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Numerous soil ecological functions are influenced by soil structure through its impact on spatial and temporal distributions of soil particles, water, and air within the soil profile. The nondestructive technique of x-ray computed tomography (CT) was used for studying soil structure. X-ray attenuation determined for two energy levels (80 kV and 120 kV) was used to calculate distribution of water, air, and solids, as well as the voxel dry bulk density for two silt loam subsoils. The spatial resolution during scanning was 0.25 mm in the horizontal and 1 mm in the vertical direction. For different voxel sizes, the weighted mean of the derived volumetric water, air, and solid contents, and the dry bulk densities agreed with the sample's phase composition and dry bulk density obtained by weighing. The use of dual energy scanning to study the heterogeneity of soil structure and the spatial distribution of water, air, and solids is discussed.

Antimony trisulfide (Sb 2 S 3 ) is an emerging semiconductor with a high absorption coefficient and a bandgap in the visible range. This makes it a promising material for various electronic and optoelectronic applications. However, one of the main challenges is still the synthesis of the material, as it is usually obtained either as a nanomaterial in its amorphous form with inferior optical properties or in crystalline rod-like structures in the micrometer or sub-micrometer range, which leads to application-related difficulties such as clogging in inkjet printing or spraying processes or highly porous layers in film applications. In this study, a one-pot synthesis of highly crystalline, spherical Sb 2 S 3 sub-micron particles is presented. The particles are growing encapsulated in a removable, wax-like matrix that is formed together with an intermediate from the precursors SbCl 3 and l-cysteine. Both substances are insoluble in the reaction mixture but well-dispersable in the solvent 1-octadecene (ODE). The intermediate forms a complex crosslinked architecture whose basic building block consists of an Sb atom attached to three cysteine molecules via Sb-S bonds. Embedded in the matrix consisting of excess cysteine, ODE, and chlorine, the intermediate decomposes into amorphous Sb 2 S 3 particles that crystallize as the reaction proceeds at 240 °C. The final particles are highly crystalline, spherical, and in the sub-micron range (420 ± 100 nm), making them ideal for further processing. The encapsulation method could not only provide a way to extend the size range of colloidal particles, but in the case of Sb 2 S 3 , this method circumvents the risk of carbonization of ligands or insufficient crystallization during the annealing of amorphous material., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Sb 2 S 3 is a promising nanomaterial for application in solar cells and in the fields of electronics and optoelectronics. Herein, Sb 2 S 3 nanoparticles were prepared via the hot-injection approach. In contrast to earlier work, the reaction temperature was decreased to 150 °C so that the reaction was slowed down and could be stopped at defined reaction stages. Thereby, the formation mechanism of the nanomaterial and the associated kinetics could be revealed. Based on morphological and structural analyses, it is suggested that seed particles (type 0) formed immediately after injecting the antimony precursor into the sulfur precursor. These seeds fused to form amorphous nanoparticles (type I) that contained a lower percentage of sulfur than that corresponding to the expected stoichiometric ratio of Sb 2 S 3 . The reason for this possibly lies in the formation of an oxygen- or carbon-containing intermediate during the seeding process. Afterward, the type I nanoparticles aggregated into larger amorphous nanoparticles (type II) in a second hierarchical assembly process and formed superordinate structures (type III). This process was followed by the crystallization of these particles and a layer-like growth of the crystalline particles by an Ostwald ripening process at the expense of the amorphous particles. It was demonstrated that the kinetic control of the reaction allowed tuning of the optical band gap of the amorphous nanoparticles in the range of 2.2-2.0 eV. On the contrary, the optical band gap of the crystalline particles decreased to a value of 1.7 eV and remained constant when the reaction progressed. Based on the proposed formation mechanism, future syntheses for Sb 2 S 3 particles can be developed, allowing tuning of the particle properties in a broad range. In this way, the selective use of this material in a wide range of applications will become possible., (Copyright © 2021, Joschko et al.)

Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.

Soil samples from several European countries were scanned using medical computer tomography (CT) device and are now available as CT images. The analysis of these samples was carried out using deep learning methods. For this purpose, a VGG16 network was trained with the CT images (X). For the annotation (y) a new method for automated annotation, 'surrogate' learning, was introduced. The generated neural networks (NNs) were subjected to a detailed analysis. Among other things, transfer learning was used to check whether the NN can also be trained to other y-values. Visually, the NN was verified using a gradient-based class activation mapping (grad-CAM) algorithm. These analyses showed that the NN was able to generalize, i.e. to capture the spatial structure of the soil sample. Possible applications of the models are discussed., (© 2021 The Authors.)

Soil organisms, including earthworms, are a key component of terrestrial ecosystems. However, little is known about their diversity, their distribution, and the threats affecting them. We compiled a global dataset of sampled earthworm communities from 6928 sites in 57 countries as a basis for predicting patterns in earthworm diversity, abundance, and biomass. We found that local species richness and abundance typically peaked at higher latitudes, displaying patterns opposite to those observed in aboveground organisms. However, high species dissimilarity across tropical locations may cause diversity across the entirety of the tropics to be higher than elsewhere. Climate variables were found to be more important in shaping earthworm communities than soil properties or habitat cover. These findings suggest that climate change may have serious implications for earthworm communities and for the functions they provide., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Background: Earthworms are important for maintaining soil ecosystem functioning and serve as indicators of soil fertility. However, detection of earthworms is time-consuming, which hinders the assessment of earthworm abundances with high sampling density over entire fields. Recent developments of mobile terrestrial sensor platforms for proximal soil sensing (PSS) provided new tools for collecting dense spatial information of soils using various sensing principles. Yet, the potential of PSS for assessing earthworm habitats is largely unexplored. This study investigates whether PSS data contribute to the spatial prediction of earthworm abundances in species distribution models of agricultural soils., Methodology/principal Findings: Proximal soil sensing data, e.g., soil electrical conductivity (EC), pH, and near infrared absorbance (NIR), were collected in real-time in a field with two management strategies (reduced tillage / conventional tillage) and sandy to loam soils. PSS was related to observations from a long-term (11 years) earthworm observation study conducted at 42 plots. Earthworms were sampled from 0.5 x 0.5 x 0.2 m³ soil blocks and identified to species level. Sensor data were highly correlated with earthworm abundances observed in reduced tillage but less correlated with earthworm abundances observed in conventional tillage. This may indicate that management influences the sensor-earthworm relationship. Generalized additive models and state-space models showed that modelling based on data fusion from EC, pH, and NIR sensors produced better results than modelling without sensor data or data from just a single sensor. Regarding the individual earthworm species, particular sensor combinations were more appropriate than others due to the different habitat requirements of the earthworms. Earthworm species with soil-specific habitat preferences were spatially predicted with higher accuracy by PSS than more ubiquitous species., Conclusions/significance: Our findings suggest that PSS contributes to the spatial modelling of earthworm abundances at field scale and that it will support species distribution modelling in the attempt to understand the soil-earthworm relationships in agroecosystems.

The purpose of the current study was to assess the validity of the Reynolds Intellectual Assessment Scale's (RIAS) index and subtest scores by examining whether the RIAS conforms to Carroll's ( 1993 ) three-stratum theory of cognitive ability and the Cattell-Horn Gf-Gc (Horn & Cattell, 1966 ) theory of intelligence upon which it was based. Factor structures of RIAS scores from typically developing (n = 187) and mixed clinical groups (n = 164), 4-18 years old, were compared using confirmatory factor analysis. The results were mixed, with some findings supporting the validity of the Composite Intelligence Index (CIX), Nonverbal Intelligence Index (NIX), and Verbal Intelligence Index (VIX) while others suggested that the CIX and NIX in particular should be interpreted with caution, depending on the population in which the RIAS is being used. The functioning of the two nonverbal subtests in all analyses suggested that the RIAS's nonverbal subtests are most problematic, with the greatest impact on the RIAS's validity as a measure of overall, verbal, and nonverbal intelligence. The RIAS's use as a general cognitive screener is supported but caution is recommended if the RIAS is being used to make important diagnostic, qualification for services, forensic, or placement decisions.

Neuropsychological tests are frequently used clinically to predict real-world, or adaptive functioning; however, there are too few data to support such predictions. The relationship between adaptive functioning and, in particular, attention tests, has not been documented. The present study sought to determine the association between several domains of attention and adaptive functioning in a heterogeneous clinical sample of 119 children. A significant omnibus canonical correlation (Rc=.54) indicated that attention and adaptive functioning are correlated even when controlling for intelligence. Tests of attention and adaptive functioning domains that give rise to the overall association are discussed in terms of their clinical utility.

The purpose of this study was to evaluate the construct validity of the Continuous Attention Test for Children (the CAT), a clinical measure of vigilance. To examine convergent and discriminant validity, a multitrait-multimethod matrix was used. It was predicted that the CAT would correlate with other neuropsychological measures involving vigilance, but not with measures involving potential confounds (e.g., short-term memory). Participants were 47 children, aged 6 to 11, referred for neuropsychological assessment. Results partially supported discriminant validity, but convergent validity was weak. That is, findings suggest that the CAT measures an ability distinct from those assessed by some other popular tests involving vigilance. However, method-related confounds may remain. The CAT appears to add useful information in the context of clinical evaluations.

We sought to determine whether Tourette syndrome (TS) was related to attentional disturbance independent of Attention Deficit Hyperactivity disorder (ADHD) and obsessive-compulsive symptoms (OCS), two comorbid conditions associated with attentional problems in other populations. Participants were 74 children [21 with uncomplicated TS (TS-Only), 14 with TS and ADHD (TS-ADHD), 21 with ADHD, and 18 controls]. Impaired sustained attention and impulsivity on a Continuous Performance Task were uncommon in the TS-Only group, but common in TS-ADHD and ADHD. The TS-ADHD group was less impulsive than the ADHD group, but had a higher rate of whole-body tics than the TS-Only group, raising questions about the diagnosis of ADHD in TS. OCS was not an independent risk factor for attention problems. However, the association of tic severity and impulsivity was consistent with the theory that TS involves dysfunction in cortical-subcortical circuits mediating behavioral inhibition.

Femtosecond mid-infrared laser pulses that are continuously tunable in the wavelength range from 9 to 18mum are demonstrated. These nearly bandwidth-limited pulses are generated by phase-matched difference-frequency mixing within the broad spectrum of 20-fs pulses from a mode-locked Ti:sapphire laser in GaSe. A direct determination of the pulse duration at 11.5mum gives a value of 140 fs. The average mid-infrared power of 1muW is ~100 times greater than that for infrared generation by non-phase-matched optical rectification.

Gemcitabine, a cytidine nucleoside analogue, has schedule-dependent antitumor activity in vitro and in vivo. Gemcitabine also has dose- and time-dependent radiosensitization properties in vitro. Thus it may have therapeutic application in combination with radiation. The aims of this study were to investigate whether gemcitabine could enhance radiation-induced tumor regrowth delay in a human squamous carcinoma (FaDu) xenograft in nude mice and to examine the effect of gemcitabine on radiation-induced apoptosis in in vivo tumors. Radiation was given locally to the tumors twice daily in 2 Gy fractions over 2 weeks for 5 days/week. Significant regrowth delay enhancement was observed which was dependent on gemcitabine schedule. Effective schedules using maximum tolerated gemcitabine doses were twice weekly and once weekly, but not daily. Significant toxicity occurred with radiation plus twice weekly gemcitabine, but enhancement was seen using gemcitabine doses well below the maximum tolerated dose. Both gemcitabine and radiation led to apoptotic cell death, but this was not increased when both treatments were combined. These results indicate that gemcitabine may be of therapeutic value as a radiation enhancer in the treatment of human cancers. Preliminary studies suggest that increased apoptotic cell death is not a mechanism leading to this enhancement.