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Various types of arterial anastomosis are used in the recipient beds of clinical free flap transfers, but their respective hemodynamic efficiencies have not yet been elucidated. The purpose of this study was to investigate the relationship between the type of arterial anastomosis and the area of free flap survival. The authors transferred free three-territory flaps in rats using three different types of arterial anastomosis (end-to-end, end-to-side, and retrograde) and compared their areas of survival. Sixty Wistar rats were divided into three groups (n = 20 in each group). A free three-territory flap was elevated and transferred microsurgically to the left ventral region in each rat. The arterial anastomosis was performed in an antegrade end-to-end fashion in group 1, in an end-to-side fashion in group 2, and in a retrograde end-to-end fashion in group 3. The arterial blood flow to the flap was measured 30 minutes after revascularization. On day 5, the area of flap survival was eva...

Experimental investigations are performed to measure the detailed heat transfer coefficient and static pressure distributions on the squealer tip of a gas turbine blade in a five-bladed stationary linear cascade. The blade is a two-dimensional model of a modern first-stage gas turbine rotor blade with a blade tip profile of a GE-E3 aircraft gas turbine engine rotor blade. A squealer (recessed) tip with a 3.77 percent recess is considered here. The data on the squealer tip are also compared with a flat tip case. All measurements are made at three different tip gap clearances of about 1, 1.5, and 2.5 percent of the blade span. Two different turbulence intensities of 6.1 and 9.7 percent at the cascade inlet are also considered for heat transfer measurements. Static pressure measurements are made in the midspan and near-tip regions, as well as on the shroud surface opposite to the blade tip surface. The flow condition in the test cascade corresponds to an overall pressure ratio of 1.32 ...

The objective of this work is to develop and validate a coupled boundary element method-finite element method to simulate the transient fluid-structure interaction response of tidal turbines subject to spatially varying inflow. The focus is on tidal turbines, although the methodology is also applicable for the analysis and design of wind turbines. An overview of the formulation for both the fluid and solid domains, and the fluid-structure interaction algorithms, is presented. The model is validated by comparing the predicted thrust and power measurements, as well as cavitation patterns, with experimental measurements and observations for an 800 mm marine current turbine presented in the work of Bahaj et al. (2007, “Power and Thrust Measurements of Marine Current Turbines Under Various Hydrodynamic Flow Conditions in a Cavitation Tunnel and a Towing Tank,” Renewable Energy, 32, pp. 407–426). Additional numerical results are shown for the same turbine, but scaled up to 20 m in diameter, operating in a tidal boundary layer flow with a water depth of 30 m. The results show that transient cavitation will develop near the blade tip when the blades are near the free surface at highly-loaded off-design conditions, and the blades will undergo excessive deformation because of the high fluid loading and slender blade profile. The results also show that the natural frequencies of the blades are significantly reduced when operating in water, as compared with when operating in air, because of added-mass effects. In addition to demonstrating the need for proper consideration for fluid cavitation and structural response, current design challenges for both wind and tidal turbines are discussed.

The hexaethylene glycol monododecyl ether (C(12)E(6)) micelles at concentrations up to 10% have been studied in their isotropic phase (10-48 degrees C) by means of small angle neutron scattering (SANS) and photon correlation spectroscopy (PCS). The SANS data obtained at low temperatures could be unequivocally interpreted as a result of scattering from a suspension of compact globular micelles with the shape of a triaxial ellipsoid or a short end-capped elliptical rod. Different models have been applied to analyze the SANS data obtained at higher temperatures: (i) elongated rod-like micelles with purely sterical interactions, (ii) compact globular micelles with a weak attractive potential, and (iii) globular micelles influenced by the critical phenomena in the whole temperature range studied. The good quality of the experimental data indicated model (i) as the best fit for our data. The diffusion coefficients obtained from the PCS measurements have been compared to the diffusion coefficients calculated for the rod-like micelles--results of the SANS data analysis. A good agreement was achieved using the solvent viscosity, in agreement with the theoretical predictions for sterically interacting globular colloidal particles. Finally, the SANS results obtained at 24 degrees C were compared to the micelle self-diffusion coefficients previously measured by means of fluorescence correlation spectroscopy (FCS) at this temperature. The good agreement obtained after scaling the data with solution viscosity supports the validity of the generalized Stokes-Einstein relation in sterically interacting systems: the product of the colloidal particle self-diffusion coefficient and the macroscopic viscosity remains constant in a broad range of concentrations. It has been concluded that the FCS technique in combination with simple viscosity measurements might serve as a tool for estimating the micellar size and shape.

It is sometimes argued that the fact that possession of perfect knowledge about the future is impossible, means that it is impossible for decisions to be rational. This reasoning is fallacious. If rationality is given a new interpretation, then decisions can be considered rational. A theory of decision that has as its basis Peirce's theory of abduction can provide a new way of understanding decisions as rational processes. The Peircean theory of decision (i) considers decisions as part of a complete strategy, and (ii) shows that decision making ...

... It is Harley, the “limp-dicked first white man born” (p. 31) narrator, who encounters and gathers heteroglot languages to write a “simple family history” that contests the larger history of white Australia. ... Harley floats away unless anchored to weighty objects. ...

SIRT6 belongs to the sirtuin family of protein lysine deacetylases, which regulate aging and genome stability. We found that human SIRT6 has a role in promoting DNA end resection, a crucial step in DNA double-strand break (DSB) repair by homologous recombination. SIRT6 depletion impaired the accumulation of replication protein A and single-stranded DNA at DNA damage sites, reduced rates of homologous recombination, and sensitized cells to DSB-inducing agents. We identified the DSB resection protein CtIP [C-terminal binding protein (CtBP) interacting protein] as a SIRT6 interaction partner and showed that SIRT6-dependent CtIP deacetylation promotes resection. A nonacetylatable CtIP mutant alleviated the effect of SIRT6 depletion on resection, thus identifying CtIP as a key substrate by which SIRT6 facilitates DSB processing and homologous recombination. These findings further clarify how SIRT6 promotes genome stability.