205 research outputs found
Crossing the Cosmological Constant Line on a Warped DGP Brane
We study dynamics of the equation of state parameter for a dark energy
component non-minimally coupled to induced gravity on a warped DGP brane. We
show that there are appropriate domains of the model parameters space that
account for crossing of the phantom divide line. This crossing, which is
possible for both branches of the scenario, depends explicitly on the values of
the non-minimal coupling and warp factor. The effect of warp factor appears in
the value of the redshift parameter at which phantom divide line crossing
occurs.Comment: 28 pages, 8 figures, 2 tables, revised version to appear in Prog.
Theor. Phy
Nuclear immobilization of DsRed1 tagged proteins: A novel tool for studying DNAâprotein interactions?
AbstractDsRed1 is a red fluorescent protein that can be used as a fusion partner with other proteins to determine their subcellular localization, similarly to the popular green fluorescent proteins (GFP). Here, we report that fusion of DsRed1 to estrogen receptor α (ERα) renders the transcription factor immobile within the nucleus. Furthermore, we show that the immobilization is dependent on DNA interaction and that the binding to the DNA can be direct as well as indirect for DsRed to immobilize with its fusion partners. This observation could provide a new tool to be used for the identification of target genes containing low affinity binding sites for several transcription factors including ERα. In addition, it could be employed for studies on proteinâDNA interactions as well as proteinâprotein interactions during protein complex formation on chromatin in the event of transcription initiation and regulation
Crossing the Phantom Divide Line in a DGP-Inspired -Gravity
We study possible crossing of the phantom divide line in a DGP-inspired
braneworld scenario where scalar field and curvature quintessence
are treated in a unified framework. With some specific form of and
by adopting a suitable ansatz, we show that there are appropriate regions of
the parameters space which account for late-time acceleration and admit
crossing of the phantom divide line.Comment: 23 Pages, 10 figs, Submitted to JCA
Population pharmacokinetics of ciprofloxacin in neonates and young infants less than 3 months age
Ciprofloxacin is used in neonates with suspected or documented Gram-negative serious infections. Currently, its use is off-label partly because of lack of pharmacokinetic studies. Within the FP7 EU project TINN (Treat Infection in NeoNates), our aim was to evaluate the population pharmacokinetics of ciprofloxacin in neonates and young infants \u3c3 months of age and define the appropriate dose in order to optimize ciprofloxacin treatment in this vulnerable population. Blood samples were collected from neonates treated with ciprofloxacin and concentrations were quantified by high-pressure liquid chromatography-mass spectrometry. Population pharmacokinetic analysis was performed using NONMEM software. The data from 60 newborn infants (postmenstrual age [PMA] range, 24.9 to 47.9 weeks) were available for population pharmacokinetic analysis. A two-compartment model with first-order elimination showed the best fit with the data. A covariate analysis identified that gestational age, postnatal age, current weight, serum creatinine concentration, and use of inotropes had a significant impact on ciprofloxacin pharmacokinetics. Monte Carlo simulation demonstrated that 90% of hypothetical newborns with a PMA of \u3c34 weeks treated with 7.5 mg/kg twice daily and 84% of newborns with a PMA â„34 weeks and young infants receiving 12.5 mg/kg twice daily would reach the AUC/MIC target of 125, using the standard EUCAST MIC susceptibility breakpoint of 0.5 mg/liter. The associated risks of overdose for the proposed dosing regimen were \u3c8%. The population pharmacokinetics of ciprofloxacin was evaluated in neonates and young infants \u3c3 months old, and a dosing regimen was established based on simulation
SSRI use and clinical outcomes in epithelial ovarian cancer
Selective serotonin reuptake inhibitor (SSRI) use is common among ovarian cancer patients. We examined the effect of SSRIs on survival and progression in ovarian cancer patients and effects of 5-HT on ovarian cancer cell (OCC) proliferation. Ovarian cancer patients from a 6-site study between 1994 and 2010 were included. Cox proportional hazards models were used for multivariate analysis. SSRI use was associated with decreased time to disease recurrence (HR 1.3, CI 1.0-1.6, p=0.03), but not overall survival (HR 1.1, CI 0.9-1.3, p=0.56). Compared to normal ovarian cells, most OCCs had elevated 5-HT2A receptor mRNA expression (up to 1600 fold greater expression). Clonogenic survival increased in cells treated with 10 uM (1.6 fold, p<0.001) and 20uM (1.9 fold, p=0.018) 5-HT. Mice receiving 5-HT injections had increases in tumor weight (p=0.07) and nodules (p=0.08) with increased Ki67 expression. Injections with sertraline doubled mean tumor weight in mice (p=0.16). 5-HT and sertraline both increased Ki67 expression in mouse tumors (p < 0.001). Patients using SSRIs had significantly decreased time to disease progression. It is possible that SSRIs alter serotonin levels in the tumor microenvironment, resulting in activation of proliferation pathways. Further characterization of serotonergic pathways in ovarian cancer is recommended to demonstrate safety of these medications
Management of Urban Waters with Nature-Based Solutions in Circular CitiesâExemplified through Seven Urban Circularity Challenges
Nature-Based Solutions (NBS) have been proven to effectively mitigate and solve resource depletion and climate-related challenges in urban areas. The COST (Cooperation in Science and Technology) Action CA17133 entitled âImplementing nature-based solutions (NBS) for building a resourceful circular cityâ has established seven urban circularity challenges (UCC) that can be addressed effectively with NBS. This paper presents the outcomes of five elucidation workshops with more than 20 European experts from different backgrounds. These international workshops were used to examine the effectiveness of NBS to address UCC and foster NBS implementation towards circular urban water management. A major outcome was the identification of the two most relevant challenges for water resources in urban areas: âRestoring and maintaining the water cycleâ (UCC1) and âWater and waste treatment, recovery, and reuseâ (UCC2). s Moreover, significant synergies with âNutrient recovery and reuseâ, âMaterial recovery and reuseâ, âFood and biomass productionâ, âEnergy efficiency and recoveryâ, and âBuilding system recoveryâ were identified. Additionally, the paper presents real-life case studies to demonstrate how different NBS and supporting units can contribute to the UCC. Finally, a case-based semi-quantitative assessment of the presented NBS was performed. Most notably, this paper identifies the most typically employed NBS that enable processes for UCC1 and UCC2. While current consensus is well established by experts in individual NBS, we presently highlight the potential to address UCC by combining different NBS and synergize enabling processes. This study presents a new paradigm and aims to enhance awareness on the ability of NBS to solve multiple urban circularity issues.publishedVersio
Effect of tissue-harvesting site on yield of stem cells derived from adipose tissue: implications for cell-based therapies
The stromal vascular fraction (SVF) of adipose tissue contains an abundant population of multipotent adipose-tissue-derived stem cells (ASCs) that possess the capacity to differentiate into cells of the mesodermal lineage in vitro. For cell-based therapies, an advantageous approach would be to harvest these SVF cells and give them back to the patient within a single surgical procedure, thereby avoiding lengthy and costly in vitro culturing steps. However, this requires SVF-isolates to contain sufficient ASCs capable of differentiating into the desired cell lineage. We have investigated whether the yield and function of ASCs are affected by the anatomical sites most frequently used for harvesting adipose tissue: the abdomen and hip/thigh region. The frequency of ASCs in the SVF of adipose tissue from the abdomen and hip/thigh region was determined in limiting dilution and colony-forming unit (CFU) assays. The capacity of these ASCs to differentiate into the chondrogenic and osteogenic pathways was investigated by quantitative real-time polymerase chain reaction and (immuno)histochemistry. A significant difference (Pâ=â0.0009) was seen in ASC frequency but not in the absolute number of nucleated cells between adipose tissue harvested from the abdomen (5.1â±â1.1%, meanâ±âSEM) and hip/thigh region (1.2â±â0.7%). However, within the CFUs derived from both tissues, the frequency of CFUs having osteogenic differentiation potential was the same. When cultured, homogeneous cell populations were obtained with similar growth kinetics and phenotype. No differences were detected in differentiation capacity between ASCs from both tissue-harvesting sites. We conclude that the yield of ASCs, but not the total amount of nucleated cells per volume or the ASC proliferation and differentiation capacities, are dependent on the tissue-harvesting site. The abdomen seems to be preferable to the hip/thigh region for harvesting adipose tissue, in particular when considering SVF cells for stem-cell-based therapies in one-step surgical procedures for skeletal tissue engineering
Eco-efficiency measurement and material balance principle:an application in power plants Malmquist Luenberger Index
Incorporating Material Balance Principle (MBP) in industrial and agricultural performance measurement systems with pollutant factors has been on the rise in recent years. Many conventional methods of performance measurement have proven incompatible with the material flow conditions. This study will address the issue of eco-efficiency measurement adjusted for pollution, taking into account materials flow conditions and the MBP requirements, in order to provide ârealâ measures of performance that can serve as guides when making policies. We develop a new approach by integrating slacks-based measure to enhance the Malmquist Luenberger Index by a material balance condition that reflects the conservation of matter. This model is compared with a similar model, which incorporates MBP using the trade-off approach to measure productivity and eco-efficiency trends of power plants. Results reveal similar findings for both models substantiating robustness and applicability of the proposed model in this paper
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