Prion infections of animals: safety of food and medicinal raw materials of animal origin. Up-to-date data

Prion infections of humans and animals are absolutely fatal. The cellular prion protein retains its antigenicity during the transition to the prion isoform; therefore, animals affected by prions do not respond to them with defensive reactions in the form of inflammation and the production of antibodies, which makes it difficult to diagnose the disease in vivo. In affected animals, prions accumulate in the nervous, lymphoreticular and muscle tissues and are released into the environment, in which they remain for many years. The resistance of prions to physical and chemical factors does not allow them to be inactivated in food by heat or radiation. Zoonoticity has been proven only for the causative agent of bovine spongiform encephalopathy, to which sheep, goats and pigs are susceptible. Sheep scrapie and chronic wasting deer disease occur widely in natural conditions in the form of enzootics and are similar in many characteristics. The zoonotic nature of their pathogens has not been proven.

Assessment of leaf morphological, physiological, chemical and stoichiometry functional traits for understanding the functioning of Himalayan temperate forest ecosystem

Leaf functional traits support plant survival and growth in different stress and disturbed conditions and respond according to leaf habit. The present study examined 13 leaf traits (3 morphological, 3 chemical, 5 physiological, and 2 stoichiometry) of nine dominant forest tree species (3 coniferous, 3 deciduous broad-leaved, 3 evergreen broad-leafed) to understand the varied response of leaf habits. The hypothesis was to test if functional traits of the conifers, deciduous and evergreen differ significantly in the temperate forest and to determine the applicability of leaf economic theory i.e., conservative vs. acquisitive resource investment, in the temperate Himalayan region. The attributes of the functional traits i.e., leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), leaf water content (LWC), stomatal conductance (Gs), and transpiration (E) followed the order deciduous > evergreen > coniferous. Leaf carbon and leaf C/N ratio showed the opposite pattern, coniferous > evergreen > deciduous. Chlorophyll (Chl) and photosynthetic rate (A) were highest for evergreen species, followed by deciduous and coniferous species. Also, structural equation modelling determined that morphological factors were negatively related to physiological and positively with chemical factors. Nevertheless, physiological and chemical factors were positively related to each other. The physiological traits were mainly regulated by stomatal conductance (Gs) however the morphological traits were determined by LDMC. Stoichiometry traits, such as leaf C/N, were found to be positively related to leaf carbon, and leaf N/P was found to be positively related to leaf nitrogen. The result of the leaf functional traits relationship would lead to precise prediction for the functionality of the temperate forest ecosystem at the regional scale.

The Effects of Some Physical and Chemical Factors on Apparent Resistivity of Surface Soil in the University of Mosul, Mosul City, Northern Iraq

Soil resistivity depends on many overlapping factors, which influence it in various ways. The aim of this study was to determine the effects of some physical and chemical factors on soil apparent resistivity. The results of field, laboratory, and statistical studies revealed a complex relationship between water content, pH, and salinity with soil apparent resistivity. The results showed that water content had a clear effect on apparent resistivity, as it increased significantly when water content value decreased to less than about 5%. The results also showed that increasing the salinity ratio at the expense of water content led to an increase in the apparent resistivity values. The apparent resistivity values also increased significantly when pH values ​​fell below about 7.7. The increase in air temperature caused an increase in water evaporation from the soil, which led to increasing the apparent resistivity. The rise in air temperature also caused an increase in the concentration of salts at the expense of water content; since salts are considered to be insulators, unless they are dissolved in water, they cause an increase in the value of apparent resistivity.

Phytoplankton in relation to physico-chemical factors in Poyang lake, Jiangxi

Changes of phytoplankton structure and water quality were investigated in Poyang Lake from March 2014 to December 2019.The number of identified species in Poyang Lake was 187 belonging to 87 genera and 8 phyla (excluding undetermined species). Among them, Cyanophyta (74 species) had the maximum number of species, followed by Bacillariophyta (51 species) and Chlorophyta (36 species). The average numbers of phytoplankton cells were counted 2783.85 ± 458.5×104 cells/l. A total of 20 dominant species were identified in Poyang Lake, including 6 of Cyanobacteria, 6 of Diatoms, 7 of Chlorophyta, 1 of Cryptophyta and 1 of Dinoflagellates. Among phytoplankton, Cyanophyta cell density was the highest, accounting for 91.06%. Chlorophyta and diatoms accounted for 5.52 and 2.09%, respectively. The cell density of Xanthophyta was the lowest, accounting for only 0.03%. The four seasons showed obvious changes, and the order was summer - autumn - spring - winter. Algae were the most common, including green algae 153 (53%), diatoms 74 (26%), cyanobacteria 17 (17%), similar to other domestic studies. Bangladesh J. Bot. 50(3): 855-863, 2021 (September) Special

Role of the Microenvironment in Mesenchymal Stem Cell-Based Strategies for Treating Human Liver Diseases

Liver disease is a severe health problem that endangers human health worldwide. Mesenchymal stem cell (MSC) therapy is a novel treatment for patients with different liver diseases due to its vast expansion potential and distinctive immunomodulatory properties. Despite several preclinical trials having confirmed the considerable efficacy of MSC therapy in liver diseases, the questionable safety and efficacy still limit its application. As a precursor cell, MSCs can adjust their characteristics in response to the surrounding microenvironment. The microenvironment provides physical and chemical factors essential for stem cell survival, proliferation, and differentiation. However, the mechanisms are still not completely understood. We, therefore, summarized the mechanisms underlying the MSC immune response, especially the interaction between MSCs and the liver microenvironment, discussing how to achieve better therapeutic effects.

Mycotoxins—Prevention, Detection, Impact on Animal Health

Mycotoxins are defined as secondary metabolites of some species of mold fungi. They are present in many foods consumed by animals. Moreover, they most often contaminate products of plant and animal origin. Fungi of genera Fusarium, Aspergillus, and Penicillum are most often responsible for the production of mycotoxins. They release toxic compounds that, when properly accumulated, can affect many aspects of breeding, such as reproduction and immunity, as well as the overall liver detoxification performance of animals. Mycotoxins, which are chemical compounds, are extremely difficult to remove due to their natural resistance to mechanical, thermal, and chemical factors. Modern methods of analysis allow the detection of the presence of mycotoxins and determine the level of contamination with them, both in raw materials and in foods. Various food processes that can affect mycotoxins include cleaning, grinding, brewing, cooking, baking, frying, flaking, and extrusion. Most feeding processes have a variable effect on mycotoxins, with those that use high temperatures having the greatest influence. Unfortunately, all these processes significantly reduce mycotoxin amounts, but they do not completely eliminate them. This article presents the risks associated with the presence of mycotoxins in foods and the methods of their detection and prevention.

Refining of Steel in Converters

In this chapter steelmaking processes and reactions are covered. A brief historical summary of important process developments is given and different types of converters are described. Then important chemical factors are detailed for the removal of the undesirable elements sulfur and phosphorus, and for the decarburization reactions. The refining of stainless steels in the argon oxygen decarburization (AOD) process is explained in detail, and a model for the AOD process is presented. Example simulations with the model illustrate how process changes may be introduced to improve productivity and reduce production costs.

Change in the coherence of light scattering from the surface of apples and their transpiration during storage

The potential possibility of using coherent optics for non-destructive testing to modify the microstructure of the surface of apples under the influence of chemical factors was studied. The model objects included solar and shade sides of fruits of Antonovka Common variety, untreated (control) and treated with diphenylamine (DPA). The amplitude-phase parameters of laser radiation reflected from the fruit surface were evaluated using a polarization shearing interferometer. It was experimentally shown that by the intensity and degree of coherence of the reflected laser radiation of the surface of apples, it is possible to register the anatomical and morphological characteristics of their tissues. It was revealed that after two months of storage, the spatial coherence of light scattering of the shadow side of an apple is higher than that of the solar, and the surface of apples treated with diphenylamine has a higher coherence of light scattering of the surface of both the solar and shadow sides. It was shown that the transpiration of apples treated with diphenylamine exceeds the transpiration of control apples.