1,536 research outputs found
Operad Structure of Poset Matrices
This paper examines operad structures derived from poset matrices by
formulating a set of new construction rules for poset matrices. In this
direction, eleven different partial composition operations will be introduced
as the basis for the construction of poset matrices of any given size by
extending the combinatorial setting of species of structures to poset matrices.
Three of these partial composition operations are shown to define an operad
structure for poset matrices. The structural properties of poset matrices and
their duals are then studied based on their associated operad constructions.Comment: arXiv admin note: substantial text overlap with arXiv:2212.1164
Effects of flow rates and composition of the filter, and decay/ingrowth correction factors involved with the determination of in situ particulate \u3csup\u3e210\u3c/sup\u3ePo and \u3csup\u3e210\u3c/sup\u3ePb in seawater
Accurate measurements of particulate 210Po (210Pop) and 210Pb (210Pbp) are required in the investigation of (i) partitioning of Po and Pb between particulate and dissolved phases and (ii) export estimates of carbon and other key trace metals from the euphotic zone via sinking particulate matter. Based on the intercomparison of different composition of the filter material (QMA, Supor, Millipore, and Pall GN6) and flow rates (2 to 8 L min), we show how these factors affect the measured concentrations of 210Pop and 210Pbp and their activity ratios (AR). As such, we recommend using Supor 0.4 μm filter and a flow rate of up to 8 L/min for the measurements of210Pop and 210Pbp. Furthermore, we inter-compared 210Pop and 210Pbp obtained by small-volume McLane and large-volume MULVFS pumps. The activities of 210Pop in MULVFS filter samples are somewhat higher than that of McLane filter samples, whereas the 210Pop/210Pb AR collected by McLane pump is distinctly lower, suggesting some fractionation in the collection process by the pumping systems. Likewise comparison of vertical profiles of 210Pop and 210Pbp obtained using McLane pumps by two independent research groups at the two intercalibration stations in the Pacific Ocean show quite similar values except in the mesopelagic waters, suggesting possible uneven loading and presence of larger gelatinous plankton in the filter. Finally, we append a detailed analysis of various correction factors for the accurate calculation of in situ 210Po and 210Pb. Presented results are relevant to the worldwide community that uses 210Po-210Pb as tracers in aquatic systems
Successful Management with Glue Injection of Arterial Rupture Seen during Embolization of an Arteriovenous Malformation Using a Flow-Directed Catheter: A Case Report
We present a case in which an arterial rupture occurring during embolization of an arteriovenous malformation of the left occipital lobe with a flow-directed microcatheter, was successfully sealed with a small amount of glue. We navigated a 1.8-Fr Magic catheter through the posterior cerebral artery, and during superselective test injection, extravasation was observed at the parieto-occipital branch. The catheter was not removed and the perforation site was successfully sealed with a small amount of glue injected through the same catheter. Prompt recognition and closure of the perforation site is essential for good prognosis
Schisandrae Fructus ethanol extract ameliorates inflammatory responses and articular cartilage damage in monosodium iodoacetate-induced osteoarthritis in rats
Schisandrae Fructus, the fruit of Schisandra chinensis (Turcz.) Baill., is widely used in traditional medicine for the treatment of a number of chronic diseases. Although, Schisandrae Fructus was recently reported to attenuate the interleukin (IL)-1β-induced inflammatory response in chondrocytes in vitro, its protective and therapeutic potential against osteoarthritis (OA) in an animal model remains unclear. Therefore, we investigated the effects of the ethanol extract of Schisandrae Fructus (SF) on inflammatory responses and cartilage degradation in a monosodium iodoacetate (MIA)-induced OA rat model. Our results demonstrated that administration with SF had a tendency to attenuate MIA-induced damage of articular cartilage as determined by a histological grade of OA. SF significantly suppressed the production of pro-inflammatory cytokines such as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α in MIA-induced OA rats. SF also effectively inhibited expression of inducible nitric oxide (NO) synthase and cyclooxygenase-2, thereby inhibiting the release of NO and prostaglandin E2. In addition, the elevated levels of matrix metalloproteinases-13 and two biomarkers for diagnosis and progression of OA, such as cartilage oligomeric matrix protein and C-telopeptide of type II collagen, were markedly ameliorated by SF administration.
These findings indicate that SF could be a potential candidate for the treatment of OA
Intercalibration studies of \u3csup\u3e210\u3c/sup\u3ePo and \u3csup\u3e210\u3c/sup\u3ePb in dissolved and particulate seawater samples
Documented is an intercalibration (IC) exercise for both 210Po and 210Pb in seawater aliquots distributed between up to eight international laboratories that followed individual protocols. Dissolved and particulate samples were provided by GEOTRACES during two IC cruises at baseline stations in the North Atlantic and North Pacific oceans. Included were surface and/or deep dissolved and particulate samples at each site, plus complete profiles analyzed by the laboratory of the lead author. An unspecified solid phase standard was also distributed with 210Po and 210Pb in secular equilibrium to confirm spike calibrations. The 210Po activities reported n = 8) for the standard were very similar with a relative standard deviation (RSD) of 3.6% and mean value indistinguishable from the certified value, confirming accurate calibration of Po spikes. For seawater samples, the agreement was strongly dependent for both nuclides on the activity of the samples. The agreement was relatively good for dissolved seawater samples (RSD = 9% to 29%, n = 4), moderate for the particulate samples (RSD = 12% to 80%, n = 8), and poor for particulate dip blanks (RSD = 50% to 200%, n = 8). Noted is the higher apparent affinity of 210Po versus 210Pb for polysulphone filter material. Some lack of reproducibility between labs may have been caused by unspecified differences in individual lab protocols and calculations. A minimum sample activity of 0.1 dpm for both nuclides is recommended for an adequate reproducible sample activity. It is suggested that a consistent set of procedures and calculations be used to optimize future 210Po and 210Pb analyses in seawater samples
Endothelin A Receptor Blockade Influences Apoptosis and Cellular Proliferation in the Developing Rat Kidney
Endothelin systems are believed to play important roles in the emergence and maintenance of functions of various organs during perinatal development, including the kidney. The present study was designed to investigate the roles of endothelin systems on physiologic renal growth and development. Newborn rat pups were treated with either Bristol-Myers Squibb-182874 (30 mg/kg/day), a selective endothelin A receptor (ETAR) antagonist, or vehicle for 7 days. To identify cellular changes, kidneys were examined for apoptotic cells by terminal deoxynucleotide transferase-mediated nick-end labeling stain and proliferating cell nuclear antigen (PCNA) by immunohistochemical (IHC) stain. To clarify the molecular control of these processes, immunoblots and reverse transcriptase-polymerase chain reaction for Clusterin, Bcl-2, Bcl-XL, Bax, and p53 were performed. ETAR antagonist treatment resulted in reduced kidney weights, decreased PCNA-positive proliferating cells, and increased apoptotic cells. The protein expressions of renal Bcl-XL and Bax in the ETAR antagonist-treated group were significantly decreased, whereas the mRNA expressions of these genes were not changed. There were no significant differences in the expressions of Clusterin, Bcl-2, and p53. In conclusion, inhibition of endogenous endothelins impairs renal growth, in which decreased cellular proliferation, increased apoptosis and decreased expressions of renal Bcl-XL and Bax are possibly implicated
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In Situ Profiling of the Three Dominant Phyla Within the Human Gut Using TaqMan PCR for Pre-Hospital Diagnosis of Gut Dysbiosis.
A microbial imbalance called dysbiosis leads to inflammatory bowel disease (IBD), which can include ulcerative colitis (UC). Fecal microbiota transplantation (FMT), a novel therapy, has recently been successful in treating gut dysbiosis in UC patients. For the FMT technique to be successful, the gut microbiota of both the healthy donors and UC patients must be characterized. For decades, next-generation sequencing (NGS) has been used to analyze gut microbiota. Despite the popularity of NGS, the cost and time constraints make it difficult to use in emergency services and activities related to the periodic monitoring of microbiota profile alterations. Hence, in this study, we developed a multiplex TaqMan qPCR assay (MTq-PCR) with novel probes to simultaneously determine the relative proportions of the three dominant microbial phyla in the human gut: Bacteroidetes, Firmicutes, and Proteobacteria. The relative proportions of the three phyla in fecal samples of either healthy volunteers or UC patients were similar when assessed NGS and the MTq-PCR. Thus, our MTq-PCR assay could be a practical microbiota profiling alternative for diagnosing and monitoring gut dysbiosis in UC patients during emergency situations, and it could have a role in screening stool from potential FMT donors
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