cssi/SciSciGPT-SciSciNet huggingface dataset:
Energetics of Control Moment Gyroscopes as Joint Actuators

acts only along the joint axis, eliminating undesirable gyroscopic reaction torques. Both analysis and simulation of a single-link robotdemonstrate thatthecontrol momentgyroscopepower isequal totheequivalentjointmotorpower for a large range of gimbal inertias and maximum gimbal angles. The transverse rate of the link does not affect this result.Atwo-link robot withorthogonal joint axes givesresultssimilar tothe single-link systemunless momentumis not conserved about the joint. For a two-link robot with parallel joint axes, control moment gyroscopes outperform joint motors in power required when the joints rotate with opposite sign; the reverse is true when the joints act in unison. These surprising differences arise because control moment gyroscopes produce body torques with a zerotorque boundary condition at the joint, whereas joint motors produce torques that are reacted onto two adjacent links. The analysis concludes with pros and cons of control moment gyroscopes as robotic joint actuators.
Efficacy of Human Immunoglobulin and Penicillin G in Treatment of Experimental Group B Streptococcal Infection

ABSTRACT: In an effort to develop more effective therapy for neonatal group B streptococcal infections, penicillin G and human immune serum globulin (ISG), alone and in combination, were evaluated for their therapeutic efficacy against experimental group B streptococcal bacteremia and meningitis in newborn rats. Infected rats received either penicillin G (200 mg/kg/day), ISG (2 g/kg) or penicillin G (200 mg/kg/day) + varying doses of ISG (0.25 to 2 g/kg). All animals receiving ISG alone died; otherwise, mortality rates did not differ significantly (17-30%). Therapy with penicillin G alone and in combination with ISG was equally effective in completely eradicating group B streptococcal from blood and cerebrospinal fluid. However, combinations of penicillin G and ISG were significantly more beneficial than penicillin G alone, as shown by a significantly lower incidence of bacteremia at the end of 1 day of therapy and by greater opsonophagocytic activity in sera of animals receiving penicillin G + ISG. These findings indicate that administration of ISG in conjunction with penicillin G rapidly clears bacteria from blood, suggesting that ISG may be a useful adjunct to antimicrobial therapy of neonatal group B streptococcal disease.
A count-dependent filter for smoothing flow cytometric histograms.

An adaptive count-dependent algorithm for smoothing statistically limited histograms has been developed. It considers both the spatial frequency limitations of the measurement system (described by the measurement system point spread function) and the reliability of the measured data (indicated by the effective number of counts influencing each channel of the histogram). Windows for smoothing flow cytometric histograms are derived from an assumed Gaussain-shaped point spread function (PSF) with a constant coefficient of variation. The windows are developed by scaling the variances of the Gaussian functions inversely with the statistical reliability of the data contained in each channel of the measured histogram. The reliability of this data is determined by taking the square root of the number of counts influencing the value tabulated for each channel. Using the algorithm, a smoothed version of the measured histogram may be developed from a linear sum of the products of the individual scaled Gaussian functions and the original measured histogram. Data are presented demonstrating the advantages of count-dependent smoothing over non-count-dependent smoothing using synthesized DNA histograms as a function of sample size.
Selective Chemical Mechanical Polishing Using Surfactants

Device fabrication using high density, small pattern size shallow trench isolation (STI) processes requires material removal selectivity during chemical mechanical polishing (CMP) steps for optimum product processing and quality control. To improve the selectivity of STI CMP processes, surfactants were applied to selectively polish silica as opposed to silicon nitrides surfaces. A ten-fold increase in selectivity over conventional colloidal silica slurry was achieved by the addition of sodium dodecyl sulfate (SDS) and pH adjustment. Adsorption characteristics of SDS on silica and silicon nitride were measured as a function of slurry pH and concentration of SDS. As indicated by streaming potential measurements and solution depletion adsorption experiments under acidic pH conditions, SDS adsorption on silicon nitride was significantly higher than silica primarily due to the electrostatic interactions. It was concluded that the preferential adsorption of SDS on silicon nitride results in the formation of a material-selective self-assembled passivation (lubrication) layer leading to selective polishing. Effects of different alkyl chain length of surfactants were tested. Various mixed surfactant systems were tested and it is believed that the addition of second surfactants promotes the adsorption on silica diminishing selectivity. The material-targeted boundary layer lubrication concept may be used to develop selective CMP polishing slurries.
FACTORS IN THE PRODUCTION OF 90/10 TIN BRONZE COMPONENTS OF HIGHER DENSITY (7·4 g/cm3)*

AbstractA study has been made of the production of a 90/10 tin bronze by powder metallurgy at a density of 7·4 g/cm3, to meet specific mechanical property requirements. Types of powder mixes used were: (a) a mixture of elemental powders; (b) a partially pre-alloyed copper-tin powder; (c) an atomized bronze powder; (d) a mixture of atomized alloy and elemental powders.A review is given of the flow, filling, pressing, and sintering characteristics of each powder mix and the processing steps necessary to produce a finished article. The factors governing the choice of a type of powder for fabricating a part are discussed.
Continuous and pulse sonication effects on transesterification of used vegetable oil

This study reports on the effects of direct application of continuous and pulse sonication on transesterification reaction of used vegetable oil. Specific to this research, thermal effects of ultrasonics in transesterification reaction without external conventional heating along with the effects of different ultrasonic intensities and power densities were reported. Two process parametric evaluation studies were conducted to compare the effects of continuous and pulse sonication. These included methanol to oil ratio, catalyst concentration and reaction time effects on the transesterification reaction. For continuous sonication, a catalyst amount of 0.5% (wt/wt), methanol to oil ratio of 9:1 was sufficient to complete the transesterification reaction in 1–2 min at a power output of 150 W with a biodiesel yield of 93.5%. For pulse sonication, a maximum biodiesel yield of 98% was achieved at 2.5 min of reaction time, 9:1 methanol to oil ratio, and 1.25% catalyst. Generally, higher biodiesel yields were observed for pulse sonication compared to continuous sonication under any given process condition. Power density and ultrasonic intensity tests revealed that biodiesel yields were more sensitive to continuous sonication due to intense mixing. A plug-flow or contact-type reactor design may improve overall ultrasonic utilization in the transesterification reaction under continuous sonication.
Sequence analysis of human T cell lymphotropic virus type I strains from southern India: Gene amplification and direct sequencing from whole blood blotted onto filter paper

Human T cell lymphotropic virus type I (HTLV-I) infection in India has been found to be associated with adult T cell leukaemia/lymphoma (ATLL) and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) among life-long residents of southern India. To examine the heterogeneity of HTLV-I strains from southern India and to determine their relationship with the sequence variants of HTLV-I from Melanesia, 1149 nucleotides spanning selected regions of the HTLV-I gag, pol, env and pX genes were amplified and directly sequenced from DNA extracted from whole blood blotted onto filter paper and from peripheral blood mononuclear cells, obtained from one patient with HAM/TSP, two with ATLL and eight asymptomatic carriers from Andhra Pradesh, Kerala and Tamil Nadu. Sequence alignments and comparisons indicated that the 11 HTLV-I strains from southern India were 99.2% to 100% identical among themselves and 98.7% to 100% identical to the Japanese prototype HTLV-I ATK. The majority of base substitutions were transitions and silent. No frameshifts, insertions, deletions or possibly disease-specific base changes were found in the regions sequenced. The observed clustering of the Indian HTLV-I strains with those from Japan, as determined by the maximum parsimony method, suggested a common source of HTLV-I infection with subsequent parallel evolution. Amplification of DNA from blood specimens collected on filter paper may be useful for the study of other blood-borne pathogens.
The contract negotiation stage of a school-based, cross-cultural organizational consultation: A case study.

This article draws on organizational and cross-cultural consultation tenets, to analyze the contract negotiation of a school reform initiative by focusing on the contracting and cross-cultural issues that emerge at that stage. A case from one school presents illustrative examples generated and grounded by qualitative methodology using participant observation, semistructured interviews, extant records, and researcher logs. Themes related to contract negotiation that were derived from the analysis include conflicting expectations and beliefs; dissatisfactions with procedures and policies; lack of empowerment; pedagogical dissonance; and feelings of blame, inadequacy, and racism. This case highlights problems that can occur in school-based, cross-cultural organizational consultation when a rigid adherence to the content of consultation overshadows the consultation process. It is suggested that framing consultation as a coconstructed, participatory process that includes consensual contract negotiation may pro...
Analysis of a structural homology model of the 2'-O-ribose methyltransferase domain within the vesicular stomatitis virus L protein.

The large (L) proteins of non-segmented negative stranded (NNS) RNA viruses contain the core RNA dependent RNA polymerase activity for RNA replication and transcription as well as the activities for polyadenylating and capping the mRNA transcripts and for methylating the cap structures. There is currently no structural information available for these large multi-functional proteins. Phylogenetic analyses have led to the division of the L protein primary structure into six functional domains of high conservation that are linked by variable regions. The studies in this report investigate the role of specific amino acids within domain VI of the VSV L protein, which contains a 2′-O-ribose methyltransferase (MTase) domain. We generated a structural homology model of residues 1644–1842 within domain VI based on the crystal structure determined for the known 2′-O-ribose MTase of E. coli, RrmJ. The information generated by this homology model directed us to residues structurally important for MTase activity and SAM binding. Selected residues were analyzed by site-specific mutagenesis and the mutant L proteins were assayed for their effects on RNA synthesis and cap methylation. The goal of this study was to functionally test the model in order to gain insight into the structural constraints of this region of the L protein. The data presented here revealed specific mutations that affect transcription, replication, and 5′ cap methylation, many of which resulted in polymerases temperature sensitive for RNA synthesis.
Timing of neonatal cardiac surgery is not associated with perioperative outcomes.

Objective The optimal timing for neonatal cardiac surgery is unknown. We aimed to determine the relationship between age at surgery and perioperative outcomes, hypothesizing that earlier intervention would be associated with lower morbidity and mortality. Methods A retrospective review was performed of neonates who had undergone an arterial switch operation, stage 1 palliation for functional single ventricle, or systemic-to-pulmonary shunt for obstructed pulmonary blood flow from January 1, 2005, to December 31, 2010. The subjects with clinical indications for delayed surgery or prematurity were excluded. Age at surgery was evaluated as both a continuous and a categorical variable. The primary outcome was a composite endpoint of mortality or prolonged intensive care stay. Results Of 344 subjects, 286 (77 arterial switch operation, 124 stage 1 palliation, 85 systemic-to-pulmonary shunt) met the inclusion criteria. In each group, age at surgery was not associated with the primary composite endpoint. The patients who died after systemic-to-pulmonary shunt had a median age at surgery of 3 days versus 6 days for the survivors ( P = .04). A similar, but nonsignificant, pattern was seen for patients undergoing arterial switch operations (4.5 vs 7 days; P = .09). Earlier surgery was not associated with a reduced duration of vasoactive support, mechanical ventilation, or intensive care unit length of stay in any group. Stage 1 palliation subjects in the upper age quartile (≥8 days) at surgery were less likely to require prolonged mechanical ventilation ( P = .03). Conclusions Younger age at intervention in the neonatal period was not associated with reduced morbidity or mortality in any procedural subgroup studied. In our cohort, earlier systemic-to-pulmonary shunt for obstructed pulmonary blood flow was associated with a greater likelihood of a poor outcome.
Large area Cds thin film grown by chemical bath deposition

Cadmium Sulfide (CdS) thin films are often deposited on glass substrates coated with TCO layers by the close-spaced sublimation (CSS) or sputter techniques in industrial because in-line production integration. It is seldom reported that CdS is deposited by the chemical bath deposition (CBD) batch process. The bottleneck of CBD for commercial application is its low production rate and waste water treatment. In this paper, we report how to produce different thickness large area (100cm2) CdS thin film by CBD. We study how to increase the production rate. The influence of the solution temperature and concentration on the thickness of CdS is investigated.
Secondary nucleation of magnesium sulfate by fluid shear

The secondary nucleation of magnesium sulfate due to the action of fluid forces on a seed crystal was studied by introducing the hypothesized nuclei so generated into a region of high supersaturation. The number of nuclei observed is strongly dependent on the supersaturation at the seed and the severity of shear forces. Classical nucleation theory is used to interpret the results. These results are consistent with other experimental observations described in the recent literature on contact nucleation. The growth and nucleation process inferred is similar to that illustrated by Clontz and McCabe (1972) and suggested by Knight (1971).
Audio level safety limits and their impact on personal music player

Personal music players have become very common in the past decade, yet we haven't had time to see the cumulative impact of higher audio levels for longer durations on the hearing of the general public. A number of industry and governmental organizations are interested in setting audio safety limits before a large number of users risk hearing damage. Much of the existing research and regulation for safe audio levels is based on occupational exposure, yet these limits are often used as the basis for proposed audio limits for personal music players. Occupational limits are based on a fixed intensity for a defined period which is not necessarily representative of audio played on personal music players. Regulations imposed for the safety of one type of user may prevent the music player from being adequately used by listeners of other types of audio programming. This paper will look at a number of topics covering audio safety. It will discuss the basic mechanisms of audio induced hearing damage. Next, it will look at existing sound level regulations and proposed regulations along with the potential impact of those regulations. Next it will cover audio level measurement methods for personal music players, the applicable standards defining those test methods and the impact of different headphones on those measurements. Finally, it will cover the audio level profiles of different types of programming frequently played on personal music players. Using this information, various scenarios will be discussed for limiting audio levels and the risk of hearing damage from personal music players. These techniques range from a fixed maximum audio level through user acknowledged overrides to real-time dynamic level sensing and control.
Keynes and the Classics: A Dynamical Perspective

Although it is possible to draw various purely technical distinctions between modern and pre-Keynesian economics, it is mainly with respect to matters of intellectual orientation that the two are strikingly different. Many and diverse reasons have been advanced to explain why this should be so, most of them plausible, all of them fairly elaborate. The purpose of this note is to add an element of unity and simplicity to these explanations by suggesting a straight-forward dynamical interpretation of the foundations of Keynesian and classical thought.
A phase I trial of andrographolide in HIV positive patients and normal volunteers.

A phase I dose-escalating clinical trial of andrographolide from Andrographis paniculata was conducted in 13 HIV positive patients and five HIV uninfected, healthy volunteers. The objectives were primarily to assess safety and tolerability and secondarily to assess effects on plasma virion HIV-1 RNA levels and CD4(+) lymphocyte levels. No subjects used antiretroviral medications during the trial. Those with liver or renal abnormalities were excluded. The planned regimen was 5 mg/kg bodyweight for 3 weeks, escalating to 10 mg/kg bodyweight for 3 weeks, and to 20 mg/kg bodyweight for a final 3 weeks. The trial was interrupted at 6 weeks due to adverse events including an anaphylactic reaction in one patient. All adverse events had resolved by the end of observation. A significant rise in the mean CD4(+) lymphocyte level of HIV subjects occurred after administration of 10 mg/kg andrographolide (from a baseline of 405 cells/mm(3) to 501 cells/mm(3); p = 0.002). There were no statistically significant changes in mean plasma HIV-1 RNA levels throughout the trial. Andrographolide may inhibit HIV-induced cell cycle dysregulation, leading to a rise in CD4(+) lymphocyte levels in HIV-1 infected individuals.
Three-dimensional indefinite metamaterial nanocavities with anomalous scaling law

We demonstrate truly deep sub-wavelength nanoscale metamaterial optical nanocavities with anomalous scaling laws, by incorporating indefinite metamaterials with hyperbolic dispersion. Cavities with sizes down to ∼ λ/20 and high effective refractive index of 17.4 are realized.
Effects on penile reflexes and plasma hormones of hyperprolactinemia induced by MtTW15 tumors.

Abstract The effects of severe hyperprolactinemia induced by MtTW15 tumors (prolactin-and growth-hormone-secreting pituitary adenoma) on penile reflex activity and blood hormones were examined. There was no significant adverse effect of hyperprolactinemia on penile reflexes at 7, 14, or 21 days after tumor inoculation. However, a virtual elimination of penile reflex activity was observed 34 days after inoculation. Additionally, significant decrements in serum testosterone and dihydrotestosterone and an elevation in progesterone were seen at this time concomittant with greatly increased prolactin levels. The results suggest that erectile dysfunction may contribute to hyperprolactinemia-induced copulatory failure.
An Exploratory Analysis of Communication in Peer-Directed Educational Discourse.

This exploratory analysis examined the nature of asynchronous, text-based communication in peer-directed educational discussions. The nature of communication changed over time and women exhibited greater tendency for epistolary communication than men. Initial posts, which were expository in nature, focused on disseminating information whereas replies to initial posts exhibited characteristics of epistolary discourse, such as alignment and support. The study observed that men and women employed different communication styles when beginning a message thread. Initial posts by males began with epistolary statements whereas the posts of women began with expository statements.
Biological role of xanthine oxidase and tetrazolium-reductase inhibitor.

The biochemical properties of tetrazolium reductase inhibitor (“reductase inhibitor”) from beef brain and liver were compared with superoxide dismutase (erythrocuprein) from beef erythrocytes, using xanthine oxidase and xanthine as a model system. In all assays the behavior of erythrocuprein and the reductase inhibitor was identical; it is concluded that the tetrazolium reductase inhibitor is a member of the superoxide dismutase class of enzymes. Its possible identity with other proteins of this group remains to be established. Xanthine dehydrogenase is activated by natural or synthetic detergents. These compounds eliminate the enzymatic action of both erythrocuprein and reductase inhibitor. Low levels of cyanide, which do not inhibit xanthine dehydrogenase block superoxide dismutase. The biological role of xanthine oxidase is discussed. We propose that an important function of xanthine oxidase is to provide an ubiquitous source of hydrogen peroxide and superoxide radicals which serve as oxidants for coupled biological oxidations.
GLOMERULAR CAPILLARY VOLUME AND SURFACE AREA DURING ONTOGENY

The apparent discrepancy between functional glomerulotubular balance and morphologic glomerular preponderance prompted us to develop a new technique to examine if the currently accepted estimates of glomerulor tuft volume (GTV) derived from measurements of diameter bear a constant relationship to glomerular capillary volume (GCV) and capillary surface area (GCA). Kidneys of puppies were fixed in vivo and injected with silastic. GTV was calculated from measurements of the distance between filled capillary loops located at opposite poles. Counts of the neutron activated chromium contained in the silastic served for calculation of GCV. GCA = 2 GCV/r, where r = mean capillary radius. The results are expressed as mean ± SE in mm3·10−5 or mm2 · 10−5 (n=4 in each age group; 50 superficial (S) and 50 iuxtamedullary (J) were measured in each animal). Only the values observed in 6 week old animals are significantly different (p<.05)from the other age groups. in summary, GCV occupies a significantly smaller part of GTV in the newborn than in the 6 week old puppy suggesting that the so called glomerular preponderance might be artifactual.
Tick Repellents I: Ethylene Glycol Acetamides

Acetamides derived from ethylene glycol were synthesized and evaluated as repellents for the brown dog tick Rhipicephalus sanguineus. Several of these compounds showed repellency equal to the standard repellents, N,N-diethyl-m-toluamide and butopyranoxyl.
Are specialized ICUs so special

Subjects: 84,182 patients admitted to specialty and general ICUs with an admitting diagnosis or procedure of acute coronary syndrome, ischemic stroke, intracranial hemorrhage, pneumonia, abdominal surgery, or coronaryartery bypass graft surgery. ICU type was determined by a local data coordinator at each site. Patients were classified by admission to a general ICU, a diagnosis-appropriate (“ideal”) specialty ICU, or a diagnosis-inappropriate (“nonideal”) specialty ICU.
Design and Delivery of Training for International Trainees: A Case Study

One problem faced by instructional designers in multinational corporations is designing training for use with other cultures, while using resources effectively. A naturalistic case study approach was used to determine which conditions international students bring to technical training are the most critical and which aspects of the delivery of instruction are affected most critically by those traits. Respondents included students from several countries, as well as instructors. The most critical traits were value differences and language difficulty. These affected all aspects of training, but most critically the needs assessment and the instructional strategies. Critical instuctional strategies include reiterating concepts in several ways and using visuals, clear and active language, and relevant and specific examples. Effective strategies also include allowing more time for instruction, building in frequent breaks, and using media that use multiple senses and allow students to go at their own pace.
Parental toy choice stereotyping and its effects on child toy preference and sex-role typing

Toys are associated with a child's expression, fantasy, interest, exploration, construction, education, cognitive development, and sex-role learning. The present research was concerned with the influence of parental toy choice stereotyping on child toy preference and sex-role typing among nursery school children. The results indicated child toy preference was found to be significantly related to parental toy choice preference. Moreover, the parental toy choice preference was found to be associated with sex-role typing.
Initial clinical experience with Myxo-ETlogix mitral valve repair ring.

Objective Complexity of mitral valve repair for myxomatous disease has led to low adoption. We report initial experience with a new ring designed specifically for myxomatous disease, the Myxo-ETlogix (Edwards Lifesciences LLC, Irvine, Calif). Methods From March 15, 2006, through November 19, 2007, 129 patients underwent mitral valve surgery for pure myxomatous disease, and 124 valves (96.1%) were repaired. The Myxo-ETlogix ring was used in 100 cases and the Physio ring (Edwards) in 24. The Myxo-ETlogix design includes a 3-dimensional shape to reduce systolic anterior motion and a larger orifice to accommodate elongated leaflets and decrease need for sliding plasty. Direct mitral valve measurements were made. Sizing was based on A2 height, and choice of ring type was based on unresected leaflet heights. Results There was no operative mortality or lasting perioperative morbidity. The Myxo-ETlogix group had taller A2, P1, P2, and P3 leaflet segments than the Physio group (P ≤ .003). Only 1 sliding plasty was performed for asymmetry in the Myxo-ETlogix group. Predischarge and follow-up echocardiograms (n = 338 in 124 patients) disclosed transient nonobstructive chordal systolic anterior motion in 3 echocardiograms in 3 patients. No patients had 2+ or greater mitral regurgitation. At discharge, 5.7% had 1+ mitral regurgitation; this proportion was 17.3% at last follow-up (mean 6.1 ± 4.4 months). Conclusion In initial experience with the Myxo-ETlogix ring, nonobstructive systolic anterior motion has been rare and obstructive systolic anterior motion not observed. Ongoing prospective echocardiographic and clinical studies will elucidate the role of this etiology-specific ring.
Glucocorticoid-stimulated utilization of substrates in hepatic mitochondria☆

Abstract Glucocorticoids administered to rats have been found to stimulate the rates of utilization of substrates by subsequently isolated hepatic mitochondria. This stimulation was observed in the carboxylation and decarboxylation of pyruvate and in the oxidation of β-hydroxybutyrate and succinate during state 3 and uncoupled conditions. These effects were produced by cortisol, triamcinolone, and dexamethasone, but not by deoxycorticosterone. Responses to the steroids were similar to those observed after glucagon or triiodothyronine administration. The stimulation of the rate of pyruvate decarboxylation was shown to occur independently of the rate of pyruvate carboxylation. Steroids varied with respect to the time required after in vivo administration for stimulation of metabolism to occur, as well as for achievement of maximally stimulated levels. Significant stimulation was obtained within 60 min after treatment with cortisol-succinate and 90 min after dexamethasone or cortisol. Maximal stimulation was observed after 2 to 4 h of treatment. The dose dependency of the mitochondrial responses was observable in the increase in the rates of pyruvate carboxylation after dexamethasone or cortisol treatment. Of the two steroids tested, dexamethasone was approximately 2000-fold more potent than cortisol in increasing mitochondrial activity. The effects of 30 min of treatment with glucagon or 20 h with triiodothyronine were additive with the stimulation produced by glucocorticoids. Complete additivity was found in the increased rates of pyruvate carboxylation, while oxidation of substrates was approximately 75% additive.
Fast solutions to physical equilibrium and interpolation problems

Efficient solutions to physical equilibrium and interpolation problems can be obtained by using wavelet basis vectors for problem discretization or for use as a preconditioning transform. Good approximations to these solutions can be obtained in onlyO(n) operations andO(n) storage locations, a property that can be extremely useful in visualization applications.
Prediction of Stability in Pharmaceutical Preparations XIX: Stability Evaluation and Bioanalysis of Clofibric Acid Esters by High-Pressure Liquid Chromatography

Specific, sensitive, reversed-phase high-pressure liquid chromatographic assays of clofibric acid esters, clofibrate and etofibrate, and their hydrolysis products, clofibric acid and its monoglycolate and nicotinic acid and its monoglycolate, have been developed in aqueous solution and in biological fluids. Sensitivities of 100 ng/ml of injected mobile phase, a 10-fold increase over existing methods, are reported. Plasma concentrations as low as 200 ng/ml can be analyzed easily in the miscible phase after acetonitrile denaturation. The compounds and their products can be extracted with haloalkane solvents. The extracts were evaporated, reconstituted, and assayed in minimal amounts of mobile phase, resulting in sensitivities of 10 ng/ml of plasma. Conditions are presented that minimize interferences with plasma components. The assay was used to determine the stability of the clofibric acid esters in aqueous solutions, to establish log k-pH profiles at various temperatures, and to evaluate Arrhenius parameters. Hydrolysis was by specific acid-base catalysis. The initial product of etofibrate solvolysis at pH > 6 is the monoglycol ester of clofibric acid; at pH < 3, it is the monoglycol ester of nicotinic acid. Clofibric acid esters are highly unstable to mild alkali (1–3 hr at pH 10 and 30°); even in the estimated pH range of maximum stability, they have half-lives of 100–200 days at 30°. They have half-lives of 4–7 min at 37.5° in fresh dog plasma, and data presented indicate that clofibric acid monoglycolate is an inital product of etofibrate solvolysis.
Cell biology: Shaggy mouse tales.

First impressions can be misleading. The enzyme telomerase has been well studied because of its initial association with cell ageing processes and cancer — but it now seems that this is not all it can do. Regenerating tissues such as skin and blood require high rates of cell turnover, which occurs through the tightly regulated division of tissue stem cells. The genes and proteins that control stem-cell behaviour remain largely unknown, but now a critical connection between stem-cell function and the protein component of telomerase, TERT, has been discovered. Conditional activation of TERT in skin epithelium activates resting hair follicle stem cells, resulting in rapid hair growth. This is distinct from TERT's role in extending telomeres, the caps that protect the ends of chromosomes, and suggests new ways of treating disorders associated with tissue injury and ageing.
Chronic lymphocytic leukemia‐well‐differentiated lymphocytic lymphoma with monoclonal iga: IgA production by circulating lymphocytes

A patient is described in whom morphologic features of well-differentiated lymphocytic lymphoma (WDL) or chronic lymphocytic leukemia (CLL) and immunologic features of multiple myeloma were present. Studies of isolated peripheral blood lymphocytes demonstrated de novo synthesis of IgA k, the same paraprotein that was identified in the serum. Predominant IgA synthesis by peripheral lymphocytes has not been previously shown in either WDL or CLL.
Ad hoc network metrics: Which is best?

The area of wireless ad hoc networks has attracted much attention and gained great popularity in the last few years. Yet researchers are still investigating several metrics to evaluate ad hoc network performance. Furthermore, to our knowledge, no work has been published to address the comparison of different network metrics. In this paper, we analyze and compare several distinct network metrics including transport capacity, transmission capacity and network diameter, which quantify ad hoc network performance from different perspectives. We also evaluate the network metrics via simulation for two “extreme” routing strategies: “nearest neighbor” (NN) and “shortest path” (SP). Main conclusions are that the transport capacity and the transmission capacity are generally inversely related in ad hoc networks; SP routing can achieve larger transport capacity and smaller network diameter than NN routing, whereas NN routing results in larger transmission capacity than SP routing. Ultimately, the best network metric among these three depends upon application; more research is needed in this important area.
Present Day Hydro Power Practise in Central Europe

This paper represents the impressions of a European trip made during the summer of the year 1929 and gives a comparative study of the conditions of European development in so far as they are either of a particular interest or different from the conditions in the United States. The advance made in Europe in the low head developments is attributed in a large part to the advanced work made in the European hydraulic laboratories and to the cooperation between the laboratory and the manufacturer of hydraulic equipment and power plant designer. The advances made in the design of the large units of Propeller and Kaplan turbines are discussed. The low head developments are stressed as the most interesting, and a short description is given of the plants in the region of the upper Rhine and the international interconnection system of this region. The extensive pumping schemes of this region are briefly described. An attempt is made to outline the power house design tendencies and the new ideas in protecting the river bed from erosion. The more interesting work done in the hydraulic laboratories is described. A short comparison between the mixing and placing of concrete as done in Europe and in the States is given.
Identification of a gene signature in cell cycle pathway for breast cancer prognosis using gene expression profiling data

Numerous studies have used microarrays to identify gene signatures for predicting cancer patient clinical outcome and responses to chemotherapy. However, the potential impact of gene expression profiling in cancer diagnosis, prognosis and development of personalized treatment may not be fully exploited due to the lack of consensus gene signatures and poor understanding of the underlying molecular mechanisms.
Logical localization of large Internet events

The Internet occasionally experiences large disruptions, arising from both natural and manmade disturbances, and it is of significant interest to develop methods for locating within the network the source of a given disruption (i.e., the network element(s) whose perturbation initiated the event). This paper presents a new approach to realizing this logical localization objective. The proposed methodology consists of three steps: 1.) data preprocessing, in which publicly available measurements of Internet activity are acquired, “cleaned”, and assembled into a format suitable for computational analysis, 2.) event characterization via tensor factorization-based time series analysis, and 3.) localization of the source of the disruption through graph theoretic analysis. This procedure provides a principled, automated approach to identifying the root causes of network disruptions at “whole-Internet” scale. The considerable potential of the proposed analytic method is illustrated through both computer simulation studies and empirical.
Modeling Probabilistic Measurement Correlations for Problem Determination in Large-Scale Distributed Systems

With the growing complexity in computer systems, it has been a real challenge to detect and diagnose problems in today's large-scale distributed systems. Usually, the correlations between measurements collected across the distributed system contain rich information about the system behaviors, and thus a reasonable model to describe such correlations is crucially important in detecting and locating system problems. In this paper, we propose a transition probability model based on markov properties to characterize pair-wise measurement correlations. The proposed method can discover both the spatial (across system measurements) and temporal (across observation time) correlations, and thus such a model can successfully represent the system normal profiles. Problem determination and localization under this framework is fast and convenient. The framework is general enough to discover any types of correlations (e.g. linear or non-linear). Also, model updating, system problem detection and diagnosis can be conducted effectively and efficiently. Experimental results show that, the proposed method can detect the anomalous events and locate the problematic sources by analyzing the real monitoring data collected from three companies' infrastructures.
Interposition Grafts for Difficult Carotid Artery Reconstruction: A 17-Year Experience

Carotid interposition grafts (CIP) for carotid artery revascularization can be a viable alternative to carotid endarterectomy (CEA) or carotid artery stenting (CAS) for complex carotid disease. This is a retrospective review of the UCLA 17-year experience with CIP for carotid reconstruction. Carotid operations performed between 1988 and 2005 revealed 41 CIP procedures in 39 patients using polytetrafluoroethylene (PTFE, n = 31) or reversed greater saphenous vein (Vein) (n = 10). Perioperative data and long-term follow-up for each conduit were statistically compared. There were no significant differences in demographics, risk factors, operative indications, complications, or 30-day perioperative deaths. There was one postoperative stroke in each group, for an overall stroke rate of 4.9% (PTFE 3.2%, Vein 10%). There was one asymptomatic occlusion and there were two high-grade restenoses in the PTFE group compared with one asymptomatic occlusion and one high-grade restenosis in the Vein group. Overall primary patency was 90% and the assisted primary patency was 97% for the PTFE group (mean follow-up 50 months), whereas primary patency was 80% (mean follow-up 30 months) in the Vein group. CIP is a safe and effective technique with excellent long-term follow-up for complex carotid reconstruction when CEA or CAS may be contraindicated.
A theory of redo recovery

Our goal is to understand redo recovery. We define an installation graph of operations in an execution, an ordering significantly weaker than conflict ordering from concurrency control. The installation graph explains recoverable system state in terms of which operations are considered installed. This explanation and the set of operations replayed during recovery form an invariant that is the contract between normal operation and recovery. It prescribes how to coordinate changes to system components such as the state, the log, and the cache. We also describe how widely used recovery techniques are modeled in our theory, and why they succeed in providing redo recovery.
Intermodality 3D medical image registration with global search

Describes a new registration method for three-dimensional medical images. It is important clinically to bring images from different modalities into alignment so that equivalent points can be identified. Often, functional images (showing metabolism or blood flow) are registered to structural images in order to more accurately interpret and quantify these images. This is especially important in areas of decreased function. This registration method determines the optimal transformation between the images using a match metric based on the distance transform of a structure visible in both modalities. The globally optimal transform is determined using a genetic optimization method and a hybrid technique using both genetic and gradient optimization. This provides a feasible way of determining the global solution making this method robust to local minima and insensitive to initial positioning. >
How to make a flying squirrel: Glaucomys Anatomy in Phylogenetic Perspective

Molecular evidence strongly supports the derivation of flying squirrels from tree squirrels, with the sister group being the Holarctic tree squirrels (Sciurus) and their close relatives. We present a rationale for the hypothesis that the transition occurred among small squirrels, and we propose using the northern flying squirrel (Glaucomys sabrinus) and the southern flying squirrel (Glaucomys volans) as models. Thus, we compare their morphologies with similar-sized tree squirrels (the Central American dwarf squirrel [Microsciurus alfari] and the western dwarf squirrel [M. mimulus]). We compare body proportions of Glaucomys with those of Microsciurus, considering differences as potential adaptations for gliding associated with wing loading, aspect ratio, and parasitic drag. We use the following measurements: lengths of the centra of the thoracic, lumbar, sacral, and caudal vertebrae; and lengths of the long bones (humerus, radius, femur, and tibia), metacarpals, metatarsals, and proximal phalanges of the hands and feet. We then compare these proportions of Microsciurus with those of other species of Sciurini, and the proportions of Glaucomys with other species of Pteromyini, to determine if each is representative or derived within its clade. Members of the genus Glaucomys exhibit relative elongation of the lumbar vertebrae and the forearm, relevant to wing loading and aspect ratio, relative lengthening of the midcaudal vertebrae, and relative shortening of the more distal caudal vertebrae, perhaps of importance for stability and control. Members of the genus Glaucomys also have shorter hands and feet, but these appeared to be elongated in Microsciurus, rather than shortened in Glaucomys, leaving the issue of parasitic drag moot. Finally, we speculate on the genetic changes that have produced these morphological modifications and may facilitate the evolution of gliding flight.
The Science of Security versus the Security of Science

(See the perspectives by Osterholm and Relman, on pages 1636–8 and Herfst et al, on pages 1628–31, and the editorial commentary by Hirsch on pages 1621.)
Recognition of object categories using affine kernels

With the growing image collection on the web, classifying images has become an actively explored problem. In this paper we present a novel approach to the classification of images depicting objects in a category using the odd-man-out principle of visual categorization. Specifically, we build a model of an object category by noting discriminative features that are commonly observed across the member images of the class. Appearance changes due to pose, illumination and intra-class variations are modeled using multi-scale affine kernels. The best matching affine kernel for a given query image is found as the one that has the largest overlap of discriminable features that are commonly observed across the class. We show that using the odd-man-out principle of IQ tests not only results in better feature selection but also in more robust object class categorization, in comparison to the state-of-the-art methods on large benchmark image datasets.
Myosin Synthesis and Degradation during Development of Cardiac Hypertrophy in the Rabbit

Metabolism of left ventricular myosin was studied in rabbits (2.7-3.2 kg) following banding of the ascending aorta (65% occlusion). In 26 rabbits the incorporation of amino acid into myosin was determined 2, 3, 4, 9, and 15 days after either stenosis or sham operation by injecting 3H-lysine (0.5 mc/kg) 4 hours before the animals were killed. In 32 rabbits the same dose of 3H-lysine was injected 24 hours before surgery, and disappearance of isotope from myosin was measured by killing the rabbits after 3, 5, 7, 10, or 16 days. Specific radioactivity of free lysine, myosin, and total proteins was determined in left ventricular samples from each animal. The experimental results indicate that: (1) left ventricular peak systolic pressure increased from 97 to 163 mm Hg; (2) the ratio of left ventricular weight to body weight increased about 16% (3) disappearance of free 3H-lysine was similar in rabbits with aortic stenosis and those with sham operations; (4) after the second day myosin synthesis was greater in r...
Homomorphic wavelet shrinkage and feature emphasis for speckle reduction and enhancement of echocardiographic images

An approach for speckle reduction and feature enhancement under a framework of multiscale wavelet analysis is presented. The advantages of both soft thresholding and hard thresholding wavelet shrinkage techniques are utilized to eliminate noise and preserve the sharpness of salient features. We integrate a method of wavelet shrinkage with nonlinear processing to enhance contrast within structures and along object boundaries. Feature restoration and enhancement are accomplished by modifying the gain of a signal's variational energy. In this study, we focus on multiplicative noise, such as speckle noise. We show that this algorithm is capable of enhancing features of interest, such as endocardial and epicardial boundaries in 2-D short-axis echocardiograms while at the same time reducing speckle. Speckle is modeled as multiplicative noise, and approximated by additive stationary Gaussian white noise on a logarithmic scale. In our algorithm, shrinkage of wavelet coefficients via soft thresholding within finer scales is carried out on coefficients of logarithmically transformed echocardiograms. Nonlinear feature emphasis combined with hard thresholding within middle levels of transform space are performed subsequently on wavelet coefficients. The first operation reduces speckle while the second step accomplishes structure and object boundary enhancement. Preliminary results suggest that the algorithm can remove speckle noise and enhance contrast along boundaries of importance to cardiologists. We have applied this algorithm to echocardiograms of varying quality, and present both experimental analysis and sample results.
Realistic model calculations based on the Kubo theory for the thermal conductivity of amorphous insulators

Abstract The thermal conductivity of models of amorphous silicon and vitreous silica are discussed. In previous work on amorphous silicon, 216-and 1000-atom models were studied within the Kubo theory and the harmonic approximation using the Stillinger-Weber potential and good agreement with the experimental high-temperature apparent saturation value was obtained. In order to test the model dependence of such results we performed calculations for models based on the Keating potential. The Keating model apparently gives much less force-constant disorder than does the Stillinger-Weber model, as evident from the N dependence and the frequency range of localized states. We also present results of calculations for vitreous silica based on the Feuston-Garofalini model that we relaxed, using their potential, to zero pressure. The results for vitreous silica are in fair agreement with experiment at temperatures above 100K which corresponds to the lowest normal-mode frequency contained within the model.