cssi/SciSciGPT-SciSciNet huggingface dataset:
Spin-torque switching: Fokker-Planck rate calculation

We describe a general Fokker-Planck approach to understanding and calculating magnetization switching rates and noise in the recently observed phenomenon of spin-torque switching. In this phenomenon, which has possible applications to information storage, a large current passing from a pinned ferromagnetic (FM) layer to a free FM layer switches the free layer. Beginning with Brown [Phys. Rev. 130, 1677 (1963)], switching rates in magnetic systems have been calculated using the Fokker-Planck equation. In the small-oscillation limit, the equations have been solved analytically, giving a first-principles justification for phenomenological effective temperature theories: the spin-torque effect increases the Arrhenius factor $\mathrm{exp}(\ensuremath{-}E∕kT)$ in the switching rate by raising the effective spin temperature $T$. In the present Rapid Communication we generalize the nonlinear Fokker-Planck equation to the case of a Slonczewski spin torque. As an example, we use a linear approximation to calculate telegraph noise rates, leading to good qualitative agreement with recent experiments. However, our nonlinear formulation is also valid for large precessional oscillations. The method also allows the calculation of current-induced magnetic noise in current perpendicular to plane spin valve read heads.
Hybrid Semiconductor Core-Shell Nanowires with Tunable Plasmonic Nanoantennas

The microstructure of heterogeneous nanowires plays a major role in determining their properties. For example, core-shell nanowires composed of optically active p- and n-type semiconductors have photovoltaic properties that are superior to their planar counterparts due to more efficient charge separation owing to the high interfacial surface area and relatively small distance required to separate electron-hole pairs. The limited combined use of polymer, core-shell, and plasmonic compositions in nanostructured materials highlights the lack of versatility in current synthetic techniques and emphasizes the need for new synthetic techniques to address unmet challenges facing the photovoltaic community. Here, we report the electrochemical synthesis of solution dispersible, multi-segmented nanowires in which metallic nanostructures are precisely interfaced with core-shell polymeric and inorganic semiconductor materials with nanometer scale resolution.
Genetic deficiency of the alpha subunit of the guanine nucleotide-binding protein Gs as the molecular basis for Albright hereditary osteodystrophy

Abstract Patients who have pseudohypoparathyroidism type I associated with Albright hereditary osteodystrophy commonly have a genetic deficiency of the alpha subunit of the G protein that stimulates adenylyl cyclase (alpha Gs) (ATP pyrophosphate-lyase, EC 4.6.1.1). To discover the molecular mechanism that causes alpha Gs deficiency in these patients, we examined eight kindreds with one or more members affected with Albright hereditary osteodystrophy or pseudohypoparathyroidism and alpha Gs deficiency. In these families, alpha Gs deficiency and the Albright hereditary osteodystrophy phenotype were transmitted together in a dominant inheritance pattern. Using a cDNA hybridization probe for alpha Gs, restriction analysis with several endonucleases showed no abnormalities of restriction fragments or gene dosage. RNA blot and dot blot analysis of total RNA from cultured fibroblasts obtained from the patients revealed approximately equal to 50% reduced mRNA levels for alpha Gs in affected members of six of the pedigrees but normal levels in affected members of the two other pedigrees, compared to mRNA levels in fibroblasts from unaffected individuals. By contrast, mRNA levels encoding the alpha subunit of the G protein that inhibits adenylyl cyclase were not altered. Our findings suggest that several molecular mechanisms produce alpha Gs deficiency in patients with pseudohypoparathyroidism type Ia and that major gene rearrangements or deletions are not a common cause for alpha Gs deficiency in pseudohypoparathyroidism type I.
Convergence of the axial walls of full veneer crown preparations in a dental school environment

Abstract This research report used a simple and accurate method of measuring the convergence of full veneer crown preparations. A random sample of 909 dies was selected from all dies of full veneer crown preparations done at the University of Colorado, School of Dentistry student clinic over a 6-year period. All preparations were accomplished by third- and fourth-year dental students under either normal clinic conditions or under special (proficiency) testing conditions. The mean convergence angles were 19 degrees (S.D. ± 9.8 degrees) for nonexamination conditions and 15.7 degrees (S.D. ± 5.5 degrees) for examination procedures. These angles are far in excess of those normally recommended in the fixed prosthodontic textbooks. The values obtained in this investigation agree with the findings of most of the current published studies on the subject.
Spatial resolution and noise in organic light-emitting diode displays for medical imaging applications

We report on the resolution and noise characteristics of handheld and workstation organic light-emitting diode (OLED) displays in comparison with liquid crystal displays (LCDs). The results demonstrate advantages, in terms of sharpness, of handheld OLED displays with modulation transfer function (MTF) values exceeding 0.60 at the Nyquist frequencies. The OLED workstation included in this study exhibits significant signal contamination among adjacent pixels resulting in degraded resolution performance indicated by horizontal and vertical MTF values of 0.13 and 0.24 at the Nyquist frequency. On the other hand, its noise characteristics are superior to the LCD workstation tested. While the noise power spectral (NPS) values of the OLED workstation are 8.0×10−6 mm2 at 1 mm−1, the LCD workstation has NPS values of 2.6×10−5 mm2. Although phone-size OLED displays have superior resolution and noise per pixel, the perceived resolution characteristics at appropriate viewing distances are inferior to tablet-size and workstation LCDs. In addition, our results show some degree of dependency of the resolution and noise on luminance level and viewing orientation. We also found a slightly degraded resolution and increased low-frequency noise at off-normal orientations in the handheld displays.
Crank-Slider With Spring Constant Force Mechanism

This paper explores the development and performance of new constant-force compliant mechanisms that involve the addition of a translational spring element to slider-crank constant force mechanisms. The translational spring element has the additional requirement that, similar to a slider, it resists off-axis loads sufficiently to permit translation along only one axis. Geometric and energy storage parameters have been determined by optimization for five classes of mechanisms. The results of the optimization are values for geometric and energy storage parameters for each mechanism class for various levels of the translational spring parameter and various levels of constant-force behavior. The new configurations experience decreasing performance with increasing translational spring stiffness. The potential to implement a translational spring that also acts as a slider link provides the motivation for the new configurations. Such a spring would have the potential to completely remove friction from the mechanism and provide a constant-force solution that could replace current solutions such as hydraulic or pneumatic devices. The new configurations also have the potential to be manufactured as one piece or in layers, opening up new arenas for compressive constant-force mechanisms. Prototyping and testing of one of the new configurations are included as an example to demonstrate the use of the behavioral model.Copyright © 2004 by ASME
An In-house Program of Continuing Education for Perinatal Nurses

A learning program implemented with motivation and peer-group teaching was combined with a program of learning through research on a topic and sharing this information with others. In using these two methods of learning, both inexperienced and highly skilled perinatal nurses have been able to continue effectively their education, using resources in their own institution.
Integration of the SV40 promoter/enhancer sequences in an anchorage-independent clonal subline of SV40-infected human keratinocytes

Long-term cultures of SV40-infected human keratinocytes contain integrated, but structurally altered copies of the viral sequences. The presence of these sequences is required for expression of properties associated with the transformed phenotype including immortalization. The integrated viral sequences in an anchorage-independent line of viral-transformed human keratinocytes have been found to be contained on two BamHI fragments of about 6.9 and 5.2 kb. In the larger fragment the viral sequences were present as two tandemly repeated subgenomic fragments containing the viral origin/promoter region with nucleotide alterations that affect enhancer function, the origin of replication and T antigen binding site 1. The viral early gene promoter in one integrant gave rise to an unspliced fusion transcript comprised of a short portion of the viral early gene leader sequence and the flanking human sequences. The smaller fragment consisted of full-length SV40 containing a nine-nucleotide insertion in the C-terminal portion of the SV40 T antigen, a region involved in the regulation of viral host range.
High-power active interference suppression in magnetic particle imaging

For angiography, stem cell imaging, and cancer imaging, magnetic particle imaging (MPI) can replace conventional techniques due to its safety in vivo, exquisite image contrast, and high detection sensitivity. However, compared to the theoretical physical sensitivity limit of a MPI scanner with 1 mm3 resolution using image 17 nm iron oxide nanoparticles, which lies between 100 nM and 1 μM1, the detection sensitivity for current MPI systems is worse by over 4 orders of magnitude. Factors contributing to this lack of sensitivity include non-optimal noise matching and feedthrough interference, of which the latter is a more dominant effect due to spectral overlap between the interfering signals and particle signals. Gleich et al., Schmale et al. and the authors of this study have previously attempted to decrease the interference through high-power filters and reducing capacitor distortion. In this work, we attempt to actively cancel interfering magnetic fields through the use of a feedforward transformer coupling circuit.
Synthesis of 2-acetamido-2-deoxy-4-O-(2-O-methyl-β-D-galactopyranosyl)-d-glucopyranose (N-acetyl-2′-O-methyllactosamine)

Abstract 1,3,4,6-Tetra- O -acetyl-2- O -methyl- d -galactopyranose, prepared from known methyl 6- O -acetyl-3,4- O -isopropylidene-β- d -galactopyranoside, was treated with hydrogen bromide in dichloromethane to afford 3,4,6-tri- O -acetyl-2- O -methyl-α- d -galactopyranosyl bromide. Condensation with benzyl 2-acetamido-3,6-di- O -benzyl-2-deoxy-α- d -glucopyranoside in acetonitrile in the presence of mercuric cyanide gave an approximately 1:1 mixture of benzyl 2-acetamido-3,6-di- O -benzyl-2-deoxy-4- O -(3,4,6-tri- O -acetyl-2- O -methyl-β- ( 8 ) and -α- d -galactopyranosyl)-α- d -glucopyranoside. O -Deacetylation and catalytic hydrogenolysis of the benzyl group furnished 2-acetamido-2-deoxy-4- O -(2- O -methyl-β- and α- d -galactopyranosyl)- d -glucopyranose. Alternatively, benzyl 2-acetamido-3,6-di- O -benzyl-2-deoxy-4- O -β- d -galactopyranosyl-α- d -glucopyranoside was treated with tert -butyldiphenyl-chlorosilane in N,N -dimethylformamide, in the presence of imidazole, to give a 6′- O - tert -butyldiphenylsilyl intermediate that was in turn converted into its 3′,4′- O -isopropylidene acetal. Methylation with methyl iodide-silver oxide in N,N -dimethylformamide, followed by removal of the silyl and isopropylidene groups gave benzyl 2-acetamido-3,6-di- O -benzyl-2-deoxy-4- O -(2- O -methyl-β- d -galactopyranosyl)-α- d -glucopyranoside, which was further characterized as its triacetate 8 .
Mineral inclusions in Brazilian diamonds

Abstract Minerals included in diamonds from several localities in Brazil have been examined. The minerals observed are olivine, enstatite, chrome-pyrope and pyrope-almandine. These minerals have similar compositions to those previously reported for inclusions from other worldwide localities. In addition rutile, ilmenite, zircon, quartz and pyrrhotite occur as inclusions. This is the first record of ilmenite and zircon in natural diamond. The ilmenite is unique compared to most kimberlite ilmenites in that it contains no appreciable content of magnesium. The presence of quartz as an inclusion is unusual.
Development of Bifunctional Stilbene Derivatives for Targeting and Modulating Metal-Amyloid-β Species

Amyloid-β (Aβ) peptides and their metal-associated aggregated states have been implicated in the pathogenesis of Alzheimer’s disease (AD). Although the etiology of AD remains uncertain, understandi...
Statistical Analysis of Multiserver Queueing Simulations

This paper presents methods for computing point and interval estimates of descriptors of simulated queueing systems. The methods rely on the renewal process representation of certain queueing models. Two suggested procedures combine sample state times and job completion counts data to produce estimates with desirable statistical properties. One procedure uses linear combinations of the data to derive minimum length interval estimates. The other derives the maximum likelihood estimates of three descriptors (transformations of which can be used to give maximum likelihood esti mates of a variety of other system descriptors). The paper also describes how to extend these results to other queueing systems and illustrates the approach for a queueing system with finite waiting room.
WSN-SA: Design foundations for situational awareness systems based on sensor networks

WSN-SA is a Wireless Sensor Networks (WSN) framework that is been proposed to support rescue operations in collapsed structures, such as houses and buildings, after natural and human-made disasters. The sensors and actuators are deployed prior to the disaster and ideally such sensor network is a required infrastructure of any building. Such SA systems can help to indicate how to distribute the rescue resources and how to identify imminent risks for rescuers and survivors. So far, few situational awareness (SA) systems based on WSNs have been proposed and no long-term realization of such systems has been reported. The goal of this work is to provide the foundations to change this reality so it would be possible to see a SA system accompanying each existing fire system. To this end, a strong emphasis is given to a) the achievement of low total cost of ownership (TCO), b) reliability, c) and expandability for the adopted SA solution.
Abstract A16: Stromal LOX promotes TGFβR2 null breast cancer metastasis

To understand how loss of TGF-β signaling in cancer cells promotes tumor progression, we are evaluating modifications to the extracellular matrix in TGF-β type II receptor KO tumors. Tumor cell invasion is a dynamic process which is regulated by many microenvironmental influences such as ECM composition, MMP activity, and exposure of proper integrin binding sites. Crosslinking of collagen fibers increases the overall stiffness of affected tissue providing the mechanical force necessary for tumor cell migration and invasion. Lysyl oxidase is a potent extracellular enzyme that crosslinks collagen and elastin fibers. The study of human breast cancer cell lines shows that highly invasive cells express higher levels of lysyl oxidase and treatment with a lysyl oxidase inhibitor significantly decreases cellular invasion. Recent reports suggest that hypoxia induced metastasis is facilitated by lysyl oxidase crosslinking of the extracellular matrix. TGF-β is another molecule that is known to promote lysyl oxidase expression and will be the focus of our studies. In this study we utilize transgenic mice which express PyMT under a mammary epithelial specific promoter and have the type II TGF-β receptor conditionally deleted from mammary epithelial cells. Prior to tumor palpation, we see an increase in collagen deposition as well as tissue tensile strength indicating the presence of a higher degree of collagen crosslinking. In PyMT tumors originating from the RII KO mammary glands, increased deposition and maturation of collagen is present in the tumor microenvironment. However, this is not correlated with an increased expression of collagen genes. Subsequent analysis has shown an increased expression and activity of lysyl oxidase present in these TGFβR2KO PyMT tumors. Increased levels of lysyl oxidase are correlated with increased levels of available TGF-β in the RII KO tumors. Upon in vivo inhibition of lysyl oxidase, with beta-aminoproprionitrile, we see a significant decrease in tumor metastasis to the lungs through the inability to escape into the vasculature. Interestingly, these phenotypes are not driven by hypoxia, as shown in previous publications, and instead appear to be driven by TGFβ signaling in the stroma of these tumors. With the source of the TGFβ driving the increase expression of stromal LOX appears to be infiltrating immune cells, MDSCs. This work points to a new paradigm of LOX induction in tumors and presents a new therapeutic target group for LOX inhibition outside of patients presenting with hypoxic tumors. Citation Format: Michael W. Pickup, Philip Owens, Agnes Gorska, Anna Chytil, Valerie Weaver, Harold Moses. Stromal LOX promotes TGFβR2 null breast cancer metastasis. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Invasion and Metastasis; Jan 20-23, 2013; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2013;73(3 Suppl):Abstract nr A16.
Fetal exposure to synthetic oxytocin and the relationship with prefeeding cues within one hour postbirth

Abstract Background Prefeeding cues are oral-motor neurobehaviors that communicate feeding readiness, and the ability to self-comfort and regulate behavioral state. Intrapartum and newborn procedures have been associated with altered frequency and emergence of prefeeding cues soon after birth. Intrapartum synthetic oxytocin is commonly used for labor induction/augmentation in the US, yet there is little research on potential effects on infant neurobehavioral cues. Aims To explore whether fetal exposure to synthetic oxytocin was associated with the infant's level of prefeeding organization shortly after birth. Study design Cohort. Subjects A convenience sample of 47 healthy full-term infants (36 exposed and 11 unexposed to intrapartum synthetic oxytocin) was studied. Exclusion criteria Fetal distress, vacuum/forceps, cesarean, and low Apgar. Outcome measures Videotapes of infants (45–50min postbirth) were coded for frequency of eight prefeeding cues, and analyzed by level of prefeeding organization. Results In general, fewer prefeeding cues were observed in infants exposed versus unexposed to synOT and differences were significant for brief and sustained hand to mouth cues [incidence rate ratio (95% CI)=0.6 (0.4, 0.9) and 0.5 (0.2, 0.9), respectively]. Forty-four percent of exposed infants demonstrated a low level of prefeeding organization, compared to 0% from the unexposed group. In contrast, 25% of exposed versus 64% of unexposed infants demonstrated high prefeeding organization. After adjusting for covariates, exposed infants were at 11.5 times (95% CI=1.8–73.3) the odds of demonstrating low/medium versus high levels of prefeeding organization compared to unexposed infants. Conclusions Newborn neurobehavioral cues may be sensitive to intrapartum synthetic oxytocin.
2-D Light Diffraction from CCD and Intensified Reticon Multichannel Detectors Causes Spectrometer Stray Light Problems

Intensified diode arrays and charge-coupled detectors (CCD) which are used as multichannel detectors for spectroscopy exhibit strong 2-D diffraction of light due to the micro-channel plate intensifier and the CCD surface microelectronic structures. The strong 2-D diffraction of light by the intensified diode arrays shows hexagonal symmetry due to the hexagonal packing of the hollow glass fibers of the micro-channel plate intensifier. The 2-D diffraction of light from the CCD detectors shows square symmetry due to the almost square symmetry of the individual surface microelectronic structures. Light incident on the detector surfaces is diffracted into numerous angles which depend upon the incident angle and the light wavelength. This diffracted light can be redispersed and/ or reflected and scattered by optical elements inside the spectrometer. This diffracted light can then contribute to spectrometer diffuse stray light or it can be directly reimaged onto the detector to cause spectral artifacts. Backthinned CCD detectors do not show 2-D light diffraction and thus avoid these 2-D diffraction stray light limitations.
Note on self‐regulating systems and stress

If the components of performance of self-regulating systems, for example detection and identification of the stimulus and availability of response, can be precisely defined for the gross behavior of an organism responding to its environment, the study of the effects of stress can be made correspondingly differentiated and precise. In particular, it would be interesting to know whether certain nonspecific responses, sometimes interpreted as anxiety symptoms, are attempts of the organism to get more feedback from the environment.
Cytoplasmic calcium measurement in rotavirus enterotoxin-enhanced green fluorescent protein (NSP4-EGFP) expressing cells loaded with Fura-2.

Abstract The green fluorescent protein (GFP) and its analogs are standard markers of protein expression and intracellular localization of proteins. The fluorescent properties of GFP complicate accurate measurement of intracellular calcium using calcium sensitive fluorophores, which show a great degree of spectral overlap with GFP, or their K d values are too high for accurate measurement of subtle changes in cytoplasmic calcium concentrations. Here we describe a simple modification of the standard microscope-based Fura-2 calcium-imaging technique which permits the quantitative measurement of intracellular calcium levels in cells expressing enhanced green fluorescent protein (EGFP) fusion proteins. Longpass emission filtering of the Fura-2 signal in cells expressing an EGFP fusion protein is sufficient to eliminate the EGFP–Fura-2 emission spectra overlap and allows quantitative calibration of intracellular calcium. To validate this technique, we investigated the ability of rotavirus enterotoxin NSP4-EGFP to elevate intracellular calcium levels in mammalian HEK 293 cells. We show here that inducible intracellular expression of NSP4-EGFP fusion protein elevates basal intracellular calcium more than two-fold by a phospholipase C (PLC) independent mechanism.
Brown picket fences: The immigrant narrative and 'giving back' among the Mexican-origin middle class

In 2000, Latinos superseded blacks as the largest racial/ethnic minority group in the US, comprising nearly 13 percent of the US population, and by 2050, demographers estimate that their population will have reached 25 percent. Given the size and growth of the Latino population, an important sociological concern is the extent to which the adult children of Latino immigrants incorporate into the US social structure. Focusing on the largest ethnic Latino group, Mexicans (and specifically, the Mexican middle class), this article studies one aspect of the incorporation process — the extent to which they `give back' to co-ethnics. Based on 40 face-to-face, in-depth interviews with 1.5- and second-generation middle-class Mexicans, the study finds that those who grew up poor and achieved middle-class status within one generation exhibit a collectivist orientation, and `give back' to poorer kin, co-ethnics and the larger ethnic community. By contrast, those who grew up in middle-class households adopt an individu...
Accumulation of Nitrogen and Dry Matter by Soybean Seeds with Genetic Differences in Protein Concentration

Soybean [Glycine max (L.) Merrill] yields often decline as seed protein levels increase, but the processes responsible are not clearly understood. We compared dry matter and N accumulation by individual seeds of three high protein genotypes (K 1431, KS 4402sp, NE 3396) and three commercial cultivars (Pennyrile, Flyer, Hutcheson) in the field near Lexington, KY (38° 01' N lat; 84° 35' W long) for 3 yr to determine if increasing protein concentration decreased the seed growth rate. Plants were grown in 76.2-cm rows using conventional production practices and overhead irrigation to minimize soil moisture deficits. The rate of dry matter accumulation by individual seeds (SGR DM ) varied from 4.2 to 6.1 mg seed -1 d -1 and this variation was closely associated with mature seed size, but it was not affected by seed N concentration. The rate of N accumulation (SGR N , mg N seed -1 d -1 ) was closely associated with seed N concentration at maturity across all genotypes and years (r 2 = 0.76). Thus, SGR N and SGR DM seemed to vary independently as the N concentration in mature seeds increased. The duration of seed filling (estimated by the effective filling period) was not related to mature seed N concentration. Since higher seed N concentration had no effect on the rate or duration of seed dry matter accumulation by individual seeds, the purported negative effect of seed protein levels on yield may be more closely associated with whole plant phenomena than those operating at the individual seed level.
On lattice-ordered rings in which the square of every element is positive

It is shown that a unital lattice-ordered ring in which the square of every element is positive is embeddable in a product of totally ordered rings provided it is archimedean, semiperfect, or π-regular. Also, some canonical examples of unital l-domains with squares positive that are not totally ordered are discussed.
Compressive deformation of porous lunar regolith

Abstract Compressive properties of porous lunar regolith were tested. It was hypothesized that final porosity could be controlled by changing the initial powder particle size during pressing and sintering. A sintering temperature of 1200 °C for 20 min was found to be optimum for densification. Controlling the size of the powder particle changed the porosity of the sintered body, and samples were made with density ranging from 99.0±0.5% to 92±2% of theoretical density. Compression tests showed 99.0±0.5% and 92±2% dense samples had an average failure stress of 232 MPa and 103.2 MPa, respectively. The average hardness of the sintered lunar regolith was found to be 1027 HV0.1.
Thermoelectrical Modeling of Wavelength Effects on Photovoltaic Module Performance—Part II: Parameterization

Intervals of the incident solar spectrum associated with long wavelengths do not contribute to electricity production due to their low energy levels. However, light with such wavelengths partially passes through the module layers, while the remainder is either reflected or absorbed as heat into them. Absorbed heat increases the solar module temperature and reduces its efficiency. In Part I, a thermoelectrical model is proposed in order to study the effects of the individual wavelengths on the photovoltaic (PV) module performance. In this paper, a method to characterize the model is proposed. A case study that shows the extraction and the derivation of all required parameters for the model is presented. The experiments are conducted on a lab-built monocrystalline silicon PV module. An optical model is presented to predict the optical properties of the module layers. It is found that characterizing the model using the proposed parameterization methodology leads to predicted results that are consistent with the experimental measurements.
Covering the edges with consecutive sets

The following question is answered in this note : for which graphs G can the vertices of G be linearly ordered so that all the minimal vertex covers of G are consecutvie sets?
Liquid-liquid segmented flows in polymer microfluidic channels

Liquid-liquid segmented flows in microchannels fabricated on polymer test chips were investigated experimentally. Polymer test chips were prepared using hot embossing of polycarbonate (PC) sheets with micro-milled brass mold inserts. Three different configurations of microchannels were prepared with injection to test channels expansion ratios of 16, 4 and 2 and a fixed test channel geometry. Deionized water with blue food-coloring dye (1% v/v) was used as a dispersed fluid at flow rates (QD ) between 0.5 and 60 μl/min. The carrier fluid was perfluorocarbon (FC 3283) with nonionic fluorous-soluble surfactant (Perfluorooctanol, 10% v/v) at flow rates (QC ) between 3 and 25 μl/min. The two fluids were injected separately into the chips. Droplet and Plug flows with transient Irregular Segmented flows between two flow regimes were mainly observed in the test channels of the three different chips. Flow pattern maps and transitions between flow regimes were determined in terms of a fixed homogeneous carrier fluid volumetric flow ratio (βC ) to compare the effect of the expansion ratios from the injection to the test channels. The droplet and plug regimes were shifted to higher carrier and lower dispersed fluid superficial velocities and the plug flow regime was broader with the lower expansion ratio channels. The transient irregular segmented flow was favored in the higher expansion channel ratio and the interval of transient irregular segmented flow between droplet and plug flow regimes were shorter for the low expansion channel ratios. This is evidence that flow regime maps in micro-channels are not universal and depend on the configuration part of the micro-injection system. The length of the dispersed segmented flows and the distance between consecutive droplets or plugs as a function of βC were determined by image processing of frames acquired via CCD camera with bright field illumination. The average length of the dispersed fluid was shown to scale approximately with βC to the −1.2 power. Velocities of the dispersed droplet and plug flows were measured using double-pulsed laser illumination and were found to be 1.25 ± 0.049 and 1.46 ± 0.077 times faster than the superficial velocity of the segmented flow respectively. Two-phase pressure drop measurements were also carried out for all flow regimes and associated trends were correlated with changes in flow topology. Comparisons of experimental pressure drop with the predictions for a modified Lockhart-Martinelli correlation were also made.Copyright © 2009 by ASME
Molecular characterization of the eps gene cluster of Pseudomonas solanacearum and its transcriptional regulation at a single promoter

Production of EPS I, an unusual exopolysaccharide virulence factor of the phytopathogen Pseudomonas solanacearum, requires the 18 kb eps gene cluster. DNA sequence analysis of the first seven genes of eps (epsAPBCDEF), subcellular localization of their products in maxicells, and phoA fusion analysis showed that: (i) epsA, epsB, epsE, and epsF encode exported or membrane-associated proteins probably involved in polymerization and/or export of EPS I; (ii) epsC and epsD encode soluble enzymes probably involved in synthesis of sugar components of EPS I (N-acetylgalactosaminuronic acid and possibly N-acetyltrideoxygalactose, respectively); and (iii) epsP probably encodes a phosphatase involved in EPS I production in an unknown way. Non-polar insertional mutagenesis showed that most, if not all, of these eps genes are absolutely required for production of EPS I. Using random eps::lacZ fusions and primer extension we located a transcription start site and promoter upstream of epsA. Analysis of a plasmid with this promoter fused to lacZ showed that a 140 bp regulatory region upstream of the eps transcription start site was sufficient for normal regulation of eps transcription by the multicomponent virulence gene regulatory network of P. solanacearum. Deletion of this eps promoter from a plasmid-borne epsAPBCDE::lacZ fusion reduced its expression 10-fold, indicating that this promoter alone is responsible for regulated transcription of an eps operon composed of at least epsAPBCDE. Analysis of genomic and plasmid-borne eps::lacZ fusions suggested that most remaining eps genes are part of this same operon or, and this is less likely, comprise a second co-ordinately regulated eps operon.
Real‐Time Functional Magnetic Resonance Imaging

A recursive algorithm suitable for functional magnetic resonance imaging (FMRI) calculations is presented. The correlation coefficient of a time course of images with a reference time series, with the mean and any linear trend projected out, may be computed with 22 operations per voxel, per image; the storage overhead is four numbers per voxel. A statistical model for the FMRI signal is presented, and thresholds for the correlation coefficient are derived from it. Selected images from the first real-time functional neuroimaging experiment (at 3 Tesla) are presented. Using a 50-MHz workstation equipped with a 14-bit analog-to-digital converter, each echo planar image was acquired, reconstructed, correlated, thresholded, and displayed in pseudocolor (highlighting active regions in the brain) within 500 ms of the RF pulse.
Infrared Spectra of Oriented and Nonoriented Layered Double Hydroxides in the Range from 4000 to 250 cm-1, with Evidence for Regular Short-Range Order in a Synthetic Magnesium−Aluminum LDH with Mg:Al = 2:1 but Not with Mg:Al = 3:1

We have extended the experimental examination of layered double hydroxides of the types Mg2Al(OH)6X and Mg3Al(OH)8X, both as isotropic pellets and as oriented supported specimens, to cover the entire range from 4000 to 250 cm-1 by the use of CsI pellets and CdTe and polyethylene supports and compared our results with theoretical expectations. Close inspection of the group theoretically predicted vibrational modes for these materials shows that formal allowedness, while necessary, is not sufficient for spectroscopic intensity. The OH z-translational mode occurs around 700 cm-1, while the x,y-translations and the OH rotation (MOH bend) cover a broad region from around 1000 cm-1 down. The hydroxide O−H stretching mode, which is suppressed by orientation, is concentrated at the higher end of the total O−H stretching region. Aged material of the type Mg2Al(OH)6X shows reproducible structure around 400 cm-1 both when X is chloride and when X is 1/4ferrocyanide. This structure is weak or absent in freshly prepar...
The Structure of Eukaryotic Translation Initiation Factor-4E from Wheat Reveals a Novel Disulfide Bond

Eukaryotic translation initiation factor-4E (eIF4E) recognizes and binds the m7 guanosine nucleotide at the 5′ end of eukaryotic messenger RNAs; this protein-RNA interaction is an essential step in the initiation of protein synthesis. The structure of eIF4E from wheat (Triticum aestivum) was investigated using a combination of x-ray crystallography and nuclear magnetic resonance (NMR) methods. The overall fold of the crystallized protein was similar to eIF4E from other species, with eight β-strands, three α-helices, and three extended loops. Surprisingly, the wild-type protein did not crystallize with m7GTP in its binding site, despite the ligand being present in solution; conformational changes in the cap-binding loops created a large cavity at the usual cap-binding site. The eIF4E crystallized in a dimeric form with one of the cap-binding loops of one monomer inserted into the cavity of the other. The protein also contained an intramolecular disulfide bridge between two cysteines (Cys) that are conserved only in plants. A Cys-to-serine mutant of wheat eIF4E, which lacked the ability to form the disulfide, crystallized with m7GDP in its binding pocket, with a structure similar to that of the eIF4E-cap complex of other species. NMR spectroscopy was used to show that the Cys that form the disulfide in the crystal are reduced in solution but can be induced to form the disulfide under oxidizing conditions. The observation that the disulfide-forming Cys are conserved in plants raises the possibility that their oxidation state may have a role in regulating protein function. NMR provided evidence that in oxidized eIF4E, the loop that is open in the ligand-free crystal dimer is relatively flexible in solution. An NMR-based binding assay showed that the reduced wheat eIF4E, the oxidized form with the disulfide, and the Cys-to-serine mutant protein each bind m7GTP in a similar and labile manner, with dissociation rates in the range of 20 to 100 s−1.
Total dissolved nitrogen in seawater: a new-high-temperature combustion method and a comparison with photo-oxidation

Abstract A new high-temperature combustion method, using a slightly modified commercially available nitrogen analyzer, is presented for the measurement of total dissolved nitrogen in seawater. The technique provides combustion of seawater at 1110°C under ultrapure oxygen saturation. All chemically bound dissolved nitrogen compounds in the seawater sample are oxidized to nitric oxide, which is directly measured with a chemiluminescent detector. The method has sensitivity below 1 ng N and appears near absolute in accuracy by virtue of its complete recovery (94–102%) of all tested inorganic, organic, and recalcitrant nitrogen compounds dissolved in a natural seawater diluent. Results from this high-temperature method are compared with those from the often-used, but often-criticized, photo-oxidation method. A strong defense is made for the properly administered photo-oxidation of natural seawater samples. The comparison also provides a more credible insight into the limitations of the effectiveness of the photo-oxidation method. The implications of this method of comparison, and the resulting estimates of dissolved organic nitrogen concentrations in seawater, are discussed with reference to other commonly cited methods for total dissolved nitrogen in natural waters. Particular reference is made to alkaline persulfate digestions and to other thermal combustion methods. In the case of the natural seawater samples, all nutrient properties, including dissolved organic phosphorus, are provided to characterize fully these seawaters for comparison with other published data.
Comparing ordered-entry queues with heterogeneous servers

We study a queueing system withm exponential servers with distinct service rates. Jobs arrive at the system following an arbitrary point process. Arrived jobs receive service at the first unoccupied server (if any) according to an entry order π, which is a permutation of the integers 1, 2,...,m. The system has a finite buffer capacity. When the buffer limit is reached, arrivals will be blocked. Blocked jobs will either be lost or come back as New arrivals after a random travel time. We are concerned with the dynamic stochastic behavior of the system under different entry orders. A partial ordering is established among entry orders, and is shown to result in some quite strong orderings among the associated stochastic processes that reflect the congestion and the service characteristics of the system. The results developed here complement existing comparison results for queues with homogeneous servers, and can be applied to aid the design of conveyor and communication systems.
Collaborative Collection Management in a High-density Storage Facility

This case study reviews selected collection management issues encountered in a collaboratively managed high-density remote storage facility. In 2000, four Colorado institutions—the University of Colorado at Boulder, the University of Colorado at Denver, the University of Colorado Health Sciences Center, and the University of Denver—opened a shared high-density storage facility. This mix of public and private institutions agreed to collaborative collection management, including a nonduplication policy and the granting of direct access to stored materials for nonparticipating institutions through a statewide union catalog. Ownership of stored materials, selection of items for storage, operational management, and online and physical access proved to be challenging policy issues requiring committees, patience, and compromise to resolve.
Adsorption of Water-Soluble Polymers on High Surface Area Clays

The adsorption of water-soluble polymers, predominately of the polysaccharide type, on attapulgite, bentonite and berea sand/bentonite (15 wt.%) agglomerated substrates and on deflocculated bentonite suspensions has been conducted. In the agglomerated substrate studies the molecular weight of derivated polysaccharides was an important factor; the lower the molecular weight the greater the adsorption. Molecular weight was not important in adsorption on deflocculated bentonite substrates. Several interesting observations on the adsorption of anionic polymers from high salinity solutions have been made. 36 refs.
Nurturing Positive Mental Health: Mindfulness for Wellbeing in Counseling

As increasing attention has been given in the past decade to positive psychology, this has likewise been directed toward understanding methods of nurturing positive mental health. These methods have moved toward empowering clients in the development of skills to enhance their own sense of wellbeing (Khong, Counseling and Spirituality, 25, 67–84, 2006). Advances in neurosciences are adding to this understanding, especially through the power of neuroimaging. Mindfulness training and self-compassion are key practices undergoing development for empowering clients in ways to nurture their own positive mental health. Counselors who become familiar with these practices and ways in which they promote positive mental health can gain new understanding and methods for assisting clients and thereby extend their therapeutic effectiveness. Counselors can teach clients practices that can serve to enhance coping capabilities and to reduce suffering.
On the Restricted Isometry of deterministically subsampled Fourier matrices

Matrices satisfying the Restricted Isometry Property (RIP) are central to the emerging theory of compressive sensing (CS). Initial results in CS established that the recovery of sparse vectors x from a relatively small number of linear observations of the form y = Ax can be achieved, using a tractable convex optimization, whenever A is a matrix that satisfies the RIP; similar results also hold when x is nearly sparse or the observations are corrupted by noise. In contrast to random constructions prevalent in many prior works in CS, this paper establishes a collection of deterministic matrices, formed by deterministic selection of rows of Fourier matrices, which satisfy the RIP. Implications of this result for the recovery of signals having sparse spectral content over a large bandwidth are discussed.
TAP1-dependent peptide translocation in vitro is ATP dependent and peptide selective

T cells detect infection of cells by recognizing peptide fragments of foreign proteins bound to class I molecules of the major histocompatibility complex (MHC) on the surface of the infected cell. MHC class I molecules bind peptide in the endoplasmic reticulum, and analysis of mutant cells has demonstrated that an adequate supply of peptides requires the presence of two genes in the MHC class II locus that encode proteins called transporters associated with antigen processing (TAP) 1 and 2. TAP1 and TAP2 are members of the ATP-binding cassette family of membrane translocators. In this study, we demonstrate in a cell-free system that TAP1 is part of an ATP-dependent, sequence-specific, peptide translocator.
Toxicity of Three Polyethoxylated Tallowamine Surfactant Formulations to Laboratory and Field Collected Fairy Shrimp, Thamnocephalus platyurus

Polyethoxylated tallowamine (POEA) is a non-ionic surfactant used in herbicide formulations to increase the efficacy of active ingredients. POEA promotes penetration of herbicide active ingredients into plant cuticles, and in animal species is known to cause alterations in respiratory surfaces. POEA use has increased recently with the advent of “Roundup-Ready” crops; however, its potential effects on aquatic invertebrates are relatively unknown. The aquatic macroinvertebrate Thamnocephalus platyurus (Crustacea, Anostraca) was used to assess the acute toxicity of POEA. Three formulations of POEA consisting of a 5:1, 10:1, and 15:1 average oxide:tallowamine were used in this study. All POEA formulations were found to be extremely toxic to T. platyurus with 48-h LC50 concentrations as low as 2.01 μg/L for 15:1. POEA toxicity increased as the tallowamine chain length was reduced, whereas the oxide chain length appeared to only slightly increase toxicity. Based on these results, POEA has the potential to adversely affect aquatic organisms in areas in which it is used.
The intergral fast reactor-an overview

The Integral Fast Reactor (IFR) is a system that consists of a fast-spectrum nuclear reactor that uses metallic fuel and liquid-metal (sodium) cooling, coupled with technology for high-temperature electrochemical recycling, and with processes for preparing wastes for disposition. The concept is based on decades of experience with fast reactors, adapted to priorities that have evolved markedly from those of the early days of nuclear power. It has four essential, distinguishing features: efficient use of natural resources, inherent safety characteristics, reduced burdens of nuclear waste, and unique proliferation resistance. These fundamental characteristics offer benefits in economics and environmental protection. The fuel cycle never involves separated plutonium, immediately simplifying the safeguarding task. Initiated in 1984 in response to proliferation concerns identified in the International Nuclear Fuel Cycle Evaluation (INFCE, 1980), the project has made substantial technical progress, with new potential applications coming to light as nuclear weapons stockpiles are reduced and concerns about waste disposal increase. A breakthrough technology, the IFR has the characteristics necessary for the next nuclear age.
B → F + X decay and pseudoscalar decay constants of explicitly flavored heavy mesons☆

Abstract If the current theoretical pictures of explicitly flavored heavy mesons are quantitatively correct, we expect that the branching ratio of B → F + X (anything) may be 6 percent even in a conservative estimate. Accurate measurement of this branching ratio will determine the value of the pseudoscalar decay constant fF, of the wave function at origin of the s wave c s bound state in the potential picture, and help to clarify dynamical properties of heavy meson binding.
Effects of Diet on Urinary 1‐Ascorbic Acid in the Human

The relationship of dietary vitamin C to that in the urine has not been established. Vitamin C intake and 24-hr urinary 1-ascorbate excretion were measured in healthy, human, Caucasian, female subjects (ages 22–26 yr). Modifications were made in the measurement of 1-ascorbic acid in the urine. The correlation of dietary vitamin C to that excreted in the urine was highly significant (P < 0.001; r = 0.952). The regression equation is: y = -1.2970 + 0.1863x. The average intake of vitamin C was 146.5 ± 117.6 mg (standard deviation) (range 42–424 and the average amount in a 24-hr urine sample was 26.0 ± 23.0 mg (range 5–71). The average percentage of dietary intake excreted per day was 17.04 ± 9.43 (range 6.1–29.4). Data presented here should help establish guidelines for interpreting urinary 1-ascorbic acid concentrations. If dietary data are available, it is suggested that these guidelines be expressed as a percentage of intake. Additional data are needed.