cssi/SciSciGPT-SciSciNet huggingface dataset:
The effect of impurity content on thermally activated deformation in NiAl single crystals

NiAl-base materials are attractive candidates for high temperature structural applications due to their low density, excellent oxidation resistance and high thermal conductivity. However, in single crystal and polycrystalline form, NiAl suffers from low tensile ductility and toughness. The mechanisms responsible for the limited ductility of NiAl single crystals are still in question. For this reason, thermally activated deformation in NiAl single crystals has been studied with the use of strain-rate change experiments. The preliminary results suggest that the intrinsic mobility of a , and to a lesser extent a dislocations, is limited below the DBTT in NiAl. To examine the influence of interstitial impurities and the possibility that strain-aging embrittlement is the mechanism responsible for the limited ductility of NiAl, further experiments on high purity NiAl crystals have been conducted for comparison to the results on commercial purity crystals.
Monotonicity of Optimal Performance Measures for Polling Systems

We consider scheduling a single server in a multiclass queue subject to setup times and setup costs. We examine the issue of whether or not reductions in the mean and variance of the setup time distributions can lead to degraded system performance. Provided that setups are reduced according to a stochastically smaller ordering, we show that if an optimal policy is used both for the original system and for the system with reduced setup times, then an improvement in performance is guaranteed. Even in cases for which a truly optimal policy is unknown, idling can be employed to avoid degradation of performance as setup times are cut. We extend this approach to show that system performance is monotonic with respect to service time distributions, switching costs, holding costs, and uniform reductions in the arrival rates. Extensions to sequencedependent setups and job feedback are noted.
Ryanodine Receptor Phosphorylation, Calcium/Calmodulin-dependent Protein Kinase II, and Life-threatening Ventricular Arrhythmias

Ryanodine receptor (RyR2) dysfunction, which may result from a variety of mechanisms, has been implicated in the pathogenesis of cardiac arrhythmias and heart failure. In this review, we discuss the important role of Ca 2+ /calmodulin-dependent protein kinase II (CaMKII) in the regulation of RyR2-mediated Ca 2+ release. In particular, we examine how pathological activation of CaMKII can lead to an increased risk of sudden arrhythmic death. Finally, we discuss how reduction of CaMKII-mediated RyR2 hyperactivity might reduce the risk of arrhythmias and may serve as a rationale for future pharmacotherapeutic approaches.
Existence and uniqueness of solutions to a class of singular diffusion problems

Existence, uniqueness, and non-uniqueness results are given for a class of singular diffusion problems with variable diffusion rates. Continuity arguments are used on related initial value problems to produce the existence results. Uniqueness criteria are established for different sets of hypotheses and non-uniqueness results are discussed when these hypotheses fail.
A Computational Study of the Performance and Robustness Properties of Retrospective Cost Adaptive Control

We present a computational study of a discrete-time adaptive control algorithm that is eective for multi-input, multi-output systems that are either minimum phase or nonminimum phase. The adaptive control algorithm requires limited model information, specically, the rst nonzero Markov parameter and the nonminimum-phase transmission zeros of the transfer function from the control signal to the performance measurement. Furthermore, the adaptive control algorithm is eective for stabilization, command following, and disturbance rejection. For command following and disturbance rejection, the algorithm does not require knowledge of the command or disturbance spectrum. We explore computationally the algorithm’s performance and robustness in the presence of errors in the required modeling information.
Developments in Titanium Powder Metallurgy

The high buy-to-fly ratio associated with many titanium components, combined with forging and machining difficulties, and recent availability problems, has led to a strong drive for near-net titanium shape fabrication. A very promising method of attaining this goal is powder metallurgy. Two major approaches are considered in this article: the “elemental” and “pre-alloyed” powder methods. Shape-making capability and mechanical properties of both technologies are presented. Consideration is given to the cost-effectiveness of the processes and mechanical performance compared to conventional fabrication methods. Design philosophies, modified to include the presence of foreign particles in the compacted article, are discussed. Emerging advances in the technology are presented and future developments forecast.
Effect of hyperglycemia on ischemic brain damage during hypothermic circulatory arrest in newborn dogs.

The effect of hyperglycemia on ischemic brain damage was investigated in a newborn dog model of hypothermic circulatory arrest. Newborn dogs were anesthetized with halothane, paralyzed, and artificially ventilated to maintain normoxia and acidbase balance. Animals were surface-cooled to 20°C, after which cardiac arrest was effected with i.v. KCl. Before surface cooling, one-half of the dogs (n = 12) received a bolus injection of 50% glucose to increase plasma glucose concentrations to approximately 33 mmol/L (600 mg/dL); control littermates (n = 12) received an equivalent volume of 1 N saline. The dogs remained asystolic for 1.75 h, after which cardiopulmonary resuscitation was accomplished. All animals survived, were allowed to recover from anesthesia at 37°C, and were maintained for 8 h of recovery, at which interval they underwent perfusion-fixation of their brains for pathologic analysis. Histologic grading of brain damage showed no statistically significant difference in the severity of neuronal necrosis within the cerebral cortex or caudate nucleus between hyperglycemic and normoglycemic littermates, with greater brain damage apparent in the amygdaloid nucleus of the hyperglycemic dogs (p < 0.02). Brainstem injury occurred more frequently in the hyperglycemic animals(p < 0.05). Correlation of coefficients analyses revealed a positive correlation between the severity of brain damage and plasma glucose concentration for both the caudate nucleus and amygdaloid nucleus but not for the cerebral cortex. The findings suggest that hyperglycemia superimposed upon hypothermic circulatory arrest in the newborn dog accentuates brain damage only in selected regions of the brain, especially the caudate and amygdaloid nuclei and brainstem, excluding the cerebral cortex.
An Improved Modification of a Regression-Toward-the-Mean Demonstration

Abstract Earlier simulations illustrating regression toward the mean have been improved so that they bear a closer resemblance to the actual phenomenon. In addition to the improved correspondence, the modified simulation permits a clear understanding of regression artifacts in two quasi-experimental designs, the extreme groups design and the matching-from-different-populations design. Highlighted in the simulation are: (1) the inverse relationship between measurement reliability (or between-measure correlations) and the magnitude of regression effects; (2) the stability of means and variances in the presence of regression effects; and (3) the time-reversed character of regression effects.
Microchemical techniques in solving industrial problems

Using the techniques described, we have determined such elements as zinc, phosphorus, sulfur, manganese, iron, gold, and tin at levels below 1μg in samples of 1 mg or less. Now that the electron probe microanalyzer is becoming available to the microchemist, it will be used more extensively for solving microanalytical problems.
Nuclear Spin-Lattice Relaxation Via Paramagnetic Centers Without Spin Diffusion

Experiments have been performed which study the relaxation of a nuclear spin system by paramagnetic impurities under conditions which inhibit spin diffusion. When spin diffusion is effectively absent, the magnetization is found ultimately to approach its equilibrium value as $\mathrm{exp}[\ensuremath{-}{(\frac{t}{{\ensuremath{\tau}}_{1}})}^{\frac{1}{2}}]$. An expression is obtained describing the relaxation of such a diffusionless spin system valid for all times and in agreement with experiment. Under suitable conditions higher order spin diffusion effects are also observed.
Effects of adenosine 5'-triphosphate and related agonists on cochlear function.

Abstract Several lines of evidence implicate a neurotransmitter/modulator role for ATP in the cochlea. Most of the work supporting such a notion has been accomplished using in vitro preparations of sensory hair cells or other cochlear tissues. Little is known regarding the functional consequences of ATP receptor activation in vivo. In the present experiments, we tested ATP and related agonist analogs for their effects on sound-evoked responses of the cochlea (cochlear microphonic, CM; summating potential, SP; distortion product otoacoustic emissions, DPOAE) and auditory nerve (compound action potential, CAP) in vivo and on outer hair cell (OHC) currents and cell length in vitro. In vivo, local application of these compounds was associated with conccntration-and intensity-dependent response alterations. The slowly-hydrolyzable P2y agonist, ATP-γ-S, was clearly of greatest in vivo potency: At low to moderate stimulus intensities, micromolar concentrations of this drug reduced all responses, in particular CAP and DPOAEs, which fell to the level of the noise floor. At high intensities, response suppression was smaller and SP was increased. In vivo effects of ATP, ATP-α-S and 2-Me-S-ATP were qualitatively similar to, but smaller in magnitude and requiring higher concentrations than those observed for ATP-γ-S. Adenosine was without significant effect on responses of the cochlea and auditory nerve. In vitro, effects of ATP-γ-S and ATP were similar: both induced inward currents in OHCs held at −60 mV without producing observable (> 0.3 μm) changes in OHC length. Results suggest that endogenous ATP influences cochlear function through receptors at several sites in the cochlea. Results suggest further that these response alterations arc mediated, at least in part, by receptors of the P2y subtype.
Forming the Pseudomonas Aeruginosa Translocon Requires Simultaneous Incorporation of PopB and PopD

Pseudomonas aeruginosa is a Gram-negative pathogen thatuses the Type III Secretion System to infect host cells. This system consists of a needle-like structure, by which proteins are secreted, and a translocon by which proteins are translocated across the plasma membrane of the target cell. The tip of the needle interacts with a hetero-oligomeric translocon formed by two proteins secreted through the needle: PopB and PopD. PopB and PopD can form pores individually or when mixed together. In model systems, mixed PopB and PopD assemble a unique hexadecameric complex containing 8:8 subunits of each protein. However, when not mixed, the translocators form mostly hexameric complexes in membranes. Does the formation of homo-oligomers interfere with the assembly of the hetero-oligomer?While studying the insertion of the putative PopD transmembrane segment into the membrane we noticed that the location of the segment differed in the presence and in the absence of PopB. Formation of a heterocomplex positioned the PopD segment into a more hydrophobic environment. We reasoned that this conformational change could be employed to determine if the conformation adopted by PopD in homo-oligomers is affected by the subsequent addition of PopB. If reversible, formation of hetero-oligomers will change the location of the transmembrane segment to a more hydrophobic environment.We found that the conformation adopted by PopD in homo-oligomers was not reverted by subsequent addition of PopB. These result is in good agreement with those showing that co-infection with two P. aeruginosa strains carrying only PopB and only PopD proteins are not able to translocate proteins into the target cells. Therefore, we conclude that an early interaction between PopB and PopD is required for the formation of a hetero-oligomeric translocon, and translocation of secreted effector proteins.
Viable but Nonculturable Bacteria Are Present in Mouse and Human Urine Specimens

The presence of viable but nonculturable bacteria in human clean-catch and mouse bladder-isolated urine specimens was investigated. Viable but nonculturable bacteria are alive but do not give rise to visible growth under nonselective growth conditions. Urine specimens obtained from human female volunteers with or without an active urinary tract infection were found to contain, on average, significantly more viable than culturable forms of bacteria. Additional support for the presence of viable but nonculturable cells in urine specimens considered sterile was obtained from examination of urine specimens obtained directly from the bladder of healthy mice. Because the viability assay used to study the viable but nonculturable condition is by necessity growth independent, and hence indirect, the accuracy of this assay that scores cells with intact cell membranes as being viable was studied. Greater than 95% of Escherichia coli cells exposed to lethal doses of UV irradiation were found to lose their membrane integrity within a day, a time frame similar to that used to examine urine specimens. These data suggest that viable but nonculturable cells can occur within regions of the urinary tract previously considered sterile.
Thermodynamics of transfer of sodium chloride from water to aqueous sucrose at 25°C

Enthalpies of transfer of sodium chloride over the mixed-solvent range from pure water to mole fraction sucroseX3=0.05 (50 wt. %) were determined calorimetrically at 25°C. These were combined with free energies of transfer at constant molality (per 100 g of mixed solvent) calculated from isopiestic activity coefficients to yield negative entropies of transfer. The positive free energy is approximately a linear function ofX3, and the negative enthalpies show that the free energies and activity coefficients of NaCl increase with temperature. The enthalpy behavior of NaCl in aqueous hydrogen peroxide and the urea is very similar to that in the present study, indicating the possibility of rough colligative effect for such systems.
The borane(III) complexes of (CH3)3PPCF3

Abstract Attachment of one or two BH 3 groups to the PCF 3 unit in the bicoordinate-P complex (CH 3 ) 3 PPCF 3 is achieved quantitatively in tetrahydrofuran at −40°. The P-P bond thus is stabilized: both (CH 3 ) 3 PPCF 3 BH 3 and (CH 3 ) 3 PPCF 3 (BH 3 ) 2 are nonvolatile white solids, stable in vacuo at 60°. Their NMR spectra support the argument that the unusual attachment of a second BH 3 group to the same electron-donor atom is due not to rehydridization but to the interaction of B-H bonding electrons with the P 3 d orbitals, relieving the P → B dative bond polarity. The spontaneous decomposition of (CH 3 ) 3 PPCF 3 BH 3 in THF at 25°, or the attack upon (CH 3 ) 3 PPCF 3 (BH 3 ) 2 by a gaseous stream of (CH 3 ) 3 P at 60°, produces much (CH 3 ) 3 PBH 3 but also an oil tentatively interpreted as (CH 3 ) 3 PPCF 3 -BH 2 PHCF 3 . Liquid ammonia also attacks (CH 3 ) 3 PPCF 3 (BH 3 ) 2 to make (CH 3 ) 3 PBH 3 and polymers; aniline attacks it somewhat similarly. Dry HCl apparently converts the BH 3 groups to BH 2 Cl, with little destruction of the P → B bonding.
High-temperature phases, crystal structures and the melting points for several of the transplutonium sesquioxides☆☆☆

The monoclinic form of Bk2O3 and the hexagonal forms of Bk2O3 and Cf2O3 have been prepared. The monoclinic structure of Bk2O3 was obtained in the range 1200–1700°C and was found to have lattice parameters of a0 = 14·197 ± 0·007 A, b0 = 3·606 ± 0·003 A, c0 = 8·846 ± 0·005 A and β = 100·23 ± 0·09°. At temperatures above 1750°C the monoclinic form of Bk2O3 transformed to a hexagonal structure having room-temperature lattice parameters of a0 = 3·754 ± 0·002 A and c0 = 5·958 ± 0·002 A. The hexagonal form of Cf2O3 was also prepared and the lattice parameters determined to be a0 = 3·72 ± 0·01 A and c0 = 5·96 ± 0·01 A. The m.p. of Cm2O3, Bk2O3 and Cf2O3 were measured and the values observed to be 2260, 1920 and 1750°C, respectively. A stability diagram for several of the actinide sesquioxides, which includes the above data, was constructed.
Larval Bivalve Shell Morphometry: A New Paleoclimatic Tool?

The shells of the pelagic larvae of bivalve mollusks may be useful as paleoclimatic indicators. An inverse relationship between temperature and maximum size of larval shells within a particular population is reported for a number of Recent species. Changes in the dimensions of the prodissoconch-dissoconch boundary on juvenile specimens may reflect changes in the ambient temperature of marine environments.
Investigation of a technique for calculating energy- independent effective interactions

Abstract The method of Suzuki and Lee for calculating an energy-independent effective interaction for use in shell-model calculations is investigated. Following a suggestion by Poppelier and Brussaard we apply the method to problems where one need not consider an inert core, calculating the binding energy of 2 H, 3 H and 4 He. We find that the extent to which the resulting interaction is energy independent depends sensitively on the accuracy to which the derivatives of the G - matrix with respect to the starting energy are calculated. An analytic expression for calculating these derivatives is presented. When this analytic expression is used the effective interaction is found to be energy independent.
The Clinical and Radiologic Features of Nodular Pulmonary Sarcoidosis

Study Objectives Nodular sarcoidosis is an uncommon presentation of sarcoidosis. Our objective was to describe the clinical characteristics of a large cohort of patients with nodular sarcoidosis. Methods We performed a retrospective study of patients with nodular sarcoidosis diagnosed at an urban teaching hospital over a 10-year period. Results Thirty-three patients with nodular sarcoidosis were identified. All patients were African-American. The mean age was 35 and the female-to-male ratio was 5:1. Twenty-six patients were current or former smokers. All patients had chest CT scan and/or chest radiograph evidence of pulmonary masses. Twenty-seven patients had multiple pulmonary masses/nodules and six had solitary pulmonary nodules/masses. The upper lobes were involved in 27 patients. Mediastinal lymphadenopathy and pleural-based masses were present in 30 and 20 patients, respectively. Extrapulmonary manifestations were present in 14 patients. All patients had tissue diagnosis of noncaseating granulomas with negative culture. Twenty-two patients underwent bronchoscopy with transbronchial biopsies, which were diagnostic in 19. Follow-up data were available on 27 patients: complete or nearly complete resolution of the pulmonary masses—either spontaneously or with systemic treatment—was documented for 19 patients, no change in the radiologic findings for 7 patients, and progression to pulmonary fibrosis for 1 patient. Conclusions Nodular sarcoidosis is a rare presentation of pulmonary sarcoidosis. It usually presents with multiple pulmonary masses that tend to be peripheral and are associated with mediastinal lymphadenopathy. Bronchoscopy with transbronchial biopsies has high diagnostic yield. Despite its ominous presentation, nodular sarcoidosis has favorable prognosis.
Characterization of surface deformation around vickers indents in monocrystalline materials

The deformation surrounding Vickers indents on copper and MoSi2 monocrystals has been characterized for two orientations of the indenter diagonals using optical, electron, and scanning probe microscopy. The surface topography around the indents was characterized using atomic force microscopy (AFM), whereas orientation imaging microscopy (OIM) was used to map the local crystallographic orientation of the surface surrounding one indent on copper and measure lattice rotations due to plastic strain. The results indicate that sink-in and pile-up behavior depend on in-plane crystallographic orientations rather than the orientation of the indenter. Regions with multiple slip show larger lattice rotations and sink-in, whereas regions with lower slip density have smaller lattice rotations and show pile-ups. Strains outside one indent were obtained from OIM data using kinematical relations for single-crystal plasticity. A von Mises strain of 29 pct next to the middle of indent edge on the surface of the sample was deduced from the analysis. This agrees well with the characteristic strain reported for Vickers indents.
Do intensive hospital antibiotic control programs prevent the spread of antibiotic resistance

The relation between antibiotic control and resistance was assessed by review of selected journal articles from 1988 through 1994. Most studies of control or monitoring do not report susceptibility pattern as an outcome measure. Several aspects of bias and confounding prevent more than analysis of temporal association between antibiotic use restriction and resistance pattern. However, in a few institutions there has been an increase in susceptibility to antimicrobials following intensive control or monitoring. Moreover, in a few hospitals, intensive antibiotic control for selected drug-organism pairs was associated with a high prevalence of susceptibility, and the proportion susceptible fell abruptly when control or monitoring was relaxed or removed. These examples, coupled with the recent emergence of new resistant organisms, justify attempts to determine the value of intensive antibiotic control as a preventive practice. Because these studies were performed in single institutions, their power to distinguish associations was poor. Cooperative multicenter studies are needed in which selection and classification biases are addressed prospectively, and in which confounding factors are controlled.
OPACIFYING EFFECT OF SOME FLUORIDES IN ENAMEL MILL ADDITIONS1

This paper describes the results of a study of the effect of barium fluoride and zinc fluoride on enamels when added in the mill. These fluorides were used with high silica, high borax, high lead oxide, and high antimony oxide enamels. The effect of these fluorides upon opacity and the creation of such defects as crawling and crazing are shown by triaxial diagrams and photographs.
Variability in Assessing Treatment Response: Metastatic Colorectal Cancer as a Paradigm

Purpose: The cutoff values currently used to categorize tumor response to therapy are neither biologically based nor tailored for measurement reproducibility with contemporary imaging modalities. Sources and magnitudes of discordance in response assessment in metastatic colorectal cancer (mCRC) are unknown. Experimental Design: A subset of patients9 CT images of chest, abdomen, and pelvis were randomly chosen from a multicenter clinical trial evaluating insulin-like growth factor receptor type 1–targeted therapy in mCRC. Using Response Evaluation Criteria in Solid Tumors (RECIST), three radiologists selected target lesions and measured “uni” (maximal diameter), “bi” (product of maximal diameter and maximal perpendicular diameter), and “vol” (volume) on baseline and 6-week posttherapy scans in the following ways: (i) each radiologist independently selected and measured target lesions and (ii) one radiologist9s target lesions were blindly remeasured by the others. Variability in relative change of tumor measurements was analyzed using linear mixed effects models. Results: Three radiologists independently selected 138, 101, and 146 metastatic target lesions in the liver, lungs, lymph nodes, and other organs (e.g., peritoneal cavity) in 29 patients. Of 198 target lesions total, 33% were selected by all three, 28% by two, and 39% by one radiologist. With independent selection, the variability in relative change of tumor measurements was 11% (uni), 19% (bi), and 22% (vol), respectively. When measuring the same lesions, the corresponding numbers were 8%, 14%, and 12%. Conclusions: The relatively low variability in change of mCRC measurements suggests that response criteria could be modified to allow more accurate and sensitive CT assessment of anticancer therapy efficacy. Clin Cancer Res; 20(13); 3560–8. ©2014 AACR .
Motivating Music Students: A Review of the Literature

John Dewey knew that when students were actively involved in their learning, they were more motivated and achieved higher. Unfortunately, our practices often negatively affect motivation, such as w...
Eigenvalue and eigenvector decomposition of the discrete Fourier transform

The principal results of this paper are listed as follows. 1) The eigenvalues of a suitably normalized version of the discrete Fourier transform (DFT) are {1, -1,j, -j} . 2) An eigenvector basis is constructed for the DFT. 3) The multiplicities of the eigenvalues are summarized for an N×N transform as follows.
Flower-petal mode converter for NLC

It is important to minimize power loss in the waveguide system connecting klystron, pulse-compressor, and accelerator in an X-Band NLC. However, existing designs of klystron output cavity circuits and accelerator input couplers utilize rectangular waveguide which has relatively high transmission loss. It is therefore necessary to convert to and from the low-loss mode in circular waveguide at each end of the system. A description is given of development work on high-power, high-vacuum 'flower-petal' transducers, which convert the TE/sub 10/ mode in rectangular guide to the TE/sub 01/ mode in circular guide. A three-port modification of the flower petal device, which can be used as either a power combiner at the klystron or a power divider at the accelerator is also described. >
DIRECTED EVOLUTION OF SUBTILISIN E IN BACILLUS SUBTILIS TO ENHANCE TOTAL ACTIVITY IN AQUEOUS DIMETHYLFORMAMIDE

Sequential rounds of error-prone PCR to introduce random mutations and screenrng of the resultant mutant libraries have been used to enhance the total catalytic activity of subtilisin E significantly in a non-natural environment, aqueous dimethylformamide (DMF). Seven DNA substitutions coding for three new amino acid substitutions were identified in a mutant isolated after two additional generations of directed evolution carried out on 10M subtilisin E, previously ‘evolved’ to increase its specific activity in DMF. A Bacillus subtilis-Escherichia coli shuttle vector was developed in order to increase the size of the mutant library that could be established in B.subtilis and the stringency of the screening process was increased to reflect total as well as specific activity. This directed evolution approach has been extremely effective for improving enzyme activity in a non-natural environment: the resulting-evolved 13M subtilisin exhibits specific catalytic efficiency towards the hydrolysis of a peptide substrate succlnyl-Ala-Ala-Pro-Phe-p-nitroanilide in 60% DMF solution that is three times that of the parent 10M and 471 times that of wild type subtilisin E. The total activity of the 13M culture supernatant is enhanced 16-fold over that of the parent 10M.
JOINT SEALANT AND STRUCTURAL PERFORMANCE AT THE OHIO ROUTE 50 TEST PAVEMENT

The performance of joint sealants and the structural condition of the pavement at the Ohio Route 50 test site after 3 years in service are reported. The project involved 10 different sealant compounds (4 silicone, 2 hot-applied, and 4 compression seals) and 4 unsealed sections. A total of 15 different sealant-joint configuration combinations are examined. Compression seals generally outperformed the other sealants, and sealants in the westbound lanes were more effective than those in the east-bound lanes. These observations suggest that crew experience in sealant installation is a critical factor. Nonetheless, structural performance and surface profile smoothness appeared to be unrelated to sealant condition. Many of the sealant sections with high effectiveness values also exhibited high percentages of structural distresses and decreases in pavement surface smoothness. Flooding after intense rainfall may have softened the subgrade and caused transverse cracking and corner breaks. Implementing a drainage o...
Depth perception in the rat (Rattus Norvegicus): prepotency of three-dimensional over two-dimensional surfaces.

The descent behavior to two- and three-dimensional surfaces in a depth situation was measured and compared for 45–50-days-old hooded rats. When depth differences between surfaces were controlled, significantly more descents were made to three-dimensional than to the two-dimensional surface. The results suggest that a three-dimensional surface—more representative of an animal's natural terrain—provides a more informative environment for motion parallax than does a two-dimensional one.
Messung des umlaufenden Kältestoffes

Eine wertvolle Kontrolle der Warmemessungen gibt die Bestimmung der umlaufenden Menge des Kaltetragers durch den unmittelbaren Versuch. Hierzu eignet sich am besten die Erzeugung eines Druckunterschiedes in der Flussigkeitsleitung durch eine Blende mit scharfen Kanten oder durch eine Duse mit guter Abrundung. Man mist diesen Druckunterschied mit einem Differentialmanometer; fur genaue Beobachtungen dient hierzu das U-formig gekrummte Rohr mit Quecksilberinhalt.
Effective interim collaboration: how firms minimize transaction costs and maximise transaction value

This study of automotive transaction relationships in the U.S.A. and Japan offers abta which indicate that transaction costs do not necessarily increase with an increase in reiation-specijk investments. We empirically examine the conditions under which transactors can simultaneously achieve the twin benejits of high asset specificity and low transaction costs. This is possible because the dtfferent safeguards which can be employed to control opportunism have different set-up costs and result in different transaction costs over dl~erent time horizons. We examine in detail the ~ractices of Javanese firms which result in effective inteq%n collaboration. @ .. 1997 by John- Wiley & Sons: Ltd. "
Controls On Lower-Coastal-Plain Valley Morphology and Fill Architecture

Abstract Small rivers that form at the apex of the coastal prism are common along many passive margins. They typically have drainage basins < 1000 km2, and their headwaters are isolated to low-relief areas of the previous highstand shoreline. As sea-level fall exposes the apex of the coastal prism, incision and drainage-basin evolution of those small rivers should be strongly influenced by coastal paleotopography, but previous work suggests that paleodischarge is the dominant control on incised-valley dimension. To examine the controls on the morphologic evolution of small incised valleys, we examined 20 incised valleys in North Carolina situated close to the last interglacial shoreline, including coastal-prism-incised valleys, which have well-developed dendritic drainage networks on the highstand-shoreline topography, and tributary incised valleys, which form adjacent to and merge with larger piedmont incised valleys. Coastal prism (n = 18) and tributary (n = 2) incised-valley width, measured at the common bayhead-delta location, is proportional to drainage-basin area (long-term discharge); however, that comparison location overlaps with the knickzone only for the larger river systems. The knickzone of small river systems is located down dip from the modern bay-head delta, which is likely due to slower rates of knickpoint migration. We use geophysical and lithologic data from three incised valleys to highlight differences in regional valley morphology that can be used to distinguish between coastal-prism and tributary incised valleys. The Newport and North coastal-prism incised valleys connect to small Sangamonian drainage networks of 210 km2 and 50 km2, respectively. Those valleys widen and deepen at the knickzone, which is also where smaller tributary systems merge with the main trunk valley. The Scuppernong tributary incised valley has a drainage basin of 400 km2 and can be differentiated from other incised valleys based on the absence of a compound fill and continuous seaward deepening and widening from the upstream limit of the knickzone. The knickzone is the junction of the Scuppernong with the adjacent larger Roanoke incised valley, the depth of which controls base level for the Scuppernong. The dramatic Scuppernong valley widening, in a down-dip direction, is principally due to highly erosive bay-ravinement processes associated with the adjacent much larger drowned Roanoke incised valley. These varying modes of valley evolution, specifically controls of paleotopography on valley incision and ravinement, explain the morphologies of small drowned river-mouth estuaries and improve understanding of basin-scale sediment-transport pathways.
Plasma Renin Activity by LC-MS/MS: Development of a Prototypical Clinical Assay Reveals a Subpopulation of Human Plasma Samples with Substantial Peptidase Activity

BACKGROUND: For management and treatment of secondary hypertension, plasma renin activity (PRA) assay is considered an essential diagnostic tool. We developed a liquid chromatography–tandem mass spectrometry (LC-MS/MS)-based approach to PRA offering improvements in laboratory workflow and throughput. During development, we observed a substantial number of clinical samples that have strong degradation activity toward angiotensin (Ang) I during generation. A preliminary characterization of this degradation activity was performed, and we provide here a method by which this degradation can be monitored via the addition of an isotope-labeled degradation standard. METHODS: Automated online sample extraction coupled with HPLC was used to isolate Ang I and internal standard from plasma. The effluent from the analytical column was directed to a triple quadrupole MS operated in selected reaction monitoring mode, monitoring the a5 and b5 product ions from the [M+3H]+3 precursors. Routine analysis could be achieved with as little as 150 μL plasma. RESULTS: We identified both C-terminal and N-terminal degradation products of Ang I using isotope-labeled peptides as controls and substrates. In 2%–5% of patient samples, the degradation essentially eliminated any Ang I produced during generation. CONCLUSIONS: Our method requires reduced sample handling when compared with an RIA and eliminates the need for extended generation times for samples with low renin activity. Degradation of Ang I during generation appears to be a confounding variable in the interpretation of results from some clinical samples. Samples with profound degradation activity can be identified using a degradation standard that is added at the start of generation.
Rocker cell culture incubator

A rocker mammalian cell culture system is described. The basic mechanical component is a special incubator with contained rocker culture trays. The system provides for precise environmental temperature regulation with intermittent rocking of contained cultures in such a manner as to permit thin fluid overlay of cells with maximum accessibility to oxygen while circumventing the problems of evaporation, substrate depiction, etc.
Respiratory muscle responses elicited by dorsal periaqueductal gray stimulation in rats.

The periaqueductal gray matter is an essential neural substrate for central integration of defense behavior and accompanied autonomic responses. The dorsal half of the periaqueductal gray matter (d...
Phases of Ca from first principles

Structures and properties of many of the phases of Ca under pressure are calculated from first principles by a systematic procedure that minimizes total energy E with respect to structure under the constraint of constant volume V. The minima of E are followed on successive sweeps of lattice parameters for 11 of 14 Bravais symmetries for one-atom-per-cell structures. The structures include the four orthorhombic phases. Also included are the hexagonal close-packed and cubic diamond phases with two atoms per primitive cell. No uniquely orthorhombic phases are found; all one-atom orthorhombic phases over a mega-bar pressure range are identical to higher-symmetry phases. The simple cubic phase is shown to be stable where it is the ground state. The number of distinct one-atom phases reduces to five plus the two two-atom phases. For each of these phases the Gibbs free energy at pressure p, G(p), is calculated for a non-vibrating lattice; the functions G(p) give the ground state at each p, the relative stabilities of all phases and the thermodynamic phase transition pressures for all phase transitions over a several-megabar range.
CPT , T , and Lorentz violation in neutral-meson oscillations

Tests of $\mathrm{CPT}$ and Lorentz symmetry using neutral-meson oscillations are studied within a formalism that allows for indirect $\mathrm{CPT}$ and T violation of arbitrary size and is independent of phase conventions. The analysis is particularly appropriate for studies of $\mathrm{CPT}$ and T violation in oscillations of the heavy neutral mesons D, ${B}_{d},$ and ${B}_{s}.$ The general Lorentz- and CPT-breaking standard-model extension is used to derive an expression for the parameter for $\mathrm{CPT}$ violation. It varies in a prescribed way with the magnitude and orientation of the meson momentum and consequently also with sidereal time. Decay probabilities are presented for both uncorrelated and correlated mesons, and some implications for experiments are discussed.
On design of scheduling algorithms for advance bandwidth reservation in dedicated networks

There are an increasing number of high- performance networks that provision dedicated channels through circuit-switching or MPLS/GMPLS techniques to support large- scale data transfer. The available bandwidths on these dedicated links vary over time and therefore efficient bandwidth scheduling algorithms are needed to improve the utilization of network resources and satisfy diverse user requirements. Based on different path and bandwidth constraints, we formulate four instant scheduling problems for a data transfer request: (i) variable path with variable bandwidth (VPVB), (ii) fixed path with variable bandwidth (FPVB), (iii) variable path with fixed bandwidth (VPFB), and (iv) fixed path with fixed bandwidth (FPFB), with the common objective to minimize transfer end time for a given data size. We design an optimal algorithm for each of these scheduling problems with polynomial- or pseudo- polynomial-time complexity with respect to the network size and total number of time slots in a bandwidth reservation table.
Reporting Frequency, Information Precision and Private Information Acquisition

__Abstract__ This study examines whether the choice between quarterly and semiannual reporting affects the precision of investors' information and their private information acquisition activities. In the first part of this study, we show that a firm's reporting frequency has no effect on the average precision of investors' information. However, our analysis of announcement-period price variance and share turnover shows that an increase in reporting frequency does make interim and annual financial reports a more important component of investors' information set, relative to other sources of information. In particular, the results of this analysis suggest that investors of semiannual reporters hold more precise pre-announcement information than investors of quarterly reporters. In the second part of our study, we test one explanation for this finding. We argue that an increase in a firm's reporting frequency reduces investors' incentives to acquire private information between consecutive announcement dates and, consequently, should reduce information asymmetry among investors, increase share liquidity, and stimulate trading. Consistent with this reasoning, we find that quarterly reporters have lower average bid-ask spreads and higher abnormal share turnover than semiannual reporters.
Estimation of changes in instantaneous aortic blood flow by the analysis of arterial blood pressure

The purpose of this study was to introduce and validate a new algorithm to estimate instantaneous aortic blood flow (ABF) by mathematical analysis of arterial blood pressure (ABP) waveforms. The al...
Wildlife Reservoirs of Bovine Tuberculosis Worldwide: Hosts, Pathology, Surveillance, and Control:

Bovine tuberculosis due to Mycobacterium bovis is a zoonotic disease classically carried by cattle and spilling over into humans primarily by the ingestion of milk. However, in recent decades, there have been many endemic geographic localities whereM. bovis has been detected infecting wildlife reservoirs, limiting the progress toward eradication of this disease from cattle. These include cervids in North America, badgers in Great Britain, feral pigs in Europe, brushtailed possums in New Zealand, and buffalo in South Africa. An overview of these wildlife hosts will provide insight into how these reservoirs maintain and spread the disease. In addition, the authors summarize the pathology, current ongoing methods for surveillance, and control. In many instances, it has proven to be more difficult to control or eradicate bovine tuberculosis in wild free-ranging species than in domesticated cattle. Furthermore, human influences have often contributed to the introduction and/or maintenance of the disease in wildlife species. Finally, some emerging themes regarding bovine tuberculosis establishment in wildlife hosts, as well as conclusions regarding management practices to assist in bovine tuberculosis control and eradication in wildlife, are offered.
Dynein from serotonin-activated cilia and flagella: extraction characteristics and distinct sites for cAMP-dependent protein phosphorylation.

Serotonin, an activator of adenylate cyclase, stimulates motility in molluscan gill cilia and sperm flagella. To determine and compare potential targets of cAMP action, dynein was prepared from the lateral gill.cilia and sperm flagella of the mussel Mytilus edulis and the clam Spisula solidissima. In the flagella of both species, high-salt extraction removes about half of the ATPase activity, half of the alpha and beta heavy chains, and the outer arms. The dynein from both species sediments at 18-20 S, contains two or three intermediate chains, and three light chains. High-salt plus detergent removes most of the remaining dynein ATPase, alpha and beta heavy chains, and inner arms, also yielding a stable 18-20 S particle. In gill cilia of both species, high-salt extraction removes only 12-18% of the ATPase, up to 1/3 of the alpha heavy chains, an equivalent amount of beta heavy chain, and a subset of the outer arms. The dynein sediments at 18-20 S and, in Spisula, the heavy, intermediate, and light chains precisely co-sediment. High-salt plus detergent removes another 1/3 of the alpha heavy chains, an equivalent amount of beta heavy chain, and the remaining outer arms. The ATPase sediments mainly as a 13-14 S form showing considerable dissociation of co-sedimenting intermediate and light chains. The inner arms and at least half of the ciliary dynein ATPase activity remain unextractable, corresponding in mass mainly to an apparent beta heavy chain that is vanadate-cleavable. Cyclic AMP-dependent, calcium-independent phosphorylation takes place on specific dynein light chains in cilia but on only the dynein alpha heavy chain in flagella. Pre-activation of the flagella prevents subsequent addition of labeled phosphate. Phosphorylation has no effect on the steady-state ATPase properties. The single phosphate added to the flagellar alpha chain is located within the LUV1 vanadate photocleavage fragment. Considering the probable locus of the light chains and the site of the alpha heavy chain phosphorylation, both beyond the active site and toward the base of the molecule, these distinct phosphorylations may regulate dynein action by modulating arm flexibility or interaction.
Bowing Convective Systems in a Popular Operational Model: Are They for Real?

Abstract Bowing, propagating precipitation features that sometimes appear in NCEP's North American Mesoscale model (NAM; formerly called the Eta Model) forecasts are examined. These features are shown to be associated with an unusual convective heating profile generated by the Betts–Miller–Janjic convective parameterization in certain environments. A key component of this profile is a deep layer of cooling in the lower to middle troposphere. This strong cooling tendency induces circulations that favor expansion of parameterized convective activity into nearby grid columns, which can lead to growing, self-perpetuating mesoscale systems under certain conditions. The propagation characteristics of these systems are examined and three contributing mechanisms of propagation are identified. These include a mesoscale downdraft induced by the deep lower-to-middle tropospheric cooling, a convectively induced buoyancy bore, and a boundary layer cold pool that is indirectly produced by the convective scheme in this ...
Asymptomatic Occlusion of an Internal Carotid Artery in a Hospital Population: Determined by Directional Doppler Ophthalmosonometry

Reversal of blood flow in an ophthalmic artery as determined by directional Doppler ultrasound (OSM) was present in nine (3%) of 310 patients over 50 years of age who did not have complaints, diagnoses or examination findings suggesting disease of the central nervous system, and was present in nine (12%) of 73 patients with neurological disease selected as technical controls. Twenty-two of the control patients had four-vessel angiography. Five with OSM evidence of reversal of flow had functional occlusion of the appropriate internal carotid artery, and 17 without reversal did not. This study presents evidence that occlusion of an internal carotid artery frequently occurs without producing recognizable clinical dysfunction.
Novel CeO2-CuO-decorated enzymatic lactate biosensors operating in low oxygen environments.

Abstract The detection of the lactate level in blood plays a key role in diagnosis of some pathological conditions including cardiogenic or endotoxic shocks, respiratory failure, liver disease, systemic disorders, renal failure, and tissue hypoxia. Here, we described for the first time the use of a novel mixed metal oxide solution system to address the oxygen dependence challenge of first generation amperometric lactate biosensors. The biosensors were constructed using ceria-copper oxide (CeO2–CuO) mixed metal oxide nanoparticles for lactate oxidase immobilization and as electrode material. The oxygen storage capacity (OSC, 492 μmol-O2/g) of these metal oxides has the potential to reduce the oxygen dependency, and thus eliminate false results originated from the fluctuations in the oxygen concentration. In an effort to compare the performance of our novel sensor design, ceria nanoparticle decorated lactate sensors were also constructed. The enzymatic activity of the sensors were tested in oxygen-rich and oxygen-lean solutions. Our results showed that the OSC of the electrode material has a big influence on the activity of the biosensors in oxygen-lean environments. While the CeO2 containing biosensor showed an almost 21% decrease in the sensitivity in a O2-depleted solution, the CeO2–CuO containing electrode, with a higher OSC value, experienced no drop in sensitivity when moving from oxygen-rich to oxygen-lean conditions. The CeO2–CuO decorated sensor showed a high sensitivity (89.3 ± 4 μA mM−1 cm−2), a wide linear range up to 0.6 mM, and a low limit of detection of 3.3 μM. The analytical response of the CeO2–CuO decorated sensors was studied by detecting lactate in human serum with good selectivity and reliability. The results revealed that CeO2–CuO containing sensors are promising candidates for continuous lactate detection.
Fuel economy opportunities with an uncooled Dl diesel engine

Possibilites de realiser des economies de carburant avec un moteur diesel a injection directe non refroidi