Two-channel description of the rho meson and delta baryon

We describe the ? meson and Δ baryon in a coupled-channel formalism in which these hadrons are bound quark states in a closed channel and hadron scattering states in an open channel. We obtain good agreement with the known properties of the ? and Δ. Furthermore, we find that the coupling between channels produces substantial shifts in the calculated masses of the ? and Δ.     

A soluble-polymer system for the asymmetric transfer hydrogenation of ketones

The appropriate combination of methacrylate polymers permits the synthesis of a soluble polymer for use in ruthenium(II)-catalyzed asymmetric transfer hydrogenation reactions. Using a 7:3 copolymer of a poly(ethylene glycol) ester and a hydroxyethyl ester, a derived ruthenium(II)/norephedrine complex catalyses reduction of acetophenone in up to 95% yield and 81% ee.     

Testing static quark-antiquark potentials with bottomonium

We investigate the question of whether experimental data on the energy levels of bottomonium can discriminate between quark-antiquark potentials which are motivated by what we know about QCD and potentials which are purely phenomenological. We restrict ourselves to bottomonium because, of all the quarkonia observed thus far, bottomonium is the least relativistic and therefore the best testing ground for the static quarkonium potential. We consider two potentials whose functional form is motivated from perturbative QCD at short quark-antiquark separations and from nonperturbative lattice QCD at large separations. We also consider three strictly phenomenological potentials. We find that the best of the three phenomenological potentials, which has never been previously used, fits the spin-averaged data at least as well as the best of the QCD-motivated potentials. We propose further measurements on bottomonium energy levels to provide additional tests.     

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Ohne Zusammenfassung Hugo Hadwiger zum 65. Geburtstag gewidmet     

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Ohne Zusammenfassung     

Magnetic ordering in the spin-ice candidate Ho2Ru2O7

Neutron scattering measurements on the spin-ice candidate material Ho2Ru2O7 have revealed two magnetic transitions at T approximately 95 and approximately 1.4 K to long-range ordered states involving the Ru and Ho sublattices, respectively. Between these transitions, the Ho3+ moments form short-ranged ordered spin clusters. The internal field provided by the ordered S=1 Ru4+ moments disrupts the fragile spin-ice state and drives the Ho3+ moments to order. We have directly measured a slight shift in the Ho3+ crystal field levels at 95 K from the Ru ordering.     

Relation of Spatial Skills to Calculus Proficiency: A Brief Report

Spatial skills have been shown in various longitudinal studies to be related to multiple science, technology, engineering, and math (STEM) achievement and retention. The specific nature of this relation has been probed in only a few domains, and has rarely been investigated for calculus, a critical topic in preparing students for and in STEM majors and careers. We gathered data on paper-and-pencil measures of spatial skills (mental rotation, paper folding, and hidden figures); calculus proficiency (conceptual knowledge and released Advanced Placement [AP] calculus items); coordinating graph, table, and algebraic representations (coordinating multiple representations); and basic graph/table skills. Regression analyses suggest that mental rotation is the best of the spatial predictors for scores on released AP calculus exam questions (β = 0.21), but that spatial skills are not a significant predictor of calculus conceptual knowledge. Proficiency in coordinating multiple representations is also a significant predictor of both released AP calculus questions (β = 0.37) and calculus conceptual knowledge (β = 0.47). The spatial skills tapped by the measure for mental rotation may be similar to those required to engage in mental animation of typical explanations in AP textbooks and in AP class teaching as tested on the AP exam questions. Our measure for calculus conceptual knowledge, by contrast, did not require coordinating representations.     

A Raman spectroscopic study of synthetic giniite

The mineral giniite has been synthesised and characterised by XRD, SEM and Raman and infrared spectroscopy. SEM images of the olive-green giniite display a very unusual image of pseudo-spheres with roughened surfaces of around 1-10microm in size. The face to face contact of the spheres suggests that the spheres are colloidal and carry a surface charge. Raman spectroscopy proves the (PO4)3- units are reduced in symmetry and in all probability more than one type of phosphate unit is found in the structure. Raman bands at 77K are observed at 3380 and 3186cm-1 with an additional sharp band at 3100cm-1. The first two bands are assigned to water stretching vibrations and the latter to an OH stretching band. Intense Raman bands observed at 396, 346 and 234cm-1are attributed to the FeO stretching vibrations. The giniite phosphate units are characterised by two Raman bands at 1023 and 948cm-1 assigned to symmetric stretching mode of the (PO4)3- units. A complex band is observed at 460.5cm-1 with additional components at 486.8 and 445.7cm-1 attributed to the nu(2) bending modes suggesting a reduction of symmetry of the (PO4)3- units.     

Post-Harvest Operations to Generate High-Quality Medicinal Cannabis Products: A Systemic Review

The traditional Cannabis plant as a medicinal crop has been explored for many thousands of years. The Cannabis industry is rapidly growing; therefore, optimising drying methods and producing high-quality medical products have been a hot topic in recent years. We systemically analysed the current literature and drew a critical summary of the drying methods implemented thus far to preserve the quality of bioactive compounds from medicinal Cannabis. Different drying techniques have been one of the focal points during the post-harvesting operations, as drying preserves these Cannabis products with increased shelf life. We followed or even highlighted the most popular methods used. Drying methods have advanced from traditional hot air and oven drying methods to microwave-assisted hot air drying or freeze-drying. In this review, traditional and modern drying technologies are reviewed. Each technology will have different pros and cons of its own. Moreover, this review outlines the quality of the Cannabis plant component harvested plays a major role in drying efficiency and preserving the chemical constituents. The emergence of medical Cannabis, and cannabinoid research requires optimal post-harvesting processes for different Cannabis strains. We proposed the most suitable method for drying medicinal Cannabis to produce consistent, reliable and potent medicinal Cannabis. In addition, drying temperature, rate of drying, mode and storage conditions after drying influenced the Cannabis component retention and quality.     

Monitoring Compositional Changes in Black Soldier Fly Larvae (BSFL) Sourced from Different Waste Stream Diets Using Attenuated Total Reflectance Mid Infrared Spectroscopy and Chemometrics

Black soldier fly (Hermetia illucens, L.) larvae are characterized by their ability to convert a variety of organic matter from food waste into a sustainable source of food (e.g., protein). This study aimed to evaluate the use of attenuated total reflectance (ATR) mid-infrared (MIR) spectroscopy to monitor changes in the composition as well as to classify black soldier fly larvae (BSFL) samples collected from two growth stages (fifth and sixth instar) and two waste stream diets (bread and vegetables, soy waste). The BSFL samples were fed on either a soy or bread-vegetable mix waste in a control environment (temperature 25 °C, and humidity 70%). The frass and BSFL samples harvested as fifth and sixth instar samples were analyzed using an ATR-MIR instrument where frequencies at specific wavenumbers were compared and evaluated using different chemometric techniques. The PLS regression models yield a coefficient of determination in cross-validation (R²) > 0.80 for the prediction of the type of waste used as diet. The results of this study also indicated that the ratio between the absorbances corresponding to the amide group (1635 cm⁻¹) and lipids (2921 + 2849 cm⁻¹) region was higher in diets containing a high proportion of carbohydrates (e.g., bread-vegetable mix) compared with the soy waste diet. This study demonstrated the ability of MIR spectroscopy to classify BSFL instar samples according to the type of waste stream used as a diet. Overall, ATR-MIR spectroscopy has shown potential to be used as tool to evaluate and monitor the development and growth of BSFL. The utilization of MIR spectroscopy will allow for the development of traceability systems for BSFL. These tools will aid in risk evaluation and the identification of hazards associated with the process, thereby assisting in improving the safety and quality of BSFL intended to be used by the animal feed industry.