Uranium Superconductivity Redux

Since the discovery of heavy-fermion superconductivity in uranium compounds in the early 1980s, other uranium compounds have been discovered that are fully as interesting to study. However, as we look forward in the year 2000, we now have higher-purity, single crystals of the element itself. Preliminary resistivity and ac susceptibility measurements show the improved quality of the samples and thus hold the promise of understanding many aspects of its superconductivity, which have remained untouched for almost 25 years.     

Theophylline: Old Drug in a New Light,Application in COVID-19 through Computational Studies

Theophylline (3-methyxanthine) is a historically prominent drug used to treat respiratory diseases, alone or in combination with other drugs. The rapid onset of the COVID-19 pandemic urged the development of effective pharmacological treatments to directly attack the development of new variants of the SARS-CoV-2 virus and possess a therapeutical battery of compounds that could improve the current management of the disease worldwide. In this context, theophylline, through bronchodilatory, immunomodulatory, and potentially antiviral mechanisms, is an interesting proposal as an adjuvant in the treatment of COVID-19 patients. Nevertheless, it is essential to understand how this compound could behave against such a disease, not only at a pharmacodynamic but also at a pharmacokinetic level. In this sense, the quickest approach in drug discovery is through different computational methods, either from network pharmacology or from quantitative systems pharmacology approaches. In the present review, we explore the possibility of using theophylline in the treatment of COVID-19 patients since it seems to be a relevant candidate by aiming at several immunological targets involved in the pathophysiology of the disease. Theophylline down-regulates the inflammatory processes activated by SARS-CoV-2 through various mechanisms, and herein, they are discussed by reviewing computational simulation studies and their different applications and effects.     

Rheological properties and stability of model salad dressing emulsions prepared with a dry-heated soybean protein isolate–dextran mixture

The rheological characteristics of model salad dressing emulsions, incorporating a dry-heated soybean protein isolate (SPI)–dextran mixture as emulsifier, were investigated by applying dynamic rheometry tests in an attempt to probe the emulsion structure and to elucidate the mechanism of their stability against creaming. Both the viscoelastic properties and the creaming behaviour of the dressings were greatly influenced by the extent of protein–dextran conjugation and also by xanthan gum addition. The results are discussed in terms of emulsion droplet interactions which, depending on the extent of glyco-conjugation, may be dominated by depletion or ‘bridging’ flocculation effects and, thereby, influence the droplet network structure collapse during ageing.     

Chromium remediation or release? Effect of iron(II) sulfate addition on chromium(VI) leaching from columns of chromite ore processing residue

Chromite ore processing residue (COPR), derived from the so-called high lime processing of chromite ore, contains high levels of Cr(III) and Cr(VI) and has a pH between 11 and 12. Ferrous sulfate, which is used for remediation of Cr(VI) contamination in wastewater and soils via reduction to Cr(III) and subsequent precipitation of iron(III)/chromium(III) hydroxide, has also been proposed for remediation of Cr(VI) in COPR. Instead, however, addition of FeSO4 to the infiltrating solution in column experiments with COPR greatly increased leaching of Cr(VI). Leached Cr(VI) increased from 3.8 to 12.3 mmol kg(-1) COPR in 25 pore volumes with 20 mM FeSO4, reaching solution concentrations as high as 1.6 mM. Fe(II) was ineffective in reducing Cr(VI) to Cr(III) because it precipitated when it entered the column due to the high pH of COPR, while Cr(VI) in solution was transported away with the infiltrating solution. The large increase in leaching of Cr(VI) upon infiltration of sulfate, either as FeSO4 or Na2SO4, was caused by anion exchange of sulfate for chromate in the layered double hydroxide mineral hydrocalumite, a process for which scanning electron microscopy with energy-dispersive X-ray microanalysis provided direct evidence.     

The composition of a gel formed when wheat flour is suspended in phenol-acetic acid-water (1:1:1, w/v/v)

A gel which formed when wheat flour was suspended in phenol-acetic acid-water (1:1:1, w/v/v/) was fractionated into a protein-rich soluble fraction and a carbohydrate-rich insoluble fraction. Gel electrophoresis showed that the soluble fraction contained several proteins and had an amino acid composition with a high content of proline and glutamyl residues and a low content of lysine. The soluble fraction also contained lipids which were mainly phospholipids, phospholipid derivatives and glycolipids and other compounds, which yielded galactose and glucose after acid hydrolysis. The insoluble fraction contained a polysaccharide with similar properties to starch, and lipids which were mainly neutral fats, sterols and sterol esters. Both fractions contained arabinoxylans and mannans. The gel did not contain any nucleic acids. The protein-rich soluble fractions of gels prepared from other wheat flours and air-classified flour fractions, from wheat gluten and from rye and barley flours, showed marked differences in amino acid composition. It is concluded that a heterogeneous class of proteins, rather than specific proteins in fixed proportions, is involved in gel formation.     

Effect of organic production system on broiler carcass and meat quality

The effect of organic production on broiler carcass and meat quality was assessed. Two hundred and fifty Ross male chickens were assigned to two different systems of production: conventional, housing in an indoor pen (0.12 m(2)/bird); organic, housing in an indoor pen (0.12 m(2)/bird) with access to a grass paddock (4 m(2)/bird). At 56 and 81 days of age, 20 chickens per group were slaughtered to evaluate carcass traits and the characteristics of breast and drumstick muscles (m. pectoralis major and m. peroneus longus). The organic chickens had carcasses with a higher breast and drumstick percentages and lower levels of abdominal fat. The muscles had lower pHu and water holding capacity. Instead cooking loss, lightness values, shear values, Fe, polyunsaturated fatty acids of n-3 series and TBA-RS were higher. The sensory quality of the breast muscle was better. Organic production system seems to be a good alternative method, due to better welfare conditions and good quality of the carcass and meat. A negative aspect was the higher level of TBA-RS in the muscles, probably due to greater physical activity.