The Potential for Temporary Stand-Off Pads Integrated With Poplar and Willow Silvopastoral Systems for Managing Nitrogen Leaching

Intensive pastoral farming has been linked to adverse environmental effects such as soil degradation and increased fluxes of nitrogen, phosphorus, sediments, and pathogens into waterways, resulting in their degradation. Stand-off pads are engineered structures covered with bedding materials, available for occupation by stock to minimise those adverse effects to soil and water bodies. Wood chips are ideal for bedding due to their low cost, high water holding capacity, and stock preference as resting areas. While they reduce the mobility of both nutrients and pathogens, their effectiveness depends on the type of wood, size of the chips, pH, pad design, and feeding management used. Dissolved organic carbon, present in wood residue, may slow nitrogen mineralisation thereby decreasing loss via leachate. This effect depends on plant tannins and nutrients already stored within the plant tissue. Poplar and willow have high concentrations of tannins in leaves and bark with potential nitrification-inhibiting properties. When grown on-farm, these deep-rooted trees also reduce nitrogen leaching and prevent soil erosion. This review addresses the use of temporary stand-off pads within poplar or willow silvopastoral systems. Harvested trees can provide suitable wood chips for constructing the stand-off pad, while the deep rooting systems of the trees will reduce the moisture content of the pad, preventing waterlogging. A key objective is to discuss the feasibility and establishment of multiple temporary stand-off pads that allow for stock rotation from pad to pad, and subsequent on-site composting of wood-wastes into fertiliser, reducing both nutrient inputs and losses in agricultural systems. The review highlights the potential suitability of poplar and willow tree species for such a system.

Odstraňování rtuti z kyselých roztoků chloridu rtuťnatého sorbenty připravenými katalyzovanou vulkanizací rostlinných olejů

Mercury is a metallic element, dangerous and toxic for the environment. Presently, the incineration of municipal solid waste (MSW) belongs to important sources of Hg emissions. Methods of conversion of metallic mercury and mercury compounds from soluble and toxic forms into water insoluble/non-toxic form (HgS) are sought after. Gaseous HCl and a significant part of HgCl2 vapors present in flue gas from incineration of MSW can be removed there by absorption in hot water. Efficiencies of Hg2+ removal from acidic water solutions by means of sorbents prepared by catalyzed reaction of sulfur with vegetable oils (inverse vulcanization) were studied. These kinds of sorbents were tested and found to be exploitable for selective removal of mercury ions from aqueous solutions, particularly from acidic solutions containing HCl at higher temperatures (50–75 °C). Presence of relatively high concentrations of salts of some other metallic elements (Fe, Zn, Ca) had only very small effects on Hg-sorption. Mercury adsorbed on such sorbents converts relatively quickly into a non-toxic form (HgS). Reactive sulfides and SH‑groups present on the surface of the sorbent particles contribute to a faster sorption of mercury and its conversion to HgS. Leaching of zinc from the catalyst (Zn‑diethyldithiocarbamate) present in the vulcanized sorbents is negligible at neutral conditions and small (about 10 %) at acidic conditions (pH = 1.5).

The Trypanosoma brucei-Derived Ketoacids, Indole Pyruvate and Hydroxyphenylpyruvate, Induce HO-1 Expression and Suppress Inflammatory Responses in Human Dendritic Cells

The extracellular parasite and causative agent of African sleeping sickness Trypanosoma brucei (T. brucei) has evolved a number of strategies to avoid immune detection in the host. One recently described mechanism involves the conversion of host-derived amino acids to aromatic ketoacids, which are detected at relatively high concentrations in the bloodstream of infected individuals. These ketoacids have been shown to directly suppress inflammatory responses in murine immune cells, as well as acting as potent inducers of the stress response enzyme, heme oxygenase 1 (HO-1), which has proven anti-inflammatory properties. The aim of this study was to investigate the immunomodulatory properties of the T. brucei-derived ketoacids in primary human immune cells and further examine their potential as a therapy for inflammatory diseases. We report that the T. brucei-derived ketoacids, indole pyruvate (IP) and hydroxyphenylpyruvate (HPP), induce HO-1 expression through Nrf2 activation in human dendritic cells (DC). They also limit DC maturation and suppress the production of pro-inflammatory cytokines, which, in turn, leads to a reduced capacity to differentiate adaptive CD4+ T cells. Furthermore, the ketoacids are capable of modulating DC cellular metabolism and suppressing the inflammatory profile of cells isolated from patients with inflammatory bowel disease. This study therefore not only provides further evidence of the immune-evasion mechanisms employed by T. brucei, but also supports further exploration of this new class of HO-1 inducers as potential therapeutics for the treatment of inflammatory conditions.

SAXS Reveals the Stabilization Effects of Modified Sugars on Model Proteins

Many proteins are usually not stable under different stresses, such as temperature and pH variations, mechanical stresses, high concentrations, and high saline contents, and their transport is always difficult, because they need to be maintained in a cold regime, which is costly and very challenging to achieve in remote areas of the world. For this reason, it is extremely important to find stabilizing agents that are able to preserve and protect proteins against denaturation. In the present work, we investigate, by extensively using synchrotron small-angle X-ray scattering experiments, the stabilization effect of five different sugar-derived compounds developed at ExtremoChem on two model proteins: myoglobin and insulin. The data analysis, based on a novel method that combines structural and thermodynamic features, has provided details about the physical-chemical processes that regulate the stability of these proteins in the presence of stabilizing compounds. The results clearly show that some modified sugars exert a greater stabilizing effect than others, being able to maintain the active forms of proteins at temperatures higher than those in which proteins, in the absence of stabilizers, reach denatured states.

Seven Years Study of the Seasonal Dynamics of Zooplankton Communities in a Large Subtropical Floodplain Ecosystem: A Test of the PEG Model

Irregular hydrological events, according to a classic plankton ecology group (PEG) study, can generate major deviations from the standard PEG model. However, little is known about the function of hydrological factors in influencing the seasonal dynamics of plankton. We used multivariate and Partial Least Squares Path Modeling to analyze the seasonal variation in crustacean zooplankton and related environmental factors from winter 2009 to winter 2016 in Lake Poyang, the largest freshwater lake in China. We found a distinct seasonal pattern in zooplankton development, which deviated, in part, from the PEG model, as we found indications of (1) a weaker degree of food limitation in winter and spring, likely due to high concentrations of allochthonous sources caused by decomposition of seasonally flooded hygrophytes, also affecting sediment dynamics; (2) a peak in crustacean zooplankton biomass in summer when the water level was high (and predation was lower), and where horizontal transport of zooplankton from the littoral zone to the pelagic was possibleand (3) a higher predation pressure in autumn, likely due to a shrinking water volume that left the fish concentrated in less water. The majority of these differences can be attributed to the direct or indirect impacts of physical factor variation.

Arsenic Accumulation and Biotransformation Affected by Nutrients (N and P) in Common Blooming-Forming Microcystis wesenbergii (Komárek) Komárek ex Komárek (Cyanobacteria)

Arsenic accumulation and biotransformation in algae was mostly carried out in a medium that contained far higher nutrient concentrations than that in natural freshwaters. The obtained results might have limited environmental validity and result in a failure to describe authentic arsenic biogeochemical cycles in natural freshwater systems. To validate the assumption, arsenic accumulation, and biotransformation in common bloom forming Microcystis wesenbergii was performed under a high nutrient concentration in BG11 medium (N = 250 mg/L, P = 7.13 mg/L), and adjusted low nutrients that mimicked values in natural freshwaters (N = 1.5 mg/L, P = 0.3 mg/L). The growth rate and maximum M. wesenbergii cell density were much lower in the high nutrient set, but more inhibition was shown with increasing ambient iAs(V) concentrations both in the high and low nutrient sets. The proportion of intracellular contents in total arsenicals decreased with increasing iAs(V) concentrations in both high and low nutrient sets but increased with incubation time. Intracellular iAs(III) was not found in the high nutrient set, while it formed high concentrations that could be comparable to that of an extracellular level in the low nutrient set. M. wesenbergii could methylate arsenic, and a higher proportion of organoarsenicals was formed in the low nutrient set. Lower intracellular MMA(V) and DMA(V) concentrations were found in the high nutrient set; contrarily, they presented a higher concentration that could be comparable to the extracellular ones in the low nutrient set. The results demonstrated that different nutrient regimes could affect arsenic accumulation and biotransformation in M. wesenbergii, and low nutrient concentrations could inhibit the excretion of iAs(III), MMA(V) and DMA(V) out of cells. Further investigations should be based on natural freshwater systems to obtain an authentic arsenic accumulation and biotransformation in cyanobacteria.

Environmental implications of fluoride presence in drinking water along the southeastern of El Bajío Guanajuatese, Guanajuato, Mexico: sources and health effects

Chronic exposure from drinking water with naturally high concentrations of fluoride (F⁻) has serious health consequences in several regions across the world including north-central Mexico as Guanajuato State, where the rural population is particularly dependent on untreated groundwater pumped from wells that have natural F- concentrations higher than those allowed by national and international regulations. The contaminated aquifers in the area are usually located in fractured volcanic environment that interacts with sedimentary basins and have a carbonate basement. Few studies focused on identifying the origin and hydrogeochemical processes related to fluoride release and mobilization have been developed, and even fewer that quantify the natural content of F in the geological environment. In this study, an evaluation of fluoride in volcanic rocks collected from 11 sampling sites along the Sierra de Codornices (Guanajuato State, Central Mexico) was carried out. The fluoride content is disseminated in volcanic rocks and the highest contents were obtained in felsic rocks. According to results obtained of a sampling campaign of 32 wells in 2019 their statistical and hydrogeochemical evaluation suggest that F- mobilization in groundwater from Juventino Rosas and Villagran municipalities, is a product of volcanic glass dissolution, a process involved in alkaline desorption occurring on the surfaces of F-containing minerals, and possibly on ion exchange occurring in minerals and some clays or even in deep fluids enriched in F. All these processes may be accelerated by the geothermal characteristics of the groundwater in the study area. The hydrogeochemical results and the epidemiological survey conducted indicate that children and older adults of Praderas de la Venta are at risk of exposure to F- due to the high concentrations ingested over a long period of time, to the toxicity of the element and its ability to accumulate in the bones. Prolonged exposure to high concentrations increases the risk.

Aroma Perception of Rose Oxide, Linalool and α-Terpineol Combinations in Gewürztraminer Wine

Cis-Rose oxide was found to be an important chiral compound in Gewürztraminer wine, with an enantiomeric ratio range from 76 to 58%. The enantiomeric ratio showed an important influence on white wine aroma when other monoterpenes were present. The aim of this study was to evaluate rose oxide at different ratios and changes to aroma perception, and the interaction of rose oxide with linalool and α-terpineol. A wine model was made based on Gewürztraminer wine. Twelve models were created with different ratios of rose oxide and concentrations of linalool and α-terpineol. Triangle tests, check-all-that-apply (CATA) and descriptive analysis were used to evaluate the aroma of the wines. Results show that the rose oxide ratios of 70:30 and 65:35 were statistically different. Additional descriptive analysis showed that the ratios altered aroma when linalool and α-terpineol were at low and medium concentrations. At high concentrations, linalool and α-terpineol masked any influence from rose oxide. Understanding how monoterpenes alter aroma perception of white wine when at different combinations and concentrations is important to achieving desired wine qualities and helps provide information on how flavor chemistry results can be interpreted without having to run sensory analysis.

The Effect of Chitosan Hydrolysate on Solanum Lycopersicum Plant Growth

Chitosan is a well-known subjectof researchbecause of its beneficial properties, including its antibacterial and fungicidal activity, as well as its effect on plant physiology. One of the maindifficulties in agricultural chitosan implementation is the poor solubility of high molecular chitosan in water. Reducing themolecular weight of chitosan by acid hydrolysis increases its solubility. This research studied the effect of chitosan hydrolysate on the germination and development ofSolanum lycopersicum L. plants. Theeffects of chitosan hydrolysate on seed germination, shoot development in the first week of development and in the first month of development were evaluated. According to the results, high concentrations of chitosan hydrolysate completely inhibited seed germination. However, short-term treatment by high concentrations of chitosan hydrolysate stimulatedthe development of seedlings, leading to substantially longerroots. Regular root application of high concentrations of chitosan hydrolysate inhibited plant development. Keywords: chitosan hydrolysate, chitosan, plant growth regulators, plant germination

Leakage of Endotoxins through the Endotoxin Retentive Filter: An in vitro Study

<b><i>Introduction:</i></b> Ultrapurification of dialysis fluid has enabled highly efficient dialysis treatments. Online hemodiafiltration is one such treatment that uses a purified dialysis fluid as a supplemental fluid. In this method, an endotoxin retentive filter (ETRF) is used in the final step of dialysis fluid purification, with the aim of preventing leakage of endotoxins. Sodium hypochlorite and peracetic acid are used as disinfecting agents for the dialysis fluid pipes containing the ETRF; however, the effects of these agents on ETRF membrane pores have not been fully clarified. <b><i>Methods:</i></b> Water permeability (flux) and endotoxin permeability were assessed in 3 types of ETRFs made with different membrane materials: polyester polymer alloy (PEPA), polyether sulfone (PES), and polysulfone (PS). High-concentration sodium hypochlorite and 2 types of peracetic acid were used as disinfecting agents, and the changes in flux and the endotoxin sieving coefficient (SC) were measured. <b><i>Results:</i></b> After repeated use of high concentrations of sodium hypochlorite and peracetic acid, the PEPA and PES ETRFs did not permit passage of endotoxins, regardless of their flux. However, in the PS ETRF, the flux and endotoxin SC increased with the number of cleaning cycles. No differences were observed according to the concentration of peracetic acid disinfecting agents. <b><i>Conclusion:</i></b> PEPA and PES ETRFs completely prevent endotoxin leakage and can be disinfected at concentrations higher than the conventionally recommended concentration without affecting pore expansion. Even new PS ETRFs have low levels of endotoxin leakage, which increase after disinfection cycles using sodium hypochlorite and peracetic acid.