bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficacy of Sunitinib and Sorafenib in Metastatic Papillary and Chromophobe Renal Cell Carcinoma
Authors: Choueiri Toni K. , Plantade Anne , Elson Paul , Negrier Sylvie , Ravaud Alain , Oudard Stephane , Zhou Ming , Rini Brian I. , Bukowski Ronald M. , Escudier Bernard 
Published: December 2007

Purpose Sunitinib and sorafenib are novel tyrosine kinase inhibitors (TKIs) that have shown significant clinical activity in metastatic clear cell renal cell carcinoma (RCC). The activity of sunitinib and sorafenib in non–clear cell histologies has not been evaluated. Patients and Methods Clinical features at study entry and treatment outcomes were evaluated in patients with metastatic papillary RCC (PRCC) and chromophobe RCC (ChRCC) who received either sunitinib or sorafenib as their initial TKI treatment in five US and French institutions. Response rate and survival were documented. Fisher's exact test was used for categoric variables, and the Kaplan-Meier method was used to estimate survival. Results Fifty-three patients were included. The number of patients with papillary and chromophobe histologies was 41 (77%) and 12 (23%), respectively. Response rate, progression-free survival (PFS) time, and overall survival time for the entire cohort were 10%, 8.6 months, and 19.6 months, respectively. Three (25%) of 12 ChRCC patients achieved a response (two patients treated with sorafenib and one treated with sunitinib), and PFS was 10.6 months. Two (4.8%) of 41 PRCC patients achieved a response (both patients were treated with sunitinib). PFS for the whole cohort was 7.6 months. Sunitinib-treated PRCC patients had a PFS of 11.9 months compared with 5.1 months for sorafenib-treated patients (P < .001). Conclusion Patients with PRCC and ChRCC may have prolonged PFS from sunitinib and sorafenib, although clinical responses remain overall low in PRCC. Additional prospective trials with these agents in non–clear cell RCC will further clarify their use in the future.
Flow patterns of larval fish: undulatory swimming in the intermediate flow regime
Authors: Müller Ulrike K. , van den Boogaart Jos G. M. , van Leeuwen Johan L. 
Published: December 2007

SUMMARYFish larvae, like many adult fish, swim by undulating their body. However,their body size and swimming speeds put them in the intermediate flow regime,where viscous and inertial forces both play an important role in the interaction between fish and water. To study the influence of the relatively high viscous forces compared with adult fish, we mapped the flow around swimming zebrafish (Danio rerio) larvae using two-dimensional digital particle image velocimetry (2D-DPIV) in the horizontal and transverse plane of the fish. Fish larvae initiate a swimming bout by bending their body into a C shape. During this initial tail-beat cycle, larvae shed two vortex pairs in the horizontal plane of their wake, one during the preparatory and one during the subsequent propulsive stroke. When they swim `cyclically' (mean swimming speed does not change significantly between tail beats), fish larvae generate a wide drag wake along their head and anterior body. The flow along the posterior body is dominated by the undulating body movements that cause jet flows into the concave bends of the body wave. Patches of elevated vorticity form around the jets, and travel posteriorly along with the body wave, until they are ultimately shed at the tail near the moment of stroke reversal. Behind the larva, two vortex pairs are formed per tail-beat cycle (the tail beating once left-to-right and then right-to-left) in the horizontal plane of the larval wake. By combining transverse and horizontal cross sections of the wake, we inferred that the wake behind a cyclically swimming zebrafish larva contains two diverging rows of vortex rings to the left and right of the mean path of motion, resembling the wake of steadily swimming adult eels. When the fish larva slows down at the end of a swimming bout, it gradually reduces its tail-beat frequency and amplitude, while the separated boundary layer and drag wake of the anterior body extend posteriorly to envelope the entire larva. This drag wake is considerably wider than the larval body. The effects of the intermediate flow regime manifest as a thick boundary layer and in the quick dying-off of the larval wake within less than half a second.
Vortex-wake interactions of a flapping foil that models animal swimming and flight
Authors: Lentink David , Muijres Florian T. , Donker-Duyvis Frits J. , van Leeuwen Johan L. 
Published: December 2007

SUMMARYThe fluid dynamics of many swimming and flying animals involves the generation and shedding of vortices into the wake. Here we studied the dynamics of similar vortices shed by a simple two-dimensional flapping foil in a soap-film tunnel. The flapping foil models an animal wing, fin or tail in forward locomotion. The vortical flow induced by the foil is correlated to(the resulting) thickness variations in the soap film. We visualized these thickness variations through light diffraction and recorded it with a digital high speed camera. This set-up enabled us to study the influence of foil kinematics on vortex-wake interactions. We varied the dimensionless wavelength of the foil (λ*=4–24) at a constant dimensionless flapping amplitude (A*=1.5) and geometric angle of attack amplitude (Aα,geo=15°). The corresponding Reynolds number was of the order of 1000. Such values are relevant for animal swimming and flight.We found that a significant leading edge vortex (LEV) was generated by the foil at low dimensionless wavelengths (λ*&lt;10). The LEV separated from the foil for all dimensionless wavelengths. The relative time(compared with the flapping period) that the unstable LEV stayed above the flapping foil increased for decreasing dimensionless wavelengths. As the dimensionless wavelength decreased, the wake dynamics evolved from a wavy von Kármán-like vortex wake shed along the sinusoidal path of the foil into a wake densely packed with large interacting vortices. We found that strongly interacting vortices could change the wake topology abruptly. This occured when vortices were close enough to merge or tear each other apart. Our experiments show that relatively small changes in the kinematics of a flapping foil can alter the topology of the vortex wake drastically.
Contractile properties of the pigeon supracoracoideus during different modes of flight
Authors: Tobalske Bret W. , Biewener Andrew A. 
Published: December 2007

SUMMARYThe supracoracoideus (SUPRA) is the primary upstroke muscle for avian flight and is the antagonist to the downstroke muscle, the pectoralis (PECT). We studied in vivo contractile properties and mechanical power output of both muscles during take-off, level and landing flight. We measured muscle length change and activation using sonomicrometry and electromyography, and muscle force development using strain recordings on the humerus. Our results support a hypothesis that the primary role of the SUPRA is to supinate the humerus. Antagonistic forces exerted by the SUPRA and PECT overlap during portions of the wingbeat cycle, thereby offering a potential mechanism for enhancing control of the wing. Among flight modes, muscle strain was approximately the same in the SUPRA (33–40%) and the PECT(35–42%), whereas peak muscle stress was higher in the SUPRA(85–126 N m–2) than in the PECT (50–58 N m–2). The SUPRA mainly shortened relative to resting length and the PECT mainly lengthened. We estimated that elastic energy storage in the tendon of the SUPRA contributed between 28 and 60% of the net work of the SUPRA and 6–10% of the total net mechanical work of both muscles. Mechanical power output in the SUPRA was congruent with the estimated inertial power required for upstroke, but power output from the PECT was only 42–46% of the estimated aerodynamic power requirements for flight. There was a significant effect of flight mode upon aspects of the contractile behavior of both muscles including strain, strain rate, peak stress, work and power.
When wings touch wakes: understanding locomotor force control by wake–wing interference in insect wings
Authors: Lehmann Fritz-Olaf 
Published: December 2007

SUMMARYUnderstanding the fluid dynamics of force control in flying insects requires the exploration of how oscillating wings interact with the surrounding fluid. The production of vorticity and the shedding of vortical structures within the stroke cycle thus depend on two factors: the temporal structure of the flow induced by the wing's own instantaneous motion and the flow components resulting from both the force production in previous wing strokes and the motion of other wings flapping in close proximity. These wake–wing interactions may change on a stroke-by-stroke basis,confronting the neuro-muscular system of the animal with a complex problem for force control. In a single oscillating wing, the flow induced by the preceding half stroke may lower the wing's effective angle of attack but permits the recycling of kinetic energy from the wake via the wake capture mechanism. In two-winged insects, the acceleration fields produced by each wing may strongly interact via the clap-and-fling mechanism during the dorsal stroke reversal. Four-winged insects must cope with the fact that the flow over their hindwings is affected by the presence of the forewings. In these animals, a phase-shift between the stroke cycles of fore- and hindwing modulates aerodynamic performance of the hindwing via leading edge vortex destruction and changes in local flow condition including wake capture. Moreover, robotic wings demonstrate that phase-lag during peak performance and the strength of force modulation depend on the vertical spacing between the two stroke planes and the size ratio between fore- and hindwing. This study broadly summarizes the most prominent mechanisms of wake–wing and wing–wing interactions found in flapping insect wings and evaluates the consequences of these processes for the control of locomotor forces in the behaving animal.
An overview of a Lagrangian method for analysis of animal wake dynamics
Authors: Peng Jifeng , Dabiri John O. 
Published: December 2007

SUMMARY
The fluid dynamic analysis of animal wakes is becoming increasingly popular in studies of animal swimming and flying, due in part to the development of quantitative flow visualization techniques such as digital particle imaging velocimetry (DPIV). In most studies, quasi-steady flow is assumed and the flow analysis is based on velocity and/or vorticity fields measured at a single time instant during the stroke cycle. The assumption of quasi-steady flow leads to neglect of unsteady (time-dependent) wake vortex added-mass effects,which can contribute significantly to the instantaneous locomotive forces. In this paper we review a Lagrangian approach recently introduced to determine unsteady wake vortex structure by tracking the trajectories of individual fluid particles in the flow, rather than by analyzing the velocity/vorticity fields at fixed locations and single instants in time as in the Eulerian perspective. Once the momentum of the wake vortex and its added mass are determined, the corresponding unsteady locomotive forces can be quantified. Unlike previous studies that estimated the time-averaged forces over the stroke cycle, this approach enables study of how instantaneous locomotive forces evolve over time. The utility of this method for analyses of DPIV velocity measurements is explored, with the goal of demonstrating its applicability to data that are typically available to investigators studying animal swimming and flying. The methods are equally applicable to computational fluid dynamics studies where velocity field calculations are available.
Muscle specialization in the squid motor system
Authors: Kier William M. , Schachat Frederick H. 
Published: December 2007

SUMMARYAlthough muscle specialization has been studied extensively in vertebrates,less is known about the mechanisms that have evolved in invertebrate muscle that modulate muscle performance. Recent research on the musculature of squid suggests that the mechanisms of muscle specialization in cephalopods may differ from those documented in vertebrates. Muscle diversity in the development and the evolution of cephalopods appears to be characterized by modulation of the dimensions of the myofilaments, in contrast to the relatively fixed myofilament dimensions of vertebrate muscle. In addition, the arrangement of the myofilaments may also be altered, as has been observed in the extensor muscle fibres of the prey capture tentacles of squid and cuttlefish, which show cross-striation and thus differ from the obliquely striated pattern of most cephalopod locomotor muscle fibres. Although biochemical specializations that reflect differences in aerobic capacity have been documented previously for specific layers of the mantle muscle of squid,comparison of protein profiles of myofilament preparations from the fast cross-striated tentacle fibres and slow obliquely striated fibres from the arms has revealed remarkably few differences in myofilament lattice proteins. In particular, previous studies using a variety of SDS-PAGE techniques and peptide mapping of the myosin heavy chain were unable to resolve differences in the myosin light and heavy chains. Since these techniques cannot exclude the presence of a highly conserved variant that differs in only a few amino acids, in this study semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) analysis of myosin heavy chain messenger RNAs (mRNAs) from the cross-striated tentacle and obliquely striated arm muscle fibres was conducted. This analysis showed that a previously reported alternatively spliced isoform of the squid myosin motor domain is present only in low abundance in both muscle types and therefore differential expression of the two myosins cannot explain the difference in contractile properties. It thus appears that modulation of the contractile properties of the musculature of squid and other cephalopods occurs primarily through variation in the arrangement and dimensions of the myofilaments.
Near- and far-field aerodynamics in insect hovering flight: an integrated computational study
Authors: Aono Hikaru , Liang Fuyou , Liu Hao 
Published: December 2007

SUMMARYWe present the first integrative computational fluid dynamics (CFD) study of near- and far-field aerodynamics in insect hovering flight using a biology-inspired, dynamic flight simulator. This simulator, which has been built to encompass multiple mechanisms and principles related to insect flight, is capable of `flying' an insect on the basis of realistic wing–body morphologies and kinematics. Our CFD study integrates near-and far-field wake dynamics and shows the detailed three-dimensional (3D)near- and far-field vortex flows: a horseshoe-shaped vortex is generated and wraps around the wing in the early down- and upstroke; subsequently, the horseshoe-shaped vortex grows into a doughnut-shaped vortex ring, with an intense jet-stream present in its core, forming the downwash; and eventually,the doughnut-shaped vortex rings of the wing pair break up into two circular vortex rings in the wake. The computed aerodynamic forces show reasonable agreement with experimental results in terms of both the mean force (vertical,horizontal and sideslip forces) and the time course over one stroke cycle(lift and drag forces). A large amount of lift force (approximately 62% of total lift force generated over a full wingbeat cycle) is generated during the upstroke, most likely due to the presence of intensive and stable,leading-edge vortices (LEVs) and wing tip vortices (TVs); and correspondingly,a much stronger downwash is observed compared to the downstroke. We also estimated hovering energetics based on the computed aerodynamic and inertial torques, and powers.
Biorobotic insights into how animals swim
Authors: Bandyopadhyay Promode R. , Beal David N. , Menozzi Alberico 
Published: December 2007

SUMMARY
Many animals maneuver superbly underwater using their pectoral appendages. These animals range from sunfish, which have flexible, low aspect ratio fins,to penguins, which have relatively stiff, high aspect ratio wings. Biorobotics is a means of gaining insight into the mechanisms these animals use for maneuvering. In this study, experiments were carried out with models of abstracted penguin wings, and hydrodynamic characteristics – in particular, efficiency – were measured directly. A cross-flow vortex model of the unsteady force mechanism was developed that can compute instantaneous lift and drag forces accurately. This makes use of the steady characteristics of the fin and proposes that cross-flow drag vortices of bluff bodies in steady flow are analogous to dynamic stall vortices and that fin oscillation is a means for keeping the vortices attached to the fin. From what has been reported for sunfish with pectoral fins to our current measurements for single abstracted penguin wings, we infer that the maximum hydrodynamic efficiency has remained largely unchanged. A selection algorithm was used to rapidly find the fin oscillation parameters for optimum efficiency. Finally,we compared the measurements on the penguin-like relatively stiff fins and the reported flow visualization of flexible sunfish pectoral fins. The flexible pectoral fins of station-keeping sunfish exhibit a rich repertoire of capability such as the formation of dynamic stall vortices simultaneously on two leading edges during part of the cycle, changes in projected area in different planes, and the vectoring of jets. However, such fins may not be scalable to larger biorobotic vehicles and relatively stiff fins appear to be better suited instead, albeit with somewhat limited station-keeping ability.
A spatially explicit model of muscle contraction explains a relationship between activation phase, power and ATP utilization in insect flight
Authors: Tanner Bertrand C. W. , Regnier Michael , Daniel Thomas L. 
Published: December 2007

SUMMARY
Using spatially explicit, stochastically kinetic, molecular models of muscle force generation, we examined the relationship between mechanical power output and energy utilization under differing patterns of length change and activation. A simulated work loop method was used to understand prior observations of sub-maximal power output in the dominant flight musculature of the hawkmoth Manduca sexta L. Here we show that mechanical work output and energy consumption (via ATP) vary with the phase of activation, although they do so with different phase sensitivities. The phase relationship for contraction efficiency (the ratio of power output to power input) differs from the phase relationships of energy consumption and power output. To our knowledge, this is the first report to suggest that ATP utilization by myosin cross-bridges varies strongly with the phase of activation in muscle undergoing cyclic length changes.
Over-Cladding of Aluminum Framed Curtainwalls and Skylights
Authors: Boyd Jon M. 
Published: December 2007

Abstract
The need to upgrade the performance of existing building façade systems provides many opportunities for innovation and the creative reuse of existing building components. As many mid-20th century building enclosure systems age, they exhibit performance deficiencies, both in the form of deteriorating performance and in lagging performance as weighed against newer technologies. The installation of replacement exterior envelope systems on existing facilities provides many challenges, especially in fully occupied buildings. Over-cladding of existing metal and glass curtainwall and skylight systems, wherein portions of the pre-existing systems are integrated into the new construction, provides significant opportunities to resolve construction phase issues while providing improved functionality to the completed building envelope.
This paper will address two case studies in which contemporary aluminum and glass elements were combined with pre-existing mid-1900s aluminum framed cladding elements to provide two wholly new enclosure systems with significantly improved performance characteristics. The case studies deal with two very different sets of project objectives, site constraints and project solutions, but share common approaches and eventual solutions. The paper presents the problems posed by the pre-existing systems, the site investigations conducted to confirm existing conditions and site restrictions, reasons for considering the specific replacement cladding approaches, specific project constraints, the approaches used in development of the new over-clad solutions, and considerations in the design, development, and construction phase delivery of these projects. Applicability of these approaches to other types of contemporary building enclosure types is explored as well.
Proposed Method for Determining the Residual Mortar Content of Recycled Concrete Aggregates
Authors: Abbas Abdelgadir , Fathifazl Gholamreza , Burkan Isgor O. , Razaqpur A. G. , Fournier Benoit , Foo Simon 
Published: December 2007

Abstract
Recycling concrete from demolition of existing structures and using it as recycled concrete aggregates (RCAs) in structural-grade concrete have significant economic and environmental benefits. Currently, only a small portion of the concrete waste is reused in building construction, while most of it is used as either pavement base course or sent to landfills for disposal. The lack of confidence in the material properties of the concrete produced with RCAs is generally the main reason for its under-utilization in structural concrete. It has been demonstrated in the literature that the amount of residual mortar attached to the original (or “virgin”) aggregate particles is one of the factors affecting the material properties of RCAs. Therefore, before using RCAs in new concrete, it is crucial that the residual mortar content (RMC) is determined accurately; however, currently there is no standard procedure to determine this quantity. In this paper, an experimental method is proposed to determine the RMC of RCAs. The method comprises a combination of mechanical and chemical stresses that disintegrate the residual mortar and destroy the bond between the mortar and the natural aggregates. The mechanical stresses are created through subjecting RCA to freeze-and-thaw action, while the chemical degradation is achieved through exposure of the RCA to a sodium sulphate solution. The results of the proposed test procedure are validated by means of comprehensive image analysis. With the proposed approach, the attached residual mortar can be adequately removed, and the residual mortar content can be determined.
Continuous Improvement of the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED®) Rating System™
Authors: Todd Joel Ann , Boecker John 
Published: December 2007

Abstract
The U.S. Green Building Council’s (USGBC) Leadership in Energy and Environmental Design (LEED) Rating System™ has had a significant impact on the market in the United States and is beginning to affect markets around the world. First launched in the late 1990s, LEED has undergone periodic revision, including updates as well as addition of new versions that address different markets and enhance technical quality of the credits. In 2006, the USGBC initiated a continuous improvement process that will result in a LEED system that is more technically robust and easier to use. This paper describes improvements that are underway using a proposed framework for analyzing green building rating systems. This framework encourages a broader and deeper analysis of rating systems, looking beyond the technical metrics to include the purpose and goals of the system, the context in which it is applied, the scope of the system, the metrics, and the processes used in its implementation.