cssi/SciSciGPT-SciSciNet huggingface dataset:
Determinants of carboxyl-terminal domain translocation during prion protein biogenesis.

Abstract The prion protein (PrP) displays some unusual features in its biogenesis. In cell-free systems it can be synthesized as either an integral transmembrane protein spanning the membrane twice, with both amino and carboxyl domains in the lumen of the endoplasmic reticulum, or as a fully translocated polypeptide. A charged, extracytoplasmic region, termed the Stop Transfer Effector (STE) sequence, has been shown to direct the nascent translocating chain to stop at the adjoining hydrophobic domain to generate the first membrane-spanning region (TM1). However, the determinants of the second translocation event in the biogenesis of the transmembrane form have not been identified previously. Moreover, the relationship of transmembrane and fully translocated forms of PrP has not been well understood. Here, we report progress in resolving both of these issues. Using protein chimeras in cell-free translation systems and Xenopus oocytes, we identify the sequence which directs nascent PrP to span the membrane a second time, with its carboxyl-terminal domain in the endoplasmic reticulum lumen. Surprisingly, PrP carboxyl-terminal domain translocation does not appear to be directed by an internal signal or signal-anchor sequence located downstream of TM1, as would have been expected from studies of other multispanning membrane proteins. Rather, carboxyl-terminal domain translocation appears to be another consequence of the action of STE-TM1, that is, the same sequence responsible for generating the first membrane-spanning region. Studies of an STE-TM1-containing protein chimera in Xenopus oocytes demonstrate that most of these chains upon completion of their translation, initially span the membrane twice, with a topology similar to that of transmembrane PrP, but are carbonate-extractable. These chains have the transmembrane orientation only transiently and chase into a fully translocated form. These results support a model in which a metastable "transmembrane" intermediate, residing within the aqueous environment of the translocation channel, can be converted into either the integrated transmembrane or the fully translocated form of PrP, perhaps directed by trans-acting factor (s). Such a model may explain why stable the transmembrane isoform of PrP has not been observed in normal cells and how nascent PrP might be directed to alternate pathways of folding.
Merger Strategies as a Response to Bilateral Market Power

Merger behavior is explored within the framework of the desire to manage resources and market dependencies. It is argued that market power resides in the bilateral relationships between buyer and s...
Synthesis of oxalyl phosphate and processing of the acyl phosphate by phosphoenolpyruvate-dependent enzymes.

Abstract The mixed anhydride of oxalic and phosphoric acids, oxalyl phosphate, has been prepared by reaction of oxalyl chloride and inorganic phosphate in aqueous solution. The product was purified by anion exchange chromatography and characterized by 31P and 13C NMR. This acyl phosphate has a half-life of 51 h at pH 5.0 and 4 °C. Oxalyl phosphate, an analogue of phosphoenolpyruvate, is a slow substrate for pyruvate kinase, undergoing an enzyme-dependent phosphotransfer reaction to produce ATP from ADP. Oxalyl phosphate substitutes for phosphoenolpyruvate in the reaction catalyzed by pyruvate, phosphate dikinase. The acyl phosphate reacts with the free enzyme to give the phosphorylated form of the enzyme. Removal of the potent product inhibitor, oxalate, from the reaction mixtures by gel filtration chromatography permitted further reaction of the phosphorylated enzyme with pyrophosphate and AMP to give ATP and Pi in a single turnover assay. Oxalyl phosphate also served as a phospho group donor in a partial reaction catalyzed by phosphoenolpyruvate carboxykinase wherein GDP is phosphorylated at the expense of oxalyl phosphate.
Controllable high-speed rotation of nanowires

We report a versatile method for executing controllable high-speed rotation of nanowires by ac voltages applied to multiple electrodes. The rotation of the nanowires can be instantly switched on or off with precisely controlled rotation speed (to at least 1800 rpm), definite chirality, and total angle of rotation. We have determined the torque due to the fluidic drag force on nanowire of different lengths. We also demonstrate a micromotor using a rotating nanowire driving a dust particle into circular motion. This method has been used to rotate magnetic and nonmagnetic nanowires as well as carbon nanotubes.
Eye protection from light radiation

It appears that green absorptive lenses are highly desirable for the purposes of shielding the eyes against light radiation from molten metal during the casting and soldering procedures. The dental laboratory technicians have experienced no after-images, less eye fatigue, and no adverse symptoms when using these lenses, as were reported previously. The lenses not only effectively protect the eyes from the injurious light wavelengths, but they also provide for enough normal (as well as individually corrected) vision to accomplish any procedure necessary in the dental laboratory. We propose that the green absorptive lenses, with individual corrections if needed, be considered for dental laboratory technicians during dental laboratory procedures when needed, such as during casting and soldering, to protect their eyes from light radiation. Language: en
Quinolone antibacterial agents for the treatment of genitourinary tract infections.

The fluoroquinolones have expanded the therapeutic options available for the treatment of genitourinary tract infections. Their ease of oral administration, favorable pharmacokinetics, low incidence of adverse reactions, and broad spectrum of in vitro activity against aerobic and facultative organisms make them especially suitable for treating bacteriuria, particularly when pathogens are resistant to other available oral agents. Their efficacy has also been established in the treatment of prostatitis, gonorrhea and chancroid. They have lower in vitro activity against chlamydia, ureaplasma and anaerobes, and their role in the treatment of non-gonococcal urethritis, vaginitis and acute pelvic inflammatory disease is less well established.
RGS14 is a multifunctional scaffold that integrates G protein and Ras/Raf MAPkinase signalling pathways.

Abstract MAPkinase signalling is essential for cell growth, differentiation and cell physiology. G proteins and tyrosine kinase receptors each modulate MAPkinase signalling through distinct pathways. We report here that RGS14 is an integrator of G protein and MAPKinase signalling pathways. RGS14 contains a GPR/GoLoco (GL) domain that forms a stable complex with inactive Giα1/3–GDP, and a tandem (R1, R2) Ras binding domain (RBD). We find that RGS14 binds and regulates the subcellular localization and activities of H-Ras and Raf kinases in cells. Activated H-Ras binds RGS14 at the R1 RBD to form a stable complex at cell membranes. RGS14 also co-localizes with and forms a complex with Raf kinases in cells. The regulatory region of Raf-1 binds the RBD region of RGS14, and H-Ras and Raf each facilitate one another's binding to RGS14. RGS14 selectively inhibits PDGF-, but not EGF- or serum-stimulated Erk phosphorylation. This inhibition is dependent on H-Ras binding to RGS14 and is reversed by co-expression of Giα1, which binds and recruits RGS14 to the plasma membrane. Giα1 binding to RGS14 inhibits Raf binding, indicating that Giα1 and Raf binding to RGS14 are mutually exclusive. Taken together, these findings indicate that RGS14 is a newly appreciated integrator of G protein and Ras/Raf signalling pathways.
Solid Phase Host−Guest Properties of Cyclodextrins and Calixarenes Covalently Attached to a Polysilsesquioxane Matrix

A new family of silicon-based polymers has been prepared with covalently bound hosts. The polymer is a polysilsesquioxane formed by the sol−gel process, and the hosts are cyclodextrins (CD) or calixarenes (CX). The organic and silicon structures are supported by solid-state NMR spectroscopy. The nanoporous polymer is relatively stable to a variety of aqueous conditions. It is a water-insoluble material, which binds with and extracts both organic compounds and metal cations from water. The polymer containing the guests is then removed by filtration. The objective achieved can be either removal of impurities from water or recovery of materials dissolved in water. The CD-based polymer may be renewed by treatment with ethanol. Its binding ability is equal or superior to that of other available materials such as activated charcoal.
The Influence of Image Motion and Shutter Operation on the Photographic Transfer Function

In Part I a general two-dimensional expression for the transfer function of the photographic exposure image is derived, including as factors the optical transfer function, the transfer function arising from scattering of light in the emulsion, the shutter function, and the motion of the image. The effect of shutter operation in the absence of image motion is discussed and it is shown that a focal-plane shutter acts as an independent agent with its own effective transfer function, whereas a between-the-lens shutter is not independent but acts as an apodizing agent. In Part II, the effect of image motion is discussed, with the assumption that the optical transfer function is independent of the shutter action. The concept of an equivalent spread function for image motion is developed, and uniform linear image motion and harmonic image motion are discussed in detail, the latter especially for the case where there are at simple the most only a few periods in the exposure time. An approximation for small degradations is then obtained in which all possible combinations of uniform linear motion and simple harmonic motion are contained. Throughout the paper the functions discussed are functions of two-dimensional space.
Diversity in Higher Education: The Three Rs

Research indicates that a diverse student body is beneficial for education. The Association to Advance Collegiate Schools of Business (AACSB) accreditation standards also include a commitment to diversity. In California, as well as in some other states, preferential treatment in admissions to bring about a diverse student body is against the law, which may be problematic for some universities (Golden, 2003). Many schools have struggled with this dilemma of developing diversity in the campus population. In this article, the authors examine diversity in the student body, and the role of recruitment, retention, and relationship building. The authors propose a conceptual model for successfully enhancing student diversity. They also present the implementation of the model developed at a California university and discuss the benefits of the study to the students as well as the employers.
On a modification of Marquardt's compromise: Rationale and applications

The method of Marquardt's compromise for handling the problem of near-singularity in nonlinear regression is modified by (a) utilizing methods from ridge regression for computing the Marquardt parameter k, and (b) utilizing a search method of interpolation-extrapolation for determining the step size. The performance of these modifications is evaluated on a number of standard test problems from the literature. It is shown that the Lawless-Wang estimate of k without the benefit of interpolation- extrapolation competes favorably with standard algorithms implemented in packaged programs. An application to a model of plasma insulin dynamics is also given. Comparison of the modified procedure with the Nelder-Mead simplex method is given.
Harmonic wave propagation in materials with periodic beam-structure

Abstract The characteristics of harmonic waves propagating in periodic beam structures are investigated. For this purpose, a very effective method for the calculation of dispersion relations of elastic waves in these materials is developed by applying dynamic theory of crystal lattices to discrete models of periodic beam structures. This method is applicable to general three-dimensional periodic beam structures. Results presented show that the solutions converge to the exact solution as the number of atoms in the discrete models increases. The dispersion relations of plane harmonic waves in the micropolar continuum model, developed in a previous study, are also calculated. They are compared with the exact solutions to examine the applicability of the continuum models to dynamic problems.
Development of monolithic CMOS detectors as x-ray imaging spectrometers

We present preliminary results from our ongoing program to develop CMOS detectors as single photon counting, soft X-ray imaging spectrometers. The Smithsonian Astrophysical Observatory in collaboration with SRI International/ Sarnoff has been developing monolithic CMOS detectors optimized for x-ray astronomy. Our latest detector consists of an array of 1k × 1k 16 μm pixels manufactured on 15μm epitaxial Si. These detectors are designed to be packaged and thinned for back illumination. The devices have on-chip CDS and are optimized to have high (~ 40 frame/sec) read-out rates. Such monolithic CMOS imaging sensors would be ideal candidate detectors for the focal planes of space-borne soft x-ray astronomy missions. The high through-put, low noise and excellent low energy response, provide high dynamic range and good time resolution; bright and time varying x-ray features could be temporally and spectrally resolved without saturation or photon pile-up.
The cost of eigenvalue computation on distributed-memory MIMD multiprocessors

Abstract In [20], Simon proves that bisection is not the optimal method for computing an eigenvalue on a single vector processor. In this paper, we show that his analysis does not extend in a straightforward way to the computation of an eigenvalue on a distributed-memory MIMD multiprocessor. In particular, we show how the optimal number of sections (and processors) to use for multisection depends on variables such as the matrix size and the ratio of communication and computation costs. We also show that parallel multisection outperforms the variant of parallel bisection called polysection proposed by Swarztrauber in [22] for this problem on a distributed-memory MIMD multiprocessor. We present the results of experiments on the 64-processor Intel iPSC/2 hypercube and the 512-processor Intel Touchstone Delta mesh multiprocessor.
Multistatic polarimetric radar data modeling

Multistatic and polarimetric radars are two active areas of research. Polarimetric radar systems collect more information about an environment than if a single polarization is used, despite the historically prohibitive cost of these systems. Similarly, multistatic systems have a number of theoretical advantages, including 1) the ability to transmit multiple waveforms from collocated or distributed antennas, thus enabling interrogation of larger areas of interest due to the geometry of the system and 2) the possibility of augmenting fielded systems with additional low-power passive components. The design of a multistatic system, however, requires many decisions regarding the number, geometry, and polarization of the transmitters and receivers, and the waveforms that will be transmitted from each transmitter. These decisions will depend on the environment and targets of interest.
The use of Raman spectroscopy to characterize double B/Z conformational junctions in DNA

Abstract Raman spectra of the duplex of the self-complementary oligodeoxynucleotide, d[TTCGCGCGCGAA] at various salt concentrations and temperatures have been acquired. Two methods are described which indicate that the intensities of the bands at 680 cm −1 and 625 cm −1 can be analyzed using the band assignments of Tsuboi, Nishimura and colleagues to determine the relative number of CG base pairs in the Z form. The absence of bands characteristic of AT base pairs in the Z form rules out the occurrence of the Z form in the AT portion of the duplex. From these measurements the structure of the double helical duplex in concentrated salt solutions can be described as having four of the six interior CG base pairs in Z form flanked by two CG base pairs in the junction and the two AT base pairs in a short B-form segment.
Purificatio of a specific d-apiitol dehydrogenase from a Micrococcus isolated from the surface of germinating parsley seeds

The branched-chain sugar d-apiose was oxidized to CO2 by both Lemma minor and a bacterium which was isolated from the surface of germinating parsley seeds. An inducible dehydrogenase which catalyzed the interconvension of d-apiose and d-apiitol was detected in extracts of this microorganism. The enzyme which was purified about 200-fold was specific for d-apiose and d-apiitol. It oxidized myo-inositol and meso-erythritol slowly, but it was completely inactive with all of the other sugars and polyols tested. The enzyme was specific for NAD+ and NADH as electron acceptor and donor, respectively. NADP+, NADPH, ascorbate, FAD, FADH2, cytochrome c and ferricyanide were inactive. The Km for D-apiitol was 1.16·10-2 M, d-apiose was 7.14 · 10−2 M, NAD+ was 3.5 · 10-4 M and NADH was 1.5–15-5 M. At high concentrations NADH inhibited the reaction. The molecular weight of the dehydrogenase determined by chromatography on Sephadex 200 and sucrose density centrifugal was 110 000. The products of the reaction were characterized by paper chromatography, periodate oxidation and gas chromatography of acetylated derivatives. A colorimetric method for the quantitative determination of small amounts of d-apiose was also developed during the course of this study.
TeraNet: a multigigabit-per-second hybrid circuit/packet-switched lightwave network

TeraNet is an experimental optical network which offers user access rates as high as one Gigabit per second (Gbps). The network provides both circuit switching and ATM packet switching in a hierarchical fashion. Circuit switching is accomplished through the use of tunable optical WDMA/Subcarrier-FDMA channels. An overlaid multihop technique that uses a sub-set of the underlying optical circuits, constructs a packet switching environment. Circuit switched services interface to the passive optical 'ether' through Media Interface Units (MIU). A 3 X 3 switching node called Network Interface Unit (NIU), with 1 Gbps capacity per port, is used as an ATM access port to the packet switching layer. The ATM overlaid network incorporates a traffic control architecture that supports multiple traffic classes. Output buffers and bandwidth are shared according to a resource allocation concept called Asynchronous Time Sharing (ATS).
Pudendal motor and premotor neurons in the male rat: a WGA transneuronal study.

Anatomical studies using retrograde neuronal tracers were carried out to identify pudendal motoneurons and putative lumbosacral interneurons involved in the generation of penile reflexes in the adult male rat (Sprague-Dawley). In agreement with previous studies, injection of the direct neuronal tracers, horseradish peroxidase or fluoro-gold, into the left M. bulbospongiosus (dorsal division) resulted in direct retrograde labeling of motoneurons only in the ipsilateral dorsomedial (DM) nucleus. In contrast, similar injections of the transneuronal tracer, wheat germ agglutinin (WGA), resulted in direct retrograde labeling of ipsilateral DM motoneurons as well as transneuronal labeling of contralateral DM motoneurons and of bilaterally located putative spinal interneurons. The WGA-labeling was determined to be transneuronal by a series of nerve cut experiments. The direct retrograde WGA-labeling of ipsilateral DM motoneurons and the transneuronal WGA-labeling of contralateral DM motoneurons and bilateral putative spinal interneurons occurred with different time courses. Direct retrograde labeling of ipsilateral DM motoneurons was seen at 20 hours survival and persisted up to 7 days survival. The shortest survival period for detecting transneuronal labeling of contralateral DM motoneurons and putative interneurons was 2 days. Transneuronal WGA-labeling of contralateral DM motoneurons was transient in that the intensity of label increased from 2 to 3 days survival but was markedly reduced at 7 days survival. At the same time, the number of WGA-labeled putative interneurons increased with longer survival times up to 7 days. WGA-labeled putative interneurons were located primarily in regions receiving dendritic projections from WGA-labeled DM motoneurons and, in particular, (1) the ventral gray matter between the DM and dorsolateral nuclei and (2) near the central canal and extending dorsally to the dorsal gray commissure. The rapid and extensive transneuronal transport between DM nuclei suggests that direct synaptic coupling may mediate coordinated, bilateral activation of DM motoneurons.
Predator-induced delayed maturity in bluegill sunfish (Lepomis macrochirus): variation among populations

Previous studies suggested that differences in age at maturity among populations of bluegill sunfish (Lepomis macrochirus) were not genetically based, but rather were a phenotypic response to the presence of predators. I conducted two experiments to determine if the presence of largemouth bass affected age at maturity in bluegill sunfish. Bluegills from three populations were tested to see if the response to the threat of predation varied among source populations. Juvenile bluegills were maintained in the presence of predators or in controls with no contact with predators. Refuge use and growth were monitored during the experiments and reproductive activity was evaluated when bluegills reached age 1. Bluegills from one population exhibited delayed maturity in the presence of predators. Individuals from the other two populations showed no significant differences between predator and control treatments. The population that responded to the presence of predators had a history of high predation levels over the past 30–40 years. The other populations had a history of low levels of predation. This study suggests that presence of predators can induce phenotypic shifts in age at maturity of bluegills, but that the magnitude of response varies among populations in a manner consistent with historical patterns of coexistence.
Effect of strain and electric field on the electronic soft matter in manganite thin films

We have studied the effect of substrate-induced strain on the properties of thin films of the hole-doped manganite ${({\mathrm{La}}_{1\ensuremath{-}y}{\mathrm{Pr}}_{y})}_{0.67}{\mathrm{Ca}}_{0.33}\mathrm{Mn}{\mathrm{O}}_{3}$ ($y=0.4$, 0.5, and 0.6) grown on $\mathrm{Nd}\mathrm{Ga}{\mathrm{O}}_{3}$ (NGO) substrates, in order to distinguish between the roles played by long-range strain interactions and quenched atomic disorder in forming the micrometer-scale phase separated state. We show that a fluid phase separated (FPS) state is formed at intermediate temperatures similar to the strain-liquid state in bulk compounds, which can be converted to a metallic state by applying an external electric field. In contrast to bulk compounds, at low temperatures a strain stabilized ferromagnetic metallic (FMM) state is formed in the $y=0.4$ and 0.5 samples. However, in the $y=0.6$ sample a static phase separated (SPS) state is formed similar to the strain-glass phase in bulk compounds. Our results suggest that the substrate-induced strain is a function of temperature. Hence, we show that the temperature induced variation of the long-range strain interactions plays a dominant role in determining the properties of thin films of phase-separated manganites.
The Ballistocardiogram in Juvenile Diabetes Mellitus

Ballistocardiographic studies were made in 41 patients; with diabetes since childhood. A high incidence of abnormalities was observed. The possible diagnostic and prognostic implications are discussed.
Clostridium bartlettii sp. nov., isolated from human faeces

Seven obligately anaerobic, Gram-positive, rod-shaped, spore-forming organisms isolated from human faecal specimens were characterized using phenotypic and molecular taxonomic methods. Strains of the unidentified bacterium used carbohydrates as fermentable substrates, producing acetic acid, isovaleric acid and phenylacetic acid (PAA) as the major products of glucose metabolism, and possessed a G +C content of approximately 29.8 mol%. Comparative 16S rRNA gene sequencing showed that the 7 strains were genetically highly related to each other (displaying >99.5% sequence similarity) and represent a previously unknown sub-line within the Clostridium Cluster XI. The closest described species to the novel bacterium is Clostridium glycolicum, although a 16S rRNA sequence divergence of 4% demonstrates that they represent different species. Genomic DNA-DNA pairing studies confirmed the separateness of the unknown species and C. glycolicum (30.6% similarity between the proposed type strain of the novel species, WAL 16138, and C. glycolicum ATCC 14880(T)). Based on morphologic, phenotypic and phylogenetic evidence, it is therefore proposed that the unknown bacterium be classified as C. bartlettii sp. nov. The type strain of C. bartlettii is WAL 16138(T) (= ATCCBAA-827(T)=CCUG48940(T)).
Efficiently evaluating reachable sets in the circular restricted 3-body problem

In space mission trajectory planning in dynamic environments, such as at asteroids, scenarios leading to failure must be discovered. Given an initial state of a spacecraft about an asteroid, failure can be simply quantified as impact of the vehicle with the asteroid or escape of the vehicle from the asteroid. For mission planning and execution purposes it is necessary to perform maneuvers to avoid such outcomes, however the overall set of possible maneuvers that either avoid impact or escape can be a complex set that cannot be analytically characterized. This paper introduces a reachable set explorer (RSE) for exploring the reachable set of a spacecraft—the set of trajectories under a range of ΔV expenditures. This approach is applied to the circular restricted 3-body problem (CR3BP) where a brute-force approach is intractable. RSE focuses on the boundaries between impact, escape, and in-system regions, known as the end-result regions.
Influence of time off feed on broiler viscera weight, diameter, and shear

Abstract The influence of time off feed on broiler viscera weight, intestinal diameter, and shear was studied by subjecting market-age male broilers (42, 44, or 48 d) to incremental feed withdrawal periods (0, 6, 12, 18, or 24 h). Body weight was determined prior to feed withdrawal and at the time of processing. After slaughter, scalding, and defeathering, the abdominal cavity was opened. Diameter and shear of the proventriculus-ventriculus junction, jejunum, and ileum segments were measured, as were gallbladder length and width. Thoracic and abdominal viscera, liver, and ventriculus weights were determined, and liver surface color was measured. Percentage body weight loss increased with longer feed withdrawal periods, as viscera, liver, and ventriculus weights decreased. Gallbladder length increased with time off feed, whereas its width did not change. Diameter of the proventriculus-ventriculus junction, jejunum, and ileum decreased with longer feed withdrawal periods. Shear values for the proventriculus-ventriculus junction, jejunum, and ileum were not influenced by time off feed. Positive correlations (P 0.4) between viscera weight and intestinal diameter were detected. Correlations between all measured parameters and shear values were not significant. Liver color measurements indicated that longer feed withdrawal periods resulted in significant linear decreases in L* (lightness), +a* (redness), and +b* (yellowness). Longer feed withdrawal periods decreased viscera weight and intestinal diameter, which would lower the potential for cutting the intestine during automated evisceration. However, the resulting greater gallbladder length (5 mm) would increase the possibility of bile contamination during evisceration.
Blood glucose, total serum cholesterol and total bilirubin levels of rats following extraintestinal migration of Strongyloides venezuelensis (Brumpt, 1934).

Abstract 1. 1. Blood glucose, total serum cholesterol and total bilirubin levels of rats were determined during the tissue migration of the third stage larva of Strongyloides venezuelensis. 2. 2. The blood glucose level of the infected rats significantly decreased at 12 and 72 hr post inoculation while the parasite is in the heart and lungs and significantly increased at 24 and 48 hr post inoculation when the parasite is in the liver. 3. 3. Total serum cholesterol levels in the infected rats were significantly different at 12, 24, 48 and 72 hr post inoculation while the parasite is associated with the liver and limbs. 4. 4. Total bilirubin levels were significantly different in the infected group from 24 to 96 hr post inoculation when the parasite is in the liver. 5. 5. No significant differences in the examined physiological levels of the two experimental groups were determined following the completion of the tissue migration phase of the parasite.
The Idea of Covenant and American Democracy

Every effort to deal with the history of ideas is beset by hazards. Semantic traps are strewn along the way of the inquirer; such words as democracy, liberty, justice, etc., point to different concepts or varying complexes of concepts as they are used in different periods of history and by different men. The unuttered and frequently unacknowledged presuppositions of those who employ them also vary; and since meaning largely depends on context the difficulties of understanding what is meant are increased by the difficulty of ascertaining what is at the back of the minds.
Drag reduction of a noncircular missile by base burning

Introduction I N a series of experiments on supersonic base flows, Barr discovered a complex flow pattern in a V-shaped channel attached to a back step. This flow pattern resulted whenever a uniform supersonic flow passing over a back step separated and reattached in the bottom of a v channel. A flow model based on detailed studies of Zumwalt suggests that, in the process of reattachment, the shear layer emanating from the back step moves down into the corner, squeezes by the converging walls, and rolls its edges, and as a result, the vorticity vector gets aligned with the dominant direction of the flow (Fig. 1). In the bottom of the v channel, these counter-rotating vortices stay submerged in the outer flow. The effects of this vortex pair were observed not only downstream but also upstream into the near-wake region reaching almost to the back step. Zumwalt also observed that one of the vortices slips under the other and they lie asymmetrically in the bottom of the v channel. Friedberg and Ahmed later furthered the studies and found that these vortices were very stable and resulted in high levels of mixing when a secondary gas was injected in the base region. These vortices also increased the residence time and, therefore, offered a unique environment for sustained burning of hydrogen when injected in the base region of a back step. In addition, they also observed that the base pressure increased considerably in the presence of the v channels suggesting that the flow phenomena was a possible mechanism for the bleeding of higher pressure from the reattachment point to the base region. In a subsonic flow regime, base flow is dominated by periodic formation and shedding of eddies in the wake; the base pressure is low, indicating high drag. With an increase in flow velocity, base pressure tends to decrease. However, for a given flow velocity and step height, it tends to remain uniform except when additional mass flow is injected into the separated region or when there is a temperature rise due to combustion. This increase in base pressure in turn lowers the base drag which is defined as,
Density-functional approximation for the correlation energy of the inhomogeneous electron gas

Langreth and Mehl (LM) and co-workers have developed a useful spin-density functional for the correlation energy of an electronic system. Here the LM functional is improved in two ways: (1) The natural separation between exchange and correlation is made, so that the density-gradient expansion of each is recovered in the slowly varying limit. (2) Uniform-gas and inhomogeneity effects beyond the randomphase approximation are built in. Numerical results for atoms, positive ions, and surfaces are close to the exact correlation energies, with major improvements over the original LM approximation for the ions and surfaces.
Sacroiliac kinematics for reciprocal straddle positions

Study Design. A descriptive and correlation approach was used to assess joint motion. Objectives. Magnitudes and directions of sacroiliac motion were examined from three different upright postural conditions. Summary of Background Data. Evidence and clinical views suggest that sacroiliac motion available in the normal case is extremely small to nonexistent. Methods. Systems for standardizing the three postures and the Metrecom skeletal analysis system (Metrecom, Faro Technologies, Inc., Lake Mary, FL) for acquiring coordinate data for selected skeletal landmarks. Results. The complete sacroiliac oblique-sagittal motion that occurred between the right forward and left forward stride positions was 9° (SD 6.5). The composite oblique-transverse motion was 5° (SD 3.9). The motions in each plane were significantly different from zero. A joint mobility relationship existed between the hip and sacroiliac joints. Conclusion. The results demonstrate that substantial angular motion is possible at the sacroiliac joints.
Seeing the futures: profiling shared-memory parallel racket

This paper presents the latest chapter in our adventures coping with a large, sequentially-tuned, legacy runtime system in today's parallel world. Specifically, this paper introduces our new graphical visualizer that helps programmers understand how to program in parallel with Racket's futures and, to some extent, what performs well in sequential Racket.Overall, our experience with parallelism in Racket is that we can achieve reasonable parallel performance in Racket without sacrificing the most important property of functional programming language implementations, namely safety. That is, Racket programmers are guaranteed that every Racket primitive (and thus all functions built using Racket primitives) will either behave properly, or it will signal an error explaining what went wrong.That said, however, it is challenging to understand how to best use futures to achieve interesting speedups, and the visualizer is our attempt to more widely disseminate key performance details of the runtime system in order to help Racket programmers maximize performance.
Redescription of Anomalosaepia (Cephalopoda: Coleoida): A Sepioid with a Bimineralic Calcite and Aragonite Skeleton

Abstract Redescription of the genus Anomalosaepia shows that the anomalous characters reported as defining the genus are partly preservational artifacts resulting from dissolution of aragonite from a skeleton composed of both calcite and aragonite. Thus, the presence of a slit-shaped opening and canal-like cavity in the skeleton is not supported. The skeleton of Anomalosaepia is composed of subequal amounts of aragonite and calcite, with an inner layer composed of radial-prismatic and fan-radial aragonite and an outer layer of elongate, non-prismatic calcite crystals secreted by the animal. The calcite microstructure has not been previously described. A new family, Anomalosaepiidae, is established and one new species, A. parmula, described. The species A. mariettani and A. andreanae are synonomized with A. alleni. The species A. jeletzkyi is valid and A. vernei is probably valid, but needs more documentation. Examination of North American and European specimens reveals that a bimineralic composition is a ...
Nitric Oxide in Endothelial Dysfunction and Vascular Remodeling: Clinical Correlates and Experimental Links

The patency of the vascular system is essential to maintain normal tissue function. Fortunately for us, the genetic program of vascular cells (endothelial cells,smooth muscle cells, and fibroblasts) endows them with the capacity to respond to physiological and pathophysiological stimuli and to rearrange their architecture to maintain adequate blood flow according to the metabolic demand of the tissue. Rapid calibration of lumen diameter can occur through vasomotor controlgoverned by the sympathetic nervous sytem and vasoactive factors. Long-term structural adaptation, perhaps reflecting the summation of many short-term vasomotor events, occurs through a process called “vascular remodeling.” Vascular remodeling is the ability of the vessel wall to reorganize its cellular and extracellular components in response to a chronic stimulus (Gibbons and Dzau 1994). Experimental studies have shown that increases in blood flow due to an arteriovenous shunt will increase vessel diameter; conversely, reductions in blood flow will reduce vascular diameter. On the basis of these findings, it is believed that chronic reduction in blood flow initiates a signaling cascade that leads blood vessels to contract acutely and remodel themselves, creating a smaller vascular lumen. This remodeling reduces the shear stress and the circumferential wall strain imposed by the lower flow rates (Kamiya and Togawa 1980; Langille and O’Donnell 1986). The layered structure of the vascular system facilitates information transfer from the lumen of the vessel into the underlying smooth muscle and then to surrounding tissue. Likewise, the vessel responds to neural input and tissue factors to influence the smooth muscle and the endothelium.Thepositionofthevascular
Multilayer coatings for corrosion protection of coal gasifier components

Abstract Deposition of TiAlN/Nb, TiAlN/Ta, TiAlN/W and TiAlN/Zr multilayer coatings on 409 stainless steel was studied by CVD in a fluidized bed reactor (FBR-CVD). The coatings consisted of four TiAlN layers with individual thickness of 2.5–3.5 μm, and four metal interlayers with thicknesses in the range of 100–250 nm. The W interlayers suffered partial nitridation during the coating process and the resulting coatings had poor adhesion. Deposition of Zr through reduction of ZrI4 by H2 was found to be inefficient. Both TiAlN/Nb and TiAlN/Ta coatings showed good adhesion, but only TiAlN/Nb provided sulfidation resistance to 409 steel during exposure to simulated coal gas at 1173 K for 300 h. Though outward diffusion of Cr took place during the corrosion test, the results reported in this paper suggest that TiAlN/Nb coatings are promising candidates for corrosion protection of steels under typical coal gasifier conditions.
Self-stabilizing iterative solvers

We show how to use the idea of self-stabilization, which originates in the context of distributed control, to make fault-tolerant iterative solvers. Generally, a self-stabilizing system is one that, starting from an arbitrary state (valid or invalid), reaches a valid state within a finite number of steps. This property imbues the system with a natural means of tolerating transient faults. We give two proof-of-concept examples of self-stabilizing iterative linear solvers: one for steepest descent (SD) and one for conjugate gradients (CG). Our self-stabilized versions of SD and CG require small amounts of fault-detection, e.g., we may check only for NaNs and infinities. We test our approach experimentally by analyzing its convergence and overhead for different types and rates of faults. Beyond the specific findings of this paper, we believe self-stabilization has promise to become a useful tool for constructing resilient solvers more generally.
Quality Improvement in Respiratory Care: Decreasing Bronchopulmonary Dysplasia

Chronic lung disease (CLD) is one of the most common long-term complications in very preterm infants. Bronchopulmonary dysplasia (BPD) is the most common cause of CLD in infancy. Modern neonatal respiratory care has witnessed the emergence of a new BPD that exhibits decreased fibrosis and emphysema, but also decreased alveolar septation, and microvascular development. CLD encompasses the classic and the new BPD, and recognizes that lung injury can occur in term infants who need aggressive ventilatory support and who develop lung injury as a result, and that CLD is a multisystem disease. Controversy exists on whether quality improvement (QI) methods that implement multiple interventions will be effective in limiting pathology with multiple causes. Caution in generalization of QI findings is encouraged. QI methods toward improvement in CLD or any other outcome should be considered as a tool for implementing evidence and studying the effects of change in complex adaptive systems.
Evaluation of chronic wrist pain by arthrography, arthroscopy, and arthrotomy

Abstract Arthrography and arthroscopy of the wrist were compared as diagnostic tools in the evaluation of chronic wrist pain. Arthroscopy proved to be a more sensitive procedure than arthrography in 20 consecutive patients with confirmed wrist injuries. There was 86% correlation (the exception—one false negative arthroscopic procedure) between arthroscopy and arthrography in eight patients with triangular fibrocartilage tears. Compared with arthroscopy, there were five false negative and five false positive arthrograms when evaluating interosseous scapholunate and lunotriquetral ligament tears. Arthroscopy more readily identified the location and extent of triangular fibrocartilage and the significance of interosseous ligament tears. Wrist arthrotomy confirmed the findings of wrist arthrography and arthroscopy and demonstrated that arthrography is not as accurate in localizing specific wrist injuries. Furthermore, wrist arthroscopy is a more valuable technique in determining the location, size, and extent of ligament injuries within the wrist.
Modeling multiple-layer piezoelectric actuators in active structural control

ABSTRACT The design and analysis of finite length multiple layered induced strain actuators to further extend the application of piezoeleciric actuators in active structural control is investigated. A model of an arbitrary surface bonded multiple layered actuator is utilized to predict the applied force and moment of the 1tI piezoelectric layer on a beam. The equations of motion for the transverse vibration of a simply supported beam are derived using Timoshenko beam theory and cast in state space form. The forced response of the one dimensional actuator/substructure system to the piezoelectric induced loads isobtained using an assumed mode technique. The results of experiments performed on a simply supported beam, using various multiple layer piezoelectric actuator configurations for excitation, are compared to analytical predictions for modelverification. 1. INTRODUCTION In recent years the use of piezoelectric materials in active structural vibration and acoustic control, in both sensing and
Agglutinating antibodies in the sera of chickens with regressing Rous sarcomas.

SEVERAL antigens specific for tumour cells have been identified1–7 in tumours induced by viruses, and virus-induced resistance to tumour cell antigens has been established8–11. It now seems important to investigate surface tumour cell antigens because they may be involved in the induction of resistance. I have studied the surface cell antigens of chicken sarcomas induced by the Rous virus (Carr–Zilber strain), using sera from adult chickens in which tumours, induced by the virus or by transplanted tumour cells, had regressed after an initial period of active growth. Regression was most frequent in chickens inoculated with low doses of virus or tumour cells. The sera were heated at 56° C for 30 min and added to a cell suspension prepared from chicken Rous sarcoma. The suspension contained 2 × 107 cells/ml. Sera taken from intact healthy chickens were used as a control. The mixtures of cells and immune or control sera were kept at 4° C for 18 h. The reaction was checked under the microscope (magnification × 120). Table 1 shows that of thirteen sera taken from chickens in which the tumours had regressed, nine produced agglutination of tumour cells (Fig. 1). Sera from fifteen control chickens and twenty-five chickens with actively growing sarcomas showed no agglutinating activity. Agglutinating antibodies appeared in the blood at the time of tumour regression arid remained there in some cases for a period of 60–105 days after regression. Our stock of chickens was not inbred so it was necessary to find whether immune sera would also agglutinate normal chicken cells. Sera were therefore added to a cell suspension prepared from the spleen, liver, thymus and bursa of Fabricius of untreated chickens. Immune sera also agglutinated normal chicken cells. These results show that the antibodies, or at least some of them, were isoantibodies directed against the isoantigens of tumour and normal tissue.
Power Coefficient of Tornado-Type Wind Turbines

In a tornado-type wind turbine the wind collecting tower is equipped with adjustable vanes that can be opened on the windward side and closed on the leeward side. The wind enters the tower tangentially through these open vanes and exits from the top. As a result, a vortex is formed inside the tower. A vertical axis turbine which is located underneath the tower floor admits air vertically and exhausts it into the vortex core. The pressure drop in the vortex core can be high, depending upon the vortex concentration, thus enhancing manyfold the total pressure drop across the turbine. The power coefficient C /SUB p/ of this system depends mainly on how low a pressure can be created in the vortex core. A maximum C /SUB p/ of about 2.5 was obtained by Yen for a spiral shaped tower. This is about 6.25 times the C /SUB p/ of conventional windmills. Analytical studies have been carried out by several investigators to study the C /SUB p/ of this vortex machine. Loth considered the conservation of angular momentum and obtained a C /SUB p/ based on the tower frontal area, which is not impressive.
SOCIAL: A Self-Organized Entropy-Based Algorithm for Identifying Communities in Networks

The identification of communities in complex networks is important to many fields including medicine, social science, national security, and marketing. A community structure facilitates the identification of hidden relations in networks that go beyond simple topological features. Current detection algorithms are centralized and scale very poorly with the number of nodes and edges present in the network. The use of these algorithms is prohibitive when applied to large-scale networks. In this paper, we propose a Self-Organized Community Identification Algorithm (SOCIAL) based on local calculations of node entropy that enables individual nodes to independently decide the community they belong to. In our context, node entropy is defined as the individual node's satisfaction with its current community. As nodes become more ``satisfied'' (entropy decreases) the community structure of a network emerges. Our algorithm offers several advantages over existing approaches including near-linear performance, identification of community overlaps, and localized management of dynamic changes in the network.
Observation of Intrinsically Localized Modes in a Discrete Low-Dimensional Material

We report the experimental observation of intrinsic dynamically localized vibrational states in crystals of the highly nonlinear halide-bridged mixed-valence transition metal complex ${[\mathrm{Pt}(\mathrm{en}{)}_{2}][\mathrm{Pt}(\mathrm{en}{)}_{2}{\mathrm{Cl}}_{2}]({\mathrm{ClO}}_{4}{)}_{4}}$, where $\mathrm{en}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\mathrm{ethylenediamine}$. These states are identified by the distinctive structure and strong redshifts they impose upon the overtone resonance Raman spectra. Quantitative modeling of the observed redshifts is presented based on a nonadiabatic coupled electron-lattice model that self-consistently predicts strong nonlinearity and highly localized multiquanta bound states.