cssi/SciSciGPT-SciSciNet huggingface dataset:
100 years of multivariate analysis

The date of birth of a field is seldom well-defined. More usually there are several key events from which a field then grows. In the case of multivariate analysis, a distinguishing feature is the relation between variables, and how are dependencies measured. Here the key ingredient was the correlation coefficient introduced by Karl Pearson. At that time there were no inferential methods, and here the year 1908 is important (exactly 100 years ago) with the introduction of Studentpsilas t-statistic. This was a univariate procedure, but it was needed before the next step could be taken. Thus from this point on multivariate procedures began to be developed. John Wishart obtained the distribution of the sample covariance matrix, and this was a central missing link for almost all future developments. Although new multivariate methods have been developed over the years, more recently there has been a resurgence of multivariate procedures in finance and in data mining. In this talk I will walk through some of the main ideas that have been the focus of research in multivariate analysis.
Constraints on Mercury's surface composition from MESSENGER neutron spectrometer data

Abstract The composition of Mercury's surface is poorly known, but the MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) mission has provided a wealth of new data from three flybys. In particular, MESSENGER Neutron Spectrometer (NS) observations reveal a surface enriched in neutron absorbing elements, consistent with interpretations of color and albedo observations suggesting a surface composition enriched in Fe–Mg–Ti oxides. In this study, we have computed the neutron absorption cross sections for all of the available proposed surface compositions of Mercury and evaluated the plausibility of each surface composition based on the neutron absorption cross section observed by MESSENGER. For identified plausible compositions, the implications for the thermal and magmatic evolution of Mercury are discussed. The measured macroscopic neutron absorption cross section of Mercury is inconsistent with a crust formed from partial melting of plausible bulk mantle compositions, flotation in a magma ocean or adiabatic melting of upwelling cumulates during magma ocean overturn. However, the observed neutron absorption is consistent with model compositions of late-stage magma-ocean cumulates and some proposed compositions from spectral modeling and equilibrium modeling. This suggests that the enrichment of neutron absorbing elements may be indicative of the processes that acted to form Mercury's crust. The enrichment in neutron absorbing elements, in combination with spectral observations that constrain FeO in silicates (
Ultrasonographic Findings and Management of Intrahepatic Biliary Tract Abnormalities After Portoenterostomy

Ultrasonographic examinations was made in 24 children who had undergone a portenterostomy to correct extrahepatic biliary atresia. Abnormalities were observed in six patients. These were the result of ongoing inflammatory reactions because all had been suffering from cholangitis after surgery, and the size of the biliary tract structure changed in accordance with the occurrence and subsidence of the cholangitis. Ultrasonographic examination showed dilation of the intrahepatic bile duct in one patient and cystic lesions in five patients. Treatment included percutaneous transhepatic bile drainage for dilated bile ducts, alcohol injections for intrahepatic cysts, and reoperation for cysts in the porta hepatis. Treatment was not required for cysts in controllable cholangitis. The results of these approaches were excellent, indicating that they were of benefit in treatment intrahepatic abnormalities occurring after portoenterostomy.
Application of Boundary Element Models to Predict Effectiveness of Coupons for Accessing Cathodic Protection of Buried Structures

Abstract Mathematical models were used to explore conditions under which a coupon provides a conservative assessment of the level of cathodic protection provided to holidays on coatings of buried s...
Laser Photophysics of Mass-Selected Hard Clusters

The new supersonic beam techniques using laser vaporization have now permitted detailed study of clusters of refractory elements. These are molecular species which offer qualitatively new challenges to theories of molecular dynamics. Aside from their size and complexity, a key new feature of these "hard" clusters is that electronic degrees of freedom are often as active in the molecular dynamics as vibrations. Three examples are given of these new dynamical problems: (1) the competition between photodissociation and photodetachment in mass-selected negative metal cluster ions, (2) the rate of desorption of small molecules chemisorbed on the surface of small metal clusters, and (3) photofragmentation pathways and rates of large positive carbon cluster ions.
Ecological perspective on water quality goals

The central assumption of nonpoint source pollution control efforts in agricultural watersheds is that traditional erosion control programs are sufficient to insure high quality water resources. We outline the inadequacies of that assumption, especially as they relate to the goal of attaining ecological integrity. The declining biotic integrity of our water resources over the past two decades is not exclusively due to water quality (physical/chemical) degradation. Improvement in many aspects of the quality of our water resources must be approached with a much broader perspective than improvement of physical/chemical conditions. Other deficiencies in nonpoint pollution control programs are discussed and a new approach to the problem is outlined.
Podiatric medicine and public health. Concepts and perspectives. Special Commission of the Podiatric Health Section of the American Public Health Association

Podiatric physicians play an important role in the field of public health. In 1975, the Podiatric Health Section of the American Public Health Association (APHA) formulated an official statement of the roles and responsibilities of podiatrists in the public health field. Entitled Functions and Educational Qualifications of Podiatrists in Public Health, the document was published in the September 1975 issue of the American Journal of Public Health. For more than 2 decades, it remained the primary document defining and delineating the activities of the specialist in podiatric public health. Recently, it was recognized that in this time of rapid change in health-care delivery, a revision of this important statement was needed. A mini-grant from the APHA in 1996-1997 supported the formation of a special commission to update the formal position of the APHA and its Podiatric Health Section with respect to podiatric public health and to provide direction for the future. This article is a shortened version of the report issued by the special commission of the APHA.
Mortimer M. Elkind, PhD, 25 October 1922 - 10 December 2000

(2001). Mortimer M. Elkind, PhD, 25 October 1922 - 10 December 2000. International Journal of Radiation Biology: Vol. 77, No. 12, pp. 1219-1220.
Left Ventricular Hypertrophy in Athletes

Left ventricular wall thickness >1.3 cm, septal-to-posterior wall ratios > 1.5, diastolic left ventricular size >6.0 cm, and eccentric or concentric remodeling are rare in athletes. Values outside of these cutoffs in an athlete of any age probably represent a pathologic state.
A method for calculating optimal inventory levels and delivery time

The following note is concerned with establishing an inventory control policy for items with extremely low demand. In the event that the expected savings in ordering cost that would result from buying in lots is less than the concomitant increase in carrying charges, it is uneconomical to use a lot size formula. In this event, it is appropriate to use a system consisting of placing orders as units are demanded.
Corticosteroid therapy of preterminal gastrointestinal cancer.

In a controlled double blind study involving 116 patients with far-advanced gastrointestinal cancer, dexamethasone at dosages of 0.75 and 1.5 mg four times daily produced improved appetite and sense of well-being in comparison to placebo treatment. This symptomatic palliation, however, was not accompanied by weight gain or improved performance status. Survival of the steroid treated patients was essentially identical to that of the placebo treated patients. Cancer 33:1607–1609, 1974.
Recent Odonata records from southern Florida - effects of global warming?

Abstract A brief Odonata survey in southern Florida, USA, in January 2000 resulted in the discovery of two new species, Chrysobasis lucifer and Nehalennia minuta, for the USA and established populations of two other species, Tholymis citrina and Tramea calverti, that had been considered vagrants. Flight seasons of six additional species were extended. These records are discussed in light of the predicted effects of global warming.
Initial-boundary-value problem of the self-gravitating scalar field in the Bondi-Sachs gauge

It is shown that, in the Bondi-Sachs gauge that fixes the speed of incoming light rays to the value 1, the Einstein equations coupled to a scalar field in spherical symmetry are cast into a symmetric-hyperbolic system of equations for the scalar field, lapse and shift as fundamental variables. In this system of equations, the lapse and shift are incoming characteristic fields, and the scalar field has three components: incoming, outgoing and static. A constraint-preserving boundary condition is prescribed by imposing the projection of the Einstein equation normal to the boundary at the outer value of the radial coordinate. The boundary condition specifies one of the two incoming metric fields. The remaining incoming metric field and the incoming scalar field component need to be specified arbitrarily. Numerical simulations of the scattering of the scalar field by a black hole in the nonlinear regime are presented that illustrate interesting facts about black-hole physics and the behavior of the characteristic variables of the problem.
Nonlinear vibrations of a pre-stressed laminated thin plate

In this communication, we present the numerical analysis of nonlinear vibrations of a pre-stressed, laminated, thin, square plate. The laminate is modeled as an isotropic nonlinear plate with effective elastic properties and the model is validated experimentally. The geometrically nonlinear vibrations are analyzed using the finite difference method, and the time integration technique based on the Newmark method combined with the fixed-point iterations to satisfy compatibility. The system exhibits behavior similar, but not identical, to the standard Duffing oscillator. Superharmonics are examined using phase space representation, Fourier transforms, deflection history, and centerline deflection shapes. The deflection shapes show significant presence of higher order spatial harmonics.
Tribochemical and Thermochemical Reactions of Stearic Acid on Copper Surfaces Studied by Infrared Microspectroscopy

The tribochemistry of copper with stearic acid was studied using a pin-on-disc wear tester under boundary lubrication conditions. Wear, as measured by surface profilometry, indicated that stearic acid was able to reduce the wear fourfold. Surface analysis by Fourier Transform Infrared (FTIR) microspectroscopy revealed that cupric stearate was formed during the rubbing process by tribochemical reactions. The reaction product was confirmed by model compounds and was also found to be comparable with those from the static thermal experiments of stearic acid on copper surface at 140°C-160°C. The affinity between the chemisorbed stearic acid and bidentate copper stearate complex is believed to be responsible for the formation of a protective film on the copper surfaces to reduce the wear from further propagation. Presented at the 46th Annual Meeting in Montreal, Quebec, Canada April 29–May 2, 1991
Commentary on “The articulation of symbol and mediation in mathematics education” by Moreno-Armella and Sriraman

In this paper the author critiques and comments on the global ideas presented by Moreno-Armella & Sriraman (2005) on the development of representational systems drawn from the prehistory and history of mathematics, their discussion of tools and technology as mediators of mathematical action and cognition and the claim that we regard present-day computational media as mediators and mathematics itself as constituting “symbolic technology”.
Mucocutaneous complications of intraarterial 5-bromodeoxyuridine and radiation

5-Bromodeoxyuridine (BUDR), a halopyrimidine thymidine analogue, is incorporated into the DNA of dividing cells and causes photoradiosensitization. Twenty-five patients with malignant astrocytomas were treated with continuous intracarotid BURR radiosensitization and radiotherapy for 8 ½ weeks. Unique dose-limiting mucocutaneous complications were encountered. Ipsilateral facial dermatitis with epilation of eyebrows and eyelashes, ocular irritation, and bilateral nail dystrophy developed in all patients. Less common reactions included oral ulceration in six patients, body exanthem on the trunk in five, and atypical erythema multiforme major in one.
Swinging for the Fences: The Effects of Ceo Stock Options on Company Risk Taking and Performance

We unpack the concept of managerial risk taking, distinguishing among three of its major elements: the size of an outlay, the variance of potential outcomes, and the likelihood of extreme loss. We ...
Lack of [3H]quinuclidinyl benzylate binding to biologically relevant binding sites on mononuclear cells.

Abstract We analyzed the binding characteristics of [ 3 H]quinuclidinyl benzylate ([ 3 H]QNB), a muscarinic cholinergic ligand, to rat and human mononuclear cells (MNC). Under various assay conditions, atropine-sensitive, saturable binding occurred with an apparent K d of 10 n M . Conditions which disrupted the MNC membrane reduced total binding and eliminated specific binding. Muscarinic agonists were unable to inhibit [ 3 H]QNB binding to MNC at concentrations up to 10 −2 M . Stereoisomers dexetimide and levetimide were equipotent inhibitors of binding (IC 50 2 × 10 −5 M ). We conclude that, although atropine-sensitive binding of [ 3 H]QNB to MNC occurs, the binding is not consistent with the presence of a biologically relevant muscarinic cholinergic receptor.
Essential Role of Urease in Germination of Nitrogen-Limited Arabidopsis thaliana Seeds

In Arabidopsis thaliana, urease transcript levels increased sharply between 2 and 4 d after germination (DAG) and were maintained at maximal levels until at least 8 DAG. Seed urease specific activity declined upon germination but began to increase in seedlings 2 DAG, reaching approximately 75% of seed activity by 8 DAG. Urea levels showed a small transient increase 1 DAG and then approximately paralleled urease activity, reaching maximal levels at approximately 9 DAG. Urease inhibition with phenylphosphorodiamidate resulted in a 2- to 4-fold increase in urea levels throughout seedling development. Arginine pools (0-8 DAG) changed approximately in parallel with the urea pool. Consistent with arginine being a major source of urea, arginase activity increased 10-fold in the interval 0 to 6 DAG. Allopurinol, a xanthine dehydrogenase inhibitor, had no effect on urea levels up to 3 DAG but reduced the urea pool by 30 to 40% during the interval 5 to 8 DAG, suggesting that purine degradation contributed to the urea pool well after germination, if at all. in aged Arabidopsis seeds, there was correlation between phenylphosphorodiamidate inactivation of urease and germination inhibition, the latter overcome by NH4NO3 or amino acids. Since urease activity, urea precursor, and urea increase in young seedlings, and since urease inactivation results in a nitrogen-reversible inhibition of germination, we propose that urease recycles urea-nitrogen in the seedling.
WE‐C‐BRA‐04: Stability of FLT and Cu‐ATSM PET in Canine Patients during Radiotherapy: Possible Targets for Dose Painting

Purpose: In dose painting, functional imaging is used to identify and target radiotherapy‐resistant regions of the tumor. It is important to know if target locations remain stable during radiotherapy, otherwise dose plans will need to adapt to mid‐therapy changes. This study investigated the spatio‐temporal stability of FLT and Cu‐ATSM PET after a few fractions of radiotherapy.Methods: Nineteen canine patients with nasal tumors (12 carcinoma and 7 sarcoma) were imaged prior to accelerated hypofractionated radiotherapy with [F‐18]FLT PET/CT for proliferation and [Cu‐61]Cu‐ATSM PET/CT for hypoxia. FLT scans were repeated after two fractions (8.4 or 10 Gy) and Cu‐ATSM scans after three fractions (12.6 or 15 Gy). Patients were immobilized with custom bite blocks and vacuum mattresses for reproducible positioning. Mid‐treatment scans were rigidly registered to pre‐treatment scans. Spearman correlation coefficients quantified the voxel‐by‐voxel SUV correlations between pre‐ and mid‐treatment scans. Population and histology averaged correlation coefficients were determined using Fisher transformations. SUVmax, SUVmean, SUVpeak, and SUVtotal were also compared between pre‐ and mid‐treatment scans using paired t‐tests. Results: Pre‐ and mid‐treatment scans were highly correlated, for both FLT and Cu‐ATSM PET distributions. The Fisher‐weighted mean Spearman correlation coefficient was 0.87[range: 0.57–0.95] for Cu‐ATSM and 0.79[0.18–0.90] for FLT. On average, sarcomas had slightly higher correlations (0.88) than carcinomas (0.78). We observed significant reductions (p 0.20) were observed in sarcomas.Conclusion: Spatial distributions of hypoxia and proliferation were stable after a few fractions of radiotherapy. The magnitude of proliferation reduced significantly in both sarcoma and carcinomatumors. The magnitude of hypoxia only reduced significantly in carcinomatumors. With high spatial stability early during radiotherapy, pre‐treatment FLT and Cu‐ATSM PET are potential candidates for dose painting targets.
Kaposi's sarcoma and the acquired immune deficiency syndrome. Treatment with recombinant interferon alpha and analysis of prognostic factors

Interferon alfa-2a (Roferon-A, Hoffmann-La Roche Inc., Nutley, NJ) was used to treat sequential groups of patients with Kaposi's sarcoma associated with the acquired immune deficiency syndrome (AIDS). Major antitumor effects (complete or partial responses) were observed in 38% of the patients treated initially with high-dose interferon alfa-2a and in 17% of patients in whom the dose was increased after low-dose treatment failed. A low dose of interferon alfa-2a was ineffective; one patient (3%) showed a partial response. Patients whose tumors responded to interferon treatment showed a significantly lower rate of opportunistic infection, as well as a longer survival than nonresponders. The status of pretreatment immune function was important in predicting the response to interferon treatment. The implication of these findings with respect to understanding the mechanism of action of interferon and the definition of the most appropriate patients for interferon treatment are discussed.
A long-range air pollution transport model for eastern north america—I. Sulfur oxides

Abstract This paper describes a Lagrangian model for simulating long-range air pollution transport over eastern North America. One version (denoted ENAMAP-2S) uses emissions inventories and standard daily weather reports to compute the airborne concentrations of SO 2 and sulfate, and their deposition on the earth's surface. A separate version of the model (ENAMAP-2N) applies to oxides of nitrogen. These versions of the ENAMAP model include the influences of smoothed terrain on the winds, and divide the atmospheric boundary layer into three parts, allowing pollutant emissions to be divided among the layers. Vertical mixing is controlled by diffusion coefficients computed from wind shear, stability, and knowledge of the mixing depth. The transformation and wet and dry deposition rates are based on recently published values. The models have been used to compute monthly average values of concentrations and depositions for January and August 1977. Typical examples are shown. The sensitivity of the output fields of ENAMAP-2S to values selected for input parameters (e.g. transformation rate of SO 2 to sulfate and deposition rates) has been studied; and based on present information, optimum values of the parameters are given. The model results include geographical patterns of pollutant concentration and deposition, and interregional exchange tables that show how much of the pollution in a certain region was emitted locally and how much originated in other specified areas. The simulated monthly airborne concentrations of SO 2 and sulfate are generally within a factor of 2 of measured values.
Two- and three-dimensional transient thermoelastic analysis by BEM via particular integrals

Abstract Particular integral formulations are presented for two- and three-dimensional transient uncoupled thermoelastic analysis. These formulations differ from previous particular integral formulations in that the equation of uncoupled thermoelasticity including the heat conduction equation is fully satisfied to obtain particular integrals. The equation of the steady-state thermoelasticity is now used as the complementary solution and two global shape functions are considered to approximate the transient term of the heat conduction equation so that two sets of particular integrals could be derived. The numerical results for both sets of particular integrals are given for three example problems and compared with their analytical solutions.
Assessing White Racial Consciousness and Perceived Comfort with Black Individuals: A Preliminary Study

This research examined the relationship between White racial consciousness development and perceived comfort with Black individuals. Participants were 339 White undergraduate students from a large southeastern state university who were asked to complete a two-part inventory: part one measuring White racial consciousness development (a five-stage scale) and part two measuring perceived comfort in situations involving Black individuals. An eta coefficient was calculated, providing evidence for the existence of a strong curvilinear relationship between White racial consciousness and perceived comfort with Black individuals η =.23 at p<.0001. These findings suggest that Whites who are completely foreclosed (stage one) or who are well acquainted with Blacks (stage five) are more comfortable in situations with Blacks than Whites who had a moderate amount of contact with them (stages two, three, and four).
Adaptation of Oriented and Unoriented Color-Selective Neurons in Human Visual Areas

Primary visual cortex contains at least two distinct populations of color-selective cells: neurons in one have circularly symmetric receptive fields and respond best to reddish and greenish light, while neurons in another have oriented receptive fields and a variety of color preferences. The relative prevalence and perceptual roles of the two kinds of neurons remain controversial, however. We used fMRI and a selective adaptation technique to measure responses attributable to these two populations. The technique revealed evidence of adaptation in both populations and indicated that they each produced strong signals in V1 and other human visual areas. The activity of both sets of neurons was also reflected in color appearance measurements made with the same stimuli. Thus, both oriented and unoriented color-selective cells in V1 are important components of the neural pathways that underlie perception of color.
Regiospecific design strategies for 3-arylpolythiophenes with pendant stable radical groups

Carbon—carbon bond-forming polymerization of 2-bromo-3-(3′,5′-di-t-butyl-4′-methoxyphenyl)-thiophene yields poly[3-(3′,5′-di-t-butyl-4′-methoxyphenyl)-2,5-thienylene] with regiospecific connectivity and a degree of polymerization of about six. Lewis-acid-moderated-cleavage of the methoxy groups on the pendant phenyl group yield the corresponding polyphenolic polymer, which is oxidized under solution conditions to yield the title polyradical. Poly[3-(3′,5′-di-t-butyl-4′-oxyphenyl)-2,5-thienylene] exhibits a strong, persistent electron spin resonance spectrum and a UV–visible spectrum consistent with formation of the pendant phenoxyl spin-bearing units. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 779–788, 1999
Prophylactic Central Neck Dissection and Local Recurrence in Papillary Thyroid Cancer: A Meta-analysis

The effectiveness of prophylactic central neck dissection (pCND) in the treatment of patients with papillary thyroid carcinoma (PTC) to prevent local recurrence is controversial. We performed a meta-analysis to assess the effect of pCND on local recurrence in PTC. Exhaustive search of online search engines identified five retrospective studies that compared the local recurrence rates of PTC in patients without clinically detectable nodal disease in patients undergoing thyroidectomy + pCND (group A) to those undergoing thyroidectomy alone (group B). A meta-analysis was performed by the fixed effects method. Recurrence was documented by imaging, thyroglobulin detection, or reoperation. Location of recurrence was identified in either the central or lateral neck compartment. A total of 1264 patients were included, 396 in group A and 868 in group B. Follow-up ranged from 6 months to 27 years. The overall recurrence rate was 2.02% in group A versus 3.92% in group B (odds ratio [OR] = 1.05, 95% confidence interval [95% CI] 0.48–2.31). The recurrence rate in the central neck compartment in group A was 1.86% compared to 1.68% in group B (OR = 1.31, 95% CI 0.44–3.91). The recurrence rate in the lateral neck compartment in group A was 3.73% compared to 3.79% in group B (OR = 1.21, 95% CI 0.52–2.75). There was no statistically significant difference in the OR in the local recurrence between the two groups. This meta-analysis indicates that pCND does not greatly reduce local recurrence in thyroid cancer. However, the available studies have substantial limitations and a prospective multicenter study to determine the indications for pCND is warranted.
Visualization tools for presenting and analysis of global landscapes of vaccine targets

Immunology produces large amounts of complex and hierarchical data. The overwhelming quantities and complexity of these data present a challenge for immunologists trying to interpret results, extract useful information, and derive new knowledge. Visualization plays an increasingly important role in the process of analyzing and understanding immunological data. We employed two visualization modules — heat map and stack graph, to be embedded in MULTIPRED2, a computational system for antigenic analysis and support of large-scale vaccine studies. We have described two complementary modules that display complex information on antigenic targets from proteins. The heat map enables visualization of large number of HLA variants, their groupings within the supertypes, and identification of antigenic regions within a query protein sequence. The stack graph is an interactive tool that presents predicted immunogenicity of a query protein across multiple HLA supertypes at human population level. The stack graph enables zooming in and out facilitating visualization at desired level of detail. Both visualization tools present a large amount of information in a single graphical display. The goal of visualization tools is to help immunologists and vaccine researchers to gain rapid insight into the data using comprehensive but clear graphic representation and summarization.
Thrombin is an important mediator of platelet aggregation in stenosed canine coronary arteries with endothelial injury.

Abstract Cyclic variations in coronary blood flow (CFVs) in dogs with experimental coronary artery stenosis and endothelial injury appear to result primarily from the aggregation of platelets at the site of stenosis followed by dislodgement and distal embolization. Using this canine model, we tested the hypotheses: (a) that thrombin is an important mediator of CFVs in dogs with coronary stenoses and endothelial injury; (b) that inhibition of thrombin with heparin, or MCI-9038, a selective thrombin inhibitor, abolishes CFVs in this model; and (c) that abolition of CFVs by thrombin inhibition is time dependent. CFVs, produced in open-chest dogs by placing a flow-reducing plastic constrictor around the left anterior coronary artery, were monitored for either 30 min (group I) or 3 h (group II) before treatment with either heparin or 4-methyl-1-(N2-[(3-methyl-1,2,3,4-tetrahydro-8-quinolinyl (MCI-9038). In group I, cyclic flow variations were abolished by heparin in 12 of 18 dogs and by MCI-9038 in 5 of 7 dogs. In group II, cyclic flow variations were not abolished by heparin in any of seven dogs and were abolished by MCI-9038 in only one of seven dogs. Thus, (a) thrombin appears to be an important mediator of cyclic flow variations in dogs with coronary artery stenosis and endothelial injury and (b) inhibition of thrombin abolishes CFVs after short but not prolonged periods of CFVs.
1K-2 Improved Axial Resolution Using Pre-enhanced Chirps and Pulse Compression

Improving the resolution of an ultrasound imaging device can have broad clinical impact. A novel pulse compression technique is developed that improves the axial resolution of an ultrasound imaging system and provides a boost in the echo signal-to-noise ratio (eSNR). The new technique, called the resolution enhancement compression (REC) technique, was validated with simulations and experimental measurements. The technique relies on exciting the source with a pre-enhanced frequency-modulated (FM) chirp that is found from application of convolution equivalence. Convolution equivalence is used to equate the pre-enhanced FM chirp convolved with the impulse response of the source of finite bandwidth with a linear FM chirp convolved with the impulse response of a source of larger bandwidth. The REC technique uses the linear chirp to compress the excitation waveform resulting in an impulse response with a bandwidth larger than the impulse response from conventional pulsing methods. Simulations and experimental measurements were conducted to validate the REC technique. Image quality was examined in terms of three metrics: the eSNR, the bandwidth, and the modulation transfer function (MTF). The simulations were conducted with a weakly-focused single-element ultrasound source with a center frequency of 5 MHz. The experimental measurements were carried out with a single-element transducer (f/3) with a center frequency of 2.25 MHz. Measurements were taken from a planar reflector and wire targets. In simulations, the axial resolution of the ultrasound imaging system was almost doubled using the REC technique versus conventional pulsing techniques. The axial resolution measured from MTF curves was 0.14 mm and 0.27 mm, respectively. The -3-dB bandwidth was almost doubled from 47% to 96% and maximum range sidelobes were -50 dB. Experimental measurements conducted using the single-element transducer also revealed an improvement in axial resolution using the REC technique versus conventional pulsing. The axial resolution from the MTF curves was 0.31 mm and 0.44 mm, respectively. The -3-dB bandwidth was doubled from 56% to 113% and maximum range sidelobes were observed at -45 dB. In addition, a significant gain in eSNR (9.2 to 16.2 dB) was achieved in both simulations and experiments. Improvement in axial resolution, doubling of the system bandwidth, and a gain in eSNR were achieved with the REC technique with range sidelobe levels compatible with ultrasound imaging systems
Performance measurement and modeling of component applications in a high performance computing environment: a case study

Summary form only given. We present a case study of performance measurement and modeling of a CCA (common component architecture) component-based application in a high performance computing environment. Component-based HPC applications allow the possibility of creating component-level performance models and synthesizing them into application performance models. However, they impose the restriction that performance measurement/monitoring needs to be done in a nonintrusive manner and at a fairly coarse-grained level. We propose a performance measurement infrastructure for HPC based loosely on recent work done for grid environments. A prototypical implementation of the infrastructure is used to collect data for three components in a scientific application and construct their performance models. Both computational and message-passing performance are addressed.
Slackened Memory Dependence Enforcement: Combining Opportunistic Forwarding with Decoupled Verification

An efficient mechanism to track and enforce memory dependences is crucial to an out-of-order microprocessor. The conventional approach of using cross-checked load queue and store queue, while very effective in earlier processor incarnations, suffers from scalability problems in modern high-frequency designs that rely on buffering many in-flight instructions to exploit instruction-level parallelism. In this paper, we make a case for a very different approach to dynamic memory disambiguation. We move away from the conventional exact disambiguation strategy and adopt an opportunistic method: we allow loads and stores to access an L0 cache as they are issued out of program order, hoping that with such a laissez-faire approach, most loads actually obtain the right value. To guarantee correctness, they execute a second time in program order to access the nonspeculative L1 cache. A discrepancy between the two executions triggers a replay. Such a design completely eliminates the necessity of real-time violation detection and thus avoids the conventional approach's complexity and the associated scalability issue. We show that even a simplistic design can provide similar performance level achieved with a conventional queue-based approach with optimisticallysized queues. When simple, optional optimizations are applied, the performance level is close to that achieved with ideally-sized queues.
Recurrent suicide attempts, self-mutilation, and binge/purge behavior: a case report.

The last decade has seen an explosive growth in the use of dialectical behavior therapy (DBT) for the treatment of borderline personality disorder (BPD). This combined individual and group therapy blends elements of learning theory, cognitive-behavioral therapy, self-psychology, and Zen Buddhism in a coherent, teachable, replicable fashion to achieve significantly lower rates of self-injurious behavior among patients with BPD. Moreover, it has increased interest among clinicians in treating this often-challenging group of patients. The following is a case report of a chronically suicidal woman treated using the DBT model in multiple settings (outpatient, partial hospital, and group home). Case material is presented along with sufficient explanation to allow readers unfamiliar with DBT to follow the formulation and interventions. Rather than being written by multiple authors, this report summarizes the experience of one clinician in presenting her clinical work to a group of nationally recognized senior DBT clinicians at the University of Washington in Seattle,* where this form of treatment originated.
Equilibrium encapsulation of polystyrene latex particles

We have performed a series of seeded styrene emulsion polymerizations in which the second stage of growth was initiated only after the second-stage monomer charge had achieved equilibrium saturation with the seed particles. The final particles were observed in the electron microscope by using two means of distinguishing between the first- and second-generation polymer: (a) butadiene tagging and osmium tetroxide staining coupled with ultramicrotomy and (b) tritiated-styrene tagging coupled with autoradiographic detection. We find that the first- and second-generation polymer chains are not uniformly mixed throughout the final latex product; rather, the second-generation polymer overcoats the seed polymer in a core–shell fashion. In order to explain these results, we present the viewpoint that monomer actually concentrates at the periphery of the swollen particle to form a monomer-encapsulated structure, rather than swelling the particle uniformly as has always been envisioned. We believe the encapsulation phenomena to be governed by the microscopic thermodynamic environment of the latex particles which has, in turn, a profound effect upon the conformational behavior of the long-chain polymer molecules as they interact with the particle–water interface.
Lifting Titan's Veil: Exploring the Giant Moon of Saturn

It is a relatively well-kept secret among planetary scientists that Saturn's moon Titan is not merely the second largest satellite, but one of the most complex and interesting bodies in our solar system. Its complex organic chemistry, which includes hydrocarbon lakes, rain, and perhaps even rivers, make it in some ways more like Earth. Indeed, Titan has been called “the Mars of the outer solar system,” not so much because of its dense atmosphere, but because of its potential to capture the public's imagination. The secret will be out and the potential for wonder is likely to be realized in full in 2004, when the Cassini spacecraft begins mapping Titan from orbit and drops the Huygens probe into its atmosphere. Lifting Titan's Veil is intended to prepare readers for that adventure; two of its stated goals are to enumerate what is currently known about Titan and to describe Cassini-Huygens and what it may reveal. The third is to offer a case history of how scientific exploration proceeds, not in a steady upward curve of progress, but in fits and starts as limited and sometimes erroneous data are gathered, interpreted, and re-interpreted.
Radiation hydrodynamics in the fluid frame

Abstract The equations of radiation hydrodynamics are derived in the fluid frame description in arbitary geometry or symmetry, inclusive of terms of order ( v / c ). This is the natural frame for the collision terms and no expansion or approximation is necessary. The equations are valid in all regimes, diffusion as well as streaming. The various energy conservation equations are shown to reduce to the well known Eulerian radiation hydrodynamic equations, provided the distinction is made between the local proper fluid-frame time and the lab frame time.
OURSELVES, OUR BODIES: THIN-IDEAL MEDIA, SELF-DISCREPANCIES, AND EATING DISORDER SYMPTOMATOLOGY IN ADOLESCENTS

Abstract Research has shown that exposure to thin-ideal media is related to eating disorder symptomatology, yet little is known about the processes underlying this relationship. Following self-discrepancy theory, it was predicted that body-specific self-discrepancies would mediate the relationship between thin-ideal media exposure and disordered eating. A sample of 366 male and female adolescents participated in two studies. The findings of the first study support the mediation prediction for thin-ideal television and ideal discrepancies. The findings of the second study demonstrate that exposure to a thin-rewarded portrayal activated ideal discrepancies, whereas exposure to a fat-punished portrayal activated ought discrepancies. Activation of both types of discrepancies is associated with an increase in negative affect whose chronic presence is predictive of disordered eating. Discussion focuses on the utility of self-discrepancy theory in synthesizing the growing collection of studies demonstrating indi...
Optimizing hemodynamic support in septic shock using central and mixed venous oxygen saturation.

Severe sepsis (acute organ dysfunction secondary to infection) and septic shock (severe sepsis plus hypotension not reversed with fluid resuscitation) are major health care problems, affecting millions of individuals around the world each year, killing one in four patients (and often more), and increasing in incidence. 1 Sepsis represents a continuum from an inciting infectious event and host-pathogen interaction to the hemodynamic consequences caused by the relationship among proinflammatory, anti-inflammatory, and apoptotic mediators and is associated with circulatory insufficiency from hypovolemia, myocardial depression, increased metabolic rate, and vasoregulatory perfusion abnormalities eventually leading to an imbalance between tissue oxygen supply and demand, causing global tissue hypoxia. 2 Studies have shown a tendency for increased oxygen consumption (VO2) with an increased tissue oxygen extraction during initial hypodynamic or normodynamic circulation. 3 Later in the hyperdynamic circulation, when cardiac output and systemic oxygen delivery (DO2) are augmented therapeutically to 50% to 80% above normal values, an associated elevation of global VO2 may be seen. 3 In nonsurvivors, oxygen extraction may be impaired at supranormal values of DO2 in the presence of peripheral tissue hypoxia. 4 The presence of elevated blood lactate concentrations suggests tissue hypoxia and indicates continued impairment of Vo2 with supranormal DO2. 3 Autopsy data on patients have failed to reveal the cause of death in patients with sepsis. Necrosis
Digital computation of inverse Laplace transforms

This note describes an algorithm for the digital computation of the inverse Laplace transform of a function containing multiple real or complex poles and discusses its advantages and disadvantages.The algorithm utilizes a well-known, simple mathemat ical technique to evaluate a polynomial and its derivatives at a root of the polynomial. This method allows the nvmerator and denominator polynomials of the function to be treated separately by dividing each repeatedly by a first-order term. Syntheticdivision of a first-order term into a polynomial when both contain complex coefficients is particularly suited to digital computation. Execution times for Pottle's algorithm and the algorithm proposed in this paper are compared. The paper concludes with a BASIC program which implements the latter algorithm.
Improvement in finite wordlength FIR digital filter design by cascading

The design of finite/wordlength finite impulse response, (FIR) digital filters is of much interest and importance in practical digital systems. In fixed-point implementations of digital filters, the designer is allowed only a finite number of bits for each coefficient. In general, the best choice for the finite wordlength coefficients is neither the truncated nor rounded infinite-precision values. A new method for quantizing cascaded subfilters to produce an overall filter that improves upon or compares favorably with the optimal quantized direct-form implementation is introduced. In particular, this method enhances performance in designs requiring deep stopband suppression, which is very common in applications. By cascading subfilters, it is possible to improve the stopband suppression. A difficulty with designing cascaded subfilters is the nonlinearity of the problem. A Taylor series approximation is used to develop a linear integer program for the optimal cascaded coefficients, improving the stopband suppression with no additional loss in the passband deviation. >
Mutant analysis and cellular localization of the AlgI, AlgJ, and AlgF proteins required for O acetylation of alginate in Pseudomonas aeruginosa

Alginate is an extracellular polysaccharide produced by mucoid strains of Pseudomonas aeruginosa that are typically isolated from the pulmonary tracts of chronically infected cystic fibrosis patients. Alginate is a linear polymer of d-mannuronate and l-guluronate with O-acetyl ester linkages on the O-2 and/or O-3 position of the mannuronate residues. The presence of O-acetyl groups plays an important role in the ability of the polymer to act as a virulence factor, and the algF, algJ, and algI genes are known to be essential for the addition of O-acetyl groups to alginate. To better understand the mechanism of O acetylation of alginate, the cellular locations of the AlgI, AlgJ, and AlgF proteins were determined. For these studies, defined nonpolar algI, algJ, and algF deletion mutants of P. aeruginosa strain FRD1 were constructed, and each mutant produced alginate lacking O-acetyl groups. Expression of algI, algJ, or algF in trans in the corresponding mutant complemented each O acetylation defect. Random phoA (alkaline phosphatase [AP] gene) fusions to algF, algJ, and algI were constructed. All in-frame fusions to algF and algJ had AP activity, indicating that both AlgF and AlgJ were exported to the periplasm. Immunoblot analysis of spheroplasts and periplasmic fractions showed that AlgF was released with the periplasmic contents but that AlgJ remained with the spheroplast fraction. An N-terminal sequence analysis of AlgJ showed that its putative AlgJ signal peptide was not cleaved, suggesting that AlgJ is anchored to the cytoplasmic membrane by its uncleaved signal peptide. AP gene fusions were also used to map the membrane topology of AlgI, and the results suggest that it is an integral membrane protein with seven transmembrane domains. These results suggest that AlgI-AlgJ-AlgF may form a complex in the membrane that is the reaction center for O acetylation of alginate.
Design of Rate-Compatible Irregular Repeat Accumulate Codes

We consider the design of efficient rate-compatible (RC) irregular repeat accumulate (IRA) codes over a wide code rate range. The goal is to provide a family of RC codes to achieve high throughput in hybrid automatic repeat request (ARQ) scheme for high-speed data packet wireless systems. As a subclass of low-density parity-check codes, IRA codes have an extremely simple encoder and a low-complexity decoder while providing capacity approaching performance. We focus on a hybrid design method which employs both puncturing and extending. We propose a simple puncturing method based on minimizing the maximal recoverable step of the punctured nodes. We also propose a new extending scheme for IRA codes by introducing the degree-1 parity bits for the lower rate codes and obtaining the optimal proportions of extended nodes through density evolution analysis. The throughput performance of the designed RC-IRA codes in hybrid ARQ is evaluated for both AWGN and block fading channels. Simulation results demonstrate that our designed RC codes offer good error correction performance over a wide rate range and provide high throughput, especially in the high and low signal-to-noise ratio regions.
THE SYNTHESIS AND TURNOVER OF RAT LIVER PEROXISOMES : IV. Biochemical Pathway of Catalase Synthesis

Early events in the biosynthesis of liver catalase were studied on female rats receiving [ 3 H]leucine or [ 3 H]δ-aminolevulinic acid or a mixture of [ 3 H]leucine with [ 14 C]δ-aminolevulinic acid by intraportal injection. Catalase antigen was selectively separated from homogenates by immunoprecipitation, both without and after partial purification of the enzyme. Label from both precursors appeared first in immunoprecipitable material which was lost upon purification of catalase; the label subsequently became associated with material indistinguishable from catalase. Kinetic analysis of the results indicates that the nonpurifiable material identified by early labeling consists of two distinct biosynthetic intermediates, the first lacking heme and representing about 1.6% of the total catalase content or 13 µg/g liver, the second containing heme and representing about 0.5% of the total catalase content or 4 µg/g liver. The first intermediate migrates at the same rate as catalase upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and therefore has a monomeric molecular weight of about 60,000.