Effectiveness of Aluminum Sulfate and Ethylenediamine Tetraacetic Acid as Carbohydrate Protectors during Oxygen Delignification

Objective The purpose of this thesis will be to examine three carbohydrate protector\u27s effectiveness during oxygen delignification. Today, about half of the lignin can be removed from a conventional kraft pulp through the application of oxygen delignification as an initial stage in the bleaching process. More extensive delignification results in the degradation of pulp carbohydrates, influencing the final pulp qualities.1 Carbohydrates are attacked by the decomposition of hydroperoxides catalyzed by heavy metal ions, free radicals. Carbohydrate protectors function to deactivate the free radicals, reducing the rate of attack on the carbohydrates.2 This thesis is based on the above principle. The carbohydrate protectors for comparison are thylenediamine Tetraacetic Acid (EDTA). Aluminum Sulfate [Al (2SO4)3] and Magnesium Sulfate [Mg2SO4]

Перспективы использования термофильного режима в биогазовой технологии по переработке отходов сельского хозяйства

В данной статье рассматриваются биогазовые установки для переработки отходов сельского хозяйства и описываются базовые элементы их различных конструкций. Кроме того, рассматриваются режимы биогазовой технологии, из которых оптимальным и перспективным для Томской области является термофильный режим, который позволяет снизить капитальные затраты на производство биогазовой установки, снизить энергетические затраты на подогрев и поддержание температуры субстрата установки и получить экологически чистые биоудобрения и биогаз. This article looks at biogas plants for processing agricultural waste and outlines the basic elements of various designs. It also covers modes of biogas technology, from which the best and promising for the Tomsk region is thermophilic mode, which reduces the capital expenditure on the biogas plant, to reduce energy costs for heating and maintenance of the installation of the substrate temperature and obtain eco-friendly bio-fertilizer and biogas

Tissue remodeling macrophages morphologically dominate at the interface of polypropylene surgical meshes in the human abdomen

Background Mesh implants are widely used to reinforce the abdominal wall, although the inevitable inflammatory foreign body reaction (FBR) at the interface leads to complications. Macrophages are suspected to regulate the subsequent scar formation, but it is still unclear whether adequate fibrous scar formation with collagen deposition depends mainly on the presence of M1 or M2 macrophages. Methods This study investigated the FBR to seven human polypropylene meshes, which were removed after a median incorporation time of 1 year due to the primary complaint of recurrence. Using immunofluorescence, the FBR was examined in six regional zones with increasing distance from the mesh fibers up to 350 µm, based on the cell densities, macrophage M1 (CD86) and M2 (CD163, CD206) phenotypes, deposition of collagen-I and -III, and expression of matrix metalloproteinase-2 (MMP-2) and -8 as indicator of collagen degradation. Results All mesh–tissue complexes demonstrated a decrease in cell density and macrophages with distance to the mesh fibers. Overall, about 60% of the macrophages presented an M2 phenotype, whereas only 6% an M1 phenotype. Over 70% of macrophages showed co-expression with collagen-I or -III and over 50% with MMP-2. Conclusions The chronic FBR to polypropylene meshes is associated with an M2 macrophage response, which is accompanied by collagen deposition and MMP-2 expression. These findings challenge the idea that mainly M1 macrophages are related to inflammation and highlights that iatrogenic attempts to polarize these cells towards the M2 phenotype may not be a solution to ameliorate the long-term foreign body reaction

Shared Active Site Architecture between the Large Subunit of Eukaryotic Primase and DNA Photolyase

DNA synthesis during replication relies on RNA primers synthesised by the primase, a specialised DNA-dependent RNA polymerase that can initiate nucleic acid synthesis de novo. In archaeal and eukaryotic organisms, the primase is a heterodimeric enzyme resulting from the constitutive association of a small (PriS) and large (PriL) subunit. The ability of the primase to initiate synthesis of an RNA primer depends on a conserved Fe-S domain at the C-terminus of PriL (PriL-CTD). However, the critical role of the PriL-CTD in the catalytic mechanism of initiation is not understood.Here we report the crystal structure of the yeast PriL-CTD at 1.55 A resolution. The structure reveals that the PriL-CTD folds in two largely independent alpha-helical domains joined at their interface by a [4Fe-4S] cluster. The larger N-terminal domain represents the most conserved portion of the PriL-CTD, whereas the smaller C-terminal domain is largely absent in archaeal PriL. Unexpectedly, the N-terminal domain reveals a striking structural similarity with the active site region of the DNA photolyase/cryptochrome family of flavoproteins. The region of similarity includes PriL-CTD residues that are known to be essential for initiation of RNA primer synthesis by the primase.Our study reports the first crystallographic model of the conserved Fe-S domain of the archaeal/eukaryotic primase. The structural comparison with a cryptochrome protein bound to flavin adenine dinucleotide and single-stranded DNA provides important insight into the mechanism of RNA primer synthesis by the primase

Age-dependent resistance to Porcine reproductive and respiratory syndrome virus replication in swine

<p>Abstract</p> <p>Background</p> <p>Porcine reproductive and respiratory syndrome virus (PRRSV) causes a prolonged, economically devastating infection in pigs, and immune resistance to infection appears variable. Since the porcine adaptive immune system is not fully competent at birth, we hypothesized that age influences the dynamics of PRRSV infection. Thus, young piglets, growing 16-20-week-old finisher pigs, and mature third parity sows were infected with virulent or attenuated PRRSV, and the dynamics of viral infection, disease, and immune response were monitored over time.</p> <p>Results</p> <p>Virulent PRRSV infection and disease were markedly more severe and prolonged in young piglets than in finishers or sows. Attenuated PRRSV in piglets also produced a prolonged viremia that was delayed and reduced in magnitude, and in finishers and sows, about half the animals showed no viremia. Despite marked differences in infection, antibody responses were observed in all animals irrespective of age, with older pigs tending to seroconvert sooner and achieve higher antibody levels than 3-week-old animals. Interferon γ (IFN γ) secreting peripheral blood mononuclear cells were more abundant in sows but not specifically increased by PRRSV infection in any age group, and interleukin-10 (IL-10) levels in blood were not correlated with PRRSV infection status.</p> <p>Conclusion</p> <p>These findings show that animal age, perhaps due to increased innate immune resistance, strongly influences the outcome of acute PRRSV infection, whereas an antibody response is triggered at a low threshold of infection that is independent of age. Prolonged infection was not due to IL-10-mediated immunosuppression, and PRRSV did not elicit a specific IFN γ response, especially in non-adult animals. Equivalent antibody responses were elicited in response to virulent and attenuated viruses, indicating that the antigenic mass necessary for an immune response is produced at a low level of infection, and is not predicted by viremic status. Thus, viral replication was occurring in lung or lymphoid tissues even though viremia was not always observed.</p

Использование метода моделирования ситуаций при обучении студентов вуза английскому языку

В статье описывается опыт проведения занятий по английскому языку у студентов второго курса направления "Горное дело" с использованием современного активного метода обучения case study. Отмечаются преимущества применения технологии моделирования ситуации при преподавании профессионально-ориентированного курса английского языка в вузе

Characterization of innate and adaptive immune cells involved in the foreign body reaction to polypropylene meshes in the human abdomen

Background Polypropylene (PP) mesh is widely used to reinforce tissues. The foreign body reaction (FBR) to the implant is dominated by innate immune cells, especially macrophages. However, considerable numbers of adaptive immune cells, namely T cells, have also been regularly observed, which appear to play a crucial role in the long-term host response. Methods This study investigated the FBR to seven human PP meshes, which were removed from the abdomen for recurrence after a median of one year. Using immunofluorescence microscopy, the FBR was examined for various innate (CD11b+ myeloid, CD68+ macrophages, CD56+ NK) and adaptive immune cells (CD3+ T, CD4+ T-helper, CD8+ cytotoxic, FoxP3+ T-regulatory, CD20+ B) as well as “conventional” immune cells (defined as cells expressing their specific immune cell marker without co-expressing CD68). Results T-helper cells (19%) and regulatory T-cells (25%) were present at comparable rates to macrophages, and clustered significantly toward the mesh fibers. For all cell types the lowest proportions of “conventional” cells (< 60%) were observed at the mesh–tissue interface, but increased considerably at about 50–100 µm, indicating reduced stimulation with rising distance to the mesh fibers. Conclusion Both innate and adaptive immune cells participate in the chronic FBR to PP meshes with T cells and macrophages being the predominant cell types, respectively. In concordance with the previous data, many cells presented a “hybrid” pattern near the mesh fibers. The complexity of the immune reaction seen within the foreign body granuloma may explain why approaches focusing on specific cell types have not been very successful in reducing the chronic FBR

The impact of unscheduled gaps and iso-centre sequencing on the biologically effective dose in Gamma Knife radiosurgery.

PURPOSE: Establish the impact of iso-centre sequencing and unscheduled gaps in Gamma Knife® (GK) radiosurgery on the biologically effective dose (BED). METHODS: A BED model was used to study BED values on the prescription iso-surface of patients treated with GK Perfexion™ (Vestibular Schwannoma). The effect of a 15 min gap, simulated at varying points in the treatment delivery, and adjustments to the sequencing of iso-centre delivery, based on average dose-rate, was quantified in terms of the impact on BED. RESULTS: Depending on the position of the gap and the average dose-rate profiles, the mean BED values were decreased by 0.1% to 9.9% of the value in the original plan. A heuristic approach to iso-centre sequencing showed variations in BED of up to 14.2%, relative to the mean BED of the original sequence. CONCLUSIONS: The treatment variables, like the iso-centre sequence and unscheduled gaps, should be considered during GK radiosurgery treatments

The relation between general diseases and periodontal diseases in hospitalised subjects

Abstract no. 1755published_or_final_versio