50 research outputs found
The stability and gravitational Newtonian limit of a modified Randall-Sundrum model
For a modified Randall-Sundrum model [Phys. Rev. D 88 (2013) 025048], the
graviton equations are derived and the mass spectrum found. The latter includes
a massless graviton and a continuum mass with a gap. There is no negative
mass-squared in the spectrum, so the model is stable. The gravitational
Newtonian limit is obtained with an exponentially suppressed modification from
extra dimension.Comment: 10 page
Cardiovascular tissue engineering and regeneration based on adipose tissue-derived stem/stromal cells
Currently, the pre-clinical field is rapidly progressing in search of new therapeutic modalities that replace or complement current medication to treat cardiovascular disease. Among these are the single or combined use of stem cells, biomaterials and instructive factors, which together form the triad of tissue engineering and regenerative medicine. Stem cell therapy is a promising approach for repair, remodeling and even regenerate tissue of otherwise irreparable damage, such as after myocardial infarction (aMI) and Aortic aneurysm. A severe limitation of cardiac stem cell therapy is the generally poor retention of administered cells in the target tissue. In tissue repair, the main mode of action of adipose tissue-derived stem cells (ADSC) is the production of various growth factors, cytokines, anti-inflammatory and anti-apoptotic factors that together augment repair, remodeling and regeneration. In this thesis, we have shown that the topography and (bio) chemistry of the biomaterial have an impact on the ADSC biological behavior
The assessment of the relationship between performance audits on public accountability in Iran
The purpose of this research is the assessment of the relationship between performance audits accountability on the point of view of Supreme Audit Court's auditors. In this research, the statistical society includes 1072 individuals taken from Audit Court Supreme's official technical experts. In the present study, 330 individuals have been chosen as sample through random sampling. T-test and Freidman Correlation test are used for analyzing data. The results show a confirmation of a direct relationship between audit performances on public accountability. Moreover, the use of performance audit leads to an increase in clarity, quality and the qualitative characteristics of information and finally to an upgrade in accountability of the government in its actions' performance. Keywords: performance audit; accountability; Iran's Supreme Audit Court; clarity
Impact of intermediate volumes and cell diameters on cell recovery: A predictive model for autologous immunotherapy workflows
CAR-T immunotherapy workflows can vary from process to process and customer to customer. Variables that can alter overall processing efficiency include cell type, cell diameter, input cell numbers, input volumes, final volumes, and number of rinses, among others. These process-specific differences can make it difficult to estimate outputs, and equally challenging to select which processing parameters to use for which workflow. We hypothesized that intermediate processing volumes might vary as the size of the cell diameter increases, to accommodate the larger pellet created during centrifugation and other processing steps. From this, we developed a mathematical model and designed a study to test the validity of our hypothesis. Testing involved using Sepax™ C-Pro CultureWash v432 software to assess the calculated intermediate volume as a function of cell diameter by looking at percent recovery of the harvest. As shown in Equation 1 below, we predict the minimum intermediate volume required for the total number of cells to be function of cell size, total cell number, and an additional 20% buffer volume. Recoveries exceed 88% on a linear range up to 4 billion cells that are ~16 µm in size, where the formula holds true. While recoveries dropped to 68% for larger cell harvests, with a more optimized parameter set (e.g., altered flow rates), we rescued 86% on average for 6 billion cells. In summary, the model and associated data developed on the Sepax™ C-Pro around intermediate volumes provides a framework for future decision-making as scientists develop and adapt workflows to serve novel immunotherapy applications. Future work will address other variables of interest such as additional cell types, pump speed, and larger input cell numbers.
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Beeswax-colophony blend: a novel green organic coating for protection of steel drinking water storage tanks
Beeswax-colophony blend is mainly used as a sealant mixture for preservation applications. The beeswax itself, however, has had a long way in history taking part in conservation processes including mummification. In this research, this blend was used as a protective coating for drinking water distribution tanks. Initially, a layer with 400 μm thickness was applied on a sand blasted mild steel plate. The long-term electrochemical behavior of the coating was investigated by open circuit potential (OCP) and electrochemical microbiological characteristics of the coating, microbial and chemical examinations were performed on drinking water samples that had been in contact with the coating. Furthermore, its behavior in an up-flow anaerobic sludge blanket reactor (UASBR) in a wastewater treatment plant was investigated using the scanning electron microscopy (SEM) technique. Regarding the consistency of experimental results, it was concluded that this proposed recyclable blend could be considered as a novel green organic coating and also a good corrosion barrier even in aggressive environments
The anti-inflammatory function of HDL is impaired in type 2 diabetes:Role of hyperglycemia, paraoxonase-1 and low grade inflammation
Abstract Background Functional properties of high density lipoproteins (HDL) are increasingly recognized to play a physiological role in atheroprotection. Type 2 diabetes mellitus (T2DM) is characterized by low HDL cholesterol, but the effect of chronic hyperglycemia on the anti-inflammatory capacity of HDL, a metric of HDL function, is unclear. Therefore, the aim of the present study was to establish the impact of T2DM on the HDL anti-inflammatory capacity, taking paraoxonase-1 (PON-1) activity and low grade inflammation into account. Methods The HDL anti-inflammatory capacity, determined as the ability to suppress tumor necrosis factor-α (TNF-α) induced vascular cell adhesion molecule-1 (VCAM-1) mRNA expression in endothelial cells in vitro (higher values indicate lower anti-inflammatory capacity), PON-1 (arylesterase) activity, hs-C-reactive protein (hs-CRP), serum amyloid A (SAA) and TNF-α were compared in 40 subjects with T2DM (no insulin or statin treatment) and 36 non-diabetic subjects. Results T2DM was associated with impaired HDL anti-inflammatory capacity (3.18 vs 1.05 fold increase in VCAM-1 mRNA expression; P < 0.001), coinciding with decreased HDL cholesterol (P = 0.001), apolipoprotein A-I (P = 0.038) and PON-1 activity (P = 0.023), as well as increased hs-CRP (P = 0.043) and TNF-α (P = 0.005). In all subjects combined, age- and sex-adjusted multivariable linear regression analysis demonstrated that impaired HDL anti-inflammatory capacity was associated with hyperglycemia (β = 0.499, P < 0.001), lower PON-1 activity (β = − 0.192, P = 0.030) and higher hs-CRP (β = 0.220, P = 0.016). Conclusions The HDL anti-inflammatory capacity is substantially impaired in T2DM, at least partly attributable to the degree of hyperglycemia, decreased PON-1 activity and enhanced low grade chronic inflammation. Decreased anti-inflammatory protection capacity of HDL conceivably contributes to the increased atherosclerosis risk associated with T2DM
The fractionation of adipose tissue procedure to obtain stromal vascular fractions for regenerative purposes
Autologous adipose tissue transplantation is clinically used to reduce dermal scarring and to restore volume loss. The therapeutic benefit on tissue damage more likely depends on the stromal vascular fraction of adipose tissue than on the adipocyte fraction. This stromal vascular fraction can be obtained by dissociation of adipose tissue, either enzymatically or mechanical. Enzymatic dissociation procedures are time-consuming and expensive. Therefore, we developed a new inexpensive mechanical dissociation procedure to obtain the stromal vascular fraction from adipose tissue in a time sparing way, which is directly available for therapeutic injection. This mechanical dissociation procedure is denoted as the fractionation of adipose tissue (FAT) procedure. The FAT procedure was performed in eleven patients. The composition of the FAT-stromal vascular fraction was characterized by immunohistochemistry. Adipose derived stromal cells isolated from the FAT-stromal vascular fraction were compared with adipose derived stromal cells isolated from nondissociated adipose tissue (control) for their CD-surface marker expression, differentiation and colony forming unit capacity. Case reports demonstrated the therapeutic effect of the FAT-stromal vascular fraction. The FAT-stromal vascular fraction is an enrichment of extracellular matrix containing a microvasculature and culturable adipose derived stromal cells. Adipose derived stromal cells isolated from FAT-stromal vascular fraction did not differ from adipose derived stromal cells isolated from the control group in CD-surface marker expression, differentiation and colony forming unit capacity. The FAT procedure is a rapid effective mechanical dissociation procedure to generate FAT-stromal vascular fraction ready for injection with all its therapeutic components of adipose tissue: it contains culturable adipose derived stromal cells embedded in their natural supportive extracellular matrix together with the microvasculature