction. The Spitzer data provide unprecedented spatial detail in the infrared, down to sizes ~500 pc at the distance of NGC 5194. The multiwavelength set is used to trace the relatively young stellar populations, the ionized gas, and the dust absorption and emission in H II-emitting knots, over 3 orders of magnitude in wavelength range. As is common in spiral galaxies, dust extinction is high in the center of the galaxy (AV ~ 3.5 mag), but its mean value decreases steadily as a function of galactocentric distance, as derived from both gas emission and stellar continuum properties. In the IR/UV-UV color plane, the NGC 5194 H II knots show the same trend observed for normal star-forming galaxies, having a much larger dispersion (~1 dex peak to peak) than starburst galaxies. We identify the dispersion as due to the UV emission predominantly tracing the evolved, nonionizing stellar population, up to ages ~50-100 Myr. While in starbursts the UV light traces the current star formation rate (SFR), in NGC 5194 it traces a combination of current and recent past SFRs. Possibly, mechanical feedback from supernovae is less effective at removing dust and gas from the star formation volume in normal star-forming galaxies than in starbursts because of the typically lower SFR densities in the former. The application of the starburst opacity curve for recovering the intrinsic UV emission (and deriving SFRs) in local and distant galaxies appears therefore appropriate only for SFR densities ≳1 M☉ yr-1 kpc-2. Unlike the UV emission, the monochromatic 24 μm luminosity is an accurate local SFR tracer for the H II knots in NGC 5194, with a peak-to-peak dispersion of less than a factor of 3 relative to hydrogen emission line tracers; this suggests that the 24 μm emission carriers are mainly heated by the young, ionizing stars. However, preliminary results show that the ratio of the 24 μm emission to the SFR varies by a factor of a few from galaxy to galaxy; this variation needs to be understood and carefully quantified before the 24 μm luminosity can be used as an SFR tracer for galaxy populations. While also correlated with star formation, the 8 μm emission is not directly proportional to the number of ionizing photons; it is overluminous, by up to a factor of ~2, relative to the galaxy's average in weakly ionized regions and is underluminous, by up to a factor of ~3, in strongly ionized regions. This confirms earlier suggestions that the carriers of the 8 μm emission are heated by more than one mechanism.
Charge transfer between oxygen atoms and O+ and H+ ions

The cross sections for charge transfer between O atoms and O+ and H+ ions have been determined within the energy range 40 to 10,000 ev in a crossed-beam experiment. These processes are of unusual interest because of their influence on the motion and composition of the earth's high atmosphere. It is observed that the variation of the cross section Q with energy E for each of these processes can be well represented by an expression of the form Q½ = a - b log E, which is characteristic of symmetric resonance charge transfer. The magnitudes of these cross sections at energies appropriate to those in the upper atmosphere are estimated. The O atoms used in these measurements were obtained from an electrodeless RF discharge; the ions were extracted from an electron-bombardment ion source. The influence of excited states on the measurements is estimated.
Effects of Saponins on Lipid Metabolism: A Review of Potential Health Benefits in the Treatment of Obesity

Obesity is one of the greatest public health problems. This complex condition has reached epidemic proportions in many parts of the world, and it constitutes a risk factor for several chronic disorders, such as hypertension, cardiovascular diseases and type 2 diabetes. In the last few decades, several studies dealt with the potential effects of natural products as new safe and effective tools for body weight control. Saponins are naturally-occurring surface-active glycosides, mainly produced by plants, whose structure consists of a sugar moiety linked to a hydrophobic aglycone (a steroid or a triterpene). Many pharmacological properties have been reported for these compounds, such as anti-inflammatory, immunostimulant, hypocholesterolemic, hypoglycemic, antifungal and cytotoxic activities. The aim of this review is to provide an overview of recent studies about the anti-obesity therapeutic potential of saponins isolated from medicinal plants. Results on the in vitro and in vivo activity of this class of phytochemicals are here presented and discussed. The most interesting findings about their possible mechanism of action and their potential health benefits in the treatment of obesity are reported, as well.
Tracking Scientometric Research in Taiwan Using Bibliometric and Content Analysis

This study used bibliometric analysis and content analysis to explore characteristics and trends of scientometric research authored by researchers in Taiwan based on journal articles and theses. The findings indicated that after the first article on scientometrics was published in 1987, an increasing trend was observed in the number of scientometric-related publications after 2000, indicating that scientometric research received more attention in recent years. The scope of disciplines of researchers was broad, and the number of disciplines continued to increase. This confirms the interdisciplinary nature of scientometric research with relationships that cross over different areas. From the perspective of the authors' disciplines, the largest percentage of the authors were from the fields of library and information science (LIS), followed by business and management, and medical science, but a considerable drop in number was observed in the percentage of LIS. In addition, co-authored articles were dominant. Over half of these articles were classified as inter-institutional collaboration and exhibited a steadily increasing trend. The number of interdisciplinary articles also exhibited an upward trend. Most of the research topics focused on citation analysis and characteristic of literature. The same trends were also found in the top two research methods: general bibliometric analysis and citation analysis. Due to the interdisciplinary nature of scientometric research, the academic backgrounds of the researchers would naturally be diverse. Given this characteristic, this study suggests that the relationship between disciplines of researchers and research topics can be further explored.