Decolorization of textile dyes by laccases from a newly isolated strain of Trametes modesta

Four ligninolytic fungi, Trametes modesta, Trametes hirsuta, Trametes versicolor and Sclerotium rolfsii, were compared for their ability to produce laccases. The fungal laccases were screened for their ability to decolorize eight synthetic dyes (anthraquinone, azo, indigo and triarylmethane). The decolorization rate depended both on the source of the enzyme preparation and on the structure of the dye. Based on laccase production and dye decolorizing ability, T. modesta was selected for further studies. All the tested dyes were decolorized by the T. modesta laccase most efficiently under acid conditions (pH 3-6) but the optimum pH for decolorization of the individual dye varied. The decolorization rate of this laccase increased with the rise in temperature to 50-60 degrees C. The decolorization efficiency of T. modesta laccase was improved remarkably in the presence of mediators like 1-hydroxybenzotriazole and 2-methoxyphenothiazine.     

Opportune inward waste materials toward a zero waste ceramic slabs production in a circular economy perspective

This work is related to the preliminary lab-scale preparation of ceramic slabs, reproducing the characteristics of natural stones, containing up to more than 40 wt.% of different waste materials, namely laboratory glass, cullet glass (both thought as fluxing agents replacing feldspar), and ceramic waste obtained from drying squaring operations (for partial quartz sand replacement). Indeed, in order to pursue the circular economy principles, the possibility of turning different kinds of wastes into resources for the ceramic industry, surely represents the first concern to be addressed and demonstrated, with also the aim to reduce the environmental impact associated with landfill, minimizing manufacturing cost and contributing to preserve nonrenewable natural resources, which are known to be consistently depleted by the ceramic industries.     

Recycling of yttria‐stabilized zirconia waste powders in glazes suitable for ceramic tiles

The aim of this work is to demonstrate the feasibility of valorizing and recycling Yttria‐stabilized Zirconia thermal spray waste into high value products for industrial and residential use. Based on the powders chemistry and morphology, this work aims to realize products, like frits suitable for white glazes and ceramic tiles. The focus is on one class of powder: high‐temperature and abrasion‐resistant ceramics, like Yttria‐stabilized zirconia. This study has revealed that the substitution of pure zirconia with waste Yttria‐stabilized zirconia is possible in high percentages, up to 100% to prepare frits suitable for white glazes.     

Fragmentation of water on swift He ion impact

Charge exchange and fragmentation are the usual results in ion-molecule collision systems, and the specifics of the fragmentation process determine the chemical destiny of the target system. In this paper, we report recent progress on calculations of the fragmentation patterns for the model system He²⁺ + H₂O for projectile energies of a few keV. The calculations are obtained using the electron-nuclear dynamics (END) method for solution of the time-dependent Schrödinger equation.     

Female Mice with Selenocysteine tRNA Deletion in Agrp Neurons Maintain Leptin Sensitivity and Resist Weight Gain While on a High-Fat Diet

The role of the essential trace element selenium in hypothalamic physiology has begun to come to light over recent years. Selenium is used to synthesize a family of proteins participating in redox reactions called selenoproteins, which contain a selenocysteine residue in place of a cysteine. Past studies have shown that disrupted selenoprotein expression in the hypothalamus can adversely impact energy homeostasis. There is also evidence that selenium supports leptin signaling in the hypothalamus by maintaining proper redox balance. In this study, we generated mice with conditional knockout of the selenocysteine tRNA^[Ser]Sec gene (Trsp) in an orexigenic cell population called agouti-related peptide (Agrp)-positive neurons. We found that female Trsp^AgrpKO mice gain less weight while on a high-fat diet, which occurs due to changes in adipose tissue activity. Female Trsp^AgrpKO mice also retained hypothalamic sensitivity to leptin administration. Male mice were unaffected, however, highlighting the sexually dimorphic influence of selenium on neurobiology and energy homeostasis. These findings provide novel insight into the role of selenoproteins within a small yet heavily influential population of hypothalamic neurons.     

Anaerobic batch digestion of solid potato waste alone and in combination with sugar beet leaves

The objective of this study was to characterise anaerobic batch biodegradation of potato waste alone and when co-digested with sugar beet leaves. The effects of increasing concentration of potato waste expressed as percentage of total solids (TS) and the initial inoculum-to-substrate ratio (ISR) on methane yield and productivity were investigated. The ISRs studied were in the range 9.0–0.25 and increasing proportions of potato waste from 10% to 80% of TS. A maximum methane yield of 0.32 l CH₄/g VS_degraded was obtained at 40% of TS and an ISR of 1.5. A methane content of up to 84% was obtained at this proportion of potato waste and ISR. Higher ISRs led to faster onset of biogas production and higher methane productivity. Furthermore, co-digestion of potato waste and sugar beet leaves in varying proportions was investigated at constant TS. Co-digestion improved the accumulated methane production and improved the methane yield by 31–62% compared with digestion of potato waste alone.     

The work and energy theorem and the reciprocity relation in asymmetric magneto-elastodynamics

This paper deals with the extension of two classical theorems of linear elastodynamics, namely, the well-known work and energy theorem and Graffi's reciprocal relation, to unbounded electrically conducting elastic bodies moving in a magnetic field. The assumptions about the behaviour of solutions at large spatial distance (that seem unavoidable, because of the nonlinearity of the system governing the motion) seem to be as mild as possible.     

Measurement of saliva volume in the mouth of members of a trained sensory panel using a beetroot (Beta vulgaris) extract

The volume of saliva in the mouth of sensory panelists was measured by a dilution assay using a freshly prepared beetroot extract as probe solution. An aliquot of the extract absorbing linearly at 531-nm (probe) was placed in the mouth, mixed with saliva and returned to a clean container within a period of time shorter than the one spanning a single swallowing cycle. Beetroot pigments were neither partitioned into sub-fractions of saliva nor affected spectroscopically by their mixing with saliva. Three-milliliter was the minimum volume of probe per assay for a determination to be reliable. Observed volumes of saliva in the mouth of 13 panelists were distributed over the range 230–1310 μL with a median of 704 μL and a mean and standard deviation of 696 ± 312 μL. All but one of the subjects displayed salivary volumes within 1.41 standard deviations from the mean. Duplicate determinations per subject showed a median deviation of 13.5%. The procedure yielded highly repeatable and reproducible measurements.     

Comparative performance of a UASB reactor and an anaerobic packed-bed reactor when treating potato waste leachate

The results presented in this paper are from studies on a laboratory-scale upflow anaerobic sludge blanket (UASB) reactor and an anaerobic packed-bed (APB) reactor treating potato leachate at increasing organic loading rates from 1.5 to 7.0 g COD/1/day. The hydraulic retention times ranged from 13.2 to 2.8 days for both reactors during the 100 days of the experiment. The maximum organic loading rates possible in the laboratory-scale UASB and APB reactors for stable operation were approximately 6.1 and 4.7 g COD/l day, respectively. The COD removal efficiencies of both reactors were greater than 90% based on the total COD of the effluent. The methane yield increased with increasing organic loading rate up to 0.23 l CH₄/g COD_degraded in the UASB reactor and 0.161 CH₄/g COD_degraded in the APB reactor. The UASB could be run at a higher organic loading rate than the APB reactor and achieved a higher methane yield. Signs of reactor instability were decreasing partial alkalinity and pH and increasing amounts of volatile fatty acids. The study demonstrated the suitability of the UASB and a packed-bed reactor for treating leachate from potato waste.