cssi/SciSciGPT-SciSciNet huggingface dataset:
Measuring in vivo ureagenesis with stable isotopes.

Stable isotopes have been an invaluable adjunct to biomedical research for more than 70 years. Indeed, the isotopic approach has revolutionized our understanding of metabolism, revealing it to be an intensely dynamic process characterized by an unending cycle of synthesis and degradation. Isotopic studies have taught us that the urea cycle is intrinsic to such dynamism, since it affords a capacious mechanism by which to eliminate waste nitrogen when rates of protein degradation (or dietary protein intake) are especially high. Isotopes have enabled an appreciation of the degree to which ureagenesis is compromised in patients with urea cycle defects. Indeed, isotopic studies of urea cycle flux correlate well with the severity of cognitive impairment in these patients. Finally, the use of isotopes affords an ideal tool with which to gauge the efficacy of therapeutic interventions to augment residual flux through the cycle.
The Ebb and Flow of Nutrition as a Public Policy Issue

Recently, Cook (2) has described and em­ pirically validated a fourth model, the con­ vergent voice model. In this model, issues that seem to be independently and similarly articulated by several different groups at the same time may be then legitimatized through survey data, media attention, dis­ cussion by high government officials, and endorsement by appropriate interest groups. After having gained public visibi­ lity, the issue then becomes the focus for ac­ tual governmental action through the enact-" ment of legislation or other program ini­ tiatives. In this model Cook has identified four major stages. Figure 1 shows the rela­ tionship between these four stages of agenda setting and the emergence of hunger
Spatial and Chronological Patterns of Purshia Tridentata as Influenced by Pinus Ponderosa

Rodent caching is a significant factor in the establishment of Purshia tridentata in central Oregon pine forest. The pattern of cache placement is strongly influenced by pine litter patterns. As litter accumulates because of fire exclusion, desirable litter—free sites are becoming less abundant. As a result, a decline in Purshia populations may be expected. See full-text article at JSTOR
Radical copolymerization of 2‐trifluoromethylacrylic monomers. I. Kinetics of their copolymerization with norbornenes and vinyl ethers as studied by in situ 1H NMR analysis

Radical copolymerizations of electron-deficient 2-trifluoromethylacrylic (TFMA) monomers and electron-rich norbornene derivatives and vinyl ethers with azobisisobutyronitrile were investigated by analyzing the kinetics in situ with 1H NMR. Although none of the monomers underwent radical homopolymerization under normal conditions, they copolymerized readily, producing a copolymer containing 60–70 mol % TFMA. Terpolymerization involving these monomers was also investigated. The rates of copolymerization and kinetic chain lengths were determined in some cases on the basis of the in situ kinetics analysis. These radial copolymerizations of TFMA provide a basis for the preparation of chemical-amplification resist polymers for emerging 157-nm lithography. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1468–1477, 2004
Fracture failure modes in lightweight bearings

Rolling contact bearings fail in a wide variety of different modes. A fracture mode of failure becomes a possibility when operating with significant tensile hoop stress in the races. A series of sixteen bearings operated with tensile stresses in the races were analyzed for cracks. Ten of the sixteen bearings generated cracks of critical size resulting in rapid fracture of the races. From these data, an estimate is made of the critical stress intensity factor for AISI 52100 and AISI M-50, the materials currently used in aircraft engine bearings. Flaws are generated in the races apparently due to a combination of tensile hoop stress and the superimposed Hertz stress pattern. An attempt was made to correlate the flaw size and shape to the known stress fields, or components of the stress fields, but currently these have not been completely successful. Using relatively simple, established fracture mechanic techniques, a limiting stress level can be determined for a given flaw size, but experimental data must be relied upon to predict the flaw size, particularly the depth of the flaw. By proper design, the stresses can be maintained at sufficiently low levels to preclude rapid fracture in the outer races. The area of concern arises in engines of the future with increased rotor speeds which will generate high hoop stresses in the bearing inner races. Bearing materials with increased fracture toughness may be required for these applications.
3712 ENDOTHERAPY FOR CHRONIC PANCREATITIS IN CHILDHOOD.

Background. Chronic pancreatitis (CP) may be responsible for pain and vomiting in children. Endotherapy (ET) including ESWL of severe CP with ductal obstruction has shown to be effective and safe in adults. Few data are available for children. Aim. To review immediate and medium-term results of ET for severe CP in children. Patients and Method. 18 children who underwent therapeutic ERCP for symptomatic CP (Jan 91 - Apr 99) were divided in 2 groups according to their age: children (C) (n=8, males n=2, hereditary/idiopathic 4/4, mean age at onset of disease 3.1y, range 1.5- 5.7y, mean age at ET 5y, range 2.4-6.7y) and teenagers (T) (n=10, males n=6, hereditary/idiopathic 0/10, mean age at onset of disease 10y, range 6- 13, mean age at ET 12y, range 9-14). All patients were European, except 2 teenagers from India. ERCP was always performed under general anesthesia in the supine position. The following Olympus duodenoscopes were used: PJF 7.5 ( 4y). ERCP findings: normal bile ducts 18/18; dilated MPD 18/18, calcified calculi 5/18, MPD stricture 9/18, dominant dorsal duct 4/18. Results were considered: a) "excellent" when no further pain occurred, b) "good" when pain decreased in frequency and intensity but ET was repeated for relapsing symptoms, c) "fair" when immediate results were good but the patient eventually underwent further surgery. Results. The following procedures were performed in the two groups (C-T), respectively: biliary sphincterotomy 8/8-9/10, pancreatic sphincterotomy (PS) of major papilla 8/8-9/10, PS of minor papilla 4/8-1/10, ESWL 2/8-0/10, stones/plugs extraction 8/8-8/10, pancreatic stenting 3/8-1/10. Stents were exchanged in case of pain. ET was technically successful in all patients except one receiving a stent after failure of stones extraction. There were no complications, nor mortality. Follow-up averaged 5.9y (range 4.2-8.5y) in group C and results were "excellent" (n=3) or "good" (n=5). Follow-up averaged 3y (range 0.5-8y) in group T and results were "excellent" (n=8), "good" (n=1) or "fair" (n=1), this last girl undergoing further pancreatico-jejunostomy. Conclusions. ET of severe CP in children and teenagers is effective and safe, providing prolonged relief from symptoms. ET may significantly delay or even avoid surgery.
Bosniak Category IIF Designation and Surgery for Complex Renal Cysts

Purpose: We investigated whether adding the IIF categorization improved the accuracy of Bosniak renal cyst classification, as evidenced by a low rate of progression in IIF lesions and a high rate of malignancy in category III lesions.Materials and Methods: We retrospectively reviewed the records of patients with complex renal cysts categorized as a Bosniak IIF or III. Surveillance imaging and pathological outcomes of category IIF cysts were recorded to determine radiological predictors of progression. Pathological outcomes of category III cysts were recorded to determine the malignancy rate.Results: A total of 112 patients met study inclusion criteria, of whom 81 were initially diagnosed with a category IIF cyst and 31 had a Bosniak category III cyst. At a median followup of 15 months 14.8% of Bosniak IIF lesions progressed in complexity with a median time to progression of 11 months (maximum greater than 4 years). There were no differences in tumor or patient characteristics between cysts that progressed...
Nanocomposites: softer at the boundary.

A comparative study of silica-filled polystyrene and thin polystyrene films offers a new framework both for quantifying the typical shift in the glass-transition temperature of such systems, and prospects for the design of new nanocomposites.
Ultrastructure of the tentacles of Themiste lageniformis (Sipuncula)

An ultrastructural study of the tentacles of Themiste lageniformis (Sipuncula) was conducted as part of a larger study of head metamorphosis in the species.
Triadic frames for ambivalent experience

AbstractHuman semiotic constructions operate at the boundary of time where they serve both a representational function of showing the world as it is, and a presentational function of what could be in the next moment. Ambivalence is used to highlight the constant tension between what is and what could be, which is what drives meaning-making and thereby to point out that what we usually think of as having only two dimensions, e.g., (1) the world as it is now → (2) the world as it is at the ‘new’ now, is actually containing at least three aspects, e.g., (1) the world as it is now ← → (2) the “what could be” of the future → (3) and the world as it is at the ‘new’ now. Within this triadic frame, humans are constantly facing the ambiguity of their own meaning worlds, and the question becomes how to accept this ambiguity in our own meaning or avoid it to the degree that we can. In the face of our own ambiguity humans invoke higher-order semiotic regulators that rearrange the relation of different meaning complex...
Mixed lymphocyte reactions: absence of stimulation by irradiated allogeneic cells.

Abstract 137Cs-irradiated mouse spleen cells, in contrast to mitomycin-blocked cells, do not stimulate a mixed lymphocyte reaction (MLR) when cocultured with normal allogeneic lymphocytes. Attempts to find an irradiation dose which blocks the DNA-synthetic capability of alloantigenic cells, but which does not also render them unstimulatory in mixed cultures, have not been successful. Low-level irradiation (100–500 rad) does not completely block mitogen (PHA) reactivity, hence the target cells may be capable of participating in a two-way MLR. High-level irradiation (> 1000 rad), however, thoroughly blocks PHA-stimulated DNA synthesis and eliminates the capacity of these cells to stimulate an MLR. Potentiation of MLR by irradiated cells syngeneic with the reacting cell population was not possible in these experiments. Cell death and lysis in irradiated suspensions occurred during the 72-hr culture period. It is believed that a combination of cell lysis and irradiation-blocked metabolic events normally necessary for the MLR sufficies to explain the poor or nonexistent MLR's obtained in these experiments.
Spectroscopic, orbital, and physical properties of the binary Feige 24 and detection of transient He II absorption in the system

We have obtained new high-dispersion optical spectroscopy at Kitt Peak National Observatory (KPNO) and new International Ultraviolet Explorer (IUE) spectroscopy of the white dwarf+red dwarf binary system Feige 24. The optical range shows a composite DA+dM spectrum, together with H I Balmer and He I emission. The orbital phase dependence of the emission shows that it results from extreme ultraviolet (EUV) light reprocessing in the red dwarf upper atmosphere. The systems close enough and hot enough to show this reprocessing signature only recently emerged from common-envelope evolution. The ultraviolet spectrum exclusively emanates from the white dwarf and shows numerous heavy element absorption lines. We measured accurate radial velocities of the red dwarf component motion, traced by both optical absorption and emission lines, and new radial velocities of the white dwarf, traced by ultraviolet Fe V lines. Combining these measurements, we refined the orbital parameters presented by Vennes et al. (1991), and we confirmed that the white dwarf gravitational redshift is exceptionally small with 9 +/- 2 km/s. From this we deduced that the interior is either pure helium or carbon with a thick hydrogen layer, and we derived, for the combined interior compositions, a white dwarf mass and radius of M(sub WD) = 0.44-050 solar mass and R(sub WD) = 0.028-0.036 solar radius. We suggest that Feige 24 could be a typical case of close binary evolution leading to the formation of a low-mass helium white dwarf. The mass of the red dwarf and the inclination of the system naturally follow: M(sub dM) = 0.26-0.33 solar mass, i greater than or equal to 75 deg. High-dispersion H-alpha line profiles are asymmetrical, strongly enhanced toward the blue, suggesting a moving atmosphere possibly linked to a mass loss rate of 10(exp -10) solar mass/yr. The IUE spectra taken when the system is near inferior conjunction show strong He II 1640 A absorption. The profile is highly variable in width and intensity. Because it is correlated with the passage of the white dwarf at inferior conjunction, the absorption may occur in some foreground plasma emanated by the red dwarf and accumulating near a Lagrangian point or, alternatively, it may originate in an accretion spot on the white dwarf surface coaligned with the major orbital axis. Either way, the He II detection may imply substantial mass loss from the red dwarf with a corollary reclassification of Feige 24 as a mixed He/H DAO white dwarf resulting from accretion of secondary mass-loss material. Feige 24 is the prototype of a class of young, EUV-emitting, binary systems comprising a late main sequence secondary and a hot H-rich white dwarf; the class is characterized by optical and ultraviolet photospheric He II absorption, circumstellar C IV lambda (1550) absorption, and by the presence of EUV-induced, phase-dependent Balmer fluorescence. These young systems present the best opportunity to constrain theory of common-envelope evolution.
Surface-normal electroabsorption reflection modulators using asymmetric Fabry-Perot structures

The authors discuss a family of surface-normal electrooptic reflection modulators using asymmetric Fabry-Perot (ASFP) structures with GaAs-AlGaAs multiple quantum wells (MQWs) as the active medium. When an optimized top mirror reflectivity ( approximately 75%) is used, a voltage swing as low as 2 V is enough to change the device reflectivity by more than 40% with a contrast ratio of 50. A comparison with various Fabry-Perot structures shows that the ASFP is the best structure in terms of its operating voltage requirement and optical bandwidth. A sensitivity analysis shows that tolerances of 2 nm in operating wavelength, 0.5 V in operating voltage, 0.3% in layer thickness control or 10 degrees C in temperature variation can be expected from ASFPs with a finesse approximately 10. >
Dissociation dynamics of the HCl dimer ion

Abstract The dissociation pathways of (HCl)2+ are studied by a molecular beam-femtosecond multiphoton ionization technique, and via ab initio calculations at the MP2/6-31G(d,p) level and using Gaussian-2 theory. Results indicate, besides the commonly accepted proton-transferred HClH+Cl structure, a hydrogen-peroxide-like structure, (HCl–ClH)+, also exists and appears to be more stable. Their interconversion involves a barrier of 0.24 eV. A new dissociation product, Cl2+, is observed and shown to come from an intracluster reaction of the HCl dimer cation. Dissociations of the (HCl)2+ into H2Cl+ and HCl+ channels are preferred at low internal excitations, whereas dissociations into Cl2+ and HCl2+ require higher excitation energies.
Global ocean monitoring for the World Climate Research Programme.

Oceanic research and modelling for the World Climate Research Program will utilize several recently-developed instruments and measuring techniques as well as well-tested, long-used instruments. Ocean-scanning satellites will map the component of the ocean-surface topography related to ocean currents and mesoscale eddies and to fluctuating water volumes caused by ocean warming and cooling. Other satellite instruments will measure the direction and magnitude of wind stress on the sea surface, surface water temperatures, the distribution of chlorophyll and other photosynthetic pigments, the characteristics of internal waves, and possible precipitation over the ocean. Networks of acoustic transponders will obtain a three-dimensional picture of the distribution of temperature from the surface down to mid-depth and of long-term changes in temperature at depth. Ocean research vessels will determine the distribution and fate of geochemical tracers and will also make high-precision, deep hydrographic casts. Ships of opportunity, using expendable instruments, will measure temperature, salinity and currents in the upper water layers. Drifting and anchored buoys will also measure these properties as well as those of the air above the sea surface. Tide gauges installed on islands and exposed coastal locations will measure variations in monthly and shorter-period mean sea level. These tide gauges will provide ‘ground truth’ for the satellite maps of sea-surface topography, and will also determine variations in ocean currents and temperature.
Intrinsic fluorometric determination of the stable state of aggregation in hemoglobins.

Abstract Front-face fluorometry can detect steady-state intrinsic fluorescence of hemoglobins (R. E. Hirsch, R. S. Zukin, and R. L. Nagel, 1980 , Biochem. Biophys. Res. Commun., 93, 432–439), a property that can be used to study the dimerization of human hemoglobins (R. E. Hirsch, N. A. Squires, C. Discepola, and R. L. Nagel, 1983 , Biochem. Biophys. Res. Commun., 116, 712–718). We report that the stable dimeric hemoglobin components of the arcid clams Noetia ponderosa and Anadara ovalis exhibit fluorescence emission maxima shifted to longer wavelengths compared to tetrameric human hemoglobin. Conversely, the tetrameric major hemoglobin (Hb) component of A. ovalis exhibits an emission maximum similar to that of tetrameric Hb A. Hence, stable dimeric hemoglobins can be detected by emission maxima at longer wavelengths relative to Hb A. Fluorescence studies of ligand binding to these clam hemoglobins indicate structural and functional differences among these components and compared to Hb A. We conclude that different stable aggregation states of hemoglobins may be determined by intrinsic fluorescence when studied with front-face optics.
Photic after-discharge bursting during habituation of a leg flexion response.

Abstract Photically evoked after-discharge (PhAD) bursting was examined in lightly restrained albino rats during habituation and dishabituation of a leg flexion response. The initial effect of iterative footshock (200 trials, 0.17 mA, 2.5 msec duration, separated by 0.5 sec) was to significantly suppress PhAD occurrence. As foot stimulation progressed PhAD reappeared at reduced levels and more or less systematically returned to pretreatment control levels following cessation of foot stimulation. The dishabituation procedure significantly suppressed PhAD bursting. In addition, the suppressive effect of dishabituation stimulation appeared to carry over into response habituation. The results are interpreted as indicating that a gradual change in state occurs during response habituation, and further, a level of state exists which is optimal for PhAD elicitation. Possible neural mechanisms mediating PhAD suppression during response habituation are also discussed.
New paradigms in the repair of oxidative damage in human genome: mechanisms ensuring repair of mutagenic base lesions during replication and involvement of accessory proteins

Oxidized bases in the mammalian genome, which are invariably mutagenic due to their mispairing property, are continuously induced by endogenous reactive oxygen species and more abundantly after oxidative stress. Unlike bulky base adducts induced by UV and other environmental mutagens in the genome that block replicative DNA polymerases, oxidatively damaged bases such as 5-hydroxyuracil, produced by oxidative deamination of cytosine in the template strand, do not block replicative polymerases and thus need to be repaired prior to replication to prevent mutation. Following up our earlier studies, which showed that the Nei endonuclease VIII like 1 (NEIL1) DNA glycosylase, one of the five base excision repair (BER)-initiating enzymes in mammalian cells, has enhanced expression during the S-phase and higher affinity for replication fork-mimicking single-stranded (ss) DNA substrates, we recently provided direct experimental evidence for NEIL1’s role in replicating template strand repair. The key requirement for this event, which we named as the ‘cow-catcher’ mechanism of pre-replicative BER, is NEIL1’s non-productive binding (substrate binding without product formation) to the lesion base in ss DNA template to stall DNA synthesis, causing fork regression. Repair of the lesion in reannealed duplex is then carried out by NEIL1 in association with the DNA replication proteins. NEIL1 (and other BER-initiating enzymes) also interact with several accessory and non-canonical proteins including the heterogeneous nuclear ribonucleoprotein U and Y-box-binding protein 1 as well as high mobility group box 1 protein, whose precise roles in BER are still obscure. In this review, we have discussed the recent advances in our understanding of oxidative genome damage repair pathways with particular focus on the pre-replicative template strand repair and the role of scaffold factors like X-ray repairs cross-complementing protein 1 and poly (ADP-ribose) polymerase 1 and other accessory proteins guiding distinct BER sub-pathways.
Expected Profit, Price Change, and Risk Aversion

Perhaps no single area of recent inquiry has had greater impact on production economics than the duality results of Shepard, McFadden, and Uzawa. As Lau, Binswanger, and others have argued, these dual approaches (cost and profit functions) have substantial advantages over primal specifications (production functions plus equilibrium conditions). Although cost minimization is attractive for some problems, like measuring the elasticity of substitution, it seems sensible to view output as endogenous. Thus, one must "explain" output changesat least for proper estimation. This leads to profit maximization or some other explicit behavioral assumption. The profit function approach is used increasingly in agricultural economics (Lau and Yotopolous; Weaver; Yotopolous, Lau, Lin). Generally, this approach is applied without formal recognition of risk or risk-averse behavior. The purpose of this note is to illustrate the changes in expected profit given various models of risk. It shows that risk aversion biases the certainty results regarding factor demands and output supplies derived from the profit function. The qualitative and quantitative nature of these biases also are analyzed. These results should help researchers discern problems with the certainty approach and the possible consequences in agricultural applications where risk is present.
The Effect of Carotenols on Fertilizing Capacity of Fowl Sperm

Abstract THERE is little or no evidence to indicate that the carotenols have any biological value for the fowl. The exception most often cited is the work of Virgin and Klussman (1932). From their work, they concluded that the fowl is capable of converting the carotenols either into a provitamin or more likely into a vitamin affecting growth, which is different from carotene. The data, however, do not seem to substantiate the conclusions drawn. Kline, Schultze and Hart (1932); Schumacher, Scott, Hughes and Peterson (1944); and Weis and Bisbey (1947), on the other hand, found no vitamin A effect of xanthophylls on the growing of chicks. The work thus far on the effects of carotenols on the reproductive ability of the fowl is limited. Palmer and Kempster (1919) found that a carotenoid-free diet had no affect on the growth rate of chicks. When the birds matured both males and females showed . . .
Effect of wet snow on the null-reference ILS system

The null-reference instrument landing system (ILS) uses a horizontally polarized antenna on a tower to produce an elevation angle null which forms the VHF glide slope signal used in instrument approaches to a runway. Under certain combinations of snow and Earth wetness, there is a severe reduction in the amplitude of the ground reflected signal component. This can severely degrade the glide-slope null and thus the ILS system. >
The Socio–Cognitive Dynamics of Entrepreneurial Ideation:

How do entrepreneurs obtain the creative ideas they need to develop innovative new products? We interviewed 32 technology entrepreneurs to generate a grounded theory as to how technology entrepreneurs use social behaviors, techniques, and cognitive processes to generate, validate, and refine ideas for new products, processes, or services. The results reveal a complex, cyclical, and recursive multilevel social process emphasizing active and social experimentation. Greatest ideational productivity occurs when “trusted partners” exchange and refine ideas through a form of shared cognition. The findings will be useful to researchers and practitioners interested in entrepreneurship, social creativity, and management team dynamics.
Neighborhoods and trajectories in Kohonen maps

The Kohonen map is a basic paradigm of unsupervised learning. Quite a few descriptions exist of the possibility to expand other paradigms, and to describe their output behavior, for example, the functions that can be learned and the trajectories in the output space. The main parameters of Kohonen maps are the underlying topology and the metric used. In this paper the concepts of nearest neighbor, neighbor, neighborhood and underlying topology are formalized in a set-theoretic manner and thus expanded. Similarly, the concept of metric is enhanced by the introduction of similarity measures. A theorem on continuity of output is proved for such measures.
Some Factors Affecting the Biological Quality of Turkey Hatching Eggs

Abstract EGGS of the domestic chicken and, to a smaller extent, of other poultry species have been widely used in embryological investigations. The principal “operational” reasons for this are: (1) the availability of fertile eggs, (2) the oviparous type of development, making observation and manipulation of the embryo relatively easy, and (3) the ease of control over the macro-environment during incubation. Usually, a study involving gross morphological observations of avian embryos calls for the use of some standard for measuring the rate of development per unit of time, i.e. hours or days of incubation. To fill this need, staging series have been established to permit meaningful comparisons of the rate of embryonic development following a given period of incubation. Because of temporal as well as morphological differences that characterize the embryogenesis of different species of birds, these staging standards have had to be adapted for each particular species. Thus, the staging…
Disparities in herpes simplex virus type 2 infection between black and white men who have sex with men in Atlanta, GA

HIV disproportionately affects black men who have sex with men, and herpes simplex virus type 2 is known to increase acquisition of HIV. However, data on racial disparities in herpes simplex virus ...
Improvement in Hypercalcemia with Cinacalcet after Kidney Transplantation

Cinacalcet, a calcimimetic, was evaluated in persistent hyperparathyroidism after kidney transplantation (Tx). Ten kidney transplant recipients and one kidney-pancreas recipient with persistent post-Tx hypercalcemia (serum calcium [SCa] > 10.2 mg/dl), stable graft function, and intact parathyroid hormone (iPTH) > or = 2 times normal received 30 mg/d cinacalcet between 2 mo and 5 yr after Tx. SCa, serum phosphorus (SP), and iPTH were measured before and after cinacalcet. Mean pre-cinacalcet SCa was 10.9 mg/dl (8.6 to 11.9 mg/dl). Average pre-cinacalcet SP was 2.9 mg/dl (1.8 to 4.0 mg/dl). Mean pre-cinacalcet iPTH was 267.0 pg/ml (99 to 723 pg/ml). After cinacalcet, SCa decreased on average by 1.6 mg/dl (95% confidence interval 1.2 to 2.1; P < 0.0001). Post-cinacalcet SP increased on average 0.45 mg/dl (P = 0.046). Post-cinacalcet iPTH averaged 156.9 mg/dl (P = 0.10). Graft function remained stable. Cinacalcet lowers SCa and raises SP in the short term in patients with persistent post-Tx hyperparathyroidism; long-term bone effects and persistent hyperparathyroidism merit further study.
Collective Action by Physicians: Beyond Strikes

“Collective action” usually brings to mind images of picket signs held by laborers striking for better wages and benefits. Collective action, however, need not be limited to the withholding of labor. Nor need it involve only the working or middle classes, as airline pilots have recently demonstrated. Finally, collective action need not have as its only purpose the self-interest of the group. Collective action does, however, always involve a joining together of individuals united by common goals or interests in order to consolidate power for the purpose of negotiating with another group or entity. Examples of collective action obviously include striking, other withholding labor actions, and slowdowns, but can also include many other activities. “Paper strikes,” for example, have been threatened or used by house officer organizations in the past. In a paper strike, patient care continues but without documentation, and thus, the institution suffers from absent or delayed financial remuneration.
Quantitation of Cat Immunoglobulins in the Hemolymph of Cat Fleas (Siphonaptera: Pulicidae) After Feeding on Blood

Passage of ingested cat immunoglobulin G (IgG) into the hemocoel of cat fleas, Ctenocephalides felis (Bouche), was examined using antibody capture enzyme-linked immunosorbent assays (ELISA) and Western blotting. Fleas were fed heparinized cat blood via membrane feeders. Cat IgG was present in the hemolymph of engorged female fleas 1 h after ingestion at an estimated quantity of 35 ± 14 μg/ml. The prevalence of fleas with demonstrable cat IgG in their hemolymph 1 h after feeding was 100% for both female and male fleas. Following a single blood meal, cat IgG was present in the hemolymph of all 15 fleas tested 1 h after ingestion but dissipated below detectable levels in 10 of 20 fleas examined 3 h after ingestion, and was detectable in only 1 of 10 fleas examined 18 h after ingestion. However, when fleas were provided with continual access to blood over a 72-h period, IgG content in hemolymph, as measured in excised, triturated legs of individual fleas, remained fairly constant (3–16 pg IgG per sample). Flea feeding studies using specific antisera indicated that IgG in flea hemolymph retained its binding activity, and that at least a portion of the IgG was intact. Passage of ingested host antibody from gut into hemocoel is a prerequisite for the possible development of antiflea vaccines that target antigens outside of the flea midgut lumen (e.g., key components of the flea endocrine system controlling oogenesis).
String Stability Analysis of Selected Speed Control Laws for Interval Management

Interval Management (IM) is a future air traffic management concept that enables flight crews to achieve and maintain precise spacing intervals relative to other aircraft. Air traffic controllers (ATC) will initiate IM operations by identifying candidate aircraft pairs, where more precise spacing will help them to achieve air traffic initiatives; ATC will then provide an “IM aircraft” with a clearance to space relative to a “target aircraft” with a desired spacing interval. Previous IM-related research has evaluated the use of IM operations for spacing during the arrival and approach phase of flight. Some of that previous work has focused on the design of IM speed control laws that calculate speeds to achieve and maintain the desired spacing interval relative to the target aircraft. In arrival and approach uses of IM, a string of IM aircraft may be formed with each aircraft spacing relative to its immediately preceding aircraft. In order to ensure good string performance, the string stability of IM speed control laws must be studied and understood. This paper will examine string stability for three IM speed control laws that are candidate control laws for the IM avionics. Closed-form string stability results are developed for each speed control law, and simulation results are used to validate the closed-form results, as well as to reveal the effects of control saturation. Two scenarios are explored in simulation to evaluate and compare the string behavior for each speed control law.
Tutorial: Input uncertainty in outout analysis

Simulation output clearly depends on the form of the input distributions used to drive the model. Often these input distributions are fitted using finite samples of real-world data. The finiteness of the samples introduces errors in the input distributions, affecting the output. Yet this propagation of input model uncertainty to output uncertainty is rarely considered in simulation output analysis. This tutorial presents a discussion of input uncertainty issues and recently developed methodological approaches, set in the context of input uncertainty methods proposed over the past twenty years.
Laboratory measurements of the microwave opacity of sulfur dioxide and other cloud-related gases under simulated conditions for the middle atmosphere of Venus

Abstract Recent papers attributing the observed microwave opacity of the middle atmosphere of Venus to gaseous sulfur dioxide (SO2) and other cloud-related gases have motivated laboratory measurements of their microwave absorbing properties under simulated conditions for this region. In the pressure range from 1 to 5 atmospheres and in the temperature range from 297 to 355°K, the absorption of SO2 in a carbon dioxide (CO2) atmosphere, at 2.257 and 8.342 GHz, has been found to be approximately 50% larger than that calculated from Van Vleck-Weisskopf theory. The measured absorption is about 25 × 10 6 qƒ 2 p 1.20 T −3.1 ( dB km −1 ) , where q is the sulfur dioxide number mixing ratio, ƒ is frequency in gigahertz, p is pressure in atmospheres, and T is temperature in degrees Kelvin. This represents the best-fit expression to the observed pressure dependence, while theoretical values of frequency and temperature dependence are accepted as being consistent with the measurements. Another cloud-related gas, sulfur trioxide (SO3), was also tested in a CO2 atmosphere and found to be relatively transparent. These results reduce the amount of SO2 in the Venus middle atmosphere required to explain the opacity measured by radio occulatation, but this amount still exceeds the abundance measured in situ by atmospheric probes, suggesting that there must be another important source of opacity. Preliminary measurements of the 13-cm absorptivity of gaseous sulfuric acid (H2SO4) show it to be a strong microwave absorber, and thus likely to be responsible for a significant and possibly major part of the observed opacity.
Titelbild: Spectroscopic Tracking of Molecular Transport Junctions Generated by Using Click Chemistry (Angew. Chem. 28/2009)

Die In-situ-Erzeugung von Molekulbrucken uber Nanolucken, die durch “On-Wire”-Lithographie erzeugt wurden, gelingt mithilfe der Klickchemie. C. A. Mirkin et al. zeigen in der Zuschrift auf S. 5280 ff., dass diese molekularen Kontakte in hohen Ausbeuten entstehen, und schildern, wie das Verfahren fur eine Vielfalt von Molekularchitekturen verallgemeinert werden kann. Die molekulare Selbstorganisation in den Nanolucken lasst sich dank ihres starken elektromagnetischen Feldes verfolgen.
From handicap to disability: language use and cultural meaning in the United States.

The historical shift in discourse regarding disabled persons in the US is analysed by its core terms, handicap and disability. First, this shift in discourse is illustrated in the marketplace and i...
Large Scale Protein Profiling by Combination of Protein Fractionation and Multidimensional Protein Identification Technology (MudPIT)

In the past decade, shotgun proteomic analysis has been utilized extensively to answer complex biological questions. New challenges arise in large scale proteomic profiling when dealing with complex biological mixtures such as the mammalian cell lysate. In this study, we explored the approach of protein separation prior to the shotgun multidimensional protein identification technology (MudPIT) analysis. We fractionated the mammalian cancer cell lysate using the PF 2D ProteomeLab system and analyzed the distribution of molecular weight, isoelectric point, and cellular localization of the eluted proteins. As a result, we were able to reduce sample complexity by protein fractionation and increase the possibility of detecting proteins with lower abundance in the complex protein mixture.
Inferior Vena Cava Filter Penetration Resulting in Renal Pelvis Rupture With Urinoma Formation

Inferior vena cava (IVC) filter penetration is common and most often asymptomatic. However, penetration may potentially result in a variety of complications, including aortic trauma and small bowel perforation. Described is a case of IVC filter penetration resulting in renal pelvis perforation with urinoma formation.
Chromosome studies in the genus Alstroemeria. II. Chromosome constitutions of eleven additional cultivars.

Chromosomes of 11 cultivars of Alstroemeria were studied to determine their somatic constitutions. Two cultivars, ‘Eureka’ and ‘Zebra’, were diploid (2n = 2×= 16), six cultivars, ‘Yellow King’, ‘King Cardinal’, ‘Mona Lisa’, ‘Appelbloesem’, ‘Pink Triumph’ and ‘Rosita’ were triploid with 2n = 3×= 24, one cultivar, ‘Orange Beauty’ was a hypertriploid (2n = 3×+ 1 = 25), one cultivar, ‘Luciana’ was a hypotetraploid (2n = 4×– 1 =31) and one cultivar, ‘Jubilee’, was true tetraploid (2n = 4×= 32). This result suggests that polyploid cultivars may have more market value in this cut flower, Alstroemeria.
Impact of treating facilities' volume on survival for early-stage laryngeal cancer.

Background Treatment at a high-volume facility has been associated with better outcomes in a variety of conditions. The relationship between volume and survival from laryngeal cancer has not been examined previously. Methods A total of 11,446 early-stage laryngeal cancer patients (1996–1998) who reported to the National Cancer Database (NCDB) were analyzed. Proportional hazards regression was used to assess the relationship between survival and treatment volume controlling for other factors associated with survival. Results Treatment at low-volume facilities was associated with a significantly increased likelihood of death (hazard ratio 1.20, 95% CI 1.04–1.38). Surgical resection, as compared with radiation treatment, was associated with lower mortality (HR 0.74, 95% CI 0.69–0.80). Conclusion This study is the first to assess the relationship between survival and treatment volume in laryngeal cancer. Treatment at a high-volume facility is associated with better survival. Surgical treatment rather than radiation was also associated with better survival, although we could not control for confounders that may bias treatment selection. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Direct-coupled transistor-transistor logic: a new high-performance LSI gate family

The direct-coupled transistor-transistor logic (DCT/SUP 2/L) family consists of a multiple-emitter AND gate and a NOR gate similar to direct-coupled transistor logic (DCTL). High speed for low power is obtained by limiting the voltage swing and using a low voltage power supply of about 2 V. Using a conservative, standard Schottky process, the DCT/SUP 2/L NOR gate has a delay of about 1 ns for 4-mW gate power. A computer-aided analysis shows that this is faster than the basic gates of emitter function logic (EFL), emitter-coupled logic (ECL), or Schottky transistor-transistor logic (T/SUP 2/L) with the same process and gate power. A comparison of actual arithmetic logic units shows that Schottky DCT/SUP 2/L is smaller and faster than ECL and Schottky T/SUP 2/L. The higher speed and density of DCT/SUP 2/L makes it a better large-scale integration (LSI) concept than the other logic families.
Phylogenetic relationship and geographic distribution of multiple human T-cell lymphotropic virus type II subtypes.

The currentenv-based subtyping of human T-cell lymphotropic virus type II (HTLV-II) identifies only two heterogenetic groups, HTLV-IIa and HTLV-IIb. To better understand the genetic diversity and phylogeny of HTLV-II, we examined the most divergent genomic region of HTLV-II, the long terminal repeat, by using restriction fragment length polymorphism (RFLP) and sequence analysis. Long terminal repeat sequences were amplified from peripheral blood mononuclear cells by PCR and digested with seven restriction endonucleases that differentiated HTLV-II into five HTLV-IIa (IIa0 to IIa4) and six HTLV-IIb (IIb0 to IIb5) restrictiontypes,withHTLV-IIa0andHTLV-IIb0beingprototypesfortheMoTandNRAisolates,respectively. We examined 169 HTLV-II-infected samples, including 123 from blood donors and intravenous drug users (IDU) from the Americas, 16 from IDU from Europe, and 30 from Amerindians. Of the 169 samples, 109 (64.5%) were categorized as HTLV-IIa and 60 (35.5%) were categorized as HTLV-IIb. The predominant restriction types seen among the U.S. blood donors and U.S. IDU were IIa0 (68.7%) and IIb4 (10.4%). Four Spanish and seven Italian samples were IIb4, whilefive Norwegian samples were IIa2. Twelve Guaymi and all ten Seminole samples were single restriction types (IIb1 and IIb5, respectively), whereas the two Navajo and six Pueblo samples had a mixture of restriction types IIa0, IIa4, and IIb5. Of the HTLV-IIb restriction types observed in the U.S. non-Indians, 42.8% appear to have originated from the North Amerindian (IIb5), while 57.2% were similar to the European IIb4 restriction type. Sequences of 15 selected HTLV-II samples were determined and phylogenetically compared with 7 previously published HTLV-II LTR sequences. The derived topologies revealed three HTLV-IIa phylogroups (A-I to A-III) and four HTLV-IIb phylogroups (B-I to B-IV). Furthermore, the HTLV-IIa phylogroups appear to have evolved from the HTLV-IIb phylogroups. In the HTLV-IIa cluster, a Navajo (A-I) and a Brazilian (A-II) sequence formed separate phylogroups, while the remainingIIasequencesformedasinglephylogroup(A-III).ThefourHTLV-IIbphylogroupswererepresented predominantly by a New York IDU (B-I), European IDU (B-II), North Amerindian and NRA (B-III), and Central Guaymi Indian (B-IV) sequence(s). Comparison of the phylogenetic data with the RFLP results revealed that results of the two methods correlated completely, demonstrating the ability of the RFLP method to predict the phylogroup of HTLV-II-infected samples accurately and quickly.
Apical Ca2+-Activated K+-Channels in Mouse Parotid Acinar Cells

Ca2+ activation of Cl-- and K+-channels are key events underlying stimulated fluid secretion from parotid salivary glands. Cl--channels are exclusively present on the apical plasma membrane (PM) while the localization of K+-channels has not been established. Mathematical models have suggested that localization of some K+-channels to the apical PM is optimum for fluid secretion. A combination of whole cell electrophysiology and temporally resolved digital imaging with local manipulation of intracellular [Ca2+] was used to investigate if Ca2+-activated K+-channels are present in the apical PM of parotid acinar cells. Initial experiments established Ca2+ buffering conditions that produced brief, localized increases in [Ca2+] following focal laser photolysis of caged-Ca2+. Conditions were employed to isolate K+ and Cl- conductances. Photolysis at the apical PM resulted in a robust increase in K+ and Cl- currents. A localized reduction in [Ca2+] at the apical PM following photolysis of Diazo-2, a caged-Ca2+ chelator, resulted in a decrease in both K+ and Cl- currents. The K+ currents evoked by apical photolysis were partially blocked by both paxilline and TRAM-34, specific blockers of BK and IK respectively and almost abolished by incubation with both antagonists. Apical TRAM-34 sensitive K+ currents were also observed in BK null parotid acini. In contrast, when the [Ca2+] was increased at the basal PM no increase in either K+ or Cl- currents was evoked. These data provide strong evidence that K+- and Cl--channels are similarly distributed in the apical PM. Furthermore, both IK and BK channels are present in this domain and that the density of these channels appears higher in the apical vs. basal PM. In total, this study provides support for a model in which fluid secretion is optimized following expression of K+-channels specifically in the apical PM.
An Efficient Approach to Estimate Critical Value of Friction Coefficient in Brake Squeal Analysis

Automotive brake squeal generated during brake applications has become a major concern in automotive industry. Warranty costs for brake noise related complaints have been greatly increasing in recent years. Brake noise and vibration control are also important for the improvement of vehicle quietness and passenger comfort. In this work, the mode coupling instability mechanism is discussed and a method to estimate the critical value of friction coefficient identifying the onset of brake squeal is presented. This is achieved through a sequence of steps. In the first step, a modal expansion method is developed to calculate eigenvalue and eigenvector sensitivities. Different types of mode couplings and their relationships with possible onset of squeal are discussed. Then, a reduced-order characteristic equation method based on the elastically coupled system eigenvalues and their derivatives is presented to estimate the critical value of friction coefficient. The significance of this method is that the critical value of friction coefficient can be predicted accurately without the need for a full complex eigenvalue analysis, making it possible to determine the sensitivity of system stability with respect to design parameters directly.
Continental Sequence Stratigraphy of the Upper Triassic (Norian–Rhaetian) Chinle Strata, Northern New Mexico, U.S.A.: Allocyclic and Autocyclic Origins of Paleosol-Bearing Alluvial Successions

Abstract Two age-equivalent Upper Triassic fluvial successions deposited on the continental interior of the southwestern United States were evaluated using an adapted marine stacking-pattern analysis methodology. A three-tier cyclic hierarchy is present in the strata at both study areas. Meter-scale fining-upward fluival aggradation cycles (FACs) comprise fluvial aggradational cycle sets (FACSETs) 4–15 m thick (avg. 8.4 m). FACSETs in turn stack into four fluvial sequences 26–48 m thick (avg. 41 m). Within these sequences, transgressive-systems-tract equivalents (TE) are characterized by channel sands and associated minor overbank deposits and relatively immature paleosols (i.e., high rates of deposition), whereas highstand- to falling-stage-systems-tract equivalents (HFE) are dominated by overbank muds and relatively well-developed paleosols (i.e., lower rates of deposition). These two fluvial successions, which are 200 km apart, contain age-equivalent fluvial sequences that record similar histories of deposition and pedogenesis: Sequence 1 contains only an incomplete HFE; Sequence 2 includes both the TE and HFE; Sequence 3 is an HFE; and Sequence 4 contains only a TE. Fluvial sequences likely accumulated in response to pulses of source area uplift and/or basin subsidence, which resulted in changes in accommodation. Conversely, higher-frequency FACs and FACSETs that occur within sequences do not correlate between study areas and are likely the products of autocyclic processes, such as channel avulsion, floodplain aggradation, and channel migration. These results suggest that regionally significant tectonic episodes may be discernible in suspended-load fluvial deposits that accumulated over a broad area.