cssi/SciSciGPT-SciSciNet huggingface dataset:
The performance of a dual alkali aerosol flame ionization detector for gas chromatography

Abstract The described alkali flame ionization detector (AFID) differs from other designs by introducing the alkali salt into the detector in the form of an aerosol. The preheated, desolvated alkali aerosol salt is introduced into a dual hydrogen gas flame assembly. This detector shows no evidence of fatigue due to the constant delivery of salt into the detector, compared to the fixed alkali supply found in other versions, which can be depleted by vaporization and become easily contaminated. This AFID design also allows for operation as an FID by implementing a simple pneumatic procedure. This paper deals with the performance and optimization of the detector using a dual alkali salt aerosol flame design for organonitrogen and organophosphorus compounds. Detection limits were 23.5 pgN/sec for alachlor, 185 pgN/sec for dinoseb, and 4.83 pgP/sec to 10.1 pgP/sec for various pesticides studied. Selectivity ratios are tunable to 6.6 × 106 gP/gC, 4.0 × 104 gN/gC and 2.3 × 103 gP/gN by establishing the appropriat...
Risk stratifiers for sudden cardiac death (SCD) in the community: primary prevention of SCD

Time for primary review 34 days. There are currently 250,000 sudden cardiac deaths (SCD) in the United States every year constituting approximately 50% of all coronary heart disease (CHD) deaths [1]. Despite the decline in CHD mortality over the last decade, little proportionate change has been seen in the characteristics of CHD deaths. The majority of deaths are still sudden, occurring out-of-hospital and in the emergency room [2,3]. SCD is the most common cause of ischemic heart disease death in adults under the age of 65 years [2,3] and, therefore, is a major public health problem in the US and other industrialized countries [4,5]. Despite improved cardiopulmonary resuscitation, survival to hospital discharge is only 3–6% in unselected cases in major metropolitan centers. Even in cities with advanced EMS systems, such as in Seattle, USA, survival to hospital discharge still approaches only 30% among VF arrest victims, and is much lower for other types of cardiac arrest [6,7]. These percentages do not include those arrests that are not witnessed and for which resuscitation is not attempted. Undoubtedly, this percentage will improve with an increase in deployment of automated external defibrillators and public access defibrillation, however, it is clear from these statistics that any substantial reduction in SCD incidence will require effective preventive interventions. In order to prevent SCD, we must be able to predict its occurrence. At this time, the presence and severity of underlying heart disease is the single most highly predictive risk factor for the future occurrence of SCD. The presence of overt CHD and/or CHF markedly increases the risk of SCD [8]. In the Framingham Study, pre-existing CHD was associated with a 2.8–5.3-fold increase in the risk of SCD and CHF was associated with a 2.6–6.2-fold increased risk [4]. Left ventricular dysfunction, … * Corresponding author. Tel.: +1-617-732-8784; fax: +1-617-731-3843
Evaluating the role of distinctiveness in the generation effect

According to the distinctiveness interpretation, generating words from word fragments leads to more distinctive memory traces than reading intact words. As a test of this hypothesis, the generation effect was experimentally compared to three phenomena previously attributed to distinctiveness. Experiments 1 and 2 proved that the generation effect was unlike conceptual and encoding task distinctiveness. In Experiment 3 the generation effect and the effects of orthographic distinctiveness were compared. These two manipulations had similar effects on memory, but the effects were additive—challenging the hypothesis that the generation effect is a result of the unusual appearance of to-be-generated items. Thus, the generation effect is inconsistent with current theories of distinctiveness. The results were consistent with the hypothesis that generated items receive more encoding resources than read items, and that increased attention to generated items may be at the expense of attention to intact items in the list.
Nucleotide sequence and deduced amino acid sequence of Escherichia coli adenine phosphoribosyl-transferase and comparison with other analogous enzymes

Abstract The Escherichia coliapt gene has been analyzed and its nucleotide (nt) sequence and the deduced amino acid (aa) sequence compared to those of other phosphoribosyltransferases (PRTs). The apt mRNA has a 102-nt leader sequence which may form alternate secondary structures. The RNA transcript may also form several 3' hairpin structures, which, however, do not appear to act as Rho-independent terminators. All PRTs, including E. coli adenine PRT (APRT), have a strongly conserved 13-aa sequence, as well as other regions of aa sequence or structural similarity. E. coli APRT is remarkably similar to the mouse enzyme.
Anderson localization of surface electromagnetic waves on rough, perfectly conducting surfaces that are periodic on average

Abstract Based on the integral equation satisfied by the Green's function G ( r o , r ) for electromagnetic waves on a one-dimensional, randomly rough, perfectly conducting surface that is periodic on average, a numerical simulation approach is developed that yields the function 〈| G ( r 0 , r )| 2 〉 − |〈 G ( r 0 , r )〉| 2 , where the angle brackets den the ensemble of realizations of the surface profile function. The frequency dependence of the localization length, obtained from the exponential decay of this function, is then calculated for frequencies about the edges of the surface electromagnetic wave bands of the underlying periodic system. In the gap, the localization length is very small and fairly independent of the frequency. However, when the frequency enters in the allowed bands, the localization length becomes larger; this increase is found to be steeper the weaker the disorder is.
Colossal magnetotransport phenomena due to phase competition in Pr1−x(CaySr1−y)xMnO3 single crystals

Abstract We present a magnetotransport investigation of single crystal Pr0.65(Ca0.75Sr0.25)0.35MnO3, a manganite system specifically tailored to result in a close competition between ferromagnetic metallic and charge ordered antiferromagnetic insulating phases. Below 165 K these phases coexist spatially, with application of a magnetic field favoring the ferromagnetic metallic phase, leading to a magnetoresistance ratio of>1010 in a 2 T magnetic field. Isothermal resistivity vs. field measurements reveal some previously unobserved features accompanying the insulator to metal transition. In addition to unexpected fine structure that occurs as the ferromagnetic metallic phase grows to engulf the entire sample, we observe an intriguing “overshoot” phenomenon in both temperature and field-driven insulator–metal transitions. The resistivity is found to reach a sharp minimum (lower even than the pure ferromagnetic metallic phase) close to the point where the metallic phase percolates. These features are explored in detail and we discuss possible explanations of the effects in terms of pinning of the spatial boundary between the magnetic phases, and the unusual transport effects that could occur when the current flows through a barely percolated path.
Teacher Power--Revisited.

The author reviews four factors that contribute to the reduction of the authority and power of teachers: the Far Right, the Christian Right, the standards movement, and the decline in the use of collective bargaining. As a result of these initiatives, teachers are forced to abandon many progressive educational practices and embrace educational philosophies alien to them; stand by while useful courses such as music, art, physical education, and creative writing are eliminated; adopt drill and grill activities rather than open-ended discussion with students; and forsake any sense of a unique individual school identity and philosophy. Therefore, teaching is fast becoming an unattractive, if not demeaning, profession.
A case from the department of neurology.

Uncompleted suicide attempts are a significant cause of morbidity, which in catastrophic cases can be both medically and ethically challenging to manage. We discuss the case of a 63-year-old man who survived a suicide attempt by venlafaxine (Effexor) overdose, causing an intracranial hemorrhage and leaving him in an apparently awake but noncommunicative state. Ethical concerns arose when considering if he should be indefinitely maintained on life support. These include the difficulties of characterizing his level of consciousness and prognosis; establishing his decisional capacity regarding end-of-life decisions in a setting of depression and suicidality; and assessing the suitability of a surrogate decision-maker. In conclusion, we discuss whether the fact that his grave neurological condition was caused by a suicide attempt was relevant to the decision to continue or withdraw life support. Language: en
Cost-Efficient State Estimation for Precision Projectiles

Guided projectiles are being developed by the Army to precisely eliminate targets and decrease collateral damage. In order to guide to target, precision projectiles must know their position and velocity, i.e. estimate their state. These states are often provided by the Global Positioning System (GPS). However, GPS can be jammed or suffer obstruction in urban or mountainous terrain. Alternate estimation techniques have been developed using an inertial navigation system (INS), but the accuracy requirements of the inertial measurement unit (IMU) in a traditional INS can cause the precision projectile to be orders of magnitude more expensive than unguided projectiles. The novel approach described in this work reduces state estimation cost and enables the projectile to guide to target in a GPSdenied environment. This is achieved by using an extended Kalman filter (EKF) to combine an inexpensive IMU with a computationally efficient point mass (PM) dynamic model. This Army-developed effort will provide cost-effective state estimation to allow precision projectiles to guide to target in a GPS-denied environment. Nomenclature
Determining concepts by group membership

One contribution of this paper is an efficient algorithm for deciding membership in a subgroupH of an Abelian groupG whenG andH are in a special form. Our approach is particularly fast because calculations are postponed until needed, and because some decisions can be made based on the existence of certain objects without actually calculating them. This mathematical problem arises naturally in machine learning, and is particularly relevant to concept modeling. We use genetic algorithms as a nontrivial example of how concept formation may correspond to subgroup formation and to illustrate that analysis may reveal abstract concepts determined by group membership which are not initially apparent. This example forms another contribution of this paper; genetic search has not previously been framed within an algebraic context.
Emergency percutaneous transtracheal ventilation (PTV)

Ventilation through a percutaneous needle catheter inserted into the trachea has been advocated for resuscitation in acute upper airway obstruction. However, the customized, prefabricated equipment proposed by others for that use is not always available. We describe a device for percutaneous transtracheal ventilation (PTV) that can be rapidly assembled using available, inexpensive hospital supplies. With this device, moderate inflation pressures and flow rates of oxygen resulted in arterial PaO2 of greater than 300 torr and PaCO2 values of approximately 40 torr in dogs. PTV may be used as a life-saving measure in cases of acute upper airway obstruction when conventional airway management is unsuccessful.
Reversal of fortune for nascent proteins.

The demonstration of a way in which cytomegalovirus can evade immune surveillance also points to a mechanism by which abnormal proteins, once synthesized, can be degraded.
Juliane Fürst, Stalin's Last Generation: Soviet Post-War Youth and the Emergence of Mature Socialism

Juliane Furst, Stalin's Last Generation: Soviet Post-War Youth and the Emergence of Mature Socialism. Oxford & New York: Oxford University Press, 2010, xiv + 392pp., £60.00 h/b. Recognising the cru...
Two-step phase transformation of anatase to rutile in aqueous suspension

Kinetic data tracking the anatase to rutile phase transformation under acidic, hydrothermal conditions (200 °C, pH 1) are consistent with a two-step transformation mechanism. Fitting the experimental data using phase transformation models, interface–nucleation dominates the early stages of transformation and dissolution–precipitation dominates at later stages. During the first stage, the rate of transformation by interface–nucleation is consistent with a substantially higher number of nucleation sites, possibly generated via crystal growth by oriented aggregation. Characterization of the hydrothermally treated samples using HRTEM revealed that anatase crystal morphologies indicative of crystal growth by oriented aggregation are common. Furthermore, twinned rutile crystals, which are consistent with transformation of anatase twinned across the {112} to rutile twins by interface–nucleation, were also observed. At later stages, the kinetics of the anatase to rutile transformation are consistent with dissolution–precipitation, and the number concentration of rutile crystallites reaches a plateau. These results are consistent with a decrease in crystal growth by oriented aggregation as the anatase particle size increases and the dissolution of anatase and reprecipitation onto already existing rutile crystals due to the larger bulk energy and comparatively small size of anatase.
Diagnostic and prognostic utility of flow cytometric DNA measurements in follicular thyroid tumors.

Distinguishing cellular follicular adenomas (FA) from minimally invasive follicular carcinomas (FC) continues to plague even experienced thyroid pathologists. DNA ploidy analysis has been promoted as a means of making this differentiation; however, the finding of DNA aneuploidy in FA has caused concern that they may demonstrate potential for malignant behavior or should even be reclassified as low-grade noninvasive cancers. In histologically-proven FC, nuclear DNA content has been claimed to have predictive power equivalent to that of all other prognostic factors combined. The aims of the present study, therefore, were to define the DNA ploidy characteristics of FA and FC, to assess the diagnostic potential of cell-cycle parameters, and, in FC, to investigate the prognostic role of such measurements. We measured DNA content of 124 tumors (60 FA, 64 FC). DNA pattern was normal (diploid) in 75% of FA and 45% of FC, tetraploid/polyploid (T/P) in 13% of FA and 25% of FC, and aneuploid in 12% of FA and 30% of FC. FC was histologically verified in 39% of DNA normal, 67% of T/P, and 73% of aneuploid tumors. DNA index, S-phase, G2M, and S-phase plus G2M were analyzed and were not helpful in differentiating between FA and FC. No patient with FA developed tumor recurrence. In FC (excluding the Hurthle cell variant), no significant differences were found among the 3 DNA ploidy groups with respect to either cancer death or tumor recurrence; however, combining the Hurthle cell variant of follicular carcinomas with pure follicular carcinomas, the presence of distant metastases, DNA aneuploidy, and patient age were the only independently significant prognostic variables. Based on these data, while not valuable for determining the presence of malignancy, DNA ploidy determination is of major prognostic value in follicular carcinomas (including the Hurthle cell variant).
Studies on the temperature dependence of methyl anthroate fluorescence

Abstract The temperature dependence of the fluorescence quantum hield φf of methyl-1-, methyl-2- and methyl-9-anthroate was investigated. For the former two esters, the trend of φf versus temperature is consistent with the mechanism proposed earlier to account for the temperature dependence of φf for meso-substituted anthracene. In this mechanism, an activated intersystem crossing to a nearby upper triplet is the only significant non-radiative decay mode. The activation energy EA for fluorescence is a measure of the gap between the emitting singlet S1 and the accepting triplet. Since the former state is more solvent dependent, solvents which lower the S1 energy increase EA and thereby increase φf. Thus EA and φf are inversely related to the S1 energy and directly related to each other. The situation for methyl-9-anthroate is quite different from that of the other esters. While EA is inversely related to the S1 energy, φf is not, and hence there is no correlation between EA and φf. It appears that the φf of methyl-9-anthroate is more dependent on the nature of the solvent than on the measured EA in that solvent. The inclusion of a temperature-independent non-radiative decay mode in the analysis does not produce results consistent with the above mechanism. It is suggested that the difference in behavior for these esters may in some way be related to an excited state geometry change which occurs for methyl-9-anthroate but not for the other two compounds.
Unsteady three-dimensional sources for a two-layer fluid of finite depth and their applications

To our friend Ernie Tuck, in celebration of his multi-faceted talents. The velocity potentials of various unsteady point sources are derived in this paper for a two-layer fluid of finite depth. Two-layer fluids are often used to study effects of density stratification on hydrodynamics of marine systems. The sources here are restricted to the upper fluid layer and the potentials of the induced flows are given for the whole fluid domain. The velocity potentials of a transient source of arbitrary strength and in arbitrary three-dimensional motion are derived first. The potentials of a time-harmonic source without forward speed, and then with forward speed, are obtained from the transient source by specifying the appropriate source strength and motion. These potentials are fundamental to the analyses of various types of body motion in finite water depths under the influence of surface and interfacial waves. As a sample application, a numerical solution of the radiation and diffraction problem for a floating rectangular barge is presented. The results indicate that internal waves can have a strong effect on the motions of the floating barge over a wide range of incident-wave frequencies.
Preclinical Biologic Assessment of Proton Beam Relative Biologic Effectiveness at Proton Therapy Center Houston

The clinical use of protons for the treatment of cancer is one of the most technologically advanced forms of therapy. The newly commissioned M.D. Anderson Cancer Center, Proton Therapy Center Houston is one of the newest facilities offering a complete range of advanced proton therapies designed specifically to minimize treatment-related normal tissue toxicity. As an integral part of the clinical commissioning of this proton beam, we performed an in vivo assessment of the relative biologic effectiveness of the 250-MeV protons relative to standard cobalt 60 using the jejunal crypt microcolony assay in mice. Our data are consistent with a generic relative biologic effectiveness of 1.1, and this relative biologic effectiveness is in agreement with that used to describe most other clinical proton therapy beams worldwide.
Does offshoring create value for shareholders

Abstract We study the wealth effect of offshoring by analyzing the announcement-period returns as well as the long-run operating and stock return performance of firms that offshored their activities in the period 2000–2005. Announcement-period stock returns are positive for firms that offshore activities primarily to reduce costs but are negative for firms that offshore activities for other reasons. Also, announcement-period stock returns are higher for firms with a larger size, better operating performance, lower growth potential, and a higher cost of goods sold in the year prior to the offshoring announcement. Firms that offshore activities primarily to reduce costs enjoy improved operating and stock return performance in the years following the offshoring. Overall, our findings indicate that not all firms enjoy the benefits of offshoring; rather, only those that offshore primarily to reduce costs do.
Normal brain F-18 FDG-PET and MRI anatomy

Image registration techniques will become increasingly important in correlative multimodality imaging. In the case of PET, a structural imaging study can be invaluable in correlating structure metabolism relationships. A registered brain atlas of PET and MRI has been developed by the authors that allows clinicians, residents, fellows, and others to refer to a structural abnormality on MRI or metabolic abnormality on PET and correlate it neuro-anatomically.
Abstract A35: Aligned collagen is a prognostic signature for survival in human breast carcinoma

Evidence for the potent influence of stromal organization and function on invasion and metastasis of breast tumors is ever growing. Here we have performed a rigorous examination of the relationship of a tumor-associated collagen signature (TACS-3), to the long term survival rate of human patients diagnosed with invasive breast cancer. TACS-3 is characterized by bundles of straightened and aligned collagen fibers that are oriented perpendicular to the tumor boundary. An evaluation of TACS-3 was performed in biopsied tissue sections from 196 patients by second harmonic generation (SHG) imaging of the backscattered signal generated by collagen. Univariate analysis of a Cox proportional hazard model demonstrated that the presence of TACS-3 was associated with poor disease-specific and disease free survival, resulting in hazard ratios between 3.0-3.9. Furthermore, TACS-3 was confirmed to be an independent prognostic indicator regardless of tumor grade and size, ER or PR status, HER-2 status, node status, and tumor subtype. Interestingly, TACS-3 was positively correlated to expression of stromal syndecan-1, a receptor for several extracellular matrix proteins including collagens. Ongoing research is currently investigating both the biochemical signaling pathways that give rise to the TACS-3 phenotype as well as the extent of the influence the mechanical properties of an aligned matrix have on invasion. Because of the strong statistical evidence for poor survival in patients with TACS, and since the assessment can be performed in routine histopathologic samples imaged via SHG or using picrosirius, we propose that quantifying collagen alignment is a viable, novel paradigm for the prediction of human breast cancer survival. Citation Format: Matthew W. Conklin, Jens Eickhoff, Kristin Riching, Carolyn Pehlke, Kevin Eliceiri, Paolo Provenzano, Andreas Friedl, Patricia J. Keely. Aligned collagen is a prognostic signature for survival in human breast carcinoma. [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 A35.
A New Electric Hoist Drive for Cranes

Anew system of electric hoist drive has been developed, and its success has been demonstrated in practical use. For the types of hoist for which it is particularly intended this system provides a closer approach to the ideal characteristics than has previously been available. Although the system is not intended for use in all of the important types of hoist, it is expected that further experience and additional study of details and refinements will broaden its field of application beyond that which has, to date, been established in practice.
Low noise field-effect transistor for integrated strain sensing in microelectromechanical systems at 77 K

Abstract We have fabricated a strain-sensing field-effect transistor (FET) from a GaAs/AlGaAs heterostructure containint a near surface two-dimensional electron gas. At 77 K the FET shows a typical transconductance of 30 μS and small signal drain-source resistance of 30 MO. The charge noise has a flat spectrum at high frequencies with magnitude 0.7eHz−1/2and a 1/fnoise corner of approximately 1 kHz. The strain response, due to the piezoelectric effect, shows a noise limited strain sensitivity
Improvement of flexor tendon reconstruction with carbodiimide-derivatized hyaluronic acid and gelatin-modified intrasynovial allografts: study of a primary repair failure model.

Background: Tendon grafts play an important role in flexor tendon reconstruction. This study was an investigation of the effects of surface modification of allograft intrasynovial tendons with carbodiimide-derivatized hyaluronic acid and gelatin in an in vivo canine model. To mimic the actual clinical situation, a novel and clinically relevant model of a failed primary flexor tendon repair was used to evaluate the flexor tendon grafts. Methods: Twenty-eight flexor digitorum profundus tendons from the second and fifth digits of fourteen dogs were lacerated and repaired in zone II in a first-surgery phase. The dogs were allowed free active motion postoperatively. In a second phase, six weeks later, the tendons were reconstructed with use of a flexor digitorum profundus allograft. In each dog, one graft was treated with carbodiimide-derivatized hyaluronic acid and gelatin (the CHG group) and the other was treated with saline solution, as a control. The dogs were restricted from free active motion, but daily therapy was performed beginning on postoperative day 5 and continued until six weeks after the operation, when the animals were killed. The outcomes were evaluated on the basis of digit work of flexion, gliding resistance, healing at the distal attachment, graft cell viability, histological findings, and findings on scanning electron microscopy. Results: In the first phase, all twenty-eight repaired tendons ruptured, with scar and adhesion formation in the repair site. Six weeks after allograft reconstruction, the mean work of flexion was 0.37 and 0.94 N-mm/degree in the CHG group and the saline-solution control group, respectively; these values were significantly different (p < 0.05). The gliding resistance in the CHG group was also significantly less than that in the saline-solution control group (0.18 versus 0.28 N) (p < 0.05), but no difference between groups was observed with regard to the distal tendon-bone pullout strength. Histological analysis showed that tenocytes in the host tendon proliferated and migrated toward the acellular allograft. Conclusions: This primary repair failure model was reproducible and reliable, with a uniform failure pattern, and provides an appropriate and clinically relevant animal model with which to study flexor tendon reconstruction. The surface modification of allografts with carbodiimide-derivatized hyaluronic acid and gelatin improved digital function and tendon gliding ability.
Designing tooth preparations for optimal success

The form of prepared teeth and the amount of tooth structure remove dare important contributors to the mechanical, biologic,and esthetic success of the overlying crown or fixed partial denture.Therefore, it is important to develop clinical guidelines that can be used to optimize success in fixed prosthodontics.
Acoustic crosswell imaging using asymptotic waveforms

Seismic waveforms are inverted using an asymptotic method. The asymptotic method models amplitudes correctly at the caustics and takes nonstationary raypaths into account when computing the waveforms, and thus is an extension of geometrical ray theory. Using numerical differencing, partial derivatives of the data with respect to the model are computed. As expected, these partial derivatives (or sensitivity functions) are concentrated along, but not confined to, raypaths. The sensitivity functions enable the formulation of a waveform inversion algorithm, which is applied to a synthetic crosswell experiment and a laboratory crosswell experiment. The synthetic experiment shows the advantages of the waveform inversion method over conventional traveltime inversion methods. Boundaries of anomalies are better defined, and smearing is reduced. The waveform inversion produces a much lower misfit than the traveltime inversion. The goal of the laboratory experiment was the detection of a nonaqueous phase liquid (NAPL) in water saturated sand. The sand was imaged before and after injection of the NAPL. Using the waveform inversion method, low-velocity anomalies were imaged that correlate well with post-experiment determination of NAPL concentrations. The low-velocity anomaly defocuses the seismic energy. However, the amplitude reduction due to the low-velocity anomaly is not enough to explain the observed low amplitudes. We suggest that other mechanisms (such as multiple scattering, 3-D effects, or intrinsic attenuation) not included in the asymptotic waveform modeling play an important role in decreasing the amplitude.
An experimental study of the relationship between rheological properties and spinnability in the dry spinning of cellulose acetate–acetone solutions

The elastic and viscous properties of five cellulose acetate–acetone solutions, varying from 19.9% to 28.6% solids concentration, are independently determined at 60°C by capillary rheometry techniques. The viscous flow behavior of the solutions is determined over four decades of shear rate. The Bagley analysis is used to determine the entrance pressure drop and the true shear stress at various shear rates. A plot of the entrance pressure drop at the maximum experimental shear rate versus solution concentration undergoes a rapid increase in slope at 24.0% solids concentration, the significance of which is discussed with respect to the development of an elastically deformable chain entanglement network. The die swell behavior of the solutions at 60°C is determined on a commercial-type dry-spinning apparatus. When the die swell ratio is plotted versus volumetric flow rate, all five solutions are found to possess a characteristic curve with a distinct maximum. Photographs illustrating the variation of die swell with volumetric flow rate are shown. Die swell measurements are also shown to correlate well with entrance pressure drop measurements. The degree of spinnability of each cellulose acetate–acetone solution at 60°C is found by determining first godet speed at which one or more threads break abruptly. Spinnability is found to go through a maximum at 24.0% solids concentration. The rheological measurements and spinnability results are discussed through the aid of a single rheological parameter incorporating both elastic and viscous solution responses.
Investigation of pictorial image attributes in descriptive tasks

With the rapid expansion in imaging technologies, retrieval of images from digital collections is a subject of major interest. However, the large amount of research devoted to understanding mechanisms and products of human visual perception has, by and large, not produced information which is directly applicable to the problems of image retrieval, and systems designers still need basic data concerning which image attributes are most typically noticed by humans when viewing images. The goal of this research was to fill this gap in our knowledge, by investigating attributes reported by participants in several describing tasks with pictorial images. Content analysis of word and phrase data revealed forty-two image attributes and ten higher level classes of attributes. Participants most typically describe the perceptual attributes such as the literal object content of images and the human form, as well as the attribute of color. Location appears to be important and needs to be accounted for, as does a group of interpretive attributes labeled CONTENT/STORY. The research results suggest that term variability in the image descriptions is less than previous research might indicate, and communicative constraints operating on visually perceived data may aid in simplifying some of the approaches necessary to accomplish automated indexing. The initial analysis suggests several conceptual frameworks, such as basic level objects, figure-ground, and the use of schemas, as fruitful approaches to image indexing and retrieval.
A summary and evaluation of recent development on harmonic mitigation techniques useful to adjustable speed drives

The authors examine harmonics in three main power areas: the harmonic source, the harmonic effects on power components, and the mitigation techniques used to reduce the amplitude of such harmonics. They cover briefly background information on the first two areas by focusing on electronic motor drives, specifically adjustable speed drives since there are an estimated 400000 units online in the United States, which translates into a large harmonic penetration level. Further summarized are some of the harmonic effects on power system components. A summary and evaluation of developments on harmonic mitigation techniques (HMTs) that have been introduced in the past four years are presented. A classification for all of these HMTs is provided, along with several other facts related to this topic. >
Confirmatory factor analysis of DSM‐IV borderline, schizotypal, avoidant and obsessive‐compulsive personality disorders: findings from the Collaborative Longitudinal Personality Disorders Study

Objective: To test the diagnostic constructs implied by DSM-IV Axis-II personality disorders by examining relationships between different combinations of DSM-IV criteria. Method: Confirmatory factor analysis was used to test the borderline, schizotypal, avoidant and obsessive-compulsive personality disorder constructs in a large treatment-seeking sample (N=668) from a multisite study. A model based on the three DSM-IV Axis II clusters was also tested. Both models were tested against a unitary ‘generic’ model constructed from four criteria sets combined. Results: Goodness-of-fit for both the three-cluster and four disorder models was significantly better than the unidimensional model, and the four-disorder model was significantly better than the three-cluster model. Results were replicated using data from 2-year follow-up obtained by interviewers blind to original Axis II diagnoses at baseline. Conclusion: Support is provided for the DSM-IV disorder-level classification for schizotypal, borderline, avoidant and obsessive-compulsive personality disorders in a treatment-seeking sample.
Diversity training in a sport management class: the effects of different frames on students' attitudes towards organisational diversity

This study drew upon the framing literature to design and test two differently framed diversity modules for effects on students' attitudes towards organisational diversity. Two classes of masters degree students (N = 27 and N = 25) at a Midwestern university served as subjects in the experimental study. Results indicated that both modules positively influenced students' attitudes towards organisational diversity. However, students exposed to the diversity as a competitive advantage frame had significantly higher mean scores regarding diversity in organisations than those exposed to the social justice frame. Results are discussed relative to social identity theory as well as a more critical perspective regarding the dominant pedagogies of US universities.
Housing Market Interventions and Mobility: An International Comparison

Government interventions in housing markets usually have a strong side effect of lowering residential mobility. Interventions tend to raise the price of owner-occupied dwellings and to lower rents compared with household incomes. An index of these two tendencies is calculated for major conurbations of 16 countries. Among these, Switzerland, South Korea, Sri Lanka and the former German Democratic Republic are of particular interest. The rank order correlation of the index with residential mobility appears to be strong, 0.962, and with an elasticity of -0.815 three-quarters of the variance is explained. No correlation was found with the home-ownership rate. In so far as lower mobility impairs housing welfare, market interventions should be avoided, but it is recognised that such interventions primarily reflect concern for equity and externalities.
Early Receptor Potential Measurements in Human Ocular Siderosis

• There is electrophysiologic evidence that photoreceptors have normal visual pigment density (outer segment length) at a stage of ocular siderosis when the photoreceptor membrane function is defective. The early receptor potentials (ERPs) from two patients showed normal amplitudes, although the electroretinograms (ERGs) had reduced a- and b-waves for both cone and rod ERG responses. Since the ERP is generated by photolysis of visual pigment and requires orientation of the pigment molecules by outer segment disc membranes, the normal ERP amplitudes suggest that the photoreceptor outer segments have normal photopigment density, are of normal length, and are properly oriented. However, the transduction mechanism that converts visual pigment photolysis into membrane electrical potentials (the ERG a wave) is defective at this stage of ocular siderosis.
The Smooth Muscle Myosin Seven Amino Acid Heavy Chain Insert's Kinetic Role in the Crossbridge Cycle for Mouse Bladder

The seven amino acid insert in the smooth muscle myosin heavy chain is thought to regulate the kinetics of contraction, contributing to the differences between fast and slow smooth muscle. The effects of this insert on force and stiffness were determined in bladder tissue of a transgenic mouse line expressing the insert SMB at one of three levels: an SMB wild type (+/+), an SMA homozygous type (−/−) and a heterozygous type (+/−). For skinned muscle, an increase in MgADP or inorganic phosphate (Pi) should shift the distribution of crossbridges in the actomyosin ATPase (AMATPase) to increase the relative population of the crossbridge state prior to ADP release and Pi release, respectively. Exogenous ADP increased force and stiffness in a manner consistent with increasing the Ca2+ concentration in both the +/+ and +/− mouse types. However, the −/− type showed a significantly greater increase in force than in stiffness suggesting that immediately prior to ADP release, the AMATPase either has an additional force producing isomerization state or a slower ADP dissociation rate for the −/− type compared to the +/+ or +/− types. Exogenous Pi led to a significantly greater decrease in stiffness than in force for all three mouse types suggesting that there is a force producing state prior to Pi release. In addition, the increase in Pi showed similar changes in the +/+ and −/− types whereas in the +/− type the decreases in both force and stiffness were greater than the other two mouse types indicating that the insert can affect the cooperativity between myosin heads. In conclusion, the seven amino acid insert modulates the kinetics and/or states of the AMATPase, which could lead to differences in the kinetics of contraction between fast and slow smooth muscle.
Mitochondrial Glycerol Phosphate Acyltransferase Contains Two Transmembrane Domains with the Active Site in the N-terminal Domain Facing the Cytosol *

The topography of mitochondrial glycerol-3-phosphate acyltransferase (GPAT) was determined using rat liver mitochondria and mutagenized recombinant rat GPAT (828 aa (amino acids)) expressed in CHO cells. Hydrophobicity analysis of GPAT predicts two transmembrane domains (TMDs), residues 472–493 and 576–592. Residues 224–323 correspond to the active site of the enzyme, which is believed to lie on the cytosolic face of the outer mitochondrial membrane. Protease treatment of rat liver mitochondria revealed that GPAT has a membrane-protected segment of 14 kDa that could correspond to the mass of the two predicted TMDs plus a loop between aa 494 and 575. Recombinant GPAT constructs containing tagged epitopes were transiently expressed in Chinese hamster ovary cells and immunolocalized. Both the C and N termini epitope tags could be detected after selective permeabilization of only the plasma membrane, indicating that both termini face the cytosol. A 6–8-fold increase in GPAT-specific activity in the transfected cells confirmed correct protein folding and orientation. When the C terminus and loop-tagged GPAT construct was immunoassayed, the epitope at the C terminus could be detected when the plasma membrane was permeabilized, but loop-epitope accessibility required disruption of the outer mitochondrial membrane. Similar results were observed when GPAT was truncated before the second TMD, again consistent with an orientation in which the loop faces the mitochondrial intermembrane space. Although protease digestion of the HA-tagged loop resulted in preservation of a 14-kDa fragment, consistent with a membrane protected loop domain, neither the truncated nor loop-tagged enzymes conferred GPAT activity when overexpressed, suggesting that the loop plays a critical structural or regulatory role for GPAT function. Based on these data, we propose a GPAT topography model with two transmembrane domains in which both the N (aa 1–471) and C (aa 593–end) termini face the cytosol and a single loop (aa 494–575) faces the intermembrane space.
Bias analysis of the MUSIC location estimator

The authors present a rigorous bias analysis of the MUSIC location estimator, and they derive an accurate and concise bias expression. The analysis is based on the second-order Taylor series expansion of the derivative of the null spectrum, properties of the null spectrum, and statistics of the estimated signal eigenvectors. It is proven that in the derivation the remainder term in the second-order Taylor series can be dropped but the second-order terms cannot be. Simulations verify that the bias expression is valid over a wide range of signal-to-noise ratios (SNRs) extending down into the resolution threshold region of MUSIC. Although asymptotic, this expression can be accurately applied to a limited number of snapshot cases. The utility of the expression is shown by using it in a study of MUSIC location estimator characteristics. Estimate bias and standard deviation are compared for variations in SNR, numbers of sensors and snapshots, and source correlation. MUSIC resolvability and estimator performance bounds are addressed, accounting for bias. >
CT colonography (virtual colonoscopy) for primary colorectal screening: challenges facing clinical implementation.

Computed tomographic colonography (CTC), also referred to as virtual colonoscopy, is a minimally invasive test for the detection of colorectal polyps. Although its initial performance characteristics for evaluating lowprevalence populations were rather disappointing [1, 2], a larger multicenter trial in asymptomatic adults subsequently showed that CTC has the potential to be an effective primary screening tool [3]. Key features in the latter study that help explain this improved performance include the use of the three-dimensional endoluminal display for primary polyp detection, oral contrast for tagging of residual fluid and stool, segmental unblinding of CTC results at optical colonoscopy (OC), and use of only multidetector CT scanners [3]. As we await further validation of this rapidly evolving technique, actual clinical implementation of primary CTC screening should proceed without delay by those who are currently able to achieve an acceptable accuracy. The need for immediate action is self-evident, as far too many people are dying from a disease that could have been prevented by effective routine screening in more than 95% of cases [4]. There are many important challenges that are likely to be encountered as CTC screening transitions from the realm of research to daily clinical practice (Table 1). This update focuses primarily on three specific issues: (a) development of a logical diagnostic algorithm for CTC screening, (b) identifying the most appropriate group of patients to be screened by CTC, and (c) establishing a mutually beneficial working relationship with gastroenterology. Additional challenges and issues that are also important but are not covered in report include demonstrating the relative cost effectiveness of CTC screening, reimbursement by third-party payers, dedicated training of radiologists, and establishment of standard practice guidelines and accreditation. In the end, I believe that none of these challenges will prove to be insurmountable.
Absent peritoneal fluid on screening trauma ultrasonography in children: A prospective comparison with computed tomography☆

Abstract Background: Although the accuracy of focused abdominal sonography for trauma (FAST) in adults has been demonstrated, results of this technique in children have been conflicting with few comparisons against computed tomography (CT), the imaging gold standard. Methods: A total of 160 hemodynamically stable pediatric trauma victims referred for abdominal CT initially underwent rapid screening sonography looking for free fluid. Both studies were interpreted in blinded fashion. Results: Forty-four of the 160 patients had an intraabdominal injury on CT, 24 (55%) of which had normal screening sonography. Fifteen of the 44 (34%) had no free fluid on either modality. Accuracy of sonography compared with CT was 76% with a negative predictive value 81%. Conclusions: Sonography for free fluid alone is not reliable to exclude blunt intraabdominal injury in hemodynamically stable children given the considerable percentage of injured patients without free fluid. J Pediatr Surg 36:565-569. Copyright © 2001 by W.B. Saunders Company.
The impact of changing flow regimes on riparian vegetation and the riparian species mimulus guttatus

Alteration of riparian stream flow through the damming of rivers and streams impacts not only river morphology but also the vegetation communities that exist within the confines of a river's banks. To examine changes in vegetation community composition and structure resulting from human control of water flow, I conducted a series of surveys on dammed and undammed streams in the Eastern Sierra Nevada Mountains of California. These surveys documented that areas below dams contain increased leaf litter and grass thatch deposition, increased grass species coverage, and an altered community of existing forbs as compared to sites with naturally flowing streams. There was also an increased woody species canopy coverage as distance from the stream increased. To examine the proximal causes of damming on herbaceous plants, I set up a factorial field experiment examining the impact of grass thatch, shading, and herbivory on a common riparian species, Mimulus guttatus, the common monkeyflower. M. guttatus germination was decreased in the thatch augmentation plots and under artificial shading. For seedlings, shading increased final plant height and thatch increased herbivory. In plots where herbivory was not controlled by insecticide, M. guttatus plants grew smaller and had lower reproduction. I also repeated this experiment in a more controlled greenhouse environment using two seed sources and two levels of shading coverage. Results from this experiment largely confirm patterns seen in the field, but also revealed a strong interaction between shading and thatch treatments for both germination and growth. Overall, my results suggest that altering riparian stream flow may impact plant performance through a cascading set of biotic interactions, and that controlled releases from dams that mimic bankfull or greater discharge events may be required to restore these important and diverse communities by resetting disturbance rates.