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Background: Counseling and anticipatory guidance of the expected course of treatment for women newly diagnosed with metastatic breast cancer (MBC) are difficult due to multiple factors influencing survival following MBC therapy. In order to better tailor counseling at the onset and through the duration of MBC we used non-clinical trial data to better characterize real life experience of sequential MBC treatment.We examined the following aims: (1) What demographic and tumor characteristics are predictive of survival in MBC? (2)What is the median duration of each sequential chemotherapy regimen and subsequent survival of women following each sequence of chemotherapy regimen in MBC? Methods: Retrospective study included 792women diagnosed from January 1999 through December 2009 at the University of Pittsburgh Cancer Institute Breast Cancer Program. Results: Median duration of sequential chemotherapy regimen and median survival from completion of sequence of chemotherapy regimens were relatively short with a wide range of treatment duration and survival. Characteristics for poor survival included hormone status, human epidermal growth factor receptor-2 (HER 2/neu) status, and increased number and type of metastatic sites.Women who took more than the second sequential chemotherapy regimens had no more than median 3 months of treatment duration and 6 months survival from treatment termination. Discussion: Median clinical response and survival shorten with sequential chemotherapy regimen but with wide ranges. The rare clinical response of the minority should not set the standard for treatment expectations. All cancer clinicians, including oncology nurses, must ensure that patients are receiving tailored counseling regarding their specific risks and benefits for sequential MBC chemotherapy.

Background: Counseling and anticipatory guidance of the expected course of treatment for women newly diagnosed with metastatic breast cancer (MBC) are difficult due to multiple factors influencing survival following MBC therapy. In order to better tailor counseling at the onset and through the duration of MBC we used non-clinical trial data to better characterize real life experience of sequential MBC treatment.We examined the following aims: (1) What demographic and tumor characteristics are predictive of survival in MBC? (2)What is the median duration of each sequential chemotherapy regimen and subsequent survival of women following each sequence of chemotherapy regimen in MBC? Methods: Retrospective study included 792women diagnosed from January 1999 through December 2009 at the University of Pittsburgh Cancer Institute Breast Cancer Program. Results: Median duration of sequential chemotherapy regimen and median survival from completion of sequence of chemotherapy regimens were relatively short with a wide range of treatment duration and survival. Characteristics for poor survival included hormone status, human epidermal growth factor receptor-2 (HER 2/neu) status, and increased number and type of metastatic sites.Women who took more than the second sequential chemotherapy regimens had no more than median 3 months of treatment duration and 6 months survival from treatment termination. Discussion: Median clinical response and survival shorten with sequential chemotherapy regimen but with wide ranges. The rare clinical response of the minority should not set the standard for treatment expectations. All cancer clinicians, including oncology nurses, must ensure that patients are receiving tailored counseling regarding their specific risks and benefits for sequential MBC chemotherapy.

The effects on vegetation of three small mammalian herbivores were determined experimentally in a subalpine meadow in southwestern Colorado. Pikas (Ochotona princeps) inhabit talus and forage on surrounding vegetation. Their foraging was consistent with predictions of central place foraging theory. Amount of foraging decreased with distance from talus, whereas selectivity increased. These patterns are expected to influence the resources used by pikas, and plant abundance and species richness increased with distance from talus, as predicted. Experimental exclusion of pikas demonstrated that a significant portion of the lower vegetational cover and species richness was due to pikas. A model postulating that the effects of pikas on vegetation resulted from a gradient in herbivory, and a corresponding gradient in the relative importance of herbivory and competition among plants, was generally supported. Total vegetational abundance and species richness increased in the absence of pikas. The increase in pika exclosures compared to controls was greatest near talus and decreased with distance. The initial effect of pika exclusion on cushion plants (assumed to be the poorest competitors among the plants in the absence of herbivory) was positive near talus, but was insignificant and tended to be negative at greater distance from talus. The prediction of eventual decline of cushion plant populations in the absence of pikas was supported in two of three sites after three years. The effects on vegetation of two co-occurring herbivores, pocket gophers (Thomomys talpoides) and voles (Microtus montanus), were evaluated using a factorial exclusion experiment. Non-independence of effects was assessed as presence of a significant interaction term in 2-way ANOVA. Gopher x vole interaction terms were at least marginally significant for many analyses. Results only weakly suggested direct foraging interactions between gophers and voles, but showed considerable importance of indirect, pla

In this study I present a new mechanism for the evolution of male display as a consequence of female choice. I use a population genetic model to show that if female preferences for better males are based on a cue that is an integral part of male adaptation, a display may evolve if it amplifies the variance in this cue, and hence increases female resolution power with respect to male quality. This evolutionary mechanism is used as a core of a theory that explains the evolution of male display and adaptive female choice (i.e. female preferences that evolve because of their association with high quality genes). I argue that because an amplifying display (termed "amplifier") decreases mating success of males of poor quality, modifiers are likely to evolve that decrease the expression of the amplifier when associated with the poor quality males. As a result, the amplifier's expression becomes an indicator of male quality, and provides sufficient conditions for the evolution of a new type of female choice that is based on the amplifier's expression. This process may lead, in turn, to further changes in both female choice and male display, emphasizing either the amplifying effect of displays or their indicating effect. I show that the direction of these changes may depend on the cost that the amplifier confers on male viability, and on the degree of polygyny of the mating system in concern. I also outline explicit predictions for empirical tests.

The laminar, two-dimensional flow of a viscous vortex, driven by tangential fluid injection in a porous cylindrical container, is considered. The jets are idealized as sources of mass and momentum. The tangential velocity profile in the annular region between the jet input radius of the cylinder is found analytically as a solution of the tangential momentum equation. The peripheral wall shear is evaluated with and without radial fluid injection through the cylinder wall. For a given tangential velocity in the vortex, radial fluid injection through the porous wall substantially reduces the shear. The effect of radial fluid injection on the fraction of the jet velocity that is recovered in the vortex is found by means of a torque balance, including the torque required to accelerate the radially injected fluid to the peripheral vortex velocity. For a given total mass flow through the center of the vortex, radial fluid injection is always detrimental to the velocity recovery in the vortex; that is, for a given jet velocity, diversion of a fraction of the mass flow from tangential to radial injection always results in a reduced vortex strength. The results for zero radial fluid injection are compared with experimental data for which the flow was turbulent. The theory predicts the recovery accurately even for turbulent flow, provided an appropriate turbulent eddy viscosity is included in the evaluation of the Reynolds number.

A simplified method is presented for the estimation of heat transfer and pressure loss in problems involving the flow of a compressible fluid through a constant area pipe in the presence of friction and heat addition. No analysis is given; only significant formulas are presented. An example concerning the heat transfer and pressure drop through a nuclear rocket reactor is used to illustrate the practical design application of the formulas. The calculation leads to design curves indicating the effects of varying inlet Mach number on pressure loss, exit Mach number and total area required to pass a given mass flow. (Author)

Binary diffusion in confined vortices (of the type considered for hydrodynamic containment in a gas-core nuclear rocket) is investigated theoretically and experimentally. An approximate integral solution is presented for the species distribution resulting from the actions of convection, and concentration and pressure diffusion. The flow model includes secondary flows induced by boundary-layer interaction on the end walls of the vortex chamber. The qualitative effect of varying the degree of boundary-layer interaction is demonstrated by a flow-visualization experiment using dye in a water vortex. Quantitative data are obtained from an experiment in which iodine vapor and heated helium are premixed and injected tangentially into a vortex chamber, forming a lowdensity, high-velocity flow field. The resulting radial distribution of iodine concentration is determined optically. Peak density ratios of iodine to helium within the vortex are found to be as much as three times the density ratio of the mixture flowing into the chamber. The experimental data agree favorably with the theoretical predictions and demonstrate that a gas of high molecular weight can be substantially retained in a vortex comprised of a gas of low molecular weight. (Author)