441 research outputs found
Building Community Through Urban Renovation on Pittsburgh\u27s Riverfront
Every city has its most important place for citizens to promote informal sociability and urban connection with humans. The riverside is the most important urban connection in Pittsburgh. Each side of the bridge has a different development level. The design of the riverside pedestrian path can build a connection between both sides of the bridge and help urban development in the north side of Pittsburgh. The aim of the study is to analyze the connection between architectural open space, pedestrian trails, and riverway trails and to propose methods that are suitable for developing a mixed-use building that will help improve the relationship between the buildings and the urban context. The study will help develop new strategies for urban design that connects each part of the city
Scavenging of atmospheric particles by water drops
In the first paper, the mechanisms of particle capture and coalescence of aerosols by a moving water drop in the atmosphere are studied using the boundary-layer flow approximation. The particle trajectory is computed by solving the equations of motion of the particle both outside and inside the boundary layer using the Adams-Moulton method. The grazing trajectory is found by a trial-and-error technique. The collision and collection efficiencies of scavenging due to particle inertia and to the velocity gradient of the flow field are then computed for water drops ranging from 0.1 to 1.0 mm in radius and for particle of 1 - 10 µ in radius. The results obtained in this work are in good agreement with experimental data given by Walton and Woolcock.
In the second paper, the effects of intermolecular forces on the collection efficiency of submicron aerosol particles are studied. It is assumed that the intermolecular forces provide a certain region as an absorbent surface in the vicinity of the drop. Numerical results have been obtained for the cases of a water drop collecting AgCl aerosols and a water drop collecting submicron cloud droplets. It is found that the collection efficiency depends mainly on the diffusion process. Our calculations agree reasonably well with recent experimental results of Kerker for AgCl aerosols for the case of small drop --Abstract, page iii
Dynamical critical fluctuations near the QCD critical point with hydrodynamic expansion rate
In this paper, we investigate the critical slowing down effects on the
critical fluctuations driven by the expanding quark-gluon plasma with a
trajectory and expanding rate obtained from hydrodynamics. Within model A, we
numerically solved the Langevin dynamics of the non-conserved order parameter
field and find that, compared with commonly used Hubble-like expansion, the
expansion rate of a realistic hydrodynamic system is pretty large and the
associated critical slowing down effects strongly suppress the higher-order
cumulants. For an evolving system that approaches the critical point, such
critical slowing down suppression overcomes the enhancement of the critical
fluctuations, which indicates that the observed maximum fluctuations do not
necessarily associate with the evolving trajectory closest to the critical
point.Comment: 7 pages,5 figure
On the Adaptive Design Rules of Biochemical Networks in Evolution
Biochemical networks are the backbones of physiological systems of organisms. Therefore, a biochemical network should be sufficiently robust (not sensitive) to tolerate genetic mutations and environmental changes in the evolutionary process. In this study, based on the robustness and sensitivity criteria of biochemical networks, the adaptive design rules are developed for natural selection in the evolutionary process. This will provide insights into the robust adaptive mechanism of biochemical networks in the evolutionary process
Protective effect of transgenic expression of porcine heat shock protein 70 on hypothalamic ischemic and oxidative damage in a mouse model of heatstroke
<p>Abstract</p> <p>Background</p> <p>Transgenic mice have been used to examine the role of heat shock protein (HSP)72 in experimental heatstroke. Transgenic mice that were heterozygous for a porcine HSP70β gene ([+] HSP72) and transgene-negative littermate controls ([-] HSP72), under pentobarbital sodium anesthesia, were subjected to heat stress to induce heatstroke. It was found that the overexpression of HSP72 in multiple organs improved survival during heatstroke by reducing hypotension and cerebral ischemia and damage in mice. Herein we attempted to further assess the effect of heat exposure on thermoregulatory function, hypothalamic integration, and survival in unrestrained, unanesthetized [+]HSP72 and compare with those of [-]HSP72. In this research with the transgenic mice, we first conducted several biochemical, physiologic and histological determinations and then investigated the beneficial effects of HSP72 overexpression on the identified hypothalamic deficits, thermoregulatory dysfunction, and mortality during heatstroke.</p> <p>Results</p> <p>We report here that when [-]HSP72 mice underwent heat stress (ambient temperature 42.4°C for 1 h), the fraction survival and core temperature at 4 h after heat stress were found to be 0 of 12 and 34.2°C ± 0.4°C, respectively. Mice that survived to day 4 after heat stress were considered as survivors. In [+]HSP72 mice, when exposed to the same heat treatment, both fraction survival and core temperature values were significantly increased to new values of 12/12 and 37.4°C ± 0.3°C, respectively. Compared to [-]HSP mice, [+]HSP72 mice displayed lower hypothalamic values of cellular ischemia (e.g., glutamate and lactate-to-pyruvate ratio) and damage (e.g., glycerol) markers, pro-oxidant enzymes (e.g., lipid peroxidation and glutathione oxidation), pro-inflammatory cytokines (e.g., interleukin-1beta and tumor necrosis factor-alpha), and neuronal damage score evaluated 4 h after heat stress. In contrast, [+]HSP72 mice had higher hypothalamic values of antioxidant defences (e.g., glutathione peroxidase and glutathione reductase), ATP, and HSP72 expression.</p> <p>Conclusion</p> <p>This study indicates that HSP72 overexpression appears to be critical to the development of thermotolerance and protection from heat-induced hypothalamic ischemic and oxidative damage.</p
The Hippo signaling pathway coordinately regulates cell proliferation and apoptosis by inactivating Yorkie, the Drosophila Homolog of
Cytotoxic cardiac glycosides and coumarins from Antiaris toxicaria
Eight new cardiac glycosides/aglycones (antiaritoxiosides A–G, 1–7, and antiarotoxinin B, 8), two new coumarins (anticarins A–B, 41–42), and two new flavanones (antiarones L–K, 43–44) were isolated from trunk bark of Antiaris toxicaria together with 53 known compounds. The new structures were established by extensive analysis of spectroscopic data. Compound 1 (10-carboxy and 3α-hydroxy) and compounds 3–6 (10-hydroxy) contain unique substituents that are rarely found in cardiac glycosides. The cytotoxic effects of isolated compounds against ten human cancer cell lines, KB, KB-VIN, A549, MCF-7, U-87-MG, PC-3, 1A9, CAKI-1, HCT-9 and S-KMEL-2, were tested using the sulforhodamine B assay. Five compounds (12, 16, 20, 22, and 31) showed significant cytotoxicity against all ten cancer cell lines, with notable potency at the ng/mL level against some cell lines, which merits further development as clinical trial candidates
Genetic variation in the genome-wide predicted estrogen response element-related sequences is associated with breast cancer development
Comparative functional genomic analysis of Alzheimer’s affected and naturally aging brains
Background Alzheimer’s disease (AD) is a prevalent progressive neurodegenerative human disease whose cause remains unclear. Numerous initially highly hopeful anti-AD drugs based on the amyloid-β (Aβ) hypothesis of AD have failed recent late-phase tests. Natural aging (AG) is a high-risk factor for AD. Here, we aim to gain insights in AD that may lead to its novel therapeutic treatment through conducting meta-analyses of gene expression microarray data from AG and AD-affected brain. Methods Five sets of gene expression microarray data from different regions of AD (hereafter, ALZ when referring to data)-affected brain, and one set from AG, were analyzed by means of the application of the methods of differentially expressed genes and differentially co-expressed gene pairs for the identification of putatively disrupted biological pathways and associated abnormal molecular contents. Results Brain-region specificity among ALZ cases and AG-ALZ differences in gene expression and in KEGG pathway disruption were identified. Strong heterogeneity in AD signatures among the five brain regions was observed: HC/PC/SFG showed clear and pronounced AD signatures, MTG moderately so, and EC showed essentially none. There were stark differences between ALZ and AG. OXPHOS and Proteasome were the most disrupted pathways in HC/PC/SFG, while AG showed no OXPHOS disruption and relatively weak Proteasome disruption in AG. Metabolic related pathways including TCA cycle and Pyruvate metabolism were disrupted in ALZ but not in AG. Three pathogenic infection related pathways were disrupted in ALZ. Many cancer and signaling related pathways were shown to be disrupted AG but far less so in ALZ, and not at all in HC. We identified 54 “ALZ-only” differentially expressed genes, all down-regulated and which, when used to augment the gene list of the KEGG AD pathway, made it significantly more AD-specific
- …