cssi/SciSciGPT-SciSciNet huggingface dataset:
On the significance of remodeling space and activation rate changes in bone remodeling

This paper quantifies the relative contributions of the remodeling space and the accumulation of Haversian canals to bone porosity at various ages. It also examines the importance of variations in the rate of bone remodeling that occur during growth and aging, and as a result of trauma and disease. The dependence of the remodeling space (cavities due to resorbing, reversing, and refilling BMUs) and the Haversian canal components of porosity on the Basic Multicellular Unit (BMU) activation frequency are mathematically formulated. A graph is developed using data for the cortex of the human rib which shows the extent to which porosity is primarily due to the remodeling space in children, and to accumulated Haversian canals in adults. It is shown that the diminution of activation frequency between birth and age 35 contributes to the concurrent increase in bone volume fraction, and the increase in activation frequency after age 35 contributes to the subsequent decline of bone volume fraction. An equation is derived for determining the time rate of change of activation frequency using two fluorochrome labels.
Computational Characterization of Mutations in Cardiac Troponin T Known to Cause Familial Hypertrophic Cardiomyopathy

Cardiac Troponin T (cTnT) is a central modulator of thin filament regulation of myofilament activation. The lack of structural data for the TNT1 tail domain, a proposed α-helical region, makes the functional implications of the FHC mutations difficult to determine. Studies have suggested that flexibility of TNT1 is important in normal protein-protein interactions within the thin filament. Our groups have previously shown through Molecular Dynamics (MD) simulations that some FHC mutations, Arg92Leu(R92L) and Arg92Trp(R92W), result in increased flexibility at a critical hinge region 12 residues distant from the mutation. To explain this distant effect and its implications for FHC mutations, we characterized the dynamics of wild type and mutational segments of cTnT using MD. Our data shows an opening of the helix between residues 105-110 in mutants. Consequently, the dihedral angles of these residues correspond to non-α-helical regions on Ramachandran plots. We hypothesize the removal of a charged residue decreases electrostatic repulsion between the point mutation and surrounding residues resulting in local helical compaction. Constrained ends of the helix and localized compaction results in expansion within the nearest non-polar helical turn from the mutation site, residues 105-109.
Capacitive current switching with circuit breakers

ALTHOUGH POWER circuit breakers are designed primarily to interrupt heavy inductive short-circuit currents, system growth in recent years has produced a greatly increased requirement of interrupting relatively lighter currents associated with the switching of capacitive kilovolt-amperes. This capacitive kilovolt-ampere requirement has manifested itself in long-distance high-voltage transmission lines, in relatively long high-voltage cables, and in large-size shunt-capacitor banks which are becoming a common fundamental unit in system design and operation. There is not necessarily a relationship between the ability of a circuit breaker to interrupt short-circuit currents and its ability to switch capacitance currents. It is recognized widely that high-frequency voltage and current oscillations may be produced which, if uncontrolled, may result in damage to apparatus or system outages.
The physics of symbols: bridging the epistemic cut.

Abstract Evolution requires the genotype–phenotype distinction, a primeval epistemic cut that separates energy-degenerate, rate-independent genetic symbols from the rate-dependent dynamics of construction that they control. This symbol–matter or subject–object distinction occurs at all higher levels where symbols are related to a referent by an arbitrary code. The converse of control is measurement in which a rate-dependent dynamical state is coded into quiescent symbols. Non-integrable constraints are one necessary condition for bridging the epistemic cut by measurement, control, and coding. Additional properties of heteropolymer constraints are necessary for biological evolution.
Effects of cholesterol oxides on LDL receptors in cultured rabbit aortic smooth muscle cells

Abstract The efficiency of receptor-mediated low-density lipoprotein (LDL) uptake and degradation has been implicated in the development of atherosclerosis. It has previously been shown that cholesterol oxides have more effect on the feedback control of cholesterol biosynthesis than does cholesterol per se on a molecule-for-molecule basis. Cholesterol oxides may also modify the expression or function of the LDL receptors, resulting in alteration in cholesterol homeostasis. Rabbit aortic smooth muscle cells were preincubated in 5% lipoprotein-deficient medium for 24 hours and then incubated with 1 or 5 μg/ml purified cholesterol or cholesterol oxides, including 25-hydroxycholesterol, 7-ketocholesterol, cholestane-3β,5α,6β-triol, and cholesterol 5α, 6α-epoxide for 12 to 24 hours. The uptake of 125 I-LDL was significantly suppressed in a dose-dependent fashion to 67% of the control value by 25-hydroxycholesterol at 1 μg/ml and to 53% at 5 μg/ml after the 24-hour incubation period. Other cholesterol oxides also had inhibitory effects on the LDL uptake at 5 μg/ml. At these concentrations cholesterol oxides additionally inhibited cellular degradation of LDL and the fractional turnover rate of LDL was prolonged.
Enhanced spatial models for predicting the geographic distributions of tick-borne pathogens

Disease maps are used increasingly in the health sciences, with applications ranging from the diagnosis of individual cases to regional and global assessments of public health. However, data on the distributions of emerging infectious diseases are often available from only a limited number of samples. We compared several spatial modelling approaches for predicting the geographic distributions of two tick-borne pathogens: Ehrlichia chaffeensis, the causative agent of human monocytotropic ehrlichiosis, and Anaplasma phagocytophilum, the causative agent of human granulocytotropic anaplasmosis. These approaches extended environmental modelling based on logistic regression by incorporating both spatial autocorrelation (the tendency for pathogen distributions to be clustered in space) and spatial heterogeneity (the potential for environmental relationships to vary spatially). Incorporating either spatial autocorrelation or spatial heterogeneity resulted in substantial improvements over the standard logistic regression model. For E. chaffeensis, which was common within the boundaries of its geographic range and had a highly clustered distribution, the model based only on spatial autocorrelation was most accurate. For A. phagocytophilum, which has a more complex zoonotic cycle and a comparatively weak spatial pattern, the model that incorporated both spatial autocorrelation and spatially heterogeneous relationships with environmental variables was most accurate. Spatial autocorrelation can improve the accuracy of predictive disease risk models by incorporating spatial patterns as a proxy for unmeasured environmental variables and spatial processes. Spatial heterogeneity can also improve prediction accuracy by accounting for unique ecological conditions in different regions that affect the relative importance of environmental drivers on disease risk.
Pilot 05: Distributed Architecture for Robust Real-Time Progression Evaluation and Improvement

Real-time offset tuning can provide an almost optimal operation while capitalizing on the existing knowledge and familiarity of traffic engineers and personnel with the current actuated control system. The real-time offset tuning concept was introduced several years ago by one of the authors of this paper. Advantages and disadvantages of the concept were discussed in subsequent papers. The concept was taken further for implementation by other researchers within the ACS Lite tactical-level architecture development. This paper describes a parallel effort that focuses more on (a) a robust classification algorithm of progression quality and remedies and (b) vendor-independent distributed implementation architecture for the proposed algorithm. Rather than immediate implementation issues, this research establishes a flexible development framework for theoretical development and experimentation of adaptive control algorithms in the context of closed-loop systems operation.
Near-infrared Periodic and Other Variable Field Stars in the Field of the Cygnus OB7 Star-forming Region

We present a subset of the results of a three season, 124 night, near-infrared monitoring campaign of the dark clouds Lynds 1003 and Lynds 1004 in the Cygnus OB7 star forming region. In this paper, we focus on the field star population. Using three seasons of UKIRT J, H and K band observations spanning 1.5 years, we obtained high-quality photometry on 9,200 stars down to J=17 mag, with photometric uncertainty better than 0.04 mag. After excluding known disk bearing stars we identify 149 variables – 1.6% of the sample. Of these, about 60 are strictly periodic, with periods predominantly < 2 days. We conclude this group is dominated by eclipsing binaries. A few stars have long period signals of between 20 and 60 days. About 25 stars have weak modulated signals, but it was not clear if these were periodic. Some of the stars in this group may be diskless young stellar objects with relatively large variability due to cool star spots. The remaining �60 stars showed variations which appear to be purely stochastic.
Elemental Analysis of Lubricating Grease by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES)

Lubricating grease is a mixture with complex properties that poses far more difficult analytical challenges than do its individual components. At many petroleum testing laboratories, Inductively Coupled Plasma Atomic Emission Spectroscopy, or ICP-AES, is used for the analysis of additive elements and wear metals in oil. However, it may also be used to measure the concentration of both additive metals and contaminants in lubricating grease. However, unlike some of the other matrices that are routinely analyzed, grease cannot be simply diluted for direct sample introduction into the instrument without some form of acid digestion. This paper will discuss how ICP-AES is used as a grease analysis tool. Several sample preparation schemes will be covered, including classical sulfated ash on a hot plate, microwave assisted dry ash, and microwave assisted acid digestion. Comparison data from different digestion techniques will illustrate potential problems that may be encountered by the analyst in each of these methods. The advantages of closed-vessel microwave digestion for the analysis of elements that are often volatilized under normal digestion conditions will be discussed.
Getting Acquainted with the Dandelion

(1980). Getting Acquainted with the Dandelion. Science Activities: Vol. 17, Environmental Education, pp. 20-24.
Poly(alkylene oxide) ionomers. XI. Polymerization and copolymerization of methyl ω-epoxyundecanoate and characterization of the polymers†

Methyl 10-undecenoate was epoxidized in nearly quantitative yield with m-chloroperoxy-benzoic acid to methyl 10,11-epoxyundecanoate. The functional epoxide monomer was polymerized by the reaction product of triethylaluminum/water/acetylacetone (1.0/0.5/1.0) to a high molecular weight elastomer having pendent carboxyl groups, and a molecular weight distribution near the most probable distribution. With the same initiator system, methyl 10,11-epoxyundecanoate was copolymerized with ethylene oxide, propylene oxide, 1-butene oxide, 1-hexene oxide, phenyl glycidyl ether, epichlorohydrin, and 4,4,4-trichloro-1-butene oxide. The copolymers were typically high in molecular weight, elastomeric, and had methyl 10,11-epoxyundecanoate incorporations similar to the initial feed ratio of comonomers. The new family of functional polymers were characterized by their infrared and NMR spectra, dilute solution viscosity and thermal transitions.
Three-dimensional imaging of nociceptive intraepidermal nerve fibers in human skin biopsies.

A punch biopsy of the skin is commonly used to quantify intraepidermal nerve fiber densities (IENFD) for the diagnosis of peripheral polyneuropathy 1,2. At present, it is common practice to collect 3 mm skin biopsies from the distal leg (DL) and the proximal thigh (PT) for the evaluation of length-dependent polyneuropathies 3. However, due to the multidirectional nature of IENFs, it is challenging to examine overlapping nerve structures through the analysis of two-dimensional (2D) imaging. Alternatively, three-dimensional (3D) imaging could provide a better solution for this dilemma. In the current report, we present methods for applying 3D imaging to study painful neuropathy (PN). In order to identify IENFs, skin samples are processed for immunofluorescent analysis of protein gene product 9.5 (PGP), a pan neuronal marker. At present, it is standard practice to diagnose small fiber neuropathies using IENFD determined by PGP immunohistochemistry using brightfield microscopy 4. In the current study, we applied double immunofluorescent analysis to identify total IENFD, using PGP, and nociceptive IENF, through the use of antibodies that recognize tropomyosin-receptor-kinase A (Trk A), the high affinity receptor for nerve growth factor 5. The advantages of co-staining IENF with PGP and Trk A antibodies benefits the study of PN by clearly staining PGP-positive, nociceptive fibers. These fluorescent signals can be quantified to determine nociceptive IENFD and morphological changes of IENF associated with PN. The fluorescent images are acquired by confocal microscopy and processed for 3D analysis. 3D-imaging provides rotational abilities to further analyze morphological changes associated with PN. Taken together, fluorescent co-staining, confocal imaging, and 3D analysis clearly benefit the study of PN.
The Saccharomyces cerevisiae RNA polymerase III recruitment factor subunits Brf1 and Bdp1 impose a strict sequence preference for the downstream half of the TATA box

Association of the TATA-binding protein (TBP) with its cognate site within eukaryotic promoters is key to accurate and efficient transcriptional initiation. To achieve recruitment of Saccharomyces cerevisiae RNA polymerase III, TBP is associated with two additional factors, Brf1 and Bdp1, to form the initiation factor TFIIIB. Previous data have suggested that the structure or dynamics of the TBP-DNA complex may be altered upon entry of Brf1 and Bdp1 into the complex. We show here, using the altered specificity TBP mutant TBPm3 and an iterative in vitro selection assay, that entry of Brf1 and Bdp1 into the complex imposes a strict sequence preference for the downstream half of the TATA box. Notably, the selected sequence (TGTAAATA) is a perfect match to the TATA box of the RNA polymerase III-transcribed U6 small nuclear RNA (SNR6) gene. We suggest that the selected T*A base pair step at the downstream end of the 8 bp TBP site may provide a DNA flexure that promotes TFIIIB-DNA complex formation.
Principal Component Analysis of Diffuse Near-Infrared Reflectance Data from Paper Currency

Product tampering and product counterfeiting are increasing the need for methods to quickly determine product authenticity. One of the concepts that we are investigating for the detection of counterfeit objects involves the use of pattern recognition techniques to analyze multivariant data acquired from properties intrinsic to the object. The near-infrared reflectance spectra of currency and other paper stock were used as a test system. The sample population consisted of authentic currency, circulated and uncirculated, and cotton and rag paper stock as stand-ins for counterfeit currency. Reflectance spectra were obtained from a spot that was essentially void of printing on both sides of the currency specimens. Although the reflectance spectra for all of the samples were very similar, principal component analysis separated the samples into distinct classes without there being any prior knowledge of their chemical or physical properties. Class separation was achieved even for currency bills that differed only in their past environment. Leave-One-Out procedures resulted in 100% correct classification of each member of the sample set. A K-Nearest-Neighbor test or a linear discriminate can be used to correctly classify unknown samples.
Local inverse photoemission with the scanning tunneling microscope

We have placed photon detectors near the tip-sample region of a scanning tunneling microscope (STM). The intensity of the outcoming photons at various energies was measured as a function of bias voltage between tip and sample. Local inverse-photoemission spectra are presented for polycrystalline tantalum, Si(111)7 × 7, and polycrystalline silver, and are compared to conventional inverse photoemission and tunneling spectroscopy. Some apparent differences are discussed in terms of image/field states. In addition (x,y) scans of the photon intensity demonstrate the potential of this novel technique to combine the spectral resolving power of inverse photoemission with the spatial resolving capabilities of STM.
Resonance Raman Scattering by the Green Fluorescent Protein and an Analogue of Its Chromophore

To examine the protonation state and excitation dynamics of green fluorescent protein (GFP), the electronic, resonance Raman, and Fourier transform infrared spectra of GFP were compared to the corresponding spectra of an analogue of the GFP chromophore (4-hydroxybenzylidene-2,3-dimethyl-imidazolinone, HBDI). Spectra were measured with GFP in both H2O and D2O and with HBDI in ordinary or deuterated ethanol under neutral, acidic, or basic conditions. The vibrational transitions were assigned with the aid of ab initio calculations using density functional theory methods. The results indicate that the main absorption band of GFP at 400 nm represents the neutral chromophore and the minor band at 475 nm represents the anion. The resonance Raman spectra of both GFP and neutral HBDI are dominated by a band in the region of 1565 cm-1. We assign this band to the “CN stretch” mode, which involves stretching of the imidazolinone CN bond and the central CC bond of the chromophore. The absence of resonance Raman intens...
Fault-tolerant FIR adaptive filter using the conjugate gradient algorithm

In several recent papers we have introduced the notion of Adaptive Fault Tolerance (AFT), where the adaptive process is used to automatically compensate for faults occurring in the adaptive coefficients. Several adaptive filtering structures have been proposed which use AFT to provide fault tolerance with very low hardware overhead, while maintaining reasonable convergence behavior for certain classes of input signals. The previous structures were adapted with the LMS algorithm which is known to have poor convergence properties when the input signal is highly colored. In this paper we propose using the Conjugate Gradient (CG) algorithm to update the filter coefficients. The CG algorithm, which allows rapid convergence of the fault tolerant adaptive filter regardless of the input noise statistics, is known not to suffer from the same performance drawbacks as the LMS algorithm. Simulations will be presented to demonstrate the performance of the CG algorithm and comparisons with previous work will be made. Implementation issues will also be discussed.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Insect chromatophorotropic factors: The isolation of polypeptides from Periplaneta americana and Apis mellifera with melanophore-dispersing activity in the crustacean, Uca pugilator

Abstract Melanophore-dispersing activity was isolated from head extracts of the orthopteran Periplaneta americana and the hymenopteran Apis mellifera . Partial purification of the P. americana extracts indicated two peaks of activity which were designated PCF-1 and PCF-2. These factors were water-soluble, heat-stable, trypsin-sensitive polypeptides with apparent molecular weights of 3500 and 1000 daltons, respectively. Both factors were distributed throughout the central nervous system of P. americana , but neither factor was detected in the corpora cardiaca-corpora allata complex of this species. Cardiac excitatory activity was found to coelute with the PCF-2 peak on Sephadex G-25 and this activity also was trypsin sensitive. The melanophore-dispersing factor isolated from A. mellifera (ACF) was a 20,000-dalton, water-soluble, methanol-insoluble, trypsin-sensitive, temperature- and oxidation-sensitive polypeptide.
Dispersion of repolarization

Abstract Repolarization duration is highly dependent on heart rate. A major concern when evaluating dispersion of repolarization is the possible influence of heart rate on the magnitude of dispersion. Another consideration relates to a potential relationship between overall duration of repolarization and the magnitude of dispersion, that is, whether patients with longer repolarization duration present with increased or decreased dispersion of repolarization. Therefore, the following relationships were studied in 380 normal subjects, 68 coronary artery disease (CAD) patients, and 41 long QT syndrome (LQTS) patients: the magnitude of dispersion (JTd) versus cycle length (R-R) and dispersion versus repolarization duration (QTc interval). Dispersion of repolarization (JTd), measured as the maximal difference in JT interval duration between precordial leads, was significantly higher in LQTS patients than in normal subjects or CAD patients (120 ± 72 vs 53 ± 42 and 48 ± 22 ms, respectively). In neither normal subjects, CAD patients, or LQTS patients were there significant relationships between the magnitude of dispersion and the R-R interval ( r = .094, .158, and .233, respectively; not significant) and between the magnitude of dispersion and QTc duration ( r = .0443, −.094, and .126, respectively; not significant). In normal subjects, CAD patients, and LQTS patients, the magnitude of dispersion is not significantly related to heart rate, indicating that there is no need for heart rate adjustment of dispersion parameters. In addition, there is no significant association between the magnitude of dispersion and duration of repolarization.
Automatic TCP buffer tuning

With the growth of high performance networking, a single host may have simultaneous connections that vary in bandwidth by as many as six orders of magnitude. We identify requirements for an automatically-tuning TCP to achieve maximum throughput across all connections simultaneously within the resource limits of the sender. Our auto-tuning TCP implementation makes use of several existing technologies and adds dynamically adjusting socket buffers to achieve maximum transfer rates on each connection without manual configuration.Our implementation involved slight modifications to a BSD-based socket interface and TCP stack. With these modifications, we achieved drastic improvements in performance over large bandwidth delay paths compared to the default system configuration, and significant reductions in memory usage compared to hand-tuned connections, allowing servers to support at least twice as many simultaneous connections.
Analysis of the Nuevo León magnetic anomaly and its possible relation to the Cerro Prieto magmatic-hydrothermal system

The broad dipolar magnetic anomaly whose positive peak is centered near Ejido Nuevo Leon, some 5 km east of the Cerro Prieto I Power Plant, has long been suspected to have a genetic relationship to the thermal source of the Cerro Prieto geothermal system. This suspicion was reinforced after several deep geothermal wells, drilled to depths of 3 to 3.5 km over the anomaly, intersected an apparent dike-sill complex consisting mainly of diabase but with minor rhyodacite. A detailed fit of the observed magnetic field to a computer model indicates that the source may be approximated by a tabular block 4 by 6 km in area, 3.7 km in depth, 2.3 km thick, and dipping slightly to the north. Mafic dike chips from one well, NL-1, were analyzed by means of electron microprobe analyses which showed tham to contain a titanomagnetite that is paramagnetic at in-situ temperature conditions. As the dike mineralogy does not account for the magnetic anomaly, the magnetic source is believed to be a deeper, magnetite-rich assemblage of peridotite-gabbro plutons. the suite of igneous rocks was probably passively emplaced at a shallow depth in response to crustal extension and thinning brought on by strike-slip faulting. The bottommore » of the magnetic source body, at an estimated depth of 6 km, is presumed to be at or near that of the Curie isotherm (575/sup 0/C) for magnetite, the principal ferromagnetic mineral in peridotitic-gabbroic rocks. The geological model derived from the magnetic study is generally supported by other geophysical data. In particular, earthquake data suggest dike injection is occurring at depths of 6 to 11 km in an area beneath the magnetic source. Thus, it is possible that heat for the geothermal field is being maintained by continuing crustal extension and magmatic activity.« less
Kenneth Burke's Concept of Entitlement.

The paper explores the ways in which Kenneth Burke's concept of entitlement can be applied to the study of theatre. In so doing, it suggests answers to two critical problems that must arise whenever a Burkeian approach to theatre is attempted: (1) the extent to which Burke's critical system can be applied beyond the realm of verbal language and (2) the distinction, often fuzzy in Burke's own writings, between critical and creative applications of his theory. After an introductory section which sets forth the general functions that Burke ascribes to entitlement, the paper considers each of three different kinds of titles that might be connected with a theatrical (and, hence, a nonverbal) artwork. The critical title is a verbal label, provided by a critic and therefore external to the artwork, that describes unity within the artwork and provides a perspective from which the artwork can be discussed. The artistic title is an element within the artwork itself that sums up a range of emotional factors or ident...
Rapid temporal modulation of synchrony in cortical interneuron networks with synaptic plasticity

The synchrony of neurons in the extrastriate visual cortex is modulated by selective attention even when there are only small changes in firing rate (Fries et al., Science 291 (2001) 1560). We used Hodgkin-Huxley type models of cortical neurons to investigate the mechanism by which the degree of synchrony can be modulated independently of changes in firing rate. The synchrony of local networks of model cortical interneurons interacting through inhibitory synapses with short-term synaptic plasticity was modulated on a fast timescale by selectively activating a fraction of the interneurons. We found that facilitation enhanced the synchrony of the system whereas depression reduced it. In systems with synaptic plasticity, the synchrony modulation was accompanied by larger changes in the firing rate.
Work-family conflict and social undermining behaviour: An examination of PO fit and gender differences

In this study, we develop and test a novel theoretical model that addresses the relationship between work–family conflict (WFC), sex, PO fit perceptions (PO fit) and social undermining behaviour. Drawing on the source attribution perspective and role theory, we hypothesize that WFC is positively associated with social undermining behaviouratalaterpointintimeandthisrelationshipisexplainedinpartbydiminishedPO fit perceptions. Furthermore, we argue that female employees reporting high levels of WFC are more likely to engage in undermining behaviour relative to men when PO fit is consideredasamediatingvariable.Specifically,weassertthatPOfitisdepletedtoalarger extentforfemalethanformaleworkersand,subsequently,isassociatedwithhigherlevels of undermining behaviour. In a sample of over 300 full-time working adults employed acrossavarietyofoccupations,wefoundsupportforeachofourpredictions.Implications for research and practice are addressed. Practitioner points Work–family conflict contributes to co-worker-directed social undermining behaviour because it weakens person–organization fit perceptions – especially among women. Organizational leaders can create a stronger sense of community among employees, offer avenues for support as well as resources that can help workers cope with the difficulties associated with WFC. Leadersimplementing interventions should try tomaintain asense of ‘fit’ andbelongingness within the organization and let workers know they are valued even in the face of high levels of work-related demands and challenges. Work-life balance remains painfully elusive for many workers. A 2010 survey of 1,043 AmericansconductedbytheSocietyforHumanResourcesManagementrevealedthat89% of employees believed that work-life balance was a problem, 54% indicated that it was a significantproblem,and43%didnotfeelthattheiremployerwasdoingenoughtoaddress this issue. These results are notable because when the demands of one’s work role encroach upon one’s family role, defined as work–family conflict (WFC; Kossek & Ozeki, 1998), employees experience career dissatisfaction, burnout, turnover, absenteeism, hostile behaviour at home and physical health, and mental well-being
Multiple-echo proton spectroscopic imaging using time domain parametric spectral analysis

A multiple-echo MR spectroscopic imaging (MRSI) method is presented that enables improved metabolite imaging in the presence of local field inhomogeneities and measurement of transverse relaxation parameters. Short echo spacing is used to maximize signal energy from inhomogeneously line-broadened resonances, and time domain parametric spectral analysis of the entire echo train is used to obtain sufficient spectral resolution from the shortened sampling periods. Optimal sequence parameters for 1H MRSI are determined by computer simulation, and performance is compared with conventional single-echo acquisition using phantom studies at a field strength of 4.7 T. A preliminary example for use at 1.5 T is also presented using phantom and human brain MRSI studies. This technique is shown to offer improved performance relative to single-echo MRSI for imaging of metabolites with shortened T2* values due to the presence of local field inhomogeneities. Additional advantages are the intrinsic measurement of metabolite T2 values and determination of metabolite integrals without T2 weighting, thereby facilitating quantitative metabolite imaging.
PHOTOPEROXIDATION OF LENS LIPIDS: PREVENTION BY VITAMIN E

— Light of visible frequency was observed to initiate peroxidative degradation of lipids of rat lenses when the latter were maintained in organ culture. The extent of degradation was monitored by measurement of malanaldehyde. This photodegradative process, which we believe is triggered by light catalyzed generation of superoxide and its subsequent transformation to other potent oxidants. was observed to be thwarted substantially if the medium of organ culture was fortified with 10−3 and 107M vitamin E (α-tochopherol). These studies suggest that vitamin E may be metabolically beneficial by protecting light exposed tissues, such as those in the eye against photoperoxidativc damage concomitant to light-catalyzed generation of oxygen-free radicals. The findings appear relevant to age-associated pathogenesisof cataracts and their possible attenuation. In addition, they provide a basis of pathogenesis in other ocular tissues such as the macula known to undergo age-dependent degeneration.
Salivary cortisol concentrations and behavior in a population of healthy dogs hospitalized for elective procedures

Identification of severe stress in hospitalized veterinary patients may improve treatment outcomes and welfare. To assess stress levels, in Study 1, we collected salivary cortisol samples and behavioral parameters in 28 healthy dogs hospitalized prior to elective procedures. Dogs were categorized into two groups; low cortisol (LC) and high cortisol (HC), based on the distribution of cortisol concentrations (< or ≥ 0.6 µg/dL). We constructed a stress research tool (SRT) based on three behaviors, (head resting, panting and lip licking) that were most strongly related to salivary cortisol concentrations. In Study 2, we collected salivary cortisol samples from 39 additional dogs, evaluated behavior/cortisol relationships, assigned each dog to an LC or HC group, and tested the ability of the SRT to predict salivary cortisol. Median (interquartile range) salivary cortisol concentrations were not different between Study 1 (0.43 µg/dL, 0.33 to 1.00 µg/dL) and Study 2 dogs (0.41 µg/dL, 0.28 to 0.52 µg/dL). The median salivary cortisol concentration was significantly lower (P ≤ 0.001) in LC versus HC dogs in each study; (Study 1 LC: 0.38 µg/dL, (0.19 to 0.44), n = 19, HC: 2.0 µg/dL, (1.0 to 2.8), n = 9, and Study 2 LC: 0.35 µg/dL, (0.25 to 0.48), n = 28, HC: 0.89 µg/dL, (0.66 to 1.4), n = 7). In Study 1, three behaviors were found to be associated with salivary cortisol concentrations. Duration of head resting was negatively associated with salivary cortisol (ρ = -0.60, P = 0.001), panting and lip licking were positively associated with cortisol (ρ = 0.39, P = 0.04, and 0.30, P = 0.05, respectively), Head resting (p = 0.001) and panting (p = 0.003) were also associated with LC/HC group assignment. In Study 2 dogs, the three behaviors correlated (but not significantly) with salivary cortisol concentration; of the three, only head resting was significantly associated with LC/HC group assignment (P = 0.03). The SRT derived from Study 1 was effective at prediction of salivary cortisol concentrations when applied to 20 min but not 2 min of behavioral data from Study 2. Additionally, we note that dexmedetomidine and butorphanol sedation more than 6 h prior to measurement was found to be significantly (P = 0.05) associated with lower salivary cortisol concentrations when compared to unsedated dogs. Our work offers support for eventual construction of a rating tool that utilizes the presence or absence of specific behaviors to identify higher salivary cortisol concentrations in dogs subjected to hospitalization, which may be tied to greater psychogenic stress levels. Future work to investigate the effects of stress on dogs and its mitigation in clinical situations may be approached by studying a combination o f parameters, and should consider the possible beneficial effects of sedatives.
Projections of the capacitated network loading problem

Abstract Consider an undirected network and a set of commodities with specified demands between various pairs of nodes of the network. Given two types of capacitated facilities that can be installed (loaded) for arc dependent costs, we have to determine the integer number of facilities to load on each arc in order to send the required flow of all commodities at minimum total cost. We present a natural mixed-integer programming formulation of the problem and then consider its single commodity and multicommodity versions. We develop “equivalent” formulations in a lower-dimensional space by projecting out the flow variables and study the polyhedral properties of the corresponding projection cones. Our results strengthen an existing result for multicommodity flow problems. We also characterize several classes of facet defining inequalities for this lower-dimensional polyhedron, and conclude by identifying some open problems and future research directions.
Single Molecule Fluorescence Imaging at Micromolar Concentrations

The conventional total internal reflection (TIR) microscopy or confocal microscopy renders a detection volume of 20-200 attoliters, limiting single molecule experiments to nanomolar concentrations of fluorescently labeled reagents. However, many biological processes require higher concentrations of proteins or substrates. Here, we present a novel combination of existing techniques with confocal microscope to reduce the detection volume to below 300 zeptoliter, which represents a three orders of magnitude reduction compared to the confocal case. The sub-diffraction focal spot of stimulated emission depletion microscopy accounts for > 20-fold reduction of volume in lateral direction and a simple convex lens provides > 40-fold confinement in axial direction. This method should allow single molecule studies of complex processes that require transient interactions between multiple components.
Gross Physical Anomalies in F1 Progeny of Irradiated and Unirradiated Coho Salmon

Abstract The F1 progeny of irradiated and unirradiated coho sahnon were the object of a study on the occurrence of gross physical anomalies. Experimental lots consisted of 69,000 F1 progeny of coho salmon that had been irradiated during the egg-and-yolk-absorption stage with a 0.1 curie cobalt-60 source at a daily dose of 0.44 roentgens, resulting in a total dose of 40 roentgens. Control lots consisted of 95,500 F1 progeny of unirradiated coho salmon. Anomalies that occurred most commonly in both experimental and control lots were those concerning the operculum, the spinal column, the tail, and the fins. No significant differences were found between experimental and control lots in regard to the occurrence of gross physical anomalies.
Postsynaptic response to stimulation of the Schaffer collaterals with properties similar to those of synaptosomal aspartate release.

Abstract Aspartate satisfies all the criteria normally required for identification of a CNS neurotransmitter. Nevertheless, little electrophysiological evidence supports the existence of aspartate transmission. In studies with rat hippocampal synaptosomes, chemically evoked aspartate release differed from glutamate release in its relative sensitivity to increased Ca2+ concentration outside the presynaptic active zones, inefficient coupling to P/Q-type Ca2+ channels, sensitivity to KB-R7943, and resistance to native Clostridial toxins. We took advantage of these differences to search for a potential aspartate-mediated response at Schaffer collateral synapses in organotypic hippocampal slice cultures. The slice cultures were pretreated with botulinum neurotoxin C (BoNT/C) to eliminate most of the glutamate release so that an expectedly smaller aspartate-like component of the compound EPSC could be detected by whole cell patch clamp recording. In control cultures, NMDA receptor activation accounted for only 18% of the evoked EPSC and an NR2B-selective antagonist reduced the NMDA receptor-mediated component by only 20%. Block of P/Q-type Ca2+ channels essentially eliminated the response and 0.1 μM KB-R7943 had no significant effect. In BoNT/C-pretreated cultures, however, NMDA receptor activation accounted for 77% of the evoked EPSC and an NR2B-selective antagonist reduced the NMDA receptor-mediated component by 57%. Block of P/Q-type Ca2+ channels reduced the response by only 28%, but 0.1 μM KB-R7943 reduced it by 45%. These results suggest that part of the Schaffer collateral synaptic response has pharmacological properties similar to those of synaptosomal aspartate release and may therefore be mediated at least partly by released aspartate.
A Common Binding Site on the Microsomal Triglyceride Transfer Protein for Apolipoprotein B and Protein Disulfide Isomerase

The assembly of triglyceride-rich lipoproteins requires the formation in the endoplasmic reticulum of a complex between apolipoprotein B (apoB), a microsomal triglyceride transfer protein (MTP), and protein disulfide isomerase (PDI). In the MTP complex, the amino-terminal region of MTP (residues 22-303) interacts with the amino-terminal region of apoB (residues 1-264). Here, we report the identification and characterization of a site on apoB between residues 512 and 721, which interacts with residues 517-603 of MTP. PDI binds in close proximity to this apoB binding site on MTP. The proximity of these binding sites on MTP for PDI and amino acids 512-721 of apoB was evident from studies carried out in a yeast two-hybrid system and by co-immunoprecipitation. The expression of PDI with MTP and apoB16 (residues 1-721) in the baculovirus expression system reduced the amount of MTP co-immunoprecipitated with apoB by 73%. The interaction of residues 512-721 of apoB with MTP facilitates lipoprotein production. Mutations of apoB that markedly reduced this interaction also reduced the level of apoB-containing lipoprotein secretion.
Willingness to pay for AIDS treatment: myths and realities.

By AIDS day 2002 HIV/AIDS in Africa had killed 20.4 million and infected 29.4 million people. This number of deaths is seven times that in the Nazi holocaust and it approaches the death toll associated with transatlantic slave trading. Treatment for AIDS includes monitoring of disease progression psychosocial support provision of adequate nutrition teaching healthy living and survival skills prophylaxis and treatment of opportunistic infections and antiretroviral treatment. Such holistic treatment can now be provided at an all-inclusive cost of about US$600 dollars per year. Yet most African countries and donors still judge this amount to be too costly. The cost of not treating a person with AIDS includes the loss of output of each patient; loss of income of care-givers; cost of treatment in homes clinics and hospitals; funeral costs; death and survivor benefits; and the cost of orphan care and support. These costs are met by patients families employers governments and society at large. On economic grounds alone treatment should be provided for all those for whom the present value of expenses exceeds the cost of not giving treatment. Results of several studies show that this situation is now true for many classes of people and workers. The issue has become not whether we can afford to treat but whether we can afford not to. Here I review imagined obstacles and faulty arguments against large-scale treatment programmes and show that unwillingness to pay is the main reason for inaction. (excerpt)
Completion of the Norwalk virus genome sequence

Norwalk virus (NV) is the prototype human calicivirus, and causes epidemic outbreaks of acute gastroenteritis. The sequence and predicted genome organization of NV and a NV-like virus [Southampton virus (SHV)] suggested they are similar viruses at the nucleotide and amino acid level, although SHV was reported to be antigenically distinct from NV. A recent review described the discovery of an additional 12 nucleotides at the 5′ end of SHV and prompted us to investigate the possibility of additional nucleotides at the 5′ end of the NV genome. The results obtained by homopolymeric tailing of NV cDNA with dCTP and dATP showed 12 additional nucleotides also are present on the NV genomic RNA. These data are important with respect to the biology of the virus, and make the genome sequence of NV complete.
Electric service restoration using microgrids

A Microgrid-assisted methodology is proposed in this paper for electric service restoration in distribution networks. Success of restoration algorithms is closely tied with the availability of sufficient capacity on the restoration path(s). When the restoration path is at or near full capacity, some capacity relief may be achieved through the usage of Microgrids. By increasing the generation level of its micro-generators, reducing the demand of its demand responsive loads, or, as the last resort, by islanding from the grid, a Microgrid can help alleviate the congestion on the restoration path, and therefore assist the service restoration algorithm. The methodology put forth in this paper considers a potential restoration circuit equipped with Microgrids, and provides the most cost-effective operational solution while achieving the targeted restoration capacity. Network operational constraints, demand variations, and fluctuations in energy pricing are all taken into account. The problem is formulated as a mixed-integer nonlinear programming problem, and is implemented on a modified version of the IEEE 123-node test distribution system.
Characterization of the quantitative trait locus for haloperidol‐induced catalepsy on distal mouse chromosome 1

We report here the confirmation of the quantitative trait locus for haloperidol-induced catalepsy on distal chromosome (Chr) 1. We determined that this quantitative trait locus was captured in the B6.D2-Mtv7a/Ty congenic mouse strain, whose introgressed genomic interval extends from approximately 169.1 to 191.3 Mb. We then constructed a group of overlapping interval-specific congenic strains to further break up the interval and remapped the locus between 177.5 and 183.4 Mb. We next queried single nucleotide polymorphism (SNP) data sets and identified three genes with nonsynonymous coding SNPs in the quantitative trait locus. We also queried two brain gene expression data sets and found five known genes in this 5.9-Mb interval that are differentially expressed in both whole brain and striatum. Three of the candidate quantitative trait genes were differentially expressed using quantitative real-time polymerase chain reaction analyses. Overall, the current study illustrates how multiple approaches, including congenic fine mapping, SNP analysis and microarray gene expression screens, can be integrated both to reduce the quantitative trait locus interval significantly and to detect promising candidate quantitative trait genes.
Managerial Leadership: A Review of Theory and Research

This article reviews and evaluates major theories of leadership and summarizes findings from empirical research on leadership. Major topics and controversies include leadership versus management, leader traits and skills, leader behavior and activities, leader power and influence, situational determinants of leader behavior, situational moderator variables, transformational leadership, importance of leadership for organizational effectiveness, and leadership as an attributional process. Methodological issues in leadership research and implications for improving managerial practice are discussed also. An integrating conceptual framework is presented to show how the different theories and lines of research fit together.
Duloxetine in the treatment of generalized anxiety disorder

Generalized anxiety disorder (GAD) is a relatively prevalent and disabling condition. Duloxetine, an inhibitor of both serotonin and norepinephrine, was approved by the US FDA in 2007 for the treatment of GAD. Short-term efficacy of duloxetine in dosages of 60-120 mg/day has been established in four double-blind, placebo-controlled trials of 9-10 weeks duration. Duloxetine has also been found to meet rigorous criteria for noninferiority in comparison with venlafaxine in GAD. Duloxetine has shown superiority on measures of functioning and quality of life and, compared with placebo treatment, it reduces painful physical symptoms common in GAD patients. Continuation treatment for acute treatment responders was found to prevent relapse of GAD to a significantly greater degree than placebo. In all acute and long-term trials, duloxetine was well-tolerated. This body of research suggests that duloxetine should be one of the options considered as a first-line treatment for GAD.