In fission reactors, neutron radiation is the main reason for the displacement of atoms in the crystalline lattice of the material. In this study, this damage is investigated on the fuel clad of the ...Bushehr reactor, which is Zr + 1%Nb. The MCNPX code is used to simulate the core of the reactor and find the highest neutron flux in the core of the reactor. Both the SRIM and SPECTER codes are used to study the neutron interaction with matter. The damage rate of the SRIM code is calculated in full cascade and quick damage modes, calculated as 2.05E−06 (dpa/s) and 1.06E−06 (dpa/s), respectively. Also, the damage rate in the SPECTER code is 1.0193E−06 (dpa/s), and the result has been compared with the SRIM code results. Using the calculated displacement per atom (dpa), the yield stress of the material, which is the resistance to the stresses, and the electrical resistivity of the material are calculated for 3 years of reactor operation. Both factors have increased over time, and the fuel clad lost its original function.
Leukocyte emigration is essential in both lymphocyte homing, as a central part of immune surveillance, and in leukocyte invasion at sites of inflammation. The emigration of leukocytes requires the ...interplay of adhesion molecules of the selectin and integrin families and chemokines. Selectindependent cell‐cell interaction is essential in localizing leukocytes within tissues by promoting the rolling of leukocytes along the endothelial cell surface before development of tight adhesion and subsequent transendothelial migration. Selectins also play an active role in the initiation of intracellular signaling pathways and regulation of cell‐cell interactions involving monocytes, lymphocytes, platelets, and endothelial cells. This review focuses mainly on the emerging evidence of biochemical signaling mechanisms involved in the regulation of selectin‐dependent leukocyte activation and adhesion, as well as the critical role played by selectins as leukocyte stimulatory molecules. This evidence has serious implications regarding the development of immune and inflammatory responses. This article will also review key structural features of the selectin receptors. A summary is provided of our current understanding of the specific molecular interaction occurring between these adhesion molecules and their counter‐receptors, focusing on the critical roles they may play in the regulation of functional responses. J. Leukoc. Biol. 63: 1–14; 1998.
Gastrotracheal fistula following open transhiatal esophagectomy (Orringer’s technique) for esophageal cancer is an unusual but lethal complication. Surgical intervention with resection of the fistula ...tract and primary interrupted suturing of gastric and tracheal orifices using a muscle flap interposition has proved to be a successful method. We report the case of a 73-year-old male with an adenocarcinoma of the distal part of the esophagus, who underwent open transhiatal esophagectomy (Orringer’s technique) with gastric tube reconstruction and cervical anastomosis. The patient did not receive induction chemoradiotherapy before the esophagectomy. Two attempts of surgical repair of fistula failed and the patient died. Being aware of warning signs such as dyspnea and respiratory distress accompanied by bilious content in the tracheal tube is helpful in the early detection and treatment of this type of fistula.
Introduction: Diabetes is associated with several debilitating complications, including the development of diabetic foot ulcers (DFUs), which can have serious consequences. This study emphasizes a ...multidisciplinary approach, providing a thorough overview of DFU pathogenesis and available treatments. Methods: An extensive literature review, covering studies published between 2000 and 2023, was conducted to gather data on DFU pathophysiology and treatments, including wound dressings, photobiomodulation, off-loading devices, adjunct medicines, and stem cell therapy. Results: DFUs are complicated due to infection, ischemia, and neuropathy. Sufficient wound dressings maintain a moist environment, promoting autolytic debridement and facilitating the healing process. Through cellular mechanisms, photobiomodulation therapy (PBM) was observed to expedite the healing process. Additionally, off-loading devices were invented to reduce ulcer pressure and promote healing. Adjunct therapies such as negative pressure wound therapy and hyperbaric oxygen therapy were identified as valuable tools for enhancing healing outcomes. Furthermore, autologous and allogeneic stem cell treatments exhibited the potential for promoting tissue regeneration and expediting the healing process. Conclusion: The complex pathophysiology of DFUs necessitates a multimodal treatment approach. Essential components include PBM, wound dressings, off-loading devices, adjunct treatments, and stem cell therapy.
This paper investigates the role of information technology in financial reporting as well as the relationship between using information technology and its impact on the quality of financial ...reporting. To identify the impact of information technology on quality of financial reporting, a questionnaire was designed and developed. In order to test the hypotheses, T-Test, ANOVA and Duncan's Test were employed. The results show that the information technology enhances the relevance and reduces the reliability of accounting information. It also increases comparability, albeit in a small amount, and diminishes the negative impact of dominant limitations on qualitative characteristics of accounting information. PUBLICATION ABSTRACT
A broadband THz absorber is presented which is based on frequency selective surfaces (FSS). In order to make the design tunable, graphene is used in the patch layer. Random hill climbing algorithm ...has been applied to find the optimum design corresponding to the broadest bandwidth. A 84% fractional bandwidth at low terahertzs is obtained by the optimum design.
The effect of selective cell activation through L-selectin and Mac-1 molecules cross-linking on neutrophil superoxide anion (O2-) generation and changes in intracellular calcium Ca2+i was ...investigated. Cross-linking of L-selectin using different mAbs induced a rapid and transient increase in Ca2+i and O2- generation by neutrophils that were dependent on the extent of L-selectin cross-linking and mAb epitope binding. In addition, cross-linking of L-selectin induced an up-regulation of surface Mac-1 expression on neutrophils. Cross-linking of Mac-1 molecules with mAb also induced significant changes in Ca2+i levels and O2- generation by neutrophils, which was also dependent on the epitope binding by mAb. Pretreatment of neutrophils with LPS caused a marked decrease in the expression of L-selectin molecules and significant inhibition (i.e., 59 +/- 4%) of anti-L-selectin mAb-dependent O2- generation and Ca2+i signal. In contrast, LPS pretreatment caused a significant up-regulation of Mac-1 molecules on neutrophil and enhanced O2- generation by neutrophils. The data indicate that cross-linking of L-selectin and Mac-1 initiates changes in Ca2+i and O2- production in neutrophils and suggest that these distinct adhesion molecules independently may play important regulatory roles in modulating neutrophil-endothelial cell interactions, transmigration, and neutrophil function at sites of tissue injury.
Chemotactic stimulation of neutrophils results in translocation of CD11b/CD18 (Mac-1) from intracellular storage pools to the cell surface. Though results from several laboratories indicate that the ...newly arrived surface Mac-1 is not involved in the adherence induced by the initial stimulus, the present study addresses the hypothesis that this Mac-1 plays a role in subsequent adherence-dependent functions. The response of human neutrophils to changing concentrations of a chemotactic stimulus was evaluated by determining the amount of newly arrived surface Mac-1, and Mac-1-dependent adhesion and locomotion. Small step-wise increases in the concentration of f-Met-Leu-Phe (FMLP) resulted in proportional stepwise increases in surface Mac-1 that plateaued within 2-4 min. This newly arrived Mac-1 supported adhesion to protein-coated surfaces only when the cells were exposed to an additional increase in the FMLP stimulus level. Adherence-dependent cellular locomotion was evaluated in chambers that allowed rapid changes in the stimulus concentration. Repeated small increments in the stimulus level at 200-s intervals resulted in significantly longer migration paths than a single-step increase in the stimulus. The results support the hypothesis that small increments in the chemotactic stimulus bring Mac-1 to the cell surface, and this newly mobilized Mac-1 is available for adherence-dependent locomotion with subsequent increases in the concentration of the stimulus.
Ovaj rad istražuje ulogu informacijske tehnologije u financijskom izvještavanju, kao i vezu između korištenja informacijske tehnologije i njezinog utjecaja na kvalitetu financijskog izvještavanja. ...Kako bi se prepoznao utjecaj informacijske tehnologije na kvalitetu financijskog izvještavanja, izrađen je i razvijen upitnik. Kako bi se testirale hipoteze, korišteni su T-test, ANOVA i Duncanov test. Rezultati pokazuju kako informacijska tehnologija dovodi do većeg značaja ali i do smanjene pouzdanosti računovodstvenih podataka. Također dovodi do povećane usporedivosti, iako u smanjenom opsegu, te ima za posljedicu smanjeni negativni utjecaj dominantnih ograničenja kvalitativnih obilježja računovodstvenih podataka.
Assessment of tissue viability following the application of a freezing protocol is challenging due to the paucity of viability assays that can be used dynamically, in situ. Cells transfected with a ...green fluorescent protein (GFP) vector actively produce GFP, which is retained intracellularly. Because of its constitutive and heritable expression, GFP fluorescence of transfected cells may have significant utility as a viability assay for cells within tissues. As a first step toward application to tissues, this work seeks to establish the validity of this GFP-based assay in cell suspensions by comparing the results to other accepted measures of viability. To the authors' knowledge, this is the first use of GFP in cryobiology applications. Intracellular GFP fluorescence was evaluated following slow freezing. Nontransfected and GFP-transfected rat 3230 adenocarcinoma (R3230AC) cells were frozen at 1°C/min to minimum temperatures between −5 and −30°C and then immediately thawed in a 37°C water bath. Samples were assayed using the common viability indicators trypan blue and ethidium bromide (EtBr). A regression analysis of recovery measured with the GFP assay as a function of recovery measured with a trypan blue assay gave a correlation coefficient of 0.97. A similar correlation coefficient, 0.95, was determined for recovery assessed by the GFP assay as a function of recovery measured by an EtBr assay. Nontransfected and GFP-transfected cells responded similarly to slow freezing, indicating that GFP transfection did not significantly alter the response of cells to typical freezing conditions. The excellent correlation of GFP assay results with those of two common viability assays suggests that the GFP-based assay is valid for cells and that further development of a tissue viability assay based on transfection is appropriate.
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